2011 KRRI Technical Papers Abstracts
2012. 1 CONTENTS
Chapter 1. Bogies and Vehicles ······························· 1
1-01 Measurement of the Disc-Pad Friction Coefficient for Mechanical Brakes Using Direct and Indirect Methods 1-02 Experimental Investigation of Composite Sandwich Square Tubes under Quasi-Static and Dynamic Axial Crushing 1-03 A Study on Crushing Behaviors of Composite Circular Tubes with Different Reinforcing Fibers 1-04 Experimental and Numerical Investigations of Mode I Delamination Behaviors of Woven Fabric Composites with Carbon, Kevlar and Their Hybrid Fibers 1-05 Evaluation of the Material Properties of an OFHC Copper Film at High Strain Rates Using a Micro-Testing Machine 1-06 Effect of Punch Angle on Energy Absorbing Characteristics of Tube-Type Crash Element 1-07 Parametric Study of Lateral Stability for a Railway Vehicle 1-08 Numerical Stress Analysis and Rolling Contact Fatigue of White Etching Layer on Rail Steel 1-09 Longitudinal Strain Monitoring of Rail Using a Distributed Fiber Sensor Based on Brillouin Optical Correlation Domain Analysis 1-10 Simultaneous Two-Axis Vibration Measurement of a Nonmetallic Cylinder by Electromagnetic Induction and Metallic Foil Loops 1-11 3D Finite Element Analysis of Friction Stir Welding of Al6061 Plates 1-12 Failure Mode Analysis and Friction Material Development of the KTX Tread Brake 1-13 Evaluation of Residual Stress for Thermal Damage of Railway Wheel Tread 1-14 Effect of Punch Shapes on Failure Instability of Expansion Tube 1-15 Vibration Analysis of Tread Brake Block in the Brake Dynamometer for the High Speed Train 1-16 Dynamometer Tests of Brake Shoes under Wet Conditions for the High Speed Trains 1-17 Remote Sensing of the Lateral Force for the Scaled Active Steering Railway Vehicle 1-18 Expanded Uncertainty in Measurements of Vertical and Lateral Behaviors for the Rubber-Tired Light Rail Vehicle 1-19 Strength Analysis of Chassis Structure for Medium-Sized Low-Floor Vehicle under Dynamic Load Cases 1-20 A Feasibility Study on the Energy Harvesting Technology for the Real Time Monitoring System of the Railroad Vehicle 1-21 A Study on the Wireless Onboard Monitoring System for Railroad Vehicle Axle Bearings Using the SAW Sensor 1-22 Integrity Evaluation of Railway Bogie Using Infrared Thermography Technique 1-23 Analysis of Fracture Behavior in Polymer Matrix Composites by Infrared Thermography 1-24 End-Shape Effect for Stress Concentration Reduction of Composite Single-Lap Bonded Joint 1-25 Stress Reduction Methods of GFRP/Mg Single Lap Bonded Joints : Finite Element Analysis 1-26 Setting the Service Reliability Target for Meeting the Punctuality Requirement of the Railroad System 1-27 A Study on Evaluating System Performance for Light-Weight Rolling Stock 1-28 Designing a Microphone Array System for Noise Measurements on High-Speed Trains 1-29 Effects of Surface Defects on Rolling Contact Fatigue of Rail 1-30 Hierarchical Views for Distributed Databases of Semantically Condensed Data through Web Links to Sensor Data 1-31 A Web Data Exchange System for Cooperative Work in CAE 1-32 An Abbreviate Representation for Semantically Indexing of Physically Massive Data Out of Sensor Networks on the Rove 1-33 A Study on the Fracture Test in Running System of Railway 1-34 Strain Monitoring of Composite Steel Girder Bridge Using Distributed Optical Fibre Sensor System 1-35 Three-Dimensional Steady-State Rolling Contact Analysis Using Finite Element Method 1-36 Three-Dimensional Transient Rolling Contact Analysis of Similar Elastic Cylinders 1-37 Influence of the Speeds on the Curve Squeal Noise of Railway Vehicles 1-38 Prediction of Surface Crack Growth Considering the Wheel Load Increment Due to Rail Defect 1-39 The Study on the Locomotive Cab Design Considering Driver's Physical Characteristics in Korea 1-40 Weight Reducing of Aluminum Extrusion Profiles of a Railway Carbody Based on Optimization Method 1-41 Review of Non-Destructive Evaluation Technologies for Rail Inspection 1-42 Evaluation of Running Safety for Depressed Center Flat Car of 3-axle Bogie 1-43 Analysis on the Running Stability of Rolling-Stock according to Wheel Profile Wear
Chapter 2. Railroad Infrastructures ····················· 44
2-01 Experimental Evaluations of Track Structure Effects on Dynamic Properties of Railway Bridges 2-02 Experimental and Numerical Analyses of an Opening in a Jointed Rock Mass under Biaxial Compression 2-03 Optimization of Alignment Considering Ride Comfort for Superimposition of Vertical and Horizontal Curves 2-04 Lateral Overturning Failures of Old Concrete Gravity Pier on Sandy Soils 2-05 Effect of Crack Width on Chloride Diffusion Coefficients of Concrete by Steady-State Migration Tests 2-06 Experimental and Numerical Investigation on Dynamic Amplification Factors of an Urban Maglev Guideway 2-07 Tilting Train-Induced Roadbed Response on the Conventional Line 2-08 Traffic Safety & Passenger Comforts of a Suspension Bridge Considering Seismic Loads 2-09 Centrifuge-Shaking Table Test for Seismic Performance Evaluation of Subway Station 2-10 Investigation of the Maintenance Criteria for the Rail Surface Defects in High-Speed Railways 2-11 Determination of Upper Limit of Rail Pad Stiffness for Ballasted and Concrete Track of High-Speed Railway Considering Running Safety 2-12 Evaluation of Train Running Safety During Construction of Temporary Bridge on Existing Railway 2-13 An Experiment and Analysis of Precast Concrete Baseplate on Bimodal Tram Dedicated Bridge 2-14 A Study on the Basic and Compression Characteristics of Lightweight Waste for Use as Fill Materials 2-15 An Experimental Study on Local Stability of Eco-Block 2-16 Development of FBG Accelerometer for Railway Tunnel Vibration 2-17 Evaluation of Dynamic Stability for Structural Bar Reinforced Precast and Prestressed Retaining Wall for Moving Train Load 2-18 Dynamic Response Characteristics for Two-Layered Trackbed Structure by Train Load 2-19 Reduction of Shear Strength of Railway Roadbed Materials with Freezing-Thawing Cycle 2-20 A Comparative of Ground Stress with Difference of The Fixed Point Loading and Moving Wheel Loading 2-21 Evaluation of Correlation between Strain Mudulus (Ev2) and Deformation Modulus (ELFWD) Using Cyclic Plate Loading Test and LFWD
Chapter 3. Electric & Signal System ················· 65
3-01 Conceptual Design for HTS Coil in Superconducting Electromagnet for Maglev 3-02 Characteristics of Persistent-Current Mode of HTS Coil on Superconducting Electromagnet 3-03 Improvement of Thrust Force Properties of Linear Synchronous Motor for an Ultra-High-Speed Tube Train 3-04 Parameter Design of IPMSM With Concentrated Winding Considering Partial Magnetic Saturation 3-05 Thrust Performance Improvement of a Linear Induction Motor 3-06 Magnetic Interference on the Infrastructure for a Super-Speed Tube Train 3-07 License Plate Extraction Method for Identification of Vehicle Violations at a Railway Level Crossing 3-08 Implementation of a Condition Monitoring System for Mold Transformers in DC Substations 3-09 Development of an Arc Detector Assessment System by Loss of Contact Between Pantograph and Contact Wire in Electric Railway 3-10 Analysis of Iron-filings Trapping Characteristics on Concrete Slab Track using Permanent Magnet 3-11 A Study on an Airgap Control System in a Rotary-small-scaled Linear Induction Motor for Railway 3-12 Development of a Series Hybrid Propulsion System for Bimodal Tram 3-13 Harmonic Frequency Analysis of Interlocking System for Rolling Stock Operation in Electrical Railroads 3-14 Analysis of Return Current for Rolling Stock Operation on Electrical Railroads 3-15 Analysis of Interoperability Test between a Different Kind of Train Control System 3-16 Vehicle Running Characteristic Simulator Using Induction Motor 3-17 Evaluations of the Robustness of Guidance Controller for a Bimodal Tram 3-18 The Design and Analysis of Recognition Structure for Absolute Train Positioning System of High-speed Maglev Train System 3-19 A Study on the Reliability/Safety Assessment and Improvement of USN Gateway for Train Control 3-20 Performance Evaluation of Wireless Sensor Networks in the Subway Station of Workroom 3-21 Development of a Simulator for Radio Propagation Path Loss in Tunnel at 18GHz 3-22 Intelligent Video Surveillance System using RFID Technology 3-23 A Study on a Configuration of the Load Characteristic Evaluation Device Using Hydraulic Power for the Analysis of the Tilting Kinetic Mechanism 3-24 Development of the Operation Simulator for the PRT System 3-25 A Study on Establishment of Signaling Systems to Speed up Conventional Railway 3-26 Development of Door Control Unit for the Electric Plug-in Door of Subway Train 3-27 An Analysis on Rise of Rail Potential and A Study on Control Method for It in DC Feeding System 3-28 A Study on the Real Time Measuring Technique of Stray Current by Using Return Current Ratio In the DC Railway System 3-29 A Study on Fault Location Estimation Technique Using the distribution Ratio of Catenary Current in AC Feeding System 3-30 Bidirectional Alarm Equipment for Protection for Trackside Worker using Bone-anchored Speaker
Chapter 4. Environmental Engineering ··············· 95
4-01 Novel Air Filtration Device for Building Air Handling Unit 4-02 Instability Analysis in Curve Noise of Urban Railway Systems for Optimal Steering Bogie Development 4-03 Experimental Study on Particle Collection Efficiency of Axial-Flow Cyclone in Air Handling Unit 4-04 Investigation of Airborne Microorganism in Cabin of the KTX 4-05 Development of Air Cleaning Roll-Filter for Improving IAQ in Subway 4-06 Air Quality in the Subway Cabins of the Seoul Metropolitan Area and Analysis of Its Influencing Factors Using Multivariate Statistics 4-07 A Study for Characteristics of PM10 in the Subway passenger cabins 4-08 A Study on the Combustion Characteristics and Greenhouse Gas Emissions from Rice Husks with Varied Heat Fluxes 4-09 Full-Scale Test of Smoke-Control Performance of a Subway Tunnel 4-10 The Evaluation of GHG Emissions in Railroad Construction Sector 4-11 A Research on the Greenhouse Gas Emission Reduction of Railway Structure Construction Stage 4-12 Analysis of Vortex Shedding Phenomena around Pantograph Panhead for Train Using Large Eddy Simulation 4-13 The Distribution Characteristics of Carbon Dioxide in Indoor School Spaces 4-14 Adsorption and Desorption Characteristics of Carbon Dioxide at Low Concentration on Zeolite 5A and 13X 4-15 Study on the Removal of Carbon Dioxide in the Subway Cabin Using Zeolite Type Carbon Dioxide Adsorbent 4-16 A Study on the Performance Test and Acoustic Design of Interference Type Noise Reduction Device for Railway Noise
Chapter 5. Others ···················································· 111
5-01 A Multi-Class Closed Queueing Maintenance Network Model with a Parts Inventory System 5-02 A Study on Setting Up National Railway Safety Target 5-03 A Study on Revising Train Departure Time for Reducing Electric Power Consumption 5-04 Track Assignment and Load Planning Problems in Railway Container Terminals 5-05 Metaheuristics of the Rail Crane Scheduling Problem 5-06 Analysis of PRT Station Capacity Based on Micro Simulation 5-07 Analysis on Recognition and Current Use of Pallets for Through Transit 5-08 Analysis of Operational Issues for ICT-based On-Board Train Control System 5-09 A Study on the Train Composition Requirements for Safety Operation of Urban-Transit 5-10 A Study on the DB Establishment and Traceable Management of the Urban Transit Standardization Project 1-01 Measurement of the Disc-Pad Friction Coefficient for Mechanical Brakes Using Direct and Indirect Methods
First Author Abstract
Young-Guk Kim It is necessary to guarantee the proper brake force to stop a train safely in a limited distance and o adjust its speed. [email protected] Currently, most trains are run by electrical power and 82-31-460-5612 have a combined electrical and mechanical (friction) braking system. The mechanical brake force is determined by many parameters, such as the friction coefficient of the brake disc and pad, the pressure in the brake cylinder, the Journal Info. brake cylinder’'s cross sectional area and the brake linkage ratio. In general, the friction coefficient data of the brake SCIE disc and pad have been taken through a dynamo-test in a laboratory, but these data might not be well matched with International Journal of Automotive Technology real data under operating conditions because of the difference in data acquisition conditions. The present study Vol. 21 No. 1 examined two methodologies that can measure the friction 2011. 2 coefficient of the brake pad and disc based on a train’'s real operating conditions. The first method was the direct method, which measured the brake force and clamping force applied on the mechanical brake by using strain gauges installed on the brake to calculate the friction coefficient. The second was an indirect method that obtained the friction coefficient by using the weight of the train and the equivalent brake force. Those variables were calculated from the longitudinal dynamic characteristics, such as resistance to motion, gradient resistance and curved resistance. These two methodologies were used to obtain the disc-pad friction coefficient for the mechanical brakes of a Korean high-speed train (HSR350x).
- 1 - 1-02 Experimental Investigation of Composite Sandwich Square Tubes under Quasi-Static and Dynamic Axial Crushing
First Author Abstract
Jung-Seok Kim In this study, the crush behaviors of square sandwich [email protected] composite tubes with woven fabric carbon/epoxy skins and 82-31-460-5663 aluminum honeycomb cores with the different honeycomb cell sizes and tube sizes were evaluated. For the evaluation, four different kinds of tubes were fabricated and crushed under quasi-static and dynamic impact loads. Journal Info. The impact tests were carried out using heavy wagons. From the test results, the crushing mode under the SCIE dynamic load was changed into more stable collapse than Advanced Composite Materials the corresponding static tests. Additionally, the increased Vol. 20 No. 4 bond strength between the honeycomb core and the 2011. 8 composite face leaded to a higher energy absorption capability.
- 2 - 1-03 A Study on Crushing Behaviors of Composite Circular Tubes with Different Reinforcing Fibers
First Author Abstract
Jung-Seok Kim In this study, the failure modes and energy [email protected] absorption capabilities of different kinds of circular tubes made of carbon, Kevlar, and carboneKevlar 82-31-460-5663 hybrid fibers composites with epoxy resin have been evaluated. The relationship between the crushing parameters (specific energy absorption, maximum Journal Info. peak load, mean crushing load) and the material properties for different fibers and patternswas also SCI investigated. The fabric carbon/epoxy tubes had the International Journal of Impact Engineering best energy absorption capability (specific energy absorption of 81.7%). In contrast, the tubes made of Vol. 38 No. 4 Kevlar showed the worst energy absorption 2011. 4 capability. Based on the linear regression analysis results, the crushing parameters generally showed good correlation with the compressive strength and shear modulus. In particular, the specific energy absorption of the tubes with the brittle fracture mode revealed the strongest correlation with the compressive strength (R-square value ¼ 0.90).
- 3 - 1-04 Experimental and Numerical Investigations of Mode I Delamination Behaviors of Woven Fabric Composites with Carbon, Kevlar and Their Hybrid Fibers
Corresponding Author Abstract
Jung-Seok Kim This paper studied the effect of the hybridization of [email protected] carbon and Kevlar fibers on mode I interlaminar 82-31-460-5663 fracture toughness and crack propagation behaviors with double cantilever beam (DCB) tests. The crack propagation characteristics, crack growth trend and rate, and fracture surfaces were observed using an Journal Info. optical microscope and SEM micrographs for the three different types of materials. Moreover, details SCIE of the stress distribution around the crack tip and International Journal of Precision Engineering the crack propagation pattern across the width of the and Manufacturing DCB specimen were investigated using the finite Vol. 12 No. 2 element method, including a cohesive element. The 2011. 4 mode I interlaminar fracture toughness of Carbon-Kevlar hybrid/epoxy was nearly average for carbon/epoxy and Kevlar/epoxy. The maximum load predicted by the numerical method showed good agreement within an error of 5% with the experimental results.
- 4 - 1-05 Evaluation of the Material Properties of an OFHC Copper Film at High Strain Rates Using a Micro- Testing Machine
First Author Abstract
Jin-Sung Kim The material properties of an oxygen-free high thermal conductivity (OFHC) film with a thickness [email protected] of 0.1 mm were evaluated at strain rates ranging 82-31-460-5266 from 10−-3/s to 103/s using a high-speed material micro-testing machine (HSMMTM). The high strain-rate material properties of thin films are important especially for an evaluation of the Journal Info. structural reliability of micro-formed parts and MEMS products. The high strain-rate material testing methods SCI of thin films, however, have yet to be established to the point that the testing methods of larger Experimental Mechanics specimens for electronics, auto-body, train, ship, and Vol. 51 No. 6 ocean structures are. For evaluation, a new type of HSMMTM was developed to conduct high-speed tensile 2011. 6 tests of thin films. This machine is capable of testing at a sufficiently high tensile speed with an electromagnetic actuator, a novel gripping mechanism, and an accurate load measurement system. The OFHC copper film shows high strain-rate sensitivity in terms of the flow stress, fracture elongation, and strain hardening. These measures increase as the tensile strain rate increases. The rate-dependent material properties of an OFHC copper film are also compared with those of a bulk OFHC copper sheet with a thickness of 1 mm. The flow stress of an OFHC copper film is relatively low compared to that of a bulk OFHC copper sheet in the entire range of strain rates,
- 5 - 1-06 Effect of Punch Angle on Energy Absorbing Characteristics of Tube-Type Crash Element
Corresponding Author Abstract
Tae-Soo Kwon As a crash energy absorber, a tube-type crash element(expansion tube) dissipates kinetic energy [email protected] through the internal deformation energy of the tube 82-31-460-5263 and frictional energy. In this paper, the effects of the variation of punch angles on the energy absorbing characteristics of expansion tubes were studied by quasi-static tests with three punch angles Journal Info. (15°, 30°, 45°). A finite element analysis of the tube expanding process applying a shear friction model SCIE (m=τmax/K) was carried out to confirm the variation of the shear friction factor with respect to punch International Journal of Automotive Technology angles using the inverse method. In addition, additional analysis were performed with angles of Vol. 12 No. 3 20°, 25°, 35°, and 40° to study the effect of the 2011. 6 punch angles on the internal deformation energy, frictional energy, and expansion ratio of the tubes. The results of the experiment and finite element analysis showed that the shear friction factor was inversely proportional to the punch angles and a specific punch angle existed at which the absorbed energy and expansion ratio did not increase any further.
- 6 - 1-07 Parametric Study of Lateral Stability for a Railway Vehicle
First Author Abstract
Joon-Hyuk Park This paper deals with the lateral stability for a [email protected] railway vehicle. Particularly, nonlinear critical speed is investigated via bifurcation analysis. Shooting 82-31-460-5276 method and trust region algorithm are applied to calculate the limit cycle of the nonlinear dynamic vehicle model. In case of the investigated vehicle Journal Info. model, the influences of the suspension parameters on the critical speeds are not large. The effects of SCIE friction coefficient are also small. However, there is Journal of Mechanical an overall consistency that the nonlinear critical Science and Technology speed is decreased when the stiffness of the suspension Vol. 25 No. 7 is reduced. Study of the excitation conditions where 2011. 7 the stable limit cycles occur gives very useful information to understand the nonlinear dynamic behavior of a railway vehicle and to test the vehicle with roller rig test stands. According to the results, the direction of the excitation is very important as well as the amplitude and frequency to acquire accurate nonlinear critical speed.
- 7 - 1-08 Numerical Stress Analysis and Rolling Contact Fatigue of White Etching Layer on Rail Steel
First Author Abstract
Jung-Won Seo White Etching Layer is a phenomenon that occurs [email protected] on the surface of rails due to wheel/rail interactions such as excessive braking and acceleration. We have 82-31-460-5210 investigated rolling contact fatigue damage and the behavior of WEL using the twin disc test and Finite Element analysis. WEL was simulated by wheel flat Journal Info. tests. Two types of cracks were observed to occur within WEL specimens after the rolling contact test. SCI The shortest fatigue life from Finite Element and International Journal fatigue analysis was evaluated using the starting of Fatigue point of WEL, and the results were consistent with Vol. 33 No. 2 those from contact fatigue tests. 2011. 2
- 8 - 1-09 Longitudinal Strain Monitoring of Rail Using a Distributed Fiber Sensor Based on Brillouin Optical Correlation Domain Analysis
First Author Abstract
Hyuk-Jin Yoon A fiber-optic distributed sensor system is configured to measure the longitudinal strain distribution of a [email protected] rail in real time. The system is based on the 82-31-460-5565 Brillouin correlation domain analysis (BOCDA), in which the variation of local Brillouin frequency (νB) is measured that linearly depends on the strain applied to the optical fiber. In the test measurement, Journal Info. the longitudinal strain distribution along a 2.8 m rail SCI is measured under different loading conditions with a spatial resolution of 3.8 cm and an accuracy of ±15 NDT&E με. International
Vol. 33 No. 2 2011. 2
- 9 - 1-10 Simultaneous Two-Axis Vibration Measurement of a Nonmetallic Cylinder by Electromagnetic Induction and Metallic Foil Loops
First Author Abstract
Soon-Woo Han This work presents a method based on electromagnetic induction for the simultaneous non-contact measurement of [email protected] two-axis lateral vibrations of a nonmetallic cylinder. 82-31-460-5537 The suggested method employs two pairs of hollow metallic loops, four pairs of permanent magnets and two solenoids. When the cylinder vibrates, eddy currents are generated in the metallic loops due to Journal Info. electromagnetic induction. The current in one pair of loop is induced by the lateral vibration in one SCIE direction, while the other by the lateral vibration in the perpendicular direction. The induced currents can Journal of Mechanical be sensed through the remotely installed solenoids. Science and Technology While the proposed technique can be useful for the Vol. 25 No. 8 vibration measurement in hot or insulated cylinders, 2011. 8 for which a contact type sensor is hardly applicable, the present study is focused on its underlying measurement mechanism and fundamental experiments. To this end, two-axis vibrations and frequency response functions of a thin nonmetallic cylinder were measured simultaneously by the proposed sensor. They were compared with those extracted by using commercial accelerometers to check the working performance of the proposed measurement technique. The effects of some parameters in the proposed technique, such as the length of the loop, were also investigated.
- 10 - 1-11 3D Finite Element Analysis of Friction Stir Welding of Al6061 Plates
First Author Abstract
Byeong-Choon Goo Friction stir welding (FSW) is a solid state joining [email protected] method patented in 1991 by The Welding Institute (TWI). It is widely used for joining light metals 82-31-460-5243 such as Al and Mg alloys. Foreign railway vehicle manufacturing companies have been applying FSW to car body welding, but domestic companies are in the Journal Info. beginning of feasibility study. Therefore, lots of experimental and analytical study is needed. In this Journal of KWJS study, three-dimensional finite element modeling of Vol. 29 No. 4 the friction stir welding of two Al6061-T6 plates 2011. 8 was carried out. And temperature field and residual stresses were obtained and compared to experimental results in the literature. It is found the analytic thermal field is in a good agreement with the experimental results, but there are some differences between numerical and experimental residual stresses.
- 11 - 1-12 Failure Mode Analysis and Friction Material Development of the KTX Tread Brake
Corresponding Author Abstract
Byeong-Choon Goo The shoe brake of the KTX is used in low speed [email protected] when the electric brake is not effective. The main purpose of the shoe brake is to stop the train to a 82-31-460-5243 desired stop point at the station. Lots of defects have been encountered in the shoe brake unit since the KTX started its operation. To improve the Journal Info. reliability of shoe brake unit of the KTX power car, first of all, failure modes of the KTX shoe brake Journal of the Korean Society for Railway unit were analyzed. Main failure modes are cracks in Vol. 14 No. 2 the shoe friction material and fracture in the welded joints of the shoe backing steel structure. Several 2011. 4 methods to remove the defects of the shoe brake unit were proposed and on-board tests were carried out: Increase of the strength of the shoe key and shoe cam, which decreased a little the occurrence of cracks in the shoe friction material; Redesign of the shoe backing steel structure, which eliminated the occurrence of the cracks in the backing plate but could not solve completely the crack problem in the shoe friction material; Development of a new friction material, which with redesign of the shoe backing steel structure could solve satisfactorily the crack problem in the shoe friction material.
- 12 - 1-13 Evaluation of Residual Stress for Thermal Damage of Railway Wheel Tread
First Author Abstract
Seok-Jin Kwon The thermo-mechanical interaction between brake [email protected] block and wheel tread during braking has been found to cause thermal crack on the wheel tread. 82-31-460-5249 Due to thermal expansion of the rim material, the thermal cracks will protrude from the wheel tread and be more exposed to wear during the wheel/block Journal Info. contact than the rest of the tread surface. The wheel rim is in residual compression stress when is new. Journal of the Korean Society for Precision After service running, the region in the tread has Engineering reversed to tension. This condition can lead to the
Vol. 28 No. 5 formation and growth of thermal cracks in the rim 2011. 5 which can ultimately lead to premature failure of wheel. In the present paper, the thermal cracks of railway wheel, one of severe damages on the wheel tread, were evaluated to understand the safety of railway wheel in running condition. The residual stresses for damaged wheel which are applied to tread brake are investigated. Mainly X-ray diffusion method is used. Under the condition of concurrent loading of continuous rolling contact with rails and cyclic frictional heat from brake blocks, the reduction of residual stress is found to correlate well with the thermal crack initiation.
- 13 - 1-14 Effect of Punch Shapes on Failure Instability of Expansion Tube
Corresponding Author Abstract
Tae-Su Kwon The rupture of an expansion tube is mainly affected [email protected] by the expansion ratio and the external shape of the punch used to expand the tube. In order to prevent 82-31-460-5263 the tube from rupture, the effect of the external shape of the punch should be considered in the design. The aim of this paper is to confirm the Journal Info. effect of key design parameters of the punch on rupture of the tube using a finite element analysis Transactions of KSAE with a ductile damage model. The results of the Vol. 19 No. 2 analysis indicated that the expansion ratio of the 2011. 2 tube was mainly affected by variation of the radius of the punch. However, the rupture was more affected by variation of the punch angle than the radius of the punch. The existence of a specific punch angle at which rupture did not occur, even if the radius of the punch was increased, was found from the results.
- 14 - 1-15 Vibration Analysis of Tread Brake Block in the Brake Dynamometer for the High Speed Train
First Author Abstract
Min-Soo Kim This paper deals with the frequency analysis of the [email protected] abnormal vibration in the specific speed range when the tread brake test is applied in the brake 82-31-460-5205 dynamometer. Generally brake system of railway vehicles has a crucial role for the safety as well as riding quality of passengers. And dynamometer tests Journal Info. are widely used to evaluate the friction and wear performance of railroad friction composition brake International Journal of Systems Applications shoes including the emergence brake, continuous brake, Engineering & Development and so on. Experiments on the brake dynamometer
Vol. 5 No. 1 for the high speed train are provided to illustrate the 2011. 2 frequency analysis of the abnormal vibration in vehicle speed at 140 [km/h] and 70 [km/h] under the 920 [mm] wheel diameter using the 3-axis accelerometers.
- 15 - 1-16 Dynamometer Tests of Brake Shoes under Wet Conditions for the High Speed Trains
First Author Abstract
Min-Soo Kim This paper discuss comparative studies of the wheel [email protected] tread brake with composite brake blocks between 82-31-460-5205 under conditions with dry and wet using the dynamometer tests for the high speed trains. Generally brake system of railway vehicles has a crucial role for the safety as well as riding quality of Journal Info. passengers. And brake dynamometers are widely used
International Journal of to evaluate the performance of brake systems and Systems Applications test the brake parts under various environments Engineering & Development (weight, velocity, brake force, wet-dry conditions). Vol. 5 No. 2 Especially, in the process of the brake stops, the 2011. 4 friction coefficients between under dry and wet conditions must not deviate from each other by more than 15% under the same testing conditions. Experiments on the brake dynamometer for the high speed trains are shown to illustrate the comparative studies of the tread brake of dynamometer tests between under dry and wet conditions with initial vehicle speed at 200 [km/h] and 80 [km/h] considering the 920 [mm] wheel diameter, espectively.
- 16 - 1-17 Remote Sensing of the Lateral Force for the Scaled Active Steering Railway Vehicle
First Author Abstract
Min-Soo Kim This paper describes the performance measurement [email protected] system of the active steering railway vehicle with 82-31-460-5205 the scaled test bed using the acquisition telemetry system about the wheel lateral force. Active steering system of railway vehicles has proven its ability to bridge the gap between stability and curve Journal Info. friendliness. This scaled test-bed system consists of two steering actuators, a steering controller, and International Journal of Systems Applications various sensor systems to detect lateral displacement, Engineering & Development vibration, track curvature, and sensor systems. To compare with the various control strategies, we Vol. 5 No. 1 installed the telemetry systems on the steering 2011. 2 wheelsets to detect the wheel/rail lateral force. Running test results of 1/5 scaled active steering vehicle on the curved track show that the proposed measuring system has good performance.
- 17 - 1-18 Expanded Uncertainty in Measurements of Vertical and Lateral Behaviors for the Rubber-Tired Light Rail Vehicle
First Author Abstract
Yeon-Su Kim In the public transport vehicle, vertical and lateral [email protected] behaviors have a significant effect on ride comfort 82-31-460-5730 and safety of passengers on curved track. Based on vertical and lateral vibration accelerations measured on floor level in passenger compartment when the K-AGT ran on the minimum curvature of the Journal Info. 2.4km-test track in driverless mode, expanded uncertainties in measurement were estimated Key Engineering Materials statistically. In addition, vertical and lateral dynamic behaviors of the K-AGT were discussed in this Vols. 452-453 paper. 2011. 1
- 18 - 1-19 Strength Analysis of Chassis Structure for Medium-Sized Low-Floor Vehicle under Dynamic Load Cases
First Author Abstract
Yeon-Su Kim For the medium-sized low-floor bus, backbone [email protected] structure of chassis was designed to have light-weight 82-31-460-5730 structure with SAPH (Steel Automobile Press Hot rolled) 440. Strength for the designed backbone structure was also analyzed by finite element method under various dynamic load cases considered in this Journal Info. paper. On the basis of the analysis results, the structural safety for the designed backbone structure Key Engineering Materials was evaluated and discussed in this paper.
Vols. 452-453 2011. 1
- 19 - 1-20 A Feasibility Study on the Energy Harvesting Technology for the Real Time Monitoring System of the Railroad Vehicle
onitoring System of the Railroad Vehicle Load CasesRail Vehicle First Author Abstract
Jae-Hoon Kim This study was intended to identify the applicability [email protected] of energy harvesting technologies which is regarded 82-31-460-5248 the new and renewable energy for real time/wireless monitoring the intelligent railroad system. The surrounding energy generated under the normal operation environment was monitored using high Journal Info. speed railroad vehicle in operation in an attempt to evaluate the power of energy harvesting and the Transactions of the Korea Society of applicability of energy harvesting monitoring technologies Mechanical under the circumstance in which the thermal energy Engineers B and vibration energy are generated.
Vol. 35 No. 9 2011. 9
- 20 - 1-21 A Study on the Wireless Onboard Monitoring System for Railroad Vehicle Axle Bearings Using the SAW Sensor
Monitoring System of the Railroad Vehicle Load CasesRail Vehicle First Author Abstract
Jae-Hoon Kim This study aimed to replace the current discontinuous [email protected] rail monitoring system by applying “Plug and Play” 82-31-460-5248 technology to rail system monitoring to enable real-time monitoring, and by confirming on-condition maintenance efficiency and reliability. It examined a wireless sensor monitoring system which uses SAW Journal Info. (Surface Acoustic Wave) technology to monitor temperature changes in the axle box bearing of Lecture Notes of the railroad vehicles during operation. The results of the Institute for Computer experiment were compared with HDB measurements Sciences, Social Informatics and to confirm the reliability of the real-time monitoring Telecommunications results measured on vehicles during operation. Engineering: Sensor Systems and Software
Vol. 57 No. 2 2011. 10
- 21 - 1-22 Integrity Evaluation of Railway Bogie Using Infrared Thermography Technique
First Author Abstract
Jeong-Guk Kim The lock-in thermography was employed to evaluate the [email protected] integrity of railway bogies. Prior to the actual application 82-31-460-5518 on railway bogies, in order to assess the detectability of ko주 flaws, the calibration reference panel was prepared with various dimensions of artificial flaws. The panel was composed of structural steel, which was the same material Journal Info. with actual bogies. Through lock-in thermography evaluation the optimal frequency of heat source was Journal of the Korean Society for Nondestructive determined for the best flaw detection. Based on the Testing defects information, the actual defect assessments on railway bogie were conducted with different types of Vol. 31 No. 2 railway bogies, which were used for the current operation. 2011. 4 In summary, the defect assessment results with thermography method showed a good agreement as compared with the conventional inspection techniques. Moreover, it was found that the novel infrared thermography technique could be an effective way for the inspection and the detection of surface defects on bogies since the infrared thermography method provided rapid and non-contact mode for the investigation of railway bogies
- 22 - 1-23 Analysis of Fracture Behavior in Polymer Matrix Composites by Infrared Thermography
First Author Abstract
Jeong-Guk Kim The tensile fracture behavior of polymer matrix [email protected] composite materials was investigated with the aid of 82-31-460-5518 a nondestructive evaluation (NDE) technique. The materials, E-glass fiber reinforced epoxy matrix composites, which are applicable to bogie materials in railway vehicles to reduce weight, were used for Journal Info. this investigation. In order to explain stress-strain behavior of polymer matrix composite sample, the Key Engineering infrared thermography technique was employed. A Materials high-speed infrared (IR) camera was used for in-situ Vols. 452-453 monitoring of progressive damages of polymer matrix 2011. 1 composite samples during tensile testing. In this investigation, the IR thermography technique was used to facilitate a better understanding of damage evolution, fracture mechanism, and failure mode of polymer matrix composite materials during monotonic loadings.
- 23 - 1-24 End-Shape Effect for Stress Concentration Reduction of Composite Single-Lap Bonded Joint
First Author Abstract
Jung-Seok Kim We evaluated the stress-reduction effect for different [email protected] shapes of a composite adherend with or without a 82-31-460-5663 spew fillet. Six different single-lap joint specimens were modeled and assessed using nonlinear finite element analysis. Moreover, we investigated the effect of the stiffness ratio of the adherend and adhesive. The Journal Info. single-lap joint with normal tapering had the highest
Transactions of the stress values, and the single-lap joint with reverse Korea Society of tapering and a spew fillet had the lowest stress Mechanical values. The composite adherends with higher stiffness Engineers A had lower stress values, and the adhesives with Vol. 35 No. 3 lower stiffness had lower stress values. 2011. 3
- 24 - 1-25 Stress Reduction Methods of GFRP/Mg Single Lap Bonded Joints : Finite Element Analysis
First Author Abstract
Jung-Seok Kim In this study, the stress reduction effect was [email protected] evaluated for GFRP/Mg single lap bonded joints 82-31-460-5663 according to six different adherend shapes. Six different types of the single lap joint specimen were modeled and assessed using geometrically nonlinear finite element analysis. Moreover, three dimensional Journal Info. effect of stress distribution for the different adherend shapes was investigated. From the analysis, the Journal of the Korean Society for Railway dissimilar single lap bonded joint with the normal Vol. 14 No. 2 tapering and without the spew fillet (model 2) 2011. 4 showed the highest stress values. In contrast, the peel stress values of both the square ended adherends with the spew fillet (model 3) and the reverse tapered adherends with the spew fillet (model 5) were 65.8% and 65.5% lower than the reference model.
- 25 - 1-26 Setting the Service Reliability Target for Meeting the Punctuality Requirement of the Railroad System
First Author Abstract
Jong-Woon Kim This article deals with a problem of setting [email protected] reliability targets of the railroad systems where the 82-31-460-5222 punctuality target is given to the operator and a penalty is imposed for the year when the target is not met. The operator should set the reliability targets of the railroad system and sub-systems Journal Info. because the reliability affects the expected number of years when the penalty is imposed. This paper Journal of the Korean Society for Railway presents a procedure for setting the service reliability Vol. 14 No. 1 target and equations to calculate the expected number of years when the penalty is imposed and the 2011. 2 probability that the operator should pay the penalty per year according to the mean kilometer between service failures of the railroad system and sub-systems.
- 26 - 1-27 A Study on Evaluating System Performance for Light-Weight Rolling Stock
Corresponding Author Abstract
Jong-Woon Kim In this paper, a method is proposed to evaluate a [email protected] number of alternatives for light-weight rolling 82-31-460-5222 stock recommended from experts in rolling stock and to decide an optimal alternative. At first, many customer needs from various fields in railroad are drawn and weights of customer needs Journal Info. are decided by AHP. Secondly, technical Journal of the Korean requirements that should be real specifications for Society for Railway light-weight rolling stock are set and weights of Vol. 14 No. 6 technical requirements are decided by QFD. 2011. 12 Finally, we evaluate some proposed alternatives and conclude an optimal alternative of light-weight rolling stock with TOPSIS.
- 27 - 1-28 Designing a Microphone Array System for Noise Measurements on High-Speed Trains
First Author Abstract
Hee-Min Noh In this paper, noise source localization of the Korean [email protected] high speed train was conducted by using delay and 82-31-460-5564 sum beamforming method of a microphone array. At first, the microphone array having irregular configuration was designed and the resolution of which was analyzed from parameters such as 3-dB Journal Info. bandwidth and maximum side-lobe level. After the demonstration, the microphone array was applied on Journal of the Korean Society for Railway the high speed train and noise localization of the
Vol. 14 No. 6 high speed train driving at 300 km/h was performed successfully. 2011. 12
- 28 - 1-29 Effects of Surface Defects on Rolling Contact Fatigue of Rail
First Author Abstract
Jung-Won Seo Rolling contact fatigue damages on the surface of [email protected] rail such as head check, squats are one of growing 82-31-460-5210 problems. Squats are originated from the white etching layer (WEL) or the dent on rail surface and accompanied with dark spots including cracks. Another form of rail surface damage, known as Journal Info. "Ballast imprint" has become apparent. This form of
Procedia damage is associated with ballast particles becoming Engineering trapped between the wheel and the surface of rail.
Vol. 10 In this study, we have investigated whether the 2011. 6 ballast imprint is an initiator of head check type cracks using the twin disc test and Finite element analysis. The tests were conducted using specimens with artificial defects. FE analysis were used to investigate stresses and strains in subsurface of defects. The test results show that cracks initiate and propagate in dents larger than a certain size.
- 29 - 1-30 Hierarchical Views for Distributed Databases of Semantically Condensed Data through Web Links to Sensor Data
First Author Abstract
Min-Hwan Ok A number of sensor networks may produce a huge [email protected] amount of data, and there has been a necessity the 82-31-460-5287 data are processed in a single system. However the viewing or navigating toward data interested has not been evolved suitably because of the overwhelming volumes of sensor data. This work introduces a data Journal Info. browsing technique from distributed databases of sensor data condensed according to semantics shared Communications in among servers. Web links of a colored presentation Computer and Information Science could enhance the view of sensor data indexed along Vol. 206 a hierarchy from distributed databases in the 2011. 9 geographic regions.
- 30 - 1-31 A Web Data Exchange System for Cooperative Work in CAE
First Author Abstract
Min-Hwan Ok The popular Social Network Service, SNS, induces [email protected] an open system for collaboration. A data exchange 82-31-460-5287 system is opened without any grant as a Computer- supported Cooperative-work tool for Computer-Aided Engineering via Web interface. The SNS plays the role for security instead. SNS is advantageous in Journal Info. recruiting members adequate to the cooperative work, and this open system could be a good workplace Communications in under the paradigm of convergence. Computer and Information Science Vol. 167 2011. 6
- 31 - 1-32 An Abbreviate Representation for Semantically Indexing of Physically Massive Data Out of Sensor Networks on the Rove
First Author Abstract
Min-Hwan Ok Vehicles are becoming smart by their equipments [email protected] with sensors and actuators. The equipment would 82-31-460-5287 report the detected malfunction status or monitored faulty part to the driver, and it should report that to a sort of a traffic control center as the defective car might require a professional support. It is preferable Journal Info. to transmit the collected data after reducing the amount data. In this work, an abbreviation method is Lecture Notes in proposed to preserve the substitutes of data probably Computer Science significant. The abbreviation reduces the amount of Vol. 6724 data to be transmitted and stored, by abbreviating 2011. 5 the data into substitutes remained useful to the calculations in detecting malfunction status or monitoring faulty part.
- 32 - 1-33 A Study on the Fracture Test in Running System of Railway
First Author Abstract
Sung-Cheol Yoon This paper describes the results of structural analysis [email protected] and loading test of a bogie frame. The purpose of 82-31-460-5512 the analysis and test is to evaluate the safety and functionality of the bogie frame under maximum load. The bogie system consist of the bogie frame, suspensions, wheel-sets, a brake system and a Journal Info. transmission system. Of these components, the bogie frame is the major component subjected to the Key Engineering vehicle and passenger loads. The evaluation method Materials used the JIS E 4207 specifications throughout the Vols. 452-453 FEM analysis and static load test. The test results 2011. 1 have shown the bogie frame to be safe and stable under design load conditions.
- 33 - 1-34 Strain Monitoring of Composite Steel Girder Bridge Using Distributed Optical Fibre Sensor System
First Author Abstract
Hyuk-Jin Yoon An I type steel girder was assembled with a [email protected] concrete upper plate and then placed on two roller supports. Four vertical load actuators 82-31-460-5565 were laid on the upper plate to add the vertical load. A single mode optical fiber was attached on the surface of the lower flange of a composite steel girder bridge with a Journal Info. length of 39 m. Longitudinal strain distribution of a composite steel girder bridge is Procedia Engineering monitored directly using optical fibre sensor Vol. 10 system based on Brillouin frequency shift dependency of the strain applied on the 2011. 1 optical fiber. Brillouin scattering signal is generated through the Brillouin optical correlation domain analysis at a selected location. Strain data were acquired at 195 points with the interval of 20 cm over the full range. From the strain data over the entire length of the composite steel girder bridge, the strain distribution shape was shown when the vertical load was added on the bridge.
- 34 - 1-35 Three-Dimensional Steady-State Rolling Contact Analysis Using Finite Element Method
First Author Abstract
Dong-Hyong Lee Because most fatigue cracks in wheel and rail take [email protected] place by rolling contact of wheel and rail in railroad 82-31-460-5246 industry it is critical to understand the rolling contact phenomena, expecially or the three-dimensional situation. This paper presents an approach to steady-state rolling contact problem of three-dimensional contact JournalJournal of the Info.Korean bodies with or without tangential force, based on the finite element method. The steady-state conditions are Society for Precision controlled by the applied relative slip and tangential Engineering force. The three-dimensional distribution of tangential Vol. 28 No. 5 traction and contact stresses on the contact surface 2011. 5 are investigated. Results show that the distribution of tangential traction and contact stresses on the contact surface varies rapidly as a result of the variation of stick slip region. The tangential traction is very close in form to carter's distribution
- 35 - 1-36 Three-Dimensional Transient Rolling Contact Analysis of Similar Elastic Cylinders
First Author Abstract
Dong-Hyong Lee Because most fatigue cracks in wheel and rail take [email protected] place by rolling contact between wheel and rail in 82-31-460-5246 railway industry it is critical to understand the rolling contact phenomena, especially for the three-dimensional situation. In this paper the steady-state and transient rolling contact problem of Journal Info. three-dimensional elastic bodies has been studied. The transient conditions were controlled by the Procedia Engineering applied relative slip. Th variation of tangential Vol. 10 traction and stick-slip region on rolling contact 2011. 6 surface were obtained using the finite element method. The three-dimensional distribution of tangential traction and contact stresses on the contact surface are investigated. Results show that the distribution of tangential traction and contact stresses on the contact surface varies rapidly as a result of the variation of stick-slip region. The tangential traction is very close in form to Carter's distribution that contact region divided into stick and slip region. The contact stress at the leading edge is greater than at the trailing edge and the transient distance increases with small slip.
- 36 - 1-37 Influence of the Speeds on the Curve Squeal Noise of Railway Vehicles
First Author Abstract
Chan-Woo Lee Curve squealing of inter-city railway vehicle is a [email protected] noise with high acoustic pressure and rather narrow 82-31-460-5204 frequency spectra. This noise turns out to be very annoying for the people living in the neighborhood of locations and the passenger in railway vehicle where this phenomenon occurs. Squealing is caused Journal Info. by a self-exited stick-slip oscillation in the wheel-rail contact. Curve squeal noise of railway vehicles that Journal of the Korean passed by a factor of the speed limit, so to Society for Precision overcome in order to improve running performance Engineering is one of the largest technology. In the present Vol. 28 No. 5 2011. 5 paper, characteristic of squeal noise behavior at the Hanvit-200 tilting train test-site. Curve squealing of railway wheels/rail contact occurs in R400-R800 curves with a frequency range of about 4-11kHz. If the curve is less than the radius of wheel/rail contact 엳 새 left-right noise level difference(dBA) shows a significant effect of squeal noise were more likely.
- 37 - 1-38 Prediction of Surface Crack Growth Considering the Wheel Load Increment Due to Rail Defect
First Author Abstract
Hyun-Kyu Jun Prediction of a minimum crack size for growth, [email protected] which is defined as a crack size that grows fast 82-31-460-5228 enough to keep ahead of its removal by contact wear and periodic grinding, is the most demanding work to prevent rail from fatigue failure and develop cost effective railway maintenance strategy. In this Journal Info. study, we investigated the wheel load increment due to a rail defect during a train ran over it, and its Journal of the Korean effect on the minimum crack size for growth. For Society for Precision this purpose, we developed simulation software based Engineering on the Fletcher and Kapoor’'s “"2.5D”" model and Vol. 28 No. 5 measured wheel load increment during a train passed 2011. 5 over a defect. A maximum contact pressure and contact patch size were calculated by 3D FEM and crack growth analyses were performed by varying two of dominant contact contributors; surface friction coefficient(0.1, 0.2, 0.3 and 0.4) and crack aspect ratio. The minimum crack sizes for growth were calculated from 0.29 to 1.44mm depending on the contact conditions. They were decreasing with increasing surface friction coefficient and decreasing with crack aspect ratio(a/b).
- 38 - 1-39 The Study on the Locomotive Cab Design Considering Driver's Physical Characteristics in Korea
First Author Abstract
Don-Bum Choi The ergonomic design approaches are not sufficient [email protected] on the railway system especialy on the locomotives 82-31-460-5563 cab in Korea. Moreover, the specifications on the design are not provided as a legal condition. In this study, the domestic driver's anthropometire characterics were compared against the UIC's design Journal Info. criteria used in the cab design. The problems come from drivers physical characteristics are verified with Journal of the Korean the rolling stock running in Korea meeting the Institute of visitility and operability of the UIC's. These studies PlantEngineering including environmental factors (air conditioning, Vol. 16 No. 3 2011. 9 noise, vibration, control desk layout, seats etc.) are useful on estabilishing the design specification of the driver's cab.
- 39 - 1-40 9 Weight Reducing of Aluminum Extrusion Profiles of a Railway Carbody Based on Optimization Method
First Author Abstract
Soon-Woo Han Optimization of aluminum extrusion profiles of a [email protected] urban railway carbody, especially Korean EMU, 82-31-460-5537 for weight reducing is discussed in this work. A base plate of underframe and side panel of side frame composed of double skin structures, which are heaviest parts of urban aluminum railway Journal Info. carbody are considered for optimization. Topology optimization process is applied to get a optimized
Transactions of the rib structure of base plate. The thickness of ribs Korea Society of and plates of the topologically optimized base plate Mechanical Engineers and the existing side panel are also optimized Vol. 35 No. 2 through size optimization process. The results are 2011. 2 verified by comparing maximum vonMises stresses and maximum deformation of the existing design and the optimized design. It is shown that the weight of a base plate and side panel can be reduced by 12% and the weight of whole carbody by 8.5%.
- 40 - 1-41 9 Review of Non-Destructive Evaluation Technologies for Rail Inspection
First Author Abstract
Soon-Woo Han For railway safety, it is very important to detect [email protected] damages of rails at their early stage because any 82-31-460-5537 undetected damage in a rail can break the rail and cause a serious railway accident. In this paper, several NDT applicable to rail inspections are described. Major damage types in rails are discussed Journal Info. first and the rail inspection technology using conventional piezoelectric ultrasonic transducers, Journal of the Korean which is widely adopted for damage detection of Society for Railway rails, is explained. Other NDT being researched or Vol. 31 No. 4 tested for rail inspection are also discussed as 2011. 8 complementary technologies to the concurrent contact type ultrasonic inspection. Characteristics of each rail inspection technologies are evaluated in order to provide requirements for future development of a new rail inspection method.
- 41 - 1-42 9 Evaluation of Running Safety for Depressed Center Flat Car of 3-axle Bogie
First Author Abstract
Young-Sam Ham For the safety of railway it should be evaluated for [email protected] the running safety by measuring the derailment 82-31-460-5202 coefficient. Although railway has run the fixed and maintained rail, some of railway is derailed. This report shows the results that performed the static load test, main line running test on the basis of the Journal Info. derailment theory and experience. It is executed main line test into more than 90km/h for estimating the Journal of the Korean curving performance and running safety of depressed Society for Precision center flat car of 3-axle bogie. As the test results Engineering could confirm the curving performance and running Vol. 28 No. 5 safety of depressed center flat car of 3-axle bogie 2011. 5 from the results of the wheel unloading, lateral force, derailment coefficient etc. Derailment coefficient was less than 0.6 and lateral force allowance limit and wheel load reduction ratio were enough safe.
- 42 - 1-43 9 Analysis on the Running Stability of Rolling-Stock according to Wheel Profile Wear
First Author Abstract
Hyun-Moo Hur To analyze the effect of wear of wheel profile on [email protected] the running stability of rolling-stock, theoretical 82-31-460-5245 and experimental studies were conducted on the profiles used in conventional lines. In experiment using 1/5 scale model to verity the results of the theoretical analysis, the test results of the critical Journal Info. speed for worn wheel profile samples show similar trend. In case of the conical type wheel
Journal of the Korean profile(prifile 40), the equivalent conicity is Society for Precision increased with flange wear. But in case of the arc Engineering type wheel profile(prifile 20h), the equivalent Vol. 28 No. 5 conicity is decreased with flange wear. And the 2011. 5 critical speed of the bogie was inverse proportion to the equivalent conicity. It is shown that the variation of the crical speed with the wheel wear could be changed according to the design concept and wear pattern of wheel prifile. results of the theoretical and experimental studies are discussed here
- 43 - 2-01 Experimental Evaluations of Track Structure Effects on Dynamic Properties of Railway Bridges
First Author Abstract
Sung-Il Kim The dynamic stability under the passage of a moving [email protected] train has become one of the most important issues in railway bridge designs. A precise application of 82-31-460-5354 the dynamic properties of a structure will lead to a precise description of the dynamic behavior of a structure under moving train loads. A railway bridge Journal Info. is completed with a track structure, which is composed of rail, sleeper and track (concrete or SCIE ballast). A track structure can change the modal Journal of Vibration & properties of the railway bridge, through the Control contribution of stiffness as well as mass effects. Consequently, the critical speed of the train that Vol. 17 No. 12 gives rise to the resonance behavior should be also 2011. 10 changed, with or without the track. In the present study, a twin I-shaped steel composite girder bridge was fabricated as a test specimen, and modal testing was carried out with the installation of non-ballast, ballast track and concrete track. Modal tests were performed with hydraulic dynamic actuators. The natural frequencies, damping ratios and dynamic responses of each type of track structure were observed, along with the variation of magnitudes, frequencies and amplitudes of dynamic loading. From the results, the effects of a track structure on the railway bridge can be evaluated.
- 44 - 2-02 Experimental and Numerical Analyses of an Opening in a Jointed Rock Mass under Biaxial Compression
First Author Abstract
Myung Sagong Tunnel construction in a rock mass produces damage [email protected] around the tunnel by concentration of in situ stress and by construction activity such as blasting. The 82-31-460-5363 generated damage changes the mechanical and hydraulic properties of the rock mass. In this study, the rock fracture and joint sliding behaviors of jointed rock masses with an opening under biaxial Journal Info. compression are investigated through experimental and numerical analyses. The tested rock models have SCI a persistent joint set with dip angles of 30°, 45°, Journal of Sound and and 60° to the horizontal. Under the applied biaxial Vibration compression, tensile crack initiation and propagation are the dominant fracture behaviors around the hole Vol. 48 in a low joint dip angle rock model (i.e. 30° to the 2011. 10 horizontal). The propagation direction of the tensile cracks is roughly normal to the joint surface, and with propagation of tensile cracks, removable rock blocks are generated. The experimental results are simulated using PFC 2D. The numerical analysis simulates several aspects of rock mass cracking and the joint sliding processes around an opening: progressive fracture behaviors in a low joint angle rock model, abrupt initiation and propagation of tensile cracks and joint sliding in a high joint angle rock model (i.e. 60° to the horizontal), propagation of tensile cracks normal to the joint surface, generation of removable blocks in rock segments, an increase of lower hoop stress threshold inducing tensile fractures with a decrease in the joint angle, and an increase of the damage zone around the hole with a decrease in the joint angle.
- 45 - 2-03 Optimization of Alignment Considering Ride Comfort for Superimposition of Vertical and Horizontal Curves
First Author Abstract
Ju-Hwan Um Superimposition of horizontal and vertical curves [email protected] may hamper train ride comfort and running stability 82-31-460-5683 and inflate maintenance costs. However, designing a track plan without superimposed curves is difficult owing to fixed points that have to be either avoided Journal Info. because of geographical conditions or traversed so that existing structures are utilized. This article SCIE presents a method to optimize the alignment of IMechE rail and rapid horizontal curves to enhance train ride comfort and transit running stability when horizontal and vertical curves Vol. 225 No. 6 2011. 11 are superimposed in the case of railway construction/ renovation. An algorithm was developed to determine the combined range of radius–-transition curve lengths (R −. Lt) for feasible horizontal curves that pass fixed points; it was verified through a comparison with Kufver’'s iterative method using Inrail software. To determine the horizontal curves for optimal ride comfort when horizontal and vertical (convex) curves are superimposed under feasible R −. Lt boundary conditions, a solution algorithm was developed using the object function of ride comfort (PCT). Finally, the simplified analysis method using PCT was verified via vehicle/track interaction analysis.
- 46 - 2-04 Lateral Overturning Failures of Old Concrete Gravity Pier on Sandy Soils
First Author Abstract
In-Kyu Rhee This paper explores an overturning failure mechanism for an existing concrete gravity pier on soft sandy soil [email protected] beds in the event of a lateral push-over load. The pier 82-31-460-5369 had single horizontal cold joint in the middle of its height. The in-situ push-over experiments for the pier with/without vertical earth anchors between spread footing and rock beds showed different failure patterns Journal Info. against lateral load condition. In the unanchored system, no flexural cracking at the cold joint of the SCIE concrete pier developed, and the deviatoric stress of Soil Mechanics and the soil underneath the compression heel of spread Foundation Engineering footing was exceeded the limit of shear failure criteria locally. This leads to a global overturning failure by Vol. 48 No. 5 rotational lift of the pier-footing system but relatively 2011. 11 less stresses in the pier itself. While a lateral load is persistently increased in the anchored system, successive flexural cracking failure at cold joint was observed even after a local shear failure of the soils. The redistribution of stress equilibrium between the soil and the pier structure was continuously achieved as long as the tensile action of the anchor cable is active. The modified Drucker-Prager cap plasticity for sandy soil and the exponential tension softening/compression hardening laws for plain concrete were used in the nonlinear analyses. This study includes a discussion of the differences in the failure sequences of both unanchored and anchored systems in terms of their deviatoric/hydrostatic stress trajectories of selective soil/concrete elements undergoing a staggered local failure process.
- 47 - 2-05
Effect of Crack Width on Chloride Diffusion Coefficients of Concrete by Steady-State Migration Tests
First Author Abstract
Seung-Yup Jang The purpose of the present study is to explore the [email protected] diffusion characteristics of cracked concrete according 82-31-460-5302 to the width of cracks. Major test variables include crack width, concrete strength, fly ash addition, and maximum aggregate size. The diffusion characteristics Journal Info. have been measured by steady-state migration test. The present study indicates that the diffusion SCI coefficients do not increase with increasing crack Cement and Concrete widths up to the so-called “threshold crack width.” Research The threshold crack width for diffusion is found to Vol. 41 No. 1 – μ 2011. 1 be around 55 }80 m. Above this threshold value, the diffusion coefficients start to increase with crack width. A composite model with the introduction of “crack geometry factor” was derived to identify the diffusion coefficient in cracked concrete. It was shown that the crack geometry factor ranges from 0.067 to 0.206. Finally, the effects of concrete strength, fly ash addition and maximum aggregate size on diffusion coefficients are also discussed.
- 48 - 2-06 Experimental and Numerical Investigation on Dynamic Amplification Factors of an Urban Maglev Guideway
Corresponding Author Abstract
Seung-Yup Jang The Korean urban maglev project was initiated with [email protected] the intention of building a commercial line by 2012. 82-31-460-5302 An optimized guideway has been proposed and relevant tests are currently being conducted. However, the Dynamic Amplification Factor (DAF) for the Journal Info. maglev guideway has yet to be determined. As the maglev load is distributed rather than concentrated, SCIE further examination of dynamic behavior is required. KSCE Journal of Civil The objective of this study was to identify the DAF Engineering Vol.15 No.3 of the proposed urban maglev guideway via 2011. 3 moving-load analyses. For this purpose, a full-scale guideway girder test and a field test were conducted to identify the modal properties. A finite element model was then developed and verified against test results. Finally, moving load analyses were performed up to the maximum speed. Guideway deflection, longitudinal stresses, and support reactions were measured for various vehicle speeds−DAFs were thus computed. It was found that DAFs for maglev guideways are less than 2.5% at the maximum design speed. This implies that dynamic amplification need not be a severe consideration for the proposed maglev system.
- 49 - 2-07 Tilting Train-Induced Roadbed Response on the Conventional Line
First Author Abstract
Tae-Hoon Koh It is a fact that the straightening of track alignment is one of the undoubted ways to improve the train speed [email protected] on conventional lines, while that requires huge 82-31-460-5661 investment resources. Therefore, the operation of a tilting train as well as the minimum improvement of track is suggested as an effective and economical alternative way for the speed-up of conventional lines. Since a driving mechanism of tilting train is different from those of existing trains, in order to make sure JournalJournal of the Info.Korean its operation safety and stability on conventional line, the performance of track and roadbed must be preferentially evaluated on the conventional line. Journal of the Korean Furthermore, it is necessary to estimate the tilting Society for Railway -train-induced roadbed response in detail since the roadbed settlement can lead to the track deformation Vol. 14 No. 5 and even derailment. In this research, the patterns of 2011. 10 wheel load and lateral force were monitored and analyzed through the field tests, and the derailment coefficient and degree of wheel off-loading were calculated in order to evaluate the tilting train running safety depending on the running speeds(120km~180km) on the conventional line. Moreover, roadbed pressure, settlement and acceleration were also observed as tilting-train-induced roadbed responses in order to estimate the roadbed stability depending on the running speeds. Consequently, the measured derailment coefficient and degree of wheel off-loading were satisfied with their own required limits, and all of the roadbed responses were less than those of existing high-speed train (KTX) over an entire running speed range considered in this study. As a result of this study, the tilting train which will be operated in combination with existing trains is expected to give no adverse impact on the conventional line even with its improved running speed.
- 50 - 2-08 Traffic Safety & Passenger Comforts of a Suspension Bridge Considering Seismic Loads
First Author Abstract
Sung-Il Kim The estimation of traffic safety and passenger comfort [email protected] when the train is running on the bridge is a 82-31-460-5354 estimation unique to the railway bridge. The standards for such estimation are included in the Eurocode, the Shinkansen design criteria, and the design guideline of the Honam High-speed railway. The items are bridge responses including vertical displacement of bridge, vertical acceleration, and slab twist. In principle, a JournalJournal of the Info.Korean direct estimation based on the train responses has to take place. However, the estimation based on the Journal of the Korean bridge responses can be seen as an indirect estimation Society for Railway procedure for the convenience of the bridge designer. Vol. 14 No. 1 First, it is general practice that traffic safety can be 2011. 2 verified as a derailment coefficient or wheel load decrement The general method of estimating passenger comfort is to calculate the acceleration within the train car-body. Various international indexes have been presented for this method. In the present study, traffic safety and passenger comforts are estimated directly by bridge/train interaction analysis. The acceleration and wheel load decrement are obtained for the estimation of traffic safety and passenger comforts of a suspension bridge which has main span length of 300m. Also, the consideration of seismic load with simultaneous action of moving train is done for bridge/train/earthquake interaction analysis.
- 51 - 2-09 Centrifuge-Shaking Table Test for Seismic Performance Evaluation of Subway Station
First Author Abstract
Jin-Ho Kim When a certain magnitude earthquake occurs, serious [email protected] damage for human and properties is a major concern 82-31-460-5774 for most of the subway stations which were not applied for earthquake resistant design. Consideration and experimental verification for ground and structural
Journal Info. behavior based on soil-structure interaction relation are required to evaluate seismic performance of the Journal of the Korea subway station as embedded structures. For 1/60 Institute for Structural Maintenance inspection scaled subway station model, centrifuge modeling
Vol. 15 No. 3 shaking table test is performed using Kobe and North 2011. 5 ridge earthquakes. Compare to displacements and moments of the underground and structure obtained by soil response analysis and response displacement method based on experimental results, this paper shows how to evaluate seismic performance of subway station.
- 52 - 2-10 Investigation of the Maintenance Criteria for the Rail Surface Defects in High-Speed Railways
First Author Abstract
Sin-chu Yang The rail surface defects can cause the high impact [email protected] load on the track and lead to the progress of the 82-31-460-5301 rail fatigue damage and the rail break. In case of the rail break, there is a great deal of risk for derailment, and thus the maintenance criteria for the rail surface defects are of great importance. In this study, using the dynamic train-track interaction JournalJournal of the Info.Korean analysis program, the impact wheel loads and rail bending stresses according to the depths of the Journal of the Korean surface defects have been calculated with the input Society for Railway data of the rail surface irregularities measured at 43 Vol. 14 No. 6 spots with surface defects in the ballasted track of 2011. 12 high-speed railway. Considering the irregularity of track geometry, the allowable limits of wheel load and rail bending stress have been set, and the maintenance criteria for the rail surface defects was suggested by analyzing the relationship of the maximum values of wheel load and rail bending stress versus depth and width of rail surface defect. The analysis results suggest that the allowable depth of the irregularities is determined approximately 0.2mm from the limit of the impact wheel load.
- 53 - 2-11 Determination of Upper Limit of Rail Pad Stiffness for Ballasted and Concrete Track of High-Speed Railway Considering Running Safety
First Author Abstract
Sin-chu Yang In this study, the methodology to determine the [email protected] upper limit for stiffness of rail pad for the 82-31-460-5301 ballasted and concrete track in high-speed railway in the viewpoint of running safety, considering the dynamic characteristics of train and track and the operation environment. For the track irregularity, one of the most important input parameters for JournalJournal of the Info.Korean train-track interaction analysis, the reference vertical track irregularity PSDs(power spectral Journal of the Korean densities) for the ballasted and concrete track in a Society for Railway wide range of frequencies were proposed based on those presented in France and Germany and that Vol. 14 No. 6 obtained from the measured data at Kyeong-Bu 1st 2011. 12 phase high-speed railway line. Using these reference PSD models, the input data for the vertical track irregularity data were regenerated by random generation process, and then, the wheel load reduction rates according to the stiffness of the rail pads have been calculated by the train-track interaction analysis technique. Finally, by comparing the wheel load reduction rates calculated with the derailment criteria prescribed in the Korean standards for railway vehicle safety criteria, the upper limits for the stiffness of rail pad have been proposed.
- 54 - 2-12 Evaluation of Train Running Safety During Construction of Temporary Bridge on Existing Railway
First Author Abstract
Ki-Young Eum Installing the temporary bridge after excavating the [email protected] railway requires installing movable cross beam, but 82-31-460-5680 as it doesn’ requires isolating the catenary or cutting the rail, it’ applicable to double-track with frequent operation. In this study, a displacement meter was placed on temporary bridge to monitor the displacement pattern in curve section (R400) completed using JournalJournal of the Info.Korean temporary bridge method, and wheel load, lateral pressure and derailment coefficient were measured to Journal of the Korean Society for Railway evaluate the load imposed on track and the stability in curve section (R400) for quantitative evaluation of Vol. 14 No. 3 training running safety. As a result of the measurement, 2011. 6 when trains passing over a temporary bridge, the maximum value of Wheel load and Lateral Force is analyzed as the 51% and 81% of standard level according to foreign country’ performance tests, There is no trouble with stability analysis in Wheel load and Lateral Force occurring. Additionally, Wheel load and Lateral Force considered as the safety standard are tested 49% of limiting value regardless of trains, which the norm value quite well, there is no problem with train running.
- 55 - 2-13 An Experiment and Analysis of Precast Concrete Baseplate on Bimodal Tram Dedicated Bridge
Corresponding Author Abstract
Hee-Taek Yoon To purpose of this study is to develop the new type [email protected] of precast concrete baseplate which is only for 82-31-460-5383 bimodal tram. The experiments with real size specimens, which are hollowed precast baseplate, prove the efficacy of new designed baseplate by comparing with the result of RCAHEST. Through Journal Info. tests progressed according to different loading
Journal of the Korea locations, the specimens show the stability by the Institute for Structural safety factor of 8~9. Also the results of RCAHEST Maintenance inspection that is the nonlinear finite element method program, Vol. 15 No. 2 appropriately estimate the occuring crack on concrete, 2011. 3 yielding reinforcement and ultimate behavior at failure.
- 56 - 2-14 A Study on the Basic and Compression Characteristics of Lightweight Waste for Use as Fill Materials
First Author Abstract
Sung-Jin Lee This is a fundamental research on use as fill [email protected] material of lightweight waste such as bottom ash and 82-31-460-5072 tire shred. We carried out the test for particle size distribution, specific gravity, density, shear strength, permeability and vertical compression settlement, considering water content change and temperature Journal Info. effect of several waste materials. Bottom ash, which is lighter than soils, has similar permeability and Transactions of particle size distribution to those of weathered soils. Korean Geotechnical But permeability may differ depending on the Society Vol. 27 No. 5 particle size distribution. The shear strength aspect of 2011. 5 bottom ash and tire shred mixed materials are similar to that of natural fill materials. In the 1-D vertical compression settlement test, we could be assured that bottom ash and tire shred mixed materials showed similar compression settlement to that of sandnunder actual vertical stress. Furthermore, materials including bottom ash showed smaller compression settlement than that of weathered soils in the long-term settlement test under wetting and freezing-thawing condition.
- 57 - 2-15 An Experimental Study on Local Stability of Eco-Block
Corresponding Author Abstract
Su-Hyung Lee In this study, computation method of tensile load [email protected] which develops in tie-bar of reinforced earth, 82-31-460-5399 connection strength between tie-bar and eco-block and shear strength of the interface between two eco-blocks were verified by experiments. According to the test results of connection strength test, peak Journal Info. tensile load of D13 deformed bar were close to allowable tensile load of it for situation of infill Transactions of Korea with soil. Connection strengths of D10 and D13 Academia-Industrial deformed bars were greater than the allowable tensile Cooperation Society load of those respectively for situation of infill with Vol. 12 No. 6 concrete. According to the test results of shear 2011. 6 strength of the interface between two eco-blocks, shear resistance parameters, and ﾞ were evaluated as 1.7kN/m and 27.6 respectively.
- 58 - 2-16 Development of FBG Accelerometer for Railway Tunnel Vibration
First Author Abstract
Su-Hyung Lee For the safety management of tunnel, effective [email protected] measurements should be continuously carried out. 82-31-460-5399 Most of sensors currently being applied for tunnels measure only the local status, thus many of them are needed to monitor an entire tunnel. For the railway tunnel where trains of same conditions are JournalJournal of the Info.Korean regularly operated, dynamic responses of tunnel structure to train operations can be a good index to Journal of the Korean estimate the deformation of tunnel structure in wide Society for Railway area. Meanwhile, the electromagnetic interference Vol. 14 No. 4 caused by overhead centenary in railway tunnel 2011. 8 obstructs the use of electric-based sensors. In this study a brand new accelerometer using FBG optical fiber sensors is developed to solve these problems. Sensitivity and capacity of the accelerometer are enhanced with effective structural design of its components and verified with laboratory tests. A case history where the developed accelerometers were applied to a safety monitoring system of a high-speed train tunnel is presented. The performances of the developed accelerometers are validated from the measured acceleration data.
- 59 - 2-17 Evaluation of Dynamic Stability for Structural Bar Reinforced Precast and Prestressed Retaining Wall for Moving Train Load
First Author Abstract
Il-Wha Lee The precast production has many advantages by fast [email protected] construction period, labor-saving and high quality. In 82-31-460-5326 recent years, the application of the precast product has been increased in the earth retaining wall field. This paper presents the results of the numerical analysis that was carried out to evaluate the dynamic Journal Info. stability of precast and prestressed earth retaining wall under moving train load. The two-dimensional Journal of the Korea FEM analysis was used to the numerical analyses. Institute for Structural The train load to act on trackbed is combined by Maintenance inspection the real measured roughness phase angle and Vol. 15 No. 5 quasi-static load. The dynamic stability is analysed 2011. 9 by the displacement, acceleration and stress under moving train load at each specified location. The results of the analysis show that the precast and prestressed retaining wall has very stable capability for the railway.
- 60 - 2-18 Dynamic Response Characteristics for Two-Layered Trackbed Structure by Train Load
First Author Abstract
Il-Wha Lee It is difficult to clarify the dynamic response [email protected] characteristics of trackbed because of various 82-31-460-5326 environmental conditions. However, track irregularity be affected by ununiformed bearing capacity and its dynamic response, study for dynamic response characteristics is required to investigate the cause of JournalJournal of the Info.Korean track irregularity and countermeasure. In this paper, the response variation for dominant frequency and Journal of the Korean vibration energy by trackbed structure and material Society for Railway stiffness are investigated. The analysis section is two Vol. 14 No. 2 layered ground structure that is comprised of 2011. 4 trackbed and soft rock. This structure amplifies the energy of dominant range easily. It is evaluated to affect track irregularity on comparing by theoritical, analytical and empirical method for dynamic response of the trackbed.
- 61 - 2-19 Reduction of Shear Strength of Railway Roadbed Materials with Freezing-Thawing Cycle
First Author Abstract
Chan-Yong Choi In seasonal frozen areas with climatic features, which [email protected] have a temperature difference in the winter and 82-31-460-5317 thawing season, changes of mechanical properties of the soil in the zone could be seen between the freezing and thawing surface. In particular, in soil with many fine particles, a softening of the roadbed Journal Info. usually occurs from frost and thawing actions. The lower bearing capacity is a rapidly progressive the Transactions of softening of roadbed, and occurred a mud-pumping Korean Geotechnical by repeated loading. In this study, the three kind of society sandy soil with contents of fine particles were Vol. 12 No. 7 conducted by directly shear box test with the number 2011. 7 of cyclic in freeze-thawing and the water content of soil. Subsequently, the relationship between the shear strength and freeze-thaw cycling time was obtained. The shear strength was decreased with the increase of the freeze-thaw cycling time. A shear stress deterioration of the soil with power function modal is proposal.
- 62 - 2-20 A Comparative of Ground Stress with Difference of The Fixed Point Loading and Moving Wheel Loading
First Author Abstract
Chan-Yong Choi In this paper, it was compared the characteristics of [email protected] the stress and settlement that occur from a track on 82-31-460-5317 the ground using a model test and has quantitatively analyzed the difference based on stress path and effect of the rotation of principal stress. Under identical roadbed conditions, the settlement generated JournalJournal of the Info.Korean by moving wheel loads were found to be 6 times and 3 times larger than that from static loads and Journal of the Korean cyclic loads, respectively. The deviator stress Society for Railway affecting shear deformation and the length of stress Vol. 14 No. 1 path generated by moving loads were twofold or 2011. 2 greater increase that those by static loads. Furthermore, the stress path generated by moving loads was approached more closely to Mohr-Coulomb failure criteria compared to that by static loads. Also, it was found that ballasted track was occurred about 60% of maximum stress at 40° of the rotation angle of principal stress and was affected with rotation of principal stress with moving wheel loading condition.
- 63 - 2-21 Evaluation of Correlation between Strain Mudulus (Ev2) and Deformation Modulus (ELFWD) Using Cyclic Plate Loading Test and LFWD
First Author Abstract
Chan-Yong Choi In this study, it conducted a compaction quality [email protected] control test in 29 domestic construction sites and 82-31-460-5317 investigated the relationship between classical method (Cyclic Plate bearing test) and LFWD test with subgrade materials which consist in sandy soil and gravelly soil. According to the test results, the most JournalJournal of the Info.Korean of soil types were mostly satisfied with specification criterion and gravelly soils were easily satisfied with Journal of the Korean values over 3 times greater than specification criterion. Geosynthetics Society In term of the correlation relation of soil modulus Vol. 10 No. 3 with the two compaction quality control test methods, 2011. 9 it is shown that the sandy soil types were a good correlation, while gravelly soil types with a high stiffness materials were indicated less correlation. After the compensation for stress condition, a linear regression for elastic modulus were higher correlation.
- 64 - 3-01 Conceptual Design for HTS Coil in Superconducting Electromagnet for Maglev
First Author Abstract
Chang-Young Lee This study deals with a conceptual design for a high [email protected] temperature superconductor (HTS) coil fabricated 82-31-460-5525 with YBCO wire in a prototype HTS-electromagnet (HTS-EM) model for the electromagnetic suspension (EMS)-based Maglev. Because the size of the HTS Journal Info. coil and the power it consumes during operation are very critical factors in designing the HTS-EM, we SCI focused on the number of coil turns and the IEEE Tran. on Applied operating conditions needed to generate the required Superconductivity magneto-motive force (MMF) effectively. The Vol. 21 No. 3 winding geometry of the sample HTS coil with the 2011. 6 largest Ic value was selected for use in this study. To determine the operating condition corresponding to the number of coil turns, we produced the operating profile for the load current of DC current source and the Ic value of HTS coil. From the profile, the optimal number of coil turns to minimize the operating power is determined to be in the range of 1200 to 1400 turns. And the HTS coil should be operated with the current of 37 to 43 A at the cooling temperature of 73 to 76 K.
- 65 - 3-02 Characteristics of Persistent-Current Mode of HTS Coil on Superconducting Electromagnet
First Author Abstract
Chang-Young Lee This paper investigates the way in which the [email protected] levitation gap of an electromagnetic suspension 82-31-460-5525 (EMS) system affects the current decay rate of superconducting electromagnet (SC-EM) operated in persistencecurrent mode (PCM). Using inductance Journal Info. analyzed from the magnetic circuit of an EMS model, the current decay rate caused by the variation SCI in the levitation gap was simulated. In order to Physica C experimentally verify the simulation results, we Vol. 471 No. 21-22 fabricated a small-scale EMS model with SC coil 2011. 11 operated in PCM and measured the current decay rates at different levitation gaps. The result showed that the presence of iron core provides a significant benefit in the PCM performance of SC coil, but the benefit decreased as the levitation gap increases. This study revealed that the increased levitation gap of the EMS model with the SC-EM could negatively affect the design of SC-EM operated in PCM.
- 66 - 3-03 Improvement of Thrust Force Properties of Linear Synchronous Motor for an Ultra-High-Speed Tube Train
First Author Abstract
Hyung-Woo Lee In case of high-speed maglev trains, the propulsion [email protected] force of their linear synchronous motor (LSM) is an essential performance element since the LSM is 82-31-460-5426 responsible for both the propulsion and levitation of the train. A large thrust force ripple causes vibration, noise and severe levitation disturbance during the Journal Info. train operation. Because of these reasons, efforts must be made to reduce the thrust ripple of the SCI LSM for propulsion and levitation. In this study, a IEEE Transactions on method to decrease the thrust force ripple that causes Magnetics the noise, vibration, and levitation disturbance generated during the high-speed operation of the 700 Vol. 47 No. 11 km/h ultra-high-speed tube train’'s LSM was 2011. 11 investigated. In this method, the module phase set shift (MPSS) was applied. If the MPSS method is applied, the position of each field magnet module of the LSM changes as much as MPSS value relative to the reference load angle. To precisely calculate the total thrust force that occurs due to the position changes, thrust force mapping (TFM) method was applied to each field magnet module, and the generated total thrust force of the LSM were accurately obtained. Through this study, a method of reducing the thrust force ripple without considerable reduction of the LSM’'s average thrust force was presented.
- 67 - 3-04 Parameter Design of IPMSM With Concentrated Winding Considering Partial Magnetic Saturation
First Author Abstract
Hyung-Woo Lee The interior permanentmagnet synchronousmotor [email protected] (IPMSM) is usually applied to the traction motor in 82-31-460-5426 the hybrid electric vehicle and the electric vehicle due to its high-power density and wide speed range. In this paper, the IPMSM with concentrated winding Journal Info. for a 110 cc electric motorcycle is introduced. Its design was improved for high efficiency and a wide SCI speed operation range. The output characteristics IEEE Transactions on were also analyzed according to the partial magnetic Magnetics saturation of the shoe and web in many variables. Vol. 47 No. 10 2011. 10 Because partial magnetic saturation affects the harmonics and the eddy current loss of the permanent magnet, it was confirmed that the output characteristics of the motor significantly changed. As a result, the new shape and the design parameters for which the partial magnetic saturation was considered were obtained. Higher level efficiency and a wider operating range than with the base model were confirmed.
- 68 - 3-05 Thrust Performance Improvement of a Linear Induction Motor
First Author Abstract
Hyung-Woo Lee The end effect of a linear induction motor (LIM) [email protected] has been known for several decades, especially in 82-31-460-5426 high speed operation. The exit part of the primary is not dealt as extensively as the entry part because of its minor effect. However, the exit part is one of the keys to weaken the dolphin effect, which occurs in Journal Info. high speed operation. In this paper, the concept of the virtual primary core is introduced, and SCIE chamfering of the primary outlet teeth is proposed to Journal of Electrical Engineering & Technology minimize the longitudinal end effect at the exit zone. Vol. 6 No. 1 For this, LIM for the high-speed train is designed 2011. 1 and analyzed by using finite element method. Results confirm that chamfering can improve thrust performance effectively.
- 69 - 3-06 Magnetic Interference on the Infrastructure for a Super-Speed Tube Train
First Author Abstract
Hyung-Woo Lee The super-speed tube train was introduced to [email protected] increase the speed of ground transportation. It 82-31-460-5426 levitates magnetically and runs in a partial vacuum tube, which significantly reduces air resistance. However, strong magnetic force sufficient to propel the massive train can affect the infrastructure. The Journal Info. induced eddy current produces joule heat, and raises the inside temperature of the girder, which might SCIE lead to electrochemical corrosion on the girder, Journal of Electrical thereby weakening its durability. In this paper, the Engineering & Technology authors analyzed the magnetic flux and induced eddy Vol. 6 No. 3 current in the reinforced concrete girder by using 2011. 5 three-dimensional FEM, particularly by varying the number of reinforcing steels of the upper flange of the girder to the condition of almost the same flexural strength and reinforcing steel amount.
- 70 - 3-07 License Plate Extraction Method for Identification of Vehicle Violations at a Railway Level Crossing
First Author Abstract
Bong-Kwan Cho The primary cause of most railroad accidents is [email protected] vehicle entry into railway level crossings despite warning messages. To identify drivers who violate 82-31-460-5439 railway level crossing regulations, vehicle license plate recognition can be applied at railway level crossings. The purpose of this paper is to present an effective method for extracting the license plate Journal Info. region from vehicle images taken at railway level crossings. The method proposed in this paper uses SCIE the variation in the gray-level values across the image of a license plate. For license plate region International Journal of Automotive Technology extraction, the character region is first recognized by identifying the character width and the difference Vol. 12 No. 2 between the background region and the character 2011. 4 region. The license plate region is then extracted by finding the inter-character distance in the plate region. In addition, the license plate type is identified by the difference in the gray-level value between the background region and the character region. The proposed method is effective in solving the current challenges in extracting the license plate region from the damaged frames of license plates issued for domestic use, including new types of license plates. According to the experimental results, the proposed method yields a high extraction rate of 99.5% for vehicle license plates.
- 71 - 3-08 Implementation of a Condition Monitoring System for Mold Transformers in DC Substations
First Author Abstract
Young Park The mold transformer is a complex and critical [email protected] component of DC substations in Metro system. In 82-31-460-5424 this paper, a cost effective and intelligent condition monitoring system for mold transformers in DC substations was developed. This paper also provides an overview of the management program using PD Journal Info. (partial discharge) data on mold transformers. Prior to application of the proposed system to Metro DC Transactions of Korea substations, experiments were performed at the metro Institute of Electrical line substation located in Seoul and presented case Engineers studies for the use of the intelligent condition Vol. 60 No. 9 monitoring system for mold transformer in DC 2011. 9 substations. The experiment results indicated that the developing system can be need in helping mange the risk of unexpected failure of mold type transformers.
- 72 - 3-09 Development of an Arc Detector Assessment System by Loss of Contact Between Pantograph and Contact Wire in Electric Railway
First Author Abstract
Young Park The objective of this paper is to discuss technologies [email protected] on assessing reliability of arc detectors by composing 82-31-460-5424 a system that generates and simulates occurrence of arc caused by loss of contact between pantographs and contact wires in a laboratory condition. In order to establish the arc simulator, a device that generates Journal Info. light having the bandwidth of arcs that occur between carbon-metal. The simulator was designed Transactions of Korea under conditions of EN 50317 and simulations were Institute of Electrical Engineers conducted using the developed device. According to the results, it was possible to conduct certification Vol. 60 No. 11 tests following regulations of international standards 2011. 11 and the precision of the simulator was satisfactory. The proposed arc detector assessment system is expected to enhance precision of current collection quality performance assessment methods at high-speed lines and conventional lines while being referred as fundamental technologies for development of detectors suiting international conditions.
- 73 - 3-10 Analysis of Iron-filings Trapping Characteristics on Concrete Slab Track using Permanent Magnet
First Author Abstract
Chan-Bae Park Iron fillings which were accumulated around the rail [email protected] was often the cause of abnormal signal in case of 82-31-460-5427 signaling equipment using rail as transmission line. Iron fillings were generated on curved section of railroad due to the friction between rail and wheel, and metro line company urged to find the way to JournalJournal of the Info.Korean remove these iron fillings, because these were often the cause of abnormal signal. Magnetic device for Journal of the Korean trapping iron fillings around concrete slab tracks is Society for Railway introduced. The characteristics of magnetic device Vol. 14 No. 4 were analyzed using basic design and numerical 2011. 8 analysis method. Magnetic device for trapping iron fillings were examined for application to the train which were operating in commercial line.
- 74 - 3-11 A Study on an Airgap Control System in a Rotary-small-scaled Linear Induction Motor for Railway
First Author Abstract
Chan-Bae Park In general, it is important to operate the airgap [email protected] length uniformly for improving the system efficiency 82-31-460-5427 independent of the flatness of the reaction plate in a railway propulsion system by a linear induction motor (LIM). And it is possible to operate the LIM propulsion system efficiently without a change of the JournalJournal of the Info.Korean LIM capacity through the airgap length control on the sloped rail. So, in this research, authors Journal of Energy and introduce an airgap control system to control the Power Engineering airgap length which depends on the flatness of the Vol. 5 No. 12 secondary reaction plate when the LIM is operated, 2011. 12 and designs a rotary small-scaled LIM and its airgap control system before manufacturing the real system. Then, authors analyze some characteristics of the LIM (thrust and normal force, input current, efficiency and power factor), and through the LIM control modeling, authors finally analyze an effect of the airgap-length control of the LIM by the airgap control system.
- 75 - 3-12 Development of a Series Hybrid Propulsion System for Bimodal Tram
First Author Abstract
Chan-Han Bae Bimodal tram is designed to run on a dedicated path [email protected] in automatic mode using a magnetic track system in 82-31-460-5417 order to realize a combination of the accessibility of a bus and the constant regularity of a railroad. This paper presents design and test results of the series hybrid propulsion system of the bimodal tram on JournalJournal of the Info.Korean both test track and public road, which uses CNG (Compressed Natural Gas) engine and Lithium The Transactions of polymer battery pack. This paper describes the the Korean Institute of real-time data measuring equipment for the series Power Electronics Vol. 16 No. 5 hybrid propulsion system of the bimodal tram. Using 2011. 10 this measurement equipment, the performance of the prototype vehicle's driving on test track and public road was verified and the fuel consumption and the efficiency of CNG engine have been investigated.
- 76 - 3-13 Harmonic Frequency Analysis of Interlocking System for Rolling Stock Operation in Electrical Railroads
First Author Abstract
Jong-Hyen Baek Electrical Railroads provide electric power, which [email protected] can operate vehicles, via feeder wires. And the 82-31-460-5441 supplied current returns to the transformer substation through lines and ground net. The used load current depending on the operation of rail vehicles in the electric railway sections returns to the substation Journal Info. through a track which is a return circuit. The load current contains harmonics because of the power Transactions of Korea Academic-Industrial conversion equipment used in rolling stocks and such Cooperation Society harmonic currents should not affect train control system. In this paper we present the test result in Vol. 12 No. 8 2011. 8 order to verify that the harmonics produced by the operation of rail vehicles in the newly built electric railway sections can affect interlocking systems. The test in question was performed in a linking section that trackside equipment under railway operating conditions and interlocking are linked in order to identify whether or not the interlocking fitted in a signal machine room can be affected by harmonics according to railway operation.
- 77 - 3-14 Analysis of Return Current for Rolling Stock Operation on Electrical Railroads
First Author Abstract
Jong-Hyen Baek Electrical Railroads provide electric power, which [email protected] can operate vehicles, via feeder wires. And the 82-31-460-5441 supplied current returns to the transformer substation through lines and ground net. The return current, related to signal, power and power line, and track circuit systems, is one of the most important Journal Info. component in the electric railway. Therefore, to prevent system faults and breakdown according to Transactions of Korea unbalance and overcurrent of the return current, Academic-Industrial various and detailed analysis for the return current Cooperation Society are needed. In the paper, we present measurement Vol. 12 No. 9 and analysis manners in real environment and 2011. 9 evaluate its safety. For analysis, we utilize the measured values of return currents measured in track circuits in electric railway. we expect that this research plays a key role to the related fields.
- 78 - 3-15 Analysis of Interoperability Test between a Different Kind of Train Control System
First Author Abstract
Jong-Hyen Baek In this paper, for the purpose of improving the [email protected] future domestic train control systems and securing 82-31-460-5441 interoperability according to the global development trends of train control systems, we present the test results of interoperability between wayside train control system installed in existed line, and the Journal Info. onboard train control system. Due to the safety-critical characteristics of train systems, the site Journal of the Korea test in the section where the wayside equipment is Entertainment Industry Association installed, leads to a danger against safety. Therefore, Vol. 5 No. 1 by way of constructing a simulation environment of 2011. 3 train control systems, we confirm the T/R data systems of the equipment for interoperability and test the interoperability by applying these systems to onboard equipment.
- 79 - 3-16 Vehicle Running Characteristic Simulator Using Induction Motor
First Author Abstract
Yeun-Sub Byun In this paper, we propose vehicle running characteristic [email protected] simulator. The developed simulator is configured by 82-31-460-5437 two induction motors which are directly coupled with each other. One motor is to simulate the vehicle drive and another motor is to simulate the vehicle dynamic load including running resistance, gradient Journal Info. resistance and adhesive characteristics between rail and wheel. The running characteristics of vehicle are Transactions of Korea Institute of Electrical modeled by numerical formulas. These are programed Engineers by software of embedded controller. Thus, it is Vol. 60 No. 10 possible to change several running characteristics 2011. 10 during the running test freely and instantly. To evaluate the feasibility of the simulator, the experiments on slip and adhesion coefficient are performed. Additionally the adhesion control and speed control of vehicle are tested with simulator. Experimental results show that the simulator can produce the driving characteristics similar to the vehicle system.
- 80 - 3-17 Evaluations of the Robustness of Guidance Controller for a Bimodal Tram
Corresponding Author Abstract
Yeun-Sub Byun This paper is concerned with the robustness [email protected] evaluations of the guidance controller for a bimodal 82-31-460-5437 tram which is being developed by the Korea Railroad Research Institute (KRRI). The bimodal tram is an all-wheel steered multiple-articulated vehicle as a new kind of transportation vehicle. This Journal Info. vehicle has to be equipped with an automatic guidance system. In [1], such a controller has been Transactions of Korea recently proposed. However, since the performance is Institute of Electrical affected by weight change of the vehicle due to Engineers number of the passenger, model parameter Vol. 60 No. 10 uncertainties depending on the state of friction and 2011. 10 the elasticity of the tire, and a typhoon, the controller designed must be examined with these conditions. As expected, because the vehicle dynamics is highly nonlinear, for the sake of investigating the robustness of the controller we compose two simulation ways based on the vehicle models which are implemented by the ADAMS and the MATLAB/LabVIEW tool boxes. Different uncertainties and a typhoon disturbance have been considered for the simulation conditions. Simulation results are shown.
- 81 - 3-18 The Design and Analysis of Recognition Structure for Absolute Train Positioning System of High-speed Maglev Train System
First Author Abstract
Kyung-Ho Shin For the train positioning system currently applied in [email protected] high-speed MAGLEV train systems, it is classified 82-31-460-5488 into absolute positioning systems which discontinuously detect train positions, and relative positioning systems which continuously detect train positions. In this paper we analyze the configuration model and the JournalJournal of the Info.Korean numerical model of the absolute positioning system applied in TRANSRAPID which is a representative Journal of the Korean high-speed MAGLEV train, and design the two Society for Railway configuration models specific to the recognition Vol. 14 No. 2 structures of absolute positioning systems. We also 2011. 4 verify the compatibility of the design models of absolute positioning system through simulation using MATLAB and propose the optimal configuration model of absolute positioning systems for high-speed MAGLEV train system.
- 82 - 3-19 A Study on the Reliability/Safety Assessment and Improvement of USN Gateway for Train Control
First Author Abstract
Duc-Ko Shin The recent development of USN (Ubiquitous Sensor [email protected] Network) technology has broadened its applications 82-31-460-5442 to many fields of industry. The USN technology enables the system to monitor and control the status of distributed sensor nodes based on the low-powered communications. Applying the USN in the train control domain, the operational efficiency can be JournalJournal of the Info.Korean enhanced, where the reliability and the safety of the Journal of the Korean system are the key challenges. This paper suggests Society for Railway the system design for evaluating and improving the Vol. 14 No. 5 reliability and safety of the gateway, which is a 2011. 10 USN component that manages the radio network among the sensors and collects the information from them. For this purpose, the reliability and the level of safety integrity of a general gateway have been predicted quantitatively and the supplementary design has been proposed for the selected week points. The verification on the reliability and the safety of the improved gateway according to the related standards has been followed. With the results of the study, the applicability of USN gateway for train control systems has been reviewed.
- 83 - 3-20 Performance Evaluation of Wireless Sensor Networks in the Subway Station of Workroom
First Author Abstract
Tea-Ki An In order to monitor internal risk factors such as fire, terror, etc. on the subway station, the surveillance [email protected] systems using CCTV and various kinds of sensors 82-31-460-5714 have been implemented and recently, introduction of surveillance systems using an advanced IT technology, sensor network technology is tried on several areas. Since 2007, Korean government has made an effort to develop the intelligent surveillance and monitoring system, which can monitor fire, intrusion, passenger Journal Info. congestion, health-state of structure, etc., by using wireless sensor network technology and intelligent Transactions of Korea video analytic technique. For that purpose, this study Academic-Industrial carried out field wireless communication environment Cooperation Society test on Chungmuro Station of Seoul Metro on the basis of Zigbee that is considered as a representative Vol. 12 No. 7 wireless sensor network before field application of the intelligent integrated surveillance system being 2011. 7 developed, arranged and analyzed and ZigBee based wireless communication environment test results on the platform and waiting room of Chungmuro Station on this paper. Results of wireless spectrum analysis on the platform and waiting room showed that there is no radio frequency overlapped with that of Zigbee based sensor network and no frequency interference with adjacent frequencies separated 10MHz or more. As results of wireless data transmission test using ZigBee showed that data transmission is influenced by multi-path fading effect from the number and flow rate of passengers on the platform or the waiting room rather than effects from entrance and exit of the train to/from the platform, it should be considered when implementing the intelligent integrated surveillance system on the station.
- 84 - 3-21 Development of a Simulator for Radio Propagation Path Loss in Tunnel at 18GHz
First Author Abstract
Tea-Ki An In this paper, the radio propagation path loss [email protected] prediction simulator in tunnel was developed. It used 82-31-460-5714 a image theory method for analysing precise radio propagation path. And it can predict radio propagation path loss in straight and curved tunnels. The simulator can plot realtime radio propagation paths Journal Info. using various parameters which was input by user. And it can simulate from changing transmitter and Transactions of Korea receiver positions. The predicted path loss of Academic-Industrial Cooperation Society simulator was compared with the measurements in Chunhyun tunnel and confirmed the validity. Vol. 12 No. 4 2011. 4
- 85 - 3-22 Intelligent Video Surveillance System using RFID Technology
First Author Abstract
Tea-Ki An Lots of problems are emerged on the conventional [email protected] surveillance systems at urban railway infrastructure. 82-31-460-5714 Many projects and research activities have been processing on those problems. Moreover, The interest in Intelligent Video Surveillance System that provides accident prevention and safe driving in urban railway Journal Info. service is dramatically increasing. This paper represents a drawback of existing studies and introduces a new The Institute of Webcasting Internet solution using RFID TAG technology to improve the and Telecommunication existing problems. Finally, it describes the practice Vol. 11 No. 1 test of automatic notification system based 2011. 2 USN(Ubiquitous Sensor Network) for a dangerous situation.
- 86 - 3-23 A Study on a Configuration of the Load Characteristic 5 Evaluation Device Using Hydraulic Power for the Analysis of the Tilting Kinetic Mechanism
First Author Abstract
Jun-Ho Lee In this paper a configuration of the load evaluation [email protected] device for the tilting actuator using hydraulic power 82-31-460-5040 is presented, which makes it possible to measure the force action on the tilting actuator. It is possible to measure only current using the conventional electro-mechanical actuator when the bogie is in the Journal Info. process of the tilting. This makes impossible to measure the force acting on the tilting actuator. In Transactions of the order to overcome this problem a kinetic mechanism Korean Society for test system using hydraulic cylinder is proposed. The Noise and Vibration Engineering system are consisted of hydraulic cylinder for the tilting actuation, control system to control hydraulic Vol. 21 No. 12 power, sensors to measure for force and 2011. 12 displacement and monitoring system for the user interface.
- 87 - 3-24 Development of the Operation Simulator for the PRT System
First Author Abstract
Rag-Gyo Jeong A time based software simulator for the PRT system [email protected] operation is presented. The purpose of the simulator 82-31-460-5725 is to estimate the passenger transportation performance of the PRT system. In this paper, it is presented how the system is modeled in the simulator to estimate passenger transportation performance and the running Journal Info. algorithm of the modeled subsystem. An application sample is also presented to find the system's design Transactions of Korea Institute of Electrical parameter to satisfy the transportation needs. Engineers Vol. 60 No. 11 2011.11
- 88 - 3-25 A Study on Establishment of Signaling Systems to Speed up Conventional Railway
First Author Abstract
Rag-Gyo Jeong Studies suggested an increase in the competitiveness [email protected] and roles of mainline railways like speed and accessibility improvement, as a fundamental direction 82-31-460-5725 of the National Transport Network Plan. At this point, topics presented especially for strengthening the role of human and environment centered transportation: as to the greatly improved speed Journal Info. competitiveness, there are an operational speed above 180km/h ~ 200km/h and traveling within 2 ~ 3 Transactions of Korea hours among big cities. As to accessibility Institute of Electrical improvement, there are accessibility to main railway Engineers stations within 30minutes, and the improvement of accessibility, safety, eco-friendliness, amenity etc. As Vol. 60 No. 9 a part of these suggestions, field specific plans were 2011. 9 proposed for the establishment of expressed mainline railway network in Korea such as train's, civil structures, trolley lines etc. In this paper we analyzed the conventional lines and systems to figure out whether to change details in terms of H/W of signaling system. Additionally, we reviewed the compatibility or difference of signalling system depending on train's speed. With this result, we deduced the number of virtual blocks specific to the speed of 180km/h, 200km/h and 230km/h, which were showed for the speed improvement considering each variable like blocks, braking distance etc. In this way, we suggested the railway signal system establishment plan considering safety operation.
- 89 - 3-26 Development of Door Control Unit for the Electric Plug-in Door of Subway Train
First Author Abstract
Eui-Jin Joung The Electric Multiple Unit (EMU) has many types of [email protected] door system such as sliding door, plug door etc.al, 82-31-460-5448 according to customer's requirements. The sliding door is widely used in Korea but has weak point in the noise problem. In the low operation speed, the noise coming from outer side of the EMU is not an Journal Info. important factor. As the speed is higher than before, noise is increased and make a problem. The main Transactions of cause of noise is the imperfect air tightness in the Instituteof Electronics EMU. The plug door system has advantages for the Engineers of Korea noise reduction characteristic in the high speed area. Vol. 48 No. 4 We have been developing electric plug-in door. The 2011. 7 door is controlled by Door Control Unit (DCU) following the order of Automatic Train Protection (ATP) that is a kind of train signalling system. DCU has to simultaneously open and close the doors and the operation of it is related to the passengers safety. So DCU is a safety device that is important to reliability and safety. DCU is composed of several devices of control, motor driving, Input/Output, communication and power. In this paper, we will describe the functions, characteristic, requirement, subsystem, and test results of DCU used for the electric plug-in door.
- 90 - 3-27 An Analysis on Rise of Rail Potential and A Study on Control Method for It in DC Feeding System
Corresponding Author Abstract
Ho-Sung Jung Nowadays, in metropolitan railroad, DC feeding [email protected] system is being generally applied. In order to reduce 82-31-460-5116 damages of electro-chemical corrosion caused by stray current and leakage current, in DC feeding system, rail is used as negative-polarity return conductor for traction load current. However, it has Journal Info. problem of rail potential increase and there are no adequate measures to prevent it in domestic. In this Transactions of Korea paper, we presented fundamental theory and related Institute of Electrical Engineers standards about rail potential increase. And then, we analyzed field testing data and simulated a variety of Vol. 60 No. 3 operations by using PSCAD/EMTDC as an analysis 2011. 3 program of power system. In addition, voltage control device is suggested to prevent accidents caused by rail potential increase.
- 91 - 3-28 A Study on the Real Time Measuring Technique of Stray Current by Using Return Current Ratio In the DC Railway System
First Author Abstract
Ho-Sung Jung In DC electric railways, while an electric rail car is [email protected] driving, a part of the working current returned to the 82-31-460-5116 substation through rails leaks into the ground. Such a stray current causes railways facilities and metal objects to corrode electrolytically. Therefore, change of stray current needs to be monitored constantly. Journal Info. But so far in domestic, the research on stray current measuring techniques and systems adaption are Transactions of Korea insufficient. To estimate stray current, this paper Institute of Electrical addresses a method of monitoring the return current Engineers that is returned into the negative pole of the Vol. 60 No. 4 substation in real time. 2011. 4
- 92 - 3-29 A Study on Fault Location Estimation Technique Using the distribution Ratio of Catenary Current in AC Feeding System
First Author Abstract
Ho-Sung Jung In AC feeding system, the fault location is [email protected] calculated by using ratio of current absorbed in the 82-31-460-5116 neutral point of AT(Automatic Transformer) or by measuring reactance. In this way, however, an estimation error can be happened due to the many reasons. In addition, for measuring currents in the JournalJournal of the Info.Korean neutral point of AT, other measuring devices and communication equipments are additionally required. Journal of the Korean In order to solve the disadvantages, this paper Society for Railway suggests a novel technique using the distribution Vol. 14 No. 5 ratio of catenary current. The proposed technique 2011. 10 uses existing protective relays and measures catenary current. With the measured data, we can calculate the distribution ratio of catenary current and determine fault location. Through the simulated results, we derived the correlation between current ratio and fault location. Using this technique, additional equipments and expenses can be reduced. Besides, fault location can be determined more correctly.
- 93 - 3-30 Bidirectional Alarm Equipment for Protection for Trackside Worker using Bone-anchored Speaker
First Author Abstract
Jong-Gyu Hwang Personnel maintaining or repairing the railway tracks [email protected] or signaling facilities around tracks may experience 82-31-460-5438 the sensory disorder when doing maintenance works at the trakside of railway for long time. In this case personnel maintaining at the trackside may collide with the train since they cannot recognize the approach of motor-car although it approaches to the JournalJournal of the Info.Korean vicinity of maintenance workplace because of the International Journal sensory block phenomenon occurred due to their of Safety long hours of continued monotonous maintenance Vol. 10 No. 1 work. In order to prevent such motor-car accidents 2011. 6 that may occur because railway track workers are unable to recognize the approaching train, the safety alarm equipment is developed to make the approaching motor-car send radio signals and bidirectional detection mechanism between approaching train and trackside personnel. It shows the possibility of utilization in various forms of safety equipment for workers only to the safety helmet to be worn by the maintenance
workers while using the configuration of transmitting/receiving sides. In the paper it is represented new alarm equipment, which is the bone-anchored speaker-based safety helmet to be worn by the maintenance workers.
- 94 - 4-01 Novel Air Filtration Device for Building Air Handling Unit
First Author Abstract
Soon-Bark Kwon Particulate matter (PM) is one of the major indoor air pollutants in the subway-underground stations in [email protected] Korea. Various kinds of PM removal methods such 82-31-460-5375 as a roll-filter, auto-washable air filter, demister, and electrostatic precipitator are applied in the air handling unit (AHU) of subway station. However, those systems are faced with operation and Journal Info. maintenance problems since the filter-regeneration achieved by air or water jet is often malfunctioned SCIE due to the high load of particulates. The filter material also needs periodic replacement. In this Aerosol and air quality research study, we designed a novel particle removal system with minimized maintenance requirement compared to Vol. 11 No. 5 above mentioned filter systems. The new system 2011. 10 named as panel-type cyclone system was suggested and the key part of the system was developed based on the axial-flow cyclone where the air flow pattern lies on the same axis with air stream through passing the AHU. The shape of axial-flow cyclone was optimized to remove 50% of 2.5 μm-sized particulate matters with minimal pressure drop by using the tool of computational fluid dynamics. We believe that the novel axial-flow cyclone system is cost-effective and efficient way of removing particulate matters in the size range of 1–0 μm in the AHU of subway station or buildings.
- 95 - 4-02 Instability Analysis in Curve Noise of Urban Railway Systems for Optimal Steering Bogie Development
First Author Abstract
Hyo-In Koh This paper is primarily aimed at investigating the excitation related factors of curve noise in urban metro [email protected] lines. This study is initiated within the scope of a 82-31-460-5207 project on the development of an active steering bogie, which has the purpose of reducing the wear and noise caused by curves. Noise and wheel profile monitoring tests were carried out four times in 2007–008. In order to identify the excitation conditions, the frequencies are Journal Info. investigated which are related to the unstable dynamic behaviors of the wheel. In addition, the curve SCIE negotiation performance of a metro train was analyzed Journal of Vibration & to investigate the time-domain characteristics of the Acoustics creepages and creep forces caused by the curved Vol. 133 No. 6 sections. The frequency region, where the flexible 2011. 12 dynamic behavior of a wheel is unstable and the occurrence time of the unstable dynamical behavior match well with the results of the noise measurements. The relationship between the noise generation related factors due to the lateral creepage in the contact region and the longitudinal creepage, the spin creepage could be also identified. As a new approach, the parameters related to the curve noise excitation caused by the dynamic instability of the wheel are predicted with consideration to the control concept of the active steering bogie, which is now in development. A calculation on the steering performance of an active steering bogie concept shows a promising reduction in and a stable dynamic condition of the lateral creep parameters of the inner front wheel.
- 96 - 4-03 Experimental Study on Particle Collection Efficiency of Axial-Flow Cyclone in Air Handling Unit
Corresponding Author Abstract
Soon-Bark Kwon A novel particle removal system for air handling [email protected] unit (AHU) of subway station was evaluated 82-31-460-5375 experimentally. The novel system was designed in order to minimize the maintenance cost by applying axial-flow cyclones. The system consists of multiple cyclone units and dust trap. Based on our previous numerical study, it was found to be effective for Journal Info. removal 1~10 mm sized dust particles. In this study, we manufactured the mock-up model and evaluated Journal of Koreaan the model experimentally. Liquid and solid test Society for Atmospheric particles were generated for evaluating collection Environment efficiency of the system and the pressure drop was Vol. 27 No. 3 monitored. The collection efficiency was varied from 2011. 6 41.2% to 85.9% with increasing the sizes of particle from 1 to 6.5 ㎛ by particle count ratio of inlet and outlet. The pressure drop was maintained constant
less than 20 mmH2O. In addition, the collection efficiency was estimated by total mass for solid test particles. It was found that the collection efficiency was 65.7% by particle mass ratio of inlet and outlet. It shows that present system can replace current pre-filters used in subway HVAC system for removing particulate matters with minimal operational cost.
- 97 - 4-04 Investigation of Airborne Microorganism in Cabin of the KTX
First Author Abstract
Soon-Bark Kwon The objective of this study is to assess a level of [email protected] microbial contamination in the KTX. Investigation 82-31-460-5375 sites in the KTX were cabin, gateway, toilet and passenger seat. It was found that the mean concentrations of airborne bacteria and fungi were 157 CFU/㎥ and 84 CFU/㎥, respectively, in all of the investigation sites of the KTX. They did not Journal Info. exceed the domestic standard (800 CFU/㎥) for airborne bacteria and the guideline (150 CFU/㎥) for Journal of Korean airborne fungi recommended by WHO. Mean levels Society for Indoor Environment of bacteria and fungi distributed in passenger seat were 2.6× cfu/㎠ and 3.7× , respectively. The Vol. 8 No. 1 predominant genera identified in the KTX were 2011. 3 Bacillus, Corynebacterium, Staphylococcus and Micrococcus for bacteria and Aspergillus, Cladosporium and Penicillium for fungi, respectively. Based on identification result, the profiles of airborne bacteria and fungi in the KTX was wholly similar to those of bacteria and fungi distributed in the passenger seat.
- 98 - 4-05 Development of Air Cleaning Roll-Filter for Improving IAQ in Subway
First Author Abstract
Soon-Bark Kwon In a modern society, various type of transportation [email protected] modes are utilized, among them the subway system is the one of the main transportation mode which 82-31-460-5375 more than 7.21 million people ride a day in Seoul. Due to the increased interests on the indoor air quality (IAQ) of underground facilities, public concerns on IAQ of subway system are increasing also. Platform screen door (PSD) recently installed at JournalJournal of the Info.Korean the whole stations of Seoul subway and tunnel washing-out appeared to be effective in reducing Journal of the Korean particulate matters in the platform and tunnel. Society for Railway However there has not been any attempt to improve IAQ of subway cabin inside. Most technologies for Vol. 14 No. 4 removing airborne particulate matters are known to 2011. 8 be difficult to adopt on the subway cabin due to the problem of maintenance cost. Therefore, the object of this study is a practical development of cabin air cleaning system which can reduce the concentration of airborne particles and harmful gases at the same time. In this paper, we focused on the development of particle removing system utilizing a roll-filter for increasing operating time of air filter. The prototype of system was designed and manufactured based on the numerical prediction results. For rollfilter device, 5 candidate filter materials were tested in point of particle collection efficiency and pressure drop. It was found that the electrically charged filter material showed the highest performance among them.
- 99 - 4-06 Air Quality in the Subway Cabins of the Seoul Metropolitan Area and Analysis of Its Influencing Factors Using Multivariate Statistics
Corresponding Author Abstract
Duck-Shin Park In this study, we have observed PM-10 and CO₂ [email protected] concentration in the subway cabins and analyzed the 82-31-460-5367 factors affecting air quality using a multivariate statistical analysis. The measurements have been conducted at Seoul metro-politan subway lines. The results show that the mean concentration of the PM-10 and CO₂inside subway cabins is in the Journal Info. range of 62.6 to 108.0 ㎍/㎥ and 907 to 2,008 ppm, respectively. CO₂level in specific sections during Journal of Koreaan Society for Atmospheric the rush hours has exceeded air quality guidelines Environment for public transportation, which requires designated train ventilation controls. Correlation and regression Vol. 27 No. 2 analyses of influencing factors imply that CO₂level 2011. 4 is severely influenced by the number of passengers and PM-10 level is also correlated with the number of passengers. In particular, PM-10 level in the cabins indicates a positive correlation with outdoor PM-10 level. In addition, the PM concentration has been highly affected by the number of passengers and distance between stations.
- 100 - 4-07 A Study for Characteristics of PM10 in the Subway passenger cabins
Corresponding Author Abstract
Duck-Shin Park This study had the aim of characteristics of PM10 in
[email protected] subway cabins. PM10 was measured by times of day 82-31-460-5367 (rush and non rush hours) and seasons with real
time PM10 sampler on the subway cabins of line 7. Filter samples were collected for evaluation of their elemental composition as well as identification of
major sources of PM10 using a receptor model, PMF. Journal Info. PM10 concentration were the highest in the winter season both in the rush and non rush hours at 152.8 Journal of Koreaan Society for Atmospheric ㎍/㎥, 90.2 ㎍/㎥ respectively. The PM10 Environment concentrations in rush hour were 30 % higher compared to non rush hours. Based on the chemical Vol. 27 No. 5 information, the composition rare of inorganic 2011. 10 elements was 52.5 %, anions were 10.2 % and others were 37.3 %. Fe was the most abundant element and significantly correlated (p<0.01) with Mn (r=0.97), Ti (r=0.91), Cr (r=0.88), Ni (r=0.89) and Cu (r=0.88). Characterized PM10 sources by PMF in the cabin were soil and road dust related sources (27.2 %), railroad related sources (47.5 %), secondary nitrate sources (16.2 %) and a Cl-factor mixed with a secondary sulfate source (9.1 %).
- 101 - 4-08 A Study on the Combustion Characteristics and Greenhouse Gas Emissions from Rice Husks with Varied Heat Fluxes
Corresponding Author Abstract
Duck-Shin Park This paper analyzes the combustion characteristics [email protected] and greenhouse gas emissions from varied heat 82-31-460-5367 fluxes with rice husks. In general, rice husks burnt outdoors at a lower temperature range of 300-400 ℃, which cannot assure complete combustion, thus generating a large volume of toxic air pollutants. A heat flux of 40 kW/m2, with a cone calorimeter, is Journal Info. the equivalent to the 700 ℃ of an incinerator. The test result shows that the mass reduction rate of the Journal of sample at this or at a higher temperature condition Environmental Science was 99.5% or higher, meaning that the sample was and Engineering almost completely combusted. In this study using Vol. 5 No. 2 rice husks, the amount of carbon dioxide, which is a 2011. 2 greenhouse gas, discharged were 1.57-3.61 kg/kg. This is as high as 10 times, than produced in other studies. When the rice husks are burnt outdoors, they are not completely combusted as the combustion temperature remains low, and the rice husk residuals are continuously being combusted in a smoldering phase which creates a large volume of carbon dioxide and carbon monoxide. Therefore, it is recommended to burn rice husks at 700 ℃ or higher to minimize the carbon dioxide and carbon monoxide emissions.
- 102 - 4-09 Full-Scale Test of Smoke-Control Performance of a Subway Tunnel
First Author Abstract
Won-Hee Park Hot smoke test is done in a subway tunnel. Alcohol [email protected] trays of 1.0 MW and smoke generators are used for 82-31-460-5358 generating hot smoke. The fans equipped with the tunnel are successively run 9 min after smoke generation. It is verified how hot smoke is controlled by fans. Velocity and direction of flow, temperature Journal Info. and smoke density are measured and analyzed for smoke control performance of the tunnel with fans Journal of Korean and analyzed from the fire-safety-point of view. Institute of Fire Science & Engineering Velocity of smoke flow is obtained by using measured velocity and temperature at the ceiling of Vol. 25 No. 4 the tunnel. The time when smoke-control flow is 2011. 8 builded up is different for the different positions. Velocity distributions at various positions will be used for the boundaries and the comparison data in numerical simulations for evaluation on smoke-control facilities of subway tunnel.
- 103 - 4-10 The Evaluation of GHG Emissions in Railroad Construction Sector
First Author Abstract
Jae-Young Lee According to governmental policies for green growth, [email protected] the increase in the traffic volume of railroad is a 82-31-460-5388 representative method to reduce total greenhouse gas (GHG) emitted from transport. Comprehensive assessment for the GHG emission of railroad has been studied to compare the difference of transport JournalJournal of the Info.Korean modes just in the operating step excluded the construction step. The purpose of this study was to Journal of the Korean evaluate GHG emissions in railroad construction Society for Railway sector. The targets were some construction works for Vol. 14 No. 3 civil, track, building, and electric system in A line. 2011. 6 The GHG emission source of constructing railroad infrastructure was mainly the energy consumption of heavy equipments. As a result, the civil construction sector showed more than 96% of total GHG emissions and its specific GHG emission was 2.191 ton CO2e/m. Also, the specific GHG emissions of civil construction works were of the order: earthworks > tunnels > bridges > station. In future, it will be required to calculate the overall GHG emission of railroad through life cycle approaches including operation, maintenance and disposal step.
- 104 - 4-11 A Research on the Greenhouse Gas Emission Reduction of Railway Structure Construction Stage
First Author Abstract
Cheul-Kyu Lee Concrete was identified as the significant GHG [email protected] emission source resulting from a GHG emission 82-31-460-5372 analysis of railway infrastructure. An environmental assessment method (life cycle assessment; LCA) and low carbon railway infrastructure design strategy development method (ECODESISGN PILOT) were JournalJournal of the Info.Korean applied to develop low carbon railway infrastructure design strategies. The railway infrastructure was Journal of the Korean analyzed as a raw material intensive industry Society for Railway emitting large amount of greenhouse gas (GHG) at Vol. 14 No. 5 its construction stage. Therefore, in this study, it is 2011. 10 analyzed that current status of GHG emission at its construction stage, and a method reducing GHG emission of railway infrastructure is proposed. In this study, eco-concrete, concrete aging prevention agent and a low carbon railway route decision method based on a need of low carbon railway infrastructure construction technology application for green railway development were considered..
- 105 - 4-12 Analysis of Vortex Shedding Phenomena around Pantograph Panhead for Train Using Large Eddy Simulation
First Author Abstract
Yong-Jun Jang The turbulent flow and vortex shedding phenomena [email protected] around pantograph panhead of high speed train were 82-31-460-5355 investigated and compared with available experimental data and other simulations. The pantograph head was simplified to be a square-cross-section pillar and assumed to be no interference with other bodies. The Journal Info. Reynolds number (Re) was 22,000. The LES(large eddy simulation) of FDS code was applied to solve Journal of Computational the momentum equations and the Wener-Wengle wall Fluids Engineering model was employed to solve the near wall turbulent Vol. 16 No. 2 flow. Smagorinsky model( =0.2) was used as 2011. 6 SGS(subgrid scale) model. The total grid numbers were about 9 millions and the analyzed domain was divided into 12 multi blocks which were communicated with each other by MPI. The time-averaged mainstream flows were calculated and well compared with experimental data. The phased-averaged quantities had also a good agreement with experimental data. The near-wall turbulence should be carefully treated by wall function or direct resolution to get successful application of LES methods.
- 106 - 4-13 The Distribution Characteristics of Carbon Dioxide in Indoor School Spaces
First Author Abstract
Young-Min Cho There are many studies reporting the average carbon [email protected] dioxide levels in various indoor spaces. However, 82-31-460-5362 there have been a few studies showing how carbon dioxide concentration varied at many measurement points in one indoor space. In this study, the changes of indoor carbon dioxide concentration at Journal Info. classroom, library, and kindergarten were reported to find its carbon dioxide distribution change at various Journal of Koreaan locations and altitudes. The maximum carbon dioxide Society for Atmospheric concentration of the 3 sites were measured as 2,684, Environment 2,295, and 1,526 ppm, respectively. These values Vol. 27 No. 1 exceeded the guideline concentration of 1,000 ppm 2011. 2 for public places. The concentration of carbon dioxide was higher at upper area than lower area, and this is probably due to the rise of warm breathing air generated from students. In the upper area, the carbon dioxide concentration was higher at center area than four corners. However, in the lower area, the carbon dioxide concentration was higher at four corners than center area. Therefore, it could be concluded that the center of upper area is the best place for the installation of ventilation or carbon dioxide removal system.
- 107 - 4-14 Adsorption and Desorption Characteristics of Carbon Dioxide at Low Concentration on Zeolite 5A and 13X
First Author Abstract
Young-Min Cho A way to adsorptively remove indoor carbon dioxide [email protected] at relatively lower concentration under ambient 82-31-460-5362 temperature was studied. A small lab-scale carbon dioxide adsorption and desorption reactors were prepared, and 5A and 13X zeolites were packed in this reactors to investigate their adsorption and desorption characteristics. The inflow carbon dioxide Journal Info. concentration was controlled to 5,000 ppm, relatively higher concentration found in indoor spaces with air Journal of Koreaan quality problems, by diluting carbon dioxide with Society for Atmospheric nitrogen gas. The flow rate was varied as 1~5 L/min, Environment and the carbon dioxide concentration after this reactor Vol. 27 No. 2 was constantly monitored to examine the adsorption 2011. 4 characteristics. It was found that 5A adsorbed more carbon dioxide than 13X. A lab-scale carbon dioxide desorption reactor was also prepared to investigate the desorption characteristics of zeolites, which is essential for the regeneration of used zeolites. The desorption temperature was varied as 25~200°C, and the desorption pressure was varied as 0.1~1.0 bar. Carbon dioxide desorbed better at higher temperature, and lower pressure. 5A could be regenerated more than three times by thermal desorption at 180°C. It is required to modify zeolites for higher adsorption and better regeneration performances.
- 108 - 4-15 Study on the Removal of Carbon Dioxide in the Subway Cabin Using Zeolite Type Carbon Dioxide Adsorbent
First Author Abstract
Young-Min Cho High concentration of carbon dioxide at subway [email protected] cabin is one of the serious environmental concerns 82-31-460-5362 because carbon dioxide causes drowsiness, headache, and nervelessness of passengers. Ministry of Environment set a guideline for indoor carbon dioxide levels in train or subway in 2007. In this study, a carbon JournalJournal of the Info.Korean dioxide removal system for subway cabin was developed and tested using a test subway cabin. Journal of the Korean Various types of modified zeolites were used as the Society for Railway adsorbent of carbon dioxide. The tested zeolites were Vol. 14 No. 1 applied to the subway cabin, and showed high 2011. 2 potential to lower the indoor CO 2 level.
- 109 - 4-16 A Study on the Performance Test and Acoustic Design of Interference Type Noise Reduction Device for Railway Noise
First Author Abstract
Jun-Ho Cho Noise barrier is generally used with welding of joint [email protected] rail for railway noise reduction in our country. But 82-31-460-5366 the noise barrier for high speed railway has weak point in low frequencies about 315Hz band. In this study, For developing of Interference-type Noise Reduction Device(INRD), acoustic analysis were Journal Info. performed using commercial software. For verifying the improvement in the noise reduction, noise Journal of measurement before and after installing of INRD Environmental Impact Assessment were performed in Anechoic Chamber. From these Vol. 20 No. 6 acoustic analysis and noise measurement, it was 2011. 11 known that developed INRD has a good noise reduction performance and can be used efficiently with conventional noise barrier.
- 110 - 5-01 A Multi-Class Closed Queueing Maintenance Network Model with a Parts Inventory System
First Author Abstract
Chan-Woo Park The system we address is a maintenance network of repairable items where a set of bases is supported by [email protected] a centrally located repair depot and a consumable 82-31-460-5545 replacement parts inventory system. If an item fails, a replacement part must be obtained at the parts inventory system before the failed item enters the Journal Info. repair depot. The ordering policy for the parts is the(S,Q) inventory policy. An approximation method SCIE for this system is developed to obtain performance Computers & Operations measures such as steady-state probabilities of the Research number of items at each site and the expected Vol. 38 No. 11 backorders at the parts inventory system. The 2011. 11 proposed system is modelled as a multi-class closed queueing network with asynchronization station and analyzed using a product-form approximation method. Particularly, the product-form approximation method is adapted so that the computational effort on estimating the parameters of the equivalent multi-class network is minimized. In analyzing a sub-network, are cursive method is used to solve balance equations by exploiting the special structure of the Markov chain. Numerical tests show that the approximation method provides fairly good estimation of the performance measures of interests.
- 111 - 5-02 A Study on Setting Up National Railway Safety Target
First Author Abstract
Sang-log Kwak According to the national railway safety plan 1 [email protected] billion US$ have been invested in railway industry 82-31-460-5544 every year. As a result, railway accident rate has been reduce to half recent 6 years. Currently, Korea has 3 kinds of national railway safety target, which are accident fatalities, train accident rate, and Journal Info. passenger fatality per passenger kilometer. Increase of railway passengers and train operating companies Journal of the Korean force to set up new safety target. Current safety Society for Railway target cannot reflect train operator's safety activities Vol. 14 No. 3 because they include suicide and trespass related 2011. 6 accidents, which are hard to be controlled by the operators. In order to reflect to the national railway safety plan, new safety targets are proposed in this study.
- 112 - 5-03 A Study on Revising Train Departure Time for Reducing Electric Power Consumption
Corresponding Author Abstract
Kyung-Min Kim This paper considers the problem of revising train [email protected] departure time to reduce electric power consumption 82-31-460-5491 of mass rapid transit (MRT) railways. The motion of a train running between stations is divided into three phases: traction, coasting, and deceleration phases. The traction phase requires high electric power to JournalJournal of the Info.Korean operate MRT railways. In the coasting phase, the train moves stably by consuming little or no power. Journal of the Korean The deceleration phase is a braking mode and Society for Railway produces some electric power called regenerated Vol. 14 No. 2 brake power owing to inertia force for the train 2011. 4 generated in the traction and coasting phases. The regenerative energy can be used by other accelerating trains within a specific range from the train and thereby the power consumptions of train can be reduced. We developed a mixed integer programming model to solve the problem. To validate the suggested model, a computational experiment was conducted using real data from Korea Metropolitan Subway.
- 113 - 5-04 Track Assignment and Load Planning Problems in Railway Container Terminals
First Author Abstract
Kyung-Min Kim This paper considers the problem of track assignment [email protected] and load planning (TALP) in railway container 82-31-460-5491 terminals. We formulated this problem as a multi-criteria mixed integer program that minimizes the delivery time of containers in terminals while simultaneously to minimize the make-span of Journal Info. terminal operations. We also applied our model to real-world data from the Uiwang Inner Container ICIC Express Letters Depot. Our experiments showed an improvement of Vol. 5 No. 9 approximately 19%, which means that our model can 2011. 9 improve the disposal capacity of containers without additional expansion of facilities.
- 114 - 5-05 Metaheuristics of the Rail Crane Scheduling Problem
Corresponding Author Abstract
Kyung-Min Kim This paper considers the rail crane scheduling [email protected] problem which is defined as determining the 82-31-460-5491 sequence of loading/unloading container on/from a freight train. The objective is to minimize the weighted sum of the range of order completion time and makespan. The range of order completion time Journal Info. implies the difference between the maximum of completion time and minimum of start time of each IE Interfaces customer order consisting of jobs. Makespan refers Vol. 24 No. 4 to the time when all the jobs are completed. In a 2011. 12 rail freight terminal, logistics firms as a customer wish to reduce the range of their order completion time. To develop a methodology for the crane scheduling, we formulate the problem as a mixed integer program and develop three metaheuristics, namely, genetic algorithm, simulated annealing, and tabu search. To validate the effectiveness of heuristic algorithms, computational experiments are done based on a set of real life data. Results of the experiments show that heuristic algorithms give good solutions for small-size and large-size problems in terms of solution quality and computation time.
- 115 - 5-06 Analysis of PRT Station Capacity Based on Micro Simulation
First Author Abstract
Baek-Hyun Kim The introduction of Personal Rapid Transit (PRT) [email protected] has been widely discussed in the Korean 82-31-460-5443 transportation research field. However, there is no robust criterion to derive the throughput of cars and passengers at PRT stations, which plays a primary role in determining the overall capacity of PRT Journal Info. systems. The present study provided a methodology to rigorously compute the capacity for simple-serial Transactions of Korea PRT stations with a single platform, considering Institute of Electrical three decisive factors, i.e., the demand level of Engineers incoming cars and outgoing passengers, the station Vol. 60 No. 12 structure, and the operation strategy. A micro-level 2011. 12 simulator was developed for the analysis of station capacity. And, by using this, station capacities were presented for various combinations of the decisive factors. In particular, the relationship between capacity and station structure was investigated in detail. Station structure is represented by the numbers of platform berths, input queue berths, and output queue berths. Moreover, both waive rate and waiting time, which represent the level of passenger service, were taken into account when the station throughput was computed.
- 116 - 5-07 Analysis on Recognition and Current Use of Pallets for Through Transit
First Author Abstract
Young-Joo Kim Nowadays many warehouses and logistics facilities [email protected] are designed based on pallet which is usually used 82-31-460-5476 as unit load. But it is hard to find reliable data about reasonable pallet size though pallet plays an important role in through transit. This paper aims to provide reliable data on current use and recognitions Journal Info. of pallets for through transit and analyze the survey results. The results show that less than 50% of Journal of DIMA companies do through transit and the others are Vol. 14 No. 2 reluctant to introduce it. Despite of merits of through 2011. 6 transit, various commodities and compatibility with customers becomes obstacles to achieve through transit. The analysis of the survey results shows that we can overcome the above problems by introducing additional pallets for through transit. Due to the difficulty of management, the number of additional pallets should be minimized.
- 117 - 5-08 Analysis of Operational Issues for ICT-based On-Board Train Control System
First Author Abstract
Young-Hoon Kim In order to minimize the maintenance cost at local [email protected] lines, Information & Communication Technology 82-31-460-5485 based on-board train control system is being developed. Unlike the central traffic control based fixed block system, this system use a moving block method and railway driver direct control switch and railway crossing. The purpose of this JournalJournal of the Info.Korean paper is to analyze the concerned main operational Journal of the Korean issues are as follows: the preparation of train Society for Railway operation, drivability, the role of driver and Vol. 14 No. 6 controller, block system and cost. We defined the 2011. 12 role of driver and driver’s input data for train service, and we designed the business process of driver using UML tool. We considered the aspect of drivability, DMI is needed to support the braking moment for the driver and driver training simulator. We designed the driver business process for control of switch and railway crossing. We analyzed the fixed block system and moving block system to confirm the difference with the existing operational method. The cost analysis structure is also needed for the operation cost comparison.
- 118 - 5-09 A Study on the Train Composition Requirements for Safety Operation of Urban-Transit
Corresponding Author Abstract
Jong-Bae Wang In order to assure the safety of train operation, a [email protected] safety function analysis corresponding hazardous 82-31-460-5541 events of railway accidents and a safety requirement review on operation & management of trains have been performed. The preconditions and train composition requirements such as safety principles JournalJournal of the Info.Korean and functions that should be essentially considered to enable the safety operation of Urban-Transit trains Journal of the Korean Society for Railway are clearly presented. On the basis of presented train Vol. 14 No. 1 composition requirements, a rational revise of Urban 2011. 2 Railway Operation Rule is proposed. It will be helpful in accident prevention and safety improvement for railway operation.
- 119 - 5-10 A Study on the DB Establishment and Traceable Management of the Urban Transit Standardization Project
First Author Abstract
Woo-Dong Lee The study and techniques of system engineering have [email protected] been applied to various fields including space-air, 82-31-460-5726 national defense division in advanced countries. Korea is currently in the early stages of introducing system engineering scheme in railway system and national defense division restrictedly. As theory and Journal Info. application of system engineering covers a wide scope, documents management and requirement analysis Journal of the Korean technology applied to establishment of standard and Society for Railway core unit development of the research target. The Vol. 14 No. 6 techniques which are historical management and trace 2011. 12 among standards for establishment of standard are introduced using SE tools and participating agencies shared the information by constructing of database from all documents which are generated from the project. Through the functional analysis of the requirements for the intelligent station monitoring system in basic design stage, established requirements are verified and will be made official announcement as standard of the intelligent station monitoring system.
- 120 -