DEVELOPMENT OF SECURITY SYSTEM FOR

LNG TANK TRUCK

Hiromitsu Itou, Research and Development Institute, Saibu Gas Co., Ltd. Toshiaki Inaba, Production and Pipeline Planning Dept., Saibu Gas Co., Ltd.

1. COMPANY PROFILE Based in City, , We, Saibu Gas Co.,Ltd., supply city gas to 1,114,568 houses in 12 cities and 18 towns in three northern prefectures in Kyushu Island; Fukuoka, and Prefectures. (as of March 31st, 2002) As for materials of city gas, we have been shifting from petroleum/LPG to LNG for these years. In fact, we have completed the shift in Fukuoka City and Kitakyushu City Areas and in Kumamto Area, and now we are making the shift in Nagasaki Area. With this shift in the city gas materials, our Fukuoka LNG terminal (located in Fukuoka City, Fukuoka Pref.) started to accept LNG since October of 1993. Our Nagasaki Works newly built (Nagasaki City, Nagasaki Pref.) will start to accept LNG in 2003. LNG is imported from Malaysia by two vessels: “AMAN BINTULU” and “AMAN HAKATA” (capacity: 19,000m3 each). The following plants are responsible for production of our city gas; Fukuoka LNG terminal (located in Fukuoka City, Fukuoka Pref.), Kitakyushu Works (located in Kitakyushu City, Fukuoka Pref.), Kumamoto Works (located in Kumamoto City, Kumamoto Pref.), New Nagasaki Works (Nagasaki City, Nagasaki Pref.), Nagasaki Works (Nishi-Sonogi gun, Nagasaki Pref.) , Works (Sasebo City, Nagasaki Pref.) and Shimabara Works (Shimabara City, Nagasaki Pref.). Fukuoka LNG terminal and Kitakyushu Works are linked with each other by pipeline, while other works are independent.

2. LNG TRANSPORT BY TANK TRUCKS LNG accepted by our Fukuoka LNG terminal from Malaysia is evaporated at the Works, and is supplied as city gas. It is also distribute by our tank trucks to our Kumamoto Works, Sasebo Works, and neighboring city gas companies and shipyards (for fusing etc.). The annual LNG transportation amount is about 63,000 ton and the total number of distribution by the tank trucks comes to about 6,900 (FY 2003). These data show that the terminal is one of the biggest LNG distribution centers in . In order to maintain and enhance a high level of security on our tank trucks transporting a great deal of LNG, we Saibu Gas Co., Ltd., established a Tank Truck Control Room in the premises of Fukuoka LNG terminal. The Room aims to unify a range of operations related to security controls on the tank trucks and to reinforce the disaster preventing action systems which would be needed in case of occurrence of an accident or disaster. As one of the security controlling actions, we have developed a system for tank trucks. This new system aims to reduce the driver’s obligation to report an accident when it happens, and to improve security by automatically reporting an accident when a driver cannot report because of his injury. The new system enables the Room to receive prompt and accurate information on a tank truck’s travelling conditions (its location, its condition; travelling or stopping, etc.) and its abnormality such as (collision, sudden stop, liquid leakage, etc.) when it happens. Coupled with reporting an accident or abnormality through the conventional tool, that is mobile phone, the use of the new system is designed to improve the security control on tank trucks. The requirements of the new system are that the Tank Truck Management Room shall be able to receive and grasp the real-time travelling conditions of tank trucks and the occurrence of any abnormalities via the system and that the Room shall be able to provide prompt and accurate information on an accident or abnormality to related in-house sections and other municipal agencies (such as local police agency, fire-fighting agency, highway cooperation and others) when it occurs. Three companies have been committed to the development of the new system: Japan Radio Co.,Ltd., Saibugas Information System Co.,Ltd., and Saibu Gas Co.,Ltd.

Type of Tank Trucks Loading Capacity Amount of Tank Trucks 6.16 t 1 unit Single-Truck Vehicle 6.3 t 2 units 6.74 t 1 unit 9.8 t 6 units Semi-Trailer 10.5 t 10 units

Table 1. Specifications of LNG Tank Trucks

3. OUTLINE OF THE SYSTEM LNG Tank Truck Security System is composed of a base station system and a vehicle-loading system. Both systems are linked by mobile packet communication service system named “DoPa” provided by NTT-DOCOMO Co., Ltd. LNG Tank Truck Security System grasps the following information on the travelling conditions and abnormalities of a tank truck. Fig. 1 shows the outline of the system.

3.1 Travelling conditions of a tank truck (1) Travelling Location and Other Conditions GPS (Global Positioning System) loaded on a tank truck informs us where the tank truck is runnig. The informed location is displayed on a map in the base station by calling (pouring function) from the base station or from vehicle-loading system(contention function). The System also can display whether a tank truck is moving or stopping by judging the travelling speed which is calculated by informed location in a specified period.

(2) Travelling Status If a driver presses a function button on the display actuator installed on the dashboard, standard information ( such as Departure, Arrival, Arrival Prediction and Spare Information) is delivered to the base station system.

3.2 Reporting of abnormalities of a tank truck (1) Occurrence of High Gravity caused by Collision or Sudden Stop The tri-axial acceleration sensor installed on a tank truck monitors the forward and backward, side to side and vertical movement and vibration of the vehicle, and detects abnormal conditions caused by collision or sudden stop. If it happens, the system reports such conditions automatically to the base station system. (2) Abnormal Pressure of a Tank A temperature sensor installed on the automatic safety valve outlet detects a fall of temperature of the pipe which means the safety valve caused release the NG to reduce the in-tank pressure when it rise up abnormally, and the report of this abnormality is submitted to the base station system automatically.

(3) LNG Leakage LNG is loaded to or unloaded from the tank of a tank truck through the operation room of the rear section. A temperature sensor installed on the floor of the operation room detects a fall of floor temperature cause by LNG leakage from connection parts of the flanges or pipes, and automatically reports this abnormality to the base station system.

(4) Emergency Report If a driver presses the emergency button on the display actuator installed on the dashboard, the system automatically reports an abnormality to the base station system.

GPS Satellite

DoPa Communication Network of NTT DOCOMO

NTT Special Line

Vehicle-Loading System Base Station System

LNG tank truck

GPS Display Actuator

Tri-Axial Acceleration Sensor

Temperature Sensor Tank Truck Management Room Pressure Sensor

Fig. 1. Diagram of the System

4. VEHICLE-LOADING SYSTEM

4.1 Composition of vehicle-loading system Vehicle-loading system is composed of the following unites (see Table 2 and Fig.2) The system works to grasp how tank trucks are running and whether it’s conditions are normal or not.

Unit Names Q’ty

GPS Terminal Unit 1 unit GPS Antenna 1 unit Tri-Axial Acceleration Sensor 1 unit Temperature Sensor 2 units Temperature Sensor Converter 2 units Display Actuator 1 unit Sensor Box 1 unit Communication Terminal Unit(Mobile Ark) 1 unit Antenna for Mobile Ark 1 unit Power Source Box 1 unit Table 2. List of Vehicle-Loading Units

Antenna for Mobile Ark

Communication Terminal Unit Power Cable GPS Antenna (Mobile Ark) Power Source Box

RS-232C

Power Cable GPS Terminal Unit

Power Cable + RS-232C TTL

Power Cable Display Actuator Sensor Box

×2

Tri-Axial Acceleration Sensor Temperature Sensor Converter

×2

Temperature Sensor

Fig. 2. Diagram of Vehicle-Loading Units No. Items Specifications

1 Outer Dimensions 70 (W) x 70 (H) x 170(D) mm 2 Weight 1,000 g ( only the main body) 3 Power Source Voltage DC 24 V (10V～32V) 4 Consumption Current Max. 200 mA 100 m (2DRMS) 5 GPS Accuracy [in case that SA*1 is utilized] 6 Data Transmission Rate 9,600 bps 7 Serial Communication Rate Max. 38,400 bps 8 Radiation Noise Based on VCCI*2 9 Transmission Noise Based on VCCI 10 Temperature for storage －25 ℃ ～ ＋ 85 ℃ Flat Patch Antenna 11 GPS Antenna (Cable 5m with magnet) Table 3. Specifications of GPS Terminal Unit

*1 SA: Selective Availability Navigation Message Operation by Pentagon *2 VCCI: Voluntary Control Council for Interference by Information Technology Equipment (This organization aims to prevent radio wave interference voluntarily in cooperation with related industries.)

4.2 Characteristics of vehicle-loading system 4.2.1 Function blocks of vehicle-loading system Fig. 3 shows the function blocks of vehicle-loading system.

Base Station System

Vehicle-Loading System Mobile Ark

Control on communication with base station

Display GPS Communication Terminal Unit Display Actuator Input by button key

Setting of Normal Range Abnormal Data

Sensor Box Sensor Input by sensor

Fig. 3. Chart of Function Blocks of Vehicle-Loading System 4.2.2 Functions of GPS terminal units (1) Communication Control Function The System makes data communication if the mobile packet communication terminal unit (Mobile Ark) is connected with GPS terminal unit.

(2) Tank Truck’s Location Notification Function The System detects the current location of a tank truck. The current location of a tank truck is automatically displayed on the screen map in the base station when the travelling status is reported at every set time for contention, or the base station calls.

(3) Abnormality Report Notification Function When GPS terminal unit receives a report which the sensor box judges as abnormal, the System attaches the location information to the abnormality report and sends it the base station, and displays a warning on the display actuator.

(4) Emergency Report Transmission Function When the emergency button is pressed by driver, GPS terminal unit sends the emergency report with the location information to the base station immediately.

(5) Travelling Status Reporting Function When a button on the display actuator are pressed, the travelling status of a tank truck ( such as Departure, Arrival, Arrival Prediction and Spare Information) is reported to the base station.

(6) Specific Data Registration Function Writing of specific ID and/or network data can be performed at the serial port or data transmission.

4.2.3 Vehicle abnormality status monitoring sensor 4.2.3.1 Vehicle Status Monitoring by Tri-Axial Acceleration Sensor Tri-Axial (forward and backward, side to side and vertical directions) Acceleration Sensor monitors the vibration and movement of a tank truck. We have adopted Crossbow’s tri-axial sensor (made in USA) in this system. This type of sensor works by 5V power source and outputs by 0～5 V accelerating signal. As for the judgment values of abnormal status of a vehicle, it varied according to types of vehicles. Therefore, we researched for the judgment values of each type of vehicle while we made test runs of this system.

4.2.3.2 Installation Position of Tri-Axial Acceleration Sensor We installed the tri-axial acceleration sensor on the frame of a tank truck in order to catch the natural movement of the vehicle itself, not on the cabin unit in which the vehicle’s movement is affected by the air suspension. To be exact, we set the sensor in a waterproof and dustproof box made of protective steel and installed on the frame at the back of the front bumper of the vehicle, considering easiness to install and maintainability through discussion with the manufacturer of a vehicle. The sensor box is connected with using waterproof connector so that we can remove easily when necessary. Vertical

LNG Tank Truck Side to Side Forward and backward

Fig. 4. Movement of a Tank Truck

Sensor Box

( Acceleration Sensor is in the box)

Fig. 5. Installation Plan of Acceleration Sensor

4.2.3.3 Liquid Leakage and Abnormal Tank Pressure Monitoring by Temperature Sensor We installed temperature sensors on the exhaust pipe of safety valve and on the floor in the operation room in the rear side of the tank in order to monitor any movement of the safety valve and occurrence of liquid leakage. A pressure sensor monitors the tank pressure directly is also available as an optional item. As for the temperature sensors, we used sheath thermocouples (T-type) which works to convert the temperature signal “－50℃～350℃” into the voltage signal “1～5V” , and output the data into the sensor box. We also designed, made a relay box and installed it near the operation room to ease the replacement of the temperature sensor. The relay box is wired to the sensor box at the driver’s room with compensating lead for thermocouple. In case of semi-trailer type vehicle, we installed the relay connector at the connection part between the tractor unit and LNG tank unit that can be separated when necessary. In order to expand the contact area between thermocouple and the floor or pipe, we used temperature transferable sealant to fix it.

Installation Plan of Temp.

Sensor on Exhaust Pipe of Safety Valve

Installation Plan of Temp. Sensor on Floor of Operation Room in the Rear Tank.

Fig. 6 Installation Plan of Temp. Sensor

4.2.4 Sensor box 4.2.4.1 Function of Sensor Box The sensor box compares data from each sensor and the threshold values (standard value of judgment) to detect any abnormality. When the sensor box detects any abnormality, it sends the information to GPS vehicle-loading terminal unit and the unit reports the information to the center system along with the location information of the tank truck. The sensor box can treat data (shown in the Table 5).

No. Items Specifications

1 Outer Dimensions 143 (W) x 24.6(H) x 85.5 (D) mm 2 Weight 320 g 3 Power Source Voltage DC 24 V (allowable input ; 10～32V) 400 mA (12V) 4 Consumption Current 200 mA (24V) 5 Input Port Refer to Table 5 6 Operating Temperature －20 ℃ ～ ＋60 ℃ 7 Storage Temperature －30 ℃ ～ ＋75 ℃ 8 Output Voltage 5.0 V ± 5％（Less than Current 0.5A） 9 Control Connector 1 DSUB-15 pin 10 Control Connector 2 DSUB-15 pin 11 Fuse 3.15 A (to be installed on power cable) 12 Power Source Connector 3 pin 53108－0320 Table 4. Sensor Box Specifications

Inputting Type Port No. Specifications

Data Resolving Power : 8 bit (256 level) Sampling Frequency : 100 Hz Analogue 6 Input Voltage : 0 V ～ 5 V ( with Overvoltage Protection Function)

Digital 5 ON / OFF data

Point of Contact 5 The type of contact’s point can be change to by software

GPS terminal unit : TTL level RS-232C 2 Maintenance Port : RS-232C level Table 5. Input Port Specifications of Sensor Box

4.2.4.2 Judgment of Data from Sensors The sensor box receives data from each sensor connected with the port, and the software transacts the data in accordance with setting items stored in the inner unit in order to judge whether any abnormality occurs in the tank truck.

No. Setting Items Contents Setting Values

Upper Limit of Upper limit of normal range which a sensor box 0～255 1 Normal Range judges as abnormal. (255:No upper limitation is set)

Lower Limit of Lower limit of normal range which a sensor box 0～255 2 Normal Range judges as abnormal. (0: No lower limitation is set)

Judgment mode: Process method for computing values from a Any of immediate, average, sensor. The sensor box computes the values 3 Transaction Method integration from each sensor at the specified method and The mode can be set for each compares the values with the standard ones. port.

Cycle is determined for getting sensor data from 10msec ～ 655,350msec 4 Sampling Cycle each connection port. (10msec step)

Cycle is determined for transacting computation 10msec ～ 655,350msec 5 Transaction Cycle process specified in Transaction Method. (10msec step)

Names of the sensors (Sensor names are fixed 6 Sensor Names by the base station system)

Table 6. Sensor Input Port Setting Items

4.2.4.3 Judgment Mode for data from Sensors As for the computation process of data from sensors input values, the following three processing methods are provided. (a) Immediate Mode: In this mode, the sensor box compares each data. (1) The sensor box receives the data from each sensor every sampling period. (2) When the values go over the upper limit of normal range or go under the lower limit of normal range, abnormality warning is sent to the system. In the next sampling period, the sensor box repeats the (1)process and receives the input values from each sensor again. (b) Average Mode In this mode, the sensor box compares the average values of sampling times with the normal range. (1) The sensor box receives the data from each sensor every sampling period. It also adds the values obtained every time to calculate integrated values. (2) When in the transaction period, the sensor box divides the integrated values by the sample number in order to get the average values. (3) When the values go over the upper limit of normal range or go under the lower limit of normal range, abnormality warning is sent to the system.

(4) When the transaction is over, the integrated values and record of sample number are cleared. In the next sampling period, the sensor box repeats the from (1) to (3) processes and receives the data values from each sensor again. (c) Integration Mode In this mode, the sensor box compares the average values from the start of sampling (integrated values÷ sampling times) with the normal range. At every sampling period, the integrated values are reset. (1) This mode receives the input values from each sensor every sampling period. It also adds the values obtained every time to calculate integrated values. The mode divides the integrated values by the sampling times to obtain the average values. (2) When the values go over the upper limit of normal range or go under the lower limit of normal range, abnormality warning is sent to the system. (3) In the next sampling time, the mode receives the input values from each sensor as mentioned in (1) and divides the integrated values by the sampling times to obtain the average values. Comparison is made between the average values and standard ones as mentioned in (2). When the values go over the upper limit of normal range or go under the lower limit of normal range, abnormality warning is sent to the system. Thus, the integration calculates the average values every sampling time and compares it with the normal range. (4) When the transaction period comes, the integrated values and sampling times record are cleared. In the next sampling period, the sensor box repeats the (1)process and receives the input values from each sensor again to calculate the average values.

4.2.5. Performance confirmation function of sensor box 4.2.5.1 Self-Diagnosis Function at the Startup of Vehicle-Loading System When the power source of the vehicle-loading system is switched on, self-diagnosis function works to check the sensor box. When any abnormality is found in the sensor box, that is reported to the base station system. GPS terminal unit requests the sensor box to send the setting values to it. When the sensor box does not respond to the request, the system judges it as “abnormal”. When the response values from the sensor box are different from that of GPS terminal unit, the system judges it as “abnormal”. When abnormality is detected, abnormality flag is set at the initial communication, and this is notified to the base station system. When the base station system receives the notification that abnormal flag is set, it displays abnormality of the sensor box, turns on the patrolling light and gives voice notification of this abnormality.

4.2.5.2 Performance Confirmation Function from the Base Station System Performance of the sensor box and each sensor can be confirmed from the base station system. The base station system performs performance confirmation communication to registered tank trucks (to an individual tank truck or to all of them simultaneously). In case that a vehicle is in motion, the performance confirmation communication is performed when the vehicle is in communicable mode. When the vehicle-loading system receives the performance confirmation communication from the base station system, it requests the sensor box to send the values from each sensor to it. When this request fails, the vehicle-loading system sets the sensor box abnormality flag and responds to the base station system. The vehicle-loading system also sends the values of each sensor in motion in the sensor box to the base station system. The base station system displays the results of performance confirmation communication on the screen, and prints the result on forms. When there is any vehicle to which the communication fails, such a failure is displayed on the screen or printed on forms.

4.2.6 Installation of in-vehicle display actuator and reporting by each button When the in-vehicle display actuator is connected with the vehicle-loading system terminal unit, the following performances can be made; display of the status of the sensor box, emergency reporting by pressing the emergency button manually, and regular reporting (such as arrival, departure etc.) by operation of function keys. When the base station system receives information reported by function key, it displays the information along with vehicle number information, turns on patrolling light and gives voice notification.

No. Items Specifications

1 Outer Dimensions 180(W) x 60(H) x 40(D) mm 2 Weight 1,000 g (only the main body) 3 Power Source Voltage DC 13.8 V ±10% 4 Consumption Current Max. 500 mA (13.8V) 5 Serial Communication Rate 9,600 bps 6 LCD 168 × 65 dots Table 7. Display Actuator Specifications

4.2.7 Power Source Box The power source box supplies appropriate voltage power for each unit of the vehicle-loading system from the battery unit ( 24V) of the vehicle.

No. Items Specifications

1 Outer Dimensions 153.5(W) x 55.5(H) x 156.5(D) mm 2 Weight 1,000 g 3 Power Source Voltage DC 20 V ～ 32 V (allowable input) 4 Consumption Current 35 mA (when unloaded) 5 Output 1 Voltage 13.8 V ±0.5 V 6 Output 1 Current Max.5.5 A (DC24V, Temp.25℃) Output 1 Overvoltage 7 16.0 V ±0.5 V Protective Circuit 8 Output 2 Voltage 5.0 V ± 0.5 V 9 Output 2 Current Max. 0.5 A (DC24V, Temp.25℃) 10 Fuse 7.0 A Table 8. Power Source Box Specifications

5. BASE STATION SYSTEM 5.1 Composition of the system Table 9 shows the composition of the base station system.

No. Unit Names Q’ty Remarks

Base Station System PC: Control on the base station system PC with CD-ROM 1 1 set Implementation of Performance Monitoring CRT Monitor, key board, mouse, Software A set of connection cables 2 Hub 1 unit 3 Router 1 unit DoPa connection network 4 Printer 1 unit For forms output 5 Speaker 1 set 2 unit per set 6 Blinking light 1 unit 7 Uninterruptive Power Supply 1 unit 8 Magneto-Optical disk 1 unit Table 9. List of Components of the Base Station System

DoPa Communication Network of NTT DOCOMO LNG Tank Truck

NTT Special Line

Tank Truck Management Room Router

Hub

Blinking Light

PC Printer

Speakers Uninterruptive Power Source

Fig. 7. Diagram of Base Station System Units 5.2 Functions of base station system 5.2.1 Vehicle-Loading System and Communication Control Function Table 10 shows the communication control functions between the base station system and the vehicle-loading system.

Communication Types Communication Methods Data Obtained

Basic Data for Communication Registration of Basic Data ― for Communication Base Station Vehicle

DoPa Connector’s Phone Number, Confirmation Base Station/Vehicle-Loading IP Confirmation of Base Station Vehicle Address, Registered Information Default Router IP Address, Basic Data for Communication Subnet Mask, and Base Station System Port No. Request for vehicle’s location

Position, Altitude, Rate, and Calling Base Station Vehicle Direction Vehicle’s location data

Position, Altitude, Rate, and Contention Base Station Vehicle Direction Vehicle’s location data

Position, Altitude, Rate, and Direction,

Base Station Vehicle Values from each sensor Sensor’s Abnormality Location Data + Sensor Information (Acceleration Values, Temperature,

Pressure etc. )

Base Station Vehicle Position, Altitude, Rate, Direction, Emergency Report Vehicle’s location data and And Emergency Information

emergency information

Base Station Vehicle Position, Altitude, Rate, Direction Movement Status Report Vehicle’s location data and and Movement Status

movement status

Message

Message Base Station Vehicle Message (up to 10 full-size letters) Response to message

Table 10. List of Communication Control Functions 5.2.2. Collection Function of Vehicle’s Location Information 5.2.2.1 Calling (Pouring Function) The base station system requests the vehicle-loading system to send the information on the vehicle’s location. This calling has the following three modes: (1) Individual Calling : The system makes a calling per vehicle. (2) Selective Calling: The system makes a calling to all of the designated vehicles. (3) Automatic Calling: The system repeats calling to all of the designated vehicles.

5.2.2.2 Contention The vehicle-loading system sends the information on a vehicle’s location to the base station system. As for the receipt or cancellation of the receipt of vehicle’s location information and the receiving period, setting can be made on the base station system per vehicle. Table 11 shows the contention periods which can be set in the system.

No. Units Range of period

0 ----- No contention 1 Sec. 1～127 sec. 2 Min. 2～120 min. 3 3 hours ----- 4 6 hours ----- 5 12 hours ----- 6 24 hours ----- Table 11. contention periods

5.2.2.3 Trace Display Information on vehicle’s location obtained by calling or contention can be traced back up to 1,000 points and displayed.

5.2.3 Receiving Function of Sensor Abnormality and Emergency Alarm 5.2.3.1 Receiving Function of Sensor Abnormality When any abnormality is detected in the sensor data collected by the vehicle-loading system, information on the sensors (such as acceleration rate, temperature etc.) is sent to the base station system. When the base station system receives the information, it displays sensor information display window, turns on the patrolling light and gives a buzz. If a user clicks “PRINT” in the sensors’ abnormality dialogue, a location map around a vehicle with sensor abnormality and the alarmed information are printed.

5.2.3.2 Receiving Function of Emergency Alarming When the emergency button in the vehicle-loading system is pressed, emergency information is sent to the base station system. When the base station system receives the information, it displays emergency window, turns on the patrolling light and announces the emergency. When a user click “PRINT” in the emergency status dialogue, a location map around a vehicle with emergent problem is printed.

5.2.3.3 Setting Function of Sensor Abnormality & Emergency Alarm Reception Performance Settings of screen-popup, voice reporting, patrolling light, storing data in history database can be set by the following; every sensors in the sensor box, functions of the display actuator and when an emergency information is received. As for voice reporting function, it can be switched into voice file set in accordance with the content of the alarm.

5.2.3.4 Forms Output Function On receiving abnormality information from a vehicle, the base station system stores the information in the database inside the base station system. Such abnormality information can be arranged in a log form per vehicle (Abnormality Record per Vehicle) and per month (Abnormality Record per Month), displayed on the screen and printed.

5.2.3.5 Management of Normal Range for abnormality (Range Setting per Vehicle) Normal range for judgment of sensors’ abnormality can be set per vehicle. These normal range per vehicle are stored in the normal range database.

5.2.4 Management Function of Vehicle-Loading System 5.2.4.1 Confirmation on Communication Status of Vehicle-Loading System The communication status of the vehicle-loading system is displayed and printed. Displaying and printing information is managed by information transmitted from the vehicle-loading system and notification transmitted when the communication cannot be made.

5.2.4.2 Management Function of Vehicle Information Property information relating to each vehicle (such as ID, IP Address, Phone Number, Numbers on its license plate, Owner information) can be registered, deleted and modified.

5.2.4.3 Display Function of Vehicle Information This function works to display the property information of each vehicle and GPS information obtained by calling.

5.2.5 Processing Function of Operation Information 5.2.5.1 Display Function of Vehicle’s Movement When the system receives the movement information of a vehicle, the function compares the on-going operation status of the vehicle and its planned operation schedule, and displays its delay information in the form display. (Planned operation schedule must be input to the system in order to get delay information displayed)

5.2.5.2. Route Registration This function is to program the operation route of a vehicle with the destination defined as the place of departure and arrival.

5.2.5.3 Input of Operation Schedule This function is to make a daily operation schedule per vehicle by combining routes.

5.2.5.4 Operation Schedule Display This function is to make and display vehicle’s operation schedule in form of “1-month operation schedule of each driver, schedule per vehicle, 1-day or 1-week, or 1-month operation schedule of all vehicles.”

5.2.5.5 Operation Log Making This function works to make an operation log automatically by checking the on-going operation time of a vehicle, which is obtained when the movement of the vehicle is reported, against its operation schedule.

5.2.5.6 Detection of Delay in Vehicle’s Operation This function is to compute delay time by checking the on-going operation time of a vehicle, which is obtained when the movement of the vehicle is reported, against its operation schedule.

5.2.6 Map Display Function 5.2.6.1 Map Display This function displays the map data specified by Navigation System Researchers’ Association (Ver 2.1 and up). This function is able to display the map of everywhere in Japan. This System has employed “Road Map Data---Super National VersionⅡ produced by Zenrin Co.,Ltd.”

5.2.6.2 Enlargement and Reduction This function works to enlarge or reduce a map in eight size stages. Enlargement and reduction can be made with the center of a map fixed. The function displays a map of the whole Japan and an enlarged map of a designated area.

5.2.6.3 Scroll A user can read a map by moving a pointer on the map in eight directions (vertically, horizontally and diagonally) with scroll.

5.2.6.4 User Data Registration/Deletion A user can register the name and type of a destination by inputting it on the map with a mouse. The registered destination is displayed as a symbol.

6. COMMUNICATION INFRASTRUCTURE We have adopted “DoPa”, provided by NTT-DOCOMO. This is a mobile communication service based on packet communication method. ※ Under Packet Communication system, information is divided into packets. Each packet is attached with header of addressee and control information, and is transmitted to the designated address. Advantages of DoPa are high level of line use efficiency and low level in communication costs, since two or more users can conduct communication by sharing the common line.

6.1 Characteristics of DoPa 6.1.2 Communication Method and Operating Frequency * DoPa uses “PDC* Method, Frequency:800MHz Band” * DoPa is independent from voice channel and does not get affected by congestion of voice channel. ※ PDC: Personal Digital Cellular system 6.1.2 Advantages of DoPa (1) Wider Coverage Area * DoPa can be used in the same area as NTT-DOCOMO’s mobile phone covers. DoPa covers all of the operation routes of the existing LNG tank trucks. * Infrastructure of mobile wide range wireless LAN can be established. (2) Easy to Use * DoPa responds to “TCP/IP”, standard protocol of LAN and Internet. * Communication is kept online and so data communication can be performed immediately when necessary. (3) Economical * DoPa has specific charge system which responds to data amount. (4) High Level of Security * Confirmation of a terminal unit can be performed by checking IP Address against the phone number of a user. (5) Stable Network * Communication line is shared by users. This results in usual non-busy conditions of the line. * Communication line is not interrupted even when a vehicle is out of communication range of the system. As soon as the vehicle comes back to the range, communication restarts.

7. CONCLUSION

* We developed the system contributing to the safety operation of LNG tank trucks, and have successfully put the system in operation. * We are planning to upgrade the function of the system. For example, direct measurement of the pressure of the tank of a vehicle. * This system, which is designed for operation management of LNG tank trucks, can be applied to operation management of other kinds of vehicles just by changing sensors. * Automatic reporting function of the system is very effective especially for management of vehicles loading hazardous materials.

8. Others

* Saibugas Information System Co.,Ltd. is responsible for sales of this system.