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Application of Noise Mapping in an Indian Opencast Mine for Effective Noise Management
12th ICBEN Congress on Noise as a Public Health Problem Application of noise mapping in an Indian opencast mine for effective noise management Veena Manwar1, Bibhuti Bhusan Mandal2, Asim Kumar Pal3 1 National Institute of Miners’ Health, Department of Occupational Hygiene, Nagpur, India (corresponding author) 2 National Institute of Miners’ Health, Department of Occupational Hygiene, Nagpur, India 3 Indian Institute of Technology-Indian School of Mines (IIT-ISM), Department of Environmental Science and Engineering, Dhanbad, India Corresponding author's e-mail address: [email protected] ABSTRACT So far as mining industry is concerned, noise pollution is not new. It is generated from operation of equipment and plants for excavation and transport of minerals which affects mine employees as well as population residing in nearby areas. Although in the Recommendations of Tenth Conference on Safety in Mines, noise mapping has been made mandatory in Indian mines still mining industry are not giving proper importance on producing noise maps of mines. Noise mapping is preferred for visualization and its propagation in the form of noise contours so that preventive measures are planned and implemented. The study was conducted in an opencast mine in Central India. Sound sources were identified and noise measurements were carried out according to national and international standards. Considering source locations along with noise levels and other meteorological, geographical factors as inputs, noise maps were generated by Predictor LimA software. Results were evaluated in the light of Central Pollution Control Board norms as to whether noise exposure in the residential and industrial area were within prescribed limits or not. -
Designline PROFILE 42
High Performance Displays FLAT TV SOLUTIONS DesignLine PROFILE 42 Plasma FlatTV 106cm / 42" WWW.CONRAC.DE HIGH PERFORMANCE DISPLAYS FLAT TV SOLUTIONS DesignLine PROFILE 42 (106cm / 42 Zoll Diagonale) Neu: Verarbeitet HD-Signale ! New: HD-Compliant ! Einerseits eine bestechend klare Linienführung. Andererseits Akzente durch die farblich gestalteten Profilleisten in edler Metallic-Lackierung. Das Heimkino-Erlebnis par Excellence. Impressively clear lines teamed with decorative aluminium strips in metallic finish provide coloured highlights. The ultimate home cinema experience. Für höchste Ansprüche: Die FlatTVs der DesignLine kombinieren Hightech mit einzigartiger Optik. Die komplette Elektronik sowie die hochwertigen Breitband-Stereolautsprecher wurden komplett ins Gehäuse integriert. Der im Lieferumfang enthaltene Design-Standfuß aus Glas lässt sich für die Wandmontage einfach und problemlos entfernen, so dass das Display noch platzsparender wie ein Bild an der Wand angebracht werden kann. Die extrem flachen Bildschirme bieten eine unübertroffene Bildbrillanz und -schärfe. Das lüfterlose Konzept basiert auf dem neuesten Stand der Technik: Ohne störende Nebengeräusche hören Sie nur das, was Sie hören möchten. Einfaches Handling per Fernbedienung und mit übersichtlichem On-Screen-Menü. Die Kombination aus Flachdisplay-Technologie, einer High Performance Scaling Engine und einem zukunftsweisenden De-Interlacer* mit speziellen digitalen Algorithmen zur optimalen Darstellung bewegter Bilder bietet Ihnen ein unvergleichliches Fernseherlebnis. Zusätzlich vermittelt die Noise Reduction eine angenehme Bildruhe. For the most decerning tastes: DesignLine flat panel TVs combine advanced technology with outstanding appearance. All the electronics and the high-quality broadband stereo speakers have been fully integrated in the casing. The design glass stand included in the scope of supply can easily be removed for wall assembly, allowing the display to be mounted to the wall like a picture to save even more space. -
Loudspeaker FM and AM Distortion an 10
Loudspeaker FM and AM Distortion AN 10 Application Note to the KLIPPEL R&D SYSTEM The amplitude modulation of a high frequency tone f1 (voice tone) and a low frequency tone f2 (bass tone) is measured by using the 3D Distortion Measurement module (DIS) of the KLIPPEL R&D SYSTEM. The maximal variation of the envelope of the voice tone f1 is represented by the top and bottom value referred to the averaged envelope. The amplitude modulation distortion (AMD) is the ratio between the rms value of the variation referred to the averaged value and is comparable to the modulation distortion Ld2 and Ld3 of the IEC standard 60268 provided that the loudspeaker generates pure amplitude modulation of second- or third-order. The measurement of amplitude modulation distortion (AMD) allows assessment of the effects of Bl(x) and Le(x) nonlinearity and radiation distortion due to pure amplitude modulation without Doppler effect. CONTENTS: 1 Method of Measurement ............................................................................................................................... 2 2 Checklist for dominant modulation distortion ............................................................................................... 3 3 Using the 3D distortion measurement (DIS) .................................................................................................. 4 4 Setup parameters for DIS Module .................................................................................................................. 4 5 Example ......................................................................................................................................................... -
Sensory Unpleasantness of High-Frequency Sounds
Acoust. Sci. & Tech. 34, 1 (2013) #2013 The Acoustical Society of Japan PAPER Sensory unpleasantness of high-frequency sounds Kenji Kurakata1;Ã, Tazu Mizunami1 and Kazuma Matsushita2 1National Institute of Advanced Industrial Science and Technology (AIST), AIST Central 6, 1–1–1 Higashi, Tsukuba, 305–8566 Japan 2National Institute of Technology and Evaluation (NITE), 2–49–10, Nishihara, Shibuya-ku, Tokyo, 151–0066 Japan ( Received 5 March 2012, Accepted for publication 2 August 2012 ) Abstract: The sensory unpleasantness of high-frequency sounds of 1 kHz and higher was investigated in psychoacoustic experiments in which young listeners with normal hearing participated. Sensory unpleasantness was defined as a perceptual impression of sounds and was differentiated from annoyance, which implies a subjective relation to the sound source. Listeners evaluated the degree of unpleasantness of high-frequency pure tones and narrow-band noise (NBN) by the magnitude estimation method. Estimates were analyzed in terms of the relationship with sharpness and loudness. Results of analyses revealed that the sensory unpleasantness of pure tones was a different auditory impression from sharpness; the unpleasantness was more level dependent but less frequency dependent than sharpness. Furthermore, the unpleasantness increased at a higher rate than loudness did as the sound pressure level (SPL) became higher. Equal-unpleasantness-level contours, which define the combinations of SPL and frequency of tone having the same degree of unpleasantness, were drawn to display the frequency dependence of unpleasantness more clearly. Unpleasantness of NBN was weaker than that of pure tones, although those sounds were expected to have the same loudness as pure tones. -
47 CFR Ch. I (10–1–06 Edition) § 15.117
§ 15.117 47 CFR Ch. I (10–1–06 Edition) § 15.117 TV broadcast receivers. comprising five pushbuttons and a separate manual tuning knob is considered to provide (a) All TV broadcast receivers repeated access to six channels at discrete shipped in interstate commerce or im- tuning positions. A one-knob (VHF/UHF) ported into the United States, for sale tuning system providing repeated access to or resale to the public, shall comply 11 or more discrete tuning positions is also with the provisions of this section, ex- acceptable, provided each of the tuning posi- cept that paragraphs (f) and (g) of this tions is readily adjustable, without the use section shall not apply to the features of tools, to receive any UHF channel. of such sets that provide for reception (2) Tuning controls and channel read- of digital television signals. The ref- out. UHF tuning controls and channel erence in this section to TV broadcast readout on a given receiver shall be receivers also includes devices, such as comparable in size, location, accessi- TV interface devices and set-top de- bility and legibility to VHF controls vices that are intended to provide and readout on that receiver. audio-video signals to a video monitor, that incorporate the tuner portion of a NOTE: Differences between UHF and VHF TV broadcast receiver and that are channel readout that follow directly from the larger number of UHF television chan- equipped with an antenna or antenna nels available are acceptable if it is clear terminals that can be used for off-the- that a good faith effort to comply with the air reception of TV broadcast signals, provisions of this section has been made. -
Statistical Distortion: Consequences of Data Cleaning
Statistical Distortion: Consequences of Data Cleaning Tamraparni Dasu Ji Meng Loh AT&T Labs Research AT&T Labs Research 180 Park Avenue 180 Park Avenue Florham Park, NJ 07932 Florham Park, NJ 07932 [email protected] [email protected] ABSTRACT There is considerable research in the database community We introduce the notion of statistical distortion as an essen- on varied aspects of data quality, data repair and data clean- tial metric for measuring the effectiveness of data cleaning ing. Recent work includes the use of machine learning for strategies. We use this metric to propose a widely applica- guiding database repair [14]; inferring and imputing miss- ble yet scalable experimental framework for evaluating data ing values in databases [10] ; resolving inconsistencies using cleaning strategies along three dimensions: glitch improve- functional dependencies [6]; and for data fusion [8]. ment, statistical distortion and cost-related criteria. Exist- From an enterprise perspective, data and information qual- ing metrics focus on glitch improvement and cost, but not ity assessment has been an active area of research as well. on the statistical impact of data cleaning strategies. We The paper [12] describes subjective and objective measures illustrate our framework on real world data, with a compre- for assessing the quality of a corporation’s data. An overview hensive suite of experiments and analyses. of well known data quality techniques and their comparative uses and benefits is provided in [2]. A DIMACS/CICCADA 1 workshop on data quality metrics featured a mix of speak- 1. INTRODUCTION ers from database and statistics communities. It covered a Measuring effectiveness of data cleaning strategies is al- wide array of topics from schema mapping, graphs, detailed most as difficult as devising cleaning strategies. -
En 300 720 V2.1.0 (2015-12)
Draft ETSI EN 300 720 V2.1.0 (2015-12) HARMONISED EUROPEAN STANDARD Ultra-High Frequency (UHF) on-board vessels communications systems and equipment; Harmonised Standard covering the essential requirements of article 3.2 of the Directive 2014/53/EU 2 Draft ETSI EN 300 720 V2.1.0 (2015-12) Reference REN/ERM-TG26-136 Keywords Harmonised Standard, maritime, radio, UHF ETSI 650 Route des Lucioles F-06921 Sophia Antipolis Cedex - FRANCE Tel.: +33 4 92 94 42 00 Fax: +33 4 93 65 47 16 Siret N° 348 623 562 00017 - NAF 742 C Association à but non lucratif enregistrée à la Sous-Préfecture de Grasse (06) N° 7803/88 Important notice The present document can be downloaded from: http://www.etsi.org/standards-search The present document may be made available in electronic versions and/or in print. The content of any electronic and/or print versions of the present document shall not be modified without the prior written authorization of ETSI. In case of any existing or perceived difference in contents between such versions and/or in print, the only prevailing document is the print of the Portable Document Format (PDF) version kept on a specific network drive within ETSI Secretariat. Users of the present document should be aware that the document may be subject to revision or change of status. Information on the current status of this and other ETSI documents is available at http://portal.etsi.org/tb/status/status.asp If you find errors in the present document, please send your comment to one of the following services: https://portal.etsi.org/People/CommiteeSupportStaff.aspx Copyright Notification No part may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm except as authorized by written permission of ETSI. -
DTV Interference Rejection Thresholds Are Shown on the Plot As a Reference
Interference Rejection Thresholds of Consumer Digital Television Receivers Available in 2005 and 2006 March 30, 2007 Technical Research Branch Laboratory Division Office of Engineering and Technology Federal Communications Commission OET Report Prepared by: FCC/OET 07-TR-1003 Stephen R. Martin ACKNOWLEDGEMENTS The author gratefully acknowledges the following contributions to this work. Mark Hryszko of the Digital Television group of Advanced Micro Devices provided the “Muddy Waters” RF vector file (mathematically derived from an MPEG2 transport stream) that was used with the Wavetech WS2100 RF player to provide a “desired signal” for the final few tests performed for this report. John Gabrysch of the Commission’s Media Bureau set up and evaluated the performance of the Rohde and Schwarz SFU DTV signal generator and developed channel assignment files for the instrument. The work of Charles Rhodes on third-order intermodulation inspired the paired-signal tests in this project. Gary Sgrignoli of MSW provided a fast-track DTV education to prepare the author for the prequel to this project. The author thanks the following Commission employees for reviewing drafts of this document: Alan Stillwell, Rashmi Doshi, and William Hurst (Office of Engineering and Technology); Doug Miller, John Raymond, and Steve DeSena (Enforcement Bureau); Richard Engelman and Sankar Persaud (International Bureau). The author also acknowledges the support of wife, Dr. Bonnie Dorr, through many long hours spent completing this work. i TABLE OF CONTENTS EXECUTIVE SUMMARY -
Spatial Characteristics of Distortion Radiated from Antenna Arrays with Transceiver Nonlinearities Christopher Mollen,´ Ulf Gustavsson, Thomas Eriksson, Erik G
1 Spatial Characteristics of Distortion Radiated from Antenna Arrays with Transceiver Nonlinearities Christopher Mollen,´ Ulf Gustavsson, Thomas Eriksson, Erik G. Larsson Abstract—The distortion from massive MIMO (multiple-input– paper is to give a rigorous description of the distortion created multiple-output) base stations with nonlinear amplifiers is studied by nonlinear hardware in multi-antenna transmitters, and to and its radiation pattern is derived. The distortion is analyzed quantify to which degree the distortion combines coherently. both in-band and out-of-band. By using an orthogonal Her- mite representation of the amplified signal, the spatial cross- The contribution of this paper is to give a rigorous correlation matrix of the nonlinear distortion is obtained. It continuous-time system model of a multi-antenna transmitter shows that, if the input signal to the amplifiers has a dominant for both single-carrier and OFDM (orthogonal frequency- beam, the distortion is beamformed in the same way as that beam. division multiplexing) transmission that uses digital precoding When there are multiple beams without any one being dominant, to beamform to multiple users. Orthogonal polynomials are it is shown that the distortion is practically isotropic. The derived theory is useful to predict how the nonlinear distortion will used to partition the amplified transmit signal into a desired behave, to analyze the out-of-band radiation, to do reciprocity signal—the linearly amplified signal—and a distortion term calibration, and to schedule users in the frequency plane to that is uncorrelated from the desired signal in order to analyze minimize the effect of in-band distortion. -
WAVEFORM TESTING Victor Nicholson CTIC the Urban Institute
WAVEFORM TESTING Victor Nicholson CTIC The Urban Institute Washington, DC have resulted in many complaints by broadcasters, of excessive degradation of their local channels when carried by a cable system. This is especially true of local UHF signals Abstract where interference is often introduced at the Existing subjective and frequency domain head end by the mixing of harmonics of the local testing procedures are shown to have major oscillator from the converter with other UHF. weaknesses in ensuring the delivery of accep Distribution system testing has little value in table television pictures to cable subscribers. resolving these complaints. Recommended, instead, are waveform test techniques using VIT signals as generated by Waveform test procedures have had little the networks. Applications of measurement application in the past to the cable industry as procedures and performance objectives are it was expensive to introduce these test signals discussed for echoes, noise and chrominance I at the head end. In addition, they provided no luminance gain and delay. information as to the quality of incoming tele ·,rision signals. Equipment was necessary to demodulate each channel, insert these diagnostic signals and then remodulate them; all of which added degradation to the desired TV signal. Today, waveform test procedures are applicable to the cable industry as these diagnostic signals are already injected into the Waveform testing of television signals four major network transmissions; ABC, CBS, introduces a valuable concept to the performance NBC, and PBS. This eliminates the need for testing and maintenance of R. F. distribution a cable operator to own expensive equipment to systems; including cable, satellite and fiber introduce these signals. -
Chapter 6 Mixers
Chapter 6 Mixers 1 Sections to be covered • 6.1 General Considerations • 6.2 Passive Downconversion Mixers • 6.3 Active Downconversion Mixers 2 Chapter Outline General Passive Mixers Considerations Conversion Gain Port-to-Port Feedthrough Single-Balanced and Double-Balanced Mixers Passive and Active Mixers Active Mixers Conversion Gain 3 Recall: Generic TX & RX 4 General Considerations (I) Mixers perform frequency translation by multiplying two waveforms. Example: mixer using an ideal switch VLO turns the switch on and off, yielding VVIF RFor V IF 0 multiplication of the RF input by a square wave toggling between 0 and 1, even if VLO is a sinusoid. ⋅ 5 General Considerations (II) Mixers perform frequency translation by multiplying two waveforms (and possibly their harmonics). Example: mixer using an ideal switch ⋅ VRF The circuits mixes the RF input with all of the LO harmonics, producing “mixing spurs”. The LO port of this mixer is very nonlinear. The RF port must remain sufficiently linear to satisfy the compression and intermodulation requirements. 6 Performance Parameters: Port-to-Port Feedthrough feedthrough from the LO port to the RF and IF ports. gate-source capacitances gate-drain capacitances Owing to device capacitances, mixers suffer from unwanted coupling (feedthrough) from one port to another. Example of LO-RF Feedthrough in Mixer Consider the mixer shown below, where VLO = V1 cos ωLOt + V0 and CGS denotes the gate-source overlap capacitance of M1. Neglecting the on-resistance of M1 and assuming abrupt switching, determine the dc offset at the output for RS = 0 and RS > 0. Assume RL >> RS. The LO leakage to node X is expressed as Basic component of VLO (square wave) can be expressed as The dc component： 8 The output dc offset vanishes if RS = 0. -
Improved Television Systems: NTSC and Beyond
• Improved Television Systems: NTSC and Beyond By William F. Schreiber After a discussion ofthe limits to received image quality in NTSC and a excellent results. Demonstrations review of various proposals for improvement, it is concluded that the have been made showing good motion current system is capable ofsignificant increase in spatial and temporal rendition with very few frames per resolution. and that most of these improvements can be made in a second,2 elimination of interline flick er by up-conversion, 3 and improved compatible manner. Newly designed systems,for the sake ofmaximum separation of luminance and chromi utilization of channel capacity. should use many of the techniques nance by means of comb tilters. ~ proposedfor improving NTSC. such as high-rate cameras and displays, No doubt the most important ele but should use the component. rather than composite, technique for ment in creating interest in this sub color multiplexing. A preference is expressed for noncompatible new ject was the demonstration of the Jap systems, both for increased design flexibility and on the basis oflikely anese high-definition television consumer behaL'ior. Some sample systems are described that achieve system in 1981, a development that very high quality in the present 6-MHz channels, full "HDTV" at the took more than ten years.5 Orches CCIR rate of 216 Mbits/sec, or "better-than-35mm" at about 500 trated by NHK, with contributions Mbits/sec. Possibilities for even higher efficiency using motion compen from many Japanese companies, im sation are described. ages have been produced that are comparable to 35mm theater quality.