Pulse Amplitude Modulation (PAM), Quadrature Amplitude Modulation (QAM)
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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. -
3 Characterization of Communication Signals and Systems
63 3 Characterization of Communication Signals and Systems 3.1 Representation of Bandpass Signals and Systems Narrowband communication signals are often transmitted using some type of carrier modulation. The resulting transmit signal s(t) has passband character, i.e., the bandwidth B of its spectrum S(f) = s(t) is much smaller F{ } than the carrier frequency fc. S(f) B f f f − c c We are interested in a representation for s(t) that is independent of the carrier frequency fc. This will lead us to the so–called equiv- alent (complex) baseband representation of signals and systems. Schober: Signal Detection and Estimation 64 3.1.1 Equivalent Complex Baseband Representation of Band- pass Signals Given: Real–valued bandpass signal s(t) with spectrum S(f) = s(t) F{ } Analytic Signal s+(t) In our quest to find the equivalent baseband representation of s(t), we first suppress all negative frequencies in S(f), since S(f) = S( f) is valid. − The spectrum S+(f) of the resulting so–called analytic signal s+(t) is defined as S (f) = s (t) =2 u(f)S(f), + F{ + } where u(f) is the unit step function 0, f < 0 u(f) = 1/2, f =0 . 1, f > 0 u(f) 1 1/2 f Schober: Signal Detection and Estimation 65 The analytic signal can be expressed as 1 s+(t) = − S+(f) F 1{ } = − 2 u(f)S(f) F 1{ } 1 = − 2 u(f) − S(f) F { } ∗ F { } 1 The inverse Fourier transform of − 2 u(f) is given by F { } 1 j − 2 u(f) = δ(t) + . -
Bit & Baud Rate
What’s The Difference Between Bit Rate And Baud Rate? Apr. 27, 2012 Lou Frenzel | Electronic Design Serial-data speed is usually stated in terms of bit rate. However, another oft- quoted measure of speed is baud rate. Though the two aren’t the same, similarities exist under some circumstances. This tutorial will make the difference clear. Table Of Contents Background Bit Rate Overhead Baud Rate Multilevel Modulation Why Multiple Bits Per Baud? Baud Rate Examples References Background Most data communications over networks occurs via serial-data transmission. Data bits transmit one at a time over some communications channel, such as a cable or a wireless path. Figure 1 typifies the digital-bit pattern from a computer or some other digital circuit. This data signal is often called the baseband signal. The data switches between two voltage levels, such as +3 V for a binary 1 and +0.2 V for a binary 0. Other binary levels are also used. In the non-return-to-zero (NRZ) format (Fig. 1, again), the signal never goes to zero as like that of return- to-zero (RZ) formatted signals. 1. Non-return to zero (NRZ) is the most common binary data format. Data rate is indicated in bits per second (bits/s). Bit Rate The speed of the data is expressed in bits per second (bits/s or bps). The data rate R is a function of the duration of the bit or bit time (TB) (Fig. 1, again): R = 1/TB Rate is also called channel capacity C. If the bit time is 10 ns, the data rate equals: R = 1/10 x 10–9 = 100 million bits/s This is usually expressed as 100 Mbits/s. -
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. -
2 the Wireless Channel
CHAPTER 2 The wireless channel A good understanding of the wireless channel, its key physical parameters and the modeling issues, lays the foundation for the rest of the book. This is the goal of this chapter. A defining characteristic of the mobile wireless channel is the variations of the channel strength over time and over frequency. The variations can be roughly divided into two types (Figure 2.1): • Large-scale fading, due to path loss of signal as a function of distance and shadowing by large objects such as buildings and hills. This occurs as the mobile moves through a distance of the order of the cell size, and is typically frequency independent. • Small-scale fading, due to the constructive and destructive interference of the multiple signal paths between the transmitter and receiver. This occurs at the spatialscaleoftheorderofthecarrierwavelength,andisfrequencydependent. We will talk about both types of fading in this chapter, but with more emphasis on the latter. Large-scale fading is more relevant to issues such as cell-site planning. Small-scale multipath fading is more relevant to the design of reliable and efficient communication systems – the focus of this book. We start with the physical modeling of the wireless channel in terms of elec- tromagnetic waves. We then derive an input/output linear time-varying model for the channel, and define some important physical parameters. Finally, we introduce a few statistical models of the channel variation over time and over frequency. 2.1 Physical modeling for wireless channels Wireless channels operate through electromagnetic radiation from the trans- mitter to the receiver. -
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. -
7.3.7 Video Cassette Recorders (VCR) 7.3.8 Video Disk Recorders
/7 7.3.5 Fiber-Optic Cables (FO) 7.3.6 Telephone Company Unes (TELCO) 7.3.7 Video Cassette Recorders (VCR) 7.3.8 Video Disk Recorders 7.4 Transmission Security 8. Consumer Equipment Issues 8.1 Complexity of Receivers 8.2 Receiver Input/Output Characteristics 8.2.1 RF Interface 8.2.2 Baseband Video Interface 8.2.3 Baseband Audio Interface 8.2.4 Interfacing with Ancillary Signals 8.2.5 Receiver Antenna Systems Requirements 8.3 Compatibility with Existing NTSC Consumer Equipment 8.3.1 RF Compatibility 8.3.2 Baseband Video Compatibility 8.3.3 Baseband Audio Compatibility 8.3.4 IDTV Receiver Compatibility 8.4 Allows Multi-Standard Display Devices 9. Other Considerations 9.1 Practicality of Near-Term Technological Implementation 9.2 Long-Term Viability/Rate of Obsolescence 9.3 Upgradability/Extendability 9.4 Studio/Plant Compatibility Section B: EXPLANATORY NOTES OF ATTRIBUTES/SYSTEMS MATRIX Items on the Attributes/System Matrix for which no explanatory note is provided were deemed to be self-explanatory. I. General Description (Proponent) section I shall be used by a system proponent to define the features of the system being proposed. The features shall be defined and organized under the headings ot the following subsections 1 through 4. section I. General Description (Proponent) shall consist of a description of the proponent system in narrative form, which covers all of the features and characteris tics of the system which the proponent wishe. to be included in the public record, and which will be used by various groups to analyze and understand the system proposed, and to compare with other propo.ed systems. -
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