• Title/Summary/Keyword: Noise standard

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A Study on Mixed Noise Removal using Standard Deviation and Noise Density (표준편차 및 잡음 밀도를 이용한 복합잡음 제거 알고리즘에 관한 연구)

  • Kwon, Se-Ik;Kim, Nam-Ho
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2017.10a
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    • pp.173-175
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    • 2017
  • With the rapid progress of the digital area has come the increase in demand for multi-media services. Imaging processing as a result is being hailed as a technological field that can offer smart and efficient methods for the processing and analysis of images. In general, noise exist in various types, depending on the cause and form. Some leading examples of noise are AWGN(additive white Gaussian noise), salt and pepper noise and complex noise. This study suggests an algorithm to remove complex noise by using the standard deviation and noise density of the partial mask in order to effectively remove complex noise in images.

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Evaluation on Acoustic Performance of the DICT's Acoustic Loboratory (대우건설기술연구소 음향실험동의 성능 평가)

  • 정갑철;이주원;윤창연;박칠림
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 1998.04a
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    • pp.735-740
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    • 1998
  • Acoustic performance of DICT's acoustic laboratory was evaluated. As a result, background noise and inverse squre law of an anechoic room were satisfied with ISO 3745 standard value. Also, reverberation time and standard deviation of sound pressure level distribution in reverberation rooms were within maximum error limit that was ruled on ISO 3741.

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Low Phase Noise CMOS VCO with Hybrid Inductor

  • Ryu, Seonghan
    • IEIE Transactions on Smart Processing and Computing
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    • v.4 no.3
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    • pp.158-162
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    • 2015
  • A low phase noise CMOS voltage controlled oscillator(VCO) for multi-band/multi-standard RF Transceivers is presented. For both wide tunability and low phase noise characteristics, Hybrid inductor which uses both bondwire inductor and planar spiral inductor in the same area, is proposed. This approach reduces inductance variation and presents high quality factor without custom-designed single-turn inductor occupying large area, which improves phase noise and tuning range characteristics without additional area loss. An LC VCO is designed in a 0.13um CMOS technology to demonstrate the hybrid inductor concept. The measured phase noise is -121dBc/Hz at 400KHz offset and -142dBc/Hz at 3MHz offset from a 900MHz carrier frequency after divider. The tuning range of about 28%(3.15 to 4.18GHz) is measured. The VCO consumes 7.5mA from 1.3V supply and meets the requirements for GSM/EDGE and WCDMA standard.

Development of Speed Increaser for High Speed Machine Pump which Considered the Noise/Vibration (소음/진동을 고려한 고속머신 펌프용 증속기 개발)

  • 이동환;박노길;김병옥;이형우
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.14 no.5
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    • pp.363-369
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    • 2004
  • Vibration/noise analysis as well as strength of gear teeth, roller bearing life. joural bearing design are considered in order to develop the high-speed machine centrifugal pump which had a speed increaser. A Campbell diagram, in which the excitation sources caused by the mass unbalance of the rotors and the transmitted errors of the gearing are considered. shows that. at the operating speed. there are not the critical speed. A high-speed machine centrifugal pump was made in order to evaluate developed speed increaser. Also, strict API standard were introduced for reliability evaluation of developed speed increaser, and performance evaluation were carried out. The result that evaluation items about bearing vibration, shaft vibration, noise, and lubrication temperature were selected, and were tested. a high-speed machine centrifugal pump were able to know what were satisfied with API standard all.

Inductive Switching Noise Suppression Technique for Mixed-Signal ICs Using Standard CMOS Digital Technology

  • Im, Hyungjin;Kim, Ki Hyuk
    • Journal of information and communication convergence engineering
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    • v.14 no.4
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    • pp.268-271
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    • 2016
  • An efficient inductive switching noise suppression technique for mixed-signal integrated circuits (ICs) using standard CMOS digital technology is proposed. The proposed design technique uses a parallel RC circuit, which provides a damping path for the switching noise. The proposed design technique is used for designing a mixed-signal circuit composed of a ring oscillator, a digital output buffer, and an analog noise sensor node for $0.13-{\mu}m$ CMOS digital IC technology. Simulation results show a 47% reduction in the on-chip inductive switching noise coupling from the noisy digital to the analog blocks in the same substrate without an additional propagation delay. The increased power consumption due to the damping resistor is only 67% of that of the conventional source damping technique. This design can be widely used for any kind of analog and high frequency digital mixed-signal circuits in CMOS technology

Development of a Sliding-Plug Entrance Door System for Urban Electric Transit Unit to Reduce Inside Noise Level (전동차 소음저감을 위한 슬라이딩플러그 출입문 개발)

  • 서승일;임영호;신동국
    • Journal of the Korean Society for Railway
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    • v.5 no.2
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    • pp.112-117
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    • 2002
  • Reduction of noise level in the cabin of urban transit unit is an important issue to enhance the comfortability of passengers. It is made clear that a cause of increased noise level in cabin is the imperfect airtightness of entrance doors. In this study, the sliding-plug door system is developed to reduce the noise level of cabins by securing the airtightness of entrance door. The sliding-plug door system is composed of air-driven engine, swing arms, guide rails, guide rollers and locking devices. It is economical owing to using the previous door engine system. It is also adequate for the platform system of our subway station. It was tested to prove the reliability of system and was applied to standard urban transit unit. The effectiveness of noise reduction in cabin resulting form the sliding-plug door system was confirmed by test results.

An Study KS Standardization for Acoustic noise measurement of the Wind Turbine (풍력발전시스템 소음평가의 KS 규격화에 관한 연구)

  • Son, C.Y.;Kim, J.H.;Oh, D.H.;Park, J.B.
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.11a
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    • pp.406-410
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    • 2005
  • The wind turbine, Europe and the United States are different with the standards process each other when the manufacturing company which in order to demand the standards process to a construction in the multi country with interested parties of the corresponding nation to, always the re-agreement is difficult. Korean wind turbine also detail there is not a standard, when it produces and establishes of wind turbine, the problem point occurs. It is like that investigation of international standards system it leads and when it prepares the Acoustic noise measurement of the Wind Turbine Systems of Korea, it prepares the base for industrial development wind turbine of Korea.

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A Study on Image Restoration Filter in Impulse Noise Environments (임펄스 잡음 환경에서 영상복원 필터에 관한 연구)

  • Xu, Long;Kim, Nam-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.2
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    • pp.475-481
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    • 2014
  • As the society develops to advanced digital information times, many studies are underway about digital video processing technology areas such as image restoration. There are typical methods to restore the image which have been damaged by the impulse noise like SM(standard median) filter and CWM(center weighted median) filter. These filters show excellent noise reduction capabilities in low noise density areas, but in high noise density areas, noise reduction capabilities are not sufficient. In this paper, in order to restore the degraded images in impulse(Salt & Pepper) noise environment, the image restoration filter algorithm was suggested which expands and subdivide the mask focusing on damaged pixels. And to demonstrate the superiority of the proposed algorithm used PSNR (peak signal to noise ratio) as the standard of judgement.

Modified Weighted Filter by Standard Deviation in S&P Noise Environments (S&P 잡음 환경에서 표준편차를 이용한 변형된 가중치 필터)

  • Baek, Ji-Hyeon;Kim, Nam-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.24 no.4
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    • pp.474-480
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    • 2020
  • With the advent of the Fourth Industrial Revolution, many new technologies are being utilized. In particular, video signals are used in various fields. However, when transmitting and receiving video signals, salt and pepper noise and additive white Gaussian noise (AWGN) occur for multiple reasons. Failure to remove such noise when performing image processing can cause problems. Generally, filters such as CWMF, MF, and AMF remove noise. However, these filters perform somewhat poorly in the high-density noise domain and cause smoothing, resulting in slightly lower retention of the edge components. In this paper, we propose an algorithm by effectively eliminating salt and pepper noise using a modified weight filter using standard deviation. In order to prove the noise reduction performance of the proposed algorithm, we compared it with the existing algorithm using PSNR and magnified images.

A study on the Phase Noise Performance of CATV Transmission System (CATV 전송시스템 위상잡음성능에 관한 연구)

  • Lee, Yong-Woo;Oh, Seung-Hyeub
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.10 no.4
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    • pp.199-204
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    • 2010
  • Recently, the transmission amount of information that each single person requires is growing by development of electron information communication technology. So in this paper we analysis the phase noise characteristics to obtain a most suitable of SNR performance request characteristic by BER on CATV transmission system that satisfy performance request DOCSIS 2.0 standard. Especially we get the parameter value of PLL that satisfy phase noise characteristic request standard using developed simulator. Presented method can be used to obtain a performance request standard connection performance request standard of high speed CATV transmission system in the future.