• 제목/요약/키워드: Quality control algorithm

검색결과 919건 처리시간 0.03초

선형 평균스텝 양자화를 사용한 MPEG-2 비트율 제어 (A bit-rate control of MPEG-2 using linear average step quantization)

  • 이두열;이근영
    • 전자공학회논문지S
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    • 제34S권9호
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    • pp.84-90
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    • 1997
  • We proposed a new bit-rate control algorithm to improve MPEG-2 video software encoder. Bit-rate Control plays an improtant role in picture quality of MPEG-2 encoder. To achieve better encoding performance such as controlling picture quality and using bity properly, we proposed a MPEG-2 bit-rate control algorithm using linear average Step-Size. Using a benchmark Program, we compared our algorithm with MPEG-2 Test Model 5. Our proposed algorithm showed better Bit-Rate Control with respect to used bits, picture quality.

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단일편파 레이더자료 품질관리기술 특성 분석 (Analysis of Quality Control Technique Characteristics on Single Polarization Radar Data)

  • 박소라;김헌애;차주완;박종서;한혜영
    • 대기
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    • 제24권1호
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    • pp.77-87
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    • 2014
  • The radar reflectivity is significantly affected by ground clutter, beam blockage, anomalous propagation (AP), birds, insects, chaff, etc. The quality of radar reflectivity is very important in quantitative precipitation estimation. Therefore, Weather Radar Center (WRC) of Korea Meteorological Administration (KMA) employed two quality control algorithms: 1) Open Radar Product Generator (ORPG) and 2) fuzzy quality control algorithm to improve quality of radar reflectivity. In this study, an occurrence of AP echoes and the performance of both quality control algorithms are investigated. Consequently, AP echoes frequently occur during the spring and fall seasons. Moreover, while the ORPG QC algorithm has the merit of removing non-precipitation echoes, such as AP echoes, it also removes weak rain echoes and snow echoes. In contrast, the fuzzy QC algorithm has the advantage of preserving snow echoes and weak rain echoes, but it eliminates the partial area of the contaminated echo, including the AP echoes.

학교교실의 실내공기질 개선을 위한 환기장치 및 공기청정기의 연동제어 알고리즘 개발 및 적용 연구 (A study on Development and Application of Sequential Control Algorithm of Ventilation and Air Cleaning System for Improving Indoor Air Quality in School Classroom)

  • 박환출;이동현;이정재
    • 대한건축학회논문집:구조계
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    • 제36권5호
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    • pp.187-194
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    • 2020
  • This study presents the energy-saving sequential control algorithm to handle indoor CO2 and PM2.5 for the improvement of the air quality of school classrooms. To solve indoor air quality (IAQ) problems, air cleaning and ventilation systems are mainly used for school classrooms. Although air cleaning is able to collect PM2.5, it is difficult to remove harmful gas substances. The ventilation system is suitable to tackle CO and CO2, the volume ventilation, however, is relatively small. In this paper, to remove CO2 and PM2.5, the pollutant balance equation for improving indoor air quality is reviewed. The sequential control algorithm of the ventilation and air cleaning system with four levels of criteria is introduced for the effective removal of pollutants. The proposed sequential control algorithm confirms that indoor CO2 and PM2.5 can be properly controlled below the standard value. In addition, the sequential operation of air cleaning and ventilation systems has shown significant improvement in IAQ compared to the independent ventilation system operation. Particularly, such systems are efficient when outdoor PM2.5 is high.

Improved H.263+ Rate Control via Variable Frame Rate Adjustment and Hybrid I-frame Coding

  • 송환준
    • 한국통신학회논문지
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    • 제25권5A호
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    • pp.726-742
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    • 2000
  • A novel rte control algorithm consisting of two major components, i.e. a variable encoding frame rate method and a hybrid DCT/wavelet I-frame coding scheme, is proposed in this work for low bit rate video coding. Most existing rate control algorithms for low bit rate video focus on bit allocation at the macroblock level under a constant frame rate assumption. The proposed rate control algorithm is able to adjust the encoding frame rate at the expense of tolerable time-delay. Furthermore, an R-D optimized hybrid DCT/wavelet scheme is used for effective I-frame coding. The new rate-control algorithm attempts to achieve a good balance between spatial quality and temporal quality to enhance the overall human perceptual quality at low bit rates. It is demonstrated that the rate control algorithm achieves higher coding efficiency at low bit rates with a low additional computational cost. The variable frame rate method and hybrid I-frame coding scheme are compatible with the bi stream structure of H.263+.

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An Adaptive Rate Control Algorithm for RCBR Transmission of Streaming Video

  • Hwangjun Song
    • 한국통신학회논문지
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    • 제27권2A호
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    • pp.146-156
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    • 2002
  • This paper presents an adaptive H.263+ rate control algorithm for streaming video applications under the networks supporting bandwidth renegotiation, which can communicate with end-users to accommodate their time-varying bandwidth requests during the data transmission. That is, the requests of end-users can be supported adaptively according to the availability of the network resources, and thus the overall network utilization can be improved simultaneously. They are especially suitable for the transmission of non-stationary video traffics. The proposed rate control algorithm communicates with the network to renegotiate the required bandwidth fort the underlying video which are measured based on the motion change information, and choose their control strategies according to the renegotiation results. Unlike most conventional algorithms that control only the spatial quality by adjusting quantization parameters, the proposed algorithm treats both the spatial and temporal qualities at the same time to enhance human visual perceptual quality. Experimental results are provided to demonstrate that the proposed rate control algorithm can achieve superior performance to the conventional ones with low computational complexity under the networks supporting bandwidth renegotiation.

부유분진측정기(PM10) 관측 자료 실시간 품질관리 알고리즘 개발 및 평가 (Development and Assessment of Real-Time Quality Control Algorithm for PM10 Data Observed by Continuous Ambient Particulate Monitor)

  • 김선영;이희춘;류상범
    • 대기
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    • 제26권4호
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    • pp.541-551
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    • 2016
  • A real-time quality control algorithm for $PM_{10}$ concentration measured by Continuous Ambient Particulate Monitor (FH62C14, Thermo Fisher Scientific Inc.) has been developed. The quality control algorithm for $PM_{10}$ data consists of five main procedures. The first step is valid value check. The values should be within the acceptable range limit. Upper ($5,000{\mu}g\;m^{-3}$) and lower ($0{\mu}g\;m^{-3}$) values of instrument detectable limit have to be eliminated as being unrealistic. The second step is valid error check. Whenever unusual condition occurs, the instrument will save error code. Value having an error code is eliminated. The third step is persistence check. This step checks on a minimum required variability of data during a certain period. If the $PM_{10}$ data do not vary over the past 60 minutes by more than the specific limit ($0{\mu}g\;m^{-3}$) then the current 5-minute value fails the check. The fourth step is time continuity check, which is checked to eliminate gross outlier. The last step is spike check. The spikes in the time series are checked. The outlier detection is based on the double-difference time series, using the median. Flags indicating normal and abnormal are added to the raw data after quality control procedure. The quality control algorithm is applied to $PM_{10}$ data for Asian dust and non-Asian dust case at Seoul site and dataset for the period 2013~2014 at 26 sites in Korea.

차량 드로틀 보디 전장부품의 품질관리 성능시험 알고리즘 개발 (Development of Algorithm of Surge Test for Quality Control on Electrical Parts of Throttle Body in Automobiles)

  • 손재환;김태한
    • 한국산업융합학회 논문집
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    • 제9권1호
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    • pp.67-72
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    • 2006
  • This study is on the development of algorithm of surge test for quality control on electrical parts of throttle body in automobiles with internal combustion engine, not only to know its condition to be good or not, but also jugding its condition to be classified into six types. To know whether its condition to be good or not, comparing and analyzing between two waveforms generated from master and test coil of throttle body. If test net area is below 20% of master area, the condition of test coil is good. By analyzing test coil waveform to master coil waveform, the condition of test coil into winding badness, insulation badness, layer and corona discharge, short badness should known. Therefore quality control system on electrical parts of throttle body should be developed.

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150kVA급 전기품질 보상기기 제어 알고리즘 설계 (The Design of control algorithm for 150kVA power quality compensator)

  • 전진흥;김지원;전영환;김호용
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2001년도 하계학술대회 논문집 B
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    • pp.1070-1072
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    • 2001
  • In recent years, customers and power supplies are interested in power quality. Demands of customers are change from standard quality of distribution power system to various high quality of distribution power system. so, it is necessary to apply power quality compensator, in our project, we develop the power quality compensator of 150kVA which compensates power factor and voltage sag, interruption. it is very frequently occurred power qualify problems[1,2]. As a series and shunt compensator, power quality compensator consists of two inverters with common do link capacitor bank. It compensates the current quality in the shunt part and the voltage qualify in the series part. In this paper we present the design and control algorithm of power quality compensator. As a control algorithm is implemented by digital controller, we consider sample-and-hold of signals. In this simulation, we use EMTDC/PSCAD V3.0 software which can simulate instantaneous voltage and current.

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3상 직병렬보상형 전력품질 보상장치(UPQC)의 제어 알고리즘 설계 (The Design of Control Algorithm for Unified Power Quality Compensator)

  • 전진흥;김태진;류흥제;김황수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2004년도 하계학술대회 논문집 A
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    • pp.351-353
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    • 2004
  • In recent years, customers and power supplies are interested in power quality. Demands of customers are change from standard quality of distribution power system to various high quality of distribution power system. so, it is necessary to apply power quality compensator. in our project, we develop the UPQC(Unfied Power Quality Compensator of 45kVA which compensates power factor and voltage sag, interruption. it is very frequently occurred power quality $problems^{[1-3]}$ As a series and shunt compensator, UPQC consists of two inverters with common do link capacitor bank. It compensates the current quality in the shunt part and the voltage quality in the series part. In this paper, we present the design and control algorithm for 4SkVA UPQC system. As a control algorithm is implemented by digital controller, we consider sample-and-hold of signals. In this simulation, we use EMTDC/PSCAD V3.0 software which can simulate instantaneous voltage and current.

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ARR-TSE 기반의 정지 표적 정밀 크기 추정기법 연구 (A Study on the Static Target Accurate Size Estimation Algorithm with ARR-TSE)

  • 정윤식;김진환;김장은
    • 제어로봇시스템학회논문지
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    • 제21권9호
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    • pp.843-848
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    • 2015
  • In this paper, The ARR-TSE (Automatic Range Restore - Triangulation based target Size Estimator) algorithm is presented for IIR (Imaging Infrared) seeker. The target size is important information for the IIR target tracking. The TSE (Triangulation based target Size Estimator) algorithm has suitable performance to estimate target size for static IIR target. but, the performance of the algorithm can be decreased by noise. In order to decrease influence of noise, we propose the ARR-TSE algorithm. The performance of proposed method is tested at target intercept scenario. The simulation results show that the proposed algorithm has the accurate target size estimating performance.