• 제목/요약/키워드: Sources of variation

검색결과 609건 처리시간 0.029초

장소인식멀티센서스마트 환경을위한 데이터 퓨전 모델 (Locality Aware Multi-Sensor Data Fusion Model for Smart Environments)

  • 와카스 나와즈;무하머디 파힘;이승룡;이영구
    • 한국정보처리학회:학술대회논문집
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    • 한국정보처리학회 2011년도 춘계학술발표대회
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    • pp.78-80
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    • 2011
  • In the area of data fusion, dealing with heterogeneous data sources, numerous models have been proposed in last three decades to facilitate different application domains i.e. Department of Defense (DoD), monitoring of complex machinery, medical diagnosis and smart buildings. All of these models shared the theme of multiple levels processing to get more reliable and accurate information. In this paper, we consider five most widely acceptable fusion models (Intelligence Cycle, Joint Directors of Laboratories, Boyd control, Waterfall, Omnibus) applied to different areas for data fusion. When they are exposed to a real scenario, where large dataset from heterogeneous sources is utilize for object monitoring, then it may leads us to non-efficient and unreliable information for decision making. The proposed variation works better in terms of time and accuracy due to prior data diminution.

PSCAD/EMTDC를 이용한 마이크로그리드의 시뮬레이션 모델 개발 (Development of the Simulation Model of Micro-Grid using PSCAD/EMTDC)

  • 손광명;이계병;홍준희
    • 전기학회논문지
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    • 제56권3호
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    • pp.457-464
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    • 2007
  • Micro-Grid comprising Micro-Sources supplying several $kW{\sim}MW$ power to local customers is environmentally friendly and reliable. This paper deals with the development of simulation models of Micro-Grid on the PSCAD/EMTDC platform for analyzing various aspects of the interaction of the Micro-Grid. The developed switching level model adopts the space vector PWM. Both switching level and power frequency Micro-Source models are developed, which shows that power frequency modeling is sufficient for analyzing the phenomena of interest. Control characteristics of the Micro-Sources with the parameter and load power variation are analyzed for power quality enhancement. The simulation results show that the developed models are effective for studying Micro-Grid.

Transport and Loadings of Nutrients and Dissolved Major and Trace Elements in the Yeongsan River, Korea

  • Cha Hyun-Ju;Cho, Yeong-Gil
    • Journal of the korean society of oceanography
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    • 제37권2호
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    • pp.66-75
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    • 2002
  • Temporal variation of nutrients and dissolved major and trace elements have been studied in the Yeongsan River, Korea. There were significant temporal fluctuations in the concentrations of these elements depending upon the flow condition. $NH_4$, $PO_4$, Na, Mg, Ca, K, Mn, Cu, Ni, Zn, Co, As and U concentrations were inversely related to the flow; that is, they are the highest at low flow and the lowest at high flow. It indicates that these elements are derived from point sources such as rock weathering and/or human activities and then diluted by increasing flow. Meanwhile, Fe and Si concentrations varied proportionally to the flow indicating that they are derived from diffuse sources including reactions within soil. The concentration-flow relationships showed that hydrology of the river is the most important factor controlling the chemical composition of the Yeongsan riverwater, which was compatible of the results of R-mode factor analysis.

공동주택에서 음원특성에 따른 외부창호 차음성능 변화 (Variation of the Sound Insulation Performance of Window in the Apartment House depending on the Sound Source Characteristics)

  • 박현구;이옥균;한동화;송혁;김선우
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2000년도 춘계학술대회논문집
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    • pp.1735-1740
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    • 2000
  • The aim of this study is to analyze the sound insulation performance of windows depending on the sound source types and to propose the noise control method in the apartment house. The regions where apartment houses are constructed are varied in the dominant noise sources such as aircraft noise, railway noise and road traffic noise. For the experiment, nine noise sources including pink noise were selected and recorded, which was used in the experiment by reproducing. As a result of this study, the sound insulation performance of window was found that when the frequency contents of the noise were high level in all frequency bands the difference of sound insulation performance was negligible, but when the frequency contents were low level at particular frequency band the difference of sound insulation performance was shown very differently.

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질소원의 종류 및 초기 당농도가 곰팡이 Thraustochytrium aureum ATCC 34304의 성장 및 발효 특성에 미치는 영향

  • 김원호;허병기
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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    • pp.313-316
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    • 2000
  • The effects of initial sugar concentration and the various nitrogen sources on the fermentation characteristics of Thraustochytrium aureum were investigated. The sugar conversion ratios decrease with increase in the initial sugar concentration regardless of the kinds of nitrogen sources. The specific growth rate, the biomass yield, and the DHA yield also decreased but approached constant values higher than the concentration of 30g/L. The sugar conversion ratios and the specific growth rate showed the highest values in case of using the yeast extract as nitrogen source. It was difficult to conclude that the variation of nitrogen source had some effects on the biomass yield. However, the initial sugar concentration had a rather effects on the biomass yield for the sugar concentration of 40 g/L showed 0.27. The nitrogen source that showed the greatest yield of DHA was sodium glutamate.

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청소기용 Cyclone 소음원 및 저감방법 (Noise Reduction Method and Sources of Cyclone Sound for Vacuum Cleaner)

  • 이준화;홍승기;주재만;오상경;송화규;오장근
    • 한국소음진동공학회논문집
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    • 제15권4호
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    • pp.452-456
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    • 2005
  • Cyclone is widely adopted in the vacuum cleaner, because of the simple structure, the high dust collection efficiency and its transparency feature, which can be shown to the customer. At past times, cyclone performance was represented by collection efficiency, flow rate, pressure drop etc. At recent times the noise problem is getting important as cyclone comes into home-appliances. In this paper, pressure drop of cyclone and it's noise were measured at the variation of the cyclone structure and the main sources of cyclone peak noise was found by experimental and numerical analysis. In addition, the structure for peak noise reduction was suggested and it is beneficial both pressure drop and noise reduction.

청소기용 Cyclone 소음원 및 저감방법 (Noise Reduction Method and Sources of Cyclone for Vacuum Cleaner)

  • 이준화;홍승기;주재만;오상경;송화규;오장근
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2004년도 추계학술대회논문집
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    • pp.89-92
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    • 2004
  • Cyclone is widely apoted in the vacuum cleaner, because of it's simple structure, the dust collection efficiency is high and its transparency feaure which can be shown to the customer. At past times, cyclone performance is represented by collection efficiency, flow rate, pressure drop etc. At recent times the noise problem is getting important as cyclone comes into home-appliances. In this paper, cyclone's pressure drop and noise is measured at the variation of the cyclone structure and the main sources of cyclone peak noise is found by experiments and numerical analysis. In addition, the structure for peak noise reduction is suggested and it is beneficial both pressure drop and noise reduction.

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훈련 알고리듬을 이용한 변환격자코드에 의한 영상신호 압축 (Transform Trellis Image Coding Using a Training Algorithm)

  • 김동윤
    • 대한의용생체공학회:의공학회지
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    • 제15권1호
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    • pp.83-88
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    • 1994
  • The transform trellis code is an optimal source code as a block size and the constraint length of a shift register go to infinite for stationary Gaussian sources with the squared-error distortion measure. However to implement this code, we have to choose the finite block size and constraint length. Moreover real-world sources are inherently non stationary. To overcome these difficulties, we developed a training algorithm for the transform trellis code. The trained transform trellis code which uses the same rates to each block led to a variation in the resulting distortion from one block to another. To alleviate this non-uniformity in the encoded image, we constructed clusters from the variance of the training data and assigned different rates for each cluster.

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조명과 환경 변화에 강건한 화염 검출 시스템 (A Flame-Detection System Robust to Lighting and Environments)

  • 박장식;김현태;박수창;손경식
    • 한국화재소방학회논문지
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    • 제22권1호
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    • pp.68-75
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    • 2008
  • 본 논문은 화재를 조기에 검출하기 위하여 칼라 영상처리기법을 이용하여 주변 조명과 환경의 변화에 대하여 강건한 화염검출방법을 제안한다. 주변 조명과 화염의 RGB 색 분포 분석을 통하여 주변 조명과 화염을 구분할 수 있는 임계값을 설정하여 후보 영역을 검출한다. 화염이 발생 후 연속적으로 변화하기 때문에 화염 영역의 히스토그램 평균값의 차를 이용하여 화염 유사 영역을 제기한다. 검출된 영역이 화염임을 판단하기 위하여 영역 서술자인 밀집도를 계산하여 최종적으로 화염 여부를 판정한다. 컴퓨터 시뮬레이션을 통하여 제안한 방법이 화염을 보다 잘 검출하고 조명 등 주변 환경 변화에 강건함을 보인다.

PIXE 분석법에 의한 도로변 분진의 원소분석 (Elemental Analysis of Road Aerosols using by a PIXE Method)

  • 최금찬;임경택;조정구;김태형
    • 한국대기환경학회지
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    • 제12권5호
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    • pp.523-528
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    • 1996
  • Aerosol Particles were collected in a heaby traffic region in pusan. Samples were collected in two size fractions with a two-stage sampler during the day and the night. Elemental concentrations of these aerosol particles were determined by a PIXE(Proton Induced X-ray Emission) analysis method. The results suggest that the elements originating mainly from natural sources such as Si, Ca, Fe, Cl, and K are dominent in the coarse fraction, but the elements such as S, Pb, Br, and Zn are dominent in the fine fraction. Br/Pb ratio are evaluated in both coarse and fine size fraction, and which are mainly emitted automobile sources. The study further also discussed other Br/Pb ratio related works described elsewhere. Sulfur in the fine fraction was continuously increased during the sampling period without time variation.

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