• 제목/요약/키워드: physically based model

검색결과 250건 처리시간 0.022초

적응형 VOD 시스템을 위한 비디오 메타 데이터 모델 (Video Meta-data model for Adaptive Video-on-Demand System)

  • 전근환;신예호
    • 한국컴퓨터산업교육학회:학술대회논문집
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    • 한국컴퓨터산업교육학회 2003년도 제4회 종합학술대회 논문집
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    • pp.127-133
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    • 2003
  • The data models which express all types of video information physically and logically. and the definition of spatiotemporal relationship of video data objects In This paper, we classifies meta-model for efficient management on spatiotemporal relationship between two objects in video image data, suggests meta-models based on Rambaugh's OMT technique, and expanded user model to apply the adaptive model, established from hyper-media or web agent to VOD. The proposed meta-model uses data's special physical feature: the effects of camera's and editing effects of shot, and 17 spatial relations on Allen's 13 temporal relations, topology and direction to include logical presentation of spatiotemporal relation for possible spatiotemporal reference and having unspecified applied mediocrity.

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모자이크기법을 이용한 지표유출모형의 조도계수 리샘플링 (Resampling for Roughness Coefficient of Surface Runoff Model Using Mosaic Scheme)

  • 박상식;강부식
    • 한국환경과학회지
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    • 제20권1호
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    • pp.93-106
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    • 2011
  • Physically-based resampling scheme for roughness coefficient of surface runoff considering the spatial landuse distribution was suggested for the purpose of effective operational application of recent grid-based distributed rainfall runoff model. Generally grid scale(mother scale) of hydrologic modeling can be greater than the scale (child scale) of original GIS thematic digital map when the objective basin is wide or topographically simple, so the modeler uses large grid scale. The resampled roughness coefficient was estimated and compared using 3 different schemes of Predominant, Composite and Mosaic approaches and total runoff volume and peak streamflow were computed through distributed rainfall-runoff model. For quantitative assessment of biases between computational simulation and observation, runoff responses for the roughness estimated using the 3 different schemes were evaluated using MAPE(Mean Areal Percentage Error), RMSE(Root-Mean Squared Error), and COE(Coefficient of Efficiency). As a result, in the case of 500m scale Mosaic resampling for the natural and urban basin, the distribution of surface runoff roughness coefficient shows biggest difference from that of original scale but surface runoff simulation shows smallest, especially in peakflow rather than total runoff volume.

자탈형 콤바인의 선별모델 (Cleaning Model of Head-feeding Combine)

  • 김상헌;강화석;제임스 엠 그레고리
    • Journal of Biosystems Engineering
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    • 제19권1호
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    • pp.22-32
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    • 1994
  • The combine harvester is considered as an important but complicated and costly machine. The appropriate size of combine has to be developed to use efficiently in Korea. But the combine is such a complicated machine that a complete design model to develop a new type is impossible without understanding the relationship between each factor. The combine capacity is generally limited by the cleaning shoe performance. So a design model for a cleaning shoe has to be developed first for the complete combine design. The objective of this research was to develop a cleaning model of head-feeding combine to predict grain separation from chaff and broken straw on a sieve. A developed physically based model can explain the situation which can happen during separation process. A test apparatus based on the field going machine was developed. The test materials were paddy rice and barley. The data obtained were analyzed by the hand and the video camera. The developed model was verified as an adequate model through the test with $R^2$ of 0.934 and 0.837. The model can be used to evaluate design and operation alternatives of combine and also applied to the automatic control of separation unit of combine with a loss monitering sensors.

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MOS소자 반전층의 전자이동도에 대한 해석적 모델 (An analytical model for inversion layer electron mobility in MOSFET)

  • 신형순
    • E2M - 전기 전자와 첨단 소재
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    • 제9권2호
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    • pp.174-179
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    • 1996
  • We present a new physically based analytical equation for electron effective mobility in MOS inversion layers. The new semi-empirical model is accounting expicitly for surface roughness scattering and screened Coulomb scattering in addition to phonon scattering. This model shows excellent agreement with experimentally measured effective mobility data from three different published sources for a wide range of effective transverse field, channel doping and temperature. By accounting for screened Coulomb scattering due to doping impurities in the channel, our model describes very well the roll-off of effective mobility in the low field (threshold) region for a wide range of channel doping level (Na=3.0*10$^{14}$ - 2.8*10$^{18}$ cm$^{-3}$ ).

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대청댐 예비 방류를 위한 홍수 예보 (Flood Forecasting for Pre-Release of Taech'ong Reservoir)

  • 이재형;심명필;전일권
    • 물과 미래
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    • 제26권2호
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    • pp.99-105
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    • 1993
  • 호우발생전의 기상상태, 유역의 저류상태 그리고 과거의 패턴을 반영한 실용성 있는 홍수 예보모형을 제안하였다. 호우 예보는 구름 물리학을 토대로한 지점 호우 예보 모형을, 유출예측은 저류함수모형을 채택하였다. 홍수 예보 모형의 입력 변수는 예보 발령 시점의 지상 기온, 지상 기압, 지상 이슬점 온도 그리고 유출점의 초기 유량이다. 홍수 예보 모형의 매개 상수는 과거의 홍수 사상이 갖는 최적 상수들의 산술평균값으로 하였다. 유출률은 홍수 초기 유량을 지표로 하여 예측될 수 있게 하였다.

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SWAT 모형을 이용한 경안천 유역의 유출 및 유사량 추정 (Application of SWAT model to Gyeongancheon watershed for estimating stream flows and sediment yields)

  • 김철겸;김현준
    • 한국농공학회:학술대회논문집
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    • 한국농공학회 2003년도 학술발표논문집
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    • pp.527-530
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    • 2003
  • In this study, physically based SWAT model was applied to estimate the daily stream flows and sediment yields in Gyeongancheon watershed. The calibration and validation of the model outputs have been performed with yearly and daily measured stream flows of the time period 1988-1991 and 2001. The application results showed a good agreement with the simulated and observed stream flows, and similar trend with simulated and observed sediment yields. Overall, SWAT is a reasonable watershed scale model on long-term simulations of stream flows and sediment yields for management purposes.

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디젤 엔진 저온 시동 시스템 최적화를 위한 엔진 시동 과정의 동적 모델링 및 시뮬레이션 (Dynamic Modelling and Simulation of Engine Starting Process for Optimization of Diesel Engine Cold Starting System)

  • 박정규;배근식;유천
    • 한국자동차공학회논문집
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    • 제8권1호
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    • pp.32-39
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    • 2000
  • To optimize the cold start process of a 4-stroke, 8 cylinder Diesel engine, a dynamic simulation model from cranking to idle speed is developed. Physically-based first order starter motor dynamics are used to model the performance of starting process which is very complex. These equations are solved using numerical schemes(Petzold-Gear BDF method) to describe the starting process of diesel engine and to study the effects of starting parameters. The validity of this model is examined by start test. This model can be served as a tool for computer aided control systems design to improve cold improve cold start performance.

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미국의 최신 건강중심 체육교육수업의 소개 - Sports, Play, Active Recreation for Kids(SPARK) 체육프로그램 개발배경 및 사례보고 - (Introduction to a Health-related Physical Education Curriculum Model in the United States : Sports, Play, and Active Recreation for Kids (SPARK))

  • 유수진
    • 한국학교ㆍ지역보건교육학회지
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    • 제12권3호
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    • pp.101-109
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    • 2011
  • The purpose of this article is to introduce the Sports, Play, and Active Recreation for Kids (SPARK) physical education curriculum. SPARK is a model for health-related, research-based and evidence-based physical education programs in the United States. The outcome of school physical education can relate to public health, but there exists few evidence-based physical education programs reporting health-related variables. School physical education can provide more opportunities for children and adolescents to be physically active and to learn more about healthy lifestyles. However, physical education programs have been cut and eliminated due to lack of funding in the U.S. as in South Korea. Although facing these problems, SPARK programs have been implemented in over 50% of schools, after school programs and coordinated school health programs in the U.S. This article reviewed: (a) background information of the SPARK program, (b) examples of effective interventions, and (c) methods of dissemination to schools nationally in the U.S. The methods showed in SPARK may use as a model for researching, developing and implementing new physical education(PE) program and after school programs in Korea.

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빅데이터를 위한 H-RTGL 기반 단일 분류기 분산 처리 프레임워크 설계 (Design of Distributed Processing Framework Based on H-RTGL One-class Classifier for Big Data)

  • 김도균;최진영
    • 품질경영학회지
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    • 제48권4호
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    • pp.553-566
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    • 2020
  • Purpose: The purpose of this study was to design a framework for generating one-class classification algorithm based on Hyper-Rectangle(H-RTGL) in a distributed environment connected by network. Methods: At first, we devised one-class classifier based on H-RTGL which can be performed by distributed computing nodes considering model and data parallelism. Then, we also designed facilitating components for execution of distributed processing. In the end, we validate both effectiveness and efficiency of the classifier obtained from the proposed framework by a numerical experiment using data set obtained from UCI machine learning repository. Results: We designed distributed processing framework capable of one-class classification based on H-RTGL in distributed environment consisting of physically separated computing nodes. It includes components for implementation of model and data parallelism, which enables distributed generation of classifier. From a numerical experiment, we could observe that there was no significant change of classification performance assessed by statistical test and elapsed time was reduced due to application of distributed processing in dataset with considerable size. Conclusion: Based on such result, we can conclude that application of distributed processing for generating classifier can preserve classification performance and it can improve the efficiency of classification algorithms. In addition, we suggested an idea for future research directions of this paper as well as limitation of our work.

Grid-Based Localization of a Mobile Robot Using Sonar Sensors

  • Lim, Jong-Hwan;Kang, Chul-Ung
    • Journal of Mechanical Science and Technology
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    • 제16권3호
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    • pp.302-309
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    • 2002
  • This paper presents a technique for localization of a mobile robot using sonar sensors. Localization is the continual provision of knowledges of position that are deduced from its a priori position estimation. The environment of a robot is modeled by a two-dimensional grid map. We define a physically based sonar sensor model and employ an extended Kalman filter to estimate positions of the robot. Since the approach does not rely on an exact geometric model of an object, it is very simple and offers sufficient generality such that integration with concurrent mapping and localizing can be achieved without major modifications. The performance and simplicity of the approach are demonstrated with the results produced by sets of experiments using a mobile robot equipped with sonar sensors.