• 제목/요약/키워드: distance estimation

검색결과 1,198건 처리시간 0.031초

독성물질 누출의 강도 산정 방법에 관한 비교 연구 (A Comparative Study on the Method of Consequence Estimation for Release of Toxicant Substances)

  • 김윤화;백종배;고재욱
    • 한국안전학회지
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    • 제9권1호
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    • pp.89-94
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    • 1994
  • Two methods, the numerical method of CPQRA and the manual method of IAEA, were used to estimate the effect distance from release and dispersion of toxic materials. The Gaussian plume model which has a weather stability class D with wind velocity of 5m/s was applied to calculate dispersion of toxic materials. Also, probit function were employed to evaluate the human fatality as a result of exposure to toxic gases. Furthermore, concentration of toxic materials corresponding to LC$_{50}$ for 30 min could be determined by setting Pr as 5.0 and solving the probit function. Calculations were conducted by employing chlorine and ammonia as toxic materials because they are not only most commonly used In chemical plants but also very harmful to humans. Calculated results by employing toxic materials indicated that the effect distance from the CPQRA method was between the minimum and maximum distance from the method proposed by IAEA.A.

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Real-Time Container Shape and Range Recognition for Implementation of Container Auto-Landing System

  • Wei, Li;Lee, Eung-Joo
    • 한국멀티미디어학회논문지
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    • 제12권6호
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    • pp.794-803
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    • 2009
  • In this paper, we will present a container auto-landing system, the system use the stereo camera to measure the container depth information. And the container region can be detected by using its hough line feature. In the line feature detection algorithm, we will detect the parallel lines and perpendicular lines which compose the rectangle region. Among all the candidate regions, we can select the region with the same aspect-ratio to the container. The region will be the detected container region. After having the object on both left and right images, we can estimate the distance from camera to object and container dimension. Then all the detect dimension information and depth inform will be applied to reconstruct the virtual environment of crane which will be introduce in this paper. Through the simulation result, we can know that, the container detection rate achieve to 97% with simple background. And the estimation algorithm can get a more accuracy result with a far distance than the near distance.

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Negative Exponential Disparity Based Robust Estimates of Ordered Means in Normal Models

  • Bhattacharya, Bhaskar;Sarkar, Sahadeb;Jeong, Dong-Bin
    • Communications for Statistical Applications and Methods
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    • 제7권2호
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    • pp.371-383
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    • 2000
  • Lindsay (1994) and Basu et al (1997) show that another density-based distance called the negative exponential disparity (NED) is an excellent competitor to the Hellinger distance (HD) in generating an asymptotically fully efficient and robust estimator. Bhattacharya and Basu (1996) consider estimation of the locations of several normal populations when an order relation between them is known to be true. They empirically show that the robust HD based weighted likelihood estimators compare favorably with the M-estimators based on Huber's $\psi$ function, the Gastworth estimator, and the trimmed mean estimator. In this paper we investigate the performance of the weighted likelihood estimator based on the NED as a robust alternative relative to that based on the HD. The NED based estimator is found to be quite competitive in the settings considered by Bhattacharya and Basu.

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풍력발전출력의 공간예측 향상을 위한 상관관계감소거리(CoDecDist) 모형 분석에 관한 연구 (A Study on the Analysis of Correlation Decay Distance(CoDecDist) Model for Enhancing Spatial Prediction Outputs of Spatially Distributed Wind Farms)

  • 허진
    • 조명전기설비학회논문지
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    • 제29권7호
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    • pp.80-86
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    • 2015
  • As wind farm outputs depend on natural wind resources that vary over space and time, spatial correlation analysis is needed to estimate power outputs of wind generation resources. As a result, geographic information such as latitude and longitude plays a key role to estimate power outputs of spatially distributed wind farms. In this paper, we introduce spatial correlation analysis to estimate the power outputs produced by wind farms that are geographically distributed. We present spatial correlation analysis of empirical power output data for the JEJU Island and ERCOT ISO (Texas) wind farms and propose the Correlation Decay Distance (CoDecDist) model based on geographic correlation analysis to enhance the estimation of wind power outputs.

Low-Complexity Design of Quantizers for Distributed Systems

  • Kim, Yoon Hak
    • Journal of information and communication convergence engineering
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    • 제16권3호
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    • pp.142-147
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    • 2018
  • We present a practical design algorithm for quantizers at nodes in distributed systems in which each local measurement is quantized without communication between nodes and transmitted to a fusion node that conducts estimation of the parameter of interest. The benefits of vector quantization (VQ) motivate us to incorporate the VQ strategy into our design and we propose a low-complexity design technique that seeks to assign vector codewords into sets such that each codeword in the sets should be closest to its associated local codeword. In doing so, we introduce new distance metrics to measure the distance between vector codewords and local ones and construct the sets of vector codewords at each node to minimize the average distance, resulting in an efficient and independent encoding of the vector codewords. Through extensive experiments, we show that the proposed algorithm can maintain comparable performance with a substantially reduced design complexity.

RGB-D 정보 및 거리변환을 이용한 보행자 검출 (Pedestrian Detection using RGB-D Information and Distance Transform)

  • 이호훈;이대종;전명근
    • 전기학회논문지P
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    • 제65권1호
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    • pp.66-71
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    • 2016
  • According to the development of depth sensing devices and depth estimation technology, depth information becomes more important for object detection in computer vision. In terms of recognition rate, pedestrian detection methods have been improved more accurately. However, the methods makes slower detection time. So, many researches have overcome this problem by using GPU. Here, we propose a real-time pedestrian detection algorithm that does not rely on GPU. First, the depth-weighted distance map is used for detecting expected human regions. Next, human detection is performed on the regions. The performance for the proposed approach is evaluated and compared with the previous methods. We show that proposed method can detect human about 7 times faster than conventional ones.

철도연변 지반 진동 Data Base 구축을 통한 지반진동예측 실험식 (Development of Empirical Equations for Estimating the Train-Induced Ground Vibration)

  • 황선근;고태훈;엄기영;오상덕
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2001년도 춘계학술대회논문집
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    • pp.1022-1027
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    • 2001
  • In this study, the train-induced vibration was measured at many locations at/around the actual service lines and the data base was constructed using the measurement results. The characteristics of train induced ground vibration was categorized and the empirical ground vibration estimating equations were developed. On the ground area (level grounds, embankments, cut sections), the vibration estimating equations were developed in terms of ground vibration level which was related with the distance from the source. Especially for the cut section areas, the vibration levels were expressed with the vibration receiving point expressed by the ratio of vertical distance to horizontal distance(V/H) from the source. As a result, when V/H is 0.96, the vibration estimating equation gives a minimum vibration level.

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A Study on the Minimum Safe Distance between Two Vessels in Confined Waters

  • Lee, Chun-Ki;Moon, Serng-Bae
    • 한국항해항만학회지
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    • 제38권6호
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    • pp.561-565
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    • 2014
  • This paper is mainly concerned with the interaction effects between two vessels and sidewall with a mound. Experimental study on hydrodynamic forces between ship and sidewall with a mound was already shown in the previous paper, measured by varying the distances between ship and sidewall. The ship maneuvering simulation was conducted to find out the minimum safe distance between vessels, which is needed to avoid sea accident in confined waters. From the inspection of this investigation, it indicates the following result. When and if one vessel passes the other vessel through the proximity of sidewall with a mound, the spacing between two vessels is needed for the velocity ratio of 1.2, compared to the case of 1.5. Also, for the case of ship-size estimation, the ship maneuvering motion is more affected by interaction effects for the overtaken small vessel, compared to the overtaking large vessel.

소실점과 움직임 객체간의 거리 추정 (Distance Estimation Between Vanishing Point and Moving Object)

  • 김동욱
    • 한국전자통신학회논문지
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    • 제6권5호
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    • pp.637-642
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    • 2011
  • 본 논문에서는 움직임 객체 검출 기법의 성능을 향상시키기 위하여 소실점과 움직임 객체간의 거리를 추정하는 기법을 제안한다. 이를 위하여 먼저, 주어진 입력 영상에 대하여 하프변환을 이용하여 소실점을 추정하고, 이를 바탕으로 소실점과 움직임 객체간의 거리를 추출한다. 얻어진 거리 정보는 움직임 객체 추출에 효과적으로 사용된다. 모의실험에서 제안된 기법에 대한 모의실험 결과를 제시하였으며, 객체단위의 거리추정을 객체 추정에 활용할 수 있음 확인할 수 있었다.

공항터미널 주기장 배정의 최적화에 대한 연구 (Optimizing Gate Assignment at Domestic Airport)

  • 이희남;김연명;이공섭;이창호
    • 대한안전경영과학회지
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    • 제4권4호
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    • pp.129-136
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    • 2002
  • Utilization rate for the restrictive gate and required time and walking distance to board are to be a measure for the gate management and passenger's convenience estimation. So, the main purpose of the gate management are maximization of utilization rate and increment of airport terminal user's convenience through the efficient gate management. This study intends to maximize the utilization rate on usable gates and minimize the passenger's working distance in terminal by concerning about layout, terminal configuration, local passenger of the airport and formulate the gate assignment problem with integer linear programming problem. Then we obtained solution using optimization software LINGO and analyzed that maximize the number of assignment flights and minimize the passenger's walking distance.