• 제목/요약/키워드: observation model

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확률적 표본화와 배경 차분을 이용한 비디오 객체 추적 (Visual Tracking Using Monte Carlo Sampling and Background Subtraction)

  • 김현철;백준기
    • 대한전자공학회논문지SP
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    • 제48권5호
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    • pp.16-22
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    • 2011
  • 본 논문에서는 배경 차분에 의해 객체를 검출하고 확률적으로 표본화된 입자 필터링(particle filtering)기법을 사용한 다중객체 추적 기법을 제안한다. 확률적으로 표본화된 입자들을 사용하여 다중 객체에 독립적으로 적용할 때 발생하는 계산 복잡도(computational complexity)를 감소시키는 동시에 안정적인 추적을 가능하게 하였다. 객체의 색상정보를 사용한 히스토그램 분포에 의한 관측 모델(observation model)을 구성하고 객체의 움직임 정보를 위해 동적 모델을 공식화하여 영상을 해석하였다. 전체적인 추적 시스템은 베이시언 최대 우도 기법(Bayesian maximum likelihood method)을 근간으로 하되, 입자 필터링을 객체 추적에 적용하여 실용적인 현실 객체 추적 상황에도 강건하게 대처할 수 있음을 실험을 통해서 증명하였다.

작물모형 평가를 위한 통계적 방법들에 대한 비교 (Comparison of Statistic Methods for Evaluating Crop Model Performance)

  • 김준환;이충근;손지영;최경진;윤영환
    • 한국농림기상학회지
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    • 제14권4호
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    • pp.269-276
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    • 2012
  • 작물모형 평가에 사용되거나 사용할 수 있는 9가지 지표를 소개하였으며 이들의 특징은 다음과 같다. efficiency of model (EF)와 index of agreement (d)은 dimension이 없고 관측수(n)에 의존적이지 않았으며, dimension에 대해서만 자유로운 것은 relative root mean square error (RRMSE), bias factor (Bf)와 accuracy factor (Af)이다. Root mean sqruar, mean error, mean absolute error들은 관측수와 dimension에 영향을 받기 때문에 판단 시 주의가 필요하다. 따라서 이들의 특징을 파악하여 목적에 맞게 모형의 성능을 파악하여야 한다.

Nonnegative variance component estimation for mixed-effects models

  • Choi, Jaesung
    • Communications for Statistical Applications and Methods
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    • 제27권5호
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    • pp.523-533
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    • 2020
  • This paper suggests three available methods for finding nonnegative estimates of variance components of the random effects in mixed models. The three proposed methods based on the concepts of projections are called projection method I, II, and III. Each method derives sums of squares uniquely based on its own method of projections. All the sums of squares in quadratic forms are calculated as the squared lengths of projections of an observation vector; therefore, there is discussion on the decomposition of the observation vector into the sum of orthogonal projections for establishing a projection model. The projection model in matrix form is constructed by ascertaining the orthogonal projections defined on vector subspaces. Nonnegative estimates are then obtained by the projection model where all the coefficient matrices of the effects in the model are orthogonal to each other. Each method provides its own system of linear equations in a different way for the estimation of variance components; however, the estimates are given as the same regardless of the methods, whichever is used. Hartley's synthesis is used as a method for finding the coefficients of variance components.

비가산성 잡음에서의 약한 화정적 신호의 검파방식에 관하여 (On a Detection Scheme for Weak Deterministic Signals in Non-Additive Noise)

  • Song, Iick-Ho
    • 대한전자공학회논문지
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    • 제25권9호
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    • pp.1019-1026
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    • 1988
  • A parametric detection scheme for determenistic signals is obtained in a generalized observation model which contains non-additive noise. The model employed in this paper includes several special cases such as those describing purely-additive noise, multiplicative noise, and signal dependent noise and allows the consideration of deterministic and random signals. Locally optimum detectors for known deterministic signals in the model are derived and analyzed for performance. It is shown that the locally optimum detectors are interesting generalizations of those for the purely-additive noise model. Performance of the locally optimum detectors designed for the generalized observation model is compared to that of other common detectors.

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중학생의 전류에 대한 학습전 개념과 관계 현상 관찰후의 설명 (Middle school students' conceptions related to electric current and their explanation after observation of related phenomena before school instruction)

  • 김영민;박윤희;박승재
    • 한국과학교육학회지
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    • 제10권1호
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    • pp.47-55
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    • 1990
  • The purposes of this study are to investigate Korean middle school students' conceptions related to electric current, and to analyze their changes in explanations about current after their observations of the related phenomena The subjects of the study were 20 students from one middle school in Seoul The conclusions of the studty are as follows: 1, Korean middle school students have various misconceptions such as current consumption model, sequential model, monopole model, non-various current model, the most students have sequential model' 2. When an evidence is introduced, some students do not perceive the phenomena as the teacher attempts. 3. When an evidence was introduced, after observation of the evidence some of the students who had misconceptions changed their explanatios, which were not always correct explanations, and the others did not change their expanations, which their observations were mostly incorrect.

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피지에 기초를 둔 HMM을 이용한 음성 인식 (Speech Recognition Using HMM Based on Fuzzy)

  • 안태옥;김순협
    • 전자공학회논문지B
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    • 제28B권12호
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    • pp.68-74
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    • 1991
  • This paper proposes a HMM model based on fuzzy, as a method on the speech recognition of speaker-independent. In this recognition method, multi-observation sequences which give proper probabilities by fuzzy rule according to order of short distance from VQ codebook are obtained. Thereafter, the HMM model using this multi-observation sequences is generated, and in case of recognition, a word that has the most highest probability is selected as a recognized word. The vocabularies for recognition experiment are 146 DDD are names, and the feature parameter is 10S0thT LPC cepstrum coefficients. Besides the speech recognition experiments of proposed model, for comparison with it, we perform the experiments by DP, MSVQ and general HMM under same condition and data. Through the experiment results, it is proved that HMM model using fuzzy proposed in this paper is superior to DP method, MSVQ and general HMM model in recognition rate and computational time.

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대단위발전소의 대기오염물질 확산에 관한 모델링 및 평가에 관한 연구 (Modeling and Evaluation on the Dispersion of Air Pollutants in the Large Scale Thermal Power Plant)

  • 전상기;이성철
    • 환경영향평가
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    • 제6권2호
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    • pp.81-92
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    • 1997
  • This paper presents the results from the comparison analysis and evaluation between the air pollutant dispersion modeling results and the observation data in the area within a 10 km radius from the Boryong thermal power plants. The observation data used in this study were the air pollutant concentrations which had been continuously measured from 8 locations around the Boryong power plants by TMS(tele-monitoring system) for 3 months from September to November, 1996. The short-term and long-term predictions were carried out using ISC3 model and LPDM(Lagrangian Panicle Dispersion Model). The results of ISC3 modeling in a short-term showed highly as 0.7 in a correlation coefficient, but in a long-term showed just 0.54. On the other hand, LPDM showed 0.78 in a correlation coefficient for a long-term, but in a short-term showed highly value than the observation concentrations.

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3차원 수치모델을 이용한 섬진강 하구역의 염수침입 특성 (Saltwater Intrusion Characteristics in Seomjin River Estuary using EFDC)

  • 강보식;박효봉;김종규
    • 수산해양교육연구
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    • 제27권6호
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    • pp.1842-1853
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    • 2015
  • The behavior characteristics of the saltwater intrusion in the Seomjin River Estuary by the inflow of fresh water were analysed by the field observation using CTD in the neap tide in January, June, and August 2013 as well as a numerical model, EFDC (Environmental Fluid Dynamics Code). As a result, Seomjin River Estuary is found that the saltwater intrusion is sensitive to the tide and tidal and freshwater flow. The results of field observation and numerical model were similar in the range of salt, but the results of salt wedge distribution were quite different. The observation of tide and tidal current as well as hydrographic surveying the Seomjin River Estuary will be jointly conducted for the accurate analysis.

Compressed Sensing-based Multiple-target Tracking Algorithm for Ad Hoc Camera Sensor Networks

  • Lu, Xu;Cheng, Lianglun;Liu, Jun;Chen, Rongjun
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제12권3호
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    • pp.1287-1300
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    • 2018
  • Target-tracking algorithm based on ad hoc camera sensor networks (ACSNs) utilizes the distributed observation capability of nodes to achieve accurate target tracking. A compressed sensing-based multiple-target tracking algorithm (CSMTTA) for ACSNs is proposed in this work based on the study of camera node observation projection model and compressed sensing model. The proposed algorithm includes reconfiguration of observed signals and evaluation of target locations. It reconfigures observed signals by solving the convex optimization of L1-norm least and forecasts node group to evaluate a target location by the motion features of the target. Simulation results show that CSMTTA can recover the subtracted observation information accurately under the condition of sparse sampling to a high target-tracking accuracy and accomplish the distributed tracking task of multiple mobile targets.

${\cdot}$粘塑性構成式을 使用한 粘性土地盤의 變形解析 (An Analysis on the Deformation of Clayey Foundation Using Elasto-Viscoplastic Model)

  • 이문수
    • 한국농공학회지
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    • 제34권2호
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    • pp.60-72
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    • 1992
  • This study aims at predicting the behavior of saturated soft clayey foundation subjected to earth structure loads such as tidal dike, embankment etc. by using Biot's consolidation equation coupled with elasto-viscoplastic constitutive model. To validate the computer program developed b author, a case study was performed for the site of Kwang-yang steel works improved by sand drain, where since the beginning of the works, field measurements(settlement, lateral displacement and excess pore water pressure) had been accurately achieved. Comparisons between numerical results and observation values were carried out. The main results obtained are summarized as follows : 1. Settlement and lateral displacement between numerical and observation values show satisfactory accordance. 2. As for the exess pre water pressure, numerical results appear to be larger than observation values, which may be due to the existence of sand seams which were not found during soil investigation. 3. Useful data available for failure prediction of soft foundation can be secured by examining lateral displacement, settlement, exess pore water pressure and stress paths.

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