• 제목/요약/키워드: observation-based method

검색결과 1,122건 처리시간 0.028초

Simultaneous Estimation of the Birth and Death Rate of the Linear Growth Birth and Death Process Based on Discrete Time Observation

  • ChangHyuck Oh
    • Communications for Statistical Applications and Methods
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    • 제3권1호
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    • pp.235-242
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    • 1996
  • When the linear growth birth and death process observed at a set of equidistant time points, McNeil and Weiss (1997) present a method for simultaneously estimating the Malthusian parameter and the sum of the two parameters under wery restricted assumptions using a diffusion approximation. This article suggests a method, which does not require the restrictions given by Weiss, for estimating simultaneously the Malthusian parameter and the sum of the two parameters.

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A DYNAMIC GRAPHICAL METHOD FOR REGRESSION DIAGNOSTICS

  • Park, Sung H.;Kim, You H.
    • 품질경영학회지
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    • 제19권2호
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    • pp.1-16
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    • 1991
  • Recently, Cook and Weisberg(l989) presented dynamic graphics for regression diagnostics. They suggested animating graphics which could aid to understanding the effects of adding a variable to a model. In this paper, using the Cook and Weisberg's idea of animation, we propose a dynamic graphical method for residuals to display the effects of removing an observation from a model. Based on the information obtained from these animating graphics, it is possible to see the influence of outliers on influencial observations for regression diagnostics.

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Robust Constrained Predictive Control without On-line Optimizations

  • Lee, Y. I.;B. Kouvaritakis
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2001년도 ICCAS
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    • pp.27.4-27
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    • 2001
  • A stabilizing control method for linear systems with model uncertainties and hard input constraints is developed, which does not require on-line optimizations. This work is motivated by the constrained robust MPC(CRMPC) approach [3] which adopts the dual mode prediction strategy (i.e. free control moves and invariant set) and minimizes a worst case performance criterion. Based on the observation that, a feasible control sequence for a particular state can be found as a linear combination of feasible sequences for other states, we suggest a stabilizing control algorithm providing sub-optimal and feasible control sequences using pre-computed optimal sequences for some canonical states. The on-line computation of the proposed method reduces to simple matrix multiplication.

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Automated Analysis of Scaffold Joint Installation Status of UAV-Acquired Images

  • Paik, Sunwoong;Kim, Yohan;Kim, Juhyeon;Kim, Hyoungkwan
    • 국제학술발표논문집
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    • The 9th International Conference on Construction Engineering and Project Management
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    • pp.871-876
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    • 2022
  • In the construction industry, fatal accidents related to scaffolds frequently occur. To prevent such accidents, scaffolds should be carefully monitored for their safety status. However, manual observation of scaffolds is time-consuming and labor-intensive. This paper proposes a method that automatically analyzes the installation status of scaffold joints based on images acquired from a Unmanned Aerial Vehicle (UAV). Using a deep learning-based object detection algorithm (YOLOv5), scaffold joints and joint components are detected. Based on the detection result, a two-stage rule-based classifier is used to analyze the joint installation status. Experimental results show that joints can be classified as safe or unsafe with 98.2 % and 85.7 % F1-scores, respectively. These results indicate that the proposed method can effectively analyze the joint installation status in UAV-acquired scaffold images.

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Robust inference for linear regression model based on weighted least squares

  • 박진표
    • Journal of the Korean Data and Information Science Society
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    • 제13권2호
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    • pp.271-284
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    • 2002
  • In this paper we consider the robust inference for the parameter of linear regression model based on weighted least squares. First we consider the sequential test of multiple outliers. Next we suggest the way to assign a weight to each observation $(x_i,\;y_i)$ and recommend the robust inference for linear model. Finally, to check the performance of confidence interval for the slope using proposed method, we conducted a Monte Carlo simulation and presented some numerical results and examples.

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Perceptron 알고리즘을 이용한 가중 순서 통게 필터의 설계 (A Design Method for Weighted Order Statistic Filters Based on the Perceotron Algorithm)

  • 정병장;이용훈
    • 전자공학회논문지B
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    • 제30B권6호
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    • pp.1-6
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    • 1993
  • In this paper, we observe that the design of optimal weighted order statistic(WOS) filters minimizing the mean absolute error criterion can be though of as a two-class linear classification problem. Based on this observation, the perceptron algorithm is applied to design WOS filters. It is shown, through experiments, that the perceptron algorithm can find optimal or near optimal WOS filters in practical situations.

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한천유역의 수문학적 특성을 고려한 관측자료 기반 홍수량 산정 (Estimation of Flood Discharge Based on Observation Data Considering the Hydrological Characteristics of the Han Stream Basin in Jeju Island)

  • 양성기;김민철;강보성;김용석;강명수
    • 한국환경과학회지
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    • 제26권12호
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    • pp.1321-1331
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    • 2017
  • This study reviewed the applicability of the existing flood discharge calculation method on Jeju Island Han Stream and compared this method with observation results by improving the mediating variables for the Han Stream. The results were as follows. First, when the rain-discharge status of the Han Stream was analyzed using the flood discharge calculation method of the existing design (2012), the result was smaller than the observed flood discharge and the flood hydrograph differed. The result of the flood discharge calculation corrected for the curve number based on the terrain gradient showed an improvement of 1.47 - 6.47% from the existing flood discharge, and flood discharge was improved by 4.39 - 16.67% after applying the new reached time. In addition, the sub-basin was set separately to calculate the flood discharge, which yielded an improvement of 9.92 - 32.96% from the existing method. In particular, the steepness and rainfall-discharge characteristics of Han Stream were considered in the reaching time, and the sub-basin was separated to calculate the flood discharge, which resulted in an error rate of -8.77 to 8.71%, showing a large improvement of 7.31 - 28.79% from the existing method. The flood hydrograph also showed a similar tendency.

관측 자료를 활용한 지진가속도 시간이력 추정방법 제안 (Proposal of Acceleration Time History Prediction Method Based on Seismic Observation Data)

  • 이경석;안진희;박재봉;최형석
    • 한국구조물진단유지관리공학회 논문집
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    • 제24권2호
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    • pp.15-22
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    • 2020
  • 본 논문에서는 지진발생 후 임의 위치에서 발생된 지진가속도 시간이력을 추정하기 위하여 기상청 지진관측소 계측자료를 활용하는 방법을 제안하였으며, 국내에서 발생한 지진기록을 이용하여 제안한 응답스펙트럼 및 시간이력 추정 방법의 적용성을 평가하였다. 임의 관측소에서 계측된 결과를 인근 관측소 자료를 이용하여 추정하는 방법으로 제안방법을 검증한 결과, 지반정보 없이도 해당 관측소 위치의 지진가속도 응답스펙트럼 및 시간이력을 낮은 수준의 오차로 추정할 수 있었으며, 특히 시간이력의 경우 형상 및 위상의 변화에 큰 차이가 없음을 확인할 수 있는 등 제안된 방법이 임의 위치에서의 지진가속도 시간이력을 추정하는데 유효함을 확인할 수 있었다.

해풍(海風)을 이용한 하계(夏季) 도시열환경(都市熱環境)의 풍도(風道)계획과 인체의 쾌적성에 관한 연구 (Estimating the cooling effect of see breeze along canals and outdoor thermal comfort on urban heat load in summer)

  • 정창원;윤인;최영식
    • 한국산업융합학회 논문집
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    • 제2권1호
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    • pp.19-25
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    • 1999
  • A new urban design method from the viewpoint of climate is considered to be desired for urban life. The authors verified on an environmental planning based on new urban design concept which introduced the effect of sea breeze blowing along canals. The field observation of urban thermal environment were carried out to examine the cooling effects of a river through city. The observations were conducted to find the effect of a sea breeze and climate in summer along canals. Effective distance from the sea and cooling effect of the sea breeze on urban temperature was analyzed. The thermal index using outdoor environment was modified with New Effective Temperature ET*. On the basis of the observation. Human thermal comfort is relieved and affected by sea breeze blowing along canals. The canals were utilized as the trail on which sea breeze blows towards the center of city. From these results, The wind trail is one of the effective passive design method from the viewpoint of urban climate.

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화상 분석을 통한 선박 방오도료의 성능 평가 (Image Analysis Method for the Performance Evaluation of Marine Antifouling Coatings)

  • 박현;전호환;이인원
    • 한국가시화정보학회지
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    • 제11권2호
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    • pp.18-26
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    • 2013
  • An accurate and reliable performance evaluation technique is indispensable for the development of marine antifouling coatings. The existing standard practice is however, based on the visual observation of biofouling settlement area, which is prone to the subjective judgment of the inspector. In spite of the above mentioned importance, a systematic and objective fouling evaluation technique has not yet been introduced. In this study, a novel quantitative antifouling performance evaluation method for marine antifouling paints is devised based on the image analysis of panel immersion test results. The present image analysis method is to quantify settlement area for each fouling category by distinctive color. The fouling categories are set as unfouled, biofilm, green algae, brown algae, calcareous animal and spongy animal with specific HSL (Hue, Saturation, Lightness) color ranges. In order to assess the effectiveness of the proposed method, static immersion tests for three antifouling coatings were undertaken for two years.