• Title/Summary/Keyword: uncertain data

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Occurrence of Sooty Blotch and Flyspeck Disease on Sweet Persimmon in Korea

  • Kwon, Jin-Hyeuk;Kim, Jin-Woo;Choi, Ok-Hee;Gang, Guen-Hye;Kwak, Youn-Sig
    • Mycobiology
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    • v.40 no.3
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    • pp.210-213
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    • 2012
  • Sooty blotch and flyspeck (SBFS), a disease caused by a complex of fungi, results in substantial economic losses for commercial growers of sweet persimmon (Diospyros kaki L.) in Korea. However, many species causing SBFS in Korea have not been identified and sources of inoculum are uncertain. Based on mycological characteristics, pathogenicity, and molecular data, the causal fungi were identified as Dissoconium sp. and Zygophiala wisconsinensis. This is the first report of SBFS of sweet persimmon in Korea.

Project Team Leader's Roles and Team Performance (프로젝트 팀 리더의 역할과 팀성과)

  • 김영배;차종석
    • Journal of the Korean Operations Research and Management Science Society
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    • v.19 no.1
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    • pp.123-144
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    • 1994
  • This Study has empirically examined the relationship between the role of R & D project leaders and their team performance using data from 87 project teams in 6 R & d organizations. The results reveal that : 1) R & D project leaders play five different roles for performing their jobs-strategic plannar, team builder, gatekeeper, expert and champion : 2) all but the champion role of leaders are positively associated with project team performance unless they have too short team tenure to materialize their role efforts : 3) However, the relationship between the role of leaders and project team performance varies according to characteristics of their team and project tasks. More specifically, it becomes more important for leaders to focus on gatekeeping and championing roles as their team gats older. Team building role of leaders is more important for higher performance of relatively certain R & D projects, while for uncertain R & D projects gatekeeping role appears to be more important.

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R & D 프로젝트 팀의 과업 불확실성, 조직구조, 커뮤니케이선 유형 - 구조적 상황이론

  • ;;Kim, Youngbae
    • Journal of the Korean Operations Research and Management Science Society
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    • v.17 no.2
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    • pp.53-90
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    • 1992
  • THis study examines a contingency relationship between task uncertainty and structure of project teams in conjunction with the leader-member communication patterns. Multivariate analyses are used to analyze the data from 63 R & D project teams of research laboratory in a large manufacturing corporation. Major findings for this study can be summarized as follows. First, project teams with an organic structure are found to yield high performance when task uncertainty is high, while project teams with a mechanistic structure achieve high performance when their tasks are relatively certain. Second, patterns of leader-member comunication are significantly associated with both task uncertainty and structural characteristics of project teams. This implies that leaders of project teams communicate with their members in more conslutative manner when their tasks are uncertain or when their team structure exhibits organic characteristics. Finally, task uncertainty playus a significant moderating role in the relationship between consultative communication patterns and performance of project teams. Based upon these findings, this study offers several theoretical, practical, and methodological implications.

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Design of Incoming Ballistic Missile Tracking Systems Using Extended Robust Kalman Filter (확장 강인 칼만 필터를 이용한 접근 탄도 미사일 추적 시스템 설계)

  • 이현석;나원상;진승희;윤태성;박진배
    • 제어로봇시스템학회:학술대회논문집
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    • 2000.10a
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    • pp.188-188
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    • 2000
  • The most important problem in target tracking can be said to be modeling the tracking system correctly. Although the simple linear dynamic equation for this model has used until now, the satisfactory performance could not be obtained owing to uncertainties of the real systems in the case of designing the filters baged on the dynamic equations. In this paper, we propose the extended robust Kalman filter (ERKF) which can be applied to the real target tracking system with the parameter uncertainties. A nonlinear dynamic equation with parameter uncertainties is used to express the uncertain system model mathematically, and a measurement equation is represented by a nonlinear equation to show data from the radar in a Cartesian coordinate frame. To solve the robust nonlinear filtering problem, we derive the extended robust Kalman filter equation using the Krein space approach and sum quadratic constraint. We show the proposed filter has better performance than the existing extended Kalman filter (EKF) via 3-dimensional target tracking example.

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The Status Quo and Direction of Development of Environmental Impact Assessment System in Korea (우리나라 환경영향평가제도의 현주소와 발전방향에 관한 연구)

  • Choi, Joon-Gyu
    • Journal of Environmental Impact Assessment
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    • v.9 no.2
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    • pp.155-161
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    • 2000
  • Environmental impact assessment(EIA), the only preventive system to manage development projects destroying the nature and ecosystem systematically, has been accomplished since the late 1970. EIA connotes intrinsic limits predicting uncertain future with the aid of present data. Furthermore, EIA has been used as not decision-making tools but regulatory means. Therefore, EIA has been criticized severely. In order to present direction of development of EIA, we analyzed problems of management of EIA, and concluded measures as follows are needed. 1. Control of investigation of environmental impact statements 2. Development of evaluating methods and publication 3. Fostering of institute for research and investigation of EIA 4. Construction of harmony of environment and development 5. Upgrade of state of proxy executing EIA.

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Robust Capacity Planning in Network Coding under Demand Uncertainty

  • Ghasvari, Hossien;Raayatpanah, Mohammad Ali
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.9 no.8
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    • pp.2840-2853
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    • 2015
  • A major challenge in network service providers is to provide adequate resources in service level agreements based on forecasts of future demands. In this paper, we address the problem of capacity provisioning in a network subject to demand uncertainty such that a network coded multicast is applied as the data delivery mechanism with limited budget to purchase extra capacity. We address some particular type of uncertainty sets that obtain a tractable constrained capacity provisioning problem. For this reason, we first formulate a mathematical model for the problem under uncertain demand. Then, a robust optimization model is proposed for the problem to optimize the worst-case system performance. The robustness and effectiveness of the developed model are demonstrated by numerical results. The robust solution achieves more than 10% reduction and is better than the deterministic solution in the worst case.

Stochastic upscaling via linear Bayesian updating

  • Sarfaraz, Sadiq M.;Rosic, Bojana V.;Matthies, Hermann G.;Ibrahimbegovic, Adnan
    • Coupled systems mechanics
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    • v.7 no.2
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    • pp.211-232
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    • 2018
  • In this work we present an upscaling technique for multi-scale computations based on a stochastic model calibration technique. We consider a coarse-scale continuum material model described in the framework of generalized standard materials. The model parameters are considered uncertain, and are determined in a Bayesian framework for the given fine scale data in a form of stored energy and dissipation potential. The proposed stochastic upscaling approach is independent w.r.t. the choice of models on coarse and fine scales. Simple numerical examples are shown to demonstrate the ability of the proposed approach to calibrate coarse scale elastic and inelastic material parameters.

STUDY ON DYNAMIC BEHAVIOUR IN 3PB DUCTILE STEEL SPECIMEN APPLIED BY THE IMPACT LOAD

  • HAN M. S.;CHO J. U.;BERGMARK A.
    • International Journal of Automotive Technology
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    • v.6 no.3
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    • pp.229-234
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    • 2005
  • The dynamic crack growth in ductile steel is investigated by means of the impact loaded 3 point bending (3PB) specimens. Results from experiments and numerical simulations are compared to each other. A modified 3PB specimen designed with the reduced width at its ends has been developed in order to avoid the initial compressive loading of the crack tip and also to avoid the uncertain boundary conditions at the impact heads. Numerical simulations of the experiments are made by using a finite element method (FEM) code, ABAQUS. The high speed photography is used to obtain the crack growth and the data of the crack tip opening displacement (CTOD). The direct measurements of the relative rotations of two specimen halves are made by using the Moire interference pattern.

A Study on Design of Production System Using Multiple Characteristics Robust Design in Uncertain Environment (불확실한 환경에서의 다특성치 강건설계를 이용한 생산시스템 설계에 관한 연구)

  • 양광모;서장훈;박진홍;강경식
    • Proceedings of the Safety Management and Science Conference
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    • 2004.05a
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    • pp.61-65
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    • 2004
  • As technique that can contribute in quality improvement in design process to overcome shortcoming of traditional quality control, call design or development department quality control activity that is achieved to reduce gun damage shuddering at circle minimizing change or side effect of product performance as off-line quality control. This paper discuss optimal process design of investment projects expansion and replacement investment on each line or individual in the production. Generally optimal plant design has add to a few method by Subsidiary means with use a especial method. And then in this paper, a Robust design is presented, which may be effective to the processes appraisal or improvement. We propose that should make a optimal plant design model for reducing field failure rate to assign by real data on different factors in plant system. Using this model, robust design of taguchi method used in this comprehensive method for reducing field failure rate in plant system.

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Deciding Optimizing Uncertain Environment Factor and Application to Selecting plan data communication (불확실 환경상태 최적계수 결정법 및 평면 데이터 조합선택에의 응용)

  • 진현수;이상훈;홍유식
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 2000.05a
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    • pp.191-194
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    • 2000
  • 최근의 삼풍백화점 붕괴사고 및 성수대교사고 등 대형사고의 원인을 살펴보면 건물의 안전진단 미비와 구조물의 안전관리 진단판정미비로 건축물의 붕괴를 예측하지 못한 결과이다. 이는 모든 불확실 시스템의 상태를 적당한 항목으로 판정 정규화한 계수값으로 나타내어 예방하지 못한 결과이다. 비단건축물 시스템뿐 아니라 실존 가시물(可視物)과 비가시물(悲歌視物)에 대해서도 비결정 상황의 상태표시계수를 예측하여 정규값으로 나타낼 필요가 있다. 즉, 교통도로의 교통량 특정, 통신신호의 수신율 측정 등을 최적화 예측할 수가 있게된다. 본 논문에서는 환경 및 시스템 출력값에 표시하여 어떤 결과를 가져오는지 확인하기 위하여 평면 상의 임의의 데이터의 조합으로부터 특정 데이타를 선택 최적화하는 과정을 실험화 하였다.

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