• Title/Summary/Keyword: Evaluation Models

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Reliability and Availability Modeling of the MIN (Multistage Interconnection Network) System (신뢰도를 고려한 다단계 스위치 망의 성능 분석)

  • 이강원
    • Korean Management Science Review
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    • v.15 no.1
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    • pp.63-76
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    • 1998
  • Reliability evaluation methodologies of the multipath MIN system are reviewed and critically compared. Some guidelines are proposed to select efficient evaluation method for the system designers to use. Considering the switch failure and repair characteristics of the MIN system, three types of Markov models are proposed for the MIN system availability models. These models can be used for the MIN performance analysis. The performance of the MIN system are supposed to vary according to the failure state of the system.

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Performance Evaluation of HNCP Home Network Using Stochastic Activity Network Models (Stochastic Activity Network 모델을 이용한 HNCP 홈 네트워트 성능 평가)

  • 이재민;명관주;이감록;전요셉;권욱현
    • Proceedings of the IEEK Conference
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    • 2003.11c
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    • pp.183-186
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    • 2003
  • In this paper, performance evaluation of HNCP home network is using stochastic activity network models is proposed. HNCP is a home network protocol for controling and monitoring home appliances using power line communication. a CSMA/CA with packet drop method is used in HNCP MAC layer. Using the proposed stochastic activity network models. performances of HNCP home networks with error-free environment and error environment are evaluated.

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An Investigation on Characteristics of Program Evaluation Model according to Research Paradigm (연구 패러다임에 따른 프로그램 평가모형의 특징 고찰)

  • Hong, Jeong-Whan;WON, Hyo-Heon
    • Journal of Fisheries and Marine Sciences Education
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    • v.29 no.3
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    • pp.941-951
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    • 2017
  • The purpose of this study is to investigate the characteristics of the research paradigm and to explore the characteristics and limitations of the representative evaluation models belonging to each paradigm. The research paradigm is Positivism, Interpretivism, Critical Theory, and Postmodernism. The evaluation models that represent each paradigm include Objective-oriented evaluation model, Forth generation evaluation model, Empowerment evaluation model, Connoisseurship & Criticism model. The characteristics of each evaluation model reflects the characteristics of their own research paradigm.

European Approaches to Work-Related Stress: A Critical Review on Risk Evaluation

  • Zoni, Silvia;Lucchini, Roberto G.
    • Safety and Health at Work
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    • v.3 no.1
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    • pp.43-49
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    • 2012
  • In recent years, various international organizations have raised awareness regarding psychosocial risks and work-related stress. European stakeholders have also taken action on these issues by producing important documents, such as position papers and government regulations, which are reviewed in this article. In particular, 4 European models that have been developed for the assessment and management of work-related stress are considered here. Although important advances have been made in the understanding of work-related stress, there are still gaps in the translation of this knowledge into effective practice at the enterprise level. There are additional problems regarding the methodology in the evaluation of work-related stress. The European models described in this article are based on holistic, global and participatory approaches, where the active role of and involvement of workers are always emphasized. The limitations of these models are in the lack of clarity on preventive intervention and, for two of them, the lack of instrument standardization for risk evaluation. The comparison among the European models to approach work-related stress, although with limitations and socio-cultural differences, offers the possibility for the development of a social dialogue that is important in defining the correct and practical methodology for work stress evaluation and prevention.

Seismic Behavior of Liquid Storage Tanks Using Complex and Simple Analytical Models

  • Nabin, Raj Chaulagain;Sun, Chang Ho;Kim, Ick Hyun
    • Journal of the Earthquake Engineering Society of Korea
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    • v.22 no.7
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    • pp.401-409
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    • 2018
  • Performance-based seismic evaluation is usually done by considering simplified models for the liquid storage tanks therefore, it is important to validate those simplified models before conducting such evaluation. The purpose of this study is to compare the seismic response results of the FSI (fluid-structure interaction) model and the simplified models for the cylindrical liquid storage tanks and to verify the applicability of the simplified models for estimating failure probability. Seismic analyses were carried out for two types of storage tanks with different aspect ratios (H/D) of 0.45 and 0.86. FSI model represents detailed 3D fluid-structure interaction model and simplified models are modeled as cantilever mass-spring model, frame type mass-spring model and shell type mass-spring model, considering impulsive and convective components. Seismic analyses were performed with modal analysis followed by time history analysis. Analysis results from all the models were verified by comparing with the results calculated by the code and literature. The results from simplified models show good agreement with the ones from detailed FSI model and calculated results from code and literature, confirming that all three types of simplified models are very valid for conducting failure probability analysis of the cylindrical liquid storage tanks.

Seismic Performance Evaluation of Unreinforced Masonry Buildings Retrofitted by Strengthening External Walls (외부벽체 강도증진형 보강이 적용된 비보강 조적조 건물의 내진성능평가)

  • Seol, Yun Jeong;Park, Ji-Hun
    • Journal of the Earthquake Engineering Society of Korea
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    • v.24 no.2
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    • pp.77-86
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    • 2020
  • Nonlinear static analysis and preliminary evaluation were performed in this study to evaluate the seismic performance of unreinforced masonry buildings subjected to various soil conditions based on the revised Korean Building Code. Preliminary evaluation scores and nonlinear static analyses indicated that all buildings were susceptible to collapse and did not reach their target performance. Therefore, retrofit of those building models was carried out through a systematic procedure to determine areas to be strengthened. It was possible to make most building models satisfy performance objectives through the reinforcement alone of damaged external shear walls. However, the application of a preliminary evaluation procedure to retrofit design was found to be too conservative because all the retrofitted building models verified with nonlinear static analysis failed to satisfy performance objectives. Therefore, it is possible to economically retrofit unreinforced masonry buildings through the fortification of external walls if a simple evaluation procedure that can efficiently specify vulnerable parts is developed.

Semiparametric Evaluation of Environmental Goods: Local Linear Model Approach

  • Jeong, Ki-Ho
    • Journal of the Korean Data and Information Science Society
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    • v.14 no.2
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    • pp.209-216
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    • 2003
  • Contingent valuation method (CVM) is a main evaluation method of nonmarket goods for which markets either do not exist at all or do exist only incompletely; an example is environmental good. A dichotomous choice approach, the most popular type of CVM in environmental economics, employs binary discrete choice models as statistical estimation models. In this paper, we propose a semiparametric dichotomous choice CVM method using local linear model of Fan and Gijbels (1996) in which probability distribution of error term is specified parametrically but latent structural function is specified nonparametrically. The computation procedures of the proposed method are illustrated with a simple design of simulations.

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Evaluation of Location Suitability for Protected Horticulutre (시설원예의 입지적성평가)

  • 황한철;김정식;심옥자;김희수
    • Proceedings of the Korean Society of Agricultural Engineers Conference
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    • 1999.10c
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    • pp.348-353
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    • 1999
  • It is necessary to evaluate the location suitability for protected horiculture to plan new protected horticulture facilities in rural areas. Evaluation models for location suitability of protected horticulture in three selected regions ; suburban , plain mountainous were constructed by method of analytic hierarchy process (AHP). Evaluation models were to three case study areas,location characteristics of protected horticulture were shown in each regional features.

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Development and Evaluation of Simple Regression Model and Multiple Regression Model for TOC Contentation Estimation in Stream Flow (하천수내 TOC 농도 추정을 위한 단순회귀모형과 다중회귀모형의 개발과 평가)

  • Jung, Jaewoon;Cho, Sohyun;Choi, Jinhee;Kim, Kapsoon;Jung, Soojung;Lim, Byungjin
    • Journal of Korean Society on Water Environment
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    • v.29 no.5
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    • pp.625-629
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    • 2013
  • The objective of this study is to develop and evaluate simple and multiple regression models for Total Organic Carbon (TOC) concentration estimation in stream flow. For development (using water quality data in 2012) and evaluation (using water quality data in 2011) of regression models, we used water quality data from downstream of Yeongsan river basin during 2011 and 2012, and correlation analysis between TOC and water quality parameters was conducted. The concentrations of TOC were positively correlated with Chemical Oxygen Demand (COD), Biochemical Oxygen Demand (BOD), TN (Total Nitrogen), Water Temperature (WT) and Electric Conductivity (EC). From these results, simple and multiple regression models for TOC estimation were developed as follows : $TOC=0.5809{\times}BOD+3.1557$, $TOC=0.4365{\times}COD+1.3731$. As a result of the application evaluation of the developed regression models, the multiple regression model was found to estimate TOC better than simple regression models.