• Title/Summary/Keyword: Model Assessment

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A robust multi-objective localized outrigger layout assessment model under variable connecting control node and space deposition

  • Lee, Dongkyu;Lee, Jaehong;Kang, Joowon
    • Steel and Composite Structures
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    • v.33 no.6
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    • pp.767-776
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    • 2019
  • In this article, a simple and robust multi-objective assessment method to control design angles and node positions connected among steel outrigger truss members is proposed to approve both structural safety and economical cost. For given outrigger member layouts, the present method utilizes general-purpose prototypes of outrigger members, having resistance to withstand lateral load effects directly applied to tall buildings, which conform to variable connecting node and design space deposition. Outrigger layouts are set into several initial design conditions of height to width of an arbitrary given design space, i.e., variable design space. And then they are assessed in terms of a proposed multi-objective function optimizing both minimal total displacement and material quantity subjected to design impact factor indicating the importance of objectives. To evaluate the proposed multi-objective function, an analysis model uses a modified Maxwell-Mohr method, and an optimization model is defined by a ground structure assuming arbitrary discrete straight members. It provides a new robust assessment model from a local design point of view, as it may produce specific optimal prototypes of outrigger layouts corresponding to arbitrary height and width ratio of design space. Numerical examples verify the validity and robustness of the present assessment method for controlling prototypes of outrigger truss members considering a multi-objective optimization achieving structural safety and material cost.

Developing Information Security Management Model for SMEs: An Empirical Study (중소기업 정보보호관리 모델의 개발: 실증 연구)

  • Lee, Jung-Woo;Park, Jun-Gi;Lee, Zoon-Ky
    • Asia pacific journal of information systems
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    • v.15 no.1
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    • pp.115-133
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    • 2005
  • This study is to develop an information security management model(ISMM) for small and medium sized enterprises(SMEs). Based on extensive literature review, a five-pillar twelve-component reference ISMM is developed. The five pillars of SME's information security are: centralized decision making, ease of management, flexibility, agility and expandability. Twelve components are: scope & organization, security policy, resource assessment, risk assessment, implementation planning, control development, awareness training, monitoring, change management, auditing, maintenance and accident management. Subsequent survey designed and administered to expose experts' perception on the importance of these twelve components revealed that five out of tweleve components require relatively immediate attention than others, especially in SME's context. These five components are: scope and organization, resource assessment, auditing, change management, and incident management. Other seven components are policy, risk assessment, implementation planning, control development, awareness training, monitoring, and maintenance. It seems that resource limitation of SMEs directs their attention to ISMM activities that may not require a lot of resources. On the basis of these findings, a three-phase approach is developed and proposed here as an SME ISMM. Three phases are (1) foundation and promotion, (2) management and expansion, and (3) maturity. Implications of the model are discussed and suggestions are made for further research.

Application Cases of Risk Assessment for British Railtrack System (영국철도시스템에 적용된 리스크평가 사례)

  • Lee, Dong-Ha;Jeong, Gwang-Tae
    • Journal of the Ergonomics Society of Korea
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    • v.22 no.1
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    • pp.81-94
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    • 2003
  • The British railway safety research group has developed a risk assessment model for the railway infrastructure and major railway accidents. The major hazardous factors of the railway infrastructure were identified and classified in the model. The frequency rates of critical top events were predicted by the fault tree analysis method using failure data of the railway system components and ratings of railway maintenance experts, The consequences of critical top events were predicted by the event tree analysis method. They classified the Joss of accident due to railway system into personal. commercial and environmental damages. They also classified 110 hazardous event due to railway system into three categories. train accident. movement accident and non-movement accident. The risk assessment model of the British railway system has been designed to take full account of both the high frequency low consequence type events (events occurring routinely for which there is significant quantity of recorded data) and the low frequency high consequence events (events occurring rarely for which there is little recorded data). The results for each hazardous event were presented in terms of the frequency of occurrence (number of events/year) and the risk (number of equivalent fatalities per year).

Assessment of ride safety based on the wind-traffic-pavement-bridge coupled vibration

  • Yin, Xinfeng;Liu, Yang;Chen, S.R.
    • Wind and Structures
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    • v.24 no.3
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    • pp.287-306
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    • 2017
  • In the present study, a new assessment simulation of ride safety based on a new wind-traffic-pavement-bridge coupled vibration system is developed considering stochastic characteristics of traffic flow and bridge surface. Compared to existing simulation models, the new assessment simulation focuses on introducing the more realistic three-dimensional vehicle model, stochastic characteristics of traffic, vehicle accident criteria, and bridge surface conditions. A three-dimensional vehicle model with 24 degrees-of-freedoms (DOFs) is presented. A cellular automaton (CA) model and the surface roughness are introduced. The bridge deck pavement is modeled as a boundless Euler-Bernoulli beam supported on the Kelvin model. The wind-traffic-pavement-bridge coupled equations are established by combining the equations of both the vehicles in traffic, pavement, and bridge using the displacement and interaction force relationship at the patch contact. The numerical simulation shows that the proposed method can simulate rationally useful assessment and prevention information for traffic, and define appropriate safe driving speed limits for vulnerable vehicles under normal traffic and bridge surface conditions.

A Study on Development of Assessment Framework for Science Education Subjects in Science Teacher Training Program (사범대학 과학교육계학과의 교과교육 평가요목 개발에 관한 연구)

  • Lee, Wha-Kuk
    • Journal of The Korean Association For Science Education
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    • v.12 no.3
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    • pp.1-16
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    • 1992
  • The assessment framework of any edcational program is used not only as evaluation criteria of the program but as a guideline for development and implementation of the program. The aims of this paper are to develop and apply thoretical backgrounds and practical plans for the preparation of assessment framework of science education subjects in science teacher education program. The backgrounds, basic direction and practical methods of the study are described in introduction, and the natune and structure of science teachers competency, which forms the foundation of assessment framework for science teacher education, are discussed in section II. Current status of science education program m. the science education departments of the Colleges of Education is outlined in section III, and precise description of development pIans fat the assessment framework is described in section IV. Finally conclution and suggestions are presented, follow by a model assessment framework and syllabus for science education subjects prepared by applying the theory and plans developed in this study.The model assessment syllabus modified by workshops of science teacher educatorts is shown in the appendix.

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Objective Video Quality Assessment for Stereoscopic Video (스테레오 비디오의 객관적 화질평가 모델 연구)

  • Seo, Jung-Dong;Kim, Dong-Hyun;Sohn, Kwang-Hoon
    • Journal of Broadcast Engineering
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    • v.14 no.2
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    • pp.197-209
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    • 2009
  • Stereoscopic video delivers depth perception to users contrary to 2D video. Therefore, we need to develop a new video quality assessment model for stereoscopic video. In this paper, we propose a new method for objective assessment of stereoscopic video. The proposed method detects blocking artifacts and degradation in edge regions such as in conventional video quality assessment model. And it detects video quality difference between views using depth information for efficient quality prediction. We performed subjective assessment of stereoscopic video to check the performance of the proposed method, and we confirmed that the proposed algorithm is superior to the existing method in PSNR in respect to correlation with results of the subjective assessment.

Development of a reference framework to assess stylized human intrusion scenarios using GENII Version 2 considering design features of planned near-surface disposal facility in Korea

  • Kwon, Ki Nam;Cheong, Jae Hak
    • Nuclear Engineering and Technology
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    • v.51 no.6
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    • pp.1561-1574
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    • 2019
  • A standard form of six stylized human intrusion scenarios for a near-surface disposal facility (e.g. the planned Korean repository, Gyeongju Phase II) is proposed through re-categorization of totally thirty-one past cases reported in public literature. A reference assessment framework for inadvertent human intrusion is newly developed using GENII Version 2 conforming to the ICRP Publication 60 and thereafter. Calculated dose from the assessment framework is verified by comparing with hand calculation results for simplified model equations independently derived. Results from GENII Version 2 and 1.485 show inevitable differences, which is mainly attributed to the difference in the external dose assessment model. If intake dose coefficients in GENII Version 1.485 are modified, the difference can be reduced but still exist to an extent. Through deterministic and probabilistic sensitivity analysis, most affecting four parameters are derived and uncertainties of the parameters are quantified. It is expected that the reference assessment framework together with representative stylized scenarios can be used to do a human intrusion impact assessment for a specific repository using site-specific information. Especially, the past practice of human intrusion impact assessment using GENII Version 1.485 with or without modification may be replaced with the new assessment framework developed in this study.

The Environmental Impact Assessment of at Road Design in the Light of the Sense for the Real from the Virtual Reality (환경영향평가를 위한 VR기법으로 현실감을 고려한 도로설계)

  • Choi, Hyun
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.10 no.10
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    • pp.1842-1847
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    • 2006
  • This paper is the environmental impact assessment of at road design in the light of the sense for the real from the virtual reality. For In this papers, This study developed 3D-model and virtual reality contents by suggesting the environmental impact assessment based on GIS in the road design. Ant through this process, it's possible to visualize the environmental impact assessment by constructing the 3D-model and simulation. The 3D-model can be a method to show the road effectively by maximizing the road's shape visually after the construction. The main construction which composes polyhedron model that is generated from digital map and aerial photo is built by mapping the real texture, so the Sense for the Real was more heightened. Through this study, it must be made to shorten a long time exhausting period of conference and construct more real road after due scene consideration by specific and various low-cost strategy in the environmental impact assessment afterwards.

A Bone Age Assessment Method Based on Normalized Shape Model (정규화된 형상 모델을 이용한 뼈 나이 측정 방법)

  • Yoo, Ju-Woan;Lee, Jong-Min;Kim, Whoi-Yul
    • Journal of Korea Multimedia Society
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    • v.12 no.3
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    • pp.383-396
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    • 2009
  • Bone age assessment has been widely used in pediatrics to identify endocrine problems of children. Since the number of trained doctors is far less than the demands, there has been numerous requests for automatic estimation of bone age. Therefore, in this paper, we propose an automatic bone age assessment method that utilizes pattern classification techniques. The proposed method consists of three modules; a finger segmentation module, a normalized shape model generation module and a bone age estimation module. The finger segmentation module segments fingers and epiphyseal regions by means of various image processing algorithms. The shape model abstraction module employ ASM to improves the accuracy of feature extraction for bone age estimation. In addition, SVM is used for estimation of bone age. Features for the estimation include the length of bone and the ratios of bone length. We evaluated the performance of the proposed method through statistical analysis by comparing the bone age assessment results by clinical experts and the proposed automatic method. Through the experimental results, the mean error of the assessment was 0.679 year, which was better than the average error acceptable in clinical practice.

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Exploration of the Direction for the Practice of Process-Focused Assessment (과정 중심 평가의 실행을 위한 방향 탐색)

  • Lee, Kyeong-Hwa;Kang, Hyun Young;Ko, Eun-Sung;Lee, Dong-Hwan;Shin, Bomi;Lee, Hwan Chul;Kim, Sun Hee
    • Journal of Educational Research in Mathematics
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    • v.26 no.4
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    • pp.819-834
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    • 2016
  • As a method to lead a change in mathematics education, recently reformation of assessment appears as a concept of process-focused assessment. Process-focused assessment is the concept that 2015 revised mathematics curriculum aims for, which is promoted also in policy. This research suggested a significance of process-focused assessment that has not been determined in conceptualization and the practical model. For this, this research investigated the content of the assessment on 2015 revised mathematics curriculum, and explored process-focused assessment based on the recent education assessment theory and research. Also, we suggested a model of practical plan by investigating the condition to perform the process-focused assessment. This research could take a basic role to practice process-focused assessment and investigate the concrete plan in the mathematics class field.