• Title/Summary/Keyword: Assessment Criterion

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Ship Collision Risk Assessment for Bridges (교량의 선박충돌위험도 평가)

  • Lee, Seong Lo;Bae, Yong Gwi
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.26 no.1A
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    • pp.1-9
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    • 2006
  • An analysis of the annual frequency of collapse(AF) is performed for each bridge pier exposed to ship collision. From this analysis, the impact lateral resistance can be determined for each pier. The bridge pier impact resistance is selected using a probability-based analysis procedure in which the predicted annual frequency of bridge collapse, AF, from the ship collision risk assessment is compared to an acceptance criterion. The analysis procedure is an iterative process in which a trial impact resistance is selected for a bridge component and a computed AF is compared to the acceptance criterion, and revisions to the analysis variables are made as necessary to achieve compliance. The distribution of the AF acceptance criterion among the exposed piers is generally based on the designer's judgment. In this study, the acceptance criterion is allocated to each pier using allocation weights based on the previous predictions. To determine the design impact lateral resistance of bridge components such pylon and pier, the numerical analysis is performed iteratively with the analysis variable of impact resistance ratio of pylon to pier. The design impact lateral resistance can vary greatly among the components of the same bridge, depending upon the waterway geometry, available water depth, bridge geometry, and vessel traffic characteristics. More researches on the allocation model of AF and the determination of impact resistance are required.

Development of Forests Ecosystem Assessment Technique of Environmental Impact Assessment(I) : In the Case of the Sanchong Pumping-up Power Plant of Mt. Chiri (환경영향평가중 삼림생태계 평가기법 개발 (I) : 지리산 산청 양수발전소 건설예정지를 중심으로)

  • Choi, Song-Hyun;Lee, Kyong-Jae
    • Journal of Environmental Impact Assessment
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    • v.4 no.2
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    • pp.71-91
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    • 1995
  • In order to develop an appropriate set of criteria applicable for environmental impact assessment (EIA) of natural forest 8 items are proposed. The criteria are vegetation distribution area (DA), distribution pattern (DP), size (S), diameter of breast height of tree (DBH), humus (H), sustainment (ST), successional stage (SS) and impact of adjacent ecosystem (IAE), Each criterion has an interval which minimum 1 score to maximum 5 score Forest Evaluation Index (FEI) was obtained as the sum of 8 criteria value. Above 70% is considered to be absolutely conservative and from 50% to 70% range of total score is to be considered conservative. In the case of the Sancho˘ng Pumping-up Power Plant of Mt. Chiri, 8 criteria were applied base on actual vegetation map. Pinus densiflora community got 73%(29 scores) and Quercus variabilis - Q. serrata community got 60%(24 scores). This may be said that this local vegetation has high ecological potentiality. These criteria cannot always be absolutely evaluation tool. So it is expected to take the more time to be developed further, and holistically added by the other field such as fauna, geological feature etc.

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Decision Making of Improvement Priority by Deterioration Risk Assessment of Water Supply Infrastructures (물공급시설의 노후 위험도 평가를 통한 개선 우선순위 결정)

  • Chae, Soo-Kwon;Lee, Dae-Jong;Kim, Ju-Hwan
    • Journal of Environmental Impact Assessment
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    • v.18 no.6
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    • pp.367-376
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    • 2009
  • This paper proposes an application methodology of AHP(Analytic Hierarchy Process) based decision making theory for improvement priority by assessment of various risk factors affecting on deterioration of water supply systems, as major social infrastructure. AHP method is organized with three level of hierarchy which is introduced for multi-criteria decision making in this study. In the first level, assessment outputs are calculated by AHP for each affecting factor. In the second level, criteria are estimated by using assessment results with respect to structural and environmental factors. Consequently, ranking decision is performed in the third level. In order to present the effectiveness, a proposed method is compared with FCP(Fuzzy Composite Programming) for decision making. Since the results of the proposed method show better performance with consistent results, it can be applied as an efficient information for the determination for improvement priority of the study infrastructure.

Ship Collision Risk Analysis of Bridge Piers (선박충돌로 인한 교각의 위험도 분석)

  • Lee, Seong-Lo;Bae, Yong-Gwi
    • Journal of the Korea institute for structural maintenance and inspection
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    • v.9 no.4
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    • pp.169-176
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    • 2005
  • An analysis of the annual frequency of collapse(AF) is performed for each bridge pier exposed to ship collision. From this analysis, the impact lateral resistance can be determined for each pier. The bridge pier impact resistance is selected using a probability-based analysis procedure in which the predicted annual frequency of bridge collapse, AF, from the ship collision risk assessment is compared to an acceptance criterion. The analysis procedure is an iterative process in which a trial impact resistance is selected for a bridge component and a computed AF is compared to the acceptance criterion, and revisions to the analysis variables are made as necessary to achieve compliance. The distribution of the AF acceptance criterion among the exposed piers is generally based on the designer's judgment. In this study, the acceptance criterion is allocated to each pier using allocation weights based on the previous predictions.

Failure Probability Evaluation of Pressure Tube using the Probabilistic Fracture Mechanics (확률론적 파괴역학 기법을 이용한 압력관의 파손확률 평가)

  • Son, Jong-Dong;Oh, Dong-Joon
    • Journal of the Korean Society of Safety
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    • v.22 no.4
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    • pp.7-12
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    • 2007
  • In order to evaluate the integrity of Zr-2.5Nb pressure tubes, probabilistic fracture mechanics(PFM) approach was employed. Failure assessment diagram(FAD), plastic collapses, and critical crack lengths(CCL) were used for evaluating the failure probability as failure criteria. The Kr-FAD as failure assessment diagram was used because fracture of pressure tubes occurred in brittle manner due to hydrogen embrittlement of material by deuterium fluence. The probabilistic integrity evaluation observed AECL procedures and used fracture toughness parameters of EPRI and recently announced theory. In conclusion, the probabilistic approach using the Kr-FAD made it possible to determine major failure criterion in the pressure tube integrity evaluation.

Development and Validation of an Observation Scale for Day Care Programs (어린이집 프로그램 관찰척도의 개발과 타당화)

  • Rhee, Unhai;Choi, Hye Yeong;Song, Hye Rin;Shin, Hye Young
    • Korean Journal of Child Studies
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    • v.24 no.3
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    • pp.135-149
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    • 2003
  • This study aimed to develop an observation scale for assessing the quality of day care programs and to examine reliability and validity of the scale. Instruments included 3 self-assessment scales, the Evaluation Scale for Early Childhood Programs and an observation scale completed by 8 trained observers in 89 day care sites. Item analysis indicated that most items were acceptable in terms of item discrimination and item response distribution. Cronbach ${\alpha}^{\prime}s$ and inter-observer reliability were relatively high. Validity of the scale was evidenced by correlations between the observation scale and the criterion measure and inter-correlations among sub-areas of the observation scale. Scores on the observation scale were validated by quality ratings from self-assessment scores.

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Durability Assessment of a Control Arm Using 1/4 Car Test (1/4차량 시험을 통한 상부 컨트롤 암의 내구성 평가)

  • Ha, Min-Soo;Son, Hwan-Jung;Kim, Jong-Kyu;Park, Young-Chul
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.9 no.6
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    • pp.16-20
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    • 2010
  • This study proposes a structural design method for the upper control arm installed at the rear side of a SUV. The weight of control arm can be reduced by applying the design. In this research, the former includes optimization technology, and the latter the technologies for selecting aluminum as a steel-substitute material. Strength assessment is the most important design criterion in the structural design of a control arm. At the proto design stage of a new control arm, FE (finite element) analysis is often utilized to predict its strength. In this study, the kriging interpolation method is adopted to obtain the minimum weight satisfying the strength constraint and durability criteria. The optimum results determined from the in-house program are compared with those of ANSYS WORKBENCH. The durability assessment is obtained by a index of fatigue durability and trial & error method, MSC. Fatigue program.

Testing the Crierion-related Validity of a Mental Health Assessment Tool in Kerean Adult (일 정신건강 사정도구의 준거 타당도 검증)

  • Go, Seong-Hui
    • The Korean Nurse
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    • v.30 no.4
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    • pp.61-68
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    • 1991
  • This study was conducted to testing the criterion - related validity of a mental health assessment tool which developed based on a korean culture. Criteria scale for this tool were MMPI and CMI(M - R). The study subject were 100 male and female aged 20 or more with quota sampling. The data was collected from August 16. to August 26. 1989. The data obtained from 85 subjects were analysed using S.P.S.S.(Stastistical Package for the Social Science). As a result, there are no significant correlation between Mental Health Assessment Tool and MMPI and CMI except Mf(Masculinity-Feminity) Subscale of MMPI. This result means the MMPI and CMI was not related to tool which developed based on medical model from etic perspectives, although the tool which had been developed in America Modified to Korean situation. So I dare to say that only the absence of mental illness does not means mental health and the diagnosis of mental illness is not the only criteria of a mental health.

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Current and Future Challenges of Student Assessment in Medical Education from an Outcome-based Education Perspective (성과중심교육 측면에서 우리나라 의과대학 학생평가의 현실과 과제)

  • Park, Jang Hee
    • Korean Medical Education Review
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    • v.15 no.3
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    • pp.112-119
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    • 2013
  • Most medical colleges in Korea have been shifting from traditional education to outcome-based education, which is the general trend in medical education. The purpose of this study was to make some suggestions in light of the reality and challenges of student assessment in medical education from the perspective of outcome- based education. First, those who are responsible for student assessment should be diversified to include faculty, residents, students, and evaluation committee members. They need separate roles in educational evaluation, so evaluation competencies are required for them. Second, various methods for evaluation and score interpretation can be used for effective evaluation. We can adopt diagnostic, formative, and summative evaluation functionally, and the norm-referenced, criterion-referenced, growth-referenced, and ability-referenced evaluation based on criteria for score interpretation. Finally, various evaluation domains and test forms can be administered together in the common lectures in the medical school. We can test not only knowledge but also skills and attitudes, with diverse test forms such as supply and performance types.

Reliability-Based Assessment of Safety and Residual Carrying-Capacity of Steel-Box Pedestrian Bridges (신뢰성에 기초한 강상형 보도육교의 안전도 및 잔존 내하력평가)

  • 조효남;최영민;이은철
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1996.04a
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    • pp.202-211
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    • 1996
  • A number of typical type of steel-box pedestrian bridges are constructed in the metropolitan highway or heavy traffic urban area. Although it has the advantage of speedy construction because of its simple structural form and prefabricated erection method, it has been reported that many of these bridges are deteriorated or damaged and thus are in the state such that it would give unsafe and uncomfortable feeling to pedestrians. In the paper, for the realistic assessment of safety and residual earring-capacity of deteriorated and/or damaged steel box pedestrian bridges, an interactive non-linear limit state model are formulated based on the von Mises' combined stress yield criterion. It is demonstrated that the proposal model is effective for the reliability-based safety assessment and residual carrying-capacity evaluation of steel-box pedestrian bridges. In addition, this study suggests an effective and practical field load test method for pedestrian bridges.

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