• Structural Engineering and Mechanics
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• v.20 no.2
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• pp.241-257
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• 2005

A numerical approach combining the finite element method with two different stability criteria namely the Budiansky and the phase-plane buckling criteria is used to study the dynamic buckling phenomena of plate and shell structures subjected to sudden applied loading. In the finite element analysis an explicit time integration scheme is used and the two criteria are implemented in the Finite Element analysis. The dynamic responses of the plate and shell structures have been investigated for different values of the plate and shell imperfection factors. The results indicate that the dynamic buckling time, which is normally considered in predicting elasto-plastic buckling behavior, should be taken into consideration with the buckling criteria for elastic buckling analysis of plate and shell structures. By selecting proper control variables and incorporating them with two dynamic buckling criteria, the unique dynamic buckling load can be obtained and the problems of ambiguity and contradiction of dynamic buckling load of plate and shell structure can be resolved.

• Journal of the Korean Society of Safety
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• v.16 no.3
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• pp.53-60
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• 2001

This paper presents a graphical method for hazard assessment of electric shock by safety criteria. For the human body to be safety actual body current should not exceed safety criteria, i.e. allowable body current. The assessment method presented in this paper is based m the safety criteria of the IEEE Standard 80 as well as the IEC 479-1. The hazard can be assessed in terms of alterable touch voltages instead of alterable body current. Thus, the hazard assessment of given electric shock condition is referred to a procedure by which the actual touch voltages are compared with the allowable (safe) touch voltages. Since the IEC 479-1 safety criteria are nonlinear, the graphical method is presented for the hazard assessment. Body current and body voltage are calculated with the allowable touch voltage. A comparison of the safety criteria of two widely accepted standards, i.e. the IEEE Std 80 End the IEC 479-1 is proposed. Also Thevenin equivalent resistance is obtained from electric shock model expressed by two-port earth-grid-foot system. On the basis of calculated results, the allowable touch voltage, the body current and the body voltage we can conduct the hazard or safety assessment and estimate the severity of electric shock.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.20 no.2
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• pp.183-196
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• 2009

The purpose of this study is to develop school library evaluation criteria by individual provincial office of education. Data was collected from several school library evaluation criteria. Based upon the data new evaluation criteria were developed in order to increase student academic achievement and apply various school environment. Evaluation items were divided into three items: library programs, school support, service. Evaluation methods were identified into survey method, statistics method, and applied standard statistics method. From three methods, applied standard statistics method was selected. This method included quantitative items and qualitative items. Quantitative items have two criteria from budget, three criteria from collection, and three criteria from use. Qualitative items have two criteria: collection and book usage.

• KIEAE Journal
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• v.15 no.6
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• pp.87-92
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• 2015

Purpose: The green building certification system in Korea was introduced in 2002 and developed as an improvement version of the G-SEED(Green Standard for Energy and Environmental Design) system in 2013. This study conducts surveys targeting architectural designers and users on significance of certification assessment criteria for apartment buildings on the G-SEED system and examines the differential views between the two groups on assessment criteria. Method: First, The AHP(Analytic Hierarchy Process) method was used to find importance of assessment criteria and then the importances were compared with weighted points on the certification standard. Second, the t-test was used to investigate differential views between designer and user groups on certification assessment criteria based on drawn importances. Result: (1) While designer group considered land use and transportation, energy and environmental pollution, and water circulation management as more important, user group did material and resource, maintenance management, ecological environment, and indoor environment as more important. (2) Based on t-test results, sustainable energy, water circulation system, site management, habitat, acoustical environment, and light environment were found to be different on importance between the two groups.

• The Korean Journal of Pain
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• v.25 no.3
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• pp.173-182
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• 2012

Background: Fibromyalgia (FM) is characterized by chronic widespread pain with a low pain threshold. The aim of this study was to compare two criteria for the diagnosis and assessment of FM and to analyze the correlation and agreement between the 1990 and 2010 American College of Rheumatology (ACR) preliminary diagnostic criteria for FM. Methods: We studied 98 patients who had already been diagnosed as having FM using the 1990 criteria or 2010 preliminary criteria. Tender point examination, FM impact questionnaire (FIQ) and pain visual analog scale (VAS) were obtained. According to the preliminary criteria, FM was quantified as WPI (widespread pain index) and the SS scale (symptom severity) and the two criteria were compared. Results: Among 98 patients, 78.6% of the patients were diagnosed with the 1990 ACR criteria and 93.9% of the patients were diagnosed with the ACR preliminary diagnostic criteria, and there was also significant agreement between the two criteria (P < 0.01). There was a correlation with the WPI and the tender point, with the SS and the FIQ, and with the sum of the WPI and SS and the FIQ. Conclusions: The ACR preliminary diagnostic criteria for FM were in agreement with the 1990 ACR criteria during the disease course. The preliminary criteria were the more sensitive method than the 1990 criteria. In addition, the 2010 criteria might have advantages since it is easy to assess the physical and psychological symptoms and can be quantified. Therefore, the ACR preliminary diagnostic criteria for FM could be used more conveniently for clinical diagnosis and follow up evaluation after starting management of FM.

• Structural Engineering and Mechanics
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• v.35 no.1
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• pp.19-35
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• 2010

This paper proposes a hybrid heuristic and criteria-based method of optimum design which combines the advantages of both the iterated simulated annealing (SA) algorithm and the rigorously derived optimality criteria (OC) for structural optimum design of reinforced concrete (RC) buildings under multi-load cases based on the current Chinese design codes. The entire optimum design procedure is divided into two parts: strength optimum design and stiffness optimum design. A modified SA with the strategy of adaptive feasible region is proposed to perform the discrete optimization of RC frame structures under the strength constraints. The optimum stiffness design is conducted using OC method with the optimum results of strength optimum design as the lower bounds of member size. The proposed method is integrated into the commercial software packages for building structural design, SATWE, and for finite element analysis, ANSYS, for practical applications. Finally, two practical frame-shear-wall structures (15-story and 30-story) are optimized to illustrate the effectiveness and practicality of the proposed optimum design method.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.6
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• pp.930-937
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• 2003

The extension of design life among power plants is increasingly becoming a world-wide trend. Kori #1 unit in Korea is operating two cycle. It has two man-ways for tube inspection in a steam generator which is one of the important components in a nuclear power plant. Especially, stud bolts fur man-way cover have damaged by disassembly and assembly several times and degradation for bolt materials for long term operation. It should be evaluated and compared by ASME Code criteria for integrity evaluation. Integrity evaluation criteria which has been made by the manufacturer is not applied on the stud bolts of nuclear pressure vessels directly because it is controlled by the yield stress of ASME Code. It can apply evaluation criteria through FEM analysis to damaged female threads and to evaluated safety fer helical-coil method which is used according to Code Case-N-496-1. From analysis results, we found .that it is the same results between stress intensity which got from FEM analysis on damaged female threads over 10％ by manufacture integrity criteria and 2／3 yield strength criteria on ASME Code. It was also confirmed that the helical-coil repair method would be safe.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.12
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• pp.2284-2291
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• 2010

In this paper, improved stability criteria for linear systems with time-varying delays are proposed. By constructing a new Lyapunov functional, novel stability criteria are established in terms of linear matrix inequalities (LMIs). Two numerical examples are carried out to support the effectiveness of the proposed method.

• English Language & Literature Teaching
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• v.17 no.1
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• pp.191-208
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• 2011

The quantitative study investigated perceptions of evaluative criteria in L2 writing between two groups - learners (N=212) and instructors (N=52) in Korea. Specifically, the purpose of the study is (1) to examine learners' and instructors' perceptions on evaluative criteria in L2 writing and to provide empirical evidence concerning how they respond to a list of them and (2) to ultimately devise appropriate rating criteria applicable to an EFL context like Korea. Analyses of evaluative criteria were conducted using factor analysis and yielded the following results: learner and instructor groups perceived the evaluative criteria differently and weighted them in a different way. For the learner group, the combined elements of grammar and language in use were identified as Factor 1 and mechanics as Factor 2. The results may infer that learners' response patterns are primarily linked to their instructors' writing practice in class, which may largely focus on grammatical knowledge based on lexical use and mechanical accuracy. Similarly, the instructor group acknowledged grammatical knowledge as Factor 1 and lexical use as Factor 2. The first two factors found in both learner and instructor groups indicate that in an EFL context like Korea, the form-then-content way of teaching and learning is still being considered more effective in L2 writing than any other method. Taking into consideration these perceptive similarities and differences between learners and instructors, the categories of evaluative criteria in writing include content and organization, grammar, mechanics, language in use, and flow of the essay, respectively.

• Korean Management Science Review
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• v.18 no.2
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• pp.73-85
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• 2001

Recently increasing amount of efforts has been devoted to the improvement of logistics in the marine products industry. Yet, few studios have been conducted on the development of site selection models of marine products centers. This paper Proposes a systematic assessment model for the decision making, which is composed of a set of evaluation criteria and an appropriate evaluation method. In choosing criteria we consider completeness and comprehensiveness to reach a right solution. For more flexibility of the model in the future, this study proposes two sets of criteria according to the size of planned centers. The Analytic Hierarchy Process (AHP) is adopted in this study, since the criteria incorporate both subjective factors and objective factors and the AHP is known effective in the situation. This study then illustrates the model application with plausible alternatives. Finally, a dependency problem in the decision criteria is discussed and the Analytic Network Process (ANP) is recommended, in the context, as e solution method.