• Title/Summary/Keyword: Evaluation problem

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A Refined Semi-Analytic Sensitivity Study Based on the Mode Decomposition and Neumann Series Expansion (I) - Static Problem - (강체모드분리와 급수전개를 통한 준해석적 민감도 계산 방법의 개선에 관한 연구(I) - 정적 문제 -)

  • Cho, Maeng-Hyo;Kim, Hyun-Gi
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.27 no.4
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    • pp.585-592
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    • 2003
  • Among various sensitivity evaluation techniques, semi-analytical method(SAM) is quite popular since this method is more advantageous than analytical method(AM) and global finite difference method(FDM). However, SAM reveals severe inaccuracy problem when relatively large rigid body motions are identified fur individual elements. Such errors result from the numerical differentiation of the pseudo load vector calculated by the finite difference scheme. In the present study, an iterative method combined with mode decomposition technique is proposed to compute reliable semi-analytical design sensitivities. The improvement of design sensitivities corresponding to the rigid body mode is evaluated by exact differentiation of the rigid body modes and the error of SAM caused by numerical difference scheme is alleviated by using a Von Neumann series approximation considering the higher order terms for the sensitivity derivatives.

A Refined Semi-Analytic Sensitivity Study Based on the Mode Decomposition and Neumann Series Expansion in Eigenvalue Problem(II) - Eigenvalue Problem - (강체모드분리와 급수전개를 통한 고유치 문제에서의 준해석적 설계 민감도 개선에 관한 연구(II) -동적 문제 -)

  • Kim, Hyun-Gi;Cho, Maeng-Hyo
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.27 no.4
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    • pp.593-600
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    • 2003
  • Structural optimization often requires the evaluation of design sensitivities. The Semi Analytic Method(SAM) fur computing sensitivity is popular in shape optimization because this method has several advantages. But when relatively large rigid body motions are identified for individual elements. the SAM shows severe inaccuracy. In this study, the improvement of design sensitivities corresponding to the rigid body mode is evaluated by exact differentiation of the rigid body modes. Moreover. the error of the SAM caused by numerical difference scheme is alleviated by using a series approximation for the sensitivity derivatives and considering the higher order terms. Finally the present study shows that the refined SAM including the iterative method improves the results of sensitivity analysis in dynamic problems.

Experimental Evaluation of Routing Algorithms for Optimal Load Balancing on SONET Rings with Demand Splitting (분할이 허용된 SONET 링의 루팅 해법들에 대한 비교 분석)

  • 명영수;김후곤
    • Korean Management Science Review
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    • v.18 no.2
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    • pp.107-116
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    • 2001
  • In the ring leading problem with demand splitting, traffic demands are given for each pair of nodes in an undirected ring network and a flow is routed in either of the two directions, clockwise and counter-clockwise. The load of a link is the sum of the flows routed through the link and the objective of the problem is to minimize the maximum link load on the ring. Recently, four different optimal a1gorithms have been developed for solving the problem. In this paper, we compare those algorithms in a single framework and conduct a computational study to evaluate the practical performance of those algorithms.

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A Study on the Multi-Attribute Decision Making based on Eigenvector (Eigenvector를 이용한 다속성의사결정에 관한 연구)

  • 안동규
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.18 no.34
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    • pp.1-8
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    • 1995
  • The practical problem of multi-attribute decision making are formed by the uncertain attribute that the attribute by the alternatives cannot be defined or judged crisphy but only as vague. In this case the final judgements are also represented by vague which have to be ordered to determine the optimal alternative. The problem is more complex if the evaluations of alternatives according to each attribute are expresed vague. This paper described the results of a study done to determine how well multi-attribute decision marking perform in helping a decision maker arrive at a preferred solution to a multi-attribute problem with vague attribute. Particular area of research has concentrated on the issue of combining quantitative and qualitative data supplied by estimation. Futher study considers some method for suitable evaluation of qualitative data.

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Development of a Problem-based Learning Package for RN-BSN Students - Based on the Cases of Women during Pregnancy, Childbirth and Postpartum - (RN-BSN 학생을 위한 문제중심학습(Problem-Based Learning) 패키지 개발 - 임신, 분만, 산욕여성의 상황을 중심으로 -)

  • Song, Young-A;Shin, Hye-Sook
    • Women's Health Nursing
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    • v.11 no.2
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    • pp.99-109
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    • 2005
  • Purpose: The purpose of this study is to present a procedure for developing a PBL package and to provide the example of its application. Method: In this study, the PBL package was proposed based on the integrated curricular under maternity nursing. The PBL package model proposed by Little was applied to this study. Result: The procedure for developing the PBL package includes course objectives, learning objectives, concept mapping, situation scenario, tutor guide, and evaluation method. Clinical scenarios used in 3 PBL packages were composed of a pregnant women, a childbirth women, and a postpartum women. The Eight detailed steps are given in this study. Conclusion: Through these findings, the steps might be easier and more useful for nurse professionals to begin using the PBL package in maternity nursing. In addition, the steps will actively contribute to imply the PBL in nursing education.

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Problem Coping Strategies Depression and the Social Support Needs for Psychological Adjustment of Unemployed Husband's Wives (실직자 가족의 문제와 대처, 우울감 및 심리문제 해결지원요구도 -실직자 아내를 중심으로-)

  • 최규련
    • Journal of Families and Better Life
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    • v.17 no.3
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    • pp.47-62
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    • 1999
  • The purpose of this study was to investigate the problem coping strategies and depression of unemployed husband's wives and to analysis the social support(education and counseling program) needs for their psychological adjustment. The subjects were 139 unemployed husband's wives living in Seoul city and Kyungi-do province. The questionnaire method was used for data gathering. The major findings were as follows" 1) Wives perceived the most negative change of unemployed husband. Wives' depression was influenced by self-esteem evaluation of husband's coping behavior weak health passive coping strategies and negative change of husband and marital relation. 2) Wives needed education and counseling support the most in the area stress & mental health problem marital conflict and marital communication. The result of this study were discussed in the relation with the contents of education and counseling program for unemployed husbands' wives.

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Application of Genetic and Local Optimization Algorithms for Object Clustering Problem with Similarity Coefficients (유사성 계수를 이용한 군집화 문제에서 유전자와 국부 최적화 알고리듬의 적용)

  • Yim, Dong-Soon;Oh, Hyun-Seung
    • Journal of Korean Institute of Industrial Engineers
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    • v.29 no.1
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    • pp.90-99
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    • 2003
  • Object clustering, which makes classification for a set of objects into a number of groups such that objects included in a group have similar characteristic and objects in different groups have dissimilar characteristic each other, has been exploited in diverse area such as information retrieval, data mining, group technology, etc. In this study, an object-clustering problem with similarity coefficients between objects is considered. At first, an evaluation function for the optimization problem is defined. Then, a genetic algorithm and local optimization technique based on heuristic method are proposed and used in order to obtain near optimal solutions. Solutions from the genetic algorithm are improved by local optimization techniques based on object relocation and cluster merging. Throughout extensive experiments, the validity and effectiveness of the proposed algorithms are tested.

Location Analysis for Emergency Medical Service Vehicle in Sub District Area

  • Nanthasamroeng, Natthapong
    • Industrial Engineering and Management Systems
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    • v.11 no.4
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    • pp.339-345
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    • 2012
  • This research aims to formulate a mathematical model and develop an algorithm for solving a location problem in emergency medical service vehicle parking. To find an optimal parking location which has the least risk score or risk priority number calculated from severity, occurrence, detection, and distance from parking location for emergency patients, data were collected from Pratoom sub-district Disaster Prevention and Mitigation Center from October 2010 to April 2011. The criteria of risk evaluation were modified from Automotive Industry Action Group's criteria. An adaptive simulated annealing algorithm with multiple cooling schedules called multi-agent simulated quenching (MASQ) is proposed for solving the problem in two schemes of algorithms including dual agent and triple agent quenching. The result showed that the solution obtained from both scheme of MASQ was better than the traditional solution. The best locations obtained from MASQ-dual agent quenching scheme was nodes #5 and #133. The risk score was reduced 61% from 6,022 to 2,371 points.

Development and evaluation of a pediatric nursing competency-building program for nursing students in South Korea: a quasi-experimental study

  • Koo, Hyun Young;Lee, Bo Ryeong
    • Child Health Nursing Research
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    • v.28 no.3
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    • pp.167-175
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    • 2022
  • Purpose: The present study aimed to develop and examine the effectiveness of a pediatric nursing competency-building program for nursing students. Methods: This was a quasi-experimental study with a nonequivalent control group pretest-posttest design conducted between October and December 2021. The participants included 40 nursing students (20 each in the experimental and control groups) at a university in a South Korean city. The pediatric nursing competency-building program integrated problem-based learning and simulation into clinical field practice. The experimental group participated in the program, while the control group did not. Data were analyzed using the 𝑥2 test, the independent t-test, and repeated-measures analysis of variance. Results: Pediatric nursing competency and clinical performance showed a greater increase in the experimental group than in the control group. However, the change in problem-solving ability in the experimental group was not significantly different from that in the control group. Conclusion: The pediatric nursing competency-building program effectively improved students' pediatric nursing competency and clinical performance.

A Case Study on Vocal Aerobic Treatment Voice Therapy Development and Application for Classical Singers (성악가를 위한 VAT 음성치료 개발 및 적용 사례연구)

  • Yoo, Jae-Yeon;Lee, Ha-Na
    • 재활복지
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    • v.22 no.1
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    • pp.157-168
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    • 2018
  • The purpose of this study is to investigate the impact of semi-closed vocal training-based Vocal Aerobic Treatment on the voice improvement of soprano. Study subject was one soprano who appealed to the suffering of her voice problem due to vocal cord nodule. A study method of conducting pre/post acoustic evaluation and subjective voice evaluation to compare the measures was used; Vocal Aerobic Treatment was carried out twice a week for a total of 32 session. In the acoustic evaluation, MDVP (multi-dimensional voice program) and VRP (voice range profile) were used to evaluate the pitch, voice quality, and voice range; in the subjective voice evaluation, SVHI (singing voice handicap index) was used to assess voice satisfaction. As a result of the pitch evaluation, the soprano maintained a proper Fo. As a result of the voice quality evaluation, the jitter, shimmer, and the noise harmonic ratio numbers decreased compared to the numbers shown before the treatment. As a result of the voice range evaluation, the scope of the range was broadened, with the number of semitone increasing from 30 to 35. As for the subjective voice evaluation, the result of the total score obtained after the survey report divided by the number of questions showed a decrease from 3.6 to 0.6. The soprano herself reported of having a minor extent of a voice problem. The summary of the above results reflects that Vocal Aerobic Treatment is useful in the voice improvement of vocalists However, as this study is case research regarding the Vocal Aerobic Treatment effect on one soprano, further research on the treatment effect covering many other vocalists is necessary. Also, there is a need for follow-up studies regarding voice management and voice treatment program on not only the vocalists but also the voice users in many other professions.