• Title/Summary/Keyword: problem evaluation

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Evaluation for Space Distribution of Dust Cloud in Hybrid Mixtures (이상계 혼합기에서의 분진운의 공간분포에 대한 평가)

  • 한우섭;정국삼
    • Journal of the Korean Society of Safety
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    • v.10 no.1
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    • pp.35-40
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    • 1995
  • This study dealed with problem to estimate the uniformity of dust clouds, as a fundamental study to estimate the ignition hazardous evaluation of hybrid mixtures. The developed method was proposed to grasp space distribution of dusts, and also, an experimental apparatus considering with dispersion and reproduction of dusts were uniquely devised and studied.

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Mixed-Model Sequencing Using Genetic Algorithms with Multiple Evaluation Criteria (다목적 유전 알고리듬을 이용한 혼합모델 조립라인의 최적 생산순서계획)

  • Kim, Yearn-Min;Kim, Young-Jin
    • IE interfaces
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    • v.13 no.2
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    • pp.204-210
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    • 2000
  • This paper deals with the problem of mixed-model sequencing on an assembly line. In this sequencing problem we want to minimize the risk of the conveyor stoppage and the total utility work. This paper applies genetic algorithm to solve the mixed-model sequencing problem which is formulated as an integer programming. The solution we get from this algorithm is compared with the solution of Tsai(1995)'s.

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PERTURBATION ANALYSIS OF DEFLATION TECHNIQUE FOR SYMMETRIC EIGENVALUE PROBLEM

  • JANG, HO-JONG
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.5 no.2
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    • pp.17-23
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    • 2001
  • The evaluation of a few of the smallest eigenpairs of large symmetric eigenvalue problem is of great interest in many physical and engineering applications. A deflation-preconditioned conjugate gradient(PCG) scheme for a such problem has been shown to be very efficient. In the present paper we provide the numerical stability of a deflation-PCG with partial shifts.

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On the Fuzzy Approach to Integrated Evaluation of Complex Systems (퍼지 평가의 통합특성에 관하여)

  • 이철영;임봉택
    • Journal of Korean Port Research
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    • v.13 no.1
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    • pp.79-86
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    • 1999
  • This paper deals with the evaluation problem of complex systems by introducing a fuzzy approach. The authors are functionally supposing a hierarchical structure model of a complex system and give light on the following problems. First for the purpose of clarifying the characteristics of measures the property and differences between two method such as linear and fuzzy viewpoint are discussed through two level-down evaluation process. Second the integrated evaluation process which keeps reversibility between hierarchical levels is discussed and obtained some necessary conditions for reversibility of fuzzy evaluation. From these results it is expected that the fuzzy approach overcomes partly the limitation of reductionism at the hierarchical evaluation of complex systems.

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A Survey on Ergonomic Evaluation Methods of Agricultural Work for Preventing WMSDs

  • Kim, Yu-Chang
    • Journal of the Ergonomics Society of Korea
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    • v.30 no.4
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    • pp.465-472
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    • 2011
  • Objective: The aim of this paper is to introduce ergonomic evaluation methods for agricultural work. Background: Work-related Musculoskeletal Disorders(WMSDs) became a major problem in agriculture industry recently. A number of ergonomics evaluation methods have been developed in order to evaluate the work load for preventing WMSDs. The workload evaluation methods were developed for manufacturing industry. Therefore, these ergonomic evaluation methods were used carefully in agriculture industry because work type in agriculture different from work type in manufacturing. Method: Various references of ergonomic evaluation methods such as OWAS, REBA, RULA, NLE and Snook table have been reviewed for agricultural work. Results: This paper presents the characteristics, the selection and application procedure of ergonomic evaluation methods for agricultural work. Application: These results can be used to provide baseline information for ergonomic evaluation methods.

A Study on Evaluation in College Mathematics Education in the New Normal Era (뉴노멀(New Normal) 시대 대학수학교육에서의 과정중심 PBL 평가 - '인공지능을 위한 기초수학' 강좌 사례를 중심으로 -)

  • Lee, Sang-Gu;Ham, Yoonmee;Lee, Jae Hwa
    • Communications of Mathematical Education
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    • v.34 no.4
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    • pp.421-437
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    • 2020
  • Problem/Project based learning(PBL) is a student-centered teaching method in which students collaboratively solve problems and reflect their experiences. According to the results of PBL study and the experiences of the authors in PBL instruction, this paper introduced the necessities, output and significance of learning process PBL evaluation method and sums up our PBL evaluation process. The issue of appropriate and fair evaluation has been raised in untact (non-contact) university mathematics education due to the novel coronavirus (COVID-19) of the year 2020. To this end, when we had the course on for the summer semester held at S University in the summer of 2020. To ensure the fairness in evaluation and to improve the quality of our college math education, the PBL evaluation method was fully adapted. As a result, most of the students who took the lecture have learned a wide range of related knowledge without a single exception, and students agreed it is an ideal, fair, rational, and effective evaluation method applicable to other online courses in the era of untact education. This case was summarized in detail and introduced in this paper.

A Study on Purge Gas Inflow according to Valve Operation Sequence during Staged Combustion Cycle Engine Reignition Test (다단연소 사이클 엔진 재점화 시험 시 밸브 작동순서에 따른 퍼지가스 유입에 대한 연구)

  • Hwang, Changhwan;Lee, Jungho;Kim, Chaehyeong;Jeon, Jun-Su;Park, Jae-Young;Lee, Kwang-Jin;Cho, Nam-Kyung;Kim, SeungHan;Han, Yeoungmin
    • Journal of the Korean Society of Propulsion Engineers
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    • v.26 no.4
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    • pp.64-71
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    • 2022
  • For the development of an improved upper-stage engine, research on a staged combustion cycle liquid rocket engine is in progress. A cold flow test, ignition test, and combustion test plans were established and performed to develop reignition combustion technology. In order to solve the problem of purge gas flowing into the fuel line, which may cause cavitation in the turbo pump during reignition, the test results of each stage were analyzed. Based on the analysis results, the purge gas inflow problem was solved by reducing the overlapping time between the operation of the bubble removal valve and the opening of the purge valve and the engine fuel valve. Based on this, the reignition combustion test was successfully performed.

A Study on the Results of Use of Open-ended Problems for Evaluation in Elementary Mathematics (초등 수학 평가를 위한 개방형 문제의 활용 결과 분석)

  • Lee, Dae-Hyun
    • The Mathematical Education
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    • v.47 no.4
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    • pp.421-436
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    • 2008
  • Mathematics assessment doesn't mean examining in the traditional sense of written examination. Mathematics assessment has to give the various information of grade and development of students as well as teaching of teachers. To achieve this purpose of assessment, we have to search the methods of assessment. This paper is aimed to develop the open-ended problems that are the alternative to traditional test, apply them to classroom and analyze the result of assessment. 4-types open-ended problems are developed by criteria of development. It is open process problem, open result problem, problem posing problem, open decision problem. 6 grade elementary students who are picked in 2 schools participated in assessment using open-ended problems. Scoring depends on the fluency, flexibility, originality The result are as follows; The rate of fluency is 2.14, The rate of flexibility is 1.30, and The rate of originality is 0.11 Furthermore, the rate of originality is very low. Problem posing problem is the highest in the flexibility and open result problem is the highest in the flexibility. Between general mathematical problem solving ability and fluency, flexibility have the positive correlation. And Pearson correlational coefficient of between general mathematical problem solving ability and fluency is 0.437 and that of between general mathematical problem solving ability and flexibility is 0.573. So I conclude that open ended problems are useful and effective in mathematics assessment.

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Development of an Instructional Design Model for Practical Problem-Based Learning in Practical Arts Based on the Backward Design Model (백워드 설계 모형에 기초한 실과 실천적 문제 중심 수업 설계 모형 개발)

  • Lee, Eun-young;Choi, Ji-Yeon;Chae, Jung-Hyun
    • Journal of Korean Home Economics Education Association
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    • v.31 no.2
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    • pp.155-175
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    • 2019
  • This study aimed to present a concrete and systematic lesson design model for practical problem-based learning in Practical Arts based on the backward design model. To this purpose, this study was conducted in the following four stages: analysis, design, development, and evaluation. In the analysis stage, the literature related to the practical-problem-based curriculum and the instructional design model were reviewed as the theoretical foundations, and the 2015 revision of Practical Arts curriculum was analyzed. In the design stage, based on the literature review, the stages and sub-elements of practical-problem-based learning in Practical Arts were determined, and a template of instructional design was constructed. In the development stage, the design model was drafted based on the stages and sub-elements determined at the design stage. In the evaluation stage, the drafted design model from the development stage was evaluated, modified, and enhanced through expert verification. Based on the suggestions from the experts, the 'practical problem setting' stage was added to the original three-stage model, resulting in a model composed of the following four stages: practical problem setting, goal setting, evaluation planning, and learning activity planning. The experts appraised that the developed model of practical-problem-based instructional design in Practical Arts to be a systematic template that would serve as a concrete guideline for teachers who are trying to design classes based on practical problems.

The effectiveness of Advertising with Negrative Appeal -concentrating on magazine apparel ads taking social problems as their themes- (부정적 소구 광고의 효과 -사회문제를 주제로 한 잡지 의류광고를 중심으로-)

  • 변상은;김인숙
    • Journal of the Korean Society of Clothing and Textiles
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    • v.23 no.7
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    • pp.953-964
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    • 1999
  • The purpose of this study was to analyze the effectiveness of negative appeal ads taking social problems as their themes. Two social problem ad themes concerning abortion and drug addiction were selected as stimulus. Questionnaires consisted of questions about affective response cognitive evaluation consumer's characteristics(sex, clothing involvement social problem involvement) and the ad and brand attitudes They were distributed to 200 high school students in Seoul. Results were : 1 The affective response consisted of 4 dimensions(negative inactivating activating positive) and the cognitive evaluation had 3 dimensions(utility·persuasive power creativity awareness) 2. Creativity and awareness dimensions and the ad attitude had positive influence on the brand attitude for the abortion theme ad,. Creativity dimension and consumer's clothing involvement had positive influence on the brand attitude for the drug addiction theme ad . Especially the affective response had no significant influence on the brand attitude. This result suggests that in case of negative appeal ads the affective response does not necessarily degrade the brand attitude while positive cognitive evaluation on creativity and awareness of the could influence the brand attitude favorably through raising attention to the brand resulting in high effectiveness of the ad.

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