• Title/Summary/Keyword: effective evaluation

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Development of an analytic algorithm for reach prediction (동작한계 예측을 위한 해석적 알고리즘의 개발)

  • 정의승;정민근;기도형
    • Journal of the Ergonomics Society of Korea
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    • v.12 no.1
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    • pp.17-24
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    • 1993
  • Today, rapid development and timeliness of introducing a new product be- comes a more influencing factor of determing its competitive power due to a shortened product cycle, while rapid improvement of manufacturing technology makes product design and manufacturing fuse together. This implies that prod- uct usability evaluation and improvement starts right from its design phase, resulting in less development time and cost. To make this possible, proper as- sessment of human reach is one of essential functions for ergonomic product us- ability evaluation, specifically in the platform of computer-aided ergonomic evaluation models or any CAD system with a built-in man model. In this study, an analytic reach prediction algorithm ensuring the posture that human naturally takes, is presented by employing the methods developed for robot kinematics. Among robot kinematic methods for solving the multi-link system, the resolved motion method was found to be effective to solve human reach as a redundant manipulator model. Also, the joint range availability was used as a performance fonction to guarantee human naturalness. The result is expected to be directly applicable to product usability evaluations.

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Analysis of Characteristic Evaluation of Microdrilling for the Cemented Carbides Materials (초경합금 소재 마이크로드릴의 가공특성 평가)

  • 김건회
    • Transactions of the Korean Society of Machine Tool Engineers
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    • v.11 no.6
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    • pp.52-59
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    • 2002
  • Resently, reduction of industrial products in size and weight has increased by the application of micro-drill for gadgets of high precision and gave rise to a great interest in a micro-drilling. Due to the lack of tool stiffness and the chip packing, micro-drilling requires not only the robust tool structure which has not affected by the vibration, but also the effective drilling methods designed to prevent tool fracture from cutting troubles. Firstly, this paper presents a optimum characteristic evaluation method of 0.15mm microdrill in consideration of new manufacturing processes for improving the product rate and extend the tool life, and secondly suggest between microdrilling characteristic properties of tool md evaluation of workpiece quality through experiment.

Study on Highly Accuracy Quality Evaluation of Spot Weld by use of Image Processing Technique

    • Journal of the Korean Society of Manufacturing Technology Engineers
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    • v.5 no.4
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    • pp.38-46
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    • 1996
  • This paper discusses the feasibility of Ultrasonic Nondestructive Evaluation (UNDE) technique for sport weld quality. Ultrasonic c-scan image assisted by image processing technique was used for Nondestructive Evaluation(NDE) of spot weld quality. Ultrasonic testing results obtained were confirmed and compared by Optical Microscope and SAM(Scanning Acoustic Mircroscope) observation of the spot-weld cross section, The results show that the nugget dinameter can be successfully measured with the accuracy of 0.5mm. It was ascertained that ultrasonic c-scan technique is very effective method for the sake of the approach to the quantitative measurement of nugget diameter and the discrimination of the corona bond from nugget. Additional support for the above conclusions is provided by the results for galvanized steel. The ultrasonic results for galvanized welds generally correspond to the results for uncoated steel. Finally, it was found that the above-mentioned technique can be sufficiently applied to NDE method for securing the Quality Assurance(QA) of spot welded products in production line.

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An Effective Fuzzy Multi-Criteria Decision Making Methodology in the Intersectional Dependence Relations (교차종속관계하에서의 효율적인 퍼지 다기준의사결정법)

  • 심재홍;김정자
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.21 no.45
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    • pp.11-23
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    • 1998
  • This paper presents a more efficient evaluation of alternatives by use of multi-criteria decision making methodlogy under fuzzy intersectional dependence relations. The performance evaluation of most systems such as weapons, enterprise systems etc. are multiple criteria decision making problems. The descriptions and judgements on these systems are usually linguistic and fuzzy. The traditional methods of Analytic Hierarchy Process(AHP) are mainly used in crisp(non-fuzzy) decision applications with a very unbalanced scale of judgements and rank reversal. To overcome these problems, we will propose a new, general decision making method for evaluation models using fuzzy AHP(FAHP) under fuzzy intersectional dependence relations. The T.M.S alternatives A, B and C will be evaluted by the Fuzzy Analytic Hierachy Process (FAHP) based on entropy weight in this study. We will use symmetric triangular fuzzy numbers to indicate the relative strength of the elements in the hierachy and degree of intersection between criteria. These problems are evaluated by five criteria : tactical criteria, technology criteria, maintenance criteria, economy criteria, advacement criteria.

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Deterioration Evaluation of Railway Line Segments Using Analytic Hierarchy Process (AHP를 활용한 철도선로구간 노후도 평가)

  • Kim, Seong-Ho
    • Journal of the Korean Society for Railway
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    • v.14 no.6
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    • pp.569-574
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    • 2011
  • An effective approach to distributing budget to railway line facility improvement is to use investment priorities of railway line segments based on their deterioration. In this paper we present an evaluation method of railway line segment deterioration which can be used to distribute limited budget. Railway line facilities include rail track, railroad switch, subgrade, bridge, tunnel. These facilities and line shape can affect line segment deterioration. Deterioration evaluation method we present is a weighted sum of each component deterioration scores. The component weight can be obtained from experts using analytic hierarchy process.

Development and Application of Online Health Promotion Education for University Students (대학생을 위한 건강증진 가상강좌 개발 및 적용)

  • Jang, Hee-Jung
    • Journal of Korean Academy of Nursing Administration
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    • v.15 no.2
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    • pp.255-263
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    • 2009
  • Purpose: The purpose of this study was to develop online health promotion an education program for university students and to evaluate its changes. Method: An online health promotion education program was established through analysis, designing, development, implementation and evaluation stages. This was a quasi-experimental, one group pretest-posttest design. The subjects of this study were 97 students in one university, and they were provided the online class for 16 weeks. Data was analyzed by descriptive statistics and paired t-test. Result: The results of program evaluation were positive, which included instruction function 3.94, system construction 4.14, system function 3.90, and overall evaluation 4.03 on the scale of 5. The posttest scores of health promoting lifestyle(t=-2.316, p=0.024) was significantly higher than those of the pretest. Conclusion: This study shows that the online health promotion education program was an effective educational method to improve health promotion lifestyle for the university students.

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Structural Behavior Characteristics Evaluation of Shear Wall Outrigger System Subject to Horizontal Loads (수평하중을 받는 전단벽 아웃리거 시스템의 거동특성 평가)

  • Kim, Ho-Soo;Lee, Han-Joo;Hong, Seok-Il;Lim, Young-Do
    • Proceeding of KASS Symposium
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    • 2006.05a
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    • pp.110-117
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    • 2006
  • This study presents an effective stiffness-based optimal technique to consider floor rigid diaphragm action and a technique to evaluate the structural behavior characteristics and efficiency for tall shear wall outrigger system subject to horizontal loads. To this end, isoparametric plane stress element with rotational stiffness is used for shear wall element and stiffness gradient is calculated. Also, the approximation concept to solve effectively the large scaled problems, member grouping technique and resizing technique are considered. To verify the effectiveness and usefulness of this technique, the efficient evaluation method for three types of 50 story model with core and outrigger system is presented.

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SAFETY EVALUATION OF ROCK-FILL DAM

  • HoWoongShon;YoungChulOh;YoungKyuLee
    • Journal of the Korean Geophysical Society
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    • v.6 no.2
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    • pp.89-97
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    • 2003
  • For safety evaluation of a rockfill dam, it is often necessary to investigate spatial distribution and dynamic characterization of weak zones such as fractures. For this purpose, both seismic and electric methods are adopted together in this research. The former employs the multichannel analysis of surface waves (MASW) method, and aims at the mapping of 2-D shear-wave velocity (Vs) profile along the dam axis that can be associated with dynamic properties of filled materials. The latter is carried out by DC- resistivity survey with a main purpose of mapping of spatial variations of physical properties of dam materials. Results from both methods are compared in their signature of anomalous zones. In addition, downhole seismic survey was carried out at three points within the seismic survey lines and results by downhole seismic survey are compared with the MASW results. We conclude that the MASW is an efficient method for dynamic characterization of dam-filling materials, and also that joint analyses of these two seemingly unrelated methods can lead to an effective safety evaluation of rock-fill dam.

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Productivity Enhancement of Automotive Glass Manufacturing Company by the Improvement of Working Environment (작업환경 개선을 통한 자동차 유리제조업체의 생산성 향상)

  • Yang Sung Hwan;Cho Mun Son;Park Peom
    • Journal of the Korea Safety Management & Science
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    • v.7 no.2
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    • pp.85-94
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    • 2005
  • The purpose of this study is to execute the investigation of injurious factors causing muscle-skeletal diseases at an automotive glass manufacturing company and, on the basis of the results, to enhance productivity by the improvement of working environment. By using an survey and an ergonomic evaluation method, symptoms of muscle-skeletal diseases of workers and working postures at each process were analyzed, and quantitative evaluation of muscle-skeletal disease risk against each process was performed. Based on the result of the evaluation, to enhance the working environment, improvement of worktable, working space, tools, and outfit was suggested, and induction of mechanical system was also suggested. Suggested improvement plan was applied to the workplace step by step and it is confirmed that improvement plan not only removes the injurious factors of muscle-skeletal diseases but also is effective to enhance productivity.

A Study on the Evaluation of Durability of Fiber Reinforced Concrete According to the Change of External Conditions (외부조건의 변화에 따른 섬유보강콘크리트의 내구성능 정가에 관한 연구)

  • Kim, Nam-Wook
    • Journal of the Korean Society of Safety
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    • v.23 no.5
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    • pp.97-104
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    • 2008
  • This study was intended to evaluate the permeable performance through a change of reinforcing materials, curing condition, durability evaluation and permeability test, and to select the reinforcing material which could reduce the durability and water tightness from it, as the study for considering how the change of the outside's environment factors that the concrete structure actually contacted with impacted the concrete's durability especially the permeability by referring to such the background of the study. Accordingly, it was judged that evaluating the permeability by considering the severe environment condition where the concrete structure was placed in was more reasonable than measuring the existing permeability coefficient conducted in the sound state for the permeability evaluation of actually-used concrete structure. In this study, it also could be known that the specimen of hybrid fiber reinforced concrete which mixed the long and short steel fiber was the most effective for water tightness enhancement in severe environmental conditions.