• 한국안전학회지
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• 제12권2호
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• pp.17-21
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• 1997

The fatigue crack propagation rate has so far been measured by the effective stress intensity factor range Δ K/sub eff/. But no research has been done to study how much the crack opening ratio influences the expectation of the fatigue crack propagation. Therefore, this paper evaluates of the crack opening ratio on the fatigue crack propagation life by using the method of parameter sensitivity study. Summarizing the result ; ( 1 ) When the crack opening ratio U' is high, the effect of U' gets larger than any other except for the material factor m. But when U' is low, the effect is also diminished. Therefore, the selection of the lowest value possible is desirable in the evaluation of life. (2) When the value of the material factor m is high, the effect of crack opening ratio U' is increased, at the same time the effect of the other parameters also increased wholly. The effect of material factor m itself on life is high, but in case the material factor m is high, that the effect of each parameter on life get higher is unique. In designing, better attention to the material selection should be drawn. (3) In case the stress ratio R gets smaller, the effect of crack opening ratio U' is unchangeable. But the effect of R itself remarkably decreases, and the effect of material factor m somewhat decreases.

• 국제학술발표논문집
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• The 4th International Conference on Construction Engineering and Project Management Organized by the University of New South Wales
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• pp.209-212
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• 2011

Selection of finishing materials in the design stage is an important management factor in terms of use safety and satisfaction, and work cost and process. However, selection of materials in the design stage is usually conducted without related guidelines or a set process, but depends on the experience of the architect or advice of materials company employees. Therefore, the aim of this study was to develop a finishing materials selection process that can be used by a architect. Materials selection related rules collected through interview with experts and five office building cases were used as knowledge. In addition, another aim of the study was to propose a prototype system interface for use in the field.

• Design & Manufacturing
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• 제8권1호
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• pp.27-30
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• 2014

Alloy tool steel such as SKD11 and SKD61 or high speed tool like SKH51 are used as materials for semiconductor dies. Cavities, curl blocks, pot blocks and housings are made from those materials. To make those parts from alloy tool steel or high speed tool, one utilizes discharge machining, and mechanical machining including machining center, milling, drilling, forming grinding and others. In the process of cutting machining and polishing, the die materials become unsuitable for machining owing to bubbles and foreign substances in them, which hinders production process. Therefore, this study focuses on die material selection criteria, and on analysis and comparison of material characteristics to help companies to solve their problems, make die manufacture less burdensome and extend die life.

• 한국지능정보시스템학회:학술대회논문집
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• 한국지능정보시스템학회 2005년도 춘계학술대회
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• pp.302-305
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• 2005

To comply to demand for a development requirement of aircraft design part, the expert system builds up standard knowledge-base based on presently maintained expert knowledge and experience in aircraft structure material selection. It also builds up database based on aircraft design open data, and standard calculation module used for present design and analysis method. This system is developed using Visual Basic language. The expert system standardize aircraft structure material selection and can be applied to all type of elementary stage of aircraft structure design. It is working on Windows, which has a friendly interface and is convenient for debugging, maintenance and transplanting. Explanation of the structure and the function of the system was given in this paper.

• 산업경영시스템학회지
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• 제18권33호
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• pp.45-53
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• 1995

The Purpose of this paper is to describe and demonstrate a quantitative procedure for evaluating alternative material handling systems that are being considered for possible purchase. The procedure considers both quantitative factors(i.e. costs) and qualitative factors(i.e. equipment productivity) that should be considered in the evaluation process. Since these factors are not always quantifiable it is necessary that the procedure be able to quantify all factors in commensurable units. This is accomplished via a modification of the Brown and Gibson model for facility site location and selection. The model was demonstrated via a case example that encompassed the derivation of performance measures for three material handling systems.

• Design & Manufacturing
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• 제13권2호
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• pp.44-48
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• 2019

Motor core products are used as materials for electrical steel sheets and cold-rolled steel sheets according to the performance of motors. The cemented carbide material of the mold punch applied to the motor core material causes many troubles due to abrasion and burr problem. The selection of these materials has a great effect on the production life, mass production, product quality as well as mold life. The cemented carbide applied to the products of the motor core is recognized as a very important part. In this study, cold rolled steel sheet was applied to motor core SCP-1 steel 1.0mm, and The effects of abrasion and punching oil on the shear process were investigated for the selection of cemented carbide. Experiments were conducted to select and apply cemented carbide only for the motor core punch optimized for cold rolled steel. The results showed that the cemented carbide material of $CDK3^{***}$ produced the least wear and burrs.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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• pp.32-33
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• 2014

The appropriate selection of a construction material is important considering the effect on the total project cost and quality. However, the methodologies of the existing systems and databases to suggest search results have been analyzed to lack reliability. Therefore, this study suggests a material searching methodology that results in quantitative results using similarity.

• 한국막학회:학술대회논문집
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• 한국막학회 2002년도 제15회 심포지움
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• pp.115-117
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• 2002

No Abstract, See Full-text

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2003년도 The 8th Asian Symposium on Precision Forging ASPF
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• pp.94-106
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• 2003

In recent years, the production value of Taiwanese mold and die industries have reached to a high peak in 1998, in amount of NT 604 hundred million dollars. But in recent years production value are going down year by year, till year of 2001 the production value have down to NT 394 hundred million dollars. Its main reason might be the major product were following in medium and low price category, the high accuracy and high cost mold and die still rely on import aboard. Therefore how to made the related technical database system on various field to provide the industry user to promote industries competition ability in mold and die is really urgent matter at this moment. In this research, we will offer how to apply the Visual Basic program language to edit a set of more perfect database system of mold and die material selection. At the present time, we have constructed complete Knowledge-Base-System of intelligence for forging mold and die material, the most related data from the existed data, the others are through our additional experimental results. By using this system by the user can got the related and need data easily, we hope it will reduce designing time and cost for mold and die.

• 한국건설관리학회논문집
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• 제9권4호
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• pp.84-91
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• 2008

최근 주택성능등급표시제, 친환경건축물인증제도 등 실내공기질에 관련한 제도가 생겨나고 공동주택 거주자 또한 실내공기 질에 대한 인식을 새롭게 하고 있다. 이러한 시대적 흐름에 발맞추어 최근 신축되거나 리모델링 되는 공동주택에는 친환경 실내마감재료가 적용되고 있다. 하지만, 친환경 실내 마감재료는 일반재료에 비해 그 가격이 고가이며, 분양가 상승을 야기한다. 또한 친환경 마감재료 적용으로 인한 분양가 상승은 거주자로 하여금 경제적 부담을 가중시키게 된다. 따라서 실내 마감공법 별로 적용되는 모든 주재료 및 부 재료에 대해서 친환경성과 경제성을 복합적으로 고려할 필요가 있다. 본 논문에서는 노후 공동주택 리모델링 마감공사 시 환경적인 요인, 경제적인 요인을 복합적으로 고려하여 효율적인 실내 마감재료를 선정하는 방안을 제안하고자 한다.