• Steel and Composite Structures
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• 제10권4호
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• pp.331-348
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• 2010

Ample research effort has been oriented into developing damage indices with the aim of estimating in a reasonable manner the consequences, in terms of structural damage and deterioration, of severe plastic cycling. Although several studies have been devoted to calibrate damage indices for steel and reinforced concrete members; currently, there is a challenge to study and calibrate the use of such indices for the practical evaluation of complex structures. The aim of this paper is to introduce an energy-based damage index for multi-degree-of-freedom steel buildings that accounts explicitly for the effects of cumulative plastic deformation demands. The model has been developed by complementing the results obtained from experimental testing of steel members with those derived from analytical studies regarding the distribution of plastic demands on several steel frames designed according to the Mexico City Building Code. It is concluded that the approach discussed herein is a promising tool for practical structural evaluation of framed structures subjected to large energy demands.

• 한국컴퓨터정보학회논문지
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• 제23권11호
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• pp.123-128
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• 2018

When the injection molding system molds some plastic products, defective product rate will be increased if plastic materials have some excessive moisture content. Therefore, it is very important to control the dehumidification and drying of plastic material. Since the moisture content of the plastic material may change from time to time depending on the material and the molding process, it is necessary to observe the change in real time and maintain a constant moisture content. To solve these problems, I proposed a smart factory system model for plastic molding in this paper. In addition, I designed the interface module to be installed in the dehumidifying dryer which is the core of this process. In addition to this, performance tests were conducted to check the effectiveness and the results were verified as valid.

• 농촌계획
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• 제25권3호
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• pp.11-18
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• 2019

It is widely known that agricultural plastic waste incineration by farmers may cause big forest fire or fine dust in rural areas. Hence, how to increase the rate of collection and recycling of the agricultural plastic waste is of concern to policy makers especially for rural environment. The purpose of this study is to find the determinants of the collection rate of agricultural plastic waste. This study used the data from 'Research on Agricultural Waste' by the Korea Environment Corporation from year 2012 to 2015 for 163 regions. This study found that the compensation rate for collection, the frequency of collecting services, and the quality of waste are important to increase the collection rate. And the regions with more elderly and low income people are more likely to have higher collection rate. Finally, the chief producing regions that are specialized in a certain crop shows higher collection rate.

• 대한두개안면성형외과학회지
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• 제23권1호
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• pp.34-38
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• 2022

Severe temporal hollowing deformities can occur in patients who undergo craniectomy after intracranial hemorrhage. Reconstruction surgery for cosmetic purposes using silicone implants in patients with temporal hollowing deformities after craniectomy is advantageous because the procedure is simple and rapid, with a short recovery time, resulting in lower overall treatment costs. Of paramount importance, this option yields highly satisfactory results for patients. The authors present three cases of simple and fast surgery using silicone implants where highly satisfactory outcomes were obtained.

• 콘크리트학회논문집
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• 제22권6호
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• pp.825-832
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• 2010

철근콘크리트 구조물은 위험 단면이 휨강도에 도달하더라도 이 단면에서 소성힌지가 형성되어 휨모멘트가 재분배되어 곧바로 파괴에 도달하지 않는다. 이러한 소성힌지 영역에서 발생하는 비탄성 변형에 의해 소성 회전이 발생한다. 소성힌지길이는 주로 재료 특성에 영향을 받는다. 이 연구에서는 유로코드2에서 제시하고 있는 재료 모델로부터 산정된 휨곡률 분포로부터 소성힌지길이와 소성회전각을 일관되게 산정하였다. 재료 모델의 한계값 즉, 콘크리트 극한변형률, 철근 극한변형률 및 철근의 경화비(k)가 소성회전능력에 미치는 영향을 분석하였다. 해석 결과 콘크리트 극한변형률 및 철근 극한변형률이 증가함에 따라 소성회전능력이 증가하였고 특히, 철근의 경화비(k)가 증가함에 따라 소성 회전각은 크게 증가되는 것으로 나타났다. 따라서 각 재료 모델의 한계값 결정에 세심한 주의가 필요할 것으로 나타났다.

• 소성∙가공
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• 제17권7호
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• pp.517-522
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• 2008

A visco-plastic self-consistent (VPSC) polycrystal model has been applied to simulate texture simulation and anisotropic properties of DP steels during deep drawing process. In order to evaluate the strain path during deep drawing, a steady state was assumed in the flange part of deep drawn cup. The final stable orientations were strongly dependent on the initial location in the blank. The evolution of anisotropy of DP steel sheets has been demonstrated through comparison of plastic strain rate vector at the different plastic strain levels.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1994년도 봄 학술발표회 논문집
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• pp.181-188
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• 1994

Generally, the structural material shows rate dependent behaviors, which require to constitute different strain-stress relations according to strain rates. Conventional rate- independent constitutive equations used in general purpose finite analysis programs are inadequate for dynamic finite strain problems. In this paper, a rate dependent constitutive equation for elastic-plastic material was developed. The plastic stretch rate was modeled based on slip model with dislocation velocity and density so that there is no yielding condition, and no loading conditions. Non-linear hardening rule was also introduced for finite strain. Material constants of present constitutive equation were determined by experimental data of mild steel. The constitutive equation was applied to uniaxile tension. It was appeared that the present constitutive equation well simulates rate dependent behaviors of mild steel.

• International Journal of Quality Innovation
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• 제5권2호
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• pp.106-121
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• 2004

This paper investigates customer knowledge management activities of Taiwan's plastic industries. The results demonstrate that the bulk of customer knowledge comes from data related to customer purchase orders and complaints. Furthermore, marketing, production, and research and development are the main departments that developed and reuse customer knowledge. The benefits derived from knowledge management for enterprises do not vary with the position of the vendor on the business scope. In addition, the benefits derived by customers from knowledge management are directly related to the benefits gained by the five major business functions, while the benefits derived from the customer knowledge management are also directly related to customer satisfaction. Summarizing the above results, an Acquisition-Development-Reuse (ADR) model is proposed and can provide the enterprises with a systematic reference model when the business attempts to construct a customer knowledge management system.

• Journal of Welding and Joining
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• 제21권1호
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• pp.54-59
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• 2003

In the present work, a formula for plate deformation produced by line heating, in terms of process parameters such as heat input and plate dimensions, is developed analytically using an eigenstrain concept. The residual deformation that was due to thermal process was depends on the magnitude and region of plastic strains at heating zone. The magnitude of plastic strains was determined by disk model and its region was calculated using the Rosenthal"s solution. The vertical displacement of the plate was analyzed by using an infinite laminated plate theory to consider a cuboidal inclusion with an eigenstrain. Comparison of the calculated results and experimental data shows the accuracy and validity of proposed method.thod.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.543-547
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• 2004

The molding characteristics of large-sized orthogonal stiffened plastic plates were investigated in the present study. Models with the geometry of 1800$\times$600$\times$12mm and 1200$\times$600$\times$12mm were designed for injection molding(IM) and injection-compression molding(ICM), respectively. To determine a mold system and reduce the warpage of the presented model after molding process, IM and ICM analyses using MOLDFLOW$^{TM}$ were performed. Also, the experiments were performed to verify the suggested mold system. It was shown that the change of molding method could significant effect on the warpage of designed model.l.