• 한국경영과학회지
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• 제23권3호
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• pp.91-108
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• 1998

Automated Storage and Retrieval Systems (AS/RSs) are an important facility for modern material management. The expected benefits of these capital-intensive facilities are gained when their control policies and their physical design parameters are determined simultaneously. In this paper we present several analytical models that capture the impact of the storage assignment policy and of the rack design on the expected storage and retrieval times. Sequential and interleaved service modes are considered for sequencing the storage and retrieval requests. We further investigate the impact of the rack structure on the relative performance of the following storage assignment policies : closest open location (random), full turnover-based policy, and class-based. Our analysis clearly indicates that significant savings in crane travel time are realized when implementing full turnover-based policy, rather than random. These savings become more and more pronounced as the profile of the storage racks approaches the square-in-time shape. Furthermore, it is shown that a class-based policy, with a small number of storage classes, will capture most of these savings and be easier to manage in practice.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 1991년도 추계학술대회 논문집
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• pp.52-55
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• 1991

A fuel cell is a device that directly converts the chemical energy of reatants into low voltage d$.$c electricity. The high temperature fuel cell (MCFC, SOFC)is an excellent electric generator with regard to preservation of the environment and the energy-savings. The purpose of this research is to investigate technical issue and research need for practical use of high temperature fuel cell.

• 경영과정보연구
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• 제34권5호
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• pp.277-293
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• 2015

저축은행은 서민의 금융기관으로서 일반은행에 비하여 규모가 작고 상대적으로 리스크 관리도 취약하다. 또한 일반 은행과 같이 예금자보호법에 따라 5천만원 이하의 예금은 보호되기는 하지만 일반서민이나 중소기업이 주된 고객이라는 점에서 일반 기업과 차이가 있다. 따라서 지배주주의 사적이익추구로 인하여 극단적으로 영업정지등의 사태가 발생할 경우 그로 인한 이익의 침해는 소액주주 이외에도 다수의 예금자, 정부, 일반 국민들도 잠재적인 피해를 볼 수 있고 그로 인한 공익비용은 일반기업보다 훨씬 크다 할 수 있다. 지배주주의 지분율과 관련한 가설로 이익침해가설과 이해일치가설로 상반되는 주장이 존재한다. 먼저, 외부 소액주주들에 대한 지배주주의 이익침해가설(expropriation of minority shareholder hypothesis)에서는 지배주주의 지분율이 증가할수록 경영자는 이익을 증가시켜 보고할 유인이 있다. 또한 이해일치가설(convergence of interest hypothesis)은 지배주주 지분율이 증가함에 따라 경영자는 이익을 감소시켜 보고할 유인이 있다. 이에 본 연구는 국내 상호저축은행 대상으로 최대주주 지분율이 기업의 내부통제의 질에 어떠한 영향을 미치는 지에 대한 실증적 연구를 수행하고자 한다. 분석 결과, 최대주주지분율은 내부회계관리제도 취약점 공시에 유의적인 양(+)의 영향을 미치는 것으로 나타났다. 이것은 최대주주지분율이 높을수록 회계투명성이 저하되어 내부통제의 질이 낮아져서 내부회계관리제도 취약점 보고가능성이 높아진다는 것을 의미한다.

• 콘크리트학회지
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• 제27권5호
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• pp.36-39
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• 2015

• Computers and Concrete
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• 제3권5호
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• pp.313-334
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• 2006

A novel formulation aiming to achieve optimal design of reinforced concrete (RC) structures is presented here. Optimal sizing and reinforcing for beam and column members in multi-bay and multistory RC structures incorporates optimal stiffness correlation among all structural members and results in cost savings over typical-practice design solutions. A Nonlinear Programming algorithm searches for a minimum cost solution that satisfies ACI 2005 code requirements for axial and flexural loads. Material and labor costs for forming and placing concrete and steel are incorporated as a function of member size using RS Means 2005 cost data. Successful implementation demonstrates the abilities and performance of MATLAB's (The Mathworks, Inc.) Sequential Quadratic Programming algorithm for the design optimization of RC structures. A number of examples are presented that demonstrate the ability of this formulation to achieve optimal designs.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2008년도 추계학술대회 논문집
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• pp.234-237
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• 2008

It was reported that the semi-solid forming process has many advantages over the conventional forming process, such as a long die life, good mechanical properties and energy savings. It is very important, however, to control liquid segregation to gain mechanical property improvement of materials. During forming process, Rheology material has complex characteristics, thixotropic behavior. Also, difference of velocity between solid and liquid in the semi-solid state material makes a liquid segregation and specific stress variation. Therefore, it is difficult for a numerical simulation of the rheology Process to be Performed. General Plastic or fluid dynamic analysis is not suitable for the behavior of rheology material. The behavior and stress of solid particle in the rheology material during forging process is affected by viscosity, temperature and solid fraction. In this study, compression experiments of aluminum alloy were performed under each other tool shape. In addition, the dynamics behavior compare with Okano equation to Power law model which is viscosity equation.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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• pp.216-217
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• 2014

Optimum finishing position, thickness and phase change temperature of winter and summer season were selected and suitability of finishing materials was evaluated based on temperature measurement of specimens applying the coating material mixed phase change materials(PCM). As a result, when finishing position was interior and finishing thickness of coating material mixed n-Octadecane(28℃ PCM) was 4mm, thermal performance was effective. n-Octadecane in summer season and n-Hexadecane(18℃ PCM) in winter season are indicated effective on energy savings, respectively.

• 한국철도학회논문집
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• 제7권2호
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• pp.77-84
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• 2004

In order to determine the most suitable material system for achieving the lightweight design while fulfilling the design requirements of carbody structures of Korean Tilting Train eXpress(TTX), aluminum carbody. composite carbody, and hybrid carbody combined with aluminum and composite structures were considered in the present study. The finite-element analysis was used to verify the design requirements or the TTX carbody structures with the material system considered in the design stages. The stresses in the carbody structures and deflections of underframe against static load cases were used as design criteria. The results show that the hybrid carbody structures are beneficial with regard to weight savings and structural integrity in comparison to aluminum and composite carbody structures.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.462-467
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• 2004

In order to determine the most suitable material system which can achieve the lightweight design and fulfill the design requirements of carbody structures of Korean Tilting Train eXpress (TTX), aluminum carbody, composite carbody, and hybrid carbody combined with aluminum and composite structures were considered in present study. The finite-element analysis was used to verity the design requirements of the TTX carbody structures with the material system being considered in the design stages. The stresses in the carbody structures and deflections of underframe against static load cases were checked as design criteria. The results show that the hybrid carbody structures are beneficial with regard to weight savings and structural integrity when compared to aluminum and composite carbody structures.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2015년도 추계 학술논문 발표대회
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• pp.17-18
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• 2015

In the case of concrete recently manufactured with a concrete mixing truck, although aggregate and cement are used as the main ingredients, from a costs savings perspective, low quality aggregates are processed and used as concrete aggregate. In the case of these low quality aggregates, the unit volume and unit binder weights are increased for manufacturing, and due to this problems such as dry shrinking of the architecture and economic infeasibility have arisen. Therefore by changing the aggregate material and the unit binder weights that are currently being distributed, this research analyzes the influence on concrete.