• 대한산업공학회지
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• 제30권4호
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• pp.346-354
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• 2004

Most industrial logistic systems have focused on carrying products from manufacturers or distribution centers to customers. In recent years, they are faced with the problem of integrating reverse flows into their transportation systems. In this paper, we address the vehicle routing problems with mixed delivery and pick-up(VRPMDP). Mixed operation of delivery and pick-up during a vehicle tour requires rearrangement of the goods on board. The VRPMDP considers the reshuffling time of goods at customers, hard time windows, and split operation of delivery and pick-up. We construct a mixed integer mathematical model and propose a new genetic algorithm named GAMP for VRPMDP. Computational experiments on various types of test problems are performed to evaluate GAMP against the modified Dethloff's algorithm. The results show that GAMP reduces the total vehicle operation time by 5.9% on average, but takes about six times longer computation time.

• 한국산학기술학회논문지
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• 제18권6호
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• pp.653-661
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• 2017

본 논문은 탄소배출 규제와 같이 새롭게 변화하는 물류 환경에서 유통업체들이 올바른 물류전략을 선정하기 위하여 탄소배출을 고려한 두 물류전략의 총 운영비용의 비교 분석 연구를 수행하였다. 본 연구에서는 물류전략간 운영비용 비교를 위하여 기존 EOQ(Economic Order Quantity) 모형을 활용하여 국내의 물류환경 및 탄소배출을 고려한 모형으로 확장하였고, 이 모형을 바탕으로 실증연구 분석을 수행하였다. 실증 연구로는 대형 유통업체의 농산물 유통을 대상으로 하여 기존의 물류 전략과 직배송 물류 전략의 운영비용 및 경제적 주문량을 산정하고 분석하였다. 실증연구 결과 농산물을 운송함에 있어 직배송 물류전략이 기존 물류전략 대비 50% 이상의 운영비용 절감효과가 있는 것으로 분석되었고, 이는 직배송 물류전략이 기업의 운영비용 절감에 더 효과적인 것으로 판단할 수 있다. 결론적으로, 탄소배출을 고려하였을 때 직배송 물류전략이 기존 물류전략보다 경제적 환경적인 효과가 있다고 분석될 수 있으며, 농산물의 신선도도 함께 높이는 전략이라고 판단된다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 C
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• pp.1059-1062
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• 1998

This paper which can simulate FRIENDS(Flexible Reliable Intelligent Electrical eNergy Delivery System) model of distribution electrical system presents a new algorithm. In the operation of FRIENDS model, dispersed energy storage(DES) systems have an important role. We can use the active and reactive power of DES to control customer's voltage. In this, the former means load levelling operation and the later means voltage control operation of DES. We focus our research on load levelling operation of DES. We develope an algorithm to get an optimal capacity and operation schedule of DES and then apply it to the FRIENDS model. The results show the effectiveness of the proposed method.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2008년도 정기학술발표대회 논문집
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• pp.591-596
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• 2008

건설 공사에서 발주방식은 프로젝트의 성패에 많은 영향을 준다. 이 논문은 대형공사에 효율적인 기술제안형 입찰방식 적용에 관한 연구를 목적을 갖는다. 본 연구의 연구절차는 다음과 같다. 대형공사 발주 및 발주방식에 대한 이론적 고찰 실시하였고, 다음 국내 외 발주제도 방식을 조사하여 분석하였고, 이에 따른 대형공사의 발주 실태 및 문제점을 도출하였다. 이에 따라 대형공사의 경우 프로젝트의 특징 및 목적을 잘 반영하지 못한다는 문제점 등이 분석되었고, 분석된 문제점을 보안하기 위해서 기술제안형 입찰방식을 도입하기 위해서 현재 재정된 기술제안형 입찰 방식의 개념 및 절차에 대한 분석을 하였고, 이를 통하여 결과적으로 대형건설공사에 효율적으로 적용하기 위해서 기술제안서 작성 및 평가 반영을 위한 비가격 요소와 가격 요소로 분류하고 각 요소별 항목을 제시하였다.

• 대한지리학회지
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• 제38권1호
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• pp.104-126
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• 2003

본 연구는 농협 농산물 물류센터의 상적, 물적 유통체계를 파악하고, 물류의 효율성과 집약화를 위해 설립된 청주 물류센터의 계절별 농$.$축$.$수산물의 입하지를 고찰하고자 한다. 그리고 각 상품의 판매액에 의한 배송의 지역유형과 지역특성과의 관계를 밝히는 것을 연구목적으로 한다. 그 결과 청주 물류센터는 충북을 핵심지역으로 전국에서 농$.$축$.$수산물을 입하하여 충북과 충남, 대전시 일부 지역에 배송을 집중화시키고 있다. 이는 청주 물류센터가 취급하고 있는 농$.$축$.$수산물이 신선도를 요하는 상품이기 때문에 물류센터에서 상대적으로 가까운 지역에서 주로 입하하여 근거리 배송을 하는 지역 물류시스템을 형성하고 있다는 것이다. 이러한 농$.$축$.$수산물의 배송은 수급관계라는 경제원칙뿐만 아니라 물류센터의 판매전략도 크게 작용하고 있다.

• 한국수소및신에너지학회논문집
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• 제27권1호
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• pp.22-28
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• 2016

It is necessary to store and supply hydrogen isotopes for Tokamak operation. A storage and delivery system (SDS) is used for storing hydrogen isotopes as a metal hydride form. We designed and fabricated a depleted uranium (DU) bed to store hydrogen isotopes. The rapid storage of hydrogen isotopes is very important not only for safety reasons but also for the economic design and operation of the SDS. The delivery rate at the desorption temperatures without the operation of a dry pump was analyzed in comparison with that with the operation of the dry pump. The effect of the initial desorption temperatures on the dehydriding of the DU without the operation of the dry pump was measured. The effect of the initial desorption temperatures on the dehydriding of DU with the operation of the dry pump was also measured and analyzed. The primary pressure on the desorption temperatures without the operation of the dry pump was analyzed in comparison with that with the operation of the dry pump. The temperature gradient of the coil heater and the primary vessel was also analyzed. Our results will be used to develop pilot scale hydrogen isotope processes. It was confirmed that dehydriding of a medium-scale DU bed has enabled without the operation of the dry pump.

• 산업공학
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• 제13권4호
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• pp.680-687
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• 2000

The objectives of this research are to establish the operation scheduling and the preventive maintenance system in order to optimize the operation of mailing center. For the optimal operation scheduling of mailing process, the existing workflow of mailing process and that of required time are investigated prior to simulation modeling. The simulation experiments are conducted to increase the nextday delivery rate. The best alternative whose nextday delivery rate up to 100% is selected based the AHP(Analytic Hierarchy Process) method. The optimal work scheduling of all mailing centers are also presented. In addition, the CMMS(Computerized Maintenance Management System) for preventive maintenance is introduced for efficient operation of highly automated facilities of mailing center.

• 제어로봇시스템학회논문지
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• 제17권6호
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• pp.566-572
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• 2011

In recent semiconductor and FPD (Flat Panel Display) manufacturing processes, high clean-class delivery operation is required more and more for short working time and better product quality. Traditionally SLIM (Single-sided Linear Induction Motor) is widely used in the liner drive applications because of its simplicity in the rail structure. A magnetically levitated (Maglev) unmanned vehicle with SLIM traction, which is powered by a CPS (Contactless Power Supply) can be a high precision delivery solution for this industry. In this paper unmanned FPD-carrying vehicle, which can levitate without contacting the rail structure, is suggested for high clean-class FPD delivery applications. It can be more acceptable for the complex facilities composed with many processes which require longer rails, because of simple rail structure. The test setup consists of a test vehicle and a rounded rail, in which the vehicle can load and unload products at arbitrary position commanded through wireless communications of host computer. The experimental results show that the suggested vehicle and rail have reasonable traction servo and robust electromagnetic suspensions without any contact. The resolution of point servo errors in the SLIM traction system is accomplished under 1mm. The maximum gap error is ${\pm}0.25mm$ with nominal air gap length of 4.0mm in the electromagnetic suspensions. This type of automated delivery vehicle is expected to have significant role in the clean delivery like FPD glass delivery.

• 한국조리학회지
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• 제4권
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• pp.189-209
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• 1998

This study attempts to approach to the Peter Jones' and Marian C. Spears' foodservice delivery system with a focus on their theory. First, ten stages and ten dedicated foodservice delivery systems were introduced. And the author made an attempt to analyze the Peter Jones' ten stages and ten dedicated foodservice delivery systems and then the author's suggestions about them were presented. Second, the author explain the Marian C. Spears' four types of foodservice operations enabling us to establish the type of foodservice operation newly.

• 산업융합연구
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• 제5권2호
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• pp.21-32
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• 2007

This paper deals with the sequencing problem in the operation of the manufacturing systems with the constraint of buffer capacity. Some of studies for this theme have been progressed for several years. And then most of them considered only one objective, such as maximum lateness, machine utilization, makespan, mean flowtime and so on. This study deal with two objectives of the delivery for customers and the idle time of machines for producers. For the decision of sequence, the utility function is used. The developed heuristic algorithm presents a good solution. Through a numerical example, the procedures of the job sequencing is explained.