• 한국항공운항학회지
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• 제20권3호
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• pp.35-43
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• 2012

Medium size rotorcraft consist of approximately 5,000 key components. The components must satisfy the target weight and performance requirement through optimization. Therefore a rotorcraft component has approximately 100 times higher unit cost for mass production than the equivalent of an automobile's, along with huge development cost. Configuration management consists of four main parts : configuration identification, configuration control, configuration audit, and data management. In development programme, configuration management is one of the methods to save development cost, and setting a well-structured configuration management system according to the Military Standard is an important factor in success of the programme. The paper proposes a configuration management system suitable for development of various multi-use components development and presents that the configuration management was performed successfully during dual-use component development programme using the established system.

• 소성∙가공
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• 제24권3호
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• pp.181-186
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• 2015

Many in the industrial world that consume high amounts of energy are trying to reduce energy when manufacturing their products. Energy saving during manufacturing is a cost reduction. Reduced cost is necessary for profit improvement. The Piston Under Drive Brake used in the current study is an automotive transmission part. The original machining after hot forging was changed to machining after cold forging of a plate in order to save energy and cost. Two extrusion shapes along the outer diameter caused decreased tool life because of the interrupted cut during turning. Therefore, a thickness reduction of two extrusion areas in the outer diameter was needed. The current study suggests an effective way to reduce the thickness of interrupted cut by using progressive blanking.

• 한국항해항만학회지
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• 제27권3호
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• pp.297-306
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• 2003

As the competition in the liner shipping industry is becoming fiercer, the shipping company is trying to find the way to keep the best competitive position by reducing the cost level as low as possible and offering the best quality of service to their customer. In order to achieve this goal, the selection of port and terminal that have the best quality of service and cost effective structure is essential for the shipping line, where they can only have a chance to save the money. In this context, the paper compares three European container terminals in order to understand the factors that have to be considered in the decision making process for the selection of terminal. And its advantages and disadvantages of each type of container terminal operation system were analyzed from the liner shipping company's point of view in terms of cost, time, flexibility, stability, hinterland connection, geographical position and terminal productivity. It is obvious that the cost factors are very important for liner shipping company to select their terminal. However, there might be even more important factors than the cost factors, such as quality of port and terminal service, mutual trust, and possibility of future development.

• 한국환경과학회지
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• 제18권6호
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• pp.603-608
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• 2009

Activated sludge sewage treatment processes are difficult to be controlled because of their complex and nonlinear behaviour, however, the control of the dissolved oxygen level in the reactors plays an important role in the operation of the facility. For this reason, this study is designed to present a system which accurately measures DO, MLSS, pH and ORP in the aeration tank to alleviate situations above and provide the automatization of a sewage treatment plant (STP) using new DO control system. The automatic control systems must be guaranteed the accuracy. Therefore, the proposed automatic DO control system in this study could be commercial applications in the aeration tanks by means of operating cost analysis and user-friendly for operation and maintenance. We could get accurate data from the lab tank which has water quality checker because there was no vortex and air bubble during the measurement process. Improvement of confidence in the lab tank enabled effective and automatic operation of sewage treatment plants so that operation costs and manpower could be saved. If this result is put in place in every sewage treatment plant nationwide for practical purposes, it is estimated to cost 18.5 million dollars in installing the lab tank and to save 9.8 million dollars in management cost a year, except for cost saved by automation.

• 전기학회논문지
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• 제63권2호
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• pp.205-210
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• 2014

The micro grid considered in this paper consists of a diesel generator, a photovoltaic array, a wind turbine, a fuel cell, and a energy storage system. This paper explains and simulates the micro grid components in terms of accuracy and efficiency of having a system model based on the costs of fuel as well as operation and maintenance. For operational efficiency, the objective function in a diesel generator consists of the fuel cost function similar to the cost functions used for the conventional fossil-fuel generating plants. The wind turbine generator is modeled by the characteristics of variable output. The optimization is aimed at minimizing the cost function of the system while constraining it to meet the customer demand and safety of micro grid. The operating cost in fuel-cell system includes the fuel costs and the efficiency for fuel to generate electric power. To develop the overall system model gives a possibility to minimize of the total cost of micro grid. The application of optimal operation can save the interruption costs as well as the operating costs, and improve reliability index in micro grid.

• 산업경영시스템학회지
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• 제32권2호
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• pp.57-65
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• 2009

In continuous review inventory model, (${\varrho}$, ${\gamma}$) system, order quantity(${\varrho}$) and reorder point(${\gamma}$) should be determined to calculate inventory-related cost that consists of setup, holding, and penalty costs. The procedure to obtain the exact value of ${\varrho}$ and ${\gamma}$ is complex. In this paper, a regression analysis is proposed to get the approximate inventory-related cost without the determination of ${\varrho}$ and ${\gamma}$ in the case that the standard deviation(${\sigma}$) of the lead time demand is small or that the mean(${\mu}$) of the lead time demand is proportional to ${\sigma}$. To save inventory-related cost, central warehouses with (${\varrho}$, ${\gamma}$) system can be built. Central warehouse can provide some stores with products with the consideration of the tradeoff between inventory-related cost and transportation cost. The number and the location of central warehouses to cover all the stores are determined by a regression-based approach. The performance of the proposed approach is tested by using some computational experiments.

• 한국공간구조학회논문집
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• 제21권3호
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• pp.77-84
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• 2021

In this study, In order to apply the U-flanged truss hybrid beam to the actual construction site, the structural design of the basic module of the middle and low-rise neighborhood living facilities was performed according to the Korea Design Standard, and the construction cost and construction period were compared with the traditional reinforced concrete structure system. As a result of analyzing the construction cost for the basic module, if the U-flanged truss hybrid beam and D-Deck slab system are used, the construction cost can be reduced by 86% compared to the traditional reinforced concrete structure system. In addition, as a result of analyzing the construction period for a floor area of 1,000m², using the U-flanged truss hybrid beam and D-Deck slab system can save 2.0days in construction period compared to the traditional reinforced concrete structure system. Therefore, the U-flange truss hybrid beam can secure sufficient economic feasibility compared to the existing reinforced concrete method in terms of cost reduction and shortening of construction period.

• 한국건설관리학회:학술대회논문집
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• 한국건설관리학회 2006년도 정기학술발표대회 논문집
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• pp.123-130
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• 2006

최근 정부는 임대형민간투자사업(BTL, Build Transfer Lease)방식을 적극 도입함으로써 민간의 축적된 지식과 경험을 이용하여 보다 효율적인 사회간접자본(Social Overhead Capital) 확충을 도모하고 있다. 공공부분 및 사업시행자 등 민간투자사업의 사업기획단계에서 운영단계에 이르기 까기 전문화된 기술과 경험을 바탕으로 한 설계를 통하여 시설물 사용자의 요구를 충족시키는 동시에 창의적 기법을 총동원 예산과 리스크 범위내에서 최대한의 효율과 수익 창출을 극대화하려는 노력이 필요하다. 이처럼 BTL등 민간투자사업의 투자가치(Value for Money)를 극대화시키기 위해서는 VM(Value Management) 방법론의 효과적인 사용이 불가피하다. 여기서는 BTL 사업에서의 "VE job Plan" 활용 절차 및 적용방안을 제시하였다. BTL 사업에서의 효율적인 "VE job Plan"을 제시하기 위하여 국내 민간투자사업 및 VE 추진을 위한 법적제도의 변화를 분석하였다. 국내 BTL 사업 수행절차 및 BTL 사업에서의 VE적용방안을 "VE job Plan"과 함께 제시하였다. 실제 적용사례 연구를 통하여 BTL 사업에서의 "VE job Plan"의 작성과 작성된 프로세서를 활용한 의사결정 및 대안평가 방법을 제시하였으며, 속성 중 비용은 LCC(Life Cycle Cost : 이하 LCC) 분석결과를 바탕으로 평가하였고, 프로젝트 기능개선을 위한 평가방법으로는 기술적 FAST도를 사용하여 분석하였다. 사례는 "대구시립미술회관" 사업자 선정을 위한 BTL VE 활동을 통해 보다 향상된 가능의 개선, 비용절감 및 양질의 서비스 수준을 제공한 VM사례를 소개하였다.

• 보건행정학회지
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• 제15권2호
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• pp.1-15
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• 2005

The aim of this study was to compare medical cost of hospice care and that of conventional care during the last year of life, and identify factors that influenced the cost. From January to August 2003 592 terminal cancer patients receiving care from 5 hospice care units and 2 hospice care teams in general hospitals were enrolled to case group. Two hundreds and seventy two terminal cancer patients receiving conventional care from 7 general hospitals were enrolled to hospital-based control group, and 1,636 terminal cancer patients from 122 general hospitals located in same regions with the 7 hospitals were enrolled to community-based control. We used characteristics and medical cost from data of National Health Insurance Cooperation. Total medical cost per beneficiary in cases was about 10 millions won, 14.5 millions in hospital-based controls and 11.1 millions in community-based controls. The hospice care saved $45\%$ over the last year of life compared with hospital-based controls (p<0.0001). Saving of inpatient cost account for approximately $80\%$ of saving per beneficiary. Hospice care saved $29\%$ of medical cost per hospitalization day compared with hospital­based controls and $17\%$ compared with community-based controls (p<0.0001). Multiple regression analyses showed that hospice care significantly saved the medical cost. This study suggest that hospice care save medical cost compared with hospital-based control and community-based control. Most of saving of inpatient cost account for approximately $80\%$ of saving of medical cost.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.162.2-162.2
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• 2010

The energy storage system is considered to be one of the useful devices for energy storing and recycling. the energy storage system can save energy cost and stabilize the system voltage. This paper presents the development of two energy storage systems. One is 750V system for light rail system. the other is 1500V system for heavy rail system.