• 한국산학기술학회논문지
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• 제13권5호
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• pp.2414-2419
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• 2012

본 논문에서는 물 재이용 펌프 시스템의 에너지 효율적 운전 방법을 제안한다. 1시간 단위의 시간대에서 최적운전제어를 위해 예측구간 스위칭방법과 선형계획법을 적용하고 에너지 비용은 경부하, 중부하, 그리고 최대부하를 포함한 TOU 요금과 피크요금을 통해 산정하도록 한다. 물 재이용 펌프시스템에서의 최적운전은 TOU 요금과 피크요금을 포함한 에너지 비용을 최대로 줄일 수 있도록 수행한다. 시뮬레이션을 통해 제안한 최적운전방법을 적용하면 많은 전력 에너지 비용의 절감과 전력계통의 안정성 향상을 확인할 수 있다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.1134-1141
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• 2011

Costs have long since become a major issue in railway system analysis, attention is not limited to the acquisition costs alone, but encompasses all costs involved in the use and disposal of the systems. Concepts such as Life Cycle Cost(LCC), Costs Of Ownership(COO), or Total Ownership Cost(TOC) are more and more frequent in any document dealing with system analysis. Most of railway projects have applied this LCC Model to evaluate effectiveness of system acquisition cost. But these action of LCC model does not applied all the rest of system life cycle period due to the differences of its responsibility. This is why a study has been undertaken by the operation party to harmonize the most important aspects of the LCC model. This study focused on these and other objectives for introduction of method and needs for an action plan for maintenance actions involved relevant cost allocation.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2017년도 추계학술대회
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• pp.33-34
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• 2017

This paper presents a linear droop control scheme based on the generation costs of DGs in an autonomous DC microgrid. Unlike the proportional power sharing of the conventional droop control, in the proposed control algorithm, the minimum output voltage range is adjusted and the droop coefficients are regulated according to the generation costs of DGs. As a result, the DGs with lower costs supplies more power in comparison with those with higher costs. Therefore, total generation cost of the system is reduced significantly. The proposed method is simple to implement and it does not require the centralized controller and communication links.

• 대한안전경영과학회:학술대회논문집
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• 대한안전경영과학회 2012년 춘계학술대회
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• pp.371-380
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• 2012

Although all costs concerned in transportation be separated by region and each terms and conditions of Incoterms that state cleary them who have to pay the charges. But, almost lcl exporters donot want to pay their charges the carriers at loading port eventhough they make the contracts with the importer as FOB and CFR of Incoterms. And the carrier have been do not bill the FOB charges to the shipper. Now, there are no more Incoterms in LCL transportation. So, the importer have been payed loading port charges twice, first, the contract with the shipper, secondly, through the destination charge. These problems make decreasing of trading volume and increasing of logistics costs. We suggest every traders and carriers separate the costs as per the price terms and conditions of incoterms and bill/receive the costs separated the trader who have to pay the charges as per their price terms. It will bring mutual success in the world and increasing trade.

• 산업경영시스템학회지
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• 제24권65호
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• pp.23-30
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• 2001

In this paper, we consider an inventory system in case the toleration to be inventory stortage under the price discount. It has been observed that suppliers suggest a free addition of marketing policy like a price discount. A major reason for a supplier to offering a free addition to a customers is to stimulate the demand and to decrease a total cost. but, If we not adapting to the toleration to be inventory-lacking, we will a burden holding costs in a relation to the holding of inventory. This paper, is a combination of the toleration of inventory shortage and the condition of discount price. The costs are defined as the sum of the ordering, holding, shortage, purchasing and opportunity costs. Based on numerical results, conclusions follow about the total of operation costs the division of the shortage rate of inventory.

• 교육시설 논문지
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• 제23권6호
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• pp.27-34
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• 2016

Although the scale and number of university facilities have increased, the maintenance of these facilities has not been efficient as maintenance costs incurred during facility operation periods, as well as management time, have not been sufficiently considered. In this study, the maintenance record data of national universities was compared and analyzed to analyze factors that incur maintenance costs according to the uses and costs of the facilities. According to the results, the number of cases of maintenance and repair work for basic educational facilities was shown to be the largest, accounting for 79%. The number of maintenance and repair work occurred according to work type was examined. According to the results, the highest ratio of maintenance and repair work occurred in the field of construction, specifically, the maintenance costs required for facility supplementation accounted for the highest ratio. Maintenance costs per unit area decreased over time in the newer university facilities, while showing a tendency to increase in older university facilities. However, there were cases where maintenance costs did not show any trends due to factors such as the limited maintenance budgets owing to the characteristics of public service facilities and facilities in the stage of deterioration or destruction after the stage of stabilization. This study is considered to be helpful for efficient university facility maintenance plans and budget calculations.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2004년도 추계학술대회 및 정기총회
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• pp.35-38
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• 2004

Global competitive pressures are asking industrial companies to find the best way to meet their customer's requirements, reduce the costs of products, and increase productivity. Quality improvement has been proposed and implemented as a primary means of achieving these purposes. The quality improvement usually includes a goal of reducing the costs due to poor quality. While these costs of poor quality (COPQ) are not known precisely, they are known to be very high. Also, they may be underestimated by the hidden costs due to non-value activities, such as potential lost sales, costs of redesign due to quality reasons, and extra manufacturing costs due to defects, etc. In any manufacturing or service operation, all actions and resource expenditures of a company should be focused on creating value for customers. Any activity or resource of not creating the value for customers could be regarded as waste, which consequently causes the COPQ. Some companies did use dashboards to understand and identify value added or non-value added activities in order to reduce or eliminate wastes. These dashboards must be properly designed to consider inherent differences in manufacturing or service operations among business organizations. In addition, a structured quality improvement program such as the Six Sigma must support these dashboards. In this paper, a case study of designing dashboards for evaluating and reporting the COPQ in business units is presented.

• 대한교통학회지
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• 제14권1호
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• pp.69-80
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• 1996

In most cities, travel demand is distributed along long corridors and its destinations tend to concentrate in a central business district. For this kind of many-to-one or one-to-many travel demand pattern, a zonal operation of buses can be an efficient bus operation technique in which a long bus-demand corridor is divided into service zones and each service zone is provided with its own bus route connecting the service zone and single destination separately. This paper develops models of the total transportation costs for a single-zone operation and 2-zonal operation of buses for a long demand corridor with single destination in terms of various cost parameters, demand density, bus operation speeds, and location of the boundary between two service zones. In this study the total transportation cost is assumed to consist of the bus operation cost, passenger waiting cost and passenger travel time cost. It was proved that a zonal operation of buses can be more efficient than a single-zone operation for certain circumstances of the system and an boundary condition between two operation techniques was obtained. Also, several case studies were performed for various values of the cost parameters.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 춘계 학술논문 발표대회
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• pp.47-48
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• 2012

In this study, the CO₂ emission and economic efficiency of high-rise apartment houses were evaluated, and were analyzed as a way to establish database on the evaluation of environment-friendliness of high-rise buildings. To that end, standard of buildings to be evaluated were proposed through analysis of the designing guideline for high-rise apartment houses proposed by Seoul city, and CO₂ emission of the subject buildings were evaluated based on the characteristics of materials admitted into each building and the amounts of energy consumed during lifecycle period. In addition, the initial costs in construction stage and annual costs in operation stage were set as analysis parameters, and along with calculation of direct cost by the consumption of construction materials and energy, the costs of CO₂ emission were evaluated and analyzed. As a result, the CO₂ emission and economic efficiencies of high-rise apartment houses by construction stage and operation stage could be analyzed quantitatively.

• 디지털산업정보학회논문지
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• 제8권4호
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• pp.53-62
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• 2012

U-City means the high-tech city that applied ubiquitous technology and information communication technology. U-City aims to intensify urban competitiveness and to improve the quality of residents' life through efficient management of the urban. Currently, 77 U-City projects is underway. The each project cost and scale estimate is not clear in the absence of the U-Service Standardization Model. So, many of the project are trouble about making a production the proper number of U-Service or the cost of project. The excessive service construction is reflected on the construction costs, which leads to the rise of sales price and passes onto the executor of a project as a burden of the project costs, and the problem of the delay of the change-over occurs due to supporting the operation costs for the operation of the constructed service and the demand for additional installation of facilities between a local autonomous entity and the executor of a project. In this paper, we suggested the U-Services Construction Standardization Methods and proposed the standardization services guideline of crime prevention services. U-City services in the future are able to maintain the consistency of the system through the utilization of the proposed standard model. As a result, the U-City project's pre-estimated cost and scale can be extracted.