• 제목/요약/키워드: operational cost

검색결과 884건 처리시간 0.025초

Multi-objective parametric optimization of FPSO hull dimensions

  • Lee, Jonghun;Ruy, Won-Sun
    • International Journal of Naval Architecture and Ocean Engineering
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    • 제13권1호
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    • pp.734-745
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    • 2021
  • In order to achieve a good and competitive FPSO design, the building cost and the motion performances are the two most critical and conflicting KPIs to be considered. In this study, the author's previous work (Lee, et al., 2021) on the optimization of an FPSO's hull dimensions with 1800 MBBLs storage capacity at Brazil field was extended using a multi-objective parametric optimization with the hull steel weight and the operability which are closely related to the building cost and the operational cost during the lifetime, respectively. For the purpose of more realistic and practical FPSO design, the constraints related to crew comfort and the safe helicopter take-off and landing operation were newly added. Also, the green water on deck was calculated accurately to check the suitability of the designed freeboard height using a newly developed real-time calculation module for the relative wave elevations. With aids of this updated optimization formulation, we presented multiple optimal FPSO dimensions expressed as a Pareto set which aids FPSO designers to conveniently select the practical and competitive dimensions. The excellence of the developed approach was verified by comparing the optimization results with those of FPSOs dimensioned for operation at West Africa and Brazil field.

Analysis of Financial Management Activities in Elementary School Foodservices (초등학교급식에서 수행되는 급식비 관련 재무관리 업무분석)

  • Choe, Eun-Hui;Lee, Jin-Mi;Gwak, Dong-Gyeong
    • Journal of the Korean Dietetic Association
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    • 제2권2호
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    • pp.123-140
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    • 1996
  • The purpose of this study was to examine financial management practices in elementary school foodservices. Respondents were asked to provide information on demographics, operational characteristics, financial management activities(responsibility, importance and time demand). Data were collected from 106 elementary school foodservice using the mail questionnaire. The results were as follows 1. Time demand of 14 financial management activities was examined. The results of time-demand showed that most financial activities were performed about once per month. Reporting, inventory checking and production cost accounting were performed several times per week. 2. Major financial management activities performed by school dietitians were inventory checking, record keeping, production cost accounting, and foodservice operation planning. 3. Results of the importance rating of 14 financial management activities showed that the production cost accounting, budgeting, controlling meal costs, reporting the national treasury accounts, and inventory checking were rated as very important(4.00-4.49). Factor analysis was conducted on the importance ratings. Five activities were differentiated such as budgeting, record keeping, cost controlling, cost accounting, and reporting. The cost controlling task was identified at the most important one among them. 4. Important ratings for reporting were found to be significantly different by age, and years of experience. The younger and the less experienced were responded with higher scores on reporting. Analysis of variance for the importance scales by meal costs per one person, food cost percentage, labor cost percentage was conducted, but significant differences were not founded.

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Decommissioning Cost Estimation of Kori Unit 1 Using a Multi-Regression Analysis Model (회귀 분석 모델을 이용한 고리 1호기 해체 비용 추정)

  • Joo, Han Young;Kim, Jae Wook;Jeong, So Yun;Moon, Joo Hyun
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • 제18권2_spc호
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    • pp.247-260
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    • 2020
  • A multi-regression model was developed to estimate the decommissioning cost for Kori unit 1 using foreign nuclear power plant (NPP) decommissioning cost data. First, the decommissioning cost data were collected for 13 boiling water reactors and 16 pressurized water reactors and converted into the values as of November 2019. Then, for the regression model, the decommissioning cost was chosen as the dependent variable, and two variables were selected as independent variables: a contamination factor that was designed to reflect the operational characteristics of the decommissioned NPP and the decommissioning period. A statistical package in the R language was used to derive the regression model. Finally, the regression model was applied to estimate the decommissioning cost for Kori unit 1. The estimated decommissioning cost for Kori unit 1 was 663.40~928.32 million US dollars (782,812~1,095,418 million Korean won).

Lamb Production Costs: Analyses of Composition and Elasticities Analysis of Lamb Production Costs

  • Raineri, C.;Stivari, T.S.S.;Gameiro, A.H.
    • Asian-Australasian Journal of Animal Sciences
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    • 제28권8호
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    • pp.1209-1215
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    • 2015
  • Since lamb is a commodity, producers cannot control the price of the product they sell. Therefore, managing production costs is a necessity. We explored the study of elasticities as a tool for basing decision-making in sheep production, and aimed at investigating the composition and elasticities of lamb production costs, and their influence on the performance of the activity. A representative sheep production farm, designed in a panel meeting, was the base for calculation of lamb production cost. We then performed studies of: i) costs composition, and ii) cost elasticities for prices of inputs and for zootechnical indicators. Variable costs represented 64.15% of total cost, while 21.66% were represented by operational fixed costs, and 14.19% by the income of the factors. As for elasticities to input prices, the opportunity cost of land was the item to which production cost was more sensitive: a 1% increase in its price would cause a 0.2666% increase in lamb cost. Meanwhile, the impact of increasing any technical indicator was significantly higher than the impact of rising input prices. A 1% increase in weight at slaughter, for example, would reduce total cost in 0.91%. The greatest obstacle to economic viability of sheep production under the observed conditions is low technical efficiency. Increased production costs are more related to deficient zootechnical indexes than to high expenses.

A Study on the Usefulness and Cost Analysis of Busan Port Container Terminal by Time-Driven ABC (TDABC에 의한 부산항 컨테이너터미널 원가분석과 유용성에 관한 연구)

  • Ryu, Dong-Ha;Ahn, Ki-Myung;Hwang, Sung-Gu
    • Journal of Korea Port Economic Association
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    • 제30권3호
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    • pp.89-120
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    • 2014
  • The purpose of the study is to suggest a new approach to the terminal operators in order for them to efficiently control their operation cost and support the strategic decision making system and build a performance evaluation process through the systematic cost analysis approach. This study implemented terminal cost analysis based on the traditional cost system, ABC and TDABC and compared the results of each approach. Throughout the study, the usefulness of TDABC was proved in finding operational problems and suggesting countermeasures for improving cost effectiveness and minimizing unused cost.

A Study on Voice Communication over Data Communication Network (데이터 통신망에서 음성통신에 대한 연구)

  • 우홍체
    • Proceedings of the Korean Institute of Intelligent Systems Conference
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    • 한국퍼지및지능시스템학회 2000년도 추계학술대회 학술발표 논문집
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    • pp.471-475
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    • 2000
  • Voice and data are transmitted over a single packetized data communications network which is designed for data communications. The public switched telephone network for voice and the packet data network for data are merging into a single data network to get efficiency and to reduce operational cost. However, integrating voice and data transmission over a single data network is not easy because voice should be transmitted without delay but data should be transmitted without error. Advances in technology begin to overcome basic differences. Several integration methods in voice and data will be examined and reviewed here. Moreover, trends and problems on integration will be also discussed.

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AC-PDP Sustain Driver using Bidirectional Switches

  • Kang, Feel-Soon
    • Journal of Electrical Engineering and Technology
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    • 제6권1호
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    • pp.86-93
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    • 2011
  • To minimize the cost and power consumption of PDP TV, a practical sustain circuit topology is presented with an address-and-display-period-separated driving scheme. The proposed sustain driver employs bidirectional switches to reduce the number of components. Operational principles and corresponding features are illustrated and compared with the conventional approach. The valuable contributions of the proposed high-performing sustainer has been proven by computer-aided simulations and experiments by using a prototype equipped with 7.5-inch diagonal panel operated at 200 kHz switching frequency.

Profitability Evaluation System for Railway Transportation Plan (철도수송계획의 수익성 평가체계)

  • Kim, Dong-Hui;Hong, Sun-Heum
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 대한산업공학회/한국경영과학회 2004년도 춘계공동학술대회 논문집
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    • pp.211-214
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    • 2004
  • In railway system, the transportation plan corresponds to master plan for transport services. This service plan must be constructed to minimize operational cost or maximize revenue considering transportation demands and resource capacities in the operation company, and includes several sub-planning activities such as train operation frequency plan, train (schedule) plan, train capacity assignment plan, and rolling stock requirement plan. In this paper, we present profitability evaluation system for current transportation plan. The proposed system can be used for evaluating profitability by estimating train service revenue considering customer demands.

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Tool life in Metal Forming Processes (소성가공에 있어서의 금형수명)

  • 최재찬;김병민
    • Transactions of Materials Processing
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    • 제3권2호
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    • pp.147-155
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    • 1994
  • The service life of tools in metal forming technology is to a large extent limited by wear and fatigue fracture of the active elements. This presents a basic request for tool cost minimization and reduction of extensive machine down time, caused by premature tool failure. Currents developments are dominated by steps to reduce the causes of tool failure. A main problem of forming technology remains the insufficient reliability of tools due to a large and incalculable life time fluctuation. Only a systematic investigation of the failure mechanisms and operational loading of tools can lead to future improvements in tool layout, that is optimization of tool usage.

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Technology for Fatigue Life Prediction of Mechanical Components using Multibody Dynamics (다물체동력학을 이용한 기계 부품의 피로수명 예측 기술)

  • Han, Hyeong-Seok
    • 연구논문집
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    • 통권27호
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    • pp.47-55
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    • 1997
  • Fatigue life prediction of mechanical components is necessary to develop new products, which is very expensive and time-consuming. This paper reviews technologies proposed for computation of dynamic stress in mechanical components. The methods based on multibody dynamics are considering more real operational conditions than other methods. The technology for fatigue life prediction without the prototype for experiment results in cost and time saving. This technology can be applied to design of various mechanical components like carbody.

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