• 제목/요약/키워드: Reduction costs

검색결과 883건 처리시간 0.028초

Environmental awareness and economical profits of replacing gas turbines in gas compressor stations: A case study of Polkalleh station in Iran

  • Sadrnejad, Amin;Noorollahi, Younes;Sadrnejad, Tohid
    • Environmental Engineering Research
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    • 제21권2호
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    • pp.132-139
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    • 2016
  • In early 90s the worldwide awareness about the energy crisis and global warming had been increased and emission reduction (by improving energy efficiency), as well as increasing the capacity of clean and renewable energies, showed themselves as the most important steps towards the sustainable development approach. However, investigations on Iran's environmental situation show huge decline in recent decades and apparently there is no sense of urgency about these issues through the vision of Iranian politicians. In this article the idea of replacing the old gas turbines of Polkalleh natural gas compressor station - as one of the main compressor stations of Iran - with newer and more efficient gas turbines is evaluated, emphatically for reducing greenhouse gases emissions and their environmental costs and decreasing natural gas consumption as well. Clearly such idea is costly, but analyzing its economic impacts, huge declines in annual costs and greenhouse gases emissions can be seen as well. So an investment about $95 million can decrease 40% of Polkalleh compressor station annual costs, 25% of natural consumption and 30% of $CO_2$ and $NO_x$ emissions. Besides the simple payback period of this investment is about 2.5 years from the cut-expenses of annual costs.

원예시설의 에너지 부하패턴을 고려한 축열식 지열시스템 설계법에 관한 연구 (Design method of heat storage type ground source heat pump system considering energy load pattern of greenhouse)

  • 유민경;남유진;이광호
    • KIEAE Journal
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    • 제15권3호
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    • pp.57-63
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    • 2015
  • Purpose: Ground source heat pump system has been attracted in the horticulture industry for the reduction of energy costs and the increasing of farm income. Even though it has higher initial costs, if it uses in combination with heat storage, it is able to reduce the initial costs and operate efficiently. In order to have significant effect of heat storage type ground source heat pump system, it is required to design the capacity considering various conditions such as energy load pattern and operating schedule. Method: In this study, we have designed heat storage type ground source heat pump system in 5 cases by the operating schedule, and examined the system to find the most economic and having superb performance regarding the system COP(Coefficient of Performance) and energy consumption, using dynamic energy simulation, TRNSYS 17. Result: Conventional ground source heat pump system has lower energy consumption than heat storage type, but following the result of LCC(Life Cycle Cost) analysis, the heat storage type was more economic due to the initial costs. In addition, it has the most efficient performance and energy costs in the case of the smallest heat storage time.

A Resource Reduction Scheme with Low Migration Frequency for Virtual Machines on a Cloud Cluster

  • Kim, Changhyeon;Lee, Wonjoo;Jeon, Changho
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • 제7권6호
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    • pp.1398-1417
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    • 2013
  • A method is proposed to reduce excess resources from a virtual machine(VM) while avoiding subsequent migrations for a computer cluster that provides cloud service. The proposed scheme cuts down on the resources of a VM based on the probability that migration may occur after a reduction. First, it finds a VM that can be scaled down by analyzing the history of the resource usage. Then, the migration probability is calculated as a function of the VM resource usage trend and the trend error. Finally, the amount of resources needed to eliminate from an underutilized VM is determined such that the migration probability after the resource reduction is less than or equal to an acceptable migration probability. The acceptable migration probability, to be set by the cloud service provider, is a criterion to assign a weight to the resource reduction either to prevent VM migrations or to enhance VM utilization. The results of simulation show that the proposed scheme lowers migration frequency by 31.6~60.8% depending on the consistency of resource demand while losing VM utilization by 9.1~21.5% compared to other known approaches, such as the static and the prediction-based methods. It is also verified that the proposed scheme extends the elapsed time before the first occurrence of migration after resource reduction 1.1~2.3-fold. In addition, changes in migration frequency and VM utilization are analyzed with varying acceptable migration probabilities and the consistency of resource demand patterns. It is expected that the analysis results can help service providers choose a right value of the acceptable migration probability under various environments having different migration costs and operational costs.

급수지역 여건을 고려한 유수율 변동 분석 및 적정 유수율 제고 사업비 산정 모델 개발 (A study on the evaluation for variation of revenue water ratio considering water supply area conditions and the development of proper cost estimation model of project for improvement of revenue water ratio)

  • 권기원;형진석;김태현;박해금;오유진;구자용
    • 상하수도학회지
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    • 제37권6호
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    • pp.409-423
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    • 2023
  • In this study, we analyzed how the revenue water ratio(RWR) is affected by changes in conditions of the water supply area, such as the ratio of aging pipes, maintenance conditions, and revenue water. As a result of analyzing the impact of pipe aging and maintenance conditions on the RWR, it was confirmed that the RWR could be decreased if the pipe replacement project to improve the aging pipe ratio was not carried out and proper maintenance costs were not secured. It was also confirmed that an increase in the revenue water could be operated to facilitate the achievement of the project's target RWR. In contrast, a decrease in the revenue water due to a population reduction could affect the failure of the target RWR. In addition to analyzing the causes of variation in the RWR, the calculation of estimated project costs was considered by using leakage reduction instead of RWR from recent RWR improvement project cost data. From this analysis, it was reviewed whether the project costs planned to achieve the target RWR of the RWR improvement project in A city were appropriate. In conclusion, the RWR could be affected by variations in the ratio of aging pipes, maintenance conditions, and revenue water, and it was reasonable to consider not only the construction input but also the input related to RWR improvement, such as leakage reduction, when calculating the project cost.

의약분업의 비용-편익 분석 (Cost-benefit Analysis of Mandatory Prescription in Korea)

  • 김한중;박은철;강혜영;지영건
    • Journal of Preventive Medicine and Public Health
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    • 제33권4호
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    • pp.484-494
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    • 2000
  • Objective : To evaluate the relative benefits and the costs associated with the introduction of the new pharmaceutical provision called 'Mandatory Prescription System' which separates the role of physicians from that of pharmacists with respect to the prescription and dispensation of from the perspective of consumers (i.e., patients). Methods : The costs of the system were measured by considering both direct and indirect costs. Direct costs included additional payments for ambulatory care and dispensing fees that occurred under the new system. indirect costs consisted of transportation expenses and costs related to time spent for physician consultation, waiting for the prescriptions to be filled, and extra traveling. Benefits identified in this study were the reduction of drug misuse and overuse, and the overall decrease in drug consumption among the Korean population. Sensitivity analysis was peformed for the inclusion of benefits for outpatients of hospitals, price elasticity, and increased fees for established patients. Results : The net benefit was estimated to be about minus 1,862 billion won and the benefit-cost ratio was 0.478. This indicates that the costs of 'Mandatory Prescription' outweigh its benefits, relative to the previous system. The sensitivity analysis results for all the variables considered in this study consistently showed the benefit-cost ratio to be less than 1. Conclusion : The results of this study suggest that implementing Mandatory Prescription System in Korea might be inefficient from the consumer's perspective. The results of this study do not coincide with the results of previous studies, presumably because of the differences in study design and in which items of costs and benefits were considered.

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상황인식 기반 지능형 최적 경로계획 (Intelligent Optimal Route Planning Based on Context Awareness)

  • 이현정;장용식
    • Asia pacific journal of information systems
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    • 제19권2호
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    • pp.117-137
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    • 2009
  • Recently, intelligent traffic information systems have enabled people to forecast traffic conditions before hitting the road. These convenient systems operate on the basis of data reflecting current road and traffic conditions as well as distance-based data between locations. Thanks to the rapid development of ubiquitous computing, tremendous context data have become readily available making vehicle route planning easier than ever. Previous research in relation to optimization of vehicle route planning merely focused on finding the optimal distance between locations. Contexts reflecting the road and traffic conditions were then not seriously treated as a way to resolve the optimal routing problems based on distance-based route planning, because this kind of information does not have much significant impact on traffic routing until a a complex traffic situation arises. Further, it was also not easy to take into full account the traffic contexts for resolving optimal routing problems because predicting the dynamic traffic situations was regarded a daunting task. However, with rapid increase in traffic complexity the importance of developing contexts reflecting data related to moving costs has emerged. Hence, this research proposes a framework designed to resolve an optimal route planning problem by taking full account of additional moving cost such as road traffic cost and weather cost, among others. Recent technological development particularly in the ubiquitous computing environment has facilitated the collection of such data. This framework is based on the contexts of time, traffic, and environment, which addresses the following issues. First, we clarify and classify the diverse contexts that affect a vehicle's velocity and estimates the optimization of moving cost based on dynamic programming that accounts for the context cost according to the variance of contexts. Second, the velocity reduction rate is applied to find the optimal route (shortest path) using the context data on the current traffic condition. The velocity reduction rate infers to the degree of possible velocity including moving vehicles' considerable road and traffic contexts, indicating the statistical or experimental data. Knowledge generated in this papercan be referenced by several organizations which deal with road and traffic data. Third, in experimentation, we evaluate the effectiveness of the proposed context-based optimal route (shortest path) between locations by comparing it to the previously used distance-based shortest path. A vehicles' optimal route might change due to its diverse velocity caused by unexpected but potential dynamic situations depending on the road condition. This study includes such context variables as 'road congestion', 'work', 'accident', and 'weather' which can alter the traffic condition. The contexts can affect moving vehicle's velocity on the road. Since these context variables except for 'weather' are related to road conditions, relevant data were provided by the Korea Expressway Corporation. The 'weather'-related data were attained from the Korea Meteorological Administration. The aware contexts are classified contexts causing reduction of vehicles' velocity which determines the velocity reduction rate. To find the optimal route (shortest path), we introduced the velocity reduction rate in the context for calculating a vehicle's velocity reflecting composite contexts when one event synchronizes with another. We then proposed a context-based optimal route (shortest path) algorithm based on the dynamic programming. The algorithm is composed of three steps. In the first initialization step, departure and destination locations are given, and the path step is initialized as 0. In the second step, moving costs including composite contexts into account between locations on path are estimated using the velocity reduction rate by context as increasing path steps. In the third step, the optimal route (shortest path) is retrieved through back-tracking. In the provided research model, we designed a framework to account for context awareness, moving cost estimation (taking both composite and single contexts into account), and optimal route (shortest path) algorithm (based on dynamic programming). Through illustrative experimentation using the Wilcoxon signed rank test, we proved that context-based route planning is much more effective than distance-based route planning., In addition, we found that the optimal solution (shortest paths) through the distance-based route planning might not be optimized in real situation because road condition is very dynamic and unpredictable while affecting most vehicles' moving costs. For further study, while more information is needed for a more accurate estimation of moving vehicles' costs, this study still stands viable in the applications to reduce moving costs by effective route planning. For instance, it could be applied to deliverers' decision making to enhance their decision satisfaction when they meet unpredictable dynamic situations in moving vehicles on the road. Overall, we conclude that taking into account the contexts as a part of costs is a meaningful and sensible approach to in resolving the optimal route problem.

육상전력 사용에 따른 정박중인 선박의 $CO_2$ 배출 및 운항비용 절감에 관한 연구 (A Study on the Reduction of $CO_2$ Emissions and Operating Costs of the Ship in Port by Shore Electric Power)

  • 한원희;임경선
    • 해양환경안전학회지
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    • 제16권2호
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    • pp.229-234
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    • 2010
  • 최근 온실가스 감축을 위한 세계 각국의 노력이 다각도로 진행되고 있으며, 국제적인 협력 또한 시급히 요구되고 있다. 이러한 노력의 일환으로 해운 업계에서는 항내에서 유발되는 선박 기인 온실가스 배출량 중 탄소에 대한 배출량 감축과 선박운항 비용 절감을 위한 친환경 항만 체계 구축 방안이 활발히 논의되고 있다. 이 논문에서는 탄소 배출량 감축 및 친환경 항만 체계 구축의 기초 연구로 정박 중인 선박에 자체 생산 전력을 공급하는 대신 육상전력을 공급하는 방안을 모색하였다. 이를 위하여 실제 운항중인 목포해양대학교의 실습선 새누리호를 대상으로 정박 중인 선박이 육상전력을 사용함으로써 얻을 수 있는 환경적 비용적 효과에 관해 고찰하였다. 연구 결과 육상전력을 사용한 경우에 $CO_2$ 배출량은 약 32.5%가 감소되었고, 운항비용은 약 33%가 절감된 것으로 나타났다.

이상지질혈증 환자에게 사용되는 Rosuvastain과 Atorvastatin의 경제성 평가 (Economic Evaluation of Rosuvastatin and Atorvastatin for the Treatment of Dyslipidemia from a Korean Health System Perspective)

  • 서성환;정창희;홍순준;김중선;송병주;손현순;최성희
    • 지질동맥경화학회지
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    • 제5권1호
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    • pp.61-77
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    • 2016
  • Objective: This study aims to analyze cost-effectiveness of two most-commonly used statins from the perspective of the Korean national health system. Methods: The scope of the analysis included rosuvastatin (5 mg, 10 mg, and 20 mg) and atorvastatin (10 mg, 20 mg, 40 mg, and 80 mg). Effectiveness was defined as percentage (%) and absolute (mg/dL) reductions of low-density lipoprotein cholesterol (LDL-C) from the baseline. They were derived from published randomized controlled studies for rosuvastatin and atorvastatin. Effectiveness was defined as reductions in LDL-C levels per mg dose of the drugs. The annual direct medical costs including drug acquisition costs and monitoring costs over the one-year time horizon were calculated for each alternative. The average cost-effectiveness ratios (ACERs) and incremental cost-effectiveness ratios (ICERs) for each statin dose were calculated. Results: The ACERs for all doses of rosuvastatin (5 mg, 10 mg, and 20 mg) were lower than those for all doses of atorvastatin (10 mg, 20 mg, 40 mg, and 80 mg). Rosuvastatin 10 mg was the most cost-effective statin for LDL-C reduction. In cost-effectiveness analyses for corresponding doses of rosuvastatin and atorvastatin, rosuvastatin was the superior strategy which suggests both higher effectiveness and lower costs than atorvastatin. However, we have to consider this analysis is highly influenced by current price of statins in each market. Conclusion: For reduction of LDL-C levels in Korean patients with dyslipidemia, rosuvastatin 10mg is the most cost-effective statin in the current Korean market.

병원서비스별 원가분석모형의 개발과 적용 (Development of a Hospital Service-based Costing System and Its Application)

  • 박하영
    • 보건행정학회지
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    • 제5권2호
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    • pp.35-69
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    • 1995
  • The managerial environment of hospitals in Korea characterized by low levels of medical insurance fees is worsening by increasing government regulations as to the utilization of medical services, rising costs of labor, material, and medical equipments, growing patient expectations concerning the quality of services, and escalating competitions among large hospitals in the market. Hospitals should seek for their survival strategies in this harsh environment and they should have information about costs of their products in doing so. However, it has not been available due to the complexity of the production process of hospital services. The objectives of this study were to develop a service-based cost accounting model and to apply the developed model to a study hospital to obtain cost information of hospital services. A model commonly used for the job-order product cost accounting in the manufacturing industry was modified for the use in hospitals in Korea. Actual costs, instead of standard costs, incurred to produce a unit of services during a given period of time were estimated in the model. Data required to implement the model included financial information, statistics for the allocation of supportive cost center costs to final cost centers, statistics for the allocation of final cost center costs to services, and the volume of each services charged to patients during a study period. The model was executed using data of a university teaching hospital located in Seoul for the fiscal year 1992. Data for financial information, allocation statistics fo supportive service costs, and the volume of services, most of them in electronic form, were available to the study. Data for allocation statistics of final cost center costs were collected in the study. There were 15 types of evaluation and management service, 2, 923 types of technical service, and 2, 608 types of drug and material service charged to patients in the study hospital during the fiscal year 1992. Labor costs of each of seven types of pesonnel, material costs of 611 types of drugs and materials, and depreciation costs of 212 types of medical equipments, miscellaneous costs, and indirect costs incurred in producing a unit of each services were estimated. Medical insurance fees for basic services such as evaluation and management of inpatients and outpatients, injection, and filling prescriptions, and for operating procedures were found to be set lower than costs. Infrequent services which use expensive medical equipments showed negative revenuse as well. On the other hand, fees for services not covered by the insurance such as CT, MRI and Sonogram, and for laboratory tests were higher than costs. This study has a significance in making it possible for a hospital to obtain cost information for all types of services which produced income based on all types of expenses incurred during a given period of time. This information can assist the management of a hospital in finding an effective cost reduction strategy, an efficient service-mix strategy under a given fee structure, and an optimum strategy for within-hospital resource allocations.

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서울의 대중교통체계 개편에 따른 시내버스업체의 생산성 변화 (사고비용을 고려한 자료포락분석기법을 이용하여) (Productivity Changes by Public Transport Reforms in the Seoul's Urban Bus Industry (Using Data Envelopment Analysis with Consideration of Accident Costs))

  • 오미영;김성수
    • 대한교통학회지
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    • 제26권4호
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    • pp.77-86
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    • 2008
  • 서울의 대중교통체계 개편에 따른 시내버스업체의 생산성 변화를 사고비용 고려여부에 따라 비교분석하였다. 사고비용과 같은 유해한 산출물을 고려하면서 공공기관의 생산성 분석에 적합한 자료포락분석기법의 방향거리함수를 사용하였으며, 그 값을 맘퀴스트 루엔버거 생산성 지수에 적용하였다. 시내버스업체는 운전, 정비, 관리, 차량, 연료의 투입물을 사용하여, 운행거리, 승객수 및 사고비용을 생산하는 기업형태로 상정하였다. 분석결과 사고비용 고려여부와 상관없이 생산성은 약간 증가한 것으로 나타났으며, 사고비용을 고려했을 때가 제외했을 때보다 약간 더 증가한 것으로 나타났다. 이는 시간의 흐름에 따라 운행거리와 승객 수에 대한 투입물의 사용이 줄어들었을 뿐만 아니라 그 이상으로 안전성과 관련한 서비스가 향상되었음을 의미한다. 또한 개편 분야별 생산성 변화에 미친 영향을 분석해본 결과, 운행속도 증가와 승객 수 증가가 생산성 증가에 가장 영향을 미친 것으로 나타났다. 이는 중앙버스전용차로 설치와 대중교통통합요금거리비례제 도입의 결과를 반영하는 것으로 이들이 시간의 흐름에 따라 투입물을 감소시키면서 사고비용을 줄이는데 효과적이었다고 볼 수 있다. 다만 준공영제를 포함한 운영체계의 개편은 생산성 증가와는 관련은 있었으나 큰 영향을 미치지는 못하였다.