• Title/Summary/Keyword: efficiency Analysis

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A Study on the Efficiency Analysis of Global Line Service (글로벌선사의 운영성과 향상을 위한 항로의 효율성 분석)

  • Shin, Chnag-Hoon;Choi, Min-Seung;Song, Jae-Young
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • v.29 no.1
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    • pp.473-478
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    • 2005
  • This paper presents a approach to the measurement of efficiency which is trunk route of global liner. Data evelopment analysis(DEA), as it is called, has particular applicability in the service sector. Applying mathematical programming techniques, DEA enables relative efficiency ratings to be derived within a set of analysed units(line services). This paper investigates the efficiency employing DEA Model of line service classified into route(ex. America-asia line, Europe-asia line, Pendulum line etc). Result of this paper, suggests to some plan for improving the performance in the side of operating global liner.

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A Simulation based Study on the Economical Operating Strategies for a Residential Fuel Cell System (시뮬레이션 기반 가정용 연료전지 시스템의 경제적 운전전략에 관한 연구)

  • Hwang, Su-Young;Kim, Min-Jin;Lee, Jin-Ho;Lee, Won-Yong
    • Journal of Hydrogen and New Energy
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    • v.20 no.2
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    • pp.104-115
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    • 2009
  • In case of residential fuel cell system, it is significant to stably supply heat and power to a house with high efficiency and low cost for the successful commercialization. In this paper, the control strategy analysis has been performed to minimize the total cost including capital and operating cost of the residential fuel cell system. The proposed analysis methodology is based on the simulator including the efficiency models as well as the cost data for fuel cell components. The load control strategy is the key factor to decide the system efficiency and thus the cost analysis is performed when the fuel cell system is operated for several different load control logics. Additionally, annual efficiency of the system based on the seasonal load data is calculated since system efficiency is changeable according to the electric and heat demand change. As a result, the hybrid load control combined electricity oriented control and heat oriented control has the most economical operation.

Comparing the Efficiency of Public Libraries (공공도서관의 효율성 비교 분석 -서울시 및 6대 광역시의 102개 공공도서관을 대상으로 -)

  • Kim, Sun-Ae
    • Journal of the Korean Society for Library and Information Science
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    • v.41 no.2
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    • pp.237-256
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    • 2007
  • This study examined DEA(Data Envelopment Analysis) and how it measures the efficiency of library units. DEA is a useful nonparametric method to evaluate the relative efficiency of a set of decision making units(DMUs) with multiple inputs and outputs. This study evaluated 102 different public libraries utilizing 4 inputs and 4 outputs focussing on the year 2005. For inefficient libraries, the study analysed the potential improvement and the source of inefficiency comparing the peer groups. The result of this study shows that efficiency of public libraries varies in different localities and forms of operation.

Measuring the Efficiency in Korean Railway Transport using Data Envelopment Analysis (자료포락분석 기법을 이용한 우리나라 철도수송의 효율성 측정)

  • Kim, Hyun-Woong;Kook, Kwang-Ho;Moon, Dae-Seop;Lee, Jin-Sun
    • Journal of the Korean Society for Railway
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    • v.12 no.4
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    • pp.542-547
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    • 2009
  • The objective of this paper is to measure the relative technical efficiency of Korean railway transport service. Previous studies on the efficiency in Korean railway service have carried out before the structural reform of Korean railway industry in 2004, whereas this study used the latest data which reflected the impact of reform. We analyzed the efficiency in Korean railway transport by means of measuring the technical efficiencies of other countries, these were estimated with data envelopment analysis. Using data from 22 railway operators over the period $2000{\sim}2006$, the results indicate that the Korean railway transport has been operated efficiently as compared with others.

A decision support system (DSS) for construction risk efficiency in Taiwan

  • Tsai, Tsung-Chieh;Li, Hsiang-Wen
    • Smart Structures and Systems
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    • v.21 no.2
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    • pp.249-255
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    • 2018
  • Many studies in risk management have been focused on management process, contract relation, and risk analysis in the past decade, but very few studies have addressed project risks from the perspective of risk efficiency. This study started with using Fault Tree Analysis to develop a framework for the decision-making support system of risk management from the perspective of risk efficiency, in order for the support system to find risk strategies of optimal combination for the project manager by the trade-off between project risk and cost of project strategies. Comprehensive and realistic risk strategies must strive for optimal decisions that minimize project risks and risk strategies cost while addressing important data such as risk causes, risk probability, risk impact and risk strategies cost. The risk management in the construction phase of building projects in Taiwan upon important data has been analyzed, that provided the data for support system to include 247 risk causes. Then, 17 risk causes were extracted to demonstrates the decision-making support system of risk management from the perspective of risk efficiency in building project of Taiwan which could reach better combination type of risk strategies for the project manager by the trade-off between risk cost and project risk.

Evaluation of Efficiency on Informatization level of Container Terminal (컨테이너 터미널 정보화수준에 관한 효율성 평가)

  • Shin, Jae-Young;Choi, Bong-Hwan;Yang, Yun-Ok;Shin, Chang-Hoon
    • Proceedings of the Korean Institute of Navigation and Port Research Conference
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    • 2009.06a
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    • pp.147-148
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    • 2009
  • Today, overall industry have been operated on the basis of information technology and have been rised that expectation and investment on it. The distribution industry have growing up importance of integrated material handling information network, the information investment have increase to efficient operate. however, Most efficiency analysis has not been thoroughgoing enough any research that effect on informatization level about the efficiency. The paper describes the evaluation of informatization level of importance is presented to efficient operate in a container terminal, the relative efficiency on informatization level is measured using Data Envelopment Analysis.

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An Analysis of the Efficiency of the Global Logistics Industry with Data Envelopment Analysis and a Tobit Model (세계 물류산업의 효율성에 관한 연구)

  • Park, Woo-Ram;Kwon, Oh-Kyoung;Tongzon, Jose
    • Journal of Korean Society of Transportation
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    • v.26 no.5
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    • pp.41-49
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    • 2008
  • According to the demand for services. a single point contract between a user and provider spreads over the industry, and the relationship between them is a main issue. The user wants to make a deal with the contributor which can provide the effective services to the user. This study is to estimate the efficiency of global logistics industry with Data Envelopment Analysis, by nations from 2001 to 2005. Furthermore, it tries to estimate the inefficiency affected by macro factors, and proves the association between them using Tobit model. Global logistics industry has made growth both externally and internally more than doubled for the last 5years. Technical inefficiency of global logistics industry is more influenced by pure technical inefficiency than inefficiency of scale. Therefore technical efficiency can be increased by decreasing pure technical inefficiency. Through this study, it found that the logistics industry got influenced to its efficiency by high price of oil, and courier and transportation service market is formed stably. Furthermore, it advocates policy planners to consider effectiveness and clearness of policy which influence to inefficiency of logistics industry. Also, it found that labor and financial support can give critical effect.

Application of CFD in The Analysis of Aerodynamic Characteristics for Aircraft Propellers (전산유체역학을 이용한 항공기 프로펠러 공력특성 연구)

  • Cho, Kyuchul;Kim, Hyojin;Park, Il-Ju;Jang, Sungbok
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.40 no.11
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    • pp.917-926
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    • 2012
  • The analysis of aerodynamic characteristics for aircraft propellers is studied to develop high efficiency composite propellers. It is to verify the accuracy and reliability of predicting the efficiency characteristics of aircraft propellers by applying nonlinear numerical analysis. The numerical simulation method incorporated the CFD code, which is based on RANS (Reynolds Averaged Navier-Stocks) equation. The study includes a comparative analysis between the numerical simulation results and the wind tunnel test results of the full-scale aircraft propeller. The comparison shows that thrust and power coefficients of the propeller calculated by nonlinear numerical analysis are higher than those based on the results generated from the wind tunnel test. The efficiency of the propeller calculated by numerical analysis matches closely to the efficiency based on the wind tunnel test results. The verification results are analyzed, then, will be used in optimizing the design and manufacture of the subject aircraft propeller studied.

Case Study on the Jeollabuk-do Local Water Supply Efficiency by using DEA and Malmquist Index (DEA 및 맘퀴스트 지수를 이용한 전라북도 지방상수도 효율성 사례분석)

  • Choi, Kyoung-Ho;Cho, Jung-Keun
    • Journal of Digital Convergence
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    • v.12 no.12
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    • pp.571-580
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    • 2014
  • Korea's water supply efficiency is low, due to weak industrial structure, such as small scale, regional disparities in the management and services, unreasonable problem in a use and management of interregional water resources. This study investigated changes in the productivity of Jeollabuk-do local water supply service by using analysis of efficiency by data envelopment analysis and Malmquist Index Analysis. As a result, 6 office is showed that the value of scale efficiency is 1 and productivity index per gun in mainly seemed below average. Therefore these offices should strive to increase their productivity. This study is differentiated from earlier studies in the aspect of measuring change of productivity by not only DEA but also Malmquist productivity analysis. Therefore it will contribute to increase productivity of water supply in Jeollabuk-do.

Analysis of Operational Efficiency of Military Department of University Using Data Envelopment Analysis Method (자료포락분석법을 활용한 일반대학 군사학과의 운영 효율성 분석)

  • Young-Min Bae;Sweng-Kyu Lee
    • Convergence Security Journal
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    • v.23 no.2
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    • pp.95-102
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    • 2023
  • The purpose of this paper was to confirm the operational level of the military department of universities, which plays a key role in the officer training process, through empirical research and confirm meaningful results for improvement. There are 11 university military departments operated through the Army, agreements, and semi-agreement, and the Data Envelopment Analysis (DEA) was applied from the perspective of resource input and performance for each university's military department operation to analyze relative efficiency and confirm specific directions for improvement. As a result of operational efficiency analysis, 6 DMUs (Decsision Making Unit) were found to be efficient in the BCC model out of 11 DMUs, and the evaluation results could be confirmed through classification of efficient and inefficient groups through data capture analysis. This paper may be of practical value in that it checks the efficiency of the comparative university military departments and confirms specific information for development through the DEA-Additive model that reflects several evaluation factors at once. Through this, the operators of each university's military department are admitted.