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An International Comparison of R&D Efficiency: DEA Approach

  • Lee, Hak-Yeon;Park, Yong-Tae
    • 기술혁신연구
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    • 제13권2호
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    • pp.207-222
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    • 2005
  • A prerequisite for making R&D more productive is to able to measure its productivity. Most of the previous studies on this topic have attempted to measure R&D productivity at the firm or industry levels. In this study, however, R&D productivity is measured at the national level to provide R&D policy implications, particularly for Asian countries. Contrary to the previous studies where total factor productivity was adopted, this study employs the data envelopment analysis (DEA) approach to measure R&D productivity. DEA is a multi-factor productivity analysis model for measuring the relative efficiency of each Decision Making Unit (DMU). In addition to the basic DEA model that includes all inputs and outputs, five additional models are constructed by combining single input with all outputs and single output with all inputs in order to measure specialized R&D efficiency. In this study, the twenty-seven countries are classified into four clusters based on the output-specialized R&D efficiency: inventors, merchandisers, academicians, and duds. Then, the characteristics of the Asian countries with respect to R&D efficiency are identified. It is found that Singapore ranks high in total efficiency, and Japan in patent-oriented efficiency. Meanwhile, China, Korea, and Taiwan are found to be relatively inefficient in R&D. We expect that the findings from this study will be able to provide directions for R&D policy-making of the Asian countries.

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

  • 신창훈;최민승;송재영
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2005년도 춘계학술대회 논문집
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    • pp.473-478
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    • 2005
  • 최근의 컨테이너물동량 증가는 선사간 경쟁의 심화를 유발하였고 이는 개별 선사들의 채산성 악화를 초래하였다. 따라서 운항선사들은 노선에 투입되는 자사 선박들에 대해서 운항효율성을 분석하고 대응방안을 강구할 필요성이 대두되고 있다. 이러한 배경에서 출발한 본 연구는 선사측면에서의 운항효율성을 분석하고 도출된 결과를 바탕으로 효율성을 향상시킬 수 있는 방안을 제시하고자 한다. 효율성분석을 하기 위해서 본 연구에서는, 운항선사의 실제 운항자료를 바탕으로 항차를 의사결정단위로 하여 비교적 객관적이고 상대적인 효율성을 파악할 수 있는 DEA모형을 이용하여 분석을 수행하였다. 그리고 효율성 분석결과를 바탕으로 운항선사의 운영측면에서 전체적인 효율성을 높이는 방안을 모색해 보고자 한다.

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S-CODE: A Subdivision Based Coding System for CAD Models

  • Takarada, Yosuke;Takeuchi, Shingo;Kawano, Isao;Hotta, Jun;Suzuki, Hiromasa
    • International Journal of CAD/CAM
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    • 제3권1_2호
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    • pp.97-109
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    • 2003
  • A large scale polygon models are often used to approximately represent 3D CAD models in Digital Engineering environment such as DMU (Digital Mockups) and network based collaborative design. However, they are not suitable for distribution on the network and for interactive rendering. We introduce a new coding system based on subdivision schemes called S-CODE system. In this system, it is possible to highly compress the model with sufficient accuracy and to view the model efficiently in a level of detail (LOD) fashion. The method is based on subdivision surface fitting by which a subdivision surface and curves which approximate a face of a CAD model are generated. We also apply a subdivision method to analytic surfaces such as conical and cylindrical surfaces. A prototype system is developed and used for evaluation with reasonably complicated data. The results show that the method is useful as a CAD data coding system.

유럽 규격을 적용한 디젤동차 대차프레임의 정적 및 피로강도 평가 (Evaluation of static and fatigue strength applying European standard for the bogie frame of Diesel Multiple Unit)

  • 김우진;송시엽;박근수;박형순
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2007년도 추계학술대회 논문집
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    • pp.801-808
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    • 2007
  • Rotem Company has designed and manufactured bogie for Diesel Multiple Unit (DMU) according to the European standard UIC615-4, which si normally used for designing bogie frame. Because the countries located in Middle East do not have their own regulations for bogie design, most of running bogies in Middle East are designed by using European standard UIC615-4. UIC615-4 specifies the loads that bogie frame should withstand, indicates the way of material data to be used and the principles to be during verification by analysis and test. The bogie frame depends on the load conditions and magnitudes which are subjected to during service and characteristics of materials they are manufactured from. From the above reason, Rotem Company has performed Finite Element Analysis and load tests on the bogie frame according to UIC615-4. This research contains the results obtained by the analysis and the load tests. Also, this research verifies that the bogie frame has a static strength and fatigue strength. The analysis is carried out using I-DEAS 12 NX Series and specially designed test jigs and equipment are used for the load tests.

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국내 중소건설업체의 효율성 평가에 관한 연구 (A Study on the Evaluation of Efficiency in the Korean Small and Medium sized Construction Firms)

  • 김혁;유한주;송광석
    • 품질경영학회지
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    • 제38권3호
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    • pp.463-474
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    • 2010
  • In this study, we evaluate the efficiency of Construction Industry using Data Envelopment Analysis(DEA). Since the Construction Industry has been traditionally operated through competition, it is important to measure the efficiency. In this paper, we empirically analyze the Efficiency of the 50 Korean Construction Industry. In detail, we used the scale of efficiency in order that efficiency cannot be affected by the total technical efficiency of each company and the scale of DMU by applying CCR or BBC model. Also, we analyzed the changes of measurement DEA model score. we adopted the basic DEA, RTS Region and MPSS(Most Productive Scale Size) method which are combined with efficiency measurement model in order to analyze the operational status. Furthermore, by complementing the shortfalls of the scale efficiency value of the DEA Model, RTS Region Model can be recommended to be appropriate in the evaluation of ideal input/output Quantity. In particular, input variables are total assets, construction capacity, the technical staff and output variables are sales volume, operating income. The result of RTS Region and MPSS shows that 9 DMUs of the efficiency frontier in the Construction Industry are analyzed to be relatively efficient DMUs, and 41 DMUs are analyzed to be inefficient DMUs, and finally inefficient DMUs are separated with Region 1 and Region 6.

DEA 모형을 이용한 세계 주요 항만의 효율성 평가 (An Empirical Study on the Efficiency of Major Container Ports With DEA Model)

  • 송재영;신창훈
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2004년도 춘계학술대회 논문집
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    • pp.351-356
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    • 2004
  • 부산항은 동북아시아의 급속한 성장과 더불어 지속적인 성장을 해오고 있으며, 향후 이러한 지속적인 성장을 유지하기 위해 정부의 집중 투자 및 정책 지원이 이루어지고 있다. 본 연구는 부산항을 포함한 세계 주요 컨테이너 항만들의 효율성을 DEA(Data Envelopment Analysis)모형을 통해 상대적으로 분석함으로써, 부산항의 현재 위치와 더 효율적인 항만이 되기 위해 Benchmarking 해야할 대상을 구체화 한 것이다. 또한, 본 연구에서는 일정시점의 효율성 분석이 아닌 1995년∼2001년까지 7개년 동안의 효율성을 시계열적으로 분석함으로써 각 항만의 효율성 변화를 살펴볼 것이며 이를 통해서 보다 유효한 효율성 분석 결과를 제시하고자 한다.

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철도차량 운전실제어대 설계기준 마련 연구 (study of standardization on the rollingstock's operational control box)

  • 임재은;정도원;김치태
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2008년도 춘계학술대회 논문집
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    • pp.2139-2144
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    • 2008
  • There are eight kinds of railroad vehicles such as KTX, PP(Push-Pull), NEL(New Electric Locomotive), EL(Electric Locomotive), DL(Diesel Locomotive), CDC(Commuter's Diesel Car), VVVF(Variable Voltage Variable Frequency) and Resistance Control Car that Korail corporation presently runs, and a variety of vehicles just like EMU(Electric Multiple Unit) and DMU(Diesel Multiple Unit) currently developed and accepted are running in the near future. However, There is still no design standard of the control stand of cockpit and the same compatibility of forms and control unit arrangements for locomotive engineers because no one has tried to approach in an ergonomic way. It can cause Locomotive engineers to make errors using the machinery. when the new vehicles are adopted, The efficiency of operation will quite fall down due to the separate training of the engineers. Therefore, We'd like to improve the accuracy of manipulating the machinery used by the engineers at all times according to the design standard of ergonomic technology and safety engineering and increase the operational efficiency and the safety of railroad vehicles in order to handle the problems as quickly as we can in an emergent situation.

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전기동차와 디젤동차에서의 TCP/IP운용을 위한 PoE*의 사용에 의한 안전성 방안 (TCP/IP for safety operation for EMU** and DMU*** Trains by PoE)

  • 홍선호;하재호;김영태
    • 한국철도학회:학술대회논문집
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    • 한국철도학회 2009년도 춘계학술대회 논문집
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    • pp.848-854
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    • 2009
  • Of the rapid development of modem civilization development is one of the IT industry. The Network is the root of the discrete industry. Most of the Protocol is used by LAN and the TCP / IP. Slowly in the railway operation of this Network is being applied. It also used to train and they are operated. The concept of the road, the Network TCP / IP using a non-Star structure of the Main Unit and the Bus Network is designed to structure consists of the Network. This structure is a simplified DATA. Data of complex operations is easy to feel the speed limit is. In addition, all devices must be independent to the operating system with the ability to manage the operation and stability in terms of exactly how the transmission of Data is gonna work pass. And transmission occurs in the middle of the Noise and the device is available to manage the power. Noise in the power of the railway to ensure the efficient transfer of Data is by blocking. Also, by presenting the entire system's operational safety should be guaranteed the safety of the railway.

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최적화를 통한 토크 컨버터 댐퍼 스프링 설계 자동화에 관한 연구 (Design Automization for Torque Converter Damper Spring Using Optimization)

  • 박병건;황길언;김재정;장재덕
    • 한국CDE학회논문집
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    • 제12권3호
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    • pp.163-170
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    • 2007
  • A torque converter, connected to a transmission/transaxle input shaft, connects, multiplies and interrupts the flow of engine torque into the transmission. Damper springs are usually equipped in a torque converter to convert stably the torque power supplied from engine. Damper Springs generally have the most flexible design variables among vehicle transmission parts, so that they could be effective design factors to improve the entire vehicle's performance. Damper spring, however, has geometric complexity after it equipped in a torque converter. For that reason, modeling a damper spring requires expert's knowledge to determine many design parameters and satisfy the functional requirements at the same time. In this paper, we introduce an optimum design method applied in detailed-design stage to reduce design process and financial loss caused by adequate design. Many design variables have to be classified and structuralized for Optimization. This also could make designer concentrate on functional requirements of damper spring, not on design possibility. In addition, modeling an assembled spring has technical restriction with primitives of the current major CAD solutions because of complexity of assembled spring shape. Thus, one of modeling solution presented in this paper since detailed and exact modeling is important for CAE or DMU.

Trends in Indian Private Sector Bank Efficiency: Non-Stochastic Frontier DEA Window Analysis Approach

  • KUMAR, Ashish;ANAND, Nakul;BATRA, Vikas
    • The Journal of Asian Finance, Economics and Business
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    • 제7권10호
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    • pp.729-740
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    • 2020
  • The study examines the efficiency of private sector banks in India with the help of Window DEA (Data Envelopment Analysis) for a period from 2005 to 2017. With a window of three years, the period was divided into 11 windows. The study outcomes show that 59.9% of all private sector banks in India operate at more than 0.9 level of efficiency, and there are only three occasions when banks were operating at the efficiency value between 0.6 to 0.7. Further, the consistency in the efficiency scores of the banks has also been analyzed using an efficiency mapping matrix, and the mean efficiency score of the bank in each window is studied. The score of standard deviation was interpreted accordingly for these banks. Banks that are showing the highest efficiency scores also have a higher variance of efficiency scores. There was no bank identified in the matrix that promises high-efficiency ratings with low variability. The study concludes that the analysis of the efficiency mapping matrix indicates that, as a DMU escalates in the efficiency scores, the standard deviation reflecting the risk in overall efficiency scores also tends to rise. The findings complement the concept of higher risk to higher return or greater efficiency.