• 제목/요약/키워드: DEA Method

검색결과 486건 처리시간 0.021초

DEA 기법을 이용한 효율적 포트폴리오 구성 방안 (An Efficient Portfolio Selection Methodology using DEA Approach)

  • 손민;신현준
    • 한국산학기술학회논문지
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    • 제13권4호
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    • pp.1551-1556
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    • 2012
  • 본 연구에서는 KOSPI에 상장된 기업을 대상으로 기업의 효율성을 고려하여 포트폴리오를 구성하는 방안을 제시한다. 이를 위해 한국거래소(KRX)에서 구분하는 산업 업종별로 DEA(Data Envelopment Analysis) 기법을 이용하여 기업 효율성 분석을 실시하고 효율성이 우수한 기업들을 대상으로 마코위츠 모형을 통해 포트폴리오를 구성한다. 본 연구에서 제안한 포트폴리오 구성 방안의 성능 실험을 위해 KOSPI에 상장된 약 600개의 기업의 주식을 대상으로 4년 (2007~2010) 동안 매해 포트폴리오를 구성하였고 각각의 포트폴리오 수익률을 경영 효율성을 고려하지 않고 구성한 포트폴리오 및 시장 수익률과의 비교 분석을 통해 그 우수성을 입증하였다.

자기 조립법을 이용한 BaFe12O_19의 제조 및 자성 특성에 대한 연구 (A Study on Magnetic Properties of BaFe12O_19 Fabricated by Self-assembly Method)

  • 최문희;유지훈;김동환;이혜문;김수민;김양도
    • 한국분말재료학회지
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    • 제16권6호
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    • pp.410-415
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    • 2009
  • Hexagonal barium ferrite ($BaFe_{12}O_{19}$) nano-particles have been successfully synthesised using selfassembly method. Diethyleneamine (DEA) surfactant was used to fabricate the micelle structure of Ba-DEA complex under various DEA concentrations. $BaFe_{12}O_{19}$ powders were synthesized with addition Fe ions to Ba-DEA complex and then heat treated at temperature range of 800-1000${\circ}C$. The molar ratio of Ba/DEA and heat-treatment temperature significantly affected the magnetic properties and morphology of $BaFe_{12}O_{19}$ powders. $BaFe_{12}O_{19}$ powders synthesized with Ba/DEA molar ratio of 1 and heat-treated at 1000${\circ}C$ for 1 hour showed the coercive forces (iHc) of 4.84 kOe with average crystal size of about 200 nm.

자기 조립 전구체를 이용한 초음파 분무 열분해 공정으로 제조한 BaFe12O19의 자기적 특성에 대한 연구 (A study on Magnetic Properties of BaFe12O19 Fabricated by Ultrasonic Spray-pyrolysis Process Using Self-Assembly Method)

  • 최문희;유지훈;김동환;정국채;김양도
    • 한국분말재료학회지
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    • 제17권4호
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    • pp.263-269
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    • 2010
  • Hexagonal barium ferrite ($BaFe_{12}O_{19}$) nano-particles have been successfully fabricated by spraypylorysis process. $BaFe_{12}O_{19}$ precursor solutions were synthesized by self-assembly method. Diethyleneamine (DEA) surfactant was used to fabricate the micelle structure of Ba-DEA complex under various DEA concentrations. $BaFe_{12}O_{19}$ powders were synthesized with addition of Fe ions to Ba-DEA complex and then fabricated $BaFe_{12}O_{19}$ powders by spray-pyrolysis process at the temperature range of $800{\sim}1000^{\circ}C$. The molar ratio of Ba/DEA and heat-treatment temperatures significantly affected the magnetic properties and morphology of $BaFe_{12}O_{19}$ powders. $BaFe_{12}O_{19}$ powders synthesized with Ba/DEA molar ratio of 1 and heat-treated at $900^{\circ}C$ showed the coercive forces (iHc) of 4.2 kOe with average crystal size of about 100 nm.

DEA분석 기법을 이용한 안전관리체제 운영효율성 분석 (An Analysis on the Operation Efficiency of Safety Management System using DEA Method)

  • 양형선;김철승;노창균
    • 해양환경안전학회지
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    • 제13권2호
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    • pp.141-146
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    • 2007
  • 본 연구에서는 국내 해운회사의 안전관리를 위한 여러 가지 투입요소와 산출요소들에 대한 자료를 설문조사하고, 각 해운회사간의 안전관리체제 이행에 따른 효율성을 DEA 분석법을 사용하여 분석하였다. 1998년$\sim$2004년까지 각 해운회사의 안전관리체체의 운영효율성을 DEA 모형으로 분석한 결과, 효율성 평균지수가 매년 감소하는 추세를 나타내었다. 효율성 평균지수가 매년 낮아지는 경향을 보이는 이유는 해양사고 건수, PSC지적 건수, 선박보험료, P&I 보험료는 매 년 감소하는 것에 비해 선박수리비, 선용품비와 선박 불가동일수는 매년 감소하지 않고 오히려 증가하는 경향을 보이고 있는 것이 주요한 원인으로 분석되었다.

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DEA와 Worst Practice DEA를 이용한 정보통신기업의 신용위험평가

  • 한국정보시스템학회
    • 한국정보시스템학회:학술대회논문집
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    • 한국정보시스템학회 2005년도 추계학술대회 발표 논문집
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    • pp.334-346
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    • 2005
  • The purpose of this paper is to introduce the concept of worst practice DEA, which aims at identifying worst performers by placing them on the efficient frontier. This is particularly relevant for our application to credit risk evaluation, but this also has general relevance since the worst performers are where the largest improvement potential can be found. The paper also proposes to use a layering technique instead of the traditional cut-off point approach, since this enables incorporation of risk attitudes and risk-based pricing. Finally, it is shown how the use of a combination of normal and worst practice DEA models enable detection of self-identifiers. The results of the empirical application on credit risk evaluation validate the method which is proposed in this paper.

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DEA를 이용한 서비스효율성 측정에 관한 연구 - 국내 5개 시중은행의 서비스품질지수를 중심으로 - (A Study on the Measurement of Service Efficiency using DEA - Focused on the SQI of Five Domestic Banks in Korea -)

  • 김진왕;유한주;송광석
    • 품질경영학회지
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    • 제37권1호
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    • pp.80-90
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    • 2009
  • Nowadays, there are many companies which employ the SQI measurement to assess service quality. The purpose of this study is to measure the service efficiency for Bank Industry. In this paper, we tried to measure the efficiency of service quality and overall customer satisfaction by using Data Envelopment Analysis(DEA). Rather than using the usual method of converting the Service Quality Index(SQI) into mean value, we applied CCR/BCC models in DEA to service quality efficiency. Also, DEA/PS Model is recommended as appropriate model for evaluating service efficiency by complementing the shortfalls of the weighted value of DEA Model. In this study, six dimensions of service quality were considered as input variables and output variables(overall customer satisfaction, reusing intention, and word of mouth). The result of this study statistically verifies that 5 DMUs are relatively efficient, and intensive activities for service efficiency are needed for 20 sample branches. Managerial implications based on the analysis were suggested.

DEA기반 순위선정 절차를 활용한 주력전차의 기술예측방법 비교연구 (A Comparative Study of Technological Forecasting Methods with the Case of Main Battle Tank by Ranking Efficient Units in DEA)

  • 김재오;김재희;김승권
    • 한국국방경영분석학회지
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    • 제33권2호
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    • pp.61-73
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    • 2007
  • 본 연구의 목적은 미래 기술예측에 사용되는 TFDEA(Technological Forecasting with Data Envelopment Analysis)의 문제점을 살펴보고 이의 개선방향을 찾아 주력전차의 기술예측 문제에 적용해 보는 것이다. 기존의 TFDEA는 복수의 DMU(Decison Making Unit)를 효율적 DMU로 판정하는 DEA(Data Envelopment Analysis)의 특성상 실제로는 그다지 효율적이지 않은 DMU까지 포함해서 기슬예측을 수행함으로써 예측 결과의 정확도가 저하될 수 있다. 본 연구에서는 DEA의 확장된 개념을 적용하여 평가 대상 DMU에 대한 순위를 산정한 후 이를 토대로 기술 예측을 시행하는 방법을 검토해 보았다. 이를 위해 일반적인 DEA기반의 순위선정 방법 중 대표적인 Super-efficiency, Cross-efficiency, CCCA(Constrained Canonical Correlation Analysis)을 TFDEA에 결합 적용하고 이들을 비교해 보았다. 제시된 방법을 주력 전차의 미래 기술 예측 문제에 적용한 결과 CCCA를 이용한 순위선정방법이 실제 실현된 기술 수준과 비교했을 때 통계적으로 가장 작은 오차율을 보였다.

다분류 SVM을 이용한 DEA기반 벤처기업 효율성등급 예측모형 (The Prediction of DEA based Efficiency Rating for Venture Business Using Multi-class SVM)

  • 박지영;홍태호
    • Asia pacific journal of information systems
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    • 제19권2호
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    • pp.139-155
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    • 2009
  • For the last few decades, many studies have tried to explore and unveil venture companies' success factors and unique features in order to identify the sources of such companies' competitive advantages over their rivals. Such venture companies have shown tendency to give high returns for investors generally making the best use of information technology. For this reason, many venture companies are keen on attracting avid investors' attention. Investors generally make their investment decisions by carefully examining the evaluation criteria of the alternatives. To them, credit rating information provided by international rating agencies, such as Standard and Poor's, Moody's and Fitch is crucial source as to such pivotal concerns as companies stability, growth, and risk status. But these types of information are generated only for the companies issuing corporate bonds, not venture companies. Therefore, this study proposes a method for evaluating venture businesses by presenting our recent empirical results using financial data of Korean venture companies listed on KOSDAQ in Korea exchange. In addition, this paper used multi-class SVM for the prediction of DEA-based efficiency rating for venture businesses, which was derived from our proposed method. Our approach sheds light on ways to locate efficient companies generating high level of profits. Above all, in determining effective ways to evaluate a venture firm's efficiency, it is important to understand the major contributing factors of such efficiency. Therefore, this paper is constructed on the basis of following two ideas to classify which companies are more efficient venture companies: i) making DEA based multi-class rating for sample companies and ii) developing multi-class SVM-based efficiency prediction model for classifying all companies. First, the Data Envelopment Analysis(DEA) is a non-parametric multiple input-output efficiency technique that measures the relative efficiency of decision making units(DMUs) using a linear programming based model. It is non-parametric because it requires no assumption on the shape or parameters of the underlying production function. DEA has been already widely applied for evaluating the relative efficiency of DMUs. Recently, a number of DEA based studies have evaluated the efficiency of various types of companies, such as internet companies and venture companies. It has been also applied to corporate credit ratings. In this study we utilized DEA for sorting venture companies by efficiency based ratings. The Support Vector Machine(SVM), on the other hand, is a popular technique for solving data classification problems. In this paper, we employed SVM to classify the efficiency ratings in IT venture companies according to the results of DEA. The SVM method was first developed by Vapnik (1995). As one of many machine learning techniques, SVM is based on a statistical theory. Thus far, the method has shown good performances especially in generalizing capacity in classification tasks, resulting in numerous applications in many areas of business, SVM is basically the algorithm that finds the maximum margin hyperplane, which is the maximum separation between classes. According to this method, support vectors are the closest to the maximum margin hyperplane. If it is impossible to classify, we can use the kernel function. In the case of nonlinear class boundaries, we can transform the inputs into a high-dimensional feature space, This is the original input space and is mapped into a high-dimensional dot-product space. Many studies applied SVM to the prediction of bankruptcy, the forecast a financial time series, and the problem of estimating credit rating, In this study we employed SVM for developing data mining-based efficiency prediction model. We used the Gaussian radial function as a kernel function of SVM. In multi-class SVM, we adopted one-against-one approach between binary classification method and two all-together methods, proposed by Weston and Watkins(1999) and Crammer and Singer(2000), respectively. In this research, we used corporate information of 154 companies listed on KOSDAQ market in Korea exchange. We obtained companies' financial information of 2005 from the KIS(Korea Information Service, Inc.). Using this data, we made multi-class rating with DEA efficiency and built multi-class prediction model based data mining. Among three manners of multi-classification, the hit ratio of the Weston and Watkins method is the best in the test data set. In multi classification problems as efficiency ratings of venture business, it is very useful for investors to know the class with errors, one class difference, when it is difficult to find out the accurate class in the actual market. So we presented accuracy results within 1-class errors, and the Weston and Watkins method showed 85.7% accuracy in our test samples. We conclude that the DEA based multi-class approach in venture business generates more information than the binary classification problem, notwithstanding its efficiency level. We believe this model can help investors in decision making as it provides a reliably tool to evaluate venture companies in the financial domain. For the future research, we perceive the need to enhance such areas as the variable selection process, the parameter selection of kernel function, the generalization, and the sample size of multi-class.

플립칩 본딩용 비전도성 접착제의 속경화거동 평가기법 (Evaluation Method for Snap Cure Behavior of Non-conductive Paste for Flip Chip Bonding)

  • 민경은;이준식;이소정;이성;김준기
    • Journal of Welding and Joining
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    • 제33권5호
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    • pp.41-46
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    • 2015
  • The snap cure NCP(non-conducive paste) adhesive material is essentially required for the high productivity flip chip bonding process. In this study, the accessibility of DEA(dielectric analysis) method for the evaluation of snap cure behavior was investigated with comparison to the isothermal DSC(differential scanning calorimetry) method. NCP adhesive was mainly formulated with epoxy resin and imidazole curing agent. Even though there were some noise in the dielectric loss factor curve measured by DEA, the cure start and completion points could be specified clearly through the data processing of cumulation and deviation method. Degree of cure by DEA method which was measured from the variation of the dielectric loss factor of adhesive material was corresponded to about 80% of the degree of cure by DSC method which was measured from the heat of curing reaction. Because the adhesive joint cured to the degree of 80% in the view point of chemical reaction reveals the sufficient mechanical strength, DEA method is expected to be used effectively in the estimation of the high speed curing behavior of snap cure type NCP adhesive material for flip chip bonding.

DEA에서 교차효율성의 공격적 정형화 (An Aggressive Formulation of Cross-efficiency in DEA)

  • 임성묵
    • 한국경영과학회지
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    • 제33권4호
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    • pp.83-100
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    • 2008
  • We propose a new aggressive formulation of cross-efficiency in Data Envelopment Analysis(DEA). In the traditional aggressive formulation, the efficiency score of a test DMU is maximized as the first goal while an average of efficiency scores of peer DMUs is minimized as the second goal. The proposed model replaces the second goal with the minimization of the best efficiency score of peer DMUs. We showed the model is a quasi-convex optimization problem, and for a solution method we developed a bisection method whose computational complexity is polynomial-time. We tested the model on 200 randomly generated DEA problems, and compared it with the traditional model in terms of various criteria. The experimental results confirmed the effectiveness and usefulness of the proposed model.