• 한국의학물리학회지:의학물리
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• 제13권1호
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• pp.27-31
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• 2002

6MeV 전자선의 output 인자를 결정하기 위해 간편하게 output 인자를 예측하는 수단인 1D(Dimension) 방법을 이용하였으며 그리고 1D 방법으로 결정된 output 인자를 개별적 beam cutout 하에서 직접 측정한 output 인자와 비교하여 1D 방법의 정확성을 분석하였다. 1D 방법은 정방형 field의 한 변과 항상 동일한 한 변을 갖는 사각형 field의 output 인자로서 규정되며, 임의의 사각형 field (X,Y)의 output은 1D output 인자의 곱으로 주어진다. 6MeV 전자선의 대단히 큰 정방형 field의 output은 1D 방법을 사용하면 실제보다 높은 값을 나타내지만 교정인자 CF=C.[(X-10)(Y-10)/$\mid$(X-10)(Y-10)$\mid^{1/2}]$를 적용하면 개별적 cutout하에 직접 측정된 output 인자와 잘 일치하였으며 그 오차 범위는 1% 이내였다.

• 한국환경과학회지
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• 제21권4호
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• pp.461-470
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• 2012

Agriculture is more influenced by environmental factors rather than other industries. Among the environmental factors, the meteorological conditions mainly impact the output of agricultural products. Hence, the purpose of this study is to analyze the impact of meteorological factors on the output of elemental agricultural products. As a first step, we obtained the data of the meteorological factors (i.e., precipitation, humidity, temperature, insolation, snowdrifts, wind velocity) and the output of the various agricultural products (i.e., grain, fruits and vegetables, root crops, green vegetables, seasoned vegetables, fruits, special crops) from the year 1990 to 2009 (20 years) of Seoul and the six metropolitan cities in Korea. Then, the analysis of the correlation between the agricultural product with the largest output and the meteorological factors of the place where the corresponding agricultural product is most produced, was carried out in order to determine the core meteorological factor that most impacts the output of agricultural product. The correlation analysis revealed that humidity, insolation and wind velocity have been the crucial meteorological factors to influence the output of the agricultural products. From the result, we can induce that the meteorological forecast information about the vital meteorological factors, i.e., humidity, insolation and wind velocity, facilitates the optimized cultivation plan to maximize the output of agricultural products.

• 산업공학
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• 제22권1호
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• pp.44-55
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• 2009

We propose a method for selection of input-output factors in DEA. It is designed to select better combinations of input-output factors that are well suited for evaluating substantial performance of DMUs. Several selected DEA models with different input-output factors combinations are evaluated, and the relationship between the computed efficiency scores and a single performance criterion of DMUs is investigated using decision tree. Based on the results of decision tree analysis, a relatively better DEA model can be chosen, which is expected to well represent the true performance of DMUs. We illustrate the effectiveness of the proposed method by applying it to the efficiency evaluation of 101 listed companies in steel and metal industry.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제54권4호
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• pp.188-194
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• 2005

There are many factors that affect on the system output of Photovoltaic(PV) power generation; the variation of solar radiation, temperature, energy conversion efficiency of solar cell etc. This paper suggests a methodology for calculation of PV generation output using the probability distribution function of irradiance, PV array efficiency and revision factors of solar cell conversion efficiency. Long-term irradiance data recorded every hour of the day for 11 years were used. For goodness-fit test, several distribution (unctions are tested by Kolmogorov-Smirnov(K-S) method. The calculated generation output with or without revision factors of conversion efficiency is compared with that of CMS (Centered Monitoring System), which can monitor PV generation output of each PV generation site.

• 토지주택연구
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• 제9권4호
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• pp.33-42
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• 2018

As a radiant heating panel gets more popularity, the need to study on evaluation method of thermal output of the panel also becomes increasing. Generally, the chamber using method is applied to evaluate the thermal output through an experiment. However, the chamber using method cannot be used due to the limitations on space and cost. EN1264 addresses the test equipment to evaluate the thermal output by using simpler experimental setup, and introduces application method in detail. However, there is not enough description of control methods to meet the experiment condition, and it is difficult to meet this when practical experiment. Therefore, this paper analysed the control error factors of when the thermal output experiment is performed. When EN1264 method is applied to evaluate the thermal output of the radiant floor heating panel, the error factor which is caused by the characteristic of test equipment cannot be removed by the control methods of chamber using method. In addition, the error factor can be occurred at the element which is located out of the control system. These possible error factors are defined as the characteristic error factors.

• 기술혁신연구
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• 제21권1호
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• pp.165-198
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• 2013

본 연구의 목적은 R&D성과를 높이기 위해 신제품개발프로세스 단계별로 연구 개발을 수행하면서 고려되어져야 할 위험요인을 식별하고, 위험요인의 영향을 분석하기 위한 것이다. 이를 위하여 본 논문은 대한민국의 대표 IT 기업인 삼성 및 LG전자의 계열사가 최근 5년 이내 개발한 IT 신제품에 대한 설문조사를 기반으로 하였다. 연구는 우선적으로 신제품개발프로세스에 따라서 위험요인을 식별하였고, 설문지를 통해 식별된 위험요인을 평가하였다. 위험의 영향을 분석하기 위해 R&D 성과를 기반으로 로지스틱 회귀분석을 실시하였다. 위험요인의 영향은 저 성과 그룹에서 높게 나타남을 알 수 있었다. 고 성과 그룹은 R&D 성과를 높이기 위해 프로젝트를 관리하는데 있어서 위험을 중요한 일로 간주하고 있었으며, 효과적으로 위험요인을 잘 관리하였다. 결론적으로 R&D 성과를 높이기 위해 신제품개발프로세스 단계별로 위험요인을 식별하고 분석한 후, 영향력이 큰 위험을 집중적으로 관리하는 위험관리활동이 필요함을 알 수 있었다.

• 전기의세계
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• 제14권4호
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• pp.8-17
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• 1965

Firstly, this study has analyzed the following factors affecting the optimum specifications and design of distributive transformers: 1. Facilities installation cost per unit power output. 2. Facilities operating & maintenance cost per unit power output. 3. Production cost per unit power output. 4. Load factor. 5. Loss factor. Secondly, it has clarified the relations between the following factors and the specifications and design of distributive transformers; 1. No-load loss., 2. Load loss., 3. Voltage regulation., 4. Exciting current. Finally, it has determined the method of the most economic design for the transformers using the above factors and relations, and, for optimum the illustrative purpose, suggested their optimum specifications, way of evaluation, and merits by means of typical example.

• 한국경영과학회지
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• 제23권3호
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• pp.75-90
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• 1998

The improper use of input and output factors in DEA has a critical and negative impact on the efficiency measurement and the discernment of decision making units(DMUs) : hence the proper selection Process of the factors should precede the actual applications of DEA. In this paper, we propose a new approach to selecting proper factors based on Tofallis' partial efficiency evaluation method(1996). With the approach, the factors aye clustered by measuring their respective partial efficiencies and analyzing the rank correlations of them. The method and procedure we propose in this paper are then applied to measure the efficiencies of the public libraries in Seoul District area, and the results show that the proposed approach can provide meaningful information to improve discernment of the DMUs while using less number of input factors (and less information). The proposed method can be effectively used in the situation where the number of the DMUs to be considered is relatively small compared to the number of available input and output factors, which usually lessens the power to identify the inefficient units in DEA.

• 기술혁신학회지
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• 제7권2호
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• pp.283-304
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• 2004

Evaluating the sources of economic output is obviously important, and numerous attempts have been made to judge the impact of many different factors on economic output. It is widely accepted that high-technology(HT) is one of the important factors in economic output. This paper empirically explores the impacts of HT exports on economic output using a cross-county analysis based on data from 89 countries for the year 1988-2000. To this end, several versions of the neoclassical growth models, explicitly including HT exports, are estimated. Subject to the appropriate caveats, the results provide further support for several key conclusions of the former studies - investment in physical capital, population growth, and the human capital are important in accounting fer economic output across countries. More importantly, it is concluded that HT exports significantly contribute to economic output. Interestingly, the conclusion is valid f3r developing countries, but not far developed countries.

• Asia pacific journal of information systems
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• 제23권4호
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• pp.151-175
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• 2013

This study investigates the potential components for academic research collaboration, and the factors that make it possible to achieve higher academic productivity. The components include collaboration factors and a collaboration model. We use two major collaboration factors to develop a framework for understanding the mechanisms that influence academic research collaborations: motivational factors and mediating factors. Motivational factors include self-motivation and trust whereas mediating factors are collaboration orientation and peer support. We analyze the effect for use of e-collaboration with research performance, reward, and satisfaction with e-research output. A survey of academicians was conducted, and by using the factor analysis and the structural equation model with SPSS 20 AMOS, we illustrate the possible influence of these factors on research performance and satisfaction. We discovered that both motivational and mediating factors play important roles on the success of academic research. This study offers several implications for academicians. We develop a parsimonious research model, which is related to e-collaboration in academic research. This unique model offers academicians to achieve good publication output from the research team. The motivational factor, self-motivation and trust, are important factors which has received positive impact of mediating factor collaboration orientation and peer support. Our research sheds light on the crucial factors for use of e-collaboration which offer the ultimate effect on performance and satisfaction with e-research output. Satisfaction motivates people to work more and more on the field of their interest, thereby influencing the performance of academicians. Rewards should be distributed according to performance of the individual, which will motivate the person to become more enthusiastic for his work of interest. Our evidence suggests that in understating the collaborative process, one must account for the context in which the collaboration occurs, the motivation of the collaborators, the scope and nature of the project, the roles and activities undertaken, and interpersonal processes such as trust. Researchers' motivations for engaging in collaboration were both instrumental and intrinsic.