• Nuclear Engineering and Technology
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• 제53권12호
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• pp.3910-3917
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• 2021

Reactor fuel's power distribution plays a vital role in designing the new generation thermionic Space Reactor Power Systems (SRPS). In this paper, the 1/12th SPACE-R's full reactor core was numerically analyzed with two kinds of different axial power distribution, to identify their impacts on thermal-hydraulic and thermoelectric characteristics. In the benchmark study, the maximum error between numerical results and existing data or design values ranged from 0.2 to 2.2%. Four main conclusions were obtained in the numerical analysis: a) The axial power distribution has less impact on coolant temperature. b) Axial power distribution influenced the emitter temperature distribution a lot, when the core power was cosine distributed, the maximum temperature of the emitter was 194 K higher than that of the uniform power distribution. c) Comparing to the cosine axial power distribution, the uniform axial power distribution would make the maximum temperature in each component of the reactor core much lower, reducing the requirements for core fuel material. d) Voltage and current distribution were similar to the axial electrode temperature distribution, and the axial power distribution has little effect on the output power.

• Agribusiness and Information Management
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• 제6권2호
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• pp.13-23
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• 2014

The world is in the process of a structural change related to ICT convergence knowledge industries. ICT is leading to the creation of new products and services, and is making our lives more convenient, safer, and more efficient. In advanced countries, many studies have been conducted with the goal of developing new business models converged with ICT, and this is also the case in the food industry. Korea possesses world-leading ICT, and if this ICT is applied to the food industry, a world-class new business model can be developed. The u-Food System, which is in the process of development in Korea, is a next-generation food system that can allow food providers, consumers, and distributors to access various types of information about food products, including traceability, distribution, safety, quality, and freshness, and manage this information. It is a future food system that converges ICT, biotechnology and sensing technology with food. Based on the u-Food System, this paper will introduce the status of current smart quality distribution technologies that converge ICT (such as sensor tag, sensor network, LBS, GIS, and CDMA) with food technologies (such as traceability, quality, distribution management) to manage the safety and quality of fresh food in the distribution process.

• 기술혁신학회지
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• 제21권2호
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• pp.860-874
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• 2018

본 연구는 신 국제무역이론(Melitz, 2012, 2014, 2015)에 대한 실증분석을 목적으로 한다. 신 국제무역이론은 기업기술역량에 대한 이질적 기업분포가 무역효과에 미치는 영향을 중심으로 전개되고 있으며, 기업기술역량분포형태가 무역효과를 결정한다는 중요한 가정에서 출발한다. 본 연구는 실증적으로 우리나라 제조업에 기업기술역량분포를 추정하였다. 이 연구목적을 위하여 우리나라 총 기업기술역량분포를 기술혁신과 기술모방분포로 분리하였으며, 분포형태의 적합성에 대하여 통계적으로 검증하고, 신 국제무역이론기반에 대한 적정성을 평가하였다. 연구시사점으로 본 분석결과를 바탕으로 기술정책 및 산업정책 방향을 간단하게 제언하였다.

• ETRI Journal
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• 제45권2호
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• pp.267-276
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• 2023

R&D strategies of companies with low and high technological levels are discussed based on the concept of technology convergence and divergence. However, empirically detecting enterprise technology convergence in the distribution of enterprise technology (total productivity increase) over time and identifying key change factors are challenging. This study used a novel statistical indicator that captures the internal technology distribution change with a single number to clearly measure the technology distribution peak as a change in critical bandwidth for enterprise technology convergence and presented it as evidence of each technology convergence or divergence. Furthermore, this study applied the quantitative technology convergence identification method. Technology convergence appeared from the separation of total corporate productivity distribution of 69 IT companies in Korea in 2019-2020 rather than in 2015-2016. Results indicated that when the total technological level was separated from the technology leading and technology catch-up, IT companies were found to be pursuing R&D strategies for technology catch-up.

• 유통과학연구
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• 제17권1호
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• pp.89-94
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• 2019

Purpose - In recent digital information society, the most important factor of to increase the firm value of the distribution company is not the activity to increase the sales through the general advertisement of the unspecified majority by purchasing the finished product, but to grasp the needs of the consumers and to develop a new distribution platform that connects producers and consumers directly through consumer-tailored advertisements centering on e-commerce. Therefore each company in the distribution industry is spending a lot on research and development investment to innovate the distribution technology and distribution system, and the research and development investment expenditures can affect firm value. The purpose of this study is to analyze the impact of research and development investment expenditures in the distribution industry on market value of the firm. Research design, data, and methodology - As a research method, the sample firms are those which are listed on korea stock exchange market from 2011 to 2017 and the research model is Ohlson(1995) model, which is a representative valuation model using accounting information. This study analyzes the effect of distribution company's research and development investment expenditures and advertising expenditures on market value of the firm Results - The results of empirical analysis show that research and development investment expenditures for developing new distribution technology and advertising expenditures for promoting sales in the distribution company are all positively related to the market value of firm. Therefore, in describing market value of the distribution company, it is shown that the research and development investment expenditures and advertising expenditures together with the net asset and net profit are the important accounting information that explains the market value of firm. This result show that investment expenditures on research and development for the innovation of distribution technology of distribution company creates intangible intellectual assets and increases market value of the firm. Conclusions - The result of this study shows that research and development investment expenditures for the new distribution technology as well as the spending for the advertisement in the future is a very important investment expenditures that can increase the market value of the distribution company.

• KIEE International Transactions on Power Engineering
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• 제5A권2호
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• pp.159-170
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• 2005

This paper presents the design and development of a scaled down physical model for power Distribution Automation (DA) system simulation. The developed DA system simulator is useful in providing hands-on experience to utility engineers / managers to familiarize with the DA system and gain confidence in managing the power distribution system from the computer aided distribution control center. The distribution automation system simulator can be effectively used to carry out further research work in this area. This also helps the undergraduate and graduate students to understands the power distribution automation technology in the laboratory environment. The developed DA simulator has become an integral part of a distribution automation lab in the Electrical Engineering Department at Indian Institute of Technology Kanpur in India.

• 한국생산제조학회지
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• 제26권1호
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• pp.66-73
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• 2017

This study attempted to design lights with Type II distribution suitable for LED street lights based on the regulations of street light distribution developed by the Illuminating Engineering Society of North America (IESNA). The shape of an asymmetric lens, different from that of a rotationally symmetric lens, cannot be generated using a simple mathematical formula. In the first trial, the outline of the lens was fixed and simulated to confirm the distribution type. Following ISENA regulations, some problems that occurred during simulations and repeating was be modified that process is how we detected errors. Through optical research and simulations, a lens conforming to the regulations of Type II very short, Type II short, and Type II medium distributions was developed. A prototype was developed using simulation data and it was subjected to distribution tests. The results show that it can compare with property of Type II distribution.

• International Journal of Advanced Culture Technology
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• 제3권2호
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• pp.144-148
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• 2015

The paper presents the estimation of power losses in distribution transformer of Provincial Electricity Authority (PEA) distribution system at Muang district of Suphanburi province in Thailand. Data of 416 power distribution transformers composed of transformer (kVA), load current, no load loss and full load loss which were used for calculating energy losses. It was found that the total energy loss of all transformers is approximately 1,756,380 kWh/year.

• Journal of Information Processing Systems
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• 제15권1호
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• pp.100-115
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• 2019

Malicious code distribution on the Internet is one of the most critical Internet-based threats and distribution technology has evolved to bypass detection systems. As a new defense against the detection bypass technology of malicious attackers, this study proposes the automated tracing of malicious websites in a malware distribution network (MDN). The proposed technology extracts automated links and classifies websites into malicious and normal websites based on link structure. Even if attackers use a new distribution technology, website classification is possible as long as the connections are established through automated links. The use of a real web-browser and proxy server enables an adequate response to attackers' perception of analysis environments and evasion technology and prevents analysis environments from being infected by malicious code. The validity and accuracy of the proposed method for classification are verified using 20,000 links, 10,000 each from normal and malicious websites.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.462-465
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• 2002

KEPCO enforces the development about distribution automation technology continuously for 10 years and reached in fair level present. And distribution automation system was constructed actively meantime, its establishment will be completed 100% at late 2002s. Distribution automation system had been developed also in Japan, U.S.A and Europe etc. In japan, distribution automation system was established all business office to whole county. Lately, there is examining distribution automation expansion actively in developing country including China. Therefore, we try to analyze domestic and foreign technological variance as that examine foreign distribution automation trend and the development direction of domestic distribution automation technology forward.