• International Journal of Automotive Technology
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• 제4권4호
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• pp.157-164
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• 2003

An experimental and numerical study was performed to investigate the macroscopic and microscopic atomization characteristics of high-speed diesel spray issued from the common-rail injection system. For the experiments, spray visualization system and a phase Doppler particle analyzer system were utilized to obtain the spray atomization characteristics such as the process of spray development, spray tip penetration, and SMD distribution. In order to analyze the process of spray atomization with KIVA-3 code, the TAB breakup model is changed to the KH-DDB competition model, which assumes the competition between the wave instability and droplet deformation causes the droplet breakup above the breakup length. The calculated results were also compared with the experiments in terms of spray tip penetration and SMD distribution. The results provide the process of spray development, axial and radial distribution of SMD, and calculated overall SMD as a function of time after start of injection.

• 경영과학
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• 제19권2호
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• pp.205-220
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• 2002

As the business structure of many industries changes under IT progress and internet economy, the customer information has emerged a key factor in setting up the management policy. The customer has come to replace the product as a central figure in business competition. The domestic life insurance market has also experienced the rapid structural changes in IT time. The competition in the insurance industry to maintain the existing membership and to attract the new members gets stronger under such a new business circumstance. Accordingly, it is necessary for an individual insurance company to develop a systematic marketing plan, based on the customer information, to be competitive in the market. Unlike other studies in which customer characteristics are neglected, this study attempts to utilize the customer information by applying the data mining technique, and then suggests an efficient marketing strategy that could prevail in the competitive business environment.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2000년도 하계학술대회 논문집 A
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• pp.376-378
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• 2000

The current worldwide electricity market introduced competition, which is breaking up the monopoly structure and also enforcing phased structural reform in South Korea. The change of the electricity charge from cost base to price base due to the introduction of the electricity market competition causes consumer to choose a variety of charge schemes and a portion of loads to be affected by this change. Therefore, in order to find a mathematical model of the sensitively-responding-to-price loads and reflect this to the DSM demand management, the price-sensitive load model is needed. Thus, this paper first proposes the composite price-sensitive load model that is expressed as a function of price, presents the methodology to estimate price-sensitive load model at each bus by bus load compositions.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 D
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• pp.2097-2098
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• 2006

In this study, we introduce the hybrid optimization of fuzzy inference systems that is based on Hierarchical Fair Competition-based Parallel Genetic Algorithms (HFCGA). HFCGA is a kind of multi-populations of Parallel Genetic Algorithms(PGA), and it is used for structure optimization and parameter identification of fuzzy set model. It concerns the fuzzy model-related parameters as the number of input variables, a collection of specific subset of input variables, the number of membership functions, and the apexes of the membership function. In the hybrid optimization process, two general optimization mechanisms are explored. The structural optimization is realized via HFCGA method whereas in case of the parametric optimization we proceed with a standard least square method as well as HFCGA method as well. A comparative analysis demonstrates that the proposed algorithm is superior to the conventional methods.

• 한국디지털정책학회:학술대회논문집
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• 한국디지털정책학회 2004년도 춘계학술대회
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• pp.53-67
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• 2004

On the base of IT growth, competition between countries for preoccupation of digital content market is keen. And it is prospected that the development of digital content industry will be more rapid with the base of telecommunication infra-structure(for example internet, digital broadcasting) which is the main channel for distribution of digital content. The bill of "Act for Development of Online Digital Content Industry", has passed the national assembly jan, 2002, and "Draft Blueprint for Developing Online Digital Content Industry(2003$\sim$2005)" was made on the base on that law feb, 2003. And we can find measures for protect the digital content manufacture in the laws such as "Literary Property Law", "Trademarks Law" and "law for prevention of unfair competition". On this study we suggested three measures to make digital content industry more profitable by the method of research of related law and industry survey.

• 대한전기학회논문지:전력기술부문A
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• 제51권6호
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• pp.269-275
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• 2002

Recently, Korea's electric industry has experienced substantial changes in its structure and function including the introduction of competition in the generation sector. Korea is in the early stages of market competition where the market price is determined by generation costs. In the future, the market Price will be determined by generators'bids. Therefore, the generators'profit is determined by market pool price, the prospects of pool price are very important for new capacity investment decision made by generators and IPPS. This study analyzes hourly marginal costs and LOLP considering basic generation mix and characteristics develops the relationship of pool price and Profit by generation-type using the change in reserve margin, and proposes basic direction for profits variation and supply-demand analysis in the electricity market in future.

• Bulletin of the Korean Chemical Society
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• 제30권10호
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• pp.2341-2344
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• 2009

Metallacyclodimers, [Ag(OTf)($L1)]_2$ and [Ag($L2)]_2(OTf)_2$ (L1 = 1,3-dibromo-2,2-bis[(isonicotinoyloxy)methyl] propane; L2 = 2,5-dimethyl-2,5-bis(isonicotinoyloxy)hexane) were constructed and characterized. The crystal structure of [Ag(OTf)($L1)]_2$ reveals a 32-membered cyclodimer, whereas that of [Ag($L2)]_2(OTf)_2$ shows a linked 34-membered cyclodimer chain via intercyclic argentophilic (Ag…Ag) interactions. [Ag(OTf)($(L1)]_2$ affords “intramolecular $\pi-\pi$ interaction cyclodimer” whereas [Ag($L2)]_2(OTf)_2$ produces a racemic mixture of “twisted cyclodimer”. Ring-conformation of the cyclodimers was affected via the competition of electrostatic interaction and argentophilic interaction.

• 한국시스템다이내믹스연구
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• 제11권4호
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• pp.5-23
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• 2010

The competition between hospitals has become an issue for many hospitals because of the sudden increased number of health providers. As the marketing or customer management have become important factors as means of competition, a number of hospital have been considered or already adopted the coordination system. A system dynamics model is developed to see the effect of the hospital coordination system. This paper after briefly explaining the structure of the system dynamics model, discusses the roles of the hospital coordination system with examples. The system dynamics model quantifies through simulations the process of effects of coordination system on the number of customers, productivities of employees (nurses and doctors), and finally the financial status. As a conclusions of the simulations and their analysis, it is concluded that coordination system could be more effective than the investment to the facilities. Since the study is based on only one hospital case, it is limited. However, it explains the mechanism of the coordination system quantitatively as well as qualitatively.

• 유통과학연구
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• 제12권7호
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• pp.37-44
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• 2014

Purpose - This study reviews changes in the automobile export-import structure between Japan and USA through a trade related index, and focuses on analyzing comparative advantage based on time-series analysis of statistical data (2000, 2005, and 2012) by using the trade intensity index (TII), revealed comparative advantage index (RCA), and trade specialization index (TSI). Research design, data, and methodology - Japan and USA have mutually complementary economic phase characteristics. Therefore, this study aimed to understand each country's trade structure, to strengthen Japan-USA economic cooperation and aimed to examine trade drawbacks to analyze causes affecting trade and ways to improve it to facilitate its expansion. Results - These two economies have immense complementary potential and, further, significantly greater profits are assured from trade between them, as compared to any other integrated regional economic community. Conclusion - Economic cooperation between these two powers can provide opportunities for industry technology cooperation through partnerships against the backdrop of accelerating competition among industries, by identifying opportunities to secure stable resource suppliers and enlarge the export market.

• ALGAE
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• 제18권3호
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• pp.225-232
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• 2003

Species composition, community structure and biodiversity of marine benthic community were studied in the rocky shore of Dongbaekseom, Busan. A total of 82 species of marine algae including 4 Cyanophyta, 11 Chlorophyta, 20 Phaeophyta and 47 Rhodophyta are listed. The dominant algal species were Ulva pertusa, Chondria crassicaulis, Corallina spp. and Melobesioidean algae. Sargassum thunbergii, Chondracanthus intermedia, Gelidium divaricatum and Ralfsia verrucosa were subdominant in cases of different seasons and vertical layers. Chthamalus challengeri, Littorina brevicula and Mytilus edulis were dominant zoobenthic species upper-middle layer of the intertidal zone. The community structure of this area seemed to be controlled by spatial competition with benthic marine algae. The species diversity indices estimated from different sources were quite different. Indices from coverage were 1.87, 3.98 from frequency, 2.26 from the average of total frequency and coverage and 2.15 from importance value. The similarity indices on the present study showed decreasing trends comparing to the previous benthic algal composition researches.