• 대한전기학회:학술대회논문집
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• 대한전기학회 2006년도 제37회 하계학술대회 논문집 A
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• pp.436-437
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• 2006

Porcelain insulators have generally been used in Korea but polymer insulators which are superior in that they are light weight, explosion proof, impact proof, economical with construction characteristics, have been in use for the 154kV transmission line since 1999 following a worldwide trend towards the reduced weight, simplification and compact usage of new material insulators. However there have been approximately 500 cases of forest fires in Korea, so the transmission lines that for the most part pass through mountainous areas have been highly effected and the highly polymerized compound polymer insulator has raised concern about reliability in cases of exposure to forest fires. Therefore for the reliability assessment of the effect of forest fires on polymer insulators, mechanical and electrical characteristics are analyzed by an artificial flare test device and transmission facility surrounding conditions along with forest fire characteristics are surveyed. In addition to this, actual 90kV energized transmission line was tested with an artificial forest fire and the expanded usage of polymer insulators is presented through the analysis of mechanical and electrical characteristics and physical properties, and a study on the influence of forest fires on polymer insulators.

• 한국IT서비스학회지
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• 제6권3호
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• pp.69-86
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• 2007

As most of firms related with P2P services change their free services into fee-charging services, the problems of intellectual property rights are solved to satisfactory extent. Accordingly, P2P systems become more popular with the general public. In this respect, it is thought to be very important to research on the critical factors affecting usage of P2P systems. Although it is strongly expected that the characteristics of users activities in virtual communities affect the intention to re-use P2P systems, relatively few attention have been paid to this question. Therefore, this paper is to present empirical evidence to explain how the characteristics of users activities in virtual communities affect re-use intention of P2P services. The theoretical contribution of this study is that the characteristics of users activities in virtual communities is theoretically derived from the comprehensive literature review and the logical reasoning, and that the research model of the relationship between the users activities' characteristics in virtual community and the re-use intention of P2P services is proposed and empirically validated, which is expected to expand explaining power of the TAM(Technological Acceptance Model). Also, the practical implication is to provide the guideline to support the successful strategic planning for development and.operation of P2P services through the virtual communities.

• Journal of Information Technology Applications and Management
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• 제24권4호
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• pp.215-227
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• 2017

The development of information technology are leading to the rapid evolution of SNS (Social Networking Services) in various directions and industries. Initially, SNS have been used as the form of networking between user's groups. Currently SNS has been developed towards multiple purposes and platforms such as the promotion and the advertising of a company. There are many SNSs including QQ, Weibo, and Wechat and so on in China. However, the use of companies in terms of advertising and information sharing with the customers do not meet the trend in China. Especially, there were little researches for Chinese travel agencies how to utilize SNS for attracting new customers and making them contribute to the firm's performance. In this study, we try to investigate the impact of the firm's characteristics and the usage of SNS on the performance of Chinese travel agencies. Based on Top 100 China travel agencies in 2009, we analyzed the relationships between firm's characteristics and the usage of SNS, and firm's performances in 2013. We expect that our study can contribute to the increasing academic and practical needs on the empirical evidence of the impacts of the SNS utilizations on the firm's performance.

• 한국IT서비스학회지
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• 제18권3호
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• pp.75-93
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• 2019

Digital twin technology is one of the key technologies to strengthen the competitiveness of manufacturing industry from the viewpoint of digital transformation in the era of $4^{th}$ industrial revolution. In this research, the important role in using digital twin technology in product design, This paper summarizes and empirically verifies the technical characteristics of digital twins, a key concept in the digital transition of the manufacturing industry. In this study, the technology characteristics of digital twin which is key concept in the digital transformation of manufacturing industry are summarized and empirically validated which factors militate a critical role in the use of digital twin technology in product design which is key area of product development. As a result of analysis, datafication, intellectualization which are characteristics of digital twin technology and task characteristics of product design influence Task Technology Fit (TTF) and Task Technology Fit (TTF) influences Technology (UTAUT) And finally, performance expectancy, effort expectancy, social influence and facilitating conditions affect usage intention.

• 한국대기환경학회지
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• 제15권5호
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• pp.687-696
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• 1999

Characteristics of four publicly-available accidental release models, ALOHA, SLAB, HGSYSTEM, and DEGADIS, are compared. These models are world-widely used and recently recommended by the Chemical Dispersion and Consequence Assessment(CDCA) Working Group of the United States as models applicable to generally broad safety-basis documentation applicatons. Four release scenarios are assumed by referring to the usage and storage conditions of toxic substances in the field as well as the USEPA model guideline(1993). Sensitivity of impact radius by varying meteorological conditions is tested in typical and worst-case meteorological conditions. The results show that ALOHA generally gives conservative estimates and the results from HGSYSTEM are sensitive to variations in meteorological conditions.

• 한국농촌건축학회논문집
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• 제4권2호
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• pp.63-77
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• 2002

Recently the change of social environment has influence on the conditions of space for the community welfare center. And so the relation of space and function required the change. The important role of the social welfare center is family welfare, domiciliary and community care, community organization etc. In this sence, this study explore the condition of space planning for the community welfare center. For this study, it was reviewed the role and function, the service program, the usage characteristics. In sum, the useful data were collected, analyzed, and synthesized through case study and could be used in the guidelines as reference information for the future centers.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 2010년 춘계학술대회논문집
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• pp.252-257
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• 2010

The availability of the thermal energy has been deeply recognized recently to encourage the cascade usage of thermal energy from combustion. Within the frame work, a 1 kW class Stirling engine based cogeneration system has been proposed for a unit of a distributed energy system. The capacity has been designed to be adequate for the domestic usage, which requires high compactness as well as low emission and noised. To develop a highly efficient system with satisfying these requirements, a premixed slot flame burner has been proposed and a series of numerical simulation has been performed to establish a design tool for the combustion chamber. The thermal radiation model has been found to highly affect the computational results and a proper resolution to analyze the heat transfer characteristics of the high temperature heat exchanger. Finally, the combustion characteristics of the premixed flame with the metal fiber type burner has been studied.

• Asia pacific journal of information systems
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• 제15권1호
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• pp.1-24
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• 2005

The purpose of this study is to identify the factors affecting the performance of knowledge management systems. To extend DeLone & MeLean's model, we included the user specialization in the information systems success model. The questionnaires are collected from 109 knowledge management system users. The major findings are summarized as followed. First, system characteristics such as ease of use, response time, and knowledge management process support affect the knowledge management systems usage. Second, knowledge characteristics such as relevancy, completeness, reliability, importance, and currency also affect the knowledge management systems usage. Third, the end-users are satisfied with the knowledge management systems because it is easy to use and relevant.

• 한국조리학회지
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• 제12권4호
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• pp.284-298
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• 2006

This study aimed at defining radish cultivars to a best cooking usage based on their physiochemical and textural characteristics of Nabakkimchi. Baekkwang, Daeburyong, Chungwoon and Taebaek were used as four types of radish cultivars. Nabakkimchi was stored at $8^{\circ}C$ either after fermentation for 12 hours at $25^{\circ}C$(A group) or without preliminary fermentation(B group). As storage period went by, lightness was decreased. Haziness of liquid showed sudden increase at preliminary fermentation in group A, while it increased between the third day and fifth day in group B. Hardness of 'Fall season' type was relatively high after storage. pH was suddenly decreased on the second day in A group and on the fifth day in B group. Acidity was suddenly increased on the second day in A group and since the third day at B group. As a result of sensory evaluation, Chungwoon stored for 2 days after preliminary fermentation was the best variety.

• Journal of Korean Dental Science
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• 제15권2호
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• pp.112-120
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• 2022

In this article, the contemporary root canal treatment procedure using nickel-titanium (NiTi) instruments was reviewed to understand the correlations between the properties of files and safety of the clinical usage. Literatures were reviewed according to the process of clinical procedure of the root canal preparation, mainly for shaping during orifice flaring, glide-path preparation, and main canal instrumentation. Considering the reasons for NiTi file fracture, clinically implacable issues and ideas were discussed to reduce the fracture risk and increase clinical efficiency of the NiTi file systems. Various kinds of NiTi file systems have their own characteristics and properties given from their geometries and heat treatments and so on. Proper selection and careful usage of the NiTi file systems may reduce the risk of file fracture and increase the efficiency of NiTi file systems. Understanding of the clinical implications from the mechanical properties and characteristics of the engine driven NiTi instruments may decrease the risk of NiTi file fractures and increase the success rate in root canal treatment.