• Journal of the Korea Institute of Information and Communication Engineering
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• v.20 no.9
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• pp.1717-1722
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• 2016

Availability, one of the important metrics used to assess the performance of network system, is defined as the probability that a system is operational at a given point in time under a given set of environmental conditions. To improve the availability of the network service, the redundancy models and the rejuvenation schemes are the effective schemes to be typically used. In this paper, we analyse the effect of 2N redundancy model and/or rejuvenation scheme on the availability of network service. The 2N redundancy model consists of one active and one standby component and the performance of time-based rejuvenation scheme mainly depends on its rejuvenation period. We design stochastic reward net model for the 2N redundancy model with time-based rejuvenation scheme and analyse the service availability of the model using stochastic Petri net package. We provide some numerical examples of the service availability, which shows that the system with rejuvenation has higher availability than the system without rejuvenation.

• Proceedings of the SAREK Conference
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• 2008.06a
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• pp.48-53
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• 2008

The performances of the building service equipment relay on the individual superintendent's share for the assessment of performance, fault detection, deterioration diagnosis of the building service equipment. A major use of building energy management system(BEMS) is for monitoring plant and building's energy consumption. National building management system (N-BMS) presented in this study links buildings into a network group in order to monitor and control the buildings. How to construct the N-BMS was considered to save energy resource and to conserve performance of building service equipment. The FEMIS, facility, energy/environmental management & information system, for building service offer management process integrated with BAS, FMS and EMS and so on.

• Fashion & Textile Research Journal
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• v.11 no.1
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• pp.66-74
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• 2009

The purpose of this study is to identify the factors mainly recognized by customers regarding environmental elements of clothing store. The respondents are classified into several groups according to their preferences on the environmental elements of clothing store. Also the relationship between the factors and the shopping characteristics of customers is reviewed based on the results. This survey was carried out through a questionnaire of male and female university students(Busan region) in their twenties. The data were analyzed by using Factor analysis, Cluster analysis, one-way ANOVA, Duncan test as a post identification and regression analysis. The results of this research can be summarized as follows; The perceived 7 factors about environmental elements of clothing store were service policy, store atmosphere, product variety, shopping convenience, trend of products, freedom of shopping and reception service. The respondents were classified into three groups(high recognizing group, middle recognizing group and low recognizing group) by the level of recognizing 7 factors. There were significant differences among 3 groups divided by the degree of recognizing the factors regarding environmental elements of clothing store and there was the meaningful relationship between these 7 factors and shopping characteristics. The high recognizing group has shopping characteristics like more shopping time, large expenditure for clothing and a lot of comparative stores. They are frequently in contact with clothing shopping environment and easily purchase clothes. Finally, the factors perceived by the environmental elements of clothing store significantly affected the shopping characteristics of the customers. So, store managers have to look for the perceived environmental elements of store by business and seek after the marketing factors which efficiently stimulate consumer.

• Journal of Environmental Science International
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• v.22 no.4
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• pp.481-492
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• 2013

In this study, the use survey of domestic and international weather information on coastal regions and the demand survey (e.g. general and in-depth surveys) for customer needs with coastal industries were carried out to design customized coastal weather contents. The general demand survey showed that most of the customers working in the coastal industries were interested in a short-term forecast, such as a general weather outlook (approximately 29% of the total respondents) and typhoon information (19%), and they preferred to be given the forecast information from new media such as the internet web-pages (36%) and mobile utilities (23%) rather than old media such as TV (16%) and radio (11%). In addition, only 31% of the total respondents were found to be satisfied with the use of the current coastal weather service. This low percentage might mainly be a result of lack of information accuracy (about 64%) and diversity (28%). From in-depth survey with site visiting, the need of coastal weather contents, such as weather elements, data form, a tool of communication, and forecast interval, differed with the working stages in three coastal industries (e.g. shipbuilding, maritime trade, and passenger transport industries).

• Journal of Forest and Environmental Science
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• v.24 no.3
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• pp.165-169
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• 2008

This study attempts to analyze the relationship between forest volume and age based on 5th NFI data and spectral characteristics of satellite imagery using ASTER sensor in Korea. Forest stand volume and age had the negative correlation with the spectral reflectance in all of the band (Blue, Green, Red, SWIR). With increasing of stand volume and age, spectral reflectance decrease. The spectral reflectance of band1 showed the highest correlation between stand volume and spectral reflectance among the VNIR wavelength. The spectral reflectance band 1, 2 (visible wavelength) and stand age have high correlation compared to other bands. The correlation coefficients between forest volume and vegetation indices have low relationship. This result indicates that the reflectance of blue band may be important factor to improve the potential of optical remote sensing data to estimate forest volume and age.

• Journal of Computing Science and Engineering
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• v.2 no.4
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• pp.412-427
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• 2008

We propose ID-exchange protocol for Connectionless Location-Awareness Service (CLAS) to locate mobile nodes in indoor sensor network. When adapting location-awareness service to sensor network, the target system must be designed in accordance with various metrics which reflect the system requirement. We especially consider sustainability of the existing service which has been provided for its original purpose, such as environmental monitoring. The detailed meaning of sustainability here is that, even if location-awareness service is newly added to the existing service, the system must be assured to retain a stable network condition, and to deal with newly caused traffic properly. The CLAS ID-exchange protocol is especially designed for fixture and mobile nodes communication to achieve these properties. The protocol operates on 802.15.4 MAC layer to make mobile node work independently of the procedure to build routing table of fixture node, so a stable routing condition can be achieved even if there are many mobile nodes. Moreover, the dedicated frequency channel is assigned only for this protocol, so that traffic caused by location-awareness service can be distributed to another channel. A real system adapting the protocol was implemented to monitor fire and authorities' positions. We verified the overhead and elapsed time for location-awareness. The result shows the proposed protocol has a high performance in detecting speed, traffic distribution, and stability of overall network.

• Journal of Preventive Medicine and Public Health
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• v.24 no.1 s.33
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• pp.16-28
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• 1991

Service diversification is recognized as an important strategy against turbulent environmental change. This study is designed to find out the trend of service diversification in Korean health care organizations and also to identify factors associated with the degree of service diversification. Data were collected from 69 hospitals out of 71 hospitals with over 300 beds. Important findings are summarized below. 1. Types of diversification are closely related to hospital size. Large hospitals have a tendency to provide sophisticated services requiring specialized skills and equipment, while small hospital have concentrated their efforts on health screening programs. 2. The more competitive and bigger hospitals are, the greater number of services that provide. Also, hospitals operating rational management information systems provide more services. Contrary to the expectation hospitals with a low performance during last 3 years showed more service diversification. 3. A trend of more diversification was observed in hospitals whose chief executive officer used a prospector strategy. 4. A multiple regression analysis revealed that bed size, competitive environment, degree of rational management, and the growth pattern were significantly associated with the service diversification.

• Journal of Information Technology Services
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• v.12 no.2
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• pp.301-319
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• 2013

Wireless and mobile communication technologies enable individuals who trade stocks and bonds to use mobile-based trading services. Due to rapidly developing mobile technologies and adoption of the advanced/smart mobile devices such as smart phones and tablets, the use of mobile trading systems (MTS) have increased at an unexpected rate. Although many prior studies measured service quality on various service-related fields, there are few studies that is related to mobile trading systems compared to more traditional PC-based home trading systems. This research searches determinants of service quality for mobile trading systems and examines the effects of these factors on the intention to mobile trading systems' continuous use. Through an extensive literature review, this research finds three dimensions for mobile trading systems : interaction quality, service environment quality, and service outcome quality. The result of analysis shows that personalization, connectivity, ease of use, informativeness, and monetary value enhance the intention to continuous use. Considering environmental conditions such as the high rate of MTS adoption among individual users and stiffer competition among securities firms, these findings may help practically securities firms' shaping MTS system development strategies for individual users' continuous use and for increasing new users adoption.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.5
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• pp.2465-2473
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• 2013

This study reviews planning support systems (PSS) in the context of the development processes of urban models(focusing on Land-Use Transport Models, LUTM) and Geographic Information Systems (GIS), both of which are key components of PSS supporting spatial plannings like urban and regional planning. It also explores changing planning environments like increased demands of citizen participation, especially in the environmental sector like global warming, and intensified development of Information technologies based on Internet and mobile networks. As a conclusion this study proposes a prototype of portal service to support low-carbon city planning to mitigate the greenhouse gas as an alternative to supplement or reinforce PSS, reflecting the changing planning environments.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.10a
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• pp.172-175
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• 2003

This paper deals with the network interface of research and observation instruments in the oceanographic research vessel with an establishment of related database for measured information. The system is implemented to integrated communication network system which allows to effective survey by using real time observation and GUI(Graphic User Interface). The system also consists of the LAN systems and serial interface to link chemical, physical, biological and environmental relations. And, other network service and vessel data service for data communication between vessel and earth station such as INMARSAT-B, WWW service, BBS, E-Mail etc. are needed for integrated communication network system.