• The Transactions of the Korean Institute of Electrical Engineers A
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• v.54 no.8
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• pp.375-387
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• 2005

This paper presents an application of parallel Genetic Algorithm-Tabu Search (GA-TS) algorithm to search an optimal solution of a service restoration in distribution systems. The main objective of service restoration of distribution systems is, when a fault or overload occurs, to restore as much load as possible by transferring the do-energized load in the out of service area via network reconfiguration to the appropriate adjacent feeders at minimum operational cost without violating operating constraints, which is a combinatorial optimization problem. This problem has many constraints with many local minima to solve the optimal switch position. This paper develops parallel GA-TS algorithm for service restoration of distribution systems. In parallel GA-TS, GA operators are executed for each processor. To prevent solutions of low fitness from appearing in the next generation, strings below the average fitness are saved in the tabu list. If best fitness of the GA is not changed for several generations, TS operators are executed for the upper $10\%$ of the population to enhance the local searching capabilities. With migration operation, best string of each node is transferred to the neighboring node after predetermined iterations are executed. For parallel computing, we developed a PC cluster system consists of 8 PCs. Each PC employs the 2 GHz Pentium IV CPU and is connected with others through ethernet switch based fast ethernet. To show the validity of the proposed method, proposed algorithm has been tested with a practical distribution system in Korea. From the simulation results, we can find that the proposed algorithm is efficient for the distribution system service restoration in terms of the solution quality, speedup, efficiency and computation time.

• Journal of Korean Academy of Nursing Administration
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• v.9 no.1
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• pp.129-139
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• 2003

Purpose : The purpose of this study is to investigate the actual condition and recognition about social service activity(SSA) of nurses. Methods : This is a descriptive study. The data were collected by a structured questionare from July 15 to 31, 2002. The questionares were sent to 711 nurses of 38 hospitals, and 664 cases were returned. The answer rate is 93.4%. The data were analyzed by SPSS 11.0. Results : 1. 71.0% nurses had a SSA experience during university, but only 14.2% nurses are participated in SSA now. 2. In the case of having an experience, 56.0% nurses participated in SSA under 1 year, 69.5% nurses didn't support the service costs. 3. In the case of not having experience, the main reason why they didn't participate in is to lack of opportunity. 4. 91.1% nurses recognize the necessity of SSA and 99.5% nurses agree with the necessity of operation system. 82.9% nurses approve the cooperation system among the regions. 87.2% nurses have an intension to participate in SSA when the cooperation system is set up. Conclusion : It need to set up the social service operating system among the regions, and encourage nurse to participate in the SSA.

• Journal of Advanced Navigation Technology
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• v.21 no.5
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• pp.423-427
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• 2017

The IMO approved e-navigation strategy implementation plan made e-navigation adoption visible. In addition, the schedule for the modernization of GMDSS by the ITU was confirmed at the 4th NCSR meeting. Accordingly, we will complement the existing communication system and provide the requirements for the new communication system to be introduced in the future, reflecting all the requirements for the communication system capable of supporting the e-navigation service. Although the communication method for supporting e-navigation service should be capable of providing IP-based data communication basically, it is impossible to provide internet service because of the narrow-band characteristic in the MF/HF frequency bands. In addition, as the existing GMDSS satellite communication service organization expands and new services are introduced, IP based data communication service will be possible, but service restriction resulting from expensive communication cost can be solved by introducing VSAT service.

• The Journal of the Korea Contents Association
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• v.5 no.2
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• pp.257-266
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• 2005

As developing of the internet and computer technology, more interests are gathered to the conference service which provides capability of multi-party real-time visual conference. In this paper, we have designed and implemented a SIP-based visual conference system which includes Presence service. The elements of this conference system are user system, which has conference UA(User Agent) capability, presence seuer and conference server. For the presence service, we have adapted publication method which uses SIP PUBLISH message, and with this service various status informations of users are easily acquired. Also invitations and involvements to the conference are easily made through this service. For the conference server which controls establishment and management of multi-party connections, we have included conference event package. This package provides dynamically changing conference informations and users informations through SIP subscription and notification functions.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.12C
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• pp.1251-1264
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• 2002

Currently, audio streaming services such as on-demand service and live service support only a limited number of clients. They also suffer from a lack of stability and degradation of service quality due to their inefficient use of network resources. Futhermore, since the streaming services usually do not consider dynamic services, they are very inconvenience to use. In order to resolve these drawbacks, we propose a novel audio streaming system based on MPEG-2 AAC file format which are facilitated with the network bandwidths efficiently. The proposed system supports QoS for audio streaming as well as guarantees a stability while streaming service is undergoing. Moreover, the system provides a dynamic interface which enables us to use the streaming service more easily and to manage streaming servers with convenient manner. On the contrary, most of the current available static interface streaming services are mainly depending only on a single fixed web page between client and server, which in consequence lead us to use unflexible static service environment. Our implementation results show the proposed system improves the performance compared to those of the currently existing systems that use MP3 file format. It also provides some benefits such as a stability of service and a easy to management of streaming servers.

• Journal of Digital Convergence
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• v.10 no.11
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• pp.203-208
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• 2012

In this study the hospitality industry's leading companies, hotel companies affect the relationship between the performance information system, customer orientation, service orientation, to identify the target. Convenience extraction methods to Employees engaged in hotel in Seoul & Busan sampling was investigated. In order to derive the results of the study, the study hypothesis was based Information System for customer orientation service orientation, affect the relationship between the performance was investigated. Service orientation and customer orientation significantly affected, but the results of the hypothesis testing, the usefulness of information system technology acceptance model for ease of service orientation and customer orientation in the not significantly affect was not. Service orientation and customer orientation, business performance, but significant results derived significant personal achievements the results derived were not.

• Industrial Engineering and Management Systems
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• v.9 no.3
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• pp.285-293
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• 2010

To obtain visible and traceable information from the supply chain, HW/SW standards for the EPC global network, which process electronic product code (EPC) data read from Radio frequency identification (RFID) tags, are regarded as the de facto industry standard. Supply chain participants install information service systems and provide logistics information to partners by following the EPCglobal architecture framework. Although quality of service (QoS) is essential for providing dependable and scalable services as pointed out by Auto-ID Lab, only a few models for the performance analysis of QoS-related work have been developed in the context of EPC information service systems. Specifically, doing so allows alternative design choices to be tested in an easy and cost-effective manner and can highlight potential performance problems in designs long before any construction costs are incurred. Thus, in this study we construct a model of an EPC information service system for the purposes of performance analysis and designing a dependable system. We also develop a set of building blocks for analytical performance models. To illustrate how the model works, we determine the characteristics of an EPC information service system and then select a combination of these proven modeling concepts. We construct a performance model that considers the response time and shows how to derive meaningful performance values. Finally, we compare the analytical results to measurements of the EPC information service system.

• Korean Security Journal
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• no.61
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• pp.163-179
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• 2019

The purpose of this study is to analyze the effect of service quality of security safety system users on corporate image and customer satisfaction. To confirm this through empirical analysis, a survey was conducted on about 200 users nationwide for about 40 days from May 2 to June 12, 2019. The survey was composed of "service quality, corporate image and customer satisfaction". The empirical analysis was conducted mainly on the analysis of importance, reliability, validity and correlation. This study used SPSS WIN 18.0 to calculate structural equations and exploratory factors. The research results are as follows: The users of the security safety system showed that the better the service quality, the better the corporate image. The better the corporate image, the higher the customer satisfaction. Also, the better the service quality, the higher the customer satisfaction. Therefore, each security safety system company should steadily improve the service quality to improve customer satisfaction.

• Journal of Fashion Business
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• v.14 no.2
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• pp.27-41
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• 2010

The purpose of this study is to investigate the relationship between service orientation of fashion organization and employee's customer orientation. For this study, salespersons in clothing stores were selected as the subjects. We used 4 factors SERV*OR Scale: service leadership, human resource management, employee's empowerment, service system as an organizational service orientation. The results are as follows: First, Service Orientation of the company in fashion field affects the employee's customer orientation. In other words, a fashion company with a higher service orientation will have employees with a higher customer orientation. Second service orientation factors revealed differences depending on the store. Department stores had no effect on factors such as employee's empowerment, service system, but agency stores and outlet stores had effects on all factors. This influential factor is created due to the difference in fashion distribution. Human resource management especially seemed to carry weight among the factors in all stores. So, first and foremost fashion companies should make efforts on education, training of employee.

• Journal of Korea Multimedia Society
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• v.7 no.8
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• pp.1162-1169
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• 2004

This paper implemented the web service that converts general web page to the web page using the speech recognition and the web service consumer that provides speech recognition service for the web page. This system has the web service consumer, the web service provider that converts the web page and the web service provider that provides speech recognition. The web service provider that converts the web page analyzes general web page by using the regular expression and converts it to the speech-recognition web page. The speech recognizer is the web service providers that implemented in the previous study. As a result of experiment, we show that this system changes web page by analyzing tags and extracts hyperlink.