• ETRI Journal
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• v.32 no.2
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• pp.255-264
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• 2010

Interference scenarios and methodologies between a terrestrial mobile service (MS) system and mobile-satellite service (MSS) system in a co-channel environment are established. Taking into account a practical deployment situation for both systems, we perform computational simulation of interference in terms of carrier-to-interference ratio (C/I) and interference-to-noise ratio (I/N) to evaluate the cofrequency interference from an MS system into an MSS system, and from an MSS system into an MS system, respectively. The methodology and results can be used as a guide when planning the deployment of MSS and MS systems with no unacceptable interference impact between them.

• Proceedings of the Korea Inteligent Information System Society Conference
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• 2001.01a
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• pp.198-201
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• 2001

Recently the wireless-internet has been spreading extensively. People are spending a large part of their time gaining access to information using a mobile device. With the rapid growth of on-line Electronic Commerce, the use of mobile devices creates a new paradigm that provides users with location-independent real time service. Although this new paradigm does have some advantages, limited process speed, low bandwidth, the low battery capacity of mobile devices, and a high rate of wireless network errors causes many overhead expenses during service time with the server. In this paper, we suggest an autonomous service delivery system, which provides mobile agent capability to users that cannot maintain a connection. We have developed the system based on java mobile agent technology. Using this system, we can provide more effective service to users when the user is sending requirements for service through a mobile device that has limited resources. Furthermore we can manage the contact server dynamically when new services are added.

• The Journal of Information Systems
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• v.18 no.3
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• pp.211-229
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• 2009

Recently, trends of information technology development include offerings of service for personalization, intelligence, and convergence. The research suggested a new tour system that tourists can make their tour packages by applying Semantic Web technology. The system includes ontologies and inference rules for offering intelligent and personalized service. Our system called MYT (Make Your Tour-package) was successfully demonstrated by employing realistic scenarios. Current version of the MYT system needs manager's intervention to link and integrate automatically ontology subsystem and Web service. In further study, the MYT will be extended to the system including a component integrating automatically subsystems and a component capturing and processing context data from RFID/USN.

• Journal of Digital Convergence
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• v.5 no.2
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• pp.83-90
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• 2007

Recently, RFID has emerged as the main technology in the logistic services. When the existing recognition technology based on bar codes brings about lots of problem due to its own limits. RFID becomes the center of attention to solve them. However, RFID is not without any obstacles: companies have their own operating systems, while RFID is developed regardless of each company's special features. RFID middleware system based on web service is expected to remove these obstacles. This paper shows how to operate the middleware based on web service and to lay in the DB the tag informations taken from reader system. Middle assures that companies adopting RFID system for their logistic service are given adaptability to any systems whatsoever, available by way of defining logistic information, tag information and reader information. For this purpose, we implement as the basic web service a middleware system that turns all data into XML(eXtensible Markup Language) of SOAP (Simple Object Access Protocol), the standard data.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.30 no.1
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• pp.33-40
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• 2007

A multi-server queueing system with finite buffer is considered. The input flow is the BMAP (Batch Markovian Arrival Process). The service time has the PH (Phase) type distribution. Customers from the BMAP enter the system according to the discipline of partial admission. Besides ordinary (positive) customers, the Markovian flow (MAP) of negative customers arrives to the system. A negative customer can delete an ordinary customer in service if the state of its PH-service process belongs to some given set. In opposite case the ordinary customer is considered to be protected of the effect of negative customers. The stationary distribution and the main performance measures of the considered queueing system are calculated.

• Proceedings of the Korea Contents Association Conference
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• 2008.05a
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• pp.99-103
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• 2008

Recently, the mRFID which combines RFID system a mobile uses infra of mobile communication and it provides object information service with the form which is various. Currently, many object information service system exists. But such system object information is by a service box and becomes the inclusion in specific territory and connection it does from different territory, there is a difficult problem point. It secured the weak point of object information service system of existing from the dissertation which it sees and the object information service system which is suitable in application development of the mRFID it embodied.

• Journal of Service Research and Studies
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• v.10 no.3
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• pp.55-66
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• 2020

This study was attempted to demonstrate the service performance of non-face-to-face real-time video lecture service conducted in the coronavirus crisis in early 2020. Lecture service is divided into service production and service delivery from a service system perspective, and its role of lecture service system and the relationship between lecture service benefits and service satisfaction perceived by learners is demonstrated. In order to demonstrate this structural impact relationship, the result of analysis through a questionnaire survey on a total of 268 undergraduate students at G University, showed that the role and level of the non-face-to-face real-time video lecture service system affects the service convenience and service satisfaction. In the additional analysis, the learning orientation learners group perceived the service system level or role in the lecture service and the service benefit itself higher than the relationship orientation learners group. In the past, when a face-to-face class was conducted, learners group who attended a lot of extra curriculum activities perceived the benefits of coronavirus prevention lower than those of a group that did not. In this way, it is necessary to supplement the lecture service system by identifying the role expectation in the lecture service for the high relationship orientation group and the preferring extra curriculum activity group after detail research.

• Proceedings of the Korean Institute of Communication Sciences Conference
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• 2004.11a
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• pp.301-301
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• 2004

• Journal of the Korean Operations Research and Management Science Society
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• v.37 no.4
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• pp.73-93
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• 2012

In recent years, service delivery systems employing a self-service approach have been rapidly spreading. Since a self-service system provides a lower product price, it attracts more customers. However, some system managers are still hesitant to accept a self-service system, because there is no systematic model to predict its performance. Therefore, this research attempts to provide a systematic and quantitative model to predict the performance of a self-service system, focused specifically on a self-service gas station. Under this model, the traditional queuing theory was adopted to describe the general self-service process, but it is also assumed that some changes occur in both the customer arrival rate and the service performance rate. In particular, the price elasticity was introduced to capture the change in the customer arrival rate, and the existence of learning effect and helpers were assumed to design the changed service performance rate. Under these assumptions, a simulation model for a self-service gas station is established, and three performance measurements, such as average number of customers, average waiting time, and Utilization are observed, depending on the changes in price difference and helper-operating time. In this research, the optimal operation strategy for price differentiation and helper-operating time is proposed in accordance with the level of the customer learning rate. Although this research confines the scope of the study to the self-service gas station model, the results of this research can be applied to any type of self-service system.

• Journal of the Korean Society of Food Culture
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• v.11 no.1
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• pp.13-21
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• 1996

To find out the reference data of the school food service system, I serveyed four primary schools in Seoul, Korea and Nara, Japan respectively. The school children and their parents of whom arbitrary selected two classes among each primary school, were taken the questionaire about the present school food service system and their favorate food. The results were as follows; 1) 74.8% of Korean and Japanese children, and 92.5% of their parents were in favor of school food service. 2) Korean childrin wanted more amount of food and less salty taste. 3) Korean and Japanese children and their parents believed that the school food service system correct children's unbalanced diet. 4) Korean children wished more kinds of foods, western-styled cooking and that the food would be served in warm state. 5) Korean parents wanted that school food service system should be natural and better quality food material, and teacher should educate good eating habit. 6) Korean school children prefer yogurt, cuttle-fish, chicken, bean-curd, tomato, orange, dried laver, sweet potato, pine-mushroom in each food group. In conclusion, school food service system should be enough to meet children's good nutrition status, and the menu would be selected with consideration of children's preference and Korean traditional diet habit. Good table manner and eating all kinds of foods should be targht by school food service system as well as preparing good quality of food.