• The Journal of Korean Institute of Communications and Information Sciences
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• v.33 no.6A
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• pp.624-634
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• 2008

The mobile station which is about to do handover in IEEE 802.16e networks scans its neighboring base station channels to decide its next target base station. However, due to the lack of location information of its subscribers, the serving base station cannot provide any reliable candidate channel which is actually attachable by the scanning mobile stations, which makes the mobile station suffer from the long scanning time. Sometimes, long scanning time may cause the degradation of quality of service due to repeatable scan-duration or failure to start the handover procedure in time. To overcome these problems, in this paper, we propose a new protocol so called fast group scanning scheme, in which multiple mobile stations form a group to scan their neighboring base station channels simultaneously. Main contribution of this proposal is to find and decide a reliable target base station within a short scanning time. The fast group scanning scheme can be deployed to the cell network of the serving base station with a dynamic neighboring base station list management.

• Journal of Korean Society for Quality Management
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• v.46 no.4
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• pp.923-938
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• 2018

Purpose: O2O service are becoming popular in various industries such as food delivery and taxi. This research explores how users' motivation of O2O service influence customer loyalty through expectation-confirmation and satisfaction. this study attempts to explore the motivation factor (i.e. pricing, enjoyment, immediately, social influence) and to empirically examine the relationships between those and users' loyalty to O2O service. Methods: To test the proposed research model, a survey research methodology was used. Paper survey was distributed to O2O service users in Korea. A total of 198 data were used for the analysis. Structural equation modeling was used to test hypotheses. Results: According to our findings, this study found that satisfaction was positively influenced by users' motivation factors. all hypotheses about the effect of motivation on expectation-confirmation were statistically not significant. Conclusion: O2O service providers should consider the results of this study to satisfy users' expectations and satisfaction for building a better O2O market.

• Journal of Korean Society for Quality Management
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• v.46 no.4
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• pp.797-820
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• 2018

Purpose: It is to seek for an appropriate cost rate analysis methodology of credit card value propositions in Korea. For this issue, it is claimed that methodologies based on probability distribution is more suitable than methodologies based on data-mining. The analysis model constructed for the cost rate estimation is called VCPM model. Methods: The model includes two major variables denoted as S and P. S is monthly credit card usage amount. P stands for the proportion of usage amount at special merchants over the whole monthly usage amount. The distributions assumed for P are positively skewed distributions such as exponential, gamma and lognormal. The major inputs to the model are also derived from S and P, which are E(S) and the aggregate proportion of usage amount at special merchants over the total monthly usage amount. Results: When the credit card's value proposition is general discount, the VCPM model fits well and generates reasonable cost rate(denoted as R). However, it seems that the model does not work well for other types of credit cards. Conclusion: The VCPM model is reliable for calculating cost rate for credit cards with positively skewed distribution of P, which are general discount card. However, another model should be built for cards with other types of distributions of P.

• Journal of Global Scholars of Marketing Science
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• v.17 no.4
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• pp.113-139
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• 2007

This study aims to, looking from a standpoint of network, has investigated the shipping industry's B2B e-marketplace, the characteristics that can earn electronic trust from the users, and characteristics of the web-site. It has examined the mechanism whereby electronic trust be earned and how it affects web-site involvement and service transaction intention. Ultimately, The study attempts to make proposals whereby such trust can lead for a cooperative trading community in the shipping industry's B2B e-marketplace The Covalence structural equation modeling was designed and empirically tested for the shipping industry's B2B e-marketplace. The shipping industry employees were given questionnaires and data were analyzed. Except for perceived security of the three characteristic factors on the web-site, the perceived site quality and characteristics factors in operation only affected co-variables. Transaction Fairness was determined to be the most important factor among exogenous factors increasing electronic trust. With regards to transaction rules, if a transaction is beneficial only to one side, then no long term transaction will not take place. If the concerned parties properly recognize that transaction fairness is crucial to electronic transaction, then it will enormously contribute to successful operations of shipping e-marketplace. Also, Perceived efficiency in transaction also affects electronic trust. This reduces transaction costs and speeds up and simplifies the transaction process. It has reduced greater time and costs than existing off-line transaction, and would positively affect electronic trust. By making an open forum for participants to obtain information for transaction, they can gather useful information, and at the same time, the web-site operator can provide information, which, in turn, will increase electronic trust in electronic transaction. Furthermore, such formation of trust in electronic transaction influences shipping companies in such a way that they will want to continuously participate in the transaction, raising web-site involvement. The result of increased trust is that shipping companies in the future will do business with each other and form a foundation for continuous transactions amongst themselves. Consequently, the formation of trust in electronic transaction greatly influences web-site involvement and service transaction intention. The results of the study have again proved that in order to maintain continuous business relationship with the current clients, electronic trust in virtual space, which operates the shipping industry's B2B e-marketplace, is important for the interested parties.

• The Journal of Society for e-Business Studies
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• v.18 no.2
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• pp.257-277
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• 2013

Those studies in the field of Management Information Systems and the Success Model of the DeLone and McLean's Information Systems suggest that some factors related to information systems should be developed and operated to affect the performance of the user's personal and companies through the introduction and use of corporate information systems. The purpose of this study is put on searching for some factors which impact on user satisfaction about the customer information management systems of call center. We did conduct on a survey of 539 people who are working as a call center counseling employees as setting up a structural equation model which reflects previous research on working environment and job satisfaction, and modified DeLone and McLean's information system success model. The results of this study are as follows. First, seven of the eleven hypotheses that three quality of the information systems might be affecting working environment, job satisfaction, user satisfaction were adopted Second, we confirmed that the working environment works as a the partial mediation and the quality of services works as a fully mediation between system/information quality and users' satisfaction. The implications of this study are that it is necessary not only to make a good working environment but also to keep improving it in order to boost the operational performance of information systems in the future.

• Journal of the Institute of Electronics Engineers of Korea TC
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• v.47 no.1
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• pp.1-9
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• 2010

In this paper we propose a scheduling algorithm for supporting Quality of Service(QoS) in IEEE 802.11e HCCA referred to as ASR-DRR and ASD-DRR, which aims at providing improved performance for the support of multimedia traffic. Although We identify the problem of the current IEEE 802.11e HCCA (Hybrid Coordination Function Controlled Channel Access) scheduler and its numerous variations, that the queue information cannot be notified to the Hybrid Coordinator (HC) timely, therefore the uplink delay lengthens unnecessarily. We suggests a simple solution and a couple of implementation practices, namely the Adaptive Scheduler with RTS/CTS (ASR) and Adaptive Scheduler with Data/Ack (ASD). They are both further elaborated to emulate the Deficit Round Robin (DRR) scheduler. They are also compared with existing exemplary schedulers through simulation, and shown to perform well.

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.6
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• pp.676-688
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• 2014

The IEEE 802.11e EDCA (Enhanced Distributed Channel Access) mechanism has been proposed to improve the QoS (Quality of Service) of various services in WLANs (Wireless Local Area Networks). By differentiating the channel access delay depending on ACs (Access Categories), this mechanism can provide the relative service differentiation among ACs. In this paper, we consider that WLAN is deployed in medical environments to transfer medical traffic and we reveal that the quality of the medical traffic (in particular, ECG signals) is significantly deteriorated even with the service differentiation by IEEE 802.11e EDCA. Also, we analyze the reason for performance degradation and show that IEEE 802.11e EDCA has difficulty in protecting the transmission opportunity of high-priority traffic against low-priority traffic. In order to assure medical-grade QoS, we firstly define the service priority of medical traffic based on their characteristics and requirements, and then we propose the enhanced channel access scheme, referred to as DIFF-CW. The proposed scheme differentiates CW (Contention Window) depending on the service priority and modifies the channel access procedure for low-priority traffic. The simulation results confirm that the DIFF-CW scheme not only assures the QoS of medical traffic but also improves the overall channel utilization.

• The Korean Journal of Archival Studies
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• no.16
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• pp.201-256
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• 2007

Nowadays Korean main archives and manuscript repositories are planning to develop archival information service for students and teachers in their web sites. This study is aimed at discovering main issues of developing archival information service for students and teachers and finding a solution. The goal of archival information service for students and teachers is the promotion of use through launching service and the gradual growth of archival management program. The customer group is segmented into the students and teachers who are learning and teaching Korean history in classroom. As a result of analyzing curriculum and educational environment, the archival information must be developed into teaching-learning materials. And the processing archival information into archival content is needed. Consequently the character of archival information service for students and teachers is conceptualized as archival content service for teaching-learning materials. At every step of developing archival content service for teaching-learning materials, the next main points are considered and achieved. First, the strategy of customer-focused service must be the same from beginning to end. Second, the growth of traditional archival management(e.g. classification, description and finding aids) must be contributed. Third, the collaboration system leading by professional education staff must be organized. Fourth, the archival information must be related with teaching-learning activities. Fifth, the quality of content is more important than the quantity of it. Sixth, the networking with another agencies for cooperation must be considered.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.31 no.2
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• pp.28-35
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• 2008

Most organizations have recently put more emphasis on the improvement in service quality. This phenomenon could come from the recognition that service quality plays an essential role in enhancing organization's business performance. Hence this paper presents a framework for improving such service quality. The presented framework involves the methodology for (i) developing service quality indices, (ii) measuring and evaluating service quality, (iii) analyzing the level of service quality, (iv) constructing the quality improvement road map, (v) determining the quality improvement action plan. This methodology is intended to create self-sustaining improvement in service quality from the entire organization's perspective. An illustration is also given.

• Journal of Korea Society of Industrial Information Systems
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• v.23 no.4
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• pp.93-105
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• 2018

For some consumer goods, consumers expect additional benefits or returns after purchasing or using them. This kind of consumer goods that consumers expect some additional benefits or returns after consumption (hereafter consumer goods of investment or CGOI) need not only an approach of simple purchasing perspective but also an approach from investment perspective. Current study tries to figure out if consumers react differently in their purchasing intentions toward CGOI between when they focus on the product's quality, functions, or other current state related information (i.e., simple purchase focus) and when they focus on the benefits that will be generated after using the product (i.e., investment focus). According to the results, while consumers' purchasing intentions toward CGOI in the investment mode are greater when the price is low than when the price is high, consumers' purchasing intentions toward CGOI in the simple purchasing mode are greater when the price is hgih than when the price is low.