• Journal of the military operations research society of Korea
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• v.30 no.1
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• pp.107-134
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• 2004

Today's Internet is providing a single service which is so-called "best-effort service". Now, multimedia and real-time applications are not only demanding large bandwidth but also requiring high QoS. For this, MPLS and DiffServ technology can be adopted to support more scalability and QoS for data traffic engineering. The DISN(Defense Information Systems Network) supports CBR service for voice traffic and VBR service for data traffic which is best-effort service. We propose how to adopt MPLS and DiffServ technology to support traffic engineering and guarantee QoS in the DISN. A traffic analysis according to prioritized traffic classes is done using OPNET simulation tool for assuring QoS. The result shows that low priority packets are delayed a little bit, but high priority packets are transferred more efficiently than without traffic engineering.gineering.

• Proceedings of the IEEK Conference
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• 2000.07a
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• pp.525-528
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• 2000

According to the development of B-ISDN on ATM network, the uses of Multimedia service is growing. Although ABR service uses the network resource most effectively because it is able to change the transfer rate, it is not used for multimedia service until recently. In this paper, we set priority queue and non-priority queue in the ATM switch and each queue has threshold so is can be adopted in different transfer rate method. We propose the real-time traffic transfer method over ABR service based on an effective traffic control method.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.35 no.4
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• pp.162-170
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• 2012

We propose a new priority discipline called the strict T-preemptive priority discipline, and derive the waiting time distributions of each class in the strict T-preemptive priority M/G/1 queue. Using this queueing analysis, we evaluate the performance of an opportunistic spectrum access in cognitive radio networks, where a communication channel is divided into time slots, a licensed primary user is assigned to one channel, and multiple unlicensed secondary users may opportunistically exploit time slots unused by the primary user. We also present a numerical example of the analysis of the opportunistic spectrum access where the arrival rates and service times distributions of each users are identical.

• Journal of the Korea Society of Computer and Information
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• v.25 no.1
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• pp.159-165
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• 2020

In spite of various studies on the service quality of customer center, the previous studies are mainly focused on the studies on the relationship between customer satisfaction and loyalty, rather than on the evaluation model of service quality. In this study, we reviewed the service quality of customer center factors discussed in previous studies and developed a hierarchical model for measuring customer service quality based on Brady and Cronin's (2001) model. The first level consists of interaction (process) quality, physical environment (system) quality, and outcome quality, and the second level consists of kindness, positiveness, professionalism, systematic, convenience, accessibility, accuracy, promptness, and reliability. In addition, based on the developed hierarchical model, the priority of each factor that customer center users consider important is analyzed by AHP methodology. As a result, the interaction quality was important in the first level, and professionalism, kindness, and accuracy were important in the second level. Such a study can be a guideline for establishing a standard for evaluating the service quality of customer center or for managing more importantly in practice.

• Journal of Information Technology Services
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• v.14 no.3
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• pp.99-116
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• 2015

The concept of Cloud computing has been introduced in the IT field over 10 years and industry has been expanding constantly. However, compare to the maturity of global market, Korea cloud computing industry is only in the early stage. Even the Korea has advantages in technology infrastructure; the pace of Korea cloud computing market growth is taking a serious downturn. Under these circumstances, it is needed to be discussing that strategy for expanding the cloud computing market size and for sustaining global competitiveness of local companies. Previous studies on plans for Korea cloud computing market has been conducted since 2009 and most of them are tend to examined in demand perspective. Thus, this study aims at identifying the priority of business challenges for making better performance in the market with service provider aspects. To analyze the important factors in the providing cloud computing service, ANP methodology was applied in this study. The network model including five clusters, security, stability, performance, consumer, and institution, was defined through literature review and expert survey was conducted to collect data. As a result of ANP analysis, 'Securing service reliability' was analyzed as the most important factor and followed by 'Preparing the range of legal liability', 'Preventing personal information leakage' and 'Preventing confidential information data leakage.' The priority of result indicates that service provider needs to focus on to make the secured service environment. This study has significance on analyzing the priority of business challenges in the service provider perspective. This study will provide useful guidelines to for establishing strategies in cloud computing market.

• Korean Journal of Community Nutrition
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• v.5 no.3
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• pp.529-536
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• 2000

The major purpose of this study was to identify the differences in priorities of nutrition service needs between the service provider and consumers (general population). Identification of the personal characteristics which influence the priorities of nutrition service needs among the general population was also examined. An interview survey using a questionnaire was conducted to collect the data required for analysis. The questionnaire included the priorities of various nutrition service needs as well as the personal characteristics of the study subjects. The study subjects were 300 residents over 40 years of age, and 15 health workers representing health center service personnel in Kyounggi province. Wilcoxon Rank Sums test were adopted to analize the differences in priority between the service providers and consumers. The results showed that priority of nutrition service needs for provider were significantly different from that of consumer. Gender, age, family type, and education levels of the population were the significant factors affecting the differences in priorities for nutrition service needs among consumers (general population). Out of the results, it could be suggested that consumers need should be considered in developing nutrition services to promote nutrition services utilization in health centers. The results may also suggest that one of the causes for the low utilization rate of nutrition services in health centers was the provider oriented program development regardless of the needs of consumers.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.28 no.11A
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• pp.859-866
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• 2003

In this paper, we designed the bandwidth allocation scheme with priority consideration for upstream channel access of EthernetPON. The objective of our scheme is to control the multi services in more effective way according to their CoS(Class of Service) or QoS(Quality of Service). The designed scheme considers transmission priority in the both side of OLT and ONU. In the OLT's view, the Two-step scheduling algorithm is applied with which we can support multiple bandwidth allocation policies simultaneously, i.e. SBA for the time-sensitive, constant rate transmission services and DBA for the best-effort services. This Two-step scheduling algorithm reduces the scheduling complexity by separating the process of transmission start time decision from the process of grant generation. In the ONU's view, the proposed scheme controls 8 priority queues of the 802.1d recommended 8 service classes. Higher priority queue is serviced in prior during the allowed GATE time from OLT. The OPNET modeling and simulation result compares the performance of each bandwidth allocation policy with SBA or DBA only approach.

• The Journal of the Korea Contents Association
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• v.20 no.2
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• pp.105-113
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• 2020

The development and application of cultural technologies(CT) are expected to lead to create various service scenarios and business models. Considering the wide range of application and extensibility of CT, it is necessary to design multidimensional evaluation methods for priority of the support of R&D budgets. The method should include the various evaluation criteria such as economic feasibility and user benefit of service made by a cultural technology. Our research addresses priority decision for fosterage of cultural technologies using fuzzy TOPSIS. Seven evaluation attributes are used to compare five specific technologies. Based on the results, service usefulness is the most important factor among the evaluation attributes. Also, technologies of computer graphics and UI/UX have higher priority than the others. We expect our research to help to provide guidelines for selection of promising cultural technologies which foster the culture and contents industry.

• The KIPS Transactions:PartC
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• v.8C no.6
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• pp.793-805
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• 2001

In the recent priority system, high-priority packet will be served first and low-priority packet will be served when there isn\`t any high-priority packet in the system. By the way, even high-priority packet can be blocked by HOL (Head of Line) contention in the input queueing System. Therefore, the whole switching performance can be improved by serving low-priority packet even though high-priority packet is blocked. In this paper, we study the performance of preemptive priority in an input queueing switch for high speed switch system. The analysis of this switching system is taken into account of the influence of priority scheduling and the window scheme for head-of-line contention. We derive queue length distribution, delay and maximum throughput for the switching system based on these control schemes. Because of the service dependencies between inputs, an exact analysis of this switching system is intractable. Consequently, we provide an approximate analysis based on some independence assumption and the flow conservation rule. We use an equivalent queueing system to estimate the service capability seen by each input. In case of the preemptive priority policy without considering a window scheme, we extend the approximation technique used by Chen and Guerin [1] to obtain more accurate results. Moreover, we also propose newly a window scheme that is appropriate for the preemptive priority switching system in view of implementation and operation. It can improve the total system throughput and delay performance of low priority packets. We also analyze this window scheme using an equivalent queueing system and compare the performance results with that without the window scheme. Numerical results are compared with simulations.

• Journal of Korean Institute of Industrial Engineers
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• v.25 no.1
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• pp.130-140
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• 1999

This paper deals with a priority queueing model in an ATM system. Two types of customers are considered. Type-1 customers have push-put priority over type-2 customers. Type-1 customers can enter the service only when the number of type-2 customers is less than a threshold T. We derive the joint probability of the number of customers in the buffer, the mean waiting time, and the loss probabilities of each type. We also propose an optimal control policy that satisfies a given quality of service.