• Industrial Engineering and Management Systems
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• v.12 no.3
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• pp.274-280
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• 2013

This paper proposes a space merging approach to studying the queuing models with finite buffers and jump priorities. Upon the arrival of a call with low priority, one call of such kind is assumed to be transferred to the end of the queue of high priority calls. The transfer probabilities depend on the state of the queue of the heterogeneous calls. We developed the algorithms to calculate the quality of service metrics of such queuing models, and the results of the numerical experiments are shown.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.19 no.1
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• pp.56-65
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• 1994

As a method to control the congestion, priority mechanism which gives two-level priority to various traffics using CLP bit in cell haeder is carried in ATM network. In this paper, we proposed PBS(partial buffer sharing) mechanism with two threshold for provide three-level priority using CLP bit and Res. bit. By performance analysis proposed mechanism, we knew that provides flexibility to satisfy requirements of various quality of service, compare to existing mechanism with two-level priority.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.7 no.1
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• pp.15-23
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• 2003

ATM networks provide the various kinds of service which require the different Quality of Services(QoS) such as loss and delay. By statistically multiplexing of traffics and the uncertainty and fluctuation of source traffic pattern, the congestion may occur. The leaky bucket scheme is a representative policing mechanism for preventive congestion control. In this paper, we analyze the HOL(Head-of-Line) priority leaky bucket scheme. That is, traffics are classified into real-time and nonreal-time traffic. The real-time traffic has priority over nonreal-time traffic for transmission. For proposed mechanism, we obtain the system state distribution, finally the loss probability and the mean waiting time of real-time and nonreal-time traffic. The simple numerical examples also are presented.

• Proceedings of the IEEK Conference
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• 2002.07c
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• pp.1594-1597
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• 2002

In this paper, we proposed the IEEE 802.11 CSMA/CA protocol with the priority scheme. The IEEE 802.11 CSMA/CA protocol is the standard in wireless LAN We applied the proposed method to the aeronautical mobile telecommunication environment. The CSMA/CA protocol has two frames : one is PCF frame for real time service like voice and image and the other DCF frame for contention services like data transmission. Now we proposed the priority scheme that has the different CW region according to the transmitted data. The simmulation results shows the proposed method's performance is improved, Because the collision probability is reduced by allowing the different CW between stations. And the time dalay results show the priority scheme is very appropriated.

• Convergence Security Journal
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• v.11 no.1
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• pp.3-10
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• 2011

This paper proposes DPA(Dynamic Priority Assignment) MAC protocol to improve the traffic QoS on the HFC-CATV(Hybrid Fiber Coax CAble TeleVision) network. In results, DPA MAC protocol is the best performance compare with to IEEE 802.14a MAC in mean request delay, mean access delay. Also, the paper prove a reliability of proposed protocol through comparison between performance analysis and simulation result of DAP MAC protocol.

• International conference on construction engineering and project management
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• 2015.10a
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• pp.687-688
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• 2015

The objective of identifying the cause of inconsistency in determining priority of educational facility maintenance, any related factors were thoroughly identified and tested, to see if it has any effect on decision-making process in resource allocation for educational facilities. On the assumption that 'the more there are to be repaired/maintained and deferred, the higher the relevant cost will be, this will lead to a significant social loss. Accordingly, this study established a framework of determining resource allocation priority based on deferred maintenance and its related expenses. For doing so, it was required to determine relative ranking in terms of resource allocation within a pre-assigned school district, in consideration of the criticality of each deferred maintenance attribute/variable.

• Journal of Satellite, Information and Communications
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• v.1 no.1
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• pp.40-47
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• 2006

The next-generation mobile communication system are required to provide high-data-rate and high quality transmission over hostile radio channels. Orthogonal Frequency Division Multiplexing(OFDM) technique regarded as a most promising solution in mobile environment. This paper considers the issue of efficient subcarrier allocation for OFDM system in multi-service application. Proposed algorithm can consider channel gain of each service and divide subchannel. Proposed method considers priority of service and divide more subchannels in high priority service. When proposed algorithm compares with existent algorithm, the convergence rate improves and the calculation amount is decreased.

• The Journal of the Korea Contents Association
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• v.6 no.3
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• pp.1-11
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• 2006

With the improvement of information telecommunication technology, the various service in broadband integrated services digital networks have a wide range of delay, delay jitter and cell loss probability requirements according to traffic specification. Therefore, the design of appropriate control schemes that can satisfy the cell loss, delay requirements with various traffic specification for B-ISDN is an extremely important challenging problem. In this paper, we propose a priority control scheme using a window counter and a cell counter per each type of class. In the proposed priority control scheme, for satisfying required service quality, we performed the priority control scheme using the delay/loss factors obtained by comparing window counter with cell counter. The performance of proposed control scheme is estimated by computer simulation. In the results of simulation, we verified that the proposed method satisfied per class requirements as the results showed that cell loss probability has a order of video, data, voice and delay time has a order of video, voice and data.

• Journal of Digital Convergence
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• v.19 no.9
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• pp.75-81
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• 2021

The purpose of this research is to derive and evaluate priorities for critical factors that must be determined before an enterprise adopts a cloud computing service. AHP analysis techniques were used to reflect decisions made by experts as research methods. AHP is a decision-making technique that expresses complex decision-making problems hierarchically and derives the best alternatives through pairwise comparison between the items of the hierarchy. Compared to the existing statistical decision making techniques, the decision making process is systematic and simple, making it easy to understand. In addition, the procedure is also reasonable by providing an indicator to determine the consistency of the decision maker in the analysis process. The analysis results of this research showed that security was the first priority, reliability was the second priority, and economic efficiency was the third priority. Among the factors in the first-priority security items, the access control rights and the safety factors of external threats are the most important factors. Research results can be used as a guideline in future practice, and it is necessary to evaluate, compare and analyze the satisfaction of companies that have adopted cloud computing services in the future.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.17 no.5
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• pp.29-41
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• 2014

Ecosystem services provide various benefits to human beings, but are considered to be free of cost. To protect ecosystems in an economically sustainable way, several developing countries have adopted a policy known as the Payment for Ecosystem Services (PES) that compensates upstream services with monetary incentives collected from service users. Vietnam is one of the countries that have enacted a nationwide PES policy. However, the policy in Vietnam requires further development in order to evaluate the spatial priority zones based on the quantification of ecosystem services. To obtain a recent and high-quality land cover map, we first classified the land cover in the Da River basin, in northern Vietnam, using Landsat dataset. We then applied a water balance theory and an USLE equation to assess hydrological ecosystem services concerning water supply and sediment retention. Following the assessment, we identified the priority areas for hydrological ecosystem services exclusively for forest environments. We found that the quantity and distribution of services from forests varied, due to the topography, climate, and land cover. According to a quantile distribution, Mt. Phu Luong, Mt. Fansipan, and Hoang Lien National Park were evaluated as high service areas in terms of both water yield and sediment retention. As a result, this assessment method can help construct spatial priority zones concerning ecosystem service distribution, and can also contribute to benefit sharing by indicating which forest and landowners require compensation.