• KSII Transactions on Internet and Information Systems (TIIS)
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• v.9 no.6
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• pp.1996-2013
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• 2015

This paper considers a scenario that more D2D users exist in the cell, they compete for cellular resources to increase their own data rates, which may cause transmission interference to cellular users (CU) and the unfairness of resource allocation. We design a resource allocation scheme for selfish D2D users assisted by cooperative relay technique which is used to further enhance the users' transmission rates, meanwhile guarantee the QoS requirement of the CUs. Two transmission modes are considered for D2D users: direct transmission mode and cooperative relay transmission mode, both of which reuses the cellular uplink frequency resources. To ensure the fairness of resource distribution, Nash bargaining theory is used to determine the transmission mode and solve the bandwidth allocation problem for D2D users choosing cooperative relay transmission mode, and coalition formation game theory is used to solve the uplink frequency sharing problem between D2D users and CUs through a new defined "Selfish order". Through theoretical analysis, we obtain the closed Nash bargaining solution under CUs' rate constraints, and prove the stability of the formatted coalition. Simulation results show that the proposed resource allocation approach achieves better performance on resource allocation fairness, with only little sacrifice on the system sum rates.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.1
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• pp.308-324
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• 2018

HTTP adaptive streaming (HAS) is a promising technology for delivering video content over the Internet. HAS-based video streaming solutions rely on bandwidth estimation to select the appropriate video bitrate. Video streaming solutions that consider network conditions provide users with seamless video playback. However, when multiple clients compete for a common bottleneck link, conventional bandwidth estimation schemes that consider only one client overestimate the network bandwidth due to the ON-OFF traffic pattern. The bandwidth overestimation can cause Quality of Experience (QoE) degradation, such as unnecessary changes in video quality, and unfairness of video quality. In this paper, we propose a client-side bandwidth estimation scheme to obtain a better QoE of HAS in the multiple-client environment. The proposed scheme differentiates the client buffer status according to the buffer occupancy, and then estimates the available network bandwidth based on the buffer status and segment throughput. We evaluate the performance of HAS implemented in the ns-3 network simulator. Simulation results show that compared with the conventional schemes, the proposed scheme can enhance the QoE.

• Communications for Statistical Applications and Methods
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• v.16 no.4
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• pp.557-572
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• 2009

This article examines the financial soundness of the government employee pension system(GEPS). We use a model that simplifies the existing GEPS considering survival probability distribution of the life of employees. Two approaches were selected for the research: One is the expected net value of pension for an individual employee and the other is the default probability of the system from Monte-carlo simulation. The outcome reveals following three possibilities. First of all, the individual expected net value presents unfairness between the retiree's premium and the benefit he/she receives. Secondly, the Monte-carlo simulation suggests that the default is highly likely to happen in less than 30 years. Thirdly, the governmental reserve and subsidy for GEPS should be required to a certain degree in order to alleviate the probability of default less than 5 percent for the next 30 years.

• Korean journal of communication and information
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• v.16
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• pp.108-135
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• 2001

This study examines the structure of the problems of Korean newspaper reporting raised by the civil society. Based on the differences in the mode of presentation, the problems of newspaper reporting were classified into three types; prominent, associated, and isolate problem. The relations among these problems were defined as the degree of co-occurrence in the monitoring articles. A network analysis was conducted to examine the structure of the problems in Korean newspaper reporting. A $33{\times}33$ similarity matrix of the problems was created by analyzing the data from one monitoring report and two weekly media critics newspapers. The results showed that of the 33 problems, most of them were mentioned as prominent or associated problems. The problems related to the news contents were mostly treated as prominent ones, while the problems about the news writing and reporting styles were frequently treated as associated ones. The network structure of newspaper criticism based on the co-occurrence of 33 problems were divided into six clusters. Among them, the most central was the group including the problems of "unfairness,' "biased interpretation," and "vagueness". In addition, the problems were found to have different roles in the network. Of the 33 problems, two were liaisons and four were attached isolates, indicating the hierarchical structure of problems in newspaper reporting. These results were discussed in the light of two viewpoints; the absence of objective criteria in media criticism, and the need for the comparisons of the current study's results with the opinions of newspaper readers and journalists. finally, the implications for the future studies were presented.

• Journal of Advanced Navigation Technology
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• v.14 no.2
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• pp.253-259
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• 2010

Wireless mesh network is flexible network like Ad hoc network or bluetooth together based on base station. But, wireless mesh network shows high packet loss and when TCP was created, however as it was design based on wired link, wireless link made more transmission error than wired link. It is existent problem of TCP congestion control algorithm that TCP unfairness and congestion collapse over wireless mesh network. When TCP operation occurs with the packet loss where is not the congestion loss, it brings the performance degradation which is serious. In this paper, in order to improve efficient TCP congestion control algorithm in wireless mesh network, we proposed that TCP can adaptively regulate the congestion window in wireless link.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2007.10a
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• pp.91-94
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• 2007

In the IEEE 802.11 Wireless Local Area Networks (WLANs), network nodes experiencing collisions on the shared channel need to backoff for a random period of time, which is uniformly selected from the Contention Window (CW). This contention window is dynamically controlled by the Binary Exponential Backoff (BEB) algorithm. The BEB scheme suffers from a fairness problem and low throughput under high traffic load. In this paper, I propose a new backoff algorithm for use with the IEEE 802.11 Distributed Coordination Function.

• The KIPS Transactions:PartC
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• v.11C no.1
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• pp.89-98
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• 2004

AQM (Active Queue Management) techniques such as RED (Random Early Detection) which be proposed to solve the congestion of internet perform congestion control effectively for TCP data. However, in the situation where TCP and UDP share the bottleneck link, they can not solve the problems of the unfairness and long queueing delay. In this paper, we proposed an simple queue management algorithm, called PSRED (Protocol Sensitive RED), that improves fairness and decreases queueing delay. PSRED algorithm improves fairness and decreases average queue length by distinguishes each type of flow in using protocol field of packets and applies different drop functions to them respectively.

• Journal of Arbitration Studies
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• v.23 no.1
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• pp.85-105
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• 2013

The entertainment industry has developed along with current Korean wave fever, and so entertainment-related disputes are increasing rapidly. Litigation is a poor fit for entertainment disputes because of characteristics such as temporal sensitivity. Thus, in the US, the entertainment industry resolves these disputes through ADR mechanisms like arbitration, but cases of settling such disputes through arbitrations are very rare in Korea. This study examined the characteristics and types of entertainment disputes and considered the compatibility of arbitration as a method for settling disputes, and then suggested tasks for revitalizing arbitration systems as entertainment dispute resolution procedures. Arbitrations have many merits, such as the rapid pace of procedures, confidentiality, satisfying the long-term desires of business relationships, the low cost of settling disputes, judgments rendered by experts, etc.; thus, it is a very suitable mechanism to settle entertainment-related disputes. The study proposes necessary steps for revitalizing arbitration systems for entertainment disputes. First, awareness of entertainment industry workers about the arbitration system should be raised. Second, special educational programs for members the of Korean Commercial Arbitration Board related to entertainment should be set up and operated together with encouraging positive attitudes toward actions like establishing a dedicated arbitration unit on entertainment disputes. Third, neutral, professional arbitrators should be secured and aggressive disclosures made. Fourth, a professional ADR organization such as an "Entertainment Arbitration Committee" should be established.

• Journal of Korean Academy of Fundamentals of Nursing
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• v.3 no.2
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• pp.235-246
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• 1996

The purpose of this study was to discover the experience of hemodialysis which clients confronted hemodialysis at the same time as CRF diagnosis and to understand the nature and meaning of their crisis experience. The research subjects were 6 clients receiving hemodialysis in Seoul from Jan. 1996 to Jul. 1996. Data were collected by informal indepth interview and participant observation. Content Analysis(by Seaman & Verhonick, 1982; Woods & Catanzaro, 1988) was applied to collect similar contents and common experience in order to derivate concepts and categories for better understanding of their hemodialysis experience. As a result, 6 categories derivated to indentify their hemodialysis experience of the CRF clients-confronted hemodialysis at the same time as CRF diagnosis-were as follows: 1) The category of shocking crisis composed the concepts of shock, amagement and suffocation. 2) The category of denial composed the concepts of disease refusal and hemodialysis refusal. They repeatedly visited hospitals or didn't visit hospital in order to refuse disease, then depended on folk remedy or shamanistic method. 3) The category of severe anxiety composed the concepts of abandoned feeling, shame, resentment, neurosis and anger. 4) The category of depression composed the concepts of grief, suffering of unfairness, tearing, desire to death. 5) The category of powerlessness composed the concept of hopelessness. 6) The category of resigned acceptance composed the concepts of resignation and acceptance. In this study, the CRF clients who confronted hemodialysis at the same time as CRF diagnosis experienced six stages in accepting hemodialysis but these stages were mingled simultaneously and went on.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.14 no.5
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• pp.1139-1145
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• 2010

Wireless mesh network is similar to ad-hoc network, so when transferred to the data packet in the wireless environment, interfered factor arise. When TCP(Transport Control Protocol) was created, however as it was design based on wired link, wireless link made more transmission error than wired link. It is existent problem that TCP unfairness and congestion collapse over wireless mesh network. But packet losses due to transmission errors are more frequent. The cause of transmission error in wireless ad-hoc network may be inexactly regarded as indications of network congestion. And then, Congestion Control Algorithm was running by this situation causes the TCP performance degradation. In this paper, proposed TCP can adaptively regulate the congestion window through moving node in the Wireless Mesh Network. And it enhanced the performance.