• Title/Summary/Keyword: priority mechanism

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An Adjustment Algorithm for Bandwidth Grant Interval of UGS Class in IEEE 802.16/WiBro Systems (IEEE 802.16/WiBro 시스템에서의 UGS 클래스 대역폭 할당 주기 조정 알고리즘)

  • Baek, Joo-Young;Yoon, Jong-Pil;Lee, Jeong-Yoon;Suh, Young-Joo
    • Journal of KIISE:Computing Practices and Letters
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    • v.15 no.5
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    • pp.370-374
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    • 2009
  • In this paper we propose an adjustment algorithm for bandwidth grant interval of UGS class flows the overload status of certain frames occurs due to the pre-defined grant interval mechanism of UGS class. In IEEE 802.16/WiBro systems, UGS class is the highest priority to guaranteed QoS Parameters. However, existing grant interval mechanisms of UGS class do not consider the condition that the grant interval of multiple UGS class flows overlaps with certain frames, and thus it causes the overload status in the system. Therefore, the system cannot be guaranteed QoS for UGS class flows. In this paper, we show the occurrence of the problem through simulation studies and propose an adjustment algorithm to solve the problem. Our simulation results show that there is performance improvement in the proposed algorithm. We expect that the real system in which the proposed scheme is applied can provide more stable QoS services by reducing the delay problem that occurs due to the occurrence of the existing grant interval problem of UGS class.

Implement of High Available Replicate Systems Based on Cloud Computing (클라우드 컴퓨팅 기반의 고가용성 복제시스템의 구현)

  • Park, Sung-Won;Lee, Moon-Goo;Lee, Nam-Yong
    • 전자공학회논문지 IE
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    • v.48 no.4
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    • pp.61-68
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    • 2011
  • As business management has a high level of dependence on Informational Technology (IT), protecting assets of a company from disaster is one of the most important thing that IT operating managers should consider. Because data or information is a major source of operation of the company, data security is the first priority as an aspect of continuity of business management. Therefore, this paper will realize disaster recovery system, which is suspended because of disaster, based on cloud computing system. Realized High Available Replicate System applied a method of multi thread target database to improve Replicate performance, and real time synchronize technology can improve efficiency of network. From Active to Active operation, it maximizes use of backup system, and it has a effect to disperse load of source database system. Also, High Available Replicate System realized consistency verification mechanism and monitoring technique. For Performance evaluation, High Available Replicate System used multi thread method, which shows more than threefold of replicate performance than single thread method.

Handling Of Sensitive Data With The Use Of 3G In Vehicular Ad-Hoc Networks

  • Mallick, Manish;Shakya, Subarna;Shrestha, Surendra;Shrestha, Bhanu;Cho, Seongsoo
    • International Journal of Internet, Broadcasting and Communication
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    • v.8 no.2
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    • pp.49-54
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    • 2016
  • Data delivery is very challenging in VANETs because of its unique characteristics, such as fast topology change, frequent disruptions, and rare contact opportunities. This paper tries to explore the scope of 3G-assisted data delivery in a VANET within a budget constraint of 3G traffic. It is started from the simple S_Random (Srand) and finally reached the 3GSDD, i.e., the proposed algorithm. The performance evaluation of different algorithms is done through the two metrics delivery ratio and average delay. A third function utility is created to reflect the above two metrics and is used to find out the best algorithm. A packet can either be delivered via multihop transmissions in the VANET or via 3G. The main challenge is to decide which set of packets should be selected for 3G transmissions and when to deliver them via 3G. The aim is to select and send those packets through 3G that are most sensitive and requiring immediate attention. Through appropriate communication mechanism, these sensitive information are delivered via VANET for 3G transmissions. This way the sensitive information which could not be transmitted through normal VANET will certainly find its destination through 3G transmission unconditionally and with top priority. The delivery ratio of the packets can also be maximized by this system.

Drinking behaviors and policies to reduce harms caused by alcohol use and health promotion policy (건강증진 관점에서 본 음주와 음주폐해 감소 정책)

  • Kim, Kwang Kee;JeKarl, Jung;Lee, Ji Hyun
    • Korean Journal of Health Education and Promotion
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    • v.33 no.4
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    • pp.21-34
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    • 2016
  • Objectives: This is to review drinking behavior and policies to reduce harms caused by alcohol use in Korea and to discuss their implications from a health promotion perspective. Methods: A purported selection was made to include extant literature on drinking behaviors and alcohol control policies into this review. For drinking behaviors reports of national health statistics were used while reports of alcohol control policies submitted to public institutes/organizations were selected for review. Results: Alcohol consumption per capita indicates stable trends over the last two decades. However, percentages of drinkers with high risk drinking over time vary; men remains stable while female appears to increase. Relatively, a few data and/or reports were available about harms derived from alcohol use. Although there are alcohol policies being cost-effective to deal with alcohol related harm in Western society, few alcohol policy available in Korea of being effective, cost-effective with respect to reduction of harms associated with alcohol use. Conclusions: Policy emphasis should be shift from drinkers to availability of alcohol to reduce alcohol related harms with taking health in all policies into consideration. Both statutory mechanism and public acceptance should be of high priority in putting recommended alcohol policy into action.

A Study on the Counterplan for the Reinforcement of Port State Control - Primarily on the Korean Shipping Companies - (항만국통제 강화에 따른 우리나라 해운기업의 대응방안에 관한 연구)

  • Choi. U.;Shin, H.W.;Pyo, H.Y.;Choi, Y.R.
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.9 no.1
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    • pp.1-15
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    • 2003
  • A recent trend of global shipping industry adopting Port State Control (PSC) system is recognized as a proficient mechanism in preventing maritime accident and protecting marine environment. Disadvantages of Korean shipping companies in PSC inspection are unavoidable as Tokyo MOU imposed priority listed flag to Korea Having stated above, appropriate research and prompt preparation in compliance with current PSC requirements for the Korean shipping companies have become an immediate need The objectives of this study are: First, to review in understanding of PSC in overall and foundation of enforcement. Second, to study interaction of international treaties regarding PSC. Third, to compare practical compliance among the countries and to open up a case study on Korean shipping companies in adopting PSC Last, to suggest direction to the Korea shipping companies the most proficient way in compliance with the current Tokyo MOU requirement.

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Hybrid Link State Update Algorithm in QoS Routing (하이브리드 QoS 라우팅 링크 상태 갱신 기법)

  • Cho, Kang Hong
    • Journal of the Korea Society of Computer and Information
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    • v.19 no.3
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    • pp.55-62
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    • 2014
  • This paper has proposed Hybrid QoS Routing Link State Update(LSU) Algorithm that has had a both advantage of LSU message control in periodic QoS routing LSU algorithm and QoS routing performance in adaptive LSU algorithm. Hybrid LSU algorithm can adapt the threshold based network traffic information and has the mechanism that calculate LSU message transmission priority using the flow of statistical request bandwidth and available bandwidth and determine the transmission of the message according to update rate per a unit of time. We have evaluated the performance of the proposed algorithm and the existing algorithms on MCI simulation network using the performance metric as the QoS routing blocking rate and the mean update rate per link, it thus appears that we have verified the performance of this algorithm that it can diminish to 10% of the LSU message count.

The Local Council Members' Attitudes to the Health Policy (지방의회의원들의 보건정책에 대한 인식)

  • 김병익;배상수;조형원
    • Health Policy and Management
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    • v.9 no.2
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    • pp.55-76
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    • 1999
  • In order to understand the local council members' attitudes to the health policy, we conducted mail surveys using self-administered questionaire for 2 months(February and March. 1995). The study subjects were 2.312 local council members in Korea, but only about 11% among whom. 257 persons, responded to 2 times mail survey. This response rate revealed that the local council members was not interested in health care fields. The main results were as follows; The respondents thought that the economic and income development was most important among 15 regional policy agendas and the health care was the 5th or 7th important agenda. They. who had more health needs of and poor access to health care, tended to think that the health care was more important. They considered lobbying to and persuading the civil servants as the best method to tackle the local health care policy agenda. The respondents, who had poor access to health care facilities. tended to set the highest priority for the expansion of public and private health care resources. They expected that the election of local governor would activate the public health program more than thought that the program was implemented more actively than other region. The main opinion of respondents was that the central government had to take over planning and financing for the public health program, and the basic local government had to implment the program and budgeting. The majority of respondents agreed the private dominant medical care delivery system and nation-wide uniformed financing mechanism. Over 60% of them suggested that they were ready to suffer environmental pollution inducing health hazards for the purpose of regional economic and income development. About 75% of them favour the campaign for antismoking regardless of reducing local government's revenue from sale tax.

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Identification of Hepatotoxicity Related Genes Induced by Hexachlorobenzne (HCB) in Human Hepatocellular Carcinoma (HepG2) Cells

  • Kim, Youn-Jung;Choi, Han-Saem;Song, Mee;Song, Mi-Kyung;Ryu, Jae-Chun
    • Molecular & Cellular Toxicology
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    • v.5 no.3
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    • pp.179-186
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    • 2009
  • Hexachlorobenzene (HCB) is a bioaccumulative, persistent, and toxic pollutant. HCB is one of the 12 priority of Persistent Organic Pollutants (POPs) intended for global action by the United Nations Environment Program (UNEP) Governing Council. POPs are organic compounds that are resistant to environmental degradation through chemical, biological, and photolytic processes. Some of HCB is ubiquitous in air, water, soil, and biological matrices, as well as in major environmental compartments. HCB has effects on various organs such as thyroid, bone, skin, kidneys and blood cells and especially, revealed strong toxicity to liver. In this study, we identified genes related to hepatotoxiciy induced by HCB in human hepatocellular carcinoma (HepG2) cells using microarray and gene ontology (GO) analysis. Through microarray analysis, we identified 96 up- and 617 down-regulated genes changed by more than 1.5-fold by HCB. And after GO analysis, we determined several key pathways which known as related to hepatotoxicity such as metabolism of xenobiotics by cytochrome P450, complement and coagulation cascades, and tight junction. Thus, our present study suggests that genes expressed by HCB may provide a clue for hepatotoxic mechanism of HCB and gene expression profiling by toxicogenomic analysis also affords promising opportunities to reveal potential new mechanistic markers of toxicity.

Performance Evaluation and Optimization of Dual-Port SDRAM Architecture for Mobile Embedded Systems (모바일 내장형 시스템을 위한 듀얼-포트SDRAM의 성능 평가 및 최적화)

  • Yang, Hoe-Seok;Kim, Sung-Chan;Park, Hae-Woo;Kim, Jin-Woo;Ha, Soon-Hoi
    • Journal of KIISE:Computing Practices and Letters
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    • v.14 no.5
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    • pp.542-546
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    • 2008
  • Recently dual-port SDRAM (DPSDRAM) architecture tailored for dual-processor based mobile embedded systems has been announced where a single memory chip plays the role of the local memories and the shared memory for both processors. In order to maintain memory consistency from simultaneous accesses of both ports, every access to the shared memory should be protected by a synchronization mechanism, which can result in substantial access latency. We propose two optimization techniques by exploiting the communication patterns of target applications: lock-priority scheme and static-copy scheme. Further, by dividing the shared bank into multiple blocks, we allow simultaneous accesses to different blocks thus achieve considerable performance gain. Experiments on a virtual prototyping system show a promising result - we could achieve about 20-50% performance gain compared to the base DPSDRAM architecture.

Dynamic slot allocation scheme for rt-VBR services in the wireless ATM networks (무선 ATM망에서 rt-VBR 서비스를 위한 동적 슬롯 할당 기법)

  • Yang, Seong-Ryoung;Lim, In-Taek;Heo, Jeong-Seok
    • The KIPS Transactions:PartC
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    • v.9C no.4
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    • pp.543-550
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    • 2002
  • This paper proposes the dynamic slot allocation method for real-time VBR (rt-VBR) services in wireless ATM networks. The proposed method is characterized by a contention-based mechanism of the reservation request, a contention-free polling scheme for transferring the dynamic parameters. The base station scheduler allocates a dynamic parameter minislot to the wireless terminal for transferring the residual lifetime and the number of requesting slots as the dynamic parameters. The scheduling algorithm uses a priority scheme based on the maximum cell transfer delay parameter. Based on the received dynamic parameters, the scheduler allocates the uplink slots to the wireless terminal with the most stringent delay requirement. The simulation results show that the proposed method guarantee the delay constraint of rt-VBR services along with its cell loss rate significantly reduced.