• Title/Summary/Keyword: priority mechanism

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AHP and Group Decision Making for Access Network Selection in Heterogeneous Wireless Networks (이기종 무선 네트워크에서 접근 네트워크 선택을 위한 AHP와 그룹 결정 방법)

  • Kim, Nam-Sun
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38A no.10
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    • pp.858-864
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    • 2013
  • In the 4G wireless environment, one of the important issues is to discover and select an access network suited for users. In this thesis, we propose a new network selection mechanism using group decision making and evaluate the effect of network selection schemes for vertical handover in heterogeneous wireless networks. We consider the group of users with similar QoS requirements search for the available access network simultaneously and a service area consist of multiple access networks with various characteristics. We divide the access networks with similar characteristics split into a group. Between each group, the one group is selected and within that group, the best access networks will be assigned according to priority order by network selection algorithm. We evaluate and compare the performance of three representative MADM schemes: GRA, SAW and TOPSIS. The MATLAB simulation results indicate the proposed algorithm can make a more effective choice according to the networks' characteristics and user's preference.

Investiagtions on the Etching of Platinum Film using High Density Inductively Coupled Ar/Cl$_2$ HBr Plasmas

  • Kim, Nam-Hoon;Chang-Il kim;Chang, Eui-Goo;Kwon, Kwang-Ho
    • Transactions on Electrical and Electronic Materials
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    • v.1 no.3
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    • pp.14-17
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    • 2000
  • Giga bit dynamic random access memory(DRAM) requires the capacitor of high dielectric films. Some metal oxides films have been proposed as the dielectric material . And Pt is one of the most promising electrode materials. However very little has been done in developing the etching technologoy Pt film. Therefore, it is the first priority to develop the technology for plasma etching of Pt film. In this study, the dry etching of Pt film was investigated in Inductively Coupled Plasma(ICP) etching system with Cl$_2$/Ar and HBr/Cl$_2$/Ar gas mixing. X-ray photoelectron spectroscopy (XPS) was used in analysis of sidewall residues for the understanding of etching mechanism. We found the etch residues on the pattern sidewall is mainly Pt-Pt, Pt-Cl and Pt-Br compounds, Etch profile was observed by Scanning Electron Spectroscopy(SEM) . The etch rate of Pt film at 10%, Cl$_2$/90% Ar gas mixing ration was higher than at 100%. Ar. Addition of HBr to Cl$_2$/Ar as an etching gas led to generally higher selectivity to SiO$_2$. And the etch residues were reduced at 5% HBr/5% Cl$_2$/90% Ar gas mixing ration. These pages provide you with an examples of the layout and style which we wish you to adopt during the preparation of your paper, Make the width of abstract to be 14cm.

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Multi-channel Adaptive SVC Video Streaming with ROI (ROI를 이용한 H.264 SVC 에서의 다중 채널 네트워크 비디오 전송 기법)

  • Lee, Jung-Hwan;Ryu, Eun-Seok;Yoo, Hyuck
    • Journal of Broadcast Engineering
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    • v.13 no.1
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    • pp.34-42
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    • 2008
  • This paper proposes the mechanism which improves the qualify of video on a limited network bandwidth by applying the ROI technique to an H.264 Scalable Extension technique. The network environment assumed in this parer is the next generation network convergence environment in which the mobile device has one or more network interfaces. Therefore, we allocate the priority to video packets as the hierarchy structure of H.264 SVC-encoded video stream and ROI information, and transmit those packets over appropriate network channel for using those multiple network interfaces. This paper shows two experiments first one is extracting and allocating the video stream on an appropriate network channel, second one is unequal packet transmission by allocated priorities (e.g. ROI). Performance evaluations show that this approach delivers an improved decoded video quality when compared with conventional transmission schemes, especially on device which has multiple network interfaces.

A Buffer Management Algorithm based on the GOP Pattern and the Importance of each Frame to Provide QoS for Streaming Services in WLAN (WLAN에서 스트리밍 서비스이 QoS를 제공하기 위한 GOP 패턴 및 프레임 중요도에 따른 버퍼 관리 기술)

  • Kim, Jae-Hyun;Lee, Hyun-Jin;Lee, Kyu-Hwan;Roh, Byeong-Hee
    • 한국정보통신설비학회:학술대회논문집
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    • 2008.08a
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    • pp.372-375
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    • 2008
  • IEEE 802.11e standardized the EDCA mechanism to support the priority based QoS. And the virtual collision handler schedules the transmission time of each MAC frame using the internal back-off window according to the access category(AC). This can provides the differentiated QoS to real-time services at the medium traffic load condition. However, the transmission delay of MAC frame for real-time services may be increased as the traffic load of best effort service increases. It becomes more critical when the real-time service uses a compressed mode video codec such as moving picture experts group(MPEG) 4 codec. That is because each frame has the different importance. That is, the I-frame has more information as compared with the P- and the B-frame. In this paper, we proposed a buffer management algorithm based on the frame importance and the delay bound. The proposed algorithm is consisted of the traffic regulator based on the dual token bucket algorithm and the active queue management algorithm. The traffic regulator reduces the transmission rate of lower AC until that the virtual collision handler can transmit an I-frame. And the active queue management discards frame based on the importance of each frame and the delay bound of head of line(HoL) frame when the channel resource is insufficient.

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The Vertical Handover Between WLAN and UMTS using Group Decision Making Method (그룹결정방법을 이용한 WLAN과 UMTS간의 수직 핸드오버)

  • Kim, Nam-Sun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.9
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    • pp.4492-4497
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    • 2013
  • An important features of next-generation wireless networks will be heterogeneous environment in which a mobile terminal will be able to connect to multiple radio access networks and network selection mechanisms play an important role in ensuring QoS for users in this environment. In this paper, our study is concerned with an extension of the well known AHP to the group decision making methods. The users requested specific QoS divide into a group and the access networks with similar characteristics split into a group. Between each group, the one group is selected and within that group, the best access networks will be assigned according to priority order by network selection algorithm. The experimental results of MATLAB simulation show that the every user in each services can select the same network with decision value as large as 0.9. Consequently, the proposed network selection mechanism is more effective than conventional one in integrated UMTS and WLAN networks.

Environmental Dispute Adjustment System : Current Status and Issues (환경분쟁조정제도의 현황과 과제)

  • Yoon, Esook;Lee, Choon-Won
    • Journal of Arbitration Studies
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    • v.28 no.1
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    • pp.125-151
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    • 2018
  • Rapid industrial growth based on massive fossil fuel energy consumption has caused serious damages on natural environment and every aspects of human life. As demands for clean and pleasant living circumstance increases, conflicts and disputes around environmental problems have also been widespread. Given the 'environmental rights' is a relatively new legal concept, however, resolving environmental disputes through the traditional legal principles and litigation procedures could be restrictive and, in some sense. inefficient as well as expensive. With efforts to develop new legal principles on environmental disputes, the environmental dispute adjustment system has been introduced as an alternative dispute resolution to the traditional legal dispute procedures. The Korean Environmental Dispute Resolution Commission introduced as the environmental dispute adjustment system has been well established for the past twenty-seven years, given the steadily increasing numbers of applications to the Commission over environmental disputes. However, as most cases are still small in money terms and mainly subject to adjudication, the effectiveness and practical contribution of the Commission in the resolution of environmental disputes have in fact been limited. For the enhancement of the status and roles of the Commission as the prior instrument of the alternative dispute resolution(ADR) in environmental disputes, several suggestions could be considered as follows: First, mediation needs to be more activated than adjudication in order to meet the primary purpose of ADR that resolves environmental disputes according to free will of concerned parties. Second, the scope of mediation could be expanded to the areas including potential environmental damages. Third, the roles and responsibilities of the Environmental Dispute Resolution Commissions at both central and local levels need to be evenly distributed. Fourth, the mechanism and procedures of environmental dispute resolution should be standardized. Fifth, the status of the Environmental Dispute Resolution Commission could be elevated in rank by shifting its current affiliation from the Ministry of Environment to the Office of Prime Minister. Sixth, the organizational structure and human resources of the Commission need to be reinforced. Seventh, the current situation that tends to give priority to litigation procedures when an environment dispute is simultaneously pending in litigation and mediation should be eased and properly adjusted. Eighth, the adoption of mandatory mediation in advance to litigation needs to be discussed. Ninth, the legal authority of the Commission's decisions should be further guaranteed. If above suggestions are thoroughly reviewed and properly adopted, the roles, authority and power of the Environmental Dispute Resolution Commission would be increased in the era when environmental conflicts get widespread, requiring an effective alternative environmental dispute resolution mechanism.

Changes of Land-Use Policy in Rural China (1980년대 후반 이후 중국 농촌 토지제도의 변화)

  • Moon, Soon-Cheol
    • Journal of the Korean Geographical Society
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    • v.31 no.3
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    • pp.558-576
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    • 1996
  • Since 1978. China has progressed her reforms of her economy. In this process, refroms in rual area have been operated with top priority. The system of collective economy had been changed into that of private economy. Rural farming and land-use system had been changed also. The household responsibility system took the place of a People's Commune. That was the system that could inspire farm-household with a will to work, and hence, increase the productivity of agriculture. However, with the developement of market mechanism in the later 1980s, that system got inadequate to new situation. For instance, incentives of a will to work slowly decreased, agricultural productivity did not increase, and labor forces were tremendously transferred to non-agricultural sector. This situation created the demand for a new system of rural land policy and use. This paper intends to describe changes of new system of land use in rual China. Those changes are as follows. 1. The system of land-circulation has been spread widely. 2. 'Liangtianzhi' (the system of two kind land-use) divided the land into two kinds, 'kouliangtian' (the land of food) and 'zerentian' (the land of obligation). The one is allocated in proportion to the per capita, and to support farm-household' and function, the other is allocated in proportion to the labor force, in order to increase the commercial function of land. 4. 'Guimojingying' (management of scale): For overcomint the disadvantage of dispersal of land, the relative concentration of land was required. 4. 'Gufenzhi' (a joint-stock system) is practised for the purpose of establishing clear-cut lines of land ownership. 5. 'Sihuangpaimai' (auction the use right of four kinds of wasteland) is for full-using of the wasteland. It can be apprehended that these systems and policies were the process of adaption to market mechanism. In these, rural China could escape form the disorder due to rapid changes, and overcome the existing contradiction.

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lonizing Radiation Hormesis in Crops (저선량 전리방사선에 의한 작물의 활성증진)

  • Kim, Jae-Sung;Lee, Young-Bok
    • Korean Journal of Environmental Agriculture
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    • v.17 no.1
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    • pp.76-83
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    • 1998
  • The most remarkable aspect in the hormesis law is that dose of harmful agents can produce effect that are diametrically opposite to the effect found with high doses of the same agent. Minute quantities of a harmful agent bring about very small change in the organism and control mechanisms appear to subjugate normal processes to place the organism in a state of albert and repair. The stimulated organism in more responsive to changes in environmental factors than it did before being alerted. Routine functions, including repair and defense, have priority for available energy and matetial. The alerted organism utilizes nutrients more efficiently, grows faster, shows improved defense, and lives longer. Accelerated germination, sprouting, growth, development, blooming and ripening, and increased crop yield and resistance to disease are found in plants. Another concept supported by the data in that low doses of ionizing radiation provide increased resistance to subsequent high doses of radiation. The hormesis varies with subject plant, variety, state of seed, environmental and cultural conditions, physiologic function measured, dose rate and total exposure. The results of hormesis are less consistently found, probably due to the great number of uncontrolled variables in the experiments. The general dosage for radiation homlesis in about 100 (10 to 1,000) times ambient or 100 (10 to 1,000) times less than a definitely harmful dose, but these must be modified to the occasion. Although little is known about most mechanisms of homzesis reaction, overcompensation of repair mechanism is offered as one mechanism.

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Changes in patterns of plastic surgery emergencies at a level I trauma center in India during the COVID-19 pandemic

  • Singh, Veena;Haq, Ansarul;Sharma, Sarsij;Kumar, Sanjeev;Kumar, Aditya;Kumar, Amarjeet;Kumar, Neeraj;Kumar, Anil
    • Journal of Trauma and Injury
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    • v.35 no.2
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    • pp.108-114
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    • 2022
  • Purpose: The coronavirus disease 2019 (COVID-19) pandemic has had major effects worldwide, including sudden and forceful setbacks to the healthcare system. The COVID-19 pandemic has also led to changes in the plastic and reconstructive management of emergency cases, including those due to road traffic accidents. This study analyzed changes in patterns of plastic surgery emergencies and modifications in consultation policies to minimize the exposure of healthcare workers. Methods: Data on plastic surgery emergency calls received from the trauma and emergency department were collected for a period of 2 months before and during lockdown. The data were then analyzed with respect to the cause, mechanism, and site of the injury, as well as other variables. Results: During lockdown, there was a 40.4% overall decrease in the plastic surgery emergency case volume (168 vs. 100). The average daily number of consultations before lockdown was 2.8 as compared to 1.6 during lockdown. Road traffic accidents remained the most common mechanism of injury in both groups (45.8% vs. 39.0%) but decreased in number during the lockdown (77 vs. 39). Household accidents, including burns, were the second most common cause of injury in both phases (7.7% vs. 20.0%), but their proportion increased significantly from 7.7.% to 20.0% in the lockdown phase (P=0.003). The percentage of minor procedures done in the emergency department increased from 53.5% to 72.0% during lockdown (P=0.002). Procedures in the operating room decreased by 73.1% during lockdown (67 vs. 18, P=0.001). Conclusions: The COVID-19 pandemic and lockdown orders in India greatly influenced trends in traumatic emergencies as observed by the plastic surgery team at our tertiary care center. Amidst all the chaos and limitations of the pandemic period, providing safe and prompt care to the patients presenting to the emergency room was our foremost priority.

A Case Study on the effects of Elephant Foot Method considering the rate of Changes in Tunnel Cross Section (터널 단면적 변화를 고려한 각부보강 영향성 평가)

  • Lee, Gil-Yong;Oh, Hyeon-Mun;Cho, Kye-Hwan;Oh, Jeong-Ho;Kim, Jong-Ju;Kim, Yong-Seong
    • Journal of the Korean Geosynthetics Society
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    • v.17 no.1
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    • pp.111-118
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    • 2018
  • In case of excavation of the tunnel under weak ground conditions, such as fault zone, leg pile reinforcement with the purpose of suppressing tunnel crown settlement and side wall displacement is commonly applied. There are convergence, crown settlement, leg settlement, and the axial force of leg as a main factor for confirming the safety of support considering the installation angle and length of leg pile reinforcement according to the increase in rate of change of tunnel cross-section. In particular, the influence of right corner settlement, among variables for safety confirmation during excavation, has been analyzed as the dominant factor in the most important priority management showing larger displacement tendency than the increase in rate of the cross-section. And, it was analyzed that the occurrence tendency of axial force on leg pile reinforcement showed the influence of behavior according to the friction support concept mechanism of the pile reinforcement rather than the increase in rate of tunnel cross-section, as it showed a small increase compared to the increase rate of the tunnel cross-section which did not show a great correlation from the viewpoint of the change of the axial force by the length of each leg pile reinforcement with regards to the change in rate of increase in tunnel cross-section. If a certain length of the leg pile reinforcement is selected based on the above grounds, even if the cross-section of the tunnel in poor ground condition is somewhat larger, it has been proved to be a more reasonable method considering the workability and economical efficiency by not extending the length of the leg pile reinforcement by force.