• Title/Summary/Keyword: passive priority

Search Result 43, Processing Time 0.026 seconds

The Number of ONU based Priority Scheduling Mechanism for IPTV Multicast Service (IPTV 멀티캐스트 서비스를 위한 ONU 수 기반 우선순위 스케줄링 기법)

  • Kwon, Young-Hwan;Choi, Jun-Kyun
    • The KIPS Transactions:PartC
    • /
    • v.16C no.2
    • /
    • pp.217-222
    • /
    • 2009
  • This paper proposes the number of Optical Network Unit (ONU) based priority scheduling mechanism over Ethernet Passive Optical Network (EPON) to support multicast Quality of Service (QoS) for Internet Protocol Television (IPTV) service. Multicast QoS is effected by the receivers' number of a packet because multicast efficiency is determined by how many receivers are received multiple copied packets. Therefore, the proposed mechanism assigns a priority with the number of ONUs to allocate high priority to IPTV services used by many people and firstly transmits a packet with high priority. By doing so, we show that the proposed mechanism support favorite IPTV services with better and stable QoS in spite of congestion.

A Passive Traffic Signal Priority Control Algorithm for Emergency Vehicles (긴급차량 우선신호 센터제어 알고리즘 개발)

  • Lee, Jongwoo;Lee, Soong-bong;Lee, Jinsoo;Um, Ki Hun;Lee, Young-Ihn
    • The Journal of The Korea Institute of Intelligent Transport Systems
    • /
    • v.16 no.3
    • /
    • pp.110-119
    • /
    • 2017
  • This study develops a passive traffic signal priority control algorithm for emergency vehicles. The passive priority control estimates and applies signal times for each signalized intersection on the emergency vehicle's route when an emergency call is received. As signals are controlled before the emergency vehicle leaves for its destination, it is possible to clear the queues at each intersection more effectively. Most of the previous studies applied preemption, which ends green time of cross streets when the emergency vehicle arrives at each intersection. This study applies green extension and early green in order not to shift the order of phases, and guarantees minimum green time for each phase. Simulation results show that the delay of emergency vehicles decreases when the signals are controlled. It is expected that delays can be decreased further by integrating the active priority control with the passive priority control algorithm presented in this study.

Development and Application of Passive Climatic Design Tool Using Building Bioclimatic Chart for Energy Efficient Building (건물생체기후도를 이용한 자연형 기후설계 도구 개발 및 활용)

  • Song, Seung-Yeong
    • KIEAE Journal
    • /
    • v.4 no.3
    • /
    • pp.153-160
    • /
    • 2004
  • It is essential to know climatic characteristics of the site for energy efficient building design. However, it is difficult to obtain a climate data. Even though the climate data is obtained, it is difficult to be applied to the building design since it is usually consisted of just series of numbers. Also, designers cannot know the effective climatic design strategies suitable for the site with ease. Thus, this study aims to develope the climatic design tool working on the personal computer operated by windows 95/98/2000/XP. WYEC weather data and building bioclimatic chart are adopted for the climate analysis. Climatic Characteristics(distributions of the dominant factors, bioclimatic needs, needs to each passive design strategy, and the order of priority, etc.) of Seoul are analysed and presented as an example. Also, passive climatic design process making use of this tool is presented.

A Study on the Indicators for evaluating Environmental Sustainability of Building - Focused on evaluating indicators for utilizing natural energy - (건물의 환경적 지속가능성 평가 지표에 관한 연구 -자연에너지 활용 평가지표를 중심으로-)

  • Bang, Jae-Sung;Yang, Byoung-E
    • KIEAE Journal
    • /
    • v.6 no.2
    • /
    • pp.27-34
    • /
    • 2006
  • The purpose of this study is to develop the sustainability indicators for assessing environmental sustainability of building. This reseach focused on evaluating indicators for passive design in the stage of site planning and building massing. In order to achieve the aims of this study, first priority was given to set up systematic framework of sustainability indicators for passive design. Based on the framework, the assessment categories and indicators by each category were established. Secondly, the weighted value of each indicators were obtained by questionnaire survey of the experts. As the result of the analysis of questionnaire of experts, feasible indicators were obtained and the grades of measured values were deduced. Finally, this paper presented comprehensive environmental sustainability indicators which is related to the passive design.

Modified Passive Clustering Algorithm for Wireless Sensor Network

  • AI Eimon Akhtar Rahman;HONG Choong Seon
    • Proceedings of the Korean Information Science Society Conference
    • /
    • 2005.07a
    • /
    • pp.427-429
    • /
    • 2005
  • Energy efficiency is the most challenging issue in wireless sensor network to prolong the life time of the network, as the sensors has to be unattended. Cluster based communication can reduce the traffic on the network and gives the opportunity to other sensors for periodic sleep and thus save energy. Passive clustering (PC) can perform a significant role to minimize the network load as it is less computational and light weight. First declaration wins method of PC without any priority generates severe collision in the network and forms the clusters very dense with large amount of overlapping region. We have proposed several modifications for the existing passive clustering algorithm to prolong the life time of the network with better cluster formation.

  • PDF

Efficient Differentiated Bandwidth Allocation for QoS based Ethernet PON System (QoS 기반의 EPON 시스템에서 효율적인 차등 대역폭 할당)

  • Eom Jong-Hoon;Jung Min-Suk;Kim Sung-Ho
    • Journal of KIISE:Information Networking
    • /
    • v.32 no.2
    • /
    • pp.156-166
    • /
    • 2005
  • Ethernet passive optical network is an economical and efficient access network that has received significant research attention in recent years. A MAC(Media Access Control) protocol of PON, the next generation access network, is based on TDMA(Time Division Multiple Access) basically. In this thesis, we addressed the problem of dynamic bandwidth allocation in QoS based Ethernet PONs. We augmented the bandwidth allocation to support QoS in a differentiated services framework. Our differentiated bandwidth guarantee allocation(DBGA) allocates effectively and fairly bandwidths among end users. Moreover, we showed that DBGA that perform weighted bandwidth allocation for high priority packets result in better performance in terms of average and maximum packet delay, as well as network throughput compared with existing dynamic bandwidth allocations. We used simulation experiments to study the performance and validate the effectiveness of the proposed bandwidth allocations.

Recent Advances in Toxoplasma gondii Immunotherapeutics

  • Lim, Sherene Swee-Yin;Othman, Rofina Yasmin
    • Parasites, Hosts and Diseases
    • /
    • v.52 no.6
    • /
    • pp.581-593
    • /
    • 2014
  • Toxoplasmosis is an opportunistic infection caused by the protozoan parasite Toxoplasma gondii. T. gondii is widespread globally and causes severe diseases in individuals with impaired immune defences as well as congenitally infected infants. The high prevalence rate in some parts of the world such as South America and Africa, coupled with the current drug treatments that trigger hypersensitivity reactions, makes the development of immunotherapeutics intervention a highly important research priority. Immunotherapeutics strategies could either be a vaccine which would confer a pre-emptive immunity to infection, or passive immunization in cases of disease recrudescence or recurrent clinical diseases. As the severity of clinical manifestations is often greater in developing nations, the development of well-tolerated and safe immunotherapeutics becomes not only a scientific pursuit, but a humanitarian enterprise. In the last few years, much progress has been made in vaccine research with new antigens, novel adjuvants, and innovative vaccine delivery such as nanoparticles and antigen encapsulations. A literature search over the past 5 years showed that most experimental studies were focused on DNA vaccination at 52%, followed by protein vaccination which formed 36% of the studies, live attenuated vaccinations at 9%, and heterologous vaccination at 3%; while there were few on passive immunization. Recent progress in studies on vaccination, passive immunization, as well as insights gained from these immunotherapeutics is highlighted in this review.

The Comparison of Activities of Occupational Safety and Health among Sub-Sectors of Manufacturing Industry (제조업의 업종별 안전보건활동 수준 비교)

  • Kim, Ki-Sik;Rhee, Kyung Yong
    • Journal of the Korean Society of Safety
    • /
    • v.29 no.5
    • /
    • pp.136-145
    • /
    • 2014
  • This article has compared the level of activities of occupational safety and health in workplace among sub-sectors of manufacturing industry in order to set the priority for policy intervention. Data of manufacturing industry in the survey on the current status of occupational safety and health was used with factor analysis and radar graphic method. Authors have categorized sub-sectors of manufacturing industry into four categories, attained group, active group, neglected group, and passive group based on injury rate, level of safety and health activities. The neglected group may be the first target group for occupational safety and health policy guiding some detailed occupational safety and health activities. Limitation of this study is that cross sectional data was analyzed. The long term effect could not be analyzed.

Traffic Signal Control Strategy for Passive Tram Signal Priority on City Arterial (도시부 간선도로의 고정식 트램 우선신호를 위한 교통신호운영 전략)

  • Jeong, Young-Je;Kim, Young-Chan;Kim, Dae-Ho
    • The Journal of The Korea Institute of Intelligent Transport Systems
    • /
    • v.10 no.1
    • /
    • pp.27-41
    • /
    • 2011
  • This research proposes new tram signal coordination model, called MAXBAND MILP-Tram for a passive tram signal priority strategy. The proposed model was formulated based on the MAXBAND model that was a traditional arterial signal optimization model. The model could calculate the bandwidth solutions for both general-purpose-lane traffic and median-tram-lane traffic. Lower progression speed are applied for the tram traffic considering lower running speed and dwell time at the stations. A phase sequence procedure determines the green times and left-turn phase sequences for tram traffic in median tram lane. To estimate the performance of the MILP-Tram model, the control delay of trams were estimated using the micro simulation model, VISSIM. The analysis results showed 57 percent decrease of the tram compared to the conventional signal timing model. The delay for car, however, increased 18 percent. The sensitivity analysis indicated that the passive tram signal priority strategy using the offset and phase sequence optimization was effective in reducing the person delay under the congested traffic condition.