• Title/Summary/Keyword: Priority Traffic

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A Study on the Queueing Simulation of Lock Gates according to the Functional Rearrangement in Incheon Port (인천항 기능 재배치에 따른 갑문의 대기 시뮬레이션 연구)

  • Koo, Ja-Yun
    • Journal of Navigation and Port Research
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    • v.31 no.3 s.119
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    • pp.205-212
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    • 2007
  • Due to the construction of Incheon Grand Bridge, there is driven a necessity for rearranging the function of Inner Port with the development of Outer South Port. In this paper, I'd like to simulate the port operation levels of Lock Gate in Inner Port with estimating the traffic volumes of 2011 and 2015, which will reveal the Demurrage Cost and the Accumulation Cost of Freight in Inner Port. Finally I will evaluate the economic movement effects of the container ship's calling from Inner port to South Port/Outer South Port from 2011 to 2015. The results are as followings ; (1) The average utilization of Lock Gates are reduced by $7\sim8$ percentage point. (2) The mean queueing value are saved by 25 percentage point. (3) The Demurrage Cost and the Accumulation Cost of Freight except Lock Gate charges and the Benefit of Routeing Reduction are saved about 800 million Won annually.

An Emergency Message Propagation Method with Stem and Branch Structure for Vehicle Safety Communication (차량안전통신을 위한 줄기와 가지 구조를 이용한 긴급 메시지 전파 방법)

  • Yu, Suk-Dea;Cho, Gi-Hwan
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.32 no.2A
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    • pp.203-212
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    • 2007
  • An advanced vehicle safety system can be constructed by exchanging danger-related information ,such as urgency stop, traffic accident, obstacle, and car trouble, among the vehicles. However, because network topology changes rapidly and frequently due to the mobility of vehicles, it is impossible to configure the network for information forwarding in this environment. In the most of vehicle safety communication applications, an emergency message is propagated in a form of broadcasting. The simple broadcasting causes a lot of problems in terms of efficiency due to multi-hop area and radio collision problem. This paper proposes a method of selective message forwarding with stem and branch structure for propagating the emergency messages. However, the proposed method raise the efficiency of message transmission with the selective forwarding based on the priority assignment as its location. We analyze and evaluate the performance by comparing the proposed scheme with other schemes that are presented in the paper.

A Medium Access Mechanism to Support Urgent Message Transmission (긴급 메시지 전송을 지원하기 위한 매체 접근 기법)

  • Han, Se-Won;Oh, Young-Bin;Sim, Jae-Ki;An, Beoung-Ku
    • The Journal of the Institute of Internet, Broadcasting and Communication
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    • v.10 no.1
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    • pp.97-105
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    • 2010
  • This paper proposes an effective medium access mechanism which is based on IEEE 802.11 to transmit an urgent message, The main features of the proposed mechanism are as follows. First, when it comes to channel access to have high priority, it has a shorter interval between frames than that specified in standard document. Second, we use fixed window size instead of back-off window with an exponential increase. Performance evaluation of proposed mechanism is executed by simulation and compare with the node using the specified mechanism in standard document. Performance evaluation results show that according to increasing competition the nodes using proposed method have less accessing time than the conventional methods. Also, the proposed method can improve processing time because of the decreasing transmission delay.

Development of Revenue Change Index by New Highway Opening Under the Unified Revenue System (통합채산제하의 신규 고속도로 개통으로 인한 통행료수입 변동지표 개발)

  • JEON, Gyoseok;CHUNG, Woohyun;CHOI, Keechoo
    • Journal of Korean Society of Transportation
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    • v.33 no.3
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    • pp.247-255
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    • 2015
  • When the new highway is opened, the new highway has alternative or linkage relationship with current highway networks. This change will lead to the different traffic patterns which can also lead to the change of toll revenue in other surrounding highways. This study investigates the change of revenue on the current highway networks caused by the new highway opening under the unified revenue system. Moreover, this study calculates the effectiveness of the revenue fluctuation when the highway system is under controlled by the public or private institution and proposes the meaning of the revenue fluctuation to those institutions. This study also proposes an index of revenue change that could be used to reflect the individual project evaluation and set the priority between multiple projects. Some limitations and future research agenda have also been discussed.

A Study on Accidents for the Aged (노인에게 발생하는 안전사고에 관한 연구)

  • Park, Sang-Sub
    • The Korean Journal of Emergency Medical Services
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    • v.10 no.1
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    • pp.41-49
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    • 2006
  • Purpose: It can be said that the aged belong to the group vulnerable to safety accidents. The purpose of this study was to investigate safety accidents to old people and provide basic data to prevent them from being in a safety accident. Result : 1. The number of the aged of traffic accident fatalities per 100,000 persons was 57.8, which was significantly higher than other OECD countries. 2. trauma for the aged, falling accounted for 60.6%, which was relatively higher than other wounds, probably because of decreased capacity of movement and reduced faculty of sensation. 3. accidents to the aged at home, 43.9% occurred in a room, which shows great risk of safety accidents to the aged in a room. 4. the aged generally showed negative awareness of social safety. Suggestion : 1. it is necessary to provide regular education about accidents through the mass media and at social welfare facilities in order for aged people to consolidate safety consciousness repeatedly. 2. it is necessary to make a brief and clear guide to prevention of accidents. 3. the Ministry of Construction and Transportation and the Ministry of Health and Welfare should give priority to designing a building for aged people and authorize construction according to the standards for establishing safety facilities for the aged. 4. it is necessary to change social consciousness. since transportation accidents can be caused not by aged people's insufficient safety consciousness but by that of all the people, it is necessary to provide society-wide education programs against dangerous driving in order to guarantee aged people's safety. 5. legal procedure to secure aged people's safety should be strengthened to reinforce legal protection for them.

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Design of General Peripheral Interface Using Serial Link (직렬 링크 방식의 주변 장치 통합 인터페이스 설계)

  • Kim, Do-Seok;Chung, Hoon-Ju;Lee, Yong-Hwan
    • The Journal of Korea Institute of Information, Electronics, and Communication Technology
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    • v.4 no.1
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    • pp.68-75
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    • 2011
  • The performance of peripheral devices is improving rapidly to meet the needs of users for multimedia data. Therefore, the peripheral interface with wide bandwidth and high transmission rate becomes necessary to handle large amounts of data in real time for multiple high-performance devices. PCI Express is a fast serial interface with the use of packets that are compatible with previous PCI and PCI-X. In this paper, we design and verify general peripheral interface using serial link. It includes two kinds of traffic class (TC) labels which are mapped to virtual channels (VC). The design adopts TC/VC mapping and the scheme of arbitration by priority. The design uses a packet which can be transmitted through up to four transmission lanes. The design of general peripheral interface is described in Verilog HDL and verified using ModelSim. For FPGA verification, Xilinx ISE and SPARTAN XC3S400 are used.We used Synopsys Design Compiler as a synthesis tool and the used library was MagnaChip 0.35um technology.

Implementation of QoS-awared MAC Protocol for Home Networks (홈 네트워크를 위한 QOS 보장형 매체접속제어 프로토콜의 구현)

  • 황원주
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.7 no.2
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    • pp.228-238
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    • 2003
  • We believe that existing wire solutions such as HomePNA2.0 using phone lines and HomePlug using power line and wireless solution such as HomeRF are the most promising solutions, because of its cost-effectiveness. However, MAC protocols of these solutions provide only Class of Service(CoS) using priority mechanism like HomePNA and HomePlug or consider only voice among real-time traffics like HomeRF. For these reasons, we perceive the needs of the new MAC protocol which is no new wire solution and provides guaranteed Quality of Service (QoS) for not only voice but also video and audio. In light of this, we present the design and software implementation of a new MAC protocol for Home Networks. Our evaluation results of software implementation verify that proposed MAC protocol can provide low delay, low loss, and low jitter to real-time traffic by reserving bandwidth.

Characterization of Atmospheric Concentrations of Volatile Organic Compounds in Industrial Areas of Pohang and Gumi Cities (포항과 구미의 대규모 산단지역 대기 중 휘발성 유기화합물 농도 분포 특성에 관한 연구)

  • Baek Sung-Ok;Kim Soo-Hyun;Kim Mi-Hyun
    • Environmental Analysis Health and Toxicology
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    • v.20 no.2 s.49
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    • pp.167-178
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    • 2005
  • This study was carried out to evaluate the temporal, spatial, and seasonal variations of VOC, and to characterize the VOC concentrations in two large industrial complexes located in Pohang and Gumi cities. Twenty -four hours continuous sampling of selected VOC was made with STS 25 sequential tube samplers and double-bed adsorbent tubes. Air samples were collected every three hour interval for 7 consecutive days in each site during summer and winter. VOC were determined by thermal desorption coupled with GC/MS. A total of 27 VOCs of environmental concern were determined, including aliphatic, aromatic and halides. Generally. concentrations of toxic VOC were higher in Gumi than Pohang, and VOC levels in industrial areas were typically several-fold higher than those in residential areas. The most abundant VOC appeared to be toluene for both cities. However, chlorinated VOC were higher in Gumi than Pohang, while aromatic VOC were more abundant in Pohang than in Gumi. Two cities showed relatively different variations of VOC concentrations within a day. It is likely that traffic related sources are major factors affecting the VOC in Pohang, and industrial solvents usages are important sources in Gumi. These results imply that the occurrence and levels of atmospheric VOC are strongly dependent on the type of industries in each city. Therefore, in order to develop any control strategies or to establish the priority rankings for VOC in large industrial complexes, the type of industries and the occurrence of VOC in the atmosphere should be taken into consideration.

Transformation Characteristics of Inner Road and Communal Space in Old Settlements of Downtown Cheong Ju (청주 도심 옛마을의 안길과 중심공간의 특성 변화)

  • Chae, Su-Min;Byun, Kyeong Hwa;Kim, Tai Young
    • Journal of the Korean Institute of Rural Architecture
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    • v.14 no.3
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    • pp.93-100
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    • 2012
  • The purpose of this study is to examine the change of inner roads responding to the street system and to examine the how to influence to communal space of village focused on 22 existing old settlements in downtown Cheong Ju. This study examined the types of inner roads based on advanced research. For the research on communal space, interviews with the residents living in the village were conducted to figure out the location and function of it. Also, it was analyzed comparatively with the present communal space. The results are as followings: the width of an inner road has a effect to function of an inner road when flow of an inner road has kept. The function of inner road has been kept when the width of an inner road expanded as pedestrians should be given priority to vehicular traffic. However, the function of inner roads has been changed and the community has been separated when the width of inner roads expanded for vehicular. Because the location of the communal space in the village is affected by the change of the inner road, when the inner road is maintained, the location of the communal space is also maintained, but when the inner road is changed, the location of the communal space is also changed. The communal spaces such as public wells and wash spaces have lost and they have been substituted with senior citizen centers or community centers.

Adaptive Transmission Techniques for the Availability Assurance of Long-distance Radio Link (장거리 무선 링크의 가용도 보장을 위한 적응전송 기법)

  • Youn, Jong-Taek;Kim, Yongi;Lim, Young-Gap;Kim, Young-Ho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.19 no.3
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    • pp.514-522
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    • 2015
  • In Microwave Radio Link, it is necessary to consider the radio fading to consistently assure the radio link of the high quality as the distance. If the fixed modulation is used for the microwave radio link, it is difficult to keep the high availability of link for the case of the long distance. Adaptive Modulation(AM) provide good quality on microwave link, but the application of the only-AM is not enough to provide the availability assurance due to the fluctuating characteristics of link capacity. Our previous study has proposed the improvement method of transmission in association with the distance, however the previous method needed to make up for the common application. There was no suggestion of a mathematical formula with a variable. In this paper, we propose an optimized Adaptive Transmission Techniques with calculating formula of the priority traffic transmission capacity based on AM in consideration of the fade margin for the availability assurance as the distance and the comparison of the channel bandwidth for Long-distance Radio Link.