• 제목/요약/키워드: traffic conditions

검색결과 1,345건 처리시간 0.033초

인공위성 원격탐사의 활용: 선박 감시 기법 (Space-based Ocean Surveillance and Support Capability: with a Focus on Marine Safety and Security)

  • 양찬수
    • 해양환경안전학회:학술대회논문집
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    • 해양환경안전학회 2006년도 춘계학술발표회
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    • pp.41-45
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    • 2006
  • From the 1978 Seasat synthetic aperture radar(SAR) to present systems, spaceborne SAR has demonstrated the capability to image the Earth's ocean and land features over broad areas, day and night, and under most weather conditions. The application of SAR for surveillance of commercial fishing grounds can did in the detection of illegal fishing activities and provides more efficient use cf limited aircraft or patron craft resources. In the area of vessel traffic monitoring for commercial vessels, Vessel Traffic Service (VTS) which uses the ground-based radar system has some difficulties in detecting moving ships due to the limited detection range cf about 10 miles. This paper introduces the field testing results of ship detection by RADARSAT SAR imagery, and proposes a new approach for a Vessel Monitoring System(VMS), including VTS, and SAR combination service.

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Full-scale investigation of wind-induced vibrations of a mast-arm traffic signal structure

  • Riedman, Michelle;Sinh, Hung Nguyen;Letchford, Christopher;O'Rourke, Michael
    • Wind and Structures
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    • 제20권3호
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    • pp.405-422
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    • 2015
  • In previous model- and full-scale studies, high-amplitude vertical vibrations of mast-arm traffic signal structures have been shown to be due to vortex shedding, a phenomenon in which alternatingly shed, low-pressure vortices induce oscillating forces onto the mast-arm causing a cross-wind response. When the frequency of vortices being shed from the mast-arm corresponds to the natural frequency of the structure, a resonant condition is created causing long-lasting, high-amplitude vibrations which may lead to the fatigue failure of these structures. Turbulence in the approach flow is known to affect the cohesiveness of vortex shedding. Results from this full-scale investigation indicate that the surrounding terrain conditions, which affect the turbulence intensity of the wind, greatly influence the likelihood of occurrence of long-lasting, high-amplitude vibrations and also impact whether reduced service life due to fatigue is likely to be of concern.

A traffic and interference adaptive DCA algorithm with rearrangement in microcellular systems

  • Kim, Seong-Lyun;Han, Youngnam
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 1995년도 춘계공동학술대회논문집; 전남대학교; 28-29 Apr. 1995
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    • pp.724-728
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    • 1995
  • A new dynamic channel assignment (DCA) algorithm with rearrangement for cellular mobile communication systems is suggested. Our DCA algorithm is both traffic and interference adaptive, which is based on the mathematical formulation of the maximum packing under a realistic propagation model. In developing the algorithm, we adopt the Lagrangean relaxation technique that has been successfully used in the area of mathematical programming. Computational experiments of the algorithm reveal quite encouraging results. Although our algorithm primarily focuses on microcellular systems, it can be effectively applied to conventional cellular systems under highly nonuniform traffic distributions and interference conditions.

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대도시 도로교통 소음 예측 연구 (Study on the prediction of urban road traffic)

  • 여운호
    • 소음진동
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    • 제6권2호
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    • pp.253-259
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    • 1996
  • Neighboring buildings which are sufficiently close to both sides of an urban street reflect sound back to the road and sound energy is increased by thses reflectors. Therefore, this study is forcussed on the prediction modeling for road traffic noise under reflective conditions. A part of a block in urban road is regared as a box. The sound energy density in the box is employed to establish prediction formulas in terms of independent variables. The variables. The validity of the proposed prediction method has been experimentally confirmed by applying it to actually measured road traffic noise data. On the whole, the agreement between measured and predicted noise levels appeared to be satisfactory.

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도로기초에서 교통 및 환경하중에 의한 비선형 현장 응력 거동 평가 (Evaluation of Traffic Load and Moisture-Induced Nonlinear In-Situ Stress on Pavement Foundation Layers)

  • 박성완;황규영;안동석;정문경;서영국
    • 한국지반공학회:학술대회논문집
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    • 한국지반공학회 2009년도 춘계 학술발표회
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    • pp.11-16
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    • 2009
  • Better understanding of in-situ mechanical behavior of pavement foundations is very important to predict long-term effects on the system performance of transport infrastructure. In order to do that, resilient stiffness characterization of geomaterals is needed to properly adopt such mechanistic analysis under both traffic and environmental loadings. In this paper, in situ monitoring data from KHC test road was used to analyze the non-linearity of stress conditions under traffic and moisture loadings. Then, the predicted non-linear response using finite element method with a selected constitutive model of foundation geomaterials are verified with the field data.

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적응 청크 알고리즘 기반 멀티미디어 스트리밍 알고리즘 (Flexible Multimedia Streaming Based on the Adaptive Chunk Algorithm)

  • 김동환;김정근;장태규
    • 대한전기학회논문지:시스템및제어부문D
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    • 제54권5호
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    • pp.324-326
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    • 2005
  • An adaptive Chunk algorithm is newly devised and a collaborative streaming is designed for high quality multimedia streaming service under time varying traffic conditions. An LMS based prediction filter is used to compensate the effect of time varying background traffic of the WAN. The underflow is generated for the $20\~28\%$ of the data stored in the central server by applying the FARIMA(Fractional Autoregressive Integrated Moving Average) traffic modeling method. The proposed algorithm is tested with the MPEG-2 video files and compensates $71\~85\%$ of central stream underflow.

중소도시 지능형 교통계획(ITS) 사용자 서비스 및 시스템 구축에 대한 연구 (A Research on the Construction of ITS(Intelligent Transport Systems) and User Service in Small Cities)

  • 김용범
    • 대한안전경영과학회지
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    • 제8권5호
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    • pp.151-166
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    • 2006
  • To solve the traffic problems of small cities like Chung Ju City, electronic communications equipment and the introduction of advanced technologies are being used or promoted. Other local areas with developed systems in place are being investigated for applicability. Systems like these will be introduced. This system will embody an organized, efficient transportation and safety system within this study At the moment, to solve the problem of reoccurring traffic in small towns in our country, we must develop an ITS service. We are now in the process of selecting and establishing the most adaptable ITS service to a small city For this purpose, we have studied existing records; taken a poll of the citizens of Chung Ju; examined present traffic conditions, examined road capacities; and reviewed available means of transportation. To accomplish the purpose of a thesis like this, we will research and analyze developed nations' and domestic cities' existing systems, construction and operation. We are in the process of building an ITS System which is the most adaptable to a small city like Chung Ju.

Traffic Analysis of a CAN-based Control System

  • 김대원
    • 전기전자학회논문지
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    • 제5권1호
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    • pp.35-42
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    • 2001
  • This paper deals with an architecture of network-based control system using the CAN(Controller Area Network) protocol and its traffic analysis. It is difficult to determine an optimal network-based control architecture for a specific AGV(Autonomous Guided Vehicle) system with a manipulator arm. The fixed number of periodic messages to be occurred is pre-defined in the system. To determine whether the proposed system architecture is effective or not, we perform traffic analysis for the real-time communication of all messages. Through simulations, the range of transmission speed is found satisfying required conditions and the permissible number of additional sensors is investigated for improving the system performance, when the sampling periods of analog sensors are determined under fixed condition that the transmission speed is over 500Kbps.

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영해관리를 위한 인공위성 원격탐사기술 (Space-based Ocean Surveillance and Support Capability: with a Focus on Marine Safety and Security)

  • 양찬수
    • 해양환경안전학회:학술대회논문집
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    • 해양환경안전학회 2007년도 춘계학술발표회
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    • pp.127-132
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    • 2007
  • From the 1978 Seasat synthetic aperture radar(SAR) to present systems, spaceborne SAR has demonstrated the capability to image the Earth's ocean and land features over broad areas, day and night, and under most weather conditions. The application of SAR for surveillance of commercial fishing grounds can aid in the detection of illegal fishing activities and provides more efficient use of limited aircraft or patrol craft resources. In the area of vessel traffic monitoring for commercial vessels, Vessel Traffic Service (VTS) which uses the ground-based radar system has some difficulties in detecting moving ships due to the limited detection range of about 10 miles. This paper introduces the field testing results of ship detection by RADARSAT SAR imagery, and proposes a new approach for a Vessel Monitoring System(VMS), including VTS, and SAR combination service.

  • PDF

Designing Real-time Observation System to Evaluate Driving Pattern through Eye Tracker

  • Oberlin, Kwekam Tchomdji Luther.;Jung, Euitay
    • 한국멀티미디어학회논문지
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    • 제25권2호
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    • pp.421-431
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    • 2022
  • The purpose of this research is to determine the point of fixation of the driver during the process of driving. Based on the results of this research, the driving instructor can make a judgement on what the trainee stare on the most. Traffic accidents have become a serious concern in modern society. Especially, the traffic accidents among unskilled and elderly drivers are at issue. A driver should put attention on the vehicles around, traffic signs, passersby, passengers, road situation and its dashboard. An eye-tracking-based application was developed to analyze the driver's gaze behavior. It is a prototype for real-time eye tracking for monitoring the point of interest of drivers in driving practice. In this study, the driver's attention was measured by capturing the movement of the eyes in real road driving conditions using these tools. As a result, dwelling duration time, entry time and the average of fixation of the eye gaze are leading parameters that could help us prove the idea of this study.