• 제목/요약/키워드: heavy traffic

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Interchange 주변토양의 중금속 농도 분포

  • 이주광;강혜진;강희만;이찬영
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
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    • pp.271-274
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    • 2002
  • Heavy metal concentrations of roadside soils around interchanges were found to decrease as Zn)Cu>Pb and be lower than the legal guideline levels. The concentrations of Cu, Pb and Zn in roadside soils around Kyeong-bu highway interchanges were 1.3 to 1.5 times higher those around Yeong-dong highway interchanges. Difference of heavy metal concentrations in soils seems to be caused by difference of traffic volume between Kyeong-bu and Yeong-dong highway interchanges. This means that contamination of interchange roadside soils mainly depends on traffic volume.

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교통량 과밀 도로주변의 토양과 가로수, 대기중 Pb, Cu, Zn 중금속 농도와 그 상관성에 관한 연구 (Pb, Cu, Zn Contaminants and Their Correlation of Soil, Leave and Bark of Ginkgo. B and Ambient Air Adjacent to a Heavy Traffic Road Side)

  • 박기학
    • 한국환경보건학회지
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    • 제18권2호
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    • pp.19-25
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    • 1992
  • The study was carried out to investigate the correlation between the heavy metals emitted by the motor vehicles with the heavy traffic road side environment (soil, leave, bark, ambient air). The Pb, Cu, Zn contents in road side soil sand leaves, barks from Ginkgo, biloba and ambient air adjacent to the heavy traffic road side from June to August, 1992 Suwon city were analyzed by Atomic absorption spectrometry and Inductively coupled plasma emission spectrophotometry. The results were as follows: 1) The high levels of heavy metals concentration were Pb, at city-terminal in soil (186 $\mu$g/g), Cu, at city-terminal in soil (221 $\mu$g/g), Zn, at city-terminal in ambient air (252 $\mu$g/m$^{3}$). 2) The low leves of heavy metals concentration were Pb, at North-gate in ambient air (1.65$\mu$g/m$^{3}$), Cu, at North-gate in ambient air (4 $\mu$g/m$^{3}$), Zn, at North-gate in ambient air (15.31$\mu$g/m$^{3}$). 3) The regional distribution of Pb, Cu, Zn in road side soils, leaves and barks from Ginkgo, biloba, ambient air show high levels in turn, city4erminal, Guan Sean Dong, South gate, North gate. 4) The concentration of heavy metals (Pb, Cu, Zn) in soils, leaves, barks, ambient air was highly correlated with the traffic volume of the sampling sites (r=0.64~0.96). To conclude that the high levels of Pb, Cu, Zn contaminations were positively related to motor vehicles-borne pollutants and road side soils, trees, ambient air adjacent to a high density building area with low road coverage and heavy traffic volume were reflected strongly by the hazardous pollutants emitted by motor vehicles.

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대설의 경제적 피해 - 교통수요모형과 불능투입산출모형의 적용 (Economic Loss Assessment caused by Heavy Snowfall - Using Traffic Demand Model and Inoperability I-O Model)

  • 문승운;김의준
    • 국토계획
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    • 제53권6호
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    • pp.117-130
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    • 2018
  • Heavy snow is a natural disaster that causes serious economic damage. Since snowfall has been increasing recently, there is a need for measures against heavy snowfall. In order to make a policy decision on heavy snowfall, it is necessary to estimate the precise amount of damage by heavy snowfall. The direct damage of the heavy snow is severe, however the indirect damage caused by the road congestion and the urban dysfunction is also serious. Therefore, it is necessary to estimate indirect damage of snowfall. The purpose of this study is to estimate the effects on the regional economy from the limitation in traffic logistics caused by heavy snow using the transport demand model and inoperability input-output Model. The result shows that the amount of production loss caused by the heavy snow is KRW 2,460 billion per year and if the period of snowfall removal is shortened by one day or two days, it could be reduced to KRW 1,219 or 2,787 billion in production loss.

실내 대기환경과 중금속농도의 분포특성에 관한 연구 - 학교 환경의 중금속농도 (A Study on the Characteristics of Heavy Metal Concentration and Indoor Atmospheric Environments ; Heavy Metal Concentration in School Environments)

  • 박종길;장난심
    • 한국환경과학회지
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    • 제6권5호
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    • pp.451-459
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    • 1997
  • This paper alms to describe the indoor-outdoor air quality in school environment through the analyses of heavy metal concentration by inductively Coupled Plasma(ICPI, which were observed at some school environment, such as traffic area, industrial area seme-industrial area, and residence area. The results are as follows : (1) Regardless Indoor and outdoor, the area with the highest concentration of heavy metal is industrial area followed by traffic area, residence area and semi-industrial area in descending order of magnitude. And the heavy metal concentration of indoor is higher than that of outdoor. (2) The main heavy metal components with more high level concentration of Indoor than those of outdoor are Zn, Al, Ca and these heavy metal concentrations are higher in class than In corridor and outdoor.

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양방향 2차로 도로의 지체시간 산정을 이용한 승용차환산계수 결정이론 (A Mathematical Model for Determination of PCE's Based on Delay for Two-Lane Two-Way Highway)

  • 이승준;최재성
    • 대한교통학회지
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    • 제17권2호
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    • pp.149-162
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    • 1999
  • 양방향 2차로 도로의 설계, 용량 및 운영분석의 단계에서 고려되어야 할 핵심사항으로 화물차와 같은 중차량이 교통류에 미치는 영향을 들 수 있다. 중차량이 교통류에 미치는 영향은 승용차환산계수로 표현할 수 있으며, 이는 교통류 운영분석의 주 MOE's로 사용되는 교통량, 운행속도, 지체시간, 주행의 자유 등에 대하여 중차량이 미치는 영향을 계산하여 승용차 몇 대에 해당하는가를 나타낸 것이다. PCE환산에 있어서 중요한 것은 중차량을 승용차로 환산하는 척도이며, 이러한 승용차 환산 척도는 계량화가 가능하고 교통류특성을 반영할 수 있는 특성을 지녀야 한다. 본 연구에서는 PCE 산정의 척도로서 지체시간을 선정하였으며, 이의 계산을 위하여 도로구간을 추월가능구간과 추월금지구간으로 나누어 지체시간을 계산하였다. PCE의 환산은 Werner와 Morrall이 제시한 것처럼 Walker's Method를 이용하여 교통류 상호간에 발생하는 지체시간과 중차량 1대의 유입으로 인해 유발되는 지체시간을 비교하여 결정하였다. 또한 추월가능 및 금지구간 뿐만 아니라, 추월가능구간과 추월금지구간이 조합되어 연속적으로 나타나는 도로구간의 평균 PC료를 산정할 수 있는 방법을 제시하였다.

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도로교 최대차량하중효과 분석을 위한 모의해석기법 (Simulation Technique for Estimation of Extreme Traffic Load Effects on Bridges)

  • 황학주;김상효
    • 대한토목학회논문집
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    • 제13권4호
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    • pp.77-86
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    • 1993
  • 최근 들어 중차량의 과적화와 교통량 증가에 따른 교통정체현상의 발생은 세계적인 추세이며, 이에 의한 도로교의 손상은 심각한 상태이다. 도로교의 손상도나 안전수준은 도로교 설계활하중 및 차량하중에 의해 도로교에 발생하는 하중효과의 최대치의 특성과 밀접한 관계를 보이고 있다. 최대차량 하중효과는 단일 중차량에 의해서 발생하는 것보다는 상당한 중량을 가진 차량들이 동시에 제하되어 발생하는 경우가 많다. 따라서 본 연구에서는 도로교상에 발생하는 최대차량하중효과를 중요한 교통특성을 합리적으로 반영하여 분석할 수 있는 모의분석기법을 개발하였으며, 개발된 기법을 이용하여 교량형식 및 각종 차량하중특성과 통행특성(중차량 혼입률, 연행특성, 차중모형, 차간거리, 일일교통량 등)에 대한 최대하중효과의 민감도를 분석하였다.

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Fatigue property analysis of U rib-to-crossbeam connections under heavy traffic vehicle load considering in-plane shear stress

  • Yang, Haibo;Qian, Hongliang;Wang, Ping
    • Steel and Composite Structures
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    • 제38권3호
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    • pp.271-280
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    • 2021
  • In this study, the fatigue property of U rib-to-crossbeam connections in orthotropic steel bridge (OSB) crossbeams under heavy traffic vehicle load was investigated considering the effects of in-plane shear stress. The applicability of an improved structural stress (ISS) method was validated for the fatigue behavior analysis of nonwelded arc-shaped cutout regions in multiaxial stress states. Various types of fatigue testing specimens were compared for investigating the equivalent structural stress, fatigue crack initiation positions, and failure modes with the unified standards. Furthermore, the implications of OSB crossbeams and specified loading cases are discussed with respect to the improved method. The ISS method is proven to be applicable for analyzing the fatigue property of nonwelded arc-shaped cutout regions in OSB crossbeams. The used method is essential for gaining a reliable prediction of the most likely failure modes under a specific heavy traffic vehicle load. The evaluated results using the used method are proven to be accurate with a slighter standard deviation. We obtained the trend of equivalent structural stress in arc-shaped cutout regions and validated the crack initiation positions and propagation directions by comparing them with the fatigue testing results. The implications of crossbeam spans on fatigue property are less significant than the effects of crossbeams.

Characteristics of Heavy Metal Concentrations and Indoor Atmospheric Environments in Busan Metropolitan Area, Korea

  • Park, Jong-Kil;Kim, Yoo-Kuen;Lee, Hwa-Woon;Jang, Nan-Sim;Park, Moon-Ki
    • 한국환경과학회지
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    • 제11권8호
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    • pp.801-810
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    • 2002
  • The current paper describes the indoor/outdoor air quality in school environments through analyses of the heavy metal concentrations using Inductive Coupled Plasma(ICP). School environments in a heavy traffic area, two industrial areas, quasi-industrial area, and residential area were evaluated. The results were as follows: (1) The locations with the highest indoor and outdoor concentrations of heavy metals were the industrial areas followed by the heavy traffic area, residential area, and quasi-industrial area in a descending order of magnitude. Plus, the indoor heavy metal concentrations were higher then the outdoor ones. (2) The main heavy metal components were Zn, Al and Ca. Higher concentration levels were found indoors than outdoors. The heavy metal concentrations were also higher in the classrooms than in the corridor or outdoors. (3) The total heavy metal concentrations in the studied areas were highly dependent on the weather elements. including the relative humidity, mixing ratio, and wet-bulb depression. Accordingly, special ventilation systems are recommended to reduce air pollution in school environments.

Power Control Based Call Admission Control Method of the CDMA PCS System

  • 이강원;국광호;최정락
    • 경영과학
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    • 제16권1호
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    • pp.39-50
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    • 1999
  • This paper proposes a new call admission control method to enhance the reverse link capacity of a cell with heavy traffic in the CDMA PCS system under the uneven traffic load between cells. Since the capacity of a cell in the CDMA system is restricted by the total interference caused by terminals in the own cell and the adjacent cells, we can enhance the capacity of a cell by reducing the interference from other cells if possible. Our power control method allows that the signal powers received in base stations with heavy traffic be larger than those received in base stations with light traffic in order to make the interference due to other cells in the cells with heavy traffic relatively small. In the previous study, it was assumed that the signal power received by each base station in the CDMA PCS system is same when the call admission control algorithm is implemented. We could show that the reverse link capacity of a cell in the CDMA PCS system can be increased about 20% under our call admission control method.

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브로드캐스팅 트래픽을 최소화한 DHCP의 설계 및 구현 (Design and Implementation of DHCP with Minimized Broadcasting Traffic)

  • 안성진;정진욱;이상훈
    • 한국정보처리학회논문지
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    • 제3권4호
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    • pp.709-719
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    • 1996
  • DHCP는 호스트에게 IP(Internet Protocol) 주소나 구성 파라미터 (Configuration Parameter) 등을 동적으로 할당해주는 프로토콜이다. 그러나 이프로토콜은 메시지를 교환하기 위해 브로드캐스팅을 이용하기 때문에 네트워크에 과중한 트래픽의 발생 요인이 된다. 이러한 오버헤드를 줄이기 위해 메시지 교환시에 가능하면 브로드 캐스 팅을 피하고, 간결하고 효율적인 클라이언트-서버의 동작 메처니즘을 설계하였다. 본 연구에서는 DHCP가 유발하는 브로드캐스팅 트래픽 특성을 고찰하여 메시지를 유치캐스트 할 수 있는 방안과 트래픽을 줄일 수 있도록 알고리즘을 개선한 DHCP의 모델을 구현하였다.

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