• Title/Summary/Keyword: heavy traffic

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Interchange 주변토양의 중금속 농도 분포

  • 이주광;강혜진;강희만;이찬영
    • Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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    • 2002.04a
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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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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 (교통량 과밀 도로주변의 토양과 가로수, 대기중 Pb, Cu, Zn 중금속 농도와 그 상관성에 관한 연구)

  • 박기학
    • Journal of Environmental Health Sciences
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    • v.18 no.2
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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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Economic Loss Assessment caused by Heavy Snowfall - Using Traffic Demand Model and Inoperability I-O Model (대설의 경제적 피해 - 교통수요모형과 불능투입산출모형의 적용)

  • Moon, Seung-Woon;Kim, Euijune
    • Journal of Korea Planning Association
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    • v.53 no.6
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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.

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

  • 박종길;장난심
    • Journal of Environmental Science International
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    • v.6 no.5
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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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A Mathematical Model for Determination of PCE's Based on Delay for Two-Lane Two-Way Highway (양방향 2차로 도로의 지체시간 산정을 이용한 승용차환산계수 결정이론)

  • 이승준;최재성
    • Journal of Korean Society of Transportation
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    • v.17 no.2
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    • pp.149-162
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    • 1999
  • One of the most important steps of the design, capacity and operation analysis stapes in the two-lane two way highways is the effect of heavy vehicle to traffic flow quality. This heavy vehicle's effect on traffic flow can be represented as PCE, which is the number of passenger cars that are displaced by a single heavy vehicle of a particular type under prevailing roadway, traffic, and control conditions. In this paper, we focus on the heavy vehicles effect on volume, speed, delay, and the maneuver of freedom which are major MOE's in traffic operation analysis and PCE criterion which should be measurable, determinable and able to reflect the traffic flow characteristics. Therefore, the objective of the paper is to determine the PCE criterion and to develop a new PCE determination method. In this study, delay is adopted as PCE criterion and, for calculation of delay, the highway is divided into the passing zone and the no-passing zone. PCE is determined by comparing the delay due to total traffic flow interaction with the delay due to a single heavy vehicle, Also, this paper proposes a new method to determine the average PCE on the highway that has the passing zones and no-passing zones.

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

  • Hwang, Hak Joo;Kim, Sang Hyo
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.13 no.4
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    • pp.77-86
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    • 1993
  • Recently it is reported in many countries that highway bridges are seriously damaged due to increasing volume of overloaded heavy vehicles. The safety of bridges are highly related to the design load level and the characteristics of extreme load effect induced by traffic loads during its lifetime. The maximum structural load effect during lifetime may be produced by simultaneous loading of trucks with moderate weights on a bridge rather than by single loading of extremely heavy trucks. In this study, a simulation technique to estimate extreme load effect due to traffic loadings has been developed, in which important characteristics of traffic loadings, such as heavy vehicle proportion, traffic mode, vehicle weights, headway distribution. daily traffic volume, etc., should be properly considered. In addition. sensitivity analysis on those factors have been performed.

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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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    • v.38 no.3
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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
    • Journal of Environmental Science International
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    • v.11 no.8
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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
    • Korean Management Science Review
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    • v.16 no.1
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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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Design and Implementation of DHCP with Minimized Broadcasting Traffic (브로드캐스팅 트래픽을 최소화한 DHCP의 설계 및 구현)

  • An, Seong-Jin;Jeong, Jin-Uk;Lee, Sang-Hun
    • The Transactions of the Korea Information Processing Society
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    • v.3 no.4
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    • pp.709-719
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    • 1996
  • DHCP(Dynamic Host Configuration Protocol)is a protocol which dynamically allocates an IP address and/or host configuration parameters to a host. But because this protocol uses broadcasting for message exchange, it causes heavy traffic and overload on the network. By avoiding unnecessary broadcasting and using a simple and efficient implementation model, we can reduce such heavy traffic and overload. We have studied on characteristics of the broadcasting the traffic caused by DHCP, and implement the model which can reduce traffic by improving algorithm and unicasting messages.

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