• Title/Summary/Keyword: urban transportation

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교통관련 포장지역 비점오염원에서의 오염물질 유출원단위 산정 (Determination of Pollutant Unit Loads from Various Transportation Landuses)

  • 이소영;이은주;;김이형
    • 한국물환경학회지
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    • 제24권5호
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    • pp.543-549
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    • 2008
  • Human activities and land-use practices are intensely widening the urban areas. High impervious surface areas cover much of urban landscapes and are the primary pollutant sources which can lead to water quality and habitat degradation in its watershed. As the urban areas expand, transportation land-use such as parking lots, roads, service areas, toll-gates in highways and bridges also increase. These land-uses are significant in urban pollution due to high imperviousness rate and vehicular activities. To regulate the environmental impacts and to improve the water quality of rivers and lakes, the Ministry of Environment (MOE) in Korea developed the Total Pollution Load Management System (TPLMS) program. The main objective is to lead the watershed for a low impact development. On a local scale, some urban land surfaces can be emitting more pollution than others. Consequently, in urban areas, the unit loads are commonly employed to estimate total pollutant loadings emitted from various land-uses including residential, commercial, industrial, transportation, open lands such as parks and golf courses, and other developed land like parking areas as a result of development. In this research, unit pollutant loads derived specifically from transportation land-uses (i.e. branched out from urban areas) will be provided. Monitoring was conducted over 56 storm events at nine monitoring locations during three years. Results for the unit pollutant loads of transportation land-use are determined to be $399.5kg/km^2-day$ for TSS, $12.3kg/km^2-day$ for TN and $2.46kg/km^2-day$ for TP. The values are higher than those of urban areas in Korean MOE and US highways. These results can be used by MOE to separate the pollutant unit load of transportation landuses from urban areas.

On bending, buckling and vibration of graphene nanosheets based on the nonlocal theory

  • Liu, Jinjian;Chen, Ling;Xie, Feng;Fan, Xueliang;Li, Cheng
    • Smart Structures and Systems
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    • 제17권2호
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    • pp.257-274
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    • 2016
  • The nonlocal static bending, buckling, free and forced vibrations of graphene nanosheets are examined based on the Kirchhoff plate theory and Taylor expansion approach. The nonlocal nanoplate model incorporates the length scale parameter which can capture the small scale effect. The governing equations are derived using Hamilton's principle and the Navier-type solution is developed for simply-supported graphene nanosheets. The analytical results are proposed for deflection, natural frequency, amplitude of forced vibration and buckling load. Moreover, the effects of nonlocal parameter, half wave number and three-dimensional sizes on the static, dynamic and stability responses of the graphene nanosheets are discussed. Some illustrative examples are also addressed to verify the present model, methodology and solution. The results show that the new nanoplate model produces larger deflection, smaller circular frequencies, amplitude and buckling load compared with the classical model.

도시보행공간의 기능에 대한 이론적 고찰 (The Theoretical Study on the Functions of Urban Space for Pedestrians)

  • 이양재
    • 대한교통학회지
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    • 제5권1호
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    • pp.75-83
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    • 1987
  • The modernistic rationalism which thinks much of the mathematical rationality and economic efficiency is widely spread in Korea economic planning, urban planning, urban transportation planning, and the like. As a result the demands to humanity, amanity, and so on have been disregarded in the name of rationality in urban spatial organization, the typical examples, one of the pedestrian space. The pedestrian space which is passed over easily from the view point of the modernistic rationalism, is actually the space that should be reflected abundantly in urban space. The author emphasized a need of reconsideration on the position of pedestrian space in urban spatial planning process, and adopted the theoretical research on the functions and roles of pedestrian space. In consequence of this study the functions of pedestrian space are considered : the first, the function as a space for moving, the second, the function as a space for buffer. the third, the function as a space for intermediation. the fourth, the function as a space for urban daily life. the fifth, the function as new urban environment-making factor.

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도시 빅데이터를 활용한 스마트시티의 교통 예측 모델 - 환경 데이터와의 상관관계 기계 학습을 통한 예측 모델의 구축 및 검증 - (Big Data Based Urban Transportation Analysis for Smart Cities - Machine Learning Based Traffic Prediction by Using Urban Environment Data -)

  • 장선영;신동윤
    • 한국BIM학회 논문집
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    • 제8권3호
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    • pp.12-19
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    • 2018
  • The research aims to find implications of machine learning and urban big data as a way to construct the flexible transportation network system of smart city by responding the urban context changes. This research deals with a problem that existing a bus headway model is difficult to respond urban situations in real-time. Therefore, utilizing the urban big data and machine learning prototyping tool in weathers, traffics, and bus statues, this research presents a flexible headway model to predict bus delay and analyze the result. The prototyping model is composed by real-time data of buses. The data is gathered through public data portals and real time Application Program Interface (API) by the government. These data are fundamental resources to organize interval pattern models of bus operations as traffic environment factors (road speeds, station conditions, weathers, and bus information of operating in real-time). The prototyping model is implemented by the machine learning tool (RapidMiner Studio) and conducted several tests for bus delays prediction according to specific circumstances. As a result, possibilities of transportation system are discussed for promoting the urban efficiency and the citizens' convenience by responding to urban conditions.

Extraction of Some Transportation Reference Planning Indices using High-Resolution Remotely Sensed Imagery

  • Lee, Ki-Won
    • 대한원격탐사학회지
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    • 제18권5호
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    • pp.263-271
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    • 2002
  • Recently, spatial information technologies using remotely sensed imagery and functionality of GIS (Geographic Information Systems) have been widely utilized to various types of transportation-related applications. In this study, extraction programs of some practical indices, to be effectively used in transportation reference planning problem, were designed and implemented as prototyped extensions in GIS development environment: traffic flow estimation (TFL/TFB), urban rural index (URI), and accessibility index (AI). In TFL/TFB, user can obtain quantitative results on traffic flow estimation at link/block using high-resolution satellite imagery. Whereas, URI extension provides urban-rural characteristics related to road system, being considered one of important factors in transportation planning. Lastly, AI extension helps to obtain accessibility index between nodes of road segments and surrounding district areas touched or intersected with the road network system, and it also provides useful information for transportation planning problems. This approach is regarded as one of RS-T (Remote Sensing in Transportation), and it is expected to expand as new application of remotely sensed imagery.

부산지역 도시교통체계의 개선방안에 관한 연구 (Improvement on the Urban Transportation System in Pusan Area)

    • 한국항만학회지
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    • 제8권1호
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    • pp.3-15
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    • 1994
  • Most of Cities are suffering from the traffic congestion problem with the vehicles increased. Especially, the City of Pusan is experiencing the severest traffic congestion with the lower read capacity and the higher travel demand than any other cities in the country. Thus, the purpose of this study was to grasp the conditions, review the problems and finally suggest the improvements which we faced at this time for the construction of the Urban Transportation System considered in Pusan area. Based upon the results, it was concluded that firstly the Urban Transportation System(UTS) in Pusan area should be constructed by the Public Transportation System in the center of the Public Transit Modes(i.e., bus and subway), secondly the Para-transit Modes(i.e., Light Rail Transit, LRT) introduced, and thirdly the Transportation Demand Management(TDM) implemented with the expansion of the transportation facilities if possible.

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전통적인 4단계 교통수요 예측 모형을 활용한 교통망 분석 - 미얀마 만달레이시 중심으로 (Analysis Transportation Network Using Traditional Four-step Transportation Modeling : A Case Study of Mandalay City, Myanmar)

  • 윤병조;웃위린;이선민
    • 한국재난정보학회:학술대회논문집
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    • 한국재난정보학회 2023년 정기학술대회 논문집
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    • pp.259-260
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    • 2023
  • The rapid urbanization and modernization observed in countries like Myanmar have led to significant concerns regarding traffic congestion, especially in urban areas. This study focuses on the analysis and revitalization of urban transport in selected areas of Myanmar. The core of urban transportation planning lies in travel forecasting, which employs models to predict future traffic patterns and guide decisions related to road capacity, transit services, and land use policies. Travel demand modeling involves a series of mathematical models that simulate traveler behavior and decision-making within a transportation system, including highways, transit options, and policies. The paper offers an overview of the traditional four-step transportation modeling system, utilizing a simplified transport network in the context of Mandalay City, Myanmar.

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도시지역의 통근통행만족수준 결정요인에 관한 연구 (A Study on the Determinants of Satisfaction Degree of Work-trip in Metropolitan Areas)

  • 김재익
    • 대한교통학회지
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    • 제13권2호
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    • pp.5-18
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    • 1995
  • The aims of this study is to analyzed determinants of work-trip satisfaction degrees in six major metropolitan areas. and to derive urban policy implications. As is well -known, the main determinant of travel satisfaction degree is travel time. However, other factors such as travel mode, psychological factor, and priority in residential location choice are also significant ones. The findings imply that transportation problems are deeply related with housing problems in urban areas. This results provides an evidence of the nature of urban problems, i.e. inter-connectiveness among urban problems. Therefore, this study emphasizes that all urban problems should be treated with careful consideration of other related-urban problems.

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