• Title/Summary/Keyword: Transportation problems

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A study on Restructuring the Street Network for the Improvement of Traffic Problems in Metropolitan Central Area (대도시 도심교통문제의 개선을 위한 가로망체계의 개편방안에 관한 연구)

  • 임강원;임강원
    • Journal of Korean Society of Transportation
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    • v.5 no.2
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    • pp.81-95
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    • 1987
  • In line with the continued growth of car ownership, the traffic problems in central area of metropoles such as Seoul would become increasingly degraded. comparing with most western cities, the problems in Seoul are characterized by the improportionately high rates of intersection delay, station congestion, traffic accidents caused by weaving conflicts and pedestrian congestion. It is caused by the lack of flexibility I street network, which is prerequisite for upholding the efficacy of traffic management and control, resulted from the simplicity of network graph in terms of connectivity, street density and distribution by width. This pattern has been resulted from the prolonged policy pursuing the street-widening of the nagging bottleneck in such a short period since the 1950s, comparing that most western cities had undergone over several centuries an age of horse-and-vehicle transportation. In order to improve the expected traffic problems in central area over the coming periods of motorization, it is imperative to restructure the street network in Central Seoul so that the efficacy of traffic management and control may be operative. Based upon the long-range planning the street network should be restructured by stages so that cenral traffic may be controled by one-way operation and most through-traffic be detoured around fringe area.

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Extended Hub-and-spoke Transportation Network Design using a Symbiotic Evolutionary Algorithm (공생 진화알고리듬을 이용한 확장된 hub-and-spoke 수송네트워크 설계)

  • Shin Kyoung-Seok;Kim Yeo-Keun
    • Journal of the Korean Operations Research and Management Science Society
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    • v.31 no.2
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    • pp.141-155
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    • 2006
  • In this paper, we address an extended hub-and-spoke transportation network design problem (EHSNP). In the existing hub location problems, the location and number of spokes, and shipments on spokes are given as input data. These may, however, be viewed as the variables according to the areas which they cover. Also, the vehicle routing in each spoke needs to be considered to estimate the network cost more correctly. The EHSNP is a problem of finding the location of hubs and spokes, and pickup/delivery routes from each spoke, while minimizing the total related transportation cost in the network. The EHSNP is an integrated problem that consists of several interrelated sub-problems. To solve EHSNP, we present an approach based on a symbiotic evolutionary algorithm (symbiotic EA), which are known as an efficient tool to solve complex integrated optimization problems. First, we propose a framework of symbiotic EA for EHSNP and its genetic elements suitable for each sub-problem. To analyze the proposed algorithm, the extensive experiments are performed with various test-bed problems. The results show that the proposed algorithm is promising in solving the EHSNP.

Optimal Poultry Litter Management through GIS-based Transportation Analysis System

  • Kang, M.S.;Srivastava, P.;Fulton, J.P.;Tyson, T.;Owsley, W.F.;Yoo, K.H.
    • Journal of The Korean Society of Agricultural Engineers
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    • v.48 no.7
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    • pp.73-86
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    • 2006
  • Concentrated poultry production in the State of Alabama, U.S.A. results in excessive poultry litter. Application of poultry litter to pastures and row crops serves as a cheap alternative to commercial fertilizer. However, over the years, poultry litter application to perennial forage crops in the Appalachian Plateau region of North Alabama has resulted in phosphorus (P) buildup in soils. Phosphorus index (P-index) and comprehensive nutrient management plans (CNMP) are often used as a best management practice (BMP) for proper land application of litter. Because nutrient management planning is often not done for small animal feeding operations (AFOs), and also because, in case of excess litter, litter transportation infrastructure has not been developed, over application of poultry litter to near by area is a common practice. To alleviate this problem, optimal poultry litter management and transportation infrastructure needs to be developed. This paper presents a methodology to optimize poultry litter application and transportation through efficient nutrient management planning and transportation network analysis. The goal was accomplished through implementation of three important modules, a P-Index module, a CNMP module, and a transportation network analysis module within ArcGIS, a Geographic Information System (GIS). The CNMP and P-Index modules assist with land application of poultry litter at a rate that is protective of water quality, while the transportation network analysis module helps transport excess litter to areas requiring litter in the Appalachian Plateau and Black Belt (a nutrient-deficient area) regions. Once fully developed and implemented, such a system will help alleviate water quality problems in the Appalachian Plateau region and poor soil fertility problems in the Black Belt region by optimizing land application and transportation. The utility of the methodology is illustrated through a hypothetical case study.

Estimation of Transportation Infrastructure Scale for Evaluation of Super-Tall Building Locational Appropriateness: Focusing on Urban Area (초고층건축물 입지적정성평가를 위한 교통기반시설의 규모산정방법에 관한 연구: 도심지역을 기준으로)

  • Kim, Hyun Ju;Oh, Young Tae;Nam, Baek
    • Journal of Korean Society of Transportation
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    • v.31 no.1
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    • pp.15-24
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    • 2013
  • To accommodate urban concentration of population, multi-purpose super-tall buildings have been introduced, but they induce many travel demands causing regional traffic problems. While several travel demand management policies such as transit promotion or parking limits are presented to alleviate such problems, transportation infrastructure are still insufficient to meet high demands. In this study, super-tall buildings are categorized by scale and purpose, then mode-specific derived demand is estimated using modal share of each category. Optimal transportation infrastructure level is determined by condition-based average changing amount yielded by street network delay (in case of road) or the number of transit routes (in case of transit).

Network Enlarging Search Technique (NEST) for the Crew Scheduling Problem

  • Paek, Gwan-Ho
    • Journal of the Korean Operations Research and Management Science Society
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    • v.19 no.2
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    • pp.177-198
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    • 1994
  • We consider an algorithm for the Crew Scheduling Problem (CSP) based on the Transportation Problem approach. The main flows of the algorithm are arranged in three steps. First we propose a heuristic algorithm of the greedy principle to obtain an initial feasible solution. Secondary we present a method of formulating CSP into a Modified Transportation Problem format. Lastly the procedures of network search to get the optimal solution are presented. This algorithm can be applied to the general GSP and also to most combinatorial problems like the Vehicle Routing Problems. The computational results show that the large size CSP's could be tackled.

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A Survey on the Real Time Vehicle Routing Problems (실시간 차량 경로 계획 문제의 연구 동향)

  • Yang, Byoung-Hak
    • Journal of the Korea Safety Management & Science
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    • v.10 no.1
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    • pp.155-166
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    • 2008
  • During last two decades the transportation system has developed into very intelligent system with GIS, GPS and ITS. The practical transportation management system provides real time response module to manage the customer's order. We have surveyed research papers on the real time vehicle routing problem in last two decades to figure out the dynamic vehicle routing problem. The papers are classified by basic routing algorithms and by managing the dynamic events which are the order management, the routing re-optimization, the routing post-optimization and the waiting strategy.

Challenges of Transport Sector in India: A Dyadic Perspective

  • Potluri, Rajasekhara Mouly;Tejaswi, Satagopam Padma
    • The Journal of Asian Finance, Economics and Business
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    • v.5 no.3
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    • pp.95-102
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    • 2018
  • The objective of this research is to explore the diverse challenges faced by the customer as well transport providers through the selected modes of transportation of the second most populous country in the world - India. Two separate well-structured questionnaires administered to garner the opinions on different challenges. A random sample of 100 equally selected from the customers of 3 modes of transportation along with 30 transport providers. The collected data was analyzed in Microsoft Excel and R Studio platforms using Percentile Rank Tool and R Programming Language for Chi-square test respectively. Traffic congestion coupled with parking is the major problem in case of roadways while Safety and cleanliness in railways are the first amongst the problems to reckon with. High fares and lack of trained employees are the biggest challenges faced by aviation industry. The research is concentrated only in the states of Andhra Pradesh and Telangana in India with most widely used three modes of transportation viz., Road, Rail and Airways. This research paper is first of its kind which has collected the opinions of both customers as well transport providers on the problems faced. This research proffers information about the challenges faced by the customers which there will be an enormous possibility to review their strategies and plans.

A Study on the Effects of Reusable Packaging Materials through Module-Type Product Transportation on Logistics Costs (모듈형 제품수송을 통한 재사용 포장재 사용이 물류비용에 미치는 영향에 관한 연구)

  • Kim, Byeong Chan;Yang, Dae Yong
    • Journal of Korea Society of Digital Industry and Information Management
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    • v.10 no.3
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    • pp.261-272
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    • 2014
  • Home appliances go through a couple of packaging stages from the plant to consumers. The primary packaging, inner packaging for each part, happens for protection after products leave the plant. The secondary packaging happens in the unit of product, ensuring cushioning packaging to protect products from movement. The final tertiary packaging is for transportation and delivery. Each stage of product packaging, however, costs a lot of money because of disposable packaging materials used in each stage including vinyl, tapes, Styrofoam, and corrugated cardboards. Discarded packaging materials also cause environmental problems. In an effort to come up with a measure to solve those problems, this study proposed a plan to minimize logistics costs with semi-permanent packaging materials to replace disposable ones including Styrofoam, vinyl, and corrugated cardboards in the stages of inner packaging, cushioning packaging, product unit-based packaging, and transportation. The study also developed a model to cut down logistics costs by reducing various packaging stages including the primary, secondary, and tertiary stage only to the secondary one through module-type products instead of the transportation- and delivery-type ones, as well as demonstrated the excellence of the study through numerical analysis.

A Study on the Categorization System and Performance Parameters for the development of the Tube Transportation System's Requirements (튜브운송시스템 요구사항 개발을 위한 분류체계 및 성능변수 추출에 관한 연구)

  • Choi, Yo Chul;Kwon, Huck Bin
    • Journal of the Korean Society of Systems Engineering
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    • v.5 no.2
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    • pp.17-26
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    • 2009
  • This paper is about that case study of the Tube Transportation System that the new transportation system offering passenger and logistic service in a metropolis having plenty of the floating population or between medium-sized cities, and solving large issues like terrible traffic jams and environmental problems etc. in this region. Also it presented that elicitation results of performance parameter and the categorization system of it applying a systematic analysis methodology. By the medium of this paper, It showed that definition, case study, performance parameters, and the categorization system of parameters of a general tube transportation system before developing requirements of a specific tube transportation system. From now on, it will come in pretty handy in systems engineering of activities to establish a concept of a new tube transportation systems and develop requirements.

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A Genetic Algorithm for Route Guidance System in Intermodal Transportation Networks with Time - Schedule Constraints (서비스시간 제한이 있는 복합교통망에서의 경로안내 시스템을 위한 유전자 알고리듬)

  • Chang, In-Seong
    • Journal of Korean Institute of Industrial Engineers
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    • v.27 no.2
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    • pp.140-149
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    • 2001
  • The paper discusses the problem of finding the Origin-Destination(O-D) shortest paths in internodal transportation networks with time-schedule constraints. The shortest path problem on the internodal transportation network is concerned with finding a path with minimum distance, time, or cost from an origin to a destination using all possible transportation modalities. The time-schedule constraint requires that the departure time to travel from a transfer station to another node takes place only at one of pre-specified departure times. The scheduled departure times at the transfer station are the times when the passengers are allowed to leave the station to another node using the relative transportation modality. Therefore, the total time of a path in an internodal transportation network subject to time-schedule constraints includes traveling time and transfer waiting time. In this paper, a genetic algorithm (GA) approach is developed to deal with this problem. The effectiveness of the GA approach is evaluated using several test problems.

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