Existing Transportation Network Research Articles

The evolution of a reliable transport network

This article shows how transport networks may evolve in the future, driven by new technologies and new customer requirements for cost, reliability, and traffic growth. It does not simply compare new technologies and architectures, but accepts that most operators are not starting with a green-field site. It therefore also addresses the operator's problems of introducing and integrating new technologies into existing transport networks and migrating services from one transport technology to another. This in turn drives different technologies to evolve to new levels of reliability over time. The article is written from the perspective of an established European network operator, and differences are brought out from the evolution of networks in North America.

Mon/Fayette Route 51 to Pittsburgh Transportation Project: A Success Story in Integrating Congestion Management System Analysis, Major Investment Study, and National Environmental Policy Act Processes

The 1991 Intermodal Surface Transportation Efficiency Act placed new emphasis on transportation planning. In response, FHWA and FTA issued Joint Statewide and Metropolitan Planning Regulations (23 C.F.R §450). These regulations call for two studies, the congestion management system (CMS) analysis and the major investment study (MIS), which must be completed to analyze the best use of the existing transportation network and to determine whether and what transportation investments are needed in a metropolitan area. The intent is to use these studies as input to the metropolitan planning organization’s long-range transportation plan. The Pennsylvania Turnpike Commission (PTC) and the Southwestern Pennsylvania Regional Planning Commission (SPRPC) cooperatively developed and implemented an effective approach to navigate the Mon/Fayette Route 51 to Pittsburgh transportation project through a collaborative process integrating the CMS analysis and MIS. This approach also met the requirements of the Pennsylvania Department of Transportation’s (PennDOT’s) Preliminary Alternatives Analysis, one in a series of studies required under PennDOT’s National Environmental Policy Act (NEPA) implementing guidelines. PTC’s goal to advance a preferred major investment alternative into the next phase of project development was accomplished when SPRPC endorsed the integrated CMS analysis/MIS and preliminary alternatives analysis report. Presented is a success story in the effort to integrate the metropolitan planning and NEPA processes at the project programming level. It is hoped that the planning and NEPA principles applied can serve as a model to advance other transportation projects.

Development of an Eurasian transportation network: Potential and possibilities

Eurasia is the place in which the political and social situations are changing rapidly. In particular, the recent changes in the Soviet Union, China and North Korea will bring about big changes in transportation network in Eurasia. The difficulties of the existing transportation network in this area are examined. Directions for developing transportation networks between Korea, China, Mongolia and Russia are suggested with a focus to the unified Korea. Access to the Middle East, India and Southeast Asia by rail would be possible by connecting the missing links, and its competitiveness could be increased. The establishment of direct air routes can also reduce air passenger-km and fuel consumption quite a lot.

An optical infrastructure for future telecommunications networks

For the transport of the increasing traffic volume caused by existing and new narrowband services and evolving broadband services, the enhancement of the existing public telecommunication transport network is necessary. For this purpose an optical network layer with cross-connect and add/drop functionalities will be added to the existing transport network. A comparative analysis of space, time, and optical frequency division multiplexing has shown that for the time being optical frequency multiplexing is best suited for the realization of that new network layer. This multiplexing scheme offers the greatest advantages such as very high bandwidth utilization in the fiber and simple and efficient cross-connecting of high bitrate streams. In the near future, technology will be mature enough for the realization of a demonstrator network based on optical frequency division multiplexing. The functionalities of the optical network are evaluated and the results clearly show that optical frequency conversion and regeneration should be provided by the optical network. The article also deals with the realization aspects (cross-connecting, supervision, and operation and maintenance) of an optical node. >

SOLVING A NONLINEAR BILEVEL PROGRAMMING MODEL OF THE EQUILIBRIUM NETWORK DESIGN PROBLEM FOR KOREA

ABSTRACT A network design problem solves for link improvements or additions to an existing transportation network provided that a certain objective function such as social welfare is maximised. In addition, an equilibrium network design problem specifically requires each link to have user equilibrium flows.In this paper, two equilibrium transportation network design problems are formulated in a nonlinear bilevel programming framework; one with a budget constraint and one without. A bilevel programming formulation allows explicit consideration of the interaction between the public sector which supplies transportation facilities and the private sector which uses the given facilities. This paper presents a descent‐type algorithm to solve an equilibrium network design problem formulated in the nonlinear bilevel programming model for Korea. Numerical analysis using network data for a simplified Korean highway system is reported.

ALASKAN NATURAL GAS: WHICH ROUTE TO MARKET?

In this study the recent problem of choosing a route for bringing Alaskan natural gas to the lower forty-eight states is used to illustrate a technique for examining the effects of adding new sections to an existing transport network. The method develops demand, supply, and pipeline-network submodels, which provide data input to a modified version of the out-of-kilter algorithm (MOKA). The results of applying MOKA to the Alaskan natural gas problem indicate that routes entering the Lower Forty-Eight through Montana or Minnesota would deliver a larger total supply and produce fewer deficits than routes leading to California.

Status of coal gasification

A survey was made of economic and environmental trade-offs, in terms of land disturbance from mining, and water consumption, to be considered in choosing the Wellman-Galusha, Koppers-Totzek, or Lurgi coal gasification processes. Performance maximization, in terms of process efficiency or water consumption, was found to be application specific and site specific. Relatively small energy requirements appear to be best met through application of the Wellman-Galusha system, if water is not scarce; large users may opt for the other systems. The Lurgi system is advantageous for electrical power generation because its pressure enhances the economics of combined cycle plants. If methanation becomes the dominant mode because of an existing transportation network, the Lurgi units profit from their somewhat higher efficiencies. However, Koppers-Totzek units require less water. Descriptions of process technologies, system efficiencies, and water consumption for each of the processes are presented.

Land use planning: An optimizing model

An optimizing model for comprehensive land use planning (OPTPLAN) is described. Multiple objectives and constraints on desired growth patterns are considered simultaneously in arriving at optimal acreages of ten land use types in several regions within a county or city. Objectives are (i) minimization of conflict between different land uses, (ii) minimization of travel distance of new trips to the existing transportation network, (iii) generation of a fiscally sound plan, and (iv) minimization of environmental impact. Constraints are on each type of land use based on population and employment projections, projected mix of residential dwelling units, local commercial and institutional land needed per thousand persons, location and extent of new industries, open space requirements per thousand population, and natural resource considerations. Application of the model to Du Page County, Illinois is shown.