Vukan VuchicUniversity of Pennsylvania | UP · Department of Electrical and Systems Engineering
Vukan Vuchic
Dipl-Ing, Belgrade; MEng & Ph.D., Berkeley; Honoris causa CNAM-Paris, France & Waterloo, Canada
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January 1967 - June 2010
Publications
Publications (93)
According to the Belgrade Master Plan for 2021, the public transportation system for the city and its region will include three rail modes: a modernized existing tramway, regional rail, and a new light rail transit (LRT) mode. In the coming years all three rail modes should be developed simultaneously and in a coordinated manner. The introduction o...
Individual 45° [0011] tilt grain boundaries in Y{sub l}BaâCuâO{sub 7-x} thin films grown on biepitaxial substrates were studied. The thin films were grown using both pulsed organometallic beam epitaxy (POMBE) and laser ablation. Transport characteristics of the individual grain boundaries were measured including resistance -- temperature (R-T) and...
The mechanisms of the sputter-induced orientation change in YBaâCuâO{sub 7-x}(YBCO) films grown on MgO (001) substrates by pulsed organometallic beam epitaxy (POMBE) are investigated by x-ray diffraction. Rutherford backscatter spectroscopy (RBS), cross-section TEM (XTEM) and microanalysis. It is found that the W atom implantation concurring with t...
This chapter focuses on urban transportation. It is written by the moderator of the session on Land Transportation. He asked the five speakers to report on positive achievements and challenges in their cities or countries. The chapter starts with the moderator's review of developments and trends in urban transportation and a summary of the five rep...
The impacts of a changing transportation system on land consumption are analyzed. An analytical model with which to examine the intrinsic relationships between the volume of activities, the intensity of land use, and the modal split of generated trips is formulated on the basis of an idealized urban region that contains a city within radius R. The...
The 20(th) century witnessed revolutionary developments in transportation technology with major impacts on the form and character of cities. Progress in increasing mobility has brought many benefits as well as serious problems, particularly in deterioration of livability and sutstainability. Increase in auto ownership led to serious problems of chr...
The 20(th) century witnessed revolutionary developments in transportation technology with major impacts on the form and character of cities. Progress in increasing mobility has brought many benefits as well as serious problems, particularly in deterioration of livability and sustainability. Increase in auto ownership led to serious problems of chro...
The University of Pennsylvania is located in Philadelphia, Pennsylvania. Activities within the campus are supported by a host of transportation modes: private automobile, commercial vehicles, public transportation (including bus, light rail, heavy rail, and commuter rail), bicycling, and walking. In an effort to enhance the overall functioning of t...
The University of Pennsylvania is located in Philadelphia, Pennsylvania. Activities within the campus are supported by a host of transportation modes: private automobile, commercial vehicles, public transportation (including bus, light rail, heavy rail, and commuter rail), bicycling, and walking. In an effort to enhance the overall functioning of t...
A brief review of the Light Rail Transit (LRT) and Bus Rapid Transit (BRT) modes, based on facts and experiences, is presented. The concept of LRT developed from the modernization of the traditional tramways, including the features of upgrading of street operations to separate ways, construction of tunnels on short sections in city centers, and int...
The only modern text to cover all aspects of urban transit operations, planning, and economics
Global in scope, up-to-date with current practice, and written by an internationally renowned expert, Urban Transit: Operations, Planning, and Economics is a unique volume covering the full range of issues involved in the operation, planning, and financin...
This paper shows the iterative approach to solving transit network design problem, particularly with variable transit demand under a given fixed total demand. Although recent studies, which use a simplified combinatorial search approach, showed their capability of building optimal transit networks and handling the complicated transit travel time ch...
In industrialized countries, the process of urbanization has been largely completed, and the majority of population lives in urbanized areas. In developing countries, the same trend of population shift from rural to urban areas is still continuing. The resulting rapid growth of cities in recent decades has created problems of providing utilities an...
Pursuing a low-cost, yet modern, high-quality, medium-capacity transit system to improve their transit services, several Korean cities have opted for automated guided transit systems. Yet in 1999 the city of Jeonju decided to introduce a light rail transit (LRT) system not only to improve its transit services but also to improve living conditions,...
Do the transportation profession, its policy leaders, and its publications harbor a bias against transit - particularly against rail - and against balanced intermodalism, all of which are vital to livable cities? A distinguished researcher makes his diagnosis and offers a prescriptive remedy to ensure the profession's positive contribution to livab...
With little investment required for operating in streets, bus services are often designed to serve many overlapping routes with frequent stops. To upgrade services and attract choice riders, major bus routes should be provided with exclusive lanes, preferential signals, and fewer but more distinct stops. The Federal Transit Administration's (FTA) B...
High speed rail (HSR) systems have a proven record of efficient services in about a dozen countries. Recently, Magnetic Levitation (Maglev) technology for high speed ground transportation (HSGT) has been proposed for many intercity and regional lines in Germany, Japan, United States, and other countries. Maglev developers claim that their system ca...
In 1966, the United States Congress created the Washington Metropolitan Area Transit Authority (WMATA) to take control of the District's private bus system and develop a new Metro network for the Nation's capital. Following extensive planning, construction of Washington's Metrorail transit system started in 1969. Seven years later, revenue servi...
Selection of transit modes is one of the most important decisions in the transit planning process. A particularly important decision is the selection between bus and rail modes, because it influences the type of service that will be offered and, more importantly, the role transit will play in the city. Ultimately, such a decision has an impact on t...
This is a clear account of the application of electron-based microscopies to the study of high-Tc superconductors. Written by leading experts, this compilation provides a comprehensive review of scanning electron microscopy, transmission electron microscopy and scanning transmission electron microscopy, together with details of each technique and i...
Graphical scheduling is an old technique that has been neglected, or never acquired, in many NorthAmerican transit agencies. It retains its advantages in basic schedule design and analysis as it eases the solution to problems that are difficult to solve analytically. Even information about simple routes is enhanced by the detailed operating charact...
The twenty-first century finds civiliation heavily based in cities that have grown into large metropolitan areas. Many of these focal points of human activity face problems of economic inefficiency, environmental deterioration, and an unsatisfactory quality of life—problems that go far in determining whether a city is "livable." A large share of th...
At the closing of the second millennium our civilization can boast a remarkable progress in technological developments which have been growing at an exponential pace. Telecommunications, jumbo-jets and personal computers have become ubiquitous in many countries in recent decades. In the "softer" area of managing complex systems, and even more so in...
The sputter-induced epitaxy change of in-plane orientation occurring in YBa2Cu3O7-x (001) thin films grown on MgO (001) substrates by pulsed organo-metallic beam epitaxy (POMBE) is investigated by a series of film growth and characterization experiments, including RBS and TEM. The factors influencing the orientation change are systematically studie...
The free selection of travel between automobile and transit modes results in the individual equilibrium condition, which is not socially optimal. It is shown that shifting travel from cars to transit under most conditions results in travel improvements for both modes. To implement this win-win change, however, it is necessary to decrease the disuti...
There are a number of factors which contribute to the continuous pressure for driving in different cities. However most serious, but often overlooked is the problem that the structure of costs of driving stimulates excessive car use. This paper presents the structure of driving costs and classifies then into user, social and environmental costs. Th...
All developed countries experience similar trends and problems in urban transportation: growth of cities and affluence result in an increase in car dependency. Increased volumes of car travel lead to congestion and many negative effects, often termed as the "collision of cities and cars." A review of urban transportation policies and their implemen...
The concept of "Personal Rapid Transit," or PRT, was conceived nearly 30 years ago. It is supposed to have an extensive network of elevated guideways--light concrete or steel beams on columns--with stations every 2-3 blocks. Small, electrically powered vehicles, with 3-5 seats, would carry passengers automatically to any station in the network.
Tilt grain-boundary junctions with a 45 ° [001] misorientation were formed in YBa2Cu30 7 x (YBCO) thin films grown by pulsed organometallic beam epitaxy on (100) MgO substrates. The junctions were introduced at predetermined locations due to a modification of the orientation relation between the thin film and substrate following a low-energy argon...
A set of 45° [001] bi-epitaxial YB2Cu3O7−x thin film grain boundaries was studied to compare the effects of the microstructure on transport properties. The grain boundaries were made using two different deposition techniques: pulsed laser deposition (PLD) and pulsed organometallic beam epitaxy (POMBE). The transport properties were highly dependent...
It is well known that high-angle grain boundaries in YBa 2 Cu 3 O 7−x (YBCO) show weak-link effects and behave as Josephson junctions. This kind of grain boundary junction (GBJ) has potential applications in magnetic field measurement and electronic devices. This work studies the microstructure of artificially made GBJs in YBCO films on (001) MgO a...
When increasing use of the private automobile intensified street traffic congestion, cities, generally pursued one or two types of policies. The "Car accommodation policy" was aimed 'primarily at accommodating the car and highway traffic, neglecting all other modes. The "Balanced transportation policy" was directed to achievement of a co-ordinated...
MgO films and YBaâCuâO{sub 7-δ}/MgO multilayer films were developed with the pulsed organometallic beam epitaxy (POMBE) growth technique, and grain boundary junctions were fabricated from the films to demonstrate the utility of the multilayers. High-quality MgO films were grown on LaAlOâ substrates by POMBE using a Mg(dpm)â precursor. MgO crystall...
A versatile multilayer technique has been developed to form 45° YBa2Cu3O7−x [001] tilt grain boundary junctions on LaAlO3 substrates. An epitaxial MgO layer is initially deposited on a (100) LaAlO3substrate using pulsed organometallic beam epitaxy (POMBE). After a pregrowth sputter treatment, an YBa2Cu3O7−x thin film is then grown using POMBE. The...
The concept of time-area occupancy by vehicles captures in the same unit not only the quantity of ground area (or space) that is required for safe vehicle movement or for storage but the period of time for which the area is occupied as well. Another advantage of time-area measure is that it links the two usually different concepts of static and dyn...
The extensive planning and construction of high-occupancy vehicle (HOV) facilities during the past 20 years has resulted in more efficient freeway operations in many cities. There are, however, considerable differences among the effects of different types of HOV facilities, such as those converted from the existing lanes versus the newly constructe...
We have investigated the normal-state resistance and the excess low-frequency (1/{ital f}) noise in 45° tilt [001] grain-boundary junctions in YBaâCuâOâ thin films. A characteristic temperature dependence of the resistance fluctuations and a linear temperature dependence of the grain-boundary resistance (with a negative temperature coefficient) em...
Grain boundaries can act as weak links in the high T<sub>c</sub> materials. If properly controlled, these grain boundaries can be used in various device applications. We have been able to reproducibly form 45° [001] tilt grain boundary junctions in YBa<sub>2</sub>Cu<sub>3</sub>O<sub>7-x</sub> thin films. The films were grown-on MgO substrates using...
A low voltage argon ion sputter technique was used to form grain boundary junctions in YBa 2 Cu 3 O 7-x thin films on MgO. The YBa 2 Cu 3 O 7-x thin film grown on a pre‐sputtered region of MgO was rotated 45° about the [001] axis relative to the YBa 2 Cu 3 O 7-x thin film grown on an adjacent unsputtered region of the substrate. YBa 2 Cu 3 O 7-x th...
Most high angle grain boundaries in high-T _{c} superconductors exhibit weak link behavior. The Josephson-like properties of these grain boundaries can be used for many device applications such as superconducting quantum interference devices (SQUIDs). The structure-property relationship of different types of 45 ^circ (001) YBa_2 Cu_3O_{7-x} thin fi...
Grain boundaries can act as weak links in the high (Tc) materials. If properly controlled, these grain boundaries can be used in various device applications. We have been able to reproducibly form 45 deg (001) tilt grain boundary junctions in YBa2Cu3O(7-x) thin films. The films were grown on MgO substrates using a pre-growth substrate treatment. A...
There is a companion report about conversion to Metrorail rail system dated 1993.
SEPTA has made significant improvements on its Regional Rail System since its takeover from Conrail some 10 years ago. This system now offers highly reliable service; stations are clean, many have obtained improved platforms, signs and other equipment; Trailpasses are used extensively. Yet, the ridership is low relative to the excellent coverage th...
The main objectives of this study are to: Clearly define an upgraded bus transit system; Find out and evaluate present condition of bus services with respect to their upgrading from the simple service in mixed traffic in urban streets; Define the reasons why and under what conditions bus service improvements should be introduced; Define the obstacl...
Transportation has historically had a major influence on cities - their locations, growth and form. Civil engineers were the leading public servants in construction of railway and transit systems. With diversification of transportation and, particularly, growth of highways, the solutions to urban transportation have become extremely complex. Instea...
SEPTA's Regional Rail System has an extensive network of 7 diametrical lines. However, its ridership is only 90,000 per weekday, much lower than the riderships of the recently built regional metrorail systems, such as BART and WMATA. The project developed a plan to upgrade SEPTA's Regional System by construction of high platforms, purchasing new ro...
SEPTA Regional Rail was operated as an old fashioned commuter railroad. This report suggests how to modernize it to an all day multidirectional service.
The increasing importance of regional rail systems for growing cities and metropolitan areas has been shown more clearly in North America than anywhere else in the world. In spite of extremely auto-oriented developments and policies which do not favor railways, a number of North American cities have extended and improved their regional rail systems...
Passenger transfers among transit lines involve certain "resistance", because they cause some delay and require passenger orientation and walking between vehicles on different lines. Therefore it is sometimes believed that transfers are undesirable and that they should be avoided whenever possible. The fact is, however, that transit networks with m...
Most transit networks are designed empirically. For bus networks this process 1s often satisfactory because bus routes and networks are very dependent on local conditions, and they can be easily modified, allowing easy corrections of problems which line design may cause in operations. However, with transit systems which have extensive infrastructu...
The purpose of this project is to analyze present operations of the Green Lines in the subway and develop solutions to the operational problems, so that the great potential of the subway for high performance and an attractive level of service for passengers can be fully realized.
SEPTA Subway Surface Lines were evaluated for low cost improvements to their operations.
Urban Railways and the Civil Engineer, Institution of Civil Engineers Conference, Thomas Telford House Ltd., London, U.K., 1987—reviewed by Vukan R. Vuchic.
Parallel Processing for Supercomputers and Artificial Intelligence, edited by Kai Hwang and Douglas DeGroot, McGraw-Hill, New York, 1989—reviewed by Stavros A. Zenios.
This paper presents the results of research on metro (rapid transit) networks, focusing on their geometric characteristics. The object is to define the most important measures, indicators, and characteristics of geometric forms that can improve the present predominantly empirical methods used in metro network planning and analysis. Several measures...
Since its takeover of the Regional Rail System from Conrail in 1983, SEPTA has made numerous efforts to adjust its facilities and operations to the needs of a modern regional rail system. In order to meet the needs of a modern transit-type operations of regional rail with shorter headways and greater operational flexibility, the infrastructure, suc...
A definition is given of the different mass transport systems on the basis of the three characteristics: bed, technology and operation. An analysis is made in particular of the medium capacity transport systems by means of a comparative analysis between the light metropolitan railway (LRT) and the fully automated systems (AGT). From an analysis of...
Mr. Vukan R. Vuchic deals with the latest developments of metro networks and with their future state in the 21st century. He recalls the basic characteristics of metro and the positive and stimulating role it can play in large cities. While its first networks were opened more than a century ago, metro still knows an important growth: for example,...
The O-Bahn system, developed in the Federal Republic of Germany, consists of conventional diesel buses equipped with a special guidance mechanism that can be extended or retracted. The vehicles thus can run on regular streets or on special guideways that have two simple vertical guidance surfaces. The O-Bahn concept is intended to combine the advan...
Completion of the Center City Tunnel in Philadelphia in late 1984 connected two previously separate sets of lines (Western--formerly Pennsylvania and Northern--formerly Reading), combining them into an integrated regional rail system. The methodology, process, and major results of the planning for the regional rail systems are presented in this pap...
The purpose of this project has been to plan line pairings in the unified Regional High Speed Lines (RHSL) network when the Center City Tunnel is opened. While detailed schedules were not part of this project, headways and train consists have been determined for all lines for peak and off-peak periods.
Considerable portion of academic literature on urban transportation has been supportive of policies which resulted in extensive urban freeway construction, but highly critical of public investments in transit. This paper challenges these views and points out many flaws in their basic arguments. Criticism of rail transit is particularly emotionally...
This study analyzes the optimum number of stops and the optimal vehicle stopping policy for operation of a transit route. Two optimality objectives are considered: minimum user travel time and minimum total cost (user cost plus vehicle operating cost). Three types of vehicle stopping schemes are incorporated in the model: all-stop, on-call stopping...
With the increases in wages since the 1950s, labor costs have become the dominant portion of operating costs for transit agencies. Efforts to increase productivity of operating labor have been particularly successful on rail transit systems. For example, development of high-capacity articulated cars, provision of separated rights-of-way and intro...
This study analyzes various methods of providing transit services in low-density areas. These areas can be classified into two major categories. First, suburban areas of medium and large cities; and second, entire medium and small cities which have low population densities. One of these types of areas is found in most cities. The focus of this stud...
Increase of transit speeds is one of the most effective ways of increasing the attractiveness of transit for urban travel. While surface transit in particular suffers from low speed, the desirability of higher speeds is not limited to it. Rapid transit has adequate speed for short to medium-distance trips in urban areas. However, for longer. trips...
Important conceptual studies and successful, practical mode comparisons for several cities are pointed out. Serious deficiencies of studies using hypothetical situations and comparing modes through costs only are shown on a diagram used in these studies. Methodology for mode evaluation consisting of several steps is presented. Requirements of passe...
The transporting capacities of different transit modes are often discussed, but values quoted for different modes vary widely because of differing assumptions. This paper presents the basic theory of capacity and gives explanation of and insight to three aspects which must be carefully considered in capacity analysis: Way capacity and station cap...
4 reports that describe various aspects of design elements of passenger terminals and transit platforms to a multimodal regional transportation center were prepared for the 53rd annual meeting of the Highway Research Board. Following is a list of titles and authors: Design of Outlying Rapid Transit Station Areas. By Vukan R. Vuchic and Shinya Kikuc...
Utilizes 2 existing systems for a comprehensive comparative study of bus and rail technologies and their different types of operations. It performs the analysis on 2 actual systems and does not utilize any hypothetical assumptions; it includes more system characteristics.
Rail transit represents a family of modes ranging from light rail to regional rapid transit systems and it can be utilized in a number of different cities and types of applications. Many European cities of medium size employ very successfully light rail mode for gradual upgrading of transit service into partially or fully separated high speed, reli...
Inadequate organization of public transport services in urban areas, particularly in the large ones, is one of the major reasons for the unsatisfactory level of service and economic problems of the operating companies. Despite the current trend toward mergers of transit operators into large public agencies, the services in most cities remain fragme...
Inadequate organization of public transport services in urban areas, particularly in the large ones, is one of the major reasons for the unsatisfactory level of service and economic problems of the operating companies. Despite the current trend toward mergers of transit operators into large public agencies, the services in most cities remain fragme...
Two transportation systems, following the same alignment, serve an area from which population commutes to a central point. One system has a constant speed and can be taken at any point along the line; the other has a discrete movement and can be boarded at stations only. The study analyzes the optimal station locations of the latter system for whic...
Schedule disturbances in public transport operations have a tendency to intensify along the line and propagate to successive vehicles due to the uneven accumulation of passengers. This phenomenon, affecting efficiency and reliability of service, occurs frequently with surface services due to street congestion, as well as with rapid transit when It...
Several factors influencing the optimal interstation spacings for line-haul passenger transportation, for example, rapid transit or commuter railroads, are analyzed with respect to the objective of minimum total passenger travel time. The study concentrates on a case in which the population of an area commutes to one central point. The number and l...
Widening of traffic arterials at signalized intersections is often done with the intention of increasing vehicular capacity of the intersection. An analysis of the impact of increased pedestrian crossing time resulting from the widening (particularly on undivided arterials) on capacity is presented. It is shown that when signal cycle length is fixe...