bluuebunny/crossref_metadata_2025 huggingface dataset:
Injury Severity and Duration of Hospital Stay for Urban Road Accidents in Riyadh
Authors: Al-Ghamdi Ali S.
Published: April 2007

A sample of 1,831 victims of urban road accidents in Riyadh was analyzed. The analysis consisted of two parts. First, the injury severity of 1,006 subjects was measured by the abbreviated injury scale (AIS). More than half the subjects were scaled with severe injuries (AIS ≥ 3). Association analysis between injury severity and accident characteristics (e.g., accident time, type, and location) was performed. Second, duration of stay at the hospital was examined for cases of injury as well as deaths. The probability density functions of the length of these time periods for cases of injury and death were found to be satisfactorily described by the γ distribution and by exponential distribution, respectively.
Lie Factor in Traffic Safety: Comparison of Police and Hospital Reporting of Seat Belt and Alcohol Use in Hawaii
Authors: Kim Karl
Published: April 2007

A linked database composed of police crash reports and hospital records was used to compare seat belt and alcohol use. For these linked cases, the police reported a belt use rate of 88.1 percent; hospital records, however, indicated a use rate of 59.9 percent. Although police overreported the seat belt use rate, they underreported the alcohol involvement rate. Hospital records indicated alcohol involvement in 25.5 percent of the cases; police reporting captured only a fraction of the alcohol cases (8.4 percent of total cases). In addition to reporting the general patterns of inconsistency between police and hospital reporting across driver, vehicle, and crash characteristics, it was shown that there are significant problems associated with reporting of seat belt and alcohol use. The analysis is based on comprehensive information from Hawaii of about 369 drivers with linked crash and hospital records in 1990. Some recommendations for improving the quality and accuracy of reporting are provided.
Overview of Three Expert Systems for Crash Data Collection
Authors: Thielman Carol Y. , Griffith Michael S.
Published: April 2007

There is a demand by the highway safety community for better quality crash data to meet a wide variety of needs. The goal of the FHWA Crash Data Collection Expert System Program was to use expert systems technology to improve the accuracy and consistency of police-reported data. The program and the three expert systems developed and evaluated—seat belt use derivation; vehicle damage rating, including extent of deformation; and roadside barrier problem identification—are discussed here. In the program, police officers used pen-based computers that contain the expert systems to collect on-scene crash data. Embedded in the expert systems is data collection knowledge derived from experts in crash data collection and analysis. The expert systems use this knowledge to intelligently select the data to collect and assign values to elements. This knowledge is also included in on-line help screens that help the officer accurately identify the physical characteristics of the crash scene. The expert systems were evaluated during two field tests. The field test results indicate that the expert systems were well accepted by the officers, that the systems were validated by experts in the expert system domain areas, and that the officers collected data at an average of about 2 min per expert system.
Implementation of a Timed Transfer Network at Norfolk, Virginia
Authors: Jeff Becker A. , Spielberg Frank
Published: April 2007

The principles and practices of designing and implementing a multicenter-based timed transfer network at a medium-sized transit agency are discussed. Information is presented on route structure concepts, network design tools and considerations, the effect of the service structure on passenger transfers, and rider behavior. Notable differences from existing practices and assumptions are emphasized, especially relative to the commonly used central business district–focused radial network. Both operational and customer aspects are presented.
Regional Commuter Buses and Their Potential Applicability in Connecticut
Authors: Allen John G.
Published: April 2007

The regional commuter bus is a long-established service concept encompassing the fastest and most comfortable bus transit. There is no universally applicable definition of the regional commuter bus, but it combines the flexibility of the bus with the comfort of commuter rail. Most regional commuter buses operate in suburb-to-city service, although some routes accommodate reverse-commute and suburb-to-suburb travel. The regional commuter bus serves a wider variety of origins and destinations than does rail transit. Yet like commuter rail, the commuter bus caters to longer-distance metropolitan travel, and it usually attempts to offer a comfortable seat to all passengers. Because of its amenity orientation and its fast service, the regional commuter bus often competes with the car on a basis of choice. The advantages of the regional commuter bus make it an option for planners to consider in markets in which ordinary bus service might not be applicable. One potential market for the regional commuter bus is in Connecticut’s southwest corridor. The zone from Bridgeport to Stamford, with its many urban centers, employment centers, and affluent suburbs, may be a promising market for high-amenity service. Vans or small buses capable of operating within the geometric limits of the Merritt Parkway would allow transit to compete effectively with the automobile along the tier of suburbs inland from I-95 and the New Haven rail line.
Access to Intercity Public Transportation Services from Small Communities: Geospatial Analysis
Authors: Spear Bruce D. , Weil Raymond W.
Published: April 2007

The U.S. Department of Transportation currently is evaluating national transportation policy on the role the federal government should play to improve access to intercity public transportation services from smaller communities and rural areas. An important first step in this evaluation is to determine the size and location of underserved markets. This question is particularly well suited to the kind of spatial analysis that is possible through geographic information systems (GIS) technology. Presented are the results of a geospatial analysis to identify those places that do not have reasonable access to intercity public transportation services and the potential impact of that lack of access on the people living in those places. By using national level, geospatial databases of intercity public transportation access points and locations of places defined in the 1990 census, the analysis employed GIS to create buffers of specified distances around each access point to find those places located beyond the buffers. A total of 443 places with populations between 2,500 and 50,000 were found to lie beyond a reasonable access distance to any intercity public transportation service. Those places are located predominantly in the rural Midwest, Appalachia, and the Mississippi Delta and along the Texas-Oklahoma border.
Improving Paratransit Scheduling by Accounting for Dynamic and Stochastic Variations in Travel Time
Authors: Fu Liping
Published: April 2007

Travel times in an urban traffic environment often are subject to dynamic and stochastic variations due to random fluctuations in travel demands, frequent interruptions of traffic controls, and unpredictable occurrences of traffic incidents. Although these variations inevitably affect the real-life performance of a paratransit system, they have not been taken into account in the routing and scheduling process by most existing paratransit scheduling systems. The potential effects of these variations on the operational characteristics of a paratransit system such as vehicle productivity and schedule reliability are examined. A dial-a-ride routing and scheduling system capable of modeling dynamic and stochastic travel times was used in the analysis. A series of numerical experiments was performed on a practical problem from the city of Edmonton, Alberta, under hypothetical travel time variation patterns. It was found that both dynamic and stochastic variations in travel times had important effects on the quality of the schedules, and an appropriate consideration of these variations in the scheduling process could substantially improve the reliability and productivity of the schedules.
Bus Stop Design and Automated Guidance for Low-Floor Buses: Evaluation of Prototypes with Investigation of Human Factors
Authors: Dejeammes Maryvonne , Coffin Florent , Ladreyt Thierry , Dessaigne Marie-France , Fouet Valérie , Dolivet Claude , Zac René
Published: April 2007

Low-floor vehicle design improves the accessibility of urban buses to people with reduced mobility. In France, on the basis of the experience gained from low-floor tramways, a system approach soon appeared necessary and the low-floor bus within the urban environment was considered. Described are the results of the research and development project initiated by the Grenoble network to reach efficient guidance solutions that would ensure minimal gaps at bus stops. Operating conditions of accessibility equipment on the vehicle (kneeling, access ramp) as well as driver capability to dock at the bus stop have been investigated. From the results, an improved bus stop was designed and two prototype systems—GIBUS visual aid and VISÉE guidance system—were conceived and tested. Evaluation of these during operation on a bus route in the city of Grenoble concentrated on assessing system performance and human factors so that recommendations could be drawn before implementation.
Evaluation Results of San Francisco Bay Area Station-Car Demonstration
Authors: Nerenberg Victoria , Bernard Martin , Collins Nancy E.
Published: April 2007

Presented is a summary of the evaluation of the first 2.5 years (November 1995–March 1998) of the San Francisco Bay Area Station-Car Demonstration. The 40 station cars were small battery-powered electric cars used for access to and egress from the Bay Area Rapid Transit District stations and for other local trips. The demonstration was a preliminary test of a larger vision for solving several problems associated with line-haul mass transit. Its purpose was to determine the viability of electric vehicles for short, everyday trips in a variety of settings: between home and a station; between a station and a work site; and as pool cars used at work sites. Other short trips were encouraged during the workday or during evenings and weekends when the cars were at participants’ homes. The participants and their opinions of the concept before entering and during the demonstration are described. Modal shifts, air emission benefits, energy impact, and many nonquantifiable effects are presented. A “10,000 station car” scenario based on data from the demonstration is presented to show the impact of a larger station-car deployment. Many of the lessons learned from the experiment are presented with the overall conclusions.
Who Noticed, Who Cares? Passenger Reactions to Transit Safety Measures
Authors: Wallace Richard R. , Rodriguez Daniel A. , White Christopher , Levine Jonathan
Published: April 2007

Safety and security are important considerations for the transit operator, but few empirical studies exist that measure the effectiveness of measures taken to improve transit safety either on actual crime (or other incident) data or transit passengers’ perceived safety. The current study focuses on the links between transit safety measures implemented in the Ann Arbor, Michigan, area; the visibility of these improvements to transit passengers; and perceived levels of safety. The findings indicate that the characteristics of passengers’ riding patterns, and whether a safety measure was noticed, all played some role in determining perceived safety. Additionally, ridership patterns and personal characteristics also affected whether passengers noticed safety enhancements. Of the measures undertaken, increased police presence and increased lighting proved most effective in increasing perceived levels of safety, and these also were the most visible. Safety measures also had their largest positive effect on perceptions in association with those transit places and situations perceived as least safe. In a similar vein, although women felt less safe overall than did men, they were more likely to notice safety enhancements and to feel safer as a result. Future efforts to build on this research should incorporate actual crime statistics, thereby extending the models discussed and providing a comprehensive view of the relationships among crime, safety enhancements, and passenger perceptions.
Heuristic Method for Optimal Diversion Control in Freeway Corridors
Authors: Wu Jifeng , Chang Gang-Len
Published: April 2007

An integrated control model and a heuristic algorithm for optimal diversion control in commuting corridors are presented. The proposed optimal control integrates ramp metering, intersection signal timing, and off-ramp diversion in an on-line environment that can minimize the total travel time of time-varying demand in nonrecurrent congestion. To reliably capture the flow interactions during freeway incidents, the proposed control model embodies the following three unique features: ( a) modeling traffic state evolution on surface streets with flow conservation within sections, flow transition between sections, and flow discharge at downstream intersections; ( b) estimating time-dependent model parameters adaptively with real-time traffic measurements, instead of assuming they are predetermined, as in most studies; and ( c) having an efficient solution algorithm. Preliminary numerical tests have demonstrated that both the proposed model and algorithm have the potential for use in on-line diversion control in commuting traffic corridors.
Dynamic Capacitated User-Optimal Route Choice Problem
Authors: Chen Huey-Kuo , Wang Chung-Yung
Published: April 2007

Link capacity side constraints are explicitly incorporated into the variational inequality-based dynamic user-optimal route choice problem. The corresponding dynamic capacitated user-optimal conditions for each origin-destination pair and time interval state that the generalized route travel times (composed of route travel times and queuing delays) experienced by travelers are equal and minimal. An augmented Lagrangian dual method that embeds the gradient projection algorithm is then proposed and validated with a numerical example. The computational performance of the gradient projection algorithm is also compared with the disaggregate simplicial decomposition algorithm in a preliminary attempt.
Time-Dependent Model for Departure Time and Route Choices in Networks with Queues
Authors: Lam William H. K. , Zhang Yanping , Yin Yafeng
Published: April 2007

A multiperiod time-dependent model for departure time and route choices in networks with residual queues is presented. The proposed model is meant to be used for strategic transportation planning, taking into account the effects of time-dependent queues that are carried over to the next period. The departure time choice is based on an incremental logit model, whereas the route choice follows an extended user equilibrium (UE) principle. This model is formulated as the variational inequality (VI) problem, which accounts for the major features of networks with residual queues, including the effects of queue delay and traffic flow truncation due to road exit capacity. The Jacobi method is used to solve the VI problem. In the proposed solution method, the diagonalization subproblem is equivalent to the steady state extended UE assignment for networks with queues. A simple numerical example is used to illustrate the application of the solution method.
Linear Programming Formulations for System Optimum Dynamic Traffic Assignment with Arrival Time-Based and Departure Time-Based Demands
Authors: Li Yue , Ziliaskopoulos Athanasios K. , Waller S. Travis
Published: April 2007

The system optimum dynamic traffic assignment problem, in which drivers fix their arrival rather than their departure times, is examined. A model is formulated as a linear program that simultaneously optimizes departure time and route choice. The model applies to multiorigin/multidestination problems, and the first-in-first-out condition is generally observed on the links and nodes of the network. An extension is discussed that accounts for combined departure time– and arrival time–based demand on the same network. The models are tested on an example network, and the results are discussed.
Network Equilibrium Model of Employment Location and Travel Choices
Authors: Chu You-Lian
Published: April 2007

A network equilibrium model for the simultaneous prediction of employment location, trip distribution, mode choice, and trip assignment is developed. The employment location choice was given by a simplified form of Putman’s employment allocation model. The trip distribution and mode choice were formulated as a nested logit model. Trip assignment was based on Wardrop’s “user-optimized” principle. The proposed combined employment location, trip distribution, mode choice, and assignment model can itself be reformulated as an equivalent minimization problem (EMP) so that the equilibrium conditions on the network and the location and travel demand functions can be derived as the Kuhn-Tucker conditions of the EMP. Under mild assumptions on the demand and link cost functions, the EMP is a convex programming problem with linear constraints, a great advantage from the computational aspect. In addition, a unique solution of the EMP exists that is equivalent to the proposed combined model. When applying the Evans algorithm to the equilibrium problem, the model is expected to be usable in a realistic application at a reasonable cost and within a reasonable time period. Several areas for further extensions of the model are also discussed.
Generalized Singular Value Decomposition Approach for Consistent On-Line Dynamic Traffic Assignment
Authors: Peeta Srinivas , Bulusu Srinivas
Published: April 2007

A framework for ensuring operational consistency of on-line dynamic traffic assignment in networks with advanced traffic management and information systems is proposed and investigated. Formulated within a stage-based rolling horizon framework, the model first solves a deterministic dynamic traffic assignment problem to predict the traffic network state for the near future while optimizing certain controller and user objectives and later seeks consistency between the predicted system state and the actual conditions unfolding on line. This approach ensures that future state predictions and path assignments are consistent with the current actual system state rather than the previously predicted (presumed) system state. The consistency problem is formulated as a constrained least-squares model. It is underdetermined, rank deficient, and potentially ill conditioned for general networks. In addition, it lacks well-behaved properties and has a fixed-point element, characteristics inherited from the dynamic traffic assignment problem. It is solved using orthogonal transformations based on generalized singular value decomposition (GSVD). Simulation experiments are conducted to analyze the effectiveness of the GSVD-based solution algorithm vis-à-vis ensuring consistency. The experiments emphasize the reliability and stability of GSVD in addressing the on-line consistency problem.
Solving Bilevel Network Design Problem Using a Linear Reaction Function Without Nondegeneracy Assumption
Authors: Cho Hsun-Jung , Lo Shih-Ching
Published: April 2007

A sensitivity analysis–based heuristic is proposed for application to solving the continuous equilibrium network design problem. The heuristic uses a minimum distance approach to generate sensitivity information and release the nondegeneracy assumption. The trip maker’s behavior is then represented by a linear approximation of the reaction function that is generated from the sensitivity information. Two numerical examples are given.
On-Line Algorithms for Truck Fleet Assignment and Scheduling Under Real-Time Information
Authors: Yang Jian , Jaillet Patrick , Mahmassani Hani S.
Published: April 2007

With greater availability of real-time information systems, algorithms are needed to support commercial fleet operators in their decisions to assign vehicles and drivers to loads in a dynamic environment. A rolling horizon framework for the dynamic assignment and sequencing of trucks to jobs consisting of picking up and delivering full truckloads when requests for service arise on a continuous basis is presented. A mathematical formulation of the problem faced at each stage is presented; its solution allows for the dynamic reassignment of trucks to loads, including diversion to a new load of a truck already en route to pick up another load, as well as for the dynamic resequencing of the order in which loads are to be served as new loads arrive and conditions unfold. Loads have associated time windows for pickup and delivery, and the objective function includes an explicit penalty cost for not serving a particular load. A solution algorithm is presented and implemented, and computational results are presented, yielding insight into various operational trade-offs in dynamic fleet operations. Because applicability of the solution algorithm is limited to relatively small problems, and given the stochastic dynamic nature of these systems, numerical experiments are performed to compare the quality of the solution obtained using this approach with the performance of simpler and less computationally demanding local rules.
Comparison of Link-Based Versus Route-Based Algorithms in the Dynamic User-Optimal Route Choice Problem
Authors: Chen Huey-Kuo , Chang Chia-Wei , Chang Mei-Shiang
Published: April 2007

One link-based algorithm (Frank-Wolfe) and three route-route based algorithms are compared for use in the dynamic user-optimal route choice problem. Computational experience with five test networks indicates that the route-based algorithms are in general superior to the link-based algorithm in terms of execution time but slightly inferior in terms of memory requirement.
Proposed Guidelines for the Prevention of Alkali-Silica Reaction in New Concrete Structures
Authors: Fournier Benoit , Bérubé Marc-André , Rogers Chris A.
Published: April 2007

The approach now under consideration by the Canadian Standards Association’s Technical Group on Alkali-Aggregate Reactions (AARs) to prevent the risk of deterioration associated with the use of potentially reactive aggregates in concrete is described. This approach involves a risk-evaluation process based on three factors judged critical for the development of damage in concrete structures due to alkali-silica reaction. The factors are ( a) the degree of reactivity of the particular reactive aggregate, ( b) the size of the concrete element and the environmental conditions it will face, and ( c) the expected service life of the structure. The proposed preventive action against AARs will depend on the actual risk level thus determined. The action will involve one or a combination of the following approaches: ( a) limit the alkali content in the concrete to a selected level, or ( b) use an effective supplementary cementing material (SCM) (or an effective combination of SCMs) in sufficient amounts.
Mitigation of Alkali-Silica Reaction in Pavement Patch Concrete That Incorporates Highly Reactive Fine Aggregate
Authors: Carpenter Andrea J. , Cramer Steven M.
Published: April 2007

The use of low-level replacements of mineral admixtures in reducing expansion of mortar bars due to alkali-silica reaction (ASR) was investigated. Silica fume, powdered bottle glass, fly ash, and slag cement were examined for their potential to mitigate ASR in portland cement concrete that incorporates reactive-waste glass aggregate. All the mineral admixtures under investigation decreased ASR expansion. However, only a few were able to bring expansions below the 0.20 percent limit of deleterious expansion specified by ASTM C1260. The cement replacement levels effective in reducing expansions below 0.20 percent were 20 percent for silica fume, 20 percent for specific fly ashes, and 40 percent for powdered glass. The only characteristic of the fly ashes identified for reducing ASR expansion was fineness, expressed as the percent retained in the No. 325 sieve. The mix incorporating 20 percent silica fume was found to be the most satisfactory for a planned pavement patch application. However, a second-choice mix that uses 40 percent powdered glass showed excellent potential for resisting ASR but achieved only 90 percent of the strength required in 24 hours.
Impact of Processed Cellulose Fibers on Portland Cement Concrete Properties
Authors: Buch Neeraj , Rehman Owais M. , Hiller Jacob E.
Published: April 2007

Processed cellulose fibers provide a desirable balance between mechanical, physical, and durability characteristics when placed in a cement matrix. The effect of processed cellulose fibers (natural) on the mechanical properties and dimensional stability properties of portland cement concrete and its subsequent use in the paving industry are studied. The mechanical and durability properties of three concrete mixtures [the standard Department of Transportation (DOT) mixtures for pavement construction and full-depth patch repair] with and without processed cellulose fibers were studied. The test results are very promising. There is a 10 percent improvement in compressive strength and a 40 percent improvement in impact strength of cellulose fiber concrete when compared with plain cement concrete mixtures. The average cellulose fiber concrete’s flexural strength after 24 hours was 3 MPa and the average 28-day flexural strength was 5 MPa. The inclusion of fibers shows a marginal improvement in fracture toughness of the concrete. Inspecting the abrasion and F-T data illustrates the beneficial effects of fibers in plain concrete. The mechanical properties of the two field mixtures are similar at early ages. However, the modified fiber-reinforced concrete mixture exhibits superior 28-day strength properties in spite of a 17 percent reduction in cement content and a 5 percent increase in the water-to-cement ratio. The improved reinforcing properties of processed cellulose fibers can be attributed to their crack suppression and stabilization characteristics.
Influence of Alkaline Earth Silicate Admixture on Durability of Pennsylvania Turnpike Bridges
Authors: Garvey John J. , Tikalsky Paul J. , Scheetz Barry , Grant Bruce
Published: April 2007

Chlorides from deicing salts are the primary cause of premature corrosion of reinforcement in concrete bridge decks. An alkaline earth silicate admixture (AESA) can reduce the permeability of concrete, preventing the ingress of chlorides, delaying the onset of rebar corrosion, and therefore increasing the design life of bridges. The performance of an AESA in bridge decks that have been in service for more than 25 years is compared with the performance of identical control bridges of comparable age. Visual inspection reveals serious deterioration in the control specimens. The decks of the control bridges reveal cracks, delaminations, and spalling in many of the precast deck panels. In the bridges with AESA, there is minimal visible deterioration. The goal of this research is to identify and characterize the effect of AESA on inservice bridge decks. Chemical and microscopic techniques are used to determine the nature of AESA in hardened concrete. Water and chloride ion permeability tests are performed to quantitatively determine the relative effects between control concrete and concrete containing the AESA. Testing has shown that AESA has chemical characteristics that enable it to react with portland cement and control the microstructural development in concrete. Quantitative tests for permeability and environmental scanning electron microscopy (ESEM) reveal a microstructure that is more continuous and interlocked than that of the control samples, indicating that the AESA reacts with cement to provide a microstructure that is less permeable.
Concrete Capillary Porosity as It Relates to Durability of Pavements Built with Alkali-Silica-Reactive Aggregates
Authors: Whiting Nancy M.
Published: April 2007

Several concrete pavements have been constructed in southwestern Minnesota using aggregates that recently have tested as being potentially deleteriously alkali-silica reactive. Standard ASTM test procedures were used. Most of these pavements fail to meet their design life. However, the rate of deterioration varies. Six pavement sites varying in age and performance were selected for comparison. Alkali-silica gel is present in all six pavements, even in the 36-year-old pavement still in good condition. Similar aggregate types were used for all six pavements. The coarse aggregate was a low-grade metamorphic quartzite, and the fine aggregate was a glacial sand obtained from various local sources. The relative capillary porosity of the concrete paste was examined using fluorescent dye epoxy impregnated with thin-section samples from each pavement site. Preliminary results suggest that the capillary porosity is linked to the durability of the concrete pavement. The best-performing concretes had a homogeneous capillary porosity that was moderate to low, and the poorer-performing concretes had paste with a capillary porosity that varied from high to low.
Market Dynamics and Nonwork Travel Patterns; Obstacles to Transit-Oriented Development?
Authors: Nelson Dick , Niles John S.
Published: April 2007

An essential tenet of the new urbanism is that existing as well as new activity centers of metropolitan regions should be developed to higher densities and a greater mix of uses. New urbanism suggests that if centers with different commercial functions are numerous and linked by high-quality transit service, people will significantly reduce their use of automobiles for both commuting and nonwork travel. Working against this ideal of transit-oriented development (TOD) as an organizing concept for urban design are strong market and socioeconomic forces that have created the current highly variegated commercial structure characteristic of urbanized areas in the United States. Results are reported of a preliminary exploration of retail industry decision making, consumer behavior, economic trends, and other key factors that have shaped the retail environment of metropolitan areas over the past 50 years. Well-known human motivations such as bargain hunting, comparison shopping, and variety seeking are reflected in the ongoing executive decision making and resource allocation by chain stores and multinational service institutions that increasingly dominate consumer markets. Efforts to reshape existing land use patterns often meet strong opposition from current residents. This complex of consumer, organizational, and political behavior could well constrain the vehicle travel reductions sought by proponents of new urbanism. Competitive retail industry practices and the associated consumer response are potential impediments to the success of TOD that should be addressed by metropolitan planners.
Framework for Analyzing Alternatives to Transit Bus Replacement
Authors: Khasnabis Snehamay , Naseer Mubashir
Published: April 2007

The addition of new buses to the existing fleet of any transit agency is a capital-intensive project. Approximately 50,000 transit buses are in service in the United States today that were purchased primarily through federal funds. In an average year, more than 3,500 buses are purchased by grantees of the Federal Transit Administration (FTA). A recent FTA study showed that, nationwide, the total annual cost of bus replacement easily exceeds $1 billion. An analytic framework for the assessment of alternatives to bus replacement is presented in this paper. Two generic groups of alternatives are identified: rehabilitation and remanufacturing. The former focuses on the repair of engines and machine components. The latter is more concerned with restoring the structural integrity of the bus. The framework developed uses the basic principles of economics and attempts to quantify benefits and costs associated with postponing the replacement of an existing bus either by rehabilitation or by remanufacturing. The procedure incorporates intangible benefits and disbenefits, as well as a risk penalty associated with the extended use of an existing bus beyond its normal service life. A set of examples is presented to demonstrate the application of the proposed framework. The examples show that the procedure is viable and can be used to assess the economic feasibility of alternatives to bus replacement.
Introducing Fare Simplification and New Convenience Fares at Connecticut Transit
Authors: Lee David A.
Published: April 2007

On June 28, 1998, the New Fare Deal was implemented in Connecticut, designed to make fare payment simpler and more convenient for customers. The program applied to three divisions of Connecticut Transit (CTTRANSIT) in Hartford, New Haven, and Stamford, as well as to other state-contracted transit services in Waterbury, New Britain, Bristol, Meriden, and Wallingford. The changes include elimination of local fare zones and the introduction of new convenience fares including 1- and 7-day passes. The fare changes were implemented in response to recommendations developed in a major market research study for CTTRANSIT, reported on in 1996, to encourage ridership in CTTRANSIT’s fastestgrowing market for suburb-to-suburb travel, to respond to the welfare-towork initiative, and to utilize more fully the features of the Ticket Reading and Issuing Machine (TRIM) equipment installed in 1995. Reviewed in this paper are what changes were implemented, why the changes were implemented, and what results have occurred to date. Detailed beforeand-after ridership data are not available. However, during the first 6 months following fare simplification, passenger revenue exceeded budget by about 3 percent (or almost $300,000), demonstrating that the anticipated revenue loss did not materialize. New convenience fare media have proved to be very popular.
Research-Based Transit Marketing in Southeastern Wisconsin
Authors: Bush Scott J.
Published: April 2007

Public transit systems need to retain current riders and constantly attract new customers. These systems require a continual investment of advertising resources to maintain and expand market share. Unfortunately, many transit agencies in southeastern Wisconsin have historically underfunded their marketing function. In face of the continual need to build ridership with inadequate marketing budgets, a partnership of four transit systems in southeastern Wisconsin and the Wisconsin Department of Transportation obtained a significant amount of advertising funds and completed a successful research-based marketing project in 1997. The project integrated formal market research with the creative advertising process to produce effective image and ridership-building campaigns. The research-based marketing approach developed up-front information to determine appropriate target audiences and messages for the advertising campaigns. The research also provided a formal evaluation tool to determine the effectiveness of the campaigns in regard to attitudes, awareness, advertising recall, and ridership. The advertising campaigns produced high-quality marketing materials that were visible, persuasive, and memorable. The multimedia campaign helped to improve opinions about public transportation, expand awareness of transit system service, increase ridership during and immediately following a special promotion, and support long-term growth in regional ridership. The partnership was a coordinated effort that enhanced the sophistication and effectiveness of transit marketing activities in southeastern Wisconsin. The success of the project has leveraged additional marketing funds that will be programmed to transit systems in the region.
Synergisms Among Land Use, Transit, and Travel Pricing Policies
Authors: Johnston Robert A. , Rodier Caroline J.
Published: April 2007

A review of empirical studies of the effects of land use on travel behavior leads to the conclusion that increasing density and mix can decrease vehicle kilometers of travel. The authors’ research project for the U.S. Environmental Protection Agency is outlined. Descriptions of the travel model used in the first phase of this research and of the emissions model and the traveler welfare model used in the study are given. The authors describe the six scenarios evaluated to date and the results of the simulations for the year 2015 for travel, emissions, and traveler welfare.
Toward a Policy on a Sustainable Transportation System
Authors: Richardson Barbara C.
Published: April 2007

As the world’s population increases and its resources remain constant, there is a need to address the sustainability of transportation systems. A sustainable transportation system is defined as one in which fuel consumption, vehicle emissions, safety, congestion, and social and economic access are of such levels that they can be sustained into the indefinite future without causing great or irreparable harm to future generations of people throughout the world. A wide range of factors influencing the conditions of sustainability is identified. These factors include, for example, market forces, low-price fuel, and vehicle-dependent land use patterns. Opportunities for policy intervention are identifiable through the influence diagrams developed. Participants in the transportation-use decision process and their possible actions and resultant consequences are discussed.
Fitting the FHWA Traffic Noise Model Noise Emissions for Use in STAMINA 2.0
Authors: Romick-Allen Richard K. , Lin Chiang , Morgan Susan M. , Bruns Michael T.
Published: April 2007

The recently released FHWA traffic noise model (TNM) and prediction program provides many improvements over the existing STAMINA program. However, the quick adoption of TNM could be hindered by its more detailed input, including the site terrain, and its relatively long run times. This paper examines updating the vehicle noise coefficients in STAMINA so that its use might be extended while the traffic noise community is being trained on TNM and while TNM’s weaknesses are dealt with. STAMINA has a well-documented deficiency of overpredicting traffic noise levels by about 3 dBA. This deficiency might be overcome by updating the vehicle noise emission coefficients. A recent source of traffic noise data is the 1995 reference energy mean emission levels (REMEL) study, which provides vehicle noise data for TNM. This paper presents the results of fitting the REMEL vehicle noise data to the STAMINA vehicle noise equation with a logarithmic regression. These updated noise coefficients are then tested with four example problems to evaluate the effectiveness of updating the STAMINA vehicle noise levels alone. The predicted noise levels from the updated STAMINA as well as the original 1975 noise levels are compared to the FHWA-TNM 1.0 predictions. The results show that the updated STAMINA reduces the overprediction relative to TNM by about 1.5 dBA. Updating only the vehicle noise coefficients, however, has little effect on the prediction of insertion loss because the STAMINA diffraction model was unchanged.
Development of an Assessment Process To Evaluate Sidewalk Accessibility
Authors: Axelson Peter W. , Wong Kathleen M. , Kirschbaum Julie B.
Published: April 2007

The Americans with Disabilities Act of 1990 mandates that public facilities such as sidewalks must be “accessible to and usable by” people with disabilities. A process for assessing the access characteristics of sidewalks was developed as part of a project to evaluate current conditions on sidewalks. This project is the Sidewalk Assessment Process. It was developed as a research tool for collecting objective information about sidewalk features such as grade and cross slope that impact pedestrian access. Measurements in cities across the United States were made to evaluate the accuracy of the process. It was determined from these measurements that accurate and reliable information about the accessibility of sidewalks could be collected using the process. The data were found useful to compare the dimensions of new construction and alterations on sidewalks with accessibility guidelines, to identify areas requiring additional maintenance to comply with standards, and to determine methods for solving access problems. The assessment process may be used as a stand-alone planning tool to help sidewalk professionals identify the means to improve pedestrian facilities in their jurisdictions or as part of a communitywide accessibility improvement program.
Wayfinding System for Transportation Services: Remote Infrared Audible Signage for Transit Stations, Surface Transit, and Intersections
Authors: Bentzen Billie Louise , Crandall William F. , Myers Linda
Published: April 2007

People who are print-disabled, who are blind, or who have other visual impairments are restricted in their ability to participate in public life because of lack of labels and signs in the environment. Currently, persons with severe visual impairments often require extensive assistance from strangers to travel in unfamiliar areas. Many other types of disabilities can prevent people from reading print. In addition to people who are blind or who have low vision, there are many head-injured, autistic, and dyslexic (or even just educationally impaired) people, along with persons who have had a stroke, who are not able to assimilate printed language even though they can see the page. Many people can accept the information through speech—that is, having print read aloud to them. Some human factors evaluations of a signage system specifically developed to aid people who have visual impairments or a print-reading disability gain information that is available to sighted people through print are described in this paper. This remote, infrared audible signage system—Talking Signs—is composed of a small infrared transmitter that emits a repeating voice message over a directional light beam to a handheld receiver carried by the blind pedestrian. The infrared system greatly reduces the need for travelers to remember distances, directions, and turns, thereby enhancing independence and efficiency in travel. Results show that remote infrared audible signage provides effective wayfinding information for using transit stations, surface transit, and intersections, thereby enhancing independent use of public transit by people who have visual impairments or cognitive disabilities.
Auto-Engaging Mobility-Aid Securement Systems and Low-Floor Buses
Authors: Hunter-Zaworski Katharine , Zaworski Joseph
Published: April 2007

The use of auto-engaging mobility-aid securement systems in regular transit operation on high- and low-floor transit vehicles in two cities was investigated in a demonstration project. The two cities were Eugene, Oregon, and Anchorage, Alaska. The impact of the new securement technology on vehicle operators, mobility-aid users, regular passengers, maintenance, and other transit staff was also investigated. Auto-engaging securement provides fast, safe, and independent mobility-aid securement for wheeled mobility aids. The auto-engaging securement systems were retrofitted on a select number of high-floor buses in regular transit service in Eugene, Oregon, and were factory installed on a fleet of new low-floor transit vehicles that were delivered to Anchorage, Alaska, for regular transit operations. Evaluation consisted of written and oral surveys administered to vehicle operators, mobility-aid users, regular passengers, and maintenance and other transit staff before, during, and after the demonstration project. The operational impacts of retrofitted and factory-installed securement systems were also compared. Auto-engaging securement systems show significant promise for use on highand low-floor transit vehicles. Auto-engaging systems do not delay the transit vehicle dwell time. In all tests the mobility-aid users were delighted with the independence and freedom of travel and felt much more secure in the auto-engaging securement systems than in the traditional belt securement systems.
Customer-Oriented Maintenance Decision Support System: Developing a Prototype
Authors: Alfelor Roemer M. , Hyman William A. , Niemi Gary R.
Published: April 2007

Performance of highway maintenance units has been traditionally measured by output or production rates. Today, more and more highway agencies are incorporating customer-oriented performance measures to evaluate their maintenance management processes. The Minnesota Department of Transportation (MnDOT) has been adapting and applying private-sector business practices to the management of its maintenance functions. The department initiated a maintenance business planning (MBP) project several years ago to focus on rethinking highway maintenance from the customer’s perspective. A prototype decision support system (DSS) was developed that builds on the MBP by modeling performance measurement parameters and implementing analytical processes that can support MnDOT’s maintenance managers in responding to customer needs. The DSS uses input, output, outcome, environment, and customer data from existing databases to measure efficiency and effectiveness of maintenance activities, as defined by the customer. The pilot system focuses on two of seven groups of maintenance products and services—clear roads and attractive roadsides. The prototype DSS displays data in formats useful for evaluating maintenance work processes, benchmarking work units’ performance, evaluating efficiency and effectiveness in meeting customer needs, and deploying resources. Models that calculate the value added to customers in terms of road-user costs (i.e., travel time and accident costs) and customer willingness to pay for attractive roadside products were developed and incorporated in the DSS. If fully implemented, the DSS can be a powerful tool for maintenance decision making that can be applied to other state maintenance agencies.
Resource Allocation Study for Snow Removal
Authors: Lindsey Rukhsana K. , Seely Michael S.
Published: April 2007

Each year the Maintenance Division of the Utah Department of Transportation spends more than 20 percent of its annual maintenance budget on snow removal. These funds cover labor, equipment, and material costs. The efficiency with which this money is spent depends on how the available resources are distributed. In the past, these resources have been distributed according to the past experience of the local engineers. Although this experience is invaluable, increasing demands on the maintenance budget make it necessary to reexamine how resources are distributed throughout the state. Widely varying conditions (from desert valleys to mountain summits) make a single standard impractical. This study integrates state-of-the-art geographic information systems technology, weather data, and experiences of local engineers to revise and update the current maintenance snow plan. After the snow plan has been revised, it will be periodically checked against measurements taken throughout the winter season to determine the areas that need more improvement. By using the revised snow plan, the Maintenance Division can maximize the use of its current assets and identify areas where improvements or new resources are needed.