Factors influencing support for local transportation sales tax measures

Sales tax measures passed at the local level and dedicated to transportation projects have become increasingly popular in the United States. While revenues from fuel taxes stagnate, growth of local transportation sales taxes (LTSTs), most approved in local elections, has led to a gradual shift of the financial base for transportation projects away from user fees and toward broader-based taxes. In this study, the relationship between voter support and the social, political, and geographic characteristics of the voters is explored. Using precinct-level voting data and census demographic data for three local transportation sales tax elections in Sonoma County, in the San Francisco Metropolitan area of California, regression models were constructed to analyze this relationship. In addition, the relationship between the outcomes of the three measures was explored to better understand which transportation projects might have garnered more support for the successful measure. It was found that the closer voters lived to the transportation projects to be funded, the greater their support. Higher incomes were also positively related to support, controlling for other variables. Political leanings were found to affect support, with the direction of the effect dependent upon the project list in each measure’s expenditure plan. Finally, it appears that the latest measure, which passed successfully, benefited greatly from its multi-modal expenditure plan.     

Automated Emergency Four-Wheel-Steered Vehicle Using Continuous Gain Equations

Advanced Vehicle Control Systems (AVCS), when realized, should substantially increase the convenience and safety of highway travel. Automated lateral control is an important step in the realization of AVCS. Much research has been concerned with lateral control during low-g maneuvers. However, before passengers' lives are in the hands of any automated laterally-controlled vehicle, the vehicle controller must be designed to respond to emergency situations where high-g maneuvers may be necessary.

This paper presents the development of a nonlinear-gain-optimized (NGO) controller for emergency automated lateral control of four wheel steered automobiles. Continuous gain equations (GE) are used to account for changes in the vehicle speed. The NGO controller uses a linear vehicle/tire model to define the state model. The response of a nonlinear vehicle/tire model is used to choose the performance index that optimizes the feedback gains for high-g emergency maneuvers at discrete speeds. Continuous gain equations are then derived as least-square approximations to each set of gains.

The performance of the four-wheel-steer continuous gain equations (4WS-GE) controller is compared to that of a two-wheel-steer continuous gain equations (2WS-GE) controller. Significant improvements in vehicle response are realized by using the 4WS-GE controller. The robustness of the controller's performance is examined with respect to changes in tire parameters and changes in vehicle mass.     

Short sea shipping

This paper quantifies the potential environmental benefit of short sea shipping. Critical strategic issues relevant to formulating public policy are developed. Coastal shipping has traditionally been a major sector of the maritime industry. This continues to be the case in the European Union, but the sector has diminished in relative importance in North America as the transport industry has become increasingly dominated by less environmentally-friendly interstate trucking and railroads. Congestion threatens to overwhelm overland carriage and limit economic growth. An alternative strategy is to revitalize coastal shipping as short sea shipping to alleviate traffic congestion and enhance economic development by maintaining freight flow efficiency. Because ship transport offers higher fuel economy and lower emission of harmful pollutants, the environmental benefits of short sea shipping over land transportation can be quantified and used to inform public policy.     

Changes in perceived travel cost and time for the work trip during a period of increasing gasoline costs

This study was designed to examine the relationship between actual and perceived values of cost and time for the work trip and to examine how perceptions have changed over a period of dramatically increased travel costs. Variations in the relationship between perceived and actual values were examined as a function of situational and attitudinal variables. Two telephone surveys were conducted one year apart (Fall 1978 and Fall 1979). On the next working day following a survey, a research assistant recreated the respondent's work trip, recorded time values and used distance measures, car type information and parking costs to compute travel cost. The first survey revealed that most auto users were unable to articulate dollars-and-cents driving costs for the work trip, but auto users in the second survey were able to provide fairly accurate cost estimates. Dramatic changes in fuel prices between surveys is probably the main reason for the change in driving cost awareness. Auto users were also asked to rate relative costs of driving a car compared to using the bus for the work trip. These ratings showed that auto users tended to underestimate driving costs relative to bus costs, but this tendency decreased from the first to the second time period. Commuters in all modal groups at both time periods tended to overestimate travel times. Perception of travel time varied as a function of mode, perceived comfort (for car users), and perceived convenience and number of transfers (for bus users).To whom correspondence should be addressed.     

The impact of the Merchant Marine Act of 1970 on subsidized US ship construction

The United States Congress reasserted the desire for continued financial support to domestic merchant-ship construction when in 1970 it amended the Merchant Marine Act of 1936 [1]. With regard to the shipbuilding industry, the most significant changes contained in the Merchant Marine Act of 1970 [2] are those designed to reduce the construction differential subsidy and to increase the variety of vessels that might be subsidized. Sections 501(a), 502(a), and 502(b) of the 1936 Act were amended to facilitate the reduction in subsidies; Section 905(a) was modified to encourage the subsidized construction of liquid and dry bulk cargo vessels. After a cursory review of the 1970 amendments to the 1936 Act, this paper is directed to ascertaining the results, in general, of the changes and whether they have generated increased domestic shipyard productivity and lower subsidy rates.     

Views on transit tax financing in the U.S.

Transportation - Although much has been written about the economics of transit tax financing, public views and opinions toward alternative tax sources have received comparatively short shrift. This...     

Candian port administraion: its future structre

The administration, management and development of ports in Canada is a Federal government responsibility. This centralist control of ports has been the subject of criticism by many for a variety of reasons, not the least of which is that it is not responsive enough to the affairs of the local level. This problem, along with others, has resulted in the introduction in the Canadian Parliament of proposed legislation over the past five years to alter port administration and development in Canada. The proposals culminated in the recent passage of the Canada Ports Corporation Act which, among other things, will see the abolition of the National Harbours Board. A review of the administrative structure the new Act replaces, along with a review and assessment of the Act itself and the proposed legislation which predated it, forms the basis of this paper. It will be seen that because of the new Act the centralist approach to port administration is maintained, but greater local autonomy and financial self-sufficiency will also be available to ports. However, the central administration will still have the problem of co-ordinating the development of Canadian ports, since ports will continue to be constituted under at least four different pieces of legislation.     

A path-based user-equilibrium traffic assignment algorithm that obviates path storage and enumeration

This paper presents a novel user-equilibrium (UE) traffic assignment algorithm, which under conventional assumptions, promises to compute UE arc flows to acceptable precision, regardless of the network’s topology, size or congestion:

• The algorithm takes the simple approach of shifting flow from a costliest path to a cheapest path until the costs of all used paths are within a given of the cheapest.

• Because of being path-based, it avoids tailing.

• In spite of being path-based, it neither stores nor enumerates paths.

• These efficiencies derive from decomposing the problem into a sequence of easy single-origin problems on acyclic sub-networks.

Solutions to this sequence of sub-network flows converge rapidly to a sharp practical estimate of UE arc flows—as is amply demonstrated by tests using the Chicago region’s 40,000-arc network model.     

On the kinematics and quantum dynamics of traffic flow

The hydrodynamic model of traffic flow is presented and interpreted. Traffic dimensions are defined for the dynamic entities of flow and the behaviour of congestive and dispersive flow is discussed dependent on the value of the local traffic transfer number, R. The wave equation is one example of dispersive flow, where quantum numbers define the condition of free flow at the endpoints of the link. The Schrödinger equation is defined and applied to the study of the cyclic work journey and the problem of traffic lights as an harmonic oscillator.     

Bridge and tunnel toll elasticities in New York

In 1992, the authors carried out a statistical analysis of Triborough Bridge and Tunnel Authority (TBTA) crossings in New York City, to determine the impact of toll increases on traffic volumes and revenue. Using twelve years of monthly time-series data, we developed a set of multiple regression models that estimated traffic volumes on each TBTA bridge and tunnel as a function of the toll level and other explanatory variables. In most cases, the estimated toll elasticities were negative and much less than 1.0 in absolute value; the median toll elasticity for automobiles was found to be –0.10. Our finding that automobile travel demand is highly inelastic with respect to toll rates is consistent with most previous travel demand studies.