Disaggregate simultaneous urban travel demand models: A brief introduction

This paper is intended to provide a general background to the two following papers, A Simultaneous Destination and Mode Choice Model for Shopping Trips and Some Estimation Results of a Simultaneous Model of Auto Ownership and Mode Choice to Work. Some of the deficiences of the conventional urban transport modelling system are reviewed and a case is made for the use of simultaneous models estimated with disaggregate data.     

Optimal Linear Active Suspensions with Integral Constraint

This paper considers the application of linear optimal control to the design of an active automobile suspension system. By inclusion of an integral constraint in the performance index it is possible to achieve zero steady state axle to body response to both static body forces and ramp road inputs. Full state feedback is achieved by reconstructing the state variables from easily measured quantities.     

An analysis of elevator operation in moderate height buildings—I: A single elevator

Approximate analytic methods are used to describe how the equilibrium trip time of an elevator depends upon the physical characteristics of the elevator, the passenger demand, and possible strategies of operation. The analysis is directed particularly toward elevators in buildings of moderate height (10–15 floors) at traffic levels such that the elevator is seldom idle or fully loaded. Part I describes the model and the general method for estimating means and variances of trip time if a group of floors is served by only one elevator and passenger arrivals define a homogeneous Poisson process.     

Symbolic-numerical Solution of Multibody Systems with Closed Loops

For multibody systems with closed kinematic Loops a set of ordinary differential equations and decoupled algebraic equations is formulated which can be solved with explicit multistep integration algorithms. This is achieved by introducing a minimal set of generalized coordinates being specified during numerical integration. For avoiding restart of the integration algorithm after changing these variables transformation relationships are given. Velocity and acceleration constraints are satisfied exactly, position constraints are fulfilled approximately by a dynamic invariant projection onto the constraint manifold. The method is demonstrated by an application to a five-point wheel suspension.     

Transport studies research in U.K. universities

British universities have entered a period of crisis. The outward manifestation of the current malady has appeared as a general cut-back in university spending. Until two or three years ago, most universities looked forward to a modest growth in activity. This has now been changed and the expectations of growth have been replaced by the reality of consolidation and modest decline. However, the universities are not alone in their dilemma. The general downturn in economic prosperity has left few institutions unscathed. Most universities, both in Britain and abroad, have therefore been forced to review their expectations and their ongoing commitments in teaching and research. The review of university activity goes much deeper than the immediate problems of finance. The current soul-searching has been sparked off by the crisis of finance, but has roots which go much deeper and touch on the very fundamentals of university education itself. In a sense, one is witnessing a belated form of public accountability: what is the purpose of a university; should its subjects be demonstrably relevant (both in themselves, as well as in their capacity to prepare students for a career); should universities engage in research and, if so, should it complement their teaching functions or be additional to it? These, and many other issues, are currently being discussed, and it is specifically with reference to their role in the field of transport research that this paper is addressed.     

Mechanisms for the control of transnational shipping corporations

The author presents a model of the conflicts that arise in the transnational shipping industry with special emphasis on control alternatives during entry into shipping operations. He concludes that, since transnational shipping is a non-zero sum game, gains can be created for world shipping as a whole.     

Locating and sizing park-ride lots with interactive computer graphs

Two alternative methods for conducting a preliminary analysis of the problem of locating and sizing park-ride lots for an urban bus transit system are examined. These alternative methods are tested using a large and complex street network representing the northern half of the City of Seattle, Washington. Four design criteria are identified and an overall measure of system performance is devised. The problem is to determine the size and location of three park-ride lots that will maximize the performance of the system. The first method utilizes a computing system called LOCATOR II in an interactive graphic mode. In an experimental setting, five students use LOCATOR II to locate three park-ride lots and their solutions are found to exhibit a very high average level of performance. The second method does not involve a direct interaction with the computing system but does use LOCATOR II in a batch mode. Several students participate in three rounds of the batch mode experiment and the performance of their designs is somewhat poorer than the designs found in the interactive graphics experiment. Overall, the experimental results show that relatively inexperienced persons can find a high performance design for a reasonably complex problem quickly and inexpensively. These designs can provide a good starting point for the detailed consideration of many of the other aspects of the problem of providing a high performance bus transit service in an urban area.     

Applying the Value-Belief-Norm Theory to Marine Contexts: Implications for Encouraging Pro-Environmental Behavior

Encouraging pro-environmental behavior among protected area visitors and other stakeholders has become a priority for marine resource managers. However, there exists a lack of understanding of the human dimensions of resource management regarding the perceptions and attitudes of stakeholders. Using the value-belief-norm theory of environmentalism (VBN) as a framework, the purposes of this investigation were to: 1) test a model of variables that influence stakeholders' intentions to adopt pro-environmental behavior in two marine protected areas (i.e., the Great Barrier Reef Marine Park and the Florida Keys National Marine Sanctuary); and 2) using the relevant literature and information gleaned from the model, suggest techniques that managers can use to encourage pro-environmental intentions. Acceptable goodness-of-fit indices for both of the structural equation models (one for each protected area) provided empirical support for the usefulness of the VBN framework to guide both research in marine contexts and marine protected area management efforts to encourage stakeholders' intentions to engage in pro-environmental behavior. Specific suggestions include increasing stakeholders. knowledge about impacts via environmental education strategies, increasing their awareness of their impacts and their efficacy in mitigating those impacts (e.g., workshops), and developing interpersonal relationships among managers and stakeholders (e.g., implementation intention and follow-up strategies).