Transportation Science
Công bố khoa học tiêu biểu
* Dữ liệu chỉ mang tính chất tham khảo
Sắp xếp:
The Uniqueness of a Time-dependent Equilibrium Distribution of Arrivals at a Single Bottleneck Motorists going through a bottleneck during the morning rush hour have to time their departure times to ensure they arrive to work at a reasonable time. Traffic and congestion levels at the bottleneck depend on the motorists' work schedule and the disutility of unpunctuality. This paper shows that, under certain conditions, there is only one equilibrium order of arrivals; an order under w... ...
Transportation Science - Tập 19 Số 1 - Trang 29-37 - 1985
Properties of Dynamic Traffic Equilibrium Involving Bottlenecks, Including a Paradox and Metering D. Braess and others have shown that creating a new link in a congested network, or adding capacity to an existing link, can raise total travel costs if drivers switch routes. Here we show that a paradox can also result when routes are fixed, but users choose when to travel. As is true of the Braess paradox, the paradox here arises when the inefficiency due to underpricing of congestion i... ...
Transportation Science - Tập 27 Số 2 - Trang 148-160 - 1993
Average Delay at an Unsignalized Intersection with Two Major Streams Each Having a Dichotomized Headway Distribution The average time a driver has to wait before he can cross two major streams has been a major performance indicator for unsignalized intersections. The equations presented in this paper give an estimate of this average delay as a function of the average delay to isolated minor stream vehicles (Adams' delay) and the degree of saturation of the minor stream (minor stream entry flow/maximum e... ...
Transportation Science - Tập 20 Số 4 - Trang 272-286 - 1986
Perceptual Thresholds in Car-Following—A Comparison of Recent Measurements with Earlier Results The authors have previously conducted a field experiment to investigate the sensitivity of subjects to the sign of relative motion when following a vehicle. They interpreted their results in terms of responses to analytical functions of relative speed divided by spacing, or spacing change divided by spacing. In the present paper the remits of a number of other field, simulator, and labora... ...
Transportation Science - Tập 11 Số 1 - Trang 60-72 - 1977
Characterizing Traffic Conditions in Urban Areas A series of vehicular traffic experiments conducted in Austin, Texas, shows the reasonableness of the two assumptions in the two-fluid (moving and stopped vehicles) model of town traffic. The observational data support the assumption that the average speed in an urban street network is proportional to the fraction of the vehicles moving raised to a power and is also in agreement with the ... ...
Transportation Science - Tập 18 Số 2 - Trang 101-140 - 1984
An Adaptive Dynamic Programming Algorithm for Dynamic Fleet Management, I: Single Period Travel Times We consider a stochastic version of a dynamic resource allocation problem. In this setting, reusable resources must be assigned to tasks that arise randomly over time. We solve the problem using an adaptive dynamic programming algorithm that uses nonlinear functional approximations that give the value of resources in the future. Our functional approximations are piecewise linear and natur... ...
Transportation Science - Tập 36 Số 1 - Trang 21-39 - 2002
Vehicle Routing with Stochastic Demands: Properties and Solution Frameworks This paper considers the vehicle routing problem with stochastic demands. The objective is to provide an overview of this problem, and to examine a variety of solution methodologies. The concepts and the main issues are reviewed along with some properties of optimal solutions. The existing stochastic mathematical programming formulations are presented and compared and a new formulation is... ...
Transportation Science - Tập 23 Số 3 - Trang 166-176 - 1989
Computational Approaches to Stochastic Vehicle Routing Problems We report computational test results for several graph-based a priori heuristics for the Euclidean plane versions of two well-known stochastic optimization problems, the probabilistic traveling salesman problem (PTSP) and the probabilistic (or stochastic) vehicle routing problem (PVRP). These heuristics are termed a priori because they design vehicle routes prior to realization of demands... ...
Transportation Science - Tập 29 Số 4 - Trang 342-352 - 1995
Technical Note—Heuristics for Delivery Problems with Constant Error Guarantees In this paper Q Iterated Optimal Tour Partitioning, and Best Optimal Tour Partitioning algorithms are studied and analyzed for their worst case error. Both algorithms are based on partitioning an optimal traveling salesman tour in order to generate a feasible solution to the unit weight delivery problem. They have a worst case error bound of 2 − 1/Q where Q is the maximal number of custom... ...
Transportation Science - Tập 24 Số 4 - Trang 294-297 - 1990
An Adaptive Dynamic Programming Algorithm for the Heterogeneous Resource Allocation Problem We consider an aggregated version of a large-scale driver scheduling problem, derived from an application in less-than-truckload trucking, as a dynamic resource allocation problem. Drivers are aggregated into groups characterized by an attribute vector which capture the important attributes required to incorporate the work rules. The problem is very large: over 5,000 drivers and 30,000 lo... ...
Transportation Science - Tập 36 Số 2 - Trang 231-249 - 2002
Tổng số: 87
- 1
- 2
- 3
- 4
- 5
- 6
- 9