Field Of Transportation Engineering Research Articles

Inertial Effects during Impact Testing

Shortcomings were identified in historic dynamic guardrail post testing methods that could overestimate the strength of guardrail posts by a factor of two. This inaccuracy resulted from the influence of inertia that was not previously accounted for during dynamic component testing. The effects of inertia were verified and quantified with several analysis methods including nonlinear finite element analysis, which was used to develop a computer simulation of the dynamic tests. Several alternative testing procedures that could significantly reduce the effects of inertia were identified and investigated. One of these testing alternatives–-use of a crushable impact head–-was shown with computer simulation to reduce the effects of inertia and maintain the benefits of strain rate effects. The use of such an impact head is recommended for all future dynamic post strength testing. The results of the study imply that changes should be made not only in the standard design procedures used for guardrail and other vehicular barriers, which are clearly influenced by inertial effects, but in all designs that are based on dynamic strength testing. Dynamic testing is very common in the field of transportation engineering and care should be taken to ensure that inertial effects are considered when performing such tests.

Petroleum Prices and Transportation Engineering

The recent increase in global petroleum prices marks a major turning point in the modern history of transportation. The U.S. price of regular gasoline has increased 100% from June 2004 to June 2008, reaching nearly $4/gallon Energy Information Agency 2008 . In June 2008, the price of a barrel of crude oil exceeded US$120 €77 . The petroleum price increase was particularly noticeable in the United States, where it coincided with a fall in the value of the dollar on international monetary exchange markets, but the increase was certainly a global phenomenon. There have been other temporary surges in the price of petroleum, notably the increase associated with the Organization of the Petroleum Exporting Countries OPEC oil embargo in the early 1970s. It could be that the recent surge in petroleum prices is due in part to speculative trading on the future price of oil, and the petroleum price could drop in the near term. However, increasing worldwide vehicle ownership and travel has led to surging demand for petroleum. World consumption of crude oil has now reached 1000 barrels per second Tertzakian 2006 . At the same time, new supplies of petroleum are both smaller than past discoveries and require more resources to extract. As a result, the increase in petroleum prices seems to be a long lasting phenomenon. Similar price increases have affected other supplies of energy, such as coal and natural gas. After decades of low energy costs, we face an era of much higher energy expenses. Reactions to the higher price of petroleum are already being seen in the marketplace. In the United States, vehicle purchases are shifting to smaller and more fuel-efficient vehicles. Vehicle miles of travel are expected to drop in the United States in 2008. Airlines throughout the world are raising fares to compensate for higher fuel prices. International freight tariffs are experiencing similar increases. The increased price of petroleum and the resulting transport changes have at least one silver lining: they will likely reduce the emission of greenhouse gases responsible for global climate change. Even without higher petroleum prices, there are new proposals for charges and restrictions on carbon emissions. Fig. 1 shows the equivalent fuel economy of the European Union and California Carbon Dioxide emission standards for passenger vehicles, where the carbon emission standard is converted into required fuel efficiency. In both cases, the carbon emission standard represents better fuel economy than the widely discussed new Corporate Average Fuel Economy Standards in the United States. Both carbon emission restrictions and the higher costs of fuel consumption motivate both more efficient vehicles and nonpetroleum-based alternative fuels. What does this historic turning point in transportation mean for the field of transportation engineering and for the Journal of Transportation Engineering in particular? In short, we have work to do. Most of the past practice and research in transportation engineering has assumed reliance on petroleum for transportation

An expert system for risk assessment of automobile crashes

There is an ongoing concern to make Alabama roadways a safer place to travel. The purpose of this research is to help in this effort. Identification of critical accident characteristics based on previous accident data helps to identify areas where safety efforts should be directed. Early recognition of critical crash characteristics represents the most efficient way to reduce the occurrence of traffic-related accidents. However, a major obstacle to the assessment of risk is the inability to provide necessary information concerning accident analysis. The objective of this research was to develop a computer-based expert system for risk assessment of automobile accidents. The Expert System for Risk Assessment of Automobile Crashes (ExRAAC) assesses accident characteristics based on inputs by the user. The system emulates the thought process of an expert, in the field of transportation engineering, in assessing the result of such an automobile accident. This expertise is represented in the knowledge base of the system using If–Then rules. The expert system asks the user questions regarding the characteristics of the accident, and based on the answers, assesses whether the accident will result in a 'fatality', 'injury' or 'no injury no fatality'. It also gives the probability of the occurrence of such an accident. The critical characteristics of the accident can then be further analysed to discover areas where safety efforts should be directed in order to prevent such a crash.

A Fuzzy Approach for Traffic Flow Control

The modern road infrastructures must face the phenomena of traffic congestion. Such phenomena are at the origin of the deterioration of the life quality with its problems of health and of the damage caused with the environment. This requires a design and implementation of efficient control strategies to reduce or minimise the effect of traffic congestion. This paper deals with the use of fuzzy approach as a basis tool to elaborate strategies for traffic flow control. The perspective with such works is to provide a decision support allowing to help the active actors in the field of transportation engineering.

Fashioning one-way urban road network design as a Module Orientation Problem

Conversion of 2-way roads to 1-way roads or vice versa is not an unusual practice in the pragmatic field of transport engineering. However, there have been few if any mathematical theories developed to investigate the optimal layout of the road network during the conversion of 2-way roads to 1-way roads. This paper discusses fashioning 1-way urban road network design as a Module Orientation Problem (MOP), thereby suggesting various solutions employed in the MOP could be used in the design of 1-way urban road networks. As an illustration, the graph model approach provided by Cheng et al. (1991) is used to formulate the 1-way urban road network design as an MOP. Results obtained are run and further validated using a traffic simulation package, Paramics.

Reinforcement learning: Introduction to theory and potential for transport applications

The aim of this paper is to develop insight into the potential of reinforcement learning (RL) agents and distributed reinforcement learning agents in the domain of transportation and traffic engineering and specifically in Intelligent Transport Systems (ITS). This paper provides a crystallized, comprehensive overview of the concept of RL and presents related successful applications in the field of traffic control and transportation engineering. It is divided into two parts: the first part provides a thorough overview of RL and its related methods and the second part reviews most recent applications of RL algorithms to the field of transportation engineering. Finally, it identifies many open research subjects in transportation in which the use of RL seems to be promising.Key words: reinforcement learning, machine learning, traffic control, artificial intelligence, intelligent transportation systems.

Computing with Bees: Attacking Complex Transportation Engineering Problems

The Bee System (an artificial bee swarm) is introduced in this paper. The proposed approach is applied to the Traveling Salesman Problem. The obtained results are very promising. The potential applications of the developed Bee System in the field of transportation engineering are discussed. The Bee System represents the new, successful application of emergent techniques based on natural metaphors, such as simulated annealing, genetic algorithms, and neural networks, to the complex engineering and management problems.

Review of Transportation engineering basics by A. S. Narasimha Murthy and Henry R. Mohle

This book is written as a lab manual to show students how to apply classroom knowledge and principles to real-world problems in the field. Used in conjunction with a transportation engineering text book, this book can help students to understand What type of work will I be doing? and How can I apply this specific knowledge to the project that I’m doing? The book presents its content in the form of a series of labs. The first part of the book covers common traffic engineering studies, such as a spot speed study, turning movements, and volume study, saturation flow study, travel time study, and delay study. Practical topics on parking analysis, pedestrian and bicycle facilities are also discussed. Guidelines and procedures for field data collection and work sheets for data collection, reduction, and summary are included in many labs. A set of questions for improving the definition and the scope of the study, practicing the procedure of field work, and formulating conclusions and recommendations are provided at the end of each lab. The passing of the Transportation Equity Act for the 21st Century ~TEA 21! has presented new opportunities for transportation professionals, and also specified new requirements in many different areas within the field of transportation engineering. In response to the new focuses set by TEA 21, 10 new labs are added to this second edition. Those new labs cover advanced practical

A Multimedia Approach to Transportation Education

Multimedia application software is making a phenomenal impact in the desktop computer industry. The potential benefit of multimedia in education is clear but still remain largely unexploited. Although educational institutions make extensive use of PCs in the context of application software little consideration has been given to extending their effective use in computer aided learning (CAL). This paper describes an experimental teaching package for use on undergraduate and postgraduate courses, and for industrial training in the field of transportation engineering. The development of a multimedia course delivery system is outlined, followed by a description of an example application. The paper concludes with a discussion on further developments.

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