ITC/USA 2010 Conference Proceedings / The Forty-Sixth Annual International Telemetering Conference and Technical Exhibition / October 25-28, 2010 / Town and Country Resort & Convention Center, San Diego, California / The requirements for a seismic telemetry-network are even more stringent than the well known problems of sensor networks. Existing medium access control (MAC) protocols suggest reducing energy consuming network activity by reducing costly transmissions and idle listening. Furthermore, it is required to set up communication patterns in different priority levels as well as ensuring fast handling of critical events. A protocol is proposed that operates with two parallel sets of time schedules in a time-division-multiple-access (TDMA) sense of periodic activity for listening and for transmitting. Synchronization packets sent from a central base station ensure optimal response times.

The purpose of this research is to develop a statistical method to monitor the fairness of network resource distribution. The newly developed fairness score function allows users to have the same or different priority levels. Especially, this function possesses all the necessary properties required as a quality characteristic for the purpose of statistical process control. The main objective is to find the critical values for the statistical test. Monte Carlo simulation is used to find the critical values. When the users have the same priority level, a table of the critical values is given for different sample sizes and different significance levels. When the users have different priority levels, it is difficult to generate a similar table since the users’ priority levels vary. Therefore, the critical values are computed for given priority levels. In both cases, an example is given to demonstrate the approach developed in this study.

Ring Barrier signal controller in VISSIM traffic simulation software provides different options for configuring Transit Signal Priority. This controller emulator allows for considering arterial progression by Priority Progression parameter; preferring specific transit signal priority calls to other calls by Priority Level feature; providing more green split to the signal priority phase by Green Extension attribute. This study aims to evaluate the impact of these three parameters on the performance of transit signal priority. The study area is based on three signalized intersections of Prices Fork Road in Blacksburg, Virginia. A total of five transit lines are assumed to request signal priority. Green Extension and Priority Level were found to have significant influence on bus delays, whereas bus frequency is not a significant variable to affect TSP effectiveness (for reducing the transit delays). This study also aims to identify the traffic conditions in which the adaptive feature of VISSIM Ring Barrier Controller can be most useful. Detector Slack, Detector Adjust Threshold, and Adjust Step are the parameters that should be hardcoded in the controller for activating the adaptiveness feature. The study area (Prices Fork Road in town of Blacksburg, VA) incorporates five bus lines are assumed eligible to request priority. This study revealed that transit service overlap can enhance or exacerbate each bus performance when transit signal priority is implemented, depending on the scheduled headways and the frequency of signal priority requests in each intersection. / Master of Science

Developments of commercial self-driving vehicle (SDV) technology has a potential for a paradigm shift in traffic control technology. Contrary to some previous research approaches, this research argues that, as any other technology, traffic control technology for SDVs should be developed having in mind improved quality of life through a sustainable developmental approach. Consequently, this research emphasizes upon the social perspective of sustainability, considering its neglect in the conventional control principles, and the importance of behavioral considerations for accurately predicting impacts upon economic or environmental factors. The premise is that traffic control technology can affect the distribution of advantages and disadvantages in a society, and thus it requires a framework of social justice. The framework of social justice is inspired by John Rawls' Theory of Justice as fairness, and tries to protect the inviolability of each user in a system. Consequently, the control objective is the distribution of delay per individual, considering for example that the effect of delay is not the same if a person is traveling to a grocery store as opposed to traveling to a hospital. The notion of social justice is developed as a priority system, with end-user responsibility, where user is able to assign a specific Priority Level for each individual trip with SDV. Selected Priority Level is used to determine the right-of-way for each self-driving vehicle at an intersection. As a supporting mechanism to the priority system, there is a structure of non-monetary Priority Credits. Rules for using Priority Credits are determined using knowledge from social science research and through empirical evaluation using surveys, interviews, and web-based experiment. In the physical space, the intersection control principle is developed as hierarchical self-organization, utilizing communication, sensing, and in-vehicle technological capabilities. This distributed control approach should enable robustness against failure, and scalability for future expansion. The control mechanism has been modeled as an agent-based system, allowing evaluation of effects upon safety and user delay. In conclusion, by reaching across multiple disciplines, this development provides the promise and the challenge for evolving SDV control technology. Future efforts for SDV technology development should continue to rely upon transparent public involvement and understanding of human decision-making. / Ph. D.