Recurring traffic congestion is attributable to steadily increasing travel demand coupled with constrained space and financial resources for infrastructure expansion. Another major source of congestion is non-recurrent incidents that disrupt the normal operation of the infrastructure. Aiming to optimize the utilization of the transportation infrastructure, innovative infrastructure management techniques that incorporate on edge technological equipment and information systems need to be adopted to manage recurrent and non-recurrent congestion and reduce their adverse externalities. The framework presented in this thesis lays the foundation for multi-disciplinary semantic web based incident management. During traffic incident response, involved stakeholders will share their knowledge and resources, forming an ad-hoc framework within which each party will focus on its core competencies and cooperate to achieve a coherent incident management process. Negotiation between various response agencies operators is performed using intelligent software agents, alleviating the coordination and synchronization burden of the massive information flow during the incident response. The software agents provide a decision support to human operators based on the reasoning provided from the underlying system knowledge models. Ontological engineering is used to lay the foundation of the knowledge models, which are coded in a web based ontology language, allowing a decentralized access to various elements of the system. The whole system communication infrastructure is based on the Semantic Web technologies. The semantic web facilitates the use of, in an enhanced manner, the already existing web technologies as the communication infrastructure of the proposed system. Its semantic capabilities help to resolve the information and data interoperability issues among various parties. The web services concepts combined with the semantic web allow the direct exploration and access of knowledge models, resources, and data repertories held by various parties. The developed ontology along with the developed software system were tested and evaluated by domain experts and targeted system users. Based on the conducted evaluation, both the ontology and the software system were found to be promising tools in developing pervasive, collaborative and multi-disciplinary traffic incident management systems

Recurring traffic congestion is attributable to steadily increasing travel demand coupled with constrained space and financial resources for infrastructure expansion. Another major source of congestion is non-recurrent incidents that disrupt the normal operation of the infrastructure. Aiming to optimize the utilization of the transportation infrastructure, innovative infrastructure management techniques that incorporate on edge technological equipment and information systems need to be adopted to manage recurrent and non-recurrent congestion and reduce their adverse externalities. The framework presented in this thesis lays the foundation for multi-disciplinary semantic web based incident management. During traffic incident response, involved stakeholders will share their knowledge and resources, forming an ad-hoc framework within which each party will focus on its core competencies and cooperate to achieve a coherent incident management process. Negotiation between various response agencies operators is performed using intelligent software agents, alleviating the coordination and synchronization burden of the massive information flow during the incident response. The software agents provide a decision support to human operators based on the reasoning provided from the underlying system knowledge models. Ontological engineering is used to lay the foundation of the knowledge models, which are coded in a web based ontology language, allowing a decentralized access to various elements of the system. The whole system communication infrastructure is based on the Semantic Web technologies. The semantic web facilitates the use of, in an enhanced manner, the already existing web technologies as the communication infrastructure of the proposed system. Its semantic capabilities help to resolve the information and data interoperability issues among various parties. The web services concepts combined with the semantic web allow the direct exploration and access of knowledge models, resources, and data repertories held by various parties. The developed ontology along with the developed software system were tested and evaluated by domain experts and targeted system users. Based on the conducted evaluation, both the ontology and the software system were found to be promising tools in developing pervasive, collaborative and multi-disciplinary traffic incident management systems

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Abstract The purpose of this thesis is to fabricate l = 1.55mm ridge waveguide spot size converter lasers for high laser-to-fiber coupling. The laser structure design includes the lateral and vertical directions. In the vertical aspect, we use six asymmetric InGaAsP/InP quantum wells of 50, 50, 100, 100, 150, 150Å. The asymmetric multi-quantum-well structure is designed to gather the optical field in the 150Å-wide quantum wells. Besides, we add a passive waveguide near the 150Å-wide quantum wells to expand optical field profile. In the lateral aspect, we use tapered ridge waveguides which have two different fashions: one is tapered down from 2.5mm to 1mm, and the other is tapered up from 2.5mm to 4mm. The results show that the tapered-up ridge waveguide laser has a CW operation with Ith = 34mA and diverge angles of 14¢X¡Ñ36¢X (q//¡Ñq^) at room temperature. The tapered-down ridge waveguide laser exhibits only a pulsed operation at room temperature. At lower temperature T = 13¢XC, the tapered-down laser has a CW operation of Ith = 36mA and diverge angles of 14¢X¡Ñ36¢X(q//¡Ñq^). From I-V and C-V measurements, we attribute the heating problem to the large series resistance caused by the incorrect n-type doping profile in the epitaxy process.

This project was designed to determine the feasibility of constructing a multichamber proportional counter. A multi-chamber detector is designed to increase the total surface area which will increase the number of radiation interactions that occur per unit dose. Surface area can be changed without changing the detector volume by subdividing the active volume into several smaller volumes that can then be used as mini detectors whose data can be summed and used to determine the absorbed dose. This will allow the total surface area to remain the same as that of the more common 12.5 cm (5 in.) spherical detector and a decreased total volume resulting in a more compact detector design. However, subdividing those volumes causes problems with electric field fringing at the ends of the mini detectors. In order to correct this, guard ring and field tube designs which operate at a lower voltage than the detector cathode were tested. Results from this study showed that the field tube design provided the best overall resolution but it only outperformed the other designs by a maximum of 5%. However the field tube design doubles the length of the detector which would result in a larger overall detector package. The performance of the single and double ring configurations was suitable for radiation monitoring applications. These findings show that it is feasible to use an array of subdivided detector volumes instead of a spherical detector.

This thesis will investigate the impact of the use of the Phasor Measurement Units (PMU) on the state estimation problem. First, incorporation of the PMU measurements in a conventional state estimation program will be discussed. Then, the effect of adding PMU measurements on the state estimation solution accuracy will be studied. Bad data processing in the presence of PMU measurements will also be presented. Finally, a multiarea state estimation method will be developed. This method involves a two level estimation scheme, where the first level estimation is carried out by each area independently. The second level estimation is required in order to coordinate the solutions obtained by each area and also to detect and identify errors in the boundary measurements. The first objective of this thesis is to formulate the full weighted least square state estimation method using PMUs. The second objective is to derive the linear formulation of the state estimation problem when using only PMUs. The final objective is to formulate a two level multi-area state estimation scheme and illlustrate its performance via simulation examples.

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