A method of generating and testing pseudopotentials will be presented. This required the development of PPTester, a custom software program to analyze and quantify various parameters. These methods were first used to study bulk Si and verify the installation and performance of SIESTA. Plots, which agreed with published results, for band gap and charge density were generated.Next, pseudopotentials for Cd and Se were constructed and tested. Two separate Cd potentials were evaluated. Electronic structure calculations for two, four and six atom small cadmium selenide (CdSe) colloidal quantum dots were performed. The changes in geometry of initial versus relaxed atomic positions of these systems were evaluated. Output values of the electronic structure calculation, for example Fermi energy, were analyzed. / Department of Physics and Astronomy

Starspots are not well understood for contact binary star systems. The following properties of spots were systematically investigated: temperature, radius, colatitude, and longitude. Spots were modeled on an AE Phe like contact binary system. The spots were changed in a systematic manner. The light curve phases of primary minimum and primary maximum were affected by these parameter changes in a systematic manner, as well as the secondary minimum and maximum. It will be shown that it is possible to use the shift in these phases to study starspots over time. This information can also be used to identify the presence of spots in binary star systems.Starspots on contact binary systems are not commonly found at a longitude near 180°. The results of this study show that starspots near 180° should be the easiest to detect using photometric techniques. This is the most significant result from this study. Either there is an unknown physical reason why contact binary stars do not have starspots near a longitude of 180°, or the starspots are there and the photometric data has been misinterpreted. / Department of Physics and Astronomy

Thesis (M.App.Sc.) - Carleton University, 2002. / Includes bibliographical references (p. 80-81). Also available in electronic format on the Internet.

M.Ing. / Previous research have entailed developing various network traffic models which describe network traffic behaviour, but no model describes differential traffic treatment to such an extent to be able to relate the impact different rates have on the various traffic classes. The main reason for this being the amount of parameters that needs to be taken into consideration. Previous research performed in this field, analysed certain schedulers according to fixed parameters, thus having a very limited results base. No detailed comparison of these schedulers behaviour in a Differentiated Services (DiffServ) environment is available since the parameters under which their analysis were performed are different. A first objective entailed performing a thorough literature survey concerning DiffSery to summarize the research material that is available. This gives us as well as the reader a foundation to start any future research and the means to make good use of this information. Secondly, a DiffSery module was ported from an old version of Ns-2 which was developed for an older Linux kernel and GCC version; to the newest available. Ns-2 was also limited in respects to traffic generation. We developed a traffic generator that generates traffic according to a certain statistical distribution. This generation is performed according to packet size since distributions according to arrival time was partially implemented already. Our aim is to provide an in depth study regarding the performance of the various schedulers in the network and the effect various network parameters have on them. Since no real-network trace data is available, we resort to computer simulations. With Ns-2, we implement four different standardized perhop-behaviours (PHBs), namely expedited forwarding (EF), assured forwarding (AF1, AF2) and besteffort (BE). The evaluation focuses mainly on the EF PHB in regards to the other PHBs. The priority queuing (PQ), start-time fair queuing (SFQ), self-clocked fair queuing (SCFQ), weighted fair queuing (WFQ), worst-case weighted fair queuing plus (WF2Q+) and low latency queuing (LLQ) scheduling mechanisms are analysed to find their performance in relation to EF traffic and BE traffic. The QoS metrics that are focused on are: one-way delay (OWD), inter-packet delay variation (IPDV) and packet loss. We used Analysis of Variance (ANOVA) to analyse the impact of the various DiffSery node configuration parameters such as rates, packets sizes, schedulers and queue weights have on the output QoS metrics mentioned previously. Regression is then used to explain the relationship between several of these factors and metrics.

In search of higher speed and integration, the integrated circuit (IC) technology is scaling down. The total on-chip interconnect length is increasing exponentially. In fact, interconnect takes up the most part of the total chip area. The parasitics associated with these interconnect have significant impact on the circuit performance. Some of the effects of parasitics include cross talk, voltage drop and high current density. These issues can result in cross-talk induced functional failure and failures due to IR drop and electro-migration. This has resulted in interconnect- driven design trend in state-of-the-art integrated circuits. Reliability analysis, that includes simulating the effects of parasitics for voltage drop, current density, has become one of the most important steps in the VLSI design flow. Most of the CAD/EDA tools available, map these analysis results two dimensionally. Al- though this helps the designer, providing a three dimensional view of these results is highly desirable when dealing with complex circuits. In pursuit of visualizing reliability analysis results three dimensionally, as a first step, this work presents a tool that can visualize IC interconnect three di- mensionally. Throughout the course of this research open source tools were used to achieve the objective. In this work the circuit layout is stored as an OpenAc- cess database. A C++ program reads the design information using OpenAccess API and converts it to the .OBJ file format. Art of Illusion, an open source 3D modeling and rendering tool, reads this .OBJ file and models the IC interconnect three-dimensionally. In addition, Eclipse, an open source java IDE is used as a development platform. The tool presented has the capability to zoom in, zoom out and pan in real time.

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The electronic analog computer is widely used to simulate most types of automatic control systems, Only a limited amount of work has been reported, however, involving analog computer simulation of sampled-data systems, This is to be expected since such systems are essentially digital in nature. The purpose of the work described in this thesis was to develop methods of simulating various phenomena associated with sampled-data system, The techniques which have been developed are described ad evaluated in the report. In addition, experimental data is presented to illustrate the performance of the various simulation circuits. As an illustration of the techniques which have been developed, the simulation of a representative sampled-data system is described. Data obtained from this simulation is included in the report. / Master of Science