Recent impactful advances in integrated photonics undoubtedly owe much to silicon and its associated enabling platform (SOI). Although silicon has proved to be an indispensable element in many photonic systems yet it seems that it is not the ultimate solution to address all the challenges facing the photonics community. Therefore, integration of silicon with other optical materials featuring diverse properties is highly desirable. Such integration will be conducive to platforms which are naturally more capable and are suited for implementation of a wider range of optical devices and diverse functionalities. This dissertation is dedicated to design and implementation of integrated optical elements for hybrid material platforms. The basic theoretical foundation of integrated photonics is laid out in Chapter 2. In Chapter 3, an interlayer grating coupler for a specific hybrid material platform is designed, and demonstrated. Considering the fact that in almost all integrated photonic platforms, fabrication imperfections lead to an unpredictable shift in the wavelength of operation of individual devices, post fabrication tuning/trimming is inevitable. A number of widely used post fabrication trimming/tuning methods are briefly reviewed in Chapter 4 with special emphasis on a method based on electron beam exposure. In Chapter 5, an ultra-fast, low-power, and self-trimmable electro-optic modulator in demonstrated on a Si-based multilayer platform. Due to its remarkable optical and electronic properties, graphene has become a valuable material for opto-electronic applications. Integration of this novel 2D material with SOI platform is investigated in Chapter 6. Graphene-based electro-optic modulation through absorption and refractive-index change is successfully demonstrated using electrostatic gating mechanism. Chapter 7 is devoted to demonstration of a field-programmable 2 by 2 optical switch on a vertically stacked Si/SiO2/SOI platform. In Chapter 8, the peak-dragging phenomenon in a nanobeam photonic crystal cavity is studied. The optical bistability associated with this nonlinear phenomenon is of great interest for all-optical processing and sensing application. Future directions of this thesis are also discussed in the last Chapter.

There has been a move recently in academia, industry, and the consumer space towards the use of unsupervised parallel computation and distributed networks (i.e., networks of computing elements working together to achieve a global outcome with only local knowledge). To fully understand the types of problems that these systems are applied to regularly, a representative member of this group of unsupervised parallel and distributed systems is needed to allow the development of generalizable results. Although not the only potential candidate, the field of cellular automata is an excellent choice for analyzing how these systems work as it is one of the simplest members of this group in terms of design specification. The current ability of the field of cellular automata to represent the realm of unsupervised parallel and distributed systems is limited to only a subset of the possible systems, which leads to the main goal of this work of finding a method of allowing cellular automata to represent a much larger range of systems. To achieve this goal, a conceptual framework has been developed that allows the definition of interconnected systems of cellular automata that can represent most, if not all, unsupervised parallel and distributed systems. The framework introduces the concept of allowing the boundary conditions of a cellular automaton to be defined by a separately specified system, which can be any system that is capable of producing the information needed, including another cellular automaton. Using this interconnection concept, two forms of computational simplification are enabled: the deconstruction of a large system into smaller, modular pieces; and the construction of a large system built from a heterogeneous set of smaller pieces. This framework is formally defined using an interconnection graph, where edges signify the flow of information from one node to the next and the nodes are the various systems involved. A library has been designed which implements the interconnection graphs defined by the framework for a subset of the possible nodes, primarily to allow an exploration of the field of cellular automata as a potential representational member of unsupervised parallel and distributed systems. This library has been developed with a number of criteria in mind that will allow it to be instantiated on both hardware and software using an open and extendable architecture to enable interaction with external systems and future expansion to take into account novel research. This extendability is discussed in terms of combining the library with genetic algorithms to find an interconnected system that will satisfy a specific computational goal. There are also a number of novel components of the library that further enhance the capabilities of potential research, including methods for automatically building interconnection graphs from sets of cellular automata and the ability to skip over static regions of a given cellular automaton in an intelligent way to reduce computation time. With a particular set of cellular automaton parameters, the use of this feature reduced the computation time by 75%. As a demonstration of the usefulness of both the library and the framework that it implements, a hardware application has been developed which makes use of many of the novel aspects that have been introduced to produce an interactive art installation named 'Aurora'. This application has a number of design requirements that are directly achieved through the use of library components and framework definitions. These design requirements included a lack of centralized control or data storage, a need for visibly dynamic behaviour in the installation, and the desire for the visitors to the installation to be able to affect the visible movement of patterns across the surface of the piece. The success of the library in this application was heavily dependent on its instantiation on a mixture of hardware and software, as well as the ability to extend the library to suit particular needs and aspects of the specific application requirements. The main goal of this thesis research, finding a method that allows cellular automata to represent a much larger range of unsupervised parallel and distributed systems, has been partially achieved in the creation of a novel framework which defines the concept of interconnection, and the design of an interconnection graph using this concept. This allows the field of cellular automata, in combination with the framework, to be an excellent representational member of an extended set of unsupervised parallel and distributed systems when compared to the field alone. A library has been developed that satisfies a broad set of design criteria that allow it to be used in any future research built on the use of cellular automata as this representational member. A hardware application was successfully created that makes use of a number of novel aspects of both the framework and the library to demonstrate their applicability in a real world situation.

This work deals with a class of nonlinear dynamical systems exhibiting both continuous and discrete dynamics, which is called as hybrid dynamical system. We provide a broader framework of generalized hybrid dynamical systems allowing us to handle issues on modeling, stability and interconnections. Various sufficient stability conditions are proposed by extensions of direct Lyapunov method. We also explicitly show Lyapunov formulations of the nonlinear small-gain theorems for interconnected input-to-state stable hybrid dynamical systems. Applications on modeling and stability of hybrid dynamical systems are given by effective strategies of vaccination programs to control a spread of disease in epidemic systems. / Entwicklung eines Frameworks für hybride dynamische Systeme zur Decomkosition oder Komposition solcher Systeme. Untersuchung der Stabilität von gekoppelten hybriden Systemen.

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ITC/USA 2015 Conference Proceedings / The Fifty-First Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2015 / Bally's Hotel & Convention Center, Las Vegas, NV / In this work, a 3D-printable multilayer phased array system is designed to demonstrate the applicability of additive manufacturing technique combining dielectric and conductor processes at room temperature for RF systems. Phased array systems normally include feeding networks, antennas, and active components such as switches, phase shifters and amplifiers. To make the integrated system compact, the array system here uses multilayer structure that can fully utilize the 3D space. The vertical interconnections between layers are carefully designed to reduce the loss between layers. Simulated results show good impedance matching and high-directive scanning beam. This multilayer phased array will finally be 3D printed by integrating thermal / ultrasound wire mesh embedding method (for metal) and fused-deposition-modeling technique (for dielectric).

With the penetration of PV on the distribution system continually increasing, new advanced simulation methods are necessary to model the potential technical impacts of PV to the equipment and operation of the distribution system. With distributed PV, a timeseries analysis approach is necessary to more fully capture the time-varying nature of solar energy and the interaction with distribution system operations. The objective of the research is to streamline the PV interconnection process by providing more accurate methods that require less time for both the PV interconnection screening criteria and the PV interconnection impact study process. To improve the computational speed of timeseries simulations, an equivalent circuit reduction method is developed to simplify the circuit to a reduced-order model. The reduced circuit is equivalent during timeseries simulations, but it solves in a fraction of the time. The algorithm works with unbalanced multi-phase complex distribution system models, and it is shown to have high accuracy when validated against the full feeder models. An advanced PV hosting capacity simulation tool is developed and used to quantify system impacts for many PV interconnection scenarios, configurations, and locations, which can be generalized to develop improved future interconnection screening criteria. The advanced tools quantify location-specific impacts and the locational hosting capacity of potential PV interconnection locations on the feeder, including PV impact signatures and zones. A set of 50 different real distribution systems is analyzed in detail to demonstrate the range of scenarios and impacts that can occur depending on the feeder characteristics and topology. Specific methods are developed for time-series analysis, faster simulation times, distribution system equivalent circuit reduction, and PV hosting capacity analysis. The advancements presented in this thesis assist in streamlining PV interconnection studies with faster interconnection analysis times and more accurate screening criteria.

<p>In communication systems, the need for high bandwidth interconnects and</p><p>efficient distribution of large amount of data is very essential. This thesis work</p><p>addresses all-optical packet switching issues in the field of reconfigurable optical</p><p>interconnection networks for high performance embedded systems. The recent</p><p>research conducted at the Halmstad University, on high performance embedded</p><p>systems, focuses on the optical interconnection techniques to achieve ultra high</p><p>throughputs and reconfigurability at the system level.</p><p>Recent research in the field of optical interconnection networks for applications</p><p>like switches and routers for data and telecommunication industry and parallel</p><p>computing architectures for embedded signal processing use optical to electrical</p><p>conversion to switch packets. This conversion scales down the enormous bandwidth</p><p>capacity of the optical communication channels to electronic processing rates. To</p><p>maintain the high throughputs all over the interconnection networks, the optical</p><p>packets need to be maintained in optical state and switched to different part of the</p><p>interconnection network. To achieve this goal, all-optical packet switching</p><p>architectures are studied. The study is concluded with a positive outlook towards alloptical</p><p>switching technologies, and it will play a very important role in the near</p><p>future in the field of optical communication, telecommunication and embedded</p><p>systems.</p>

We present methods of calculating the value of two performance parameters for multipath, multistage interconnection networks: the normalized throughput and the probability of successful message transmission. We develop a set of exact equations for the loading probability mass functions of network channels and a program for solving them exactly. We also develop a Monte Carlo method for approxmiate solution of the equations, and show that the resulting approximation method will always calculate the values of the performance parameters more quickly than direct simulation.

In communication systems, the need for high bandwidth interconnects and efficient distribution of large amount of data is very essential. This thesis work addresses all-optical packet switching issues in the field of reconfigurable optical interconnection networks for high performance embedded systems. The recent research conducted at the Halmstad University, on high performance embedded systems, focuses on the optical interconnection techniques to achieve ultra high throughputs and reconfigurability at the system level. Recent research in the field of optical interconnection networks for applications like switches and routers for data and telecommunication industry and parallel computing architectures for embedded signal processing use optical to electrical conversion to switch packets. This conversion scales down the enormous bandwidth capacity of the optical communication channels to electronic processing rates. To maintain the high throughputs all over the interconnection networks, the optical packets need to be maintained in optical state and switched to different part of the interconnection network. To achieve this goal, all-optical packet switching architectures are studied. The study is concluded with a positive outlook towards alloptical switching technologies, and it will play a very important role in the near future in the field of optical communication, telecommunication and embedded systems.