Physical processes which are governed by differential equations or difference equations with discontinuous behavior can be modeled as jump systems. An important type of jump systems is the one evolving linearly among the discrete events; this type of systems is called jump linear systems. A common analysis approach is to employ stochastic processes to describe the sequences, switches, and statistic properties of the discrete events. In this thesis, the jump linear systems to be studied are governed by semi-Markov processes. This type of jump linear systems is called the semi-Markov jump linear system. Due to the nature of the jump linear system, it finds many applications in networked control systems, fault tolerant control systems, and other systems subject to abrupt changes. It is worthwhile to mention that the well studied Markov jump linear system is a special case of the semi-Markov jump linear system. The thesis consists of two parts: The analysis and synthesis of semi-Markov jump linear systems and networked dynamic systems. In Chapter 2 and Chapter 3, the stochastic stability and optimal control for semi-Markov jump linear systems with or without time delays are investigated. In Chapter 4, a novel fault tolerant control scheme is proposed based on the semi-Markov jump linear system stability conditions. Chapter 5 to Chapter 7 discuss the networked dynamic systems analysis via jump linear system approaches. The stochastic stability conditions for semi-Markov jump linear systems are firstly derived. The Lyapunov theory is used to establish the sufficient stability conditions by deriving the infinitesimal generator of the Lyapunov function. Since in practice, almost all the system models could not be identified precisely, robust control problems for systems with uncertainties are investigated based on the established stability conditions. Considering the potential applications on networked systems where time delays are inevitable, optimal control problems for systems with time-varying delays have been studied. In the fault tolerant control design, the semi-Markov process is ideal to characterize time-varying failure rates of the system components whose life time is not exponentially distributed. The designed controller is capable of maintaining the stability when an actuator malfunctions. In the networked control system analysis, stochastic processes are used to model time delays and sensor scheduling rules. Network limitations are compensated by considering more historical information or planning for all possible delays that happen in the future. Both simulations and experiments show the improvements of the control performance by using the proposed techniques. A networked haptic system is investigated via the switching system approach. In the haptic system, the avatar interacts one-dimensionally with a multi-material virtual wall in the virtual environment.The random trajectory along which the avatar moves upon the wall is modeled by stochastic processes, then the multi-material virtual wall rendering is achieved. Finally, the thesis work is summarized and two future research topics are proposed. One is on the networked control system design where delays are modeled by semi-Markov processes, and the other one is on the event-trigger scheme design for networked dynamic systems. / Graduate / 0548 / 0544 / 0546 / jihuang@uvic.ca

Inter-organizational collaboration based on the use of IT systems is now essential for organizations working as Collaborative Networked Organizations (CNOs). However, little research has been done to examine the critical success factors involved in shared IT governance among members of a CNO. Accordingly, this research develops a model of inter-organizational IT-governance composed of critical success factors (CSFs) and key performance indicators. The study defines fourteen CSFs that are classified under the main four categories of IT governance, which include strategic alignment, resource management, value delivery and risk management, and performance measurement. In addition, the study identifies key performance indicators that measure the CSFs and evaluate the effectiveness of how partners work together in joint processes for a common goal. The main dimensions of the KPIs include consensus, alignment, accountability, trust, involvement and transparency. The model was validated by gathering feedback from participants in a healthcare on the importance of the CSFs and performance indicators. The findings confirm the importance of the CSFs but suggest that they could be ranked in order of criticality. In addition, certain CSFs were re-defined based on the experience of CNO participants and questions were raised related to the context of the CNO, which influences participant perceptions, as well as the degree of formalization noted in the CNO.

Management of Collaborative Networked Organizations faces various challenges in terms of decision-making. Particularly, in complex and multi-player environments, like healthcare, it is not easy to find the roots of low performance processes, and unmet goals. This research provides a framework, as well as associated techniques to analyze the value network, identify problematic actors, and consequently, find the best possible solution to change them. The proposed framework consists of two main components: Analyzing the value network, and Multi-Criteria Decision Making. To analyze the value network of a collaborative environment, in addition to the existing techniques, four complementary components are introduced: Actors’ value interchanges matrix, Value Gantt chart, Identifying problematic actors flowchart, and Actors’ ease of substitution table. Employing these hybrid analyses, decision makers gain a better understanding of the bottlenecks in the value network, current conditions and contributions of the involved actors, and the consequences of considering various alternatives. Then, by applying one of the Multi-Criteria Decision Making methods, and based on pre-defined criteria, possible alternatives are analyzed and outlined. As a proof of concept and validation of the proposed methods, we reviewed a scenario of patient flow and wait times in healthcare. We derive the value network for collaborative processes in a hospital, specify the roles’ of actors, identify the bottlenecks, then rank the solutions, and suggest possible changes to improve the performance of the collaborative environment.

Ethernet is a common practice to reconstruct a networked telemetry system. However, Ethernet switch cannot best meet the requirement of data transportation in a telemetry system because of its asynchronous mode and the uncertainty of latency time. In addition, the temporal order of the telemetry data will be disrupted when using an Ethernet switch. A device similar to Ethernet switch is presented in this paper, which can transport data synchronously without losing the original temporal order of the telemetry data. Meantime, a special condition is arranged by the device that the timing signal could be transmit from the device to the receiver in a certain delay time, so a timing mechanism derived from IEEE 1588 PTP protocol could be adopted for high accuracy of timing and synchronous sampling control.

The three-dimensional perovskites are known for their wide range of interesting properties including spectral tunability, charge carrier mobility, solution-based synthesis and many others. Such properties make them good candidates for photovoltaics and photodetectors. Low-dimensional perovskites, on the other hand, are good as light emitters due to the quantum confinement originating from their nanoparticle size. Another class of low-dimensional perovskites, also called low-dimensional-networked perovskites (L-DN), is recently reemerging. Those interesting materials combine the advantages of the nanocrystals and the stability of the bulk. For example, zero-dimensional-networked perovskite (0-DN), a special class of perovskites and the focus of this work, consists of building blocks of isolated lead-halide octahedra that could be synthesized into mm-size single crystal without losing their confinement. This thesis focuses on the synthesis and investigation of the optical properties of the 0-DN perovskites through experimental, theoretical and computational tools. The recent discovery of the retrograde solubility of the perovskites family (ABX3), the basis of the inverse temperature crystallization (ITC), inspired the reinvestigation of the low-dimensional-networked perovskites. The results of the optical characterization showed that the absorption and the corresponding PL spectra were successfully tuned to cover the visible spectrum from 410 nm for Cs4PbCl6, to 520 nm and 700 m for Cs4PbBr6 and Cs4PbI6, respectively. Interestingly, the exciton binding energies (Eb) of the 0-DNs were found to be in the order of few hundred meV(s), at least five times larger than their three-dimensional counterpart. Such high Eb is coupled with a few nanoseconds lifetime and ultimately yielded a high photoluminesce quantum yield (PLQY). In fact, the PLQY of Cs4PbBr6 powder showed a record of 45%, setting a new benchmark for solid-state luminescent perovskites. Computational methods were used to calculate the bandgap and study the corresponding excitonic behavior. However, the unexpected mismatch between the calculated and experimental bandgaps questions the origin of the high luminescence, which to date, remains an area of scientific debate that needs further study. Until then, the high PLQY, together with the spectral tunability, insensitivity to particle size and stability all offer a new avenue for more sustainability in light-emitting materials

This article-format dissertation focuses on how scholars use social media to support their scholarship. The first article is a scoping literature review that outlines current research. While overviewing an emergent field of literature, the article highlights motivations for using social media use, discusses benefits and drawbacks of this use for scholarship, explains how this discourse has evolved over time, and shares implications of what further topics can be investigated as well as implications for post-secondary institutions and scholars integrating social media use into their professional roles. In article two, I built a classifier and used it to analyze the Twitter data of those who self-identified as post-secondary scholars. The goal of the classifier was to analyze patterns of actual use rather than self-reported use. It was discovered that use is primarily personal, although many scholars use these to represent an aspect of their professional identity. The classifier was then tested on a sub-group of learning technology scholars to identify variance that may exist in the ways in which scholars of a singular field may be using Twitter. The third article was a phenomenological study that investigated the lived experiences of faculty using social media to support their scholarship. Through the study, five themes emerged as scholars discussed their use of Twitter and other social media and those were (a) positive relational impacts and community building, (b) using social media as a tool for open scholarship, (c) identity presentation, (d) the ethics of social media platforms, and (e) drivers for change over time. The study also found that although scholars may appear to be using social media for varied purposes, their Twitter profiles are often seen as primarily or completely a professional platform with which they engage with their communities and expand their definition of scholarship. The conclusion of the dissertation highlights findings across the three articles and provides directions for future research.

Tracking small unmanned aircraft systems (SUAS) becomes increasingly important with their increased use in populated areas. We propose an effective tracking solution for SUAS using a networked system of one-dimensional scanning radars. Tracking SUAS with a network of radar systems requires extrinsic calibration of each radar to a common frame. We provide a calibration solution using an orthogonal Procrustes formulation that associates radar measurements from the ground-mounted radar to real-time-kinematic Global Positioning System (RTK-GPS) data. Two variations of the calibration are presented, an online and batch processing method. Outdoor hardware experiments validate the capabilities of the radar network in tracking SUASs. The advantages and disadvantages of the two calibration methods are also illustrated with simulation and hardware tests.

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ITC/USA 2009 Conference Proceedings / The Forty-Fifth Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2009 / Riviera Hotel & Convention Center, Las Vegas, Nevada / It talks about a distributed net-based flight test raw data processing system, web-oriented and application oriented. The system likes a normal one, consists of database servers, web servers and NAS storage server, but with the particular distributed task scheduler servers and the calculation servers. Each type server can be a team. The user can use WEB browser with the help of OCX control to setup his own processing task according to his need, choose which plane, which flight no., and defining the parameters, flight time segments, extracting rate etc to be processed. The system can accomplish the processing using the embedded application middleware, various data processing modules in database, with the scheduler servers and processing servers. The system can meet many users' demand of huge quantity non-structural flight raw data quickly and efficient processing at the short time, ensure the flight data enhanced management, to keep from copying and distributing the great quantity raw data inefficiently and out-of-management.

ITC/USA 2008 Conference Proceedings / The Forty-Fourth Annual International Telemetering Conference and Technical Exhibition / October 27-30, 2008 / Town and Country Resort & Convention Center, San Diego, California / With the growing interest in networked data acquisition there has been a lot of focus on networked data acquisition systems. However, the requirements of a flight test instrumentation system go beyond networked DAU's. For example, a FTI network fabric has particular requirements for switches, time grandmasters, recorders, data servers and network terminals to the ground. This paper discusses these components and how they inter-operate in a single, fully networked system and discusses some FTI oriented requirements for same. Where relevant, we discuss the results of some experiments with network latencies; packet losses etc. and discuss some enhancements that can contribute to improved efficiency for flight test programs.