This dissertation comprehensively studies diverse cooperative and noncooperative amplify-and-forward (AF) multiple-input multiple-output (MIMO) wireless relay networks. Various gain matrices and vectors, such as relay amplifying matrices and beamforming vectors, are determined by using diverse criterions, such as minimum mean square error (MMSE), maximum signal-to-noise ratio (SNR), zero-forcing (ZF), and achievable rate (AR). In addition, multiple power constraints are considered in the optimization problems during data transmission. Moreover, both certain and uncertain channel state information (CSI) are considered as well. In particular, both one- and two-way AF MIMO relay networks are studied. Furthermore, by adopting the derived optimum gain matrices and vectors, cost functions (CFs), total transmitted relay power, total signal component power (SCP) at the destinations, ARs, and equalizers at the destinations are compared to each other for different cases. In particular, the minimization MSE CF criterion for the efficient relay selection scheme is proposed in this dissertation. This work also shows the relationship between the mutual information (MI) in nats and the MMSE with unit power of the transmitted signal for one- and two-way AF relay networks. Finally, this dissertation verifies the analytical results through MMSE, bit error rate (BER), and AR simulations of both optimum one-way and two-way distributed AF wireless relay networks. / Thesis (Ph.D.)-- Wichita State University, College of Engineering, Dept. of Electrical Engineering and Computer Science

Noroviruses are the most common cause of acute gastroenteritis in the US and worldwide, accounting for ~21 million cases of gastroenteritis annually in the US alone. Noroviruses are very stable in the environment and refractory to many common disinfectants, with only a few viral particles required to initiate virus infection. Therefore, norovirus outbreaks are hard to contain using routine sanitation, and even implementation of aggressive sanitary measures often fails to prevent subsequent norovirus outbreaks. Norovirus infection is a serious public health problem and underscores the importance of developing small molecule anti-norovirus therapeutics and prophylactics. However, there are currently no approved drugs or vaccines available for the treatment of norovirus infection. Norovirus 3CL protease is a druggable target that is well-suited to the discovery and development of anti-norovirus therapeutics and prophylactics. This dissertation describes the design, synthesis, and biochemical evaluation of the first series of inhibitors of norovirus 3CL protease. The identified hits were optimized using structure-based drug design approaches, to generate lead compounds with high pharmacological activity, selectivity, and drug-like characteristics. / Thesis (Ph.D.)-- Wichita State University, Fairmount College of Liberal Arts and Sciences, Dept. of Chemistry

Increasing attention paid to the high school dropout situation since the passage of No Child Left Behind (NCLB) (2000) has brought about concerns (United States Department of Education, 2002a). In an attempt to bring greater clarity to the complicated issues surrounding school dropouts, I explored several under-researched aspects relating to dropping out of high school, such as adults returning to a high school diploma program and the non-monetary benefits of obtaining a high school diploma. According to Harris and Ganzglass (2008), 39% of adult learners across the nation voluntarily return to an adult alternative program to work on their regular high school diploma. Of these adult students who return, why are only 30% actually completing the program? This study employed a qualitative interpretivist research design to attain an understanding of why adults dropped out of a virtual high school diploma program a second time. I conducted semi-structured interviews with 10 adults who had dropped out of high school for a second time, which provided these participants a voice, free to share his or her thoughts and feelings about past social exchanges through his or her own words. It became clear as a result of my data that no single reason fully explained why a particular study participant chose to drop out. Rather, one or more reasons occurred in tandem and it was this confluence of factors that created a sufficiently compelling set of circumstances that prompted each participant to exit the program. Implications from the research stress that additional research could be conducted in the areas of student connectedness, staff and administrators perceptions of why they feel certain students are not being successful in their school, and wraparound services for at-risk students and their families. / Thesis (Ed.D.)-- Wichita State University, College of Education, Dept. of Counseling, Educational Leadership, Education and School Psychology

An Ehresmann connection on a fiber bundle pi: E --> M is defined by prescribing a suitable horizontal subbundle H of the tangent bundle piT: TE --> E. For a horizontal bundle to be suitable, it must have a property called horizontal path lifting. This property ensures that the horizontal bundle determines a system of parallel transport between the fibers of E. The main result of this dissertation is a geometric characterization of the horizontal bundles on E that have horizontal path lifting, and hence are connections. In particular, it is shown that a horizontal bundle has horizontal path lifting if and only if its horizontal spaces are bounded away from the vertical spaces, uniformly along fibers of E. In order for a horizontal bundle to admit a system of parallel transport or have holonomy, it must be a connection. However, certain other geometric properties that are usually attributed to connections are actually properties of arbitrary horizontal bundles. These properties are studied in the case when E is either a vector bundle or tangent bundle, accordingly. / Thesis (Ph.D.)-- Wichita State University, Fairmount College of Liberal Arts and Sciences, Dept. of Mathematics, Statistics, and Physics

This dissertation consists of four published or accepted journal articles that address some of the key problems in prognostics and health management area (PHM). Effective health diagnostics and prognostics provide multifarious benefits such as improved safety, improved reliability and reduced costs for operation and maintenance (O&M) of complex engineered systems. Extensive literature reviews on PHM for diagnostics of system health conditions and O&M decision-making for complex engineered systems have identified important challenge problems for this dissertation as follows: - Effective diagnostics of current health states based on heterogeneous sensory data from multiple sensors is an intricate problem for condition monitoring techniques to be applied on complex engineered systems, mainly due to high system complexity and sensory data heterogeneity; - With an increasing system complexity, it is extraordinarily difficult to have a well-tested system so that all potential faulty states can be realized and studied at product testing stage. Thus, real time health diagnostics requires automatic detection of unexampled system faulty states based upon sensory data to avoid sudden catastrophic system failures; - Despite successful applications of different diagnostic algorithms in various engineering fields, a challenge for health diagnostics is that an implicit relationship between different system health states and features of sensory signals makes it difficult to develop a generally applicable health diagnostics technique. - Although diagnostics and prognostics can provide valuable information for proactive actions in preventing system failures, their benefits have not been fully utilized for the O&M decision-making process. To carefully address these important research problems, this dissertation proposes four research solutions: a multi-sensor health diagnostics technique using deep belief network, a tri-fold hybrid classification approach for diagnostics with unexampled faulty states, a multi-attribute classification fusion technique to develop a generally applicable health diagnostics framework and a generic prognostics-informed O&M decision-making framework by utilizing failure prediction information in the O&M decision-making process. In this dissertation, different practical engineering applications will be employed as case studies to demonstrate the efficacy of proposed research solutions. / Thesis (Ph.D.)-- Wichita State University, College of Engineering, Dept. of Industrial and Manufacturing Engineering

Community-based mental health services such as consumer-run organizations (CROs) have been shown to yield positive community integration outcomes for individuals who actively participate in these services. However, CROs have been historically underutilized despite having a growing evidence base that supports the financial and programmatic effectiveness of these consumer-driven services. Little is known about the organizational, social, and psychological factors that help engage mental health consumers in these organizations. The current study used the activity setting framework to conduct a comprehensive analysis of the organizational resources and peer support processes that impact members' sense of community and organizational participation in CROs. Interviews, setting observations, and survey methods were used to collect data on 16 CROs located across the state. Descriptive, correlational, and stepwise regression analyses were conducted to identify key characteristics that positively impact member outcomes. The activity setting framework provided a comprehensive lens for which to assess CROs. Results showed that organizational climate had the strongest impact on sense of community, while member characteristics (e.g., length of CRO membership and frequency of attendance) had stronger influences on organizational participation. CRO responsiveness was also a predictor of both sense of community and organizational participation. Suggestions are provided to help improve CRO practices and maximize member benefits from participation in these organizations. / Thesis (Ph.D.)-- Wichita State University, Fairmount College of Liberal Arts and Sciences, Dept. of Psychology

Undoubtedly, public schools in the United States have made tremendous progress over the last four decades in providing an equitable education for students with disabilities. Prior to the passage of federal law in 1975, many "handicapped" children were either denied access to schooling altogether, or received inadequate educational services in a segregated setting. Today, over six million students with disabilities attend regular schools alongside their abled peers. However, some minority students with disabilities, including African American, Native American, and Hispanic students, continue to receive segregated, inequitable educational services at rates significantly higher than other groups. This study examines the perceptions minority students with disabilities have about their access to equitable educational services. The framework supporting this study emanates from a critical tradition. A critical perspective uses critique as the primary means to identify the marginalization of nondominant groups. When students are given a voice, they are able to challenge assumptions and stereotypes held by adults, and they become empowered to resist marginalization. For this study, I interviewed four minority students with disabilities, and used the constant comparative method to analyze the participants' perceptions about their educational experiences. Implications from the research stress the need to give minority students with disabilities a greater voice in their educational services. Providing for student voice is the first step in ensuring equitable educational experiences for minority students with disabilities (National Education Association 2007). / Thesis (Ed.D.)-- Wichita State University, College of Education, Dept. of Counseling, Educational Leadership, Education and School Psychology

Physical destruction of a school and loss of material resources in a natural disaster are potentially traumatic experiences for students and school personnel (Ainsworth & Parkes, 1991). As a result of such destruction, emotional bonds to objects, people, places, and routines are frequently interrupted. When disaster occurs and students cannot immediately return to the pre-disaster learning environment, their academic progress may be compromised. Disaster relief efforts may be largely focused on physiological needs and the replacement of material goods, food, and clothing. There may be minimal focus on the psychological needs of those affected. Students who demonstrate symptoms of mal-coping may be at risk of academic underachievement and not graduating from high school (Cook-Cottone, 2004). This study uses narrative inquiry to investigate the education recovery of teachers, administrators, and students in a rural Midwestern town seven years after an EF5 tornado destroyed the schools and much of the community. The stories of their educational recoveries are examined through the theoretical lens of place attachment theory. Findings indicated a strong need for students to be reconnected with peers as soon as possible and for school staff members to reestablish daily routines. Recreating the physical environments in which social interactions occurred was instrumental to healing the psychosocial trauma of loss and displacement experienced by students and staff. The storytellers in this narrative highlighted the processes that were critical to making complete education recoveries. / Thesis (Ed.D.)-- Wichita State University, College of Education, Dept. of Counseling, Educational Leadership, Education and School Psychology

Multipath frequency-selective fading can degrade the performance of a wireless communication system significantly as the data rate increases, e.g., when the data rate is as high as those of systems beyond long-term evolution (LTE)-Advanced. An effective method to combat multipath fading is a code division multiple access (CDMA) scheme. The objective of this dissertation is to present an effective method in designing nonbinary, secure, and optimum spreading and despreading pseudo noise (PN) sequences for CDMA multi-relay networks under frequency-selective fading by employing a maximum signal-to-interference-plus-noise ratio (SINR) criterion. This dissertation assumes that channel state information (CSI) is known at a central station such as a cloud radio access network (CRAN), which computes the optimum PN sequences and forwards them to both sources and destinations. This dissertation considers both partially and fully connected relay networks consisting of multiple sources, multiple relays, and multiple destinations. Direct links from sources to destinations are available in fully connected relay networks, whereas they are not available in partially connected relay networks. This dissertation also finds the optimum PN spreading and despreading sequences jointly and iteratively using the proposed novel method for multiple sources and destinations. Furthermore, it examines the sensitivity of the proposed schemes to imperfect CSI and wideband jamming. Simulation results verify that the proposed method can effectively improve system performance and can converge much faster in finding optimum PN sequences jointly for multiple sources and destinations than existing schemes under the same environment. / Thesis (Ph.D.)-- Wichita State University, College of Engineering, Dept. of Electrical Engineering and Computer Science

Univ., Diss.--Louvain-la-Neuve, 2007.