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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
261

Leadership Influence on Aviation Safety Culture Inculcation as It Relates to Certified Non-Scheduled Air Taxi Operators

Birch, Stephen 23 June 2018 (has links)
<p> A general aviation industry segment member known as a Certified Non-scheduled Air Taxi Operator (CNATO) conducts passenger flights on-demand for hire. While airline accidents have reached historic lows, CNATO accident rates remain above one per 100,000 hours (NTSB, 2015b). Unlike airlines, the Federal Aviation Administration has not made safety management system implementation mandatory within CNATOs. As a result, there has been no decrease in CNATO organizational accidents over a 6-year period since 2009. Study goals strove to find a predictable method of variable identification influencing at-risk CNATOs. </p><p> The study utilized a sequential transformative design comprising quantitative surveys and aviation accident databases to answer four research questions. Research questions used explanatory correlational methodology of independent and intervening variables examining descriptive, relational, and comparative results. Safety Culture Indicator Scale Measurement System (SCISMS) and Multifactor Leadership Questionnaire (MLQ) Form 5x served as survey instruments that gathered leadership and safety culture information. Accident data was obtained from government sources through the Aviation Safety Information Analysis and Sharing (ASAIS) database. </p><p> An inclusion criterion, stratified random cluster, and systematic random sampling narrowed the entire 2,046 CNATO population to a sample size of 25 participants from three FAA flight standards regional offices. Each participant had 3-weeks to complete an online survey containing 106 questions. Twenty participants completed the survey. Data analysis followed a discriminant function analysis to develop quantitative correlations between multiple variables. Characteristics of each participant yielded no conclusive data to suggest CNATOs share common safety culture dimension dominance. Study results concluded there was no relationship between leadership style, safety culture dominance, and accident rates. A comparison of CNATOs using safety management systems and accident rates also showed no relationship exists. The final research question sought to find a relationship between leadership style, safety dimension, and accident rate. None was found, however, a statistical trend emerged outside the research questions as a result of sequential research design. Data indicated a relationship among transformational leadership characteristic scale and SCISMS mean score. While the study yielded seminal individual results, research questions proved safety culture remains difficult to define and found relationships to identify at-risk organizations remains elusive.</p><p>
262

Nontraditional Leadership Development Techniques of Nonprofit Aspiring Executives| An Exploratory-Interpretive Case Study

Ottah, Kan 07 June 2018 (has links)
<p> Leadership transition literature indicated that nonprofit sector current leaders lack understanding of proper ways to make use of relevant management leadership techniques to develop new leaders. New leaders replacing retiring organizational leaders lacked managerial experience and training needed to lead employees and manage organizational resources. The purpose of this study was to explore, understand, and interpret leadership supportive systems techniques that characterize &ldquo;Plan A,&rdquo; vision used for professional development of aspiring nonprofit executives for capacity building of critical leadership skills and management of networking functions toward organizational sustainability. The conceptual framework of this study focused on supportive systems leadership development theory, nontraditional leadership development theory, and &ldquo;Plan A&rdquo; leadership development theory. The study adopted qualitative exploratory-interpretive case study to generate research data through surveys, document analyses, interviews, and focus group discussions for research questions 1 and 2. Data generated were analyzed using embedded thematic data analysis strategy and qualitative NVivo 11 software. The major integrated themes that emerged characterizing the unique features of &ldquo;Plan A&rdquo; vision of nontraditional leadership development techniques were: (a) vision and leadership empowerment, (b) performance and feedback, (c) efficiency and conflict management, and (d) effective communication between leaders and aspiring executives in the workplace. The study contributed to nonprofit leadership transition by interpreting and providing in-depth understanding of leadership development roles that involved leadership development persuasion, collaboration, consultation, and encouragement for aspiring executives to seek leadership roles within the nonprofit management team. </p><p>
263

Development of Unintended Radiated Emissions (URE) Threat Identification System

Friedel, Joseph E. 26 April 2018 (has links)
<p> There&rsquo;s always a requirement for faster, more accurate, and easier to implement threat identification systems for concealed electronics, to thwart terrorism and espionage attempts. Common electronic devices are used in the design of improvised explosive devices (IEDs) that target military and civilian populations alike, while concealed recording devices illegally capture proprietary and confidential data, compromising both governmental and industrial information resources. This research proposes a unique nonintrusive, repeatable, reliable and scalable D&amp;I system for identifying threat devices by unintended radiated emissions (URE). Only a passive URE system, as opposed to active or hybrid systems, is appropriate for bomb detection or human interrogation, since potentially hazardous energy radiations are not emitted. Additionally, the proposed system is distinctive in its simplicity, allowing rapid implementation, and easy expandability. Finally, validation testing is provided to demonstrate the system&rsquo;s reliability and repeatability. </p><p> URE is the electromagnetic emissions that active electronic equipment, such as radios and cellphones radiate. URE is analogous to a human fingerprint, since on a microscopic level, each and every URE signature is unique. However same-type electronic devices put out similar radiations and electronics of the same model have almost identical radio frequency signatures. URE signatures can change with device settings, such as a channel on a radio, or Airplane versus Clock mode on a cell phone. This uniqueness of URE data per device setting enables URE to be used to determine the mode of an operational electronic device. The characteristics of URE enable it to be used for explosive ordinance detection (EOD) and applications such as quality control in manufacturing, electronics troubleshooting,device identification for inventory, and detection of prohibited hidden electronics. </p><p> The proposed D&amp;I process also addresses big data problems involved in capturing URE data and building a database of URE characteristics for identification. Issue interpretation is utilized with the URE data to distinguish between threat and non-threat electronic devices, using multiple criteria decision analysis (MCDA) and decision-making techniques to determine type, model and mode of the hidden devices. The outlined URE data handling methods and specified decision analysis techniques for URE data processing are further unique contributions of this research. </p><p> Optimization, verified by testing, is used to improve the speed and accuracy of the identification decision algorithm. The developed system is validated with URE data from 166 devices, which are representative of IED and espionage threats, but the system is extendable to all URE D&amp;I applications, such as Quality Assurance, Inventory, and smart applications. Due to the immaturity of the URE D&amp;I field and lack of documentation on the topic, the properties and potential of this more effective D&amp;I system, compared to current methods, will be of interest to explosive ordnance disposal, security service, electronic system manufacturing, automated inventory, and mobile application development communities and potentially others as well. </p><p>
264

Complex socio-technical system disasters, crises, crimes, and tragedies| A study of cause from a systemic wholeness perspective

Toth, William J. 18 March 2017 (has links)
<p> Researchers and practitioners continue to study the causes of high consequence failures in complex socio-technical systems. Often linear causal pathways are identified in investigations that blame individual human error, or technical malfunctions. This study represents a significant expansion in the analysis of high profile accidents, crimes, crises, and tragedies to accommodate system complexity. Presented is a model of socio-technical system wholeness that provides an integral framework with which socio-technical system deficiencies are analyzed. The research questions if lack of systemic wholeness is the cause for selected high profile events.</p><p> This case study used historical documents pertaining to 13 actual events that included espionage, high consequence accidents, mass killings, and the response to natural disasters. The documentation included government commission reports and previously recorded interviews. A hermeneutic analysis method guided the iterative development of deficiency codes. These codes were assigned to key statements in the documentation that described the varied deficiencies. The qualitative analysis software, Atlas.ti aided in the coding of approximately 5,000 of pages of documentation. Deficiency codes were then organized and the highest frequency codes are listed and are also shown graphically on the integral model, to reveal characteristic patterns.</p><p> In all of the cases, significant deficiencies are shown in all dimensions of the integral wholeness model. Deficiencies are described as systemic holes and shadow aspects. Holes and shadow aspects form patterns within and among cases, spanning the various subject areas. Systemic boundaries pertaining to each case are also described using the wholeness model. In several of the cases, multiple systems are shown with systemic links. Deficiencies in the links were also identified from the data and are presented.</p><p> The dynamic process of movement towards socio-technical systems wholeness is perpetual. It is also essential when the consequence of socio-technical systems failure threatens individuals, communities or the natural environment. The research shows the need for constant vigilance and attention to holes in protective defenses, and reconciliation with shadow aspects to avert systemic failure. This research has a broad span. Additional research opportunities include using this wholeness model for in-depth analysis of single socio-technical system prior to failure</p>
265

Liquid Systems for Carbon Dioxide Removal in Spacecraft Environments

Paragano, Matthew Vincent 11 April 2018 (has links)
<p> As humans strive to explore deeper into the solar system, the need for efficient, compact, and reliable life support systems for providing breathable air and drinkable water become critical to mission success. One element of providing breathable air is the removal of metabolic gaseous waste products, primarily consisting of carbon dioxide, from the cabin air. Recent work on human performance has suggested that carbon dioxide has effects on human performance at lower concentrations than previously anticipated and at concentrations lower than presently controlled to on the International Space Station. Such performance requirements represent a substantial challenge and provide the opportunity for an alternative solution to the zeolites presently in use. The present work examines the feasibility of using liquid a bsorbents to perform carbon dioxide absorption in enclosed microgravity environments.</p><p> The use of liquid absorbents for carbon dioxide removal (or capture) is well studied in literature. Chief among the absorbents studied is monoethanolamine, an organic base which reacts to neutralize carbon dioxide. The reactivity of bases with amines increases the mass transfer rate, a particularly desirable feature for systems requiring compact architectures. To improve the diffusivity of carbon dioxide and reaction products, amines are typically dissolved in water, which has a low viscosity and solubilizes amines well. However, as analyzed in this work, aqueous sorbents are unattractive in enclosed environments because the water will evaporate into the cabin. As an alternative, an off-the-shelf, non-aqueous mixture of aminoethylethyleneamine and triethylene glycol was developed which shows moderate viscosity characteristics with low-volatility components and full miscibility.</p><p> This work investigates for the first time the use of electrospray as a nanoscalegas -liquid contactor to improve the mass transfer while using a viscous liquid absorbent. Experimental investigation of this phenomenon concludes that electrospray shows a high overall mass transfer rate at all loadings than a stationary film. The proposed reason for the continued high mass transfer rate is the continuous refreshing of the gas-liquid interface with unreacted amine. Varying parameters for the concentrations of carbon dioxide and a mine, the liquid flow rate, and the driving electricfield show the data may be collapsed by an empirical dimensionless group which relates to the liquid pool at the bottom of the spray that represents a well-mixed interface. In addition, the influence of carbon dioxide reacting with the surface of the electrospray cone was studied experimentally with monoethanolamine, concluding that emitted current increases with carbon dioxide partial pressure due to production of ionic reaction products changing electrical conductivity. </p><p> Finally, the mass transfer of water vapor and carbon dioxide through a microporous polytetrafluoroethylene membrane into aqueous and non-aqueous aminoethylethanola mine solutions. Aqueous solutions show water vapor losses, consistent with expectations, which would impose a condensation risk to cabin environments.</p><p>
266

Adaptive control and learning using multiple models

Wang, Yu 11 April 2018 (has links)
<p> Adaptation can have different objectives. Compared to a learning behavior, which is mainly to optimize the rewards/experience obtained through the learning process, adaptive control is a type of adaptation that follows a specific target guided by a controller. Although the targets may be different, the two types of adaption share common research interests.</p><p> One of the popular research techniques for studying adaptation is the use of multiple models, where the system will utilize information from multiple environment observers instead of one to improve the adaptation behavior in terms of stability, speed and accuracy. In this thesis, applications of multiple models for two types of adaptation, adaptive control and learning, will be investigated separately. For adaptive control, the research focuses on second-level adaptation, which is a new multiple-model-based approach; for learning, the multiple model concept is designed and embedded into a type of reinforcement scheme: learning automata.</p><p> The stability, robustness and performance of second-level adaptation will be first investigated in the context of various environments, including time-varying plants and noisy disturbances. Then, a new design of second-level adaptation for general systems and input-output accessible systems will be discussed. The reasons for the improved performance using second-level adaptation are analyzed theoretically. The second part of the thesis contributes to a new method of learning automata using multiple models. The method is first applied to a two-state (binary) reward environment in the simplest case, and it is later extended to the feed-forward case when multiple states or actions are presented. Finally, general reinforcement learning automata for network cases will be discussed. In all cases, simulation studies are given, wherever appropriate, to demonstrate the improvement in performance compared to conventional approaches.</p><p>
267

Finding Erich Jantsch's Five Crucial Innovations| A Study of Four Small Colleges

MacVie, Leah 13 October 2017 (has links)
<p> Institutions of higher education have faced many challenges over the last few decades. Though many large institutions have the resources needed to respond to these challenges, small institutions have had to be innovative in the ways in which they are adapting. There are similarities between the external challenges that institutions face today and the challenges they faced in the 1960s and 70s, and it is worth examining whether or not the predictions and suggestions made by scholars in this time period offer insight in regards to the innovation found in small institutions today. This dissertation explored Erich Jantsch's 1969 report in the context of innovation in higher education today. This qualitative, multicase study found that Erich Jantsch's five crucial innovations can be found to some extent in the innovations of four small institutions of higher education.</p><p> Keywords: Erich Jantsch, higher education, disruptive forces, innovation, self-renewal, integrative planning</p><p>
268

A Multimodal Study on How Embodiment Relates to Perception of Complexity

Polk, Robert B. 14 September 2017 (has links)
<p> This preamble study asks whether amplifying our embodied knowing may heighten our ability to sense the complex adaptive patterns in our daily lives. Embodied cognitivists argue nothing that qualifies as thinking was not itself first borne of our physical engagement with the natural world. In this stance, all knowledge is seen as corporeal in nature and thus generated from our intersubjective relationships with the world about us. As such, embodied perception is believed to be direct, veridical, and unmediated by the brain alone. This study also reinforces a growing consensus that the dominant locus for perceiving complex adaptive patterns is achieved through nonconscious rather than conscious processes. Consequently, this research marries the literatures of embodied cognition, nonconscious perception, and complexity to generate an original investigation into how manipulating these relationships could improve our abilities to access, sift through, and act more wisely in the patterns that matter the most. While attempts to establish a clear empirical connection amongst these phenomena were less than conclusive, this inaugural study also makes useful contributions in (a) reframing the array of literature around embodiment into a single, monist conception called the Mind, Body, Environment (MBE) Continuum; (b) lessons learned designing macro-level empirical research into nonconscious embodied perception; (c) providing an inaugural dataset upon which to build future inquiry into this domain, and finally (d) augmenting and testing a non-traditional research methodology called distributed ethnography commensurate to the unique nature of this inquiry.</p><p>
269

Model-Based Systems Engineering Application to Analyze the Ground Vehicle and Robotics Sustainment Support Strategy

Patria, Garett Scott 20 July 2017 (has links)
<p> Model-Based Systems Engineering and Logistics Engineering are emerging disciplines that offer a synergy for integrating the proactive modeling of prototype R&amp;D acquisition and industrial base sustainment support into a framework that characterizes the most influential phases of the Department of Defense ground vehicle and robotics equipment life cycle. This research enhances situational awareness of upstream factors that drive the capability and capacity constraints to leveraging new technology for sustainment risk mitigation. These capability and capacity constraints include sub-optimal supply chain coordination and limited collaboration between government R&amp;D centers. This research also demonstrates how a new business model called the Defense Mobility Enterprise solves these problems, while offering an incubator for Model-Based Systems Engineering experimentation and continuous productivity improvement. Through the successful application of SysML, the modeling language of systems engineering, this research concludes with multi-model orchestration, using the momentum of commercial-off-the-shelf tools, providing a strategic lens with which to specify, analyze, design, and verify Department of Defense ground vehicle and robotics technology transition opportunities.</p><p>
270

An Investigation of Circumstances Affecting Consumer Behavioral Intentions to Use Telemedicine Technology| An Interpretative Phenomenological Study

Cutts, Haywood 16 November 2017 (has links)
<p> Concerns related to the protection of personal identification information, graphic user interface, patient privacy, and consumer acceptance, to name a few, have plagued the implementation of telemedicine. Advocates of telemedicine have gained the interests of consumers but failed to recognize the true nature of consumer attitudes towards the use of telemedicine. This research was a significant step towards understanding consumer unwillingness to use telemedicine. Understanding and acknowledging what customers feel is detrimental to improving the telemedicine implementation process. The purpose of this qualitative study was to explore consumers who may have experienced cognitive dissonance between their interest and the use of wireless body area networks. The interpretative phenomenological method was employed to understand and contribute knowledge about the phenomenon. The research participants were randomly selected patients, physicians, nurses, paramedics, and healthcare professionals. The findings contribute to knowledge by exposing the relevance of understanding cognitive dissonance, and its underrated affiliations. Such alliances play a meaningful role when embracing or rejecting the use of telemedicine. Future research may consider aligning and employing use behavioral models, such as the social cognitive theory, or the social capital theory, to help increase knowledge and understanding of consumer cognitive dissonance towards the use of telemedicine Advocates planning to implement telemedicine in rural areas could use these findings to help diminish or subdue indigenous consumer anxiety towards the use of telemedicine.</p><p>

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