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Biomass-Derived Activated Carbon through Self-Activation Process
Self-activation is a process that takes advantage of the gases emitted from the pyrolysis process of biomass to activate the converted carbon. The pyrolytic gases from the biomass contain CO2 and H2O, which can be used as activating agents. As two common methods, both of physical activation using CO2 and chemical activation using ZnCl2 introduce additional gas (CO2) or chemical (ZnCl2), in which the CO2 emission from the activation process or the zinc compound removal by acid from the follow-up process will cause environmental concerns. In comparison with these conventional activation processes, the self-activation process could avoid the cost of activating agents and is more environmentally friendly, since the exhaust gases (CO and H2) can be used as fuel or feedstock for the further synthesis in methanol production. In this research, many types of biomass were successfully converted into activated carbon through the self-activation process. An activation model was developed to describe the changes of specific surface area and pore volume during the activation. The relationships between the activating temperature, dwelling time, yield, specific surface area, and specific pore volume were detailed investigated. The highest specific surface area and pore volume of the biomass-derived activated carbon through the self-activation process were up to 2738 m2 g-1 and 2.209 cm3 g-1, respectively. Moreover, the applications of the activated carbons from the self-activation process have been studied, including lithium-ion battery (LIB) manufacturing, water cleaning, oil absorption, and electromagnetic interference (EMI) shielding.
Hungering for Independence: The Relationship between Food and Morale in the Continental Army, 1775-1783
An adequate supply of the right kinds of foods is critical to an army's success on the march and on the battlefield. Good food supplies and a dire lack of provisions have profound effects on the regulation, confidence, esprit de corps, and physical state of an army. The American War of Independence (1775-1783) provides a challenging case study of this principle. The relationship between food and troop morale has been previously discussed as just one of many factors that contributed to the success of the Continental Army, but has not been fully explored as a single issue in its own right. I argue that despite the failures of three provisioning system adopted by the Continental Congress - the Commissariat, the state system of specific supplies, and the contract system - the army did keep up its morale and achieve the victory that resulted in independence from Great Britain. The evidence reveals that despite the poor provisioning, the American army was fed in the field for eight years thanks largely to its ability to forage for its food. This foraging system, if it can be called a system, was adequate to sustain morale and perseverance.
Design of New Monodentate Ligands for Regioselectivity and Enantioselectivity Tuning in Late Transition Metal Catalysis
The ability of gold(I) to activate many types of unsaturated bonds toward nucleophilic attack was not widely recognized until the early 2000s. One major challenge in gold catalysis is the control over regioselectivity when there are two or more possible products as a result of complicated mechanistic pathways. It is well know that the choice of ligand can have dramatic effects on which pathway is being followed but very rarely are the reasons for this selectivity understood. The synthesis of new acyclic diaminocarbenes was developed and a study of the ligand effects on the regioselectivity of a gold-catalyzed domino enyne cyclization hydroarylation reaction and a Nazarov cyclization was undertaken. New chiral acyclic diaminocarbenes were also developed and tested along side new C3-symmetric phosphite ligands in an asymmetric intramolecular hydroamination of allenes. Structure activity correlations were developed for the potential use in further rational ligand design. The synthesis of 6a,7-dihydro-5-amino-dibenzo[c,g]chromene derivatives via a gold-catalyzed domino reaction of alkynylbenzaldehydes in the presence of secondary amines was developed. These were sent to be screened for biological activity.
Electrodeposited Metal Matrix Composites for Enhanced Corrosion Protection and Mechanical Properties
In the oil and gas industry, high corrosion resistance and hardness are needed to extend the lifetime of the coatings due to exposure to high stress and salt environments. Electrodeposition has become a favorable technique in synthesizing coatings because of low cost, convenience, and the ability to work at low temperatures. Electrodeposition of metal matrix composites has become popular for enhanced corrosion resistance and hardness in the oil and gas industry because of the major problems that persist with corrosion. Two major alloys of copper-nickel, 90-10 and 70-30, were evaluated for microbial corrosion protection in marine environments on a stainless steel substrate. Copper and copper alloys are commonly used in marine environments to resist biofouling of materials by inhibiting microbial growth. Literature surveying the electrodeposition of Cu-Ni incorporated with nano- to micro- particles to produce metal matrix composites has been reviewed. Also, a novel flow cell design for the enhanced deposition of metal matrix composites was examined to obtain the optimal oriented structure of the layered silicates in the metal matrix. With the addition of montmorillonite into the Ni and Cu-Ni matrix, an increase in strength, adhesion, wear and fracture toughness of the coating occurs, which leads to an increase corrosion resistance and longevity of the coating. These coatings were evaluated for composition and corrosion using many different types of instrumental and electrochemical techniques. The overall corrosion resistance and mechanical properties were improved with the composite films in comparison to the pure metals, which proves to be advantageous for many economic sectors including the oil and gas industry.
Fatigue Behavior of A356 Aluminum Alloy
Metal fatigue is a recurring problem for metallurgists and materials engineers, especially in structural applications. It has been responsible for many disastrous accidents and tragedies in history. Understanding the micro-mechanisms during cyclic deformation and combating fatigue failure has remained a grand challenge. Environmental effects, like temperature or a corrosive medium, further worsen and complicate the problem. Ultimate design against fatigue must come from a materials perspective with a fundamental understanding of the interaction of microstructural features with dislocations, under the influence of stress, temperature, and other factors. This research endeavors to contribute to the current understanding of the fatigue failure mechanisms. Cast aluminum alloys are susceptible to fatigue failure due to the presence of defects in the microstructure like casting porosities, non-metallic inclusions, non-uniform distribution of secondary phases, etc. Friction stir processing (FSP), an emerging solid state processing technique, is an effective tool to refine and homogenize the cast microstructure of an alloy. In this work, the effect of FSP on the microstructure of an A356 cast aluminum alloy, and the resulting effect on its tensile and fatigue behavior have been studied. The main focus is on crack initiation and propagation mechanisms, and how stage I and stage II cracks interact with the different microstructural features. Three unique microstructural conditions have been tested for fatigue performance at room temperature, 150 °C and 200 °C. Detailed fractography has been performed using optical microscopy, scanning electron microscopy (SEM) and electron back scattered diffraction (EBSD). These tools have also been utilized to characterize microstructural aspects like grain size, eutectic silicon particle size and distribution. Cyclic deformation at low temperatures is very sensitive to the microstructural distribution in this alloy. The findings from the room temperature fatigue tests highlight the important role played by persistent slip bands (PSBs) in fatigue crack initiation. At room ...
Highly Stretchable Miniature Strain Sensor for Large Dynamic Strain Measurement
This thesis aims to develop a new type of highly stretchable strain sensor to measure large deformation of a specimen subjected to dynamic loading. The sensor was based on the piezo-resistive response of carbon nanotube(CNT)/polydimethysiloxane (PDMS) composites thin films, some nickel particles were added into the sensor composite to improve the sensor performance. The piezo-resistive response of CNT composite gives high frequency response in strain measurement, while the ultra-soft PDMS matrix provides high flexibility and ductility for large strain measuring large strain (up to 26%) with an excellent linearity and a fast frequency response under quasi-static test, the delay time for high strain rate test is just 30 μs. This stretchable strain sensor is also able to exhibit much higher sensitivities, with a gauge factor of as high as 80, than conventional foil strain gauges.
Decision Makers’ Cognitive Biases in Operations Management: An Experimental Study
Behavioral operations management (BOM) has gained popularity in the last two decades. The main theme in this new stream of research is to include the human behavior in Operations Management (OM) models to increase the effectiveness of such models. BOM is classified into 4 areas: cognitive psychology, social psychology, group dynamics and system dynamics (Bendoly et al. 2010). This dissertation will focus on the first class, namely cognitive psychology. Cognitive psychology is further classified into heuristics and biases. Tversky and Kahneman (1974) discussed 3 heuristics and 13 cognitive biases that usually face decision makers. This dissertation is going to study 6 cognitive biases under the representativeness heuristic. The model in this dissertation states that cognitive reflection of the individual (Frederick 2005) and training about cognitive biases in the form of warning (Kaufmann and Michel 2009) will help decisions’ makers make less biased decisions. The 6 cognitive biases investigated in this dissertation are insensitivity to prior probability, insensitivity to sample size, misconception of chance, insensitivity to predictability, the illusion of validity and misconception of regression. 6 scenarios in OM contexts have been used in this study. Each scenario corresponds to one cognitive bias. Experimental design has been used as the research tool. To see the impact of training, one group of the participants received the scenarios without training and the other group received them with training. The training consists of a brief description of the cognitive bias as well as an example of the cognitive bias. Cognitive reflection is operationalized using cognitive reflection test (CRT). The survey was distributed to students at University of North Texas (UNT). Logistic regression has been employed to analyze data. The research shows that participants show the cognitive biases proposed by Tversky and Kahneman. Moreover, CRT is significant factor to predict the cognitive bias in two ...
Community-based Logistics and Supply Chain Management: Developing, Testing and Validating Conceptual Models
The field of Logistics and Supply Chain Management (LSCM) suggests that transactions, collaboration, and value are important in the supply and delivery of products and services to meet the need of impoverished end-consumers. In many cases, the application of LSCM is paramount in most strategic decision-making efforts. Therefore, this research explores the applications of LSCM processes and activities within the community-based context. The methodology used to address the research questions consisted of a hybrid of mixed methods. This mixed methodology provides three essays that investigate the application and development of LSCM in the community-based context. The essays address the flow of charitable products and services through supply chains. The dissertation does not pay close attention to the first-tier suppliers’ suppliers, which is looking at the originating flow of goods and services (raw materials, manufacturing, etc.). However, the dissertation puts a focus on products and services supplied to focal organizations and how these products are then passed on to end-consumers. Essay I looks at the transaction (costs) that ensue from the supply of charitable products. Essay II analyzes a social service ecosystem and investigates how the network of organizations enable the distribution of charitable products and services. Lastly, Essay III examines the delivery of valuable services to the end-consumers, and what tools Community-Based Enterprises (CBEs) should focus on to develop and retain end-consumers in impoverished communities. The research provides conceptual models that review some fundamental LSCM achievement gaps in supplying, delivering and providing social services to end users within impoverished communities. The dissertation draws upon literature from the fields of economics, marketing, social science, and logistics and supply chain management. The dissertation uses the primary research method of unstructured and semi-structured interviews, case studies, written survey instruments and system dynamics within three studies. The studies resolve to look into the term ...
Stable Nanocrystalline Au Film Structures for Sliding Electrical Contacts
Hard gold thin films and coatings are widely used in electronics as an effective material to reduce the friction and wear of relatively less expensive electrically conductive materials while simultaneously seeking to provide oxidation resistance and stable sliding electrical contact resistance (ECR). The main focus of this dissertation was to synthesize nanocrystalline Au films with grain structures capable of remaining stable during thermal exposure and under sliding electrical contact stress and the passing of electrical current. Here we have utilized a physical vapor deposition (PVD) technique, electron beam evaporation, to synthesize Au films modified by ion implantation and codeposited ZnO hardened Au nanocomposites. Simultaneous friction and ECR experiments of low fluence (< 1x10^17 cm^-2) He and Ar ion implanted Au films showed reduction in friction coefficients from ~1.5 to ~0.5 and specific wear rates from ~4x10^-3 to ~6x10^-5 mm^3/N·m versus as-deposited Au films without significant change in sliding ECR (~16 mΩ). Subsurface microstructural changes of He implanted films due to tribological stress were analyzed via site-specific cross-sectional transmission electron microscopy (TEM) and revealed the formation of nanocrystalline grains for low energy (22.5 keV) implantation conditions as well as the growth and redistribution of cavities. Nanoindentation hardness results revealed an increase from 0.84 GPa for as-deposited Au to ~1.77 GPa for Au uniformly implanted with 1 at% He. These strength increases are correlated with an Orowan hardening mechanism that increases proportionally to (He concentration)1/3. Au-ZnO nanocomposite films in the oxide dilute regime (< 5 vol% ZnO) were investigated for low temperature aging stability in friction and ECR. Annealing at 250 °C for 24 hours Au-(2 vol%)ZnO retained a friction coefficient comparable to commercial Ni hardened Au of ~ 0.3 and sliding ECR values of ~35 mΩ. Nanoindentation hardness increases of these films (~2.6 GPa for 5 vol% ZnO) are correlated to ...
Microstructural Phase Evolution In Laser Deposited Compositionally Graded Titanium-Chromium Alloys
A compositionally graded Ti-xCr (10≤x≤30 wt%) alloy has been fabricated using Laser Engineered Net Shaping (LENSTM) to study the microstructural phase evolution along a compositional gradient in both as-deposited and heat treated conditions (1000°C followed by furnace cooling or air cooling). The alloys were characterized by SEM BSE imaging, XRD, EBSD, TEM and micro-hardness measurements to determine processing-structure-property relations. For the as-deposited alloy, α-Ti, β-Ti, and TiCr2 (C15 Laves) phases exist in varying phase fractions, which were influential in determining hardness values. With the furnace cooled alloy, there was more homogeneous nucleation of α phase throughout the sample with a larger phase fraction of TiCr2 resulting in increased hardness values. When compared to the air cooled alloy, there was absence of wide scale nucleation of α phase and formation of ω phase within the β phase due to the quicker cooling from elevated temperature. At lower concentrations of Cr, the kinetics resulted in a diffusionless phase transformation of ω phase with increased hardness and a lower phase fraction of TiCr2. In contrast at higher Cr concentrations, α phase separation reaction occurs where the β phase is spinodally decomposed to Cr solute-lean β1 and solute-rich β2 resulting in reduced hardness.
Unpacking Self in Clutter and Cloth: Curator as Artist/Researcher/Teacher
This a/r/tographic dissertation offers opportunities to interrogate curator identity and curator ways of being in both public and private spaces. Instead of an authoritative or prescriptive look at the curatorial, this dissertation as catalogue allows for uncertainty, for messiness, for vulnerable spaces where readers are invited into an exhibition of disorderly living. Stitched throughout the study are stories of mothering and the difficulties that accompanied the extremely early birth of my daughter. Becoming a mother provoked my curating in unexpected ways and allowed me to reconsider the reasons I collect, display, and perform as a curator. It was through the actual curating of familial material artifacts in the exhibition Dress Stories, I was able to map the journey of my curatorial turns. My engagement with clothing in the inquiry was informed by the work of Sandra Weber and Claudia Mitchell, where dress as a methodology allows for spaces to consider autobiography, identity, and practice. It was not until the exhibition was over, I was able to discover new ways to thread caring, collecting, and cataloging ourselves as curators, artists, researchers, teachers, and mothers. It prompts curators and teachers to consider possibilities for failure, releasing excess, and uncaring as a way to care for self, objects, and others.
Virtual Entrepreneurship: Explicating the Antecedents of Firm Performance
Prior research has examined entrepreneurial businesses spatially located in the physical or offline context; however, recent radical information and technological breakthroughs allow entrepreneurs to launch their businesses completely online. The growth of the online business industry has been phenomenal. Predictions for worldwide online sales estimate it to reach $2 trillion in 2016. Virtual entrepreneurship refers to the pursuit and exploitation of opportunities via virtual platforms. Web 2.0 cybermediaries offer web-based platforms that function similarly to traditional intermediaries in a virtual setting and minimize barriers to entry for virtual entrepreneurial firms. The use of such cybermediaries with increasing success suggests an implicit shift in the dominant logic that typically underpins the functioning of entrepreneurial firms operating in the physical world. In this relatively uncharted territory, marked by a focus on profit, cooperation, collaboration and community, three ideal-type institutional logics i.e. Market, Corporation and Community, blend together. It is posited that a Virtual Entrepreneurial Logic guides the norms, behaviors, and practices of entrepreneurial firms operating via these virtual platforms. This raises the question whether the blending of three ideal-type logics leads to the existence of different antecedents of performance. A business model antecedent addressing the economic dimension, a community antecedent addressing the community dimension and a co-creation antecedent addressing the collaborative dimension of the Virtual Entrepreneurial Logic were therefore empirically examined in this study. Thus, three research questions were investigated to explicate the antecedents. Primary data from 1396 virtual entrepreneurial firms was collected (business model antecedent n=366, community antecedent n=732 and co-creation antecedent n= 298) to test the proposed hypotheses. Results provided support for the three antecedents. This study makes important theoretical and practical contributions to understanding the domain of virtual entrepreneurship from a blended logics perspective. Using the theoretical lens provided by institutional logics helps shed light on the pivotal role ...
Social Anxiety and Non-Medical Prescription Stimulant Use among College Students
Current evidence suggests that non-medical prescription stimulant (NMPS) use is on the rise, particularly among college students. Identifying individuals at risk for regular and problematic use is a critical step towards the development of effective intervention efforts. A growing body of work has noted that individuals with elevated levels of social anxiety (SA) or social anxiety disorder are at an enhanced risk for developing substance use problems, including NMPS use disorder. Despite the relevance of SA and NMPS use among college students, no studies have attempted to examine subclinical SA or the relation between SA and NMPS use among college students specifically. Thus, the present study sought to extend this area by testing the relation of SA symptoms and NMPS use frequency among college students. A large online study of college students was conducted (N=1604) to identify 252 NMPS users (18-25 years; 68.3% female). A hierarchical linear regression was used to test the moderation of positive prescription stimulant expectancies on SA symptoms in predicting past year NMPS use frequency. A subsample of 15 participants was also brought into the lab to assess subjective (State Anxiety) and physiological (salivary cortisol) responding to a social stressor task. Overall, the current study did not provide evidence that SA, via retrospective self-report or real-time responding was related to past year NMPS use frequency. Additional research is needed to resolve the discrepancies between the present findings and prior work.
Adhesion and Surface Energy Profiles of Large-area Atomic Layers of Two-dimensional MoS2 on Rigid Substrates by Facile Methods
Two-dimensional (2D) transition metal dichalcogenides (TMDs) show great potential for the future electronics, optoelectronics and energy applications. But, the studies unveiling their interactions with the host substrates are sparse and limits their practical use for real device applications. We report the facile nano-scratch method to determine the adhesion energy of the wafer scale MoS2 atomic layers attached to the SiO2/Si and sapphire substrates. The practical adhesion energy of monolayer MoS2 on the SiO2/Si substrate is 7.78 J/m2. The practical adhesion energy was found to be an increasing function of the MoS2 thickness. Unlike SiO2/Si substrates, MoS2 films grown on the sapphire possess higher bonding energy, which is attributed to the defect-free growth and less number of grain boundaries, as well as less stress and strain stored at the interface owing to the similarity of Thermal Expansion Coefficient (TEC) between MoS2 films and sapphire substrate. Furthermore, we calculated the surface free energy of 2D MoS2 by the facile contact angle measurements and Neumann model fitting. A surface free energy ~85.3 mJ/m2 in few layers thick MoS2 manifests the hydrophilic nature of 2D MoS2. The high surface energy of MoS2 helps explain the good bonding strength at MoS2/substrate interface. This simple adhesion energy and surface energy measurement methodology could further apply to other TMDs for their widespread use.
Development of an Instrument to Measure the Level of Acceptability and Tolerability of Cyber Aggression: Mixed-Methods Research on Saudi Arabian Social Media Users
Cyber aggression came about as a result of advances in information communication technology and the aggressive usage of the technology in real life. Cyber aggression can take on many forms and facets. However, the main focus of this study is cyberbullying and cyberstalking through information sharing practices that might constitute digital aggressive acts. Human aggression has been extensively investigated. Studies focusing on understanding the causes and effects that can lead to physical and digital aggression have shown the prevalence of cyber aggression in different settings. Moreover, these studies have shown strong relationship between cyber aggression and the physiological and physical trauma on both perpetrators and their victims. Nevertheless, the literature shows a lack of studies that could measure the level of acceptance and tolerance of these dangerous digital acts. This study is divided into two main stages; Stage one is a qualitative pilot study carried out to explore the concept of cyber aggression and its existence in Saudi Arabia. In-depth interviews were conducted with 14 Saudi social media users to collect understanding and meanings of cyber aggression. The researcher followed the Colaizzi’s methods to analyze the descriptive data. A proposed model was generated to describe cyber aggression in social media applications. The results showed that there is a level of acceptance to some cyber aggression acts due to a number of factors. The second stage of the study is focused on developing scales with reliable items that could determine acceptability and tolerability of cyber aggression. In this second stage, the researcher used the factors discovered during the first stage as source to create the scales’ items. The proposed methods and scales were analyzed and tested to increase reliability as indicated by the Cronbach’s Alpha value. The scales were designed to measure how acceptable and tolerable is cyber-bullying, cyber-stalking in Saudi ...
With the Earth in Mind: Ecological Grief in the Contemporary American Novel
"With the Earth in Mind" responds to some of the most cutting-edge research in the field of ecocriticism, which centers on ecological loss and the grief that ensues. Ecocritics argue that ecological objects of loss abound--for instance, species are disappearing and landscapes are becoming increasingly compromised--and yet, such loss is often deemed "ungrievable." While humans regularly grieve human losses, we understand very little about how to genuinely grieve the loss of nonhuman being, natural environments, and ecological processes. My dissertation calls attention to our society's tendency to participate in superficial nature-nostalgia, rather than active and engaged environmental mourning, and ultimately activism. Herein, I investigate how an array of postwar and contemporary American novels represent a complex relationship between environmental degradation and mental illness. Literature, I suggest, is crucial to investigations of this problem because it can reveal the human consequences of ecological loss in a way that is unavailable to political, philosophical, scientific, and even psychological discourse.
A Phenomenology of Fostering Learning: Alternate Reality Games and Transmedia Storytelling
This dissertation presents the essence of the experience of instructional designers and instructors who have used alternate reality games (ARGs) and transmedia storytelling (TS) for teaching and learning. The use of game-like narratives, such as ARGs and TS, is slowly increasing. However, we know little about the lived experiences of those who have implemented such transmedia experiences in formal or informal learning. The data consists of written transcripts from interviews with 11 co-researchers in the United States and Europe. Phenomenology was the guiding methodology. The study begins by reviewing storytelling and the use of games in learning, leading up to exploring the tradition of using ARGs and TS in learning contexts. The analysis was one of reduction leading to codes, summary stories, themes, and the essence of the experience. Co-researchers used many techniques to enlighten their learners including problem-solving, critical thinking, collaboration, encouragement, disruption, and connection-making. When successful, connection-making facilitates learner agency development by providing learners with the power to act by their own initiative. Action came through the communicated narratives and games that closely tied to real-world problems. In the context of these efforts, this study's co-researchers emerged as educational life-world learning-coaches, "sensei", who were each using strategies and techniques to move students toward meaningful real-world learning and the ability to make a difference in the world. The dissertation closes by exploring implications of this study for instructional designers and instructors interested in using alternate reality games and transmedia storytelling for teaching and learning purposes.
Predicting Posttraumatic Stress Disorder Symptoms During Adolescence: A Longitudinal Study of The Role of Hypothalamic-Pituitary-Adrenal (HPA) Axis Dysfunction
Posttraumatic stress disorder (PTSD) is a trauma-related disorder that may develop in response to traumatic or stressful events. Dysfunction of the Hypothalamic-Pituitary-Adrenal (HPA) axis has been implicated in the disorder. Studies support such dysfunction as being a consequence of PTSD, rather than a precursor. However, most studies of the HPA are either cross-sectional or have been carried out in adults. The aim of the present study was to identify whether HPA dysregulation interacts with stressful experiences to increase the likelihood of developing PTSD symptoms in a community-recruited sample of healthy adolescent girls. Adolescent girls (N = 550) and one of their parents participated. Adolescents’ clinical symptoms were assessed at baseline and at a nine month follow-up. Saliva samples were collected from all adolescent participants at waking, 30 minutes after waking, and 8 pm on 3 consecutive days. Flattened diurnal slope of cortisol at baseline was associated with increased PTSD symptoms nine months later. Baseline cortisol awakening response (CAR) per se was not prospectively related to developing PTSD symptoms, but its interactions with stressful experience was associated with elevated PTSD symptoms at follow-up. Effects were small and need to be replicated in samples with more severe stressors, as well as more clinical levels of PTSD. Nevertheless, findings suggest that dysregulated basal HPA functioning may be involved in the development of PTSD symptoms.
Quantum Coherent Control and Propagation in Lambda System
Strong coherence in quasi-resonant laser driven system interferes with effective relaxations, resulting in behaviors like, coherent population trapping and Electromagnetically induced transparency. The Raman system can optimize this utilizing excited coherence in the lambda system when exposed to counter- intuitive pump-stokes pulses. The phenomenon can result in complete population transfer between vibrational levels called Stimulated Raman adiabatic passage(STIRAP). STIRAP and CHIRAP have been studied with Gaussian and chirped pulses. The optical propagation effects in dense medium for these phenomenon is studied to calculate the limitations and induced coherences. Further, the effect of rotational levels has been investigated. The molecular vibrational coherence strongly depends on the effect of rotational levels. The change in coherence interaction for ro-vibrational levels are reported and explained. We have considered the effects on the phase of radiation related to rotational mechanical motion of quantum system by taking advantages in ultra strong dispersion medium provided by quantum coherence in lambda system. The enhanced Fizeau effect on a single atom is observed.
Role of Combat Exposure and Insomnia in Student Veterans' Adaptation to College
Since 2002, the number of veterans enrolled in universities has nearly doubled, although 30-40% of veterans fail to complete their degree. While research efforts to understand the challenges veterans face transitioning from military life to college has increased in recent years, few studies have looked beyond the effects of post-traumatic stress disorder (PTSD). Insomnia is the most frequently reported symptom of combat veterans and can have serious implications for college students. The purpose of this study was to examine the role of insomnia and student veteran adaptation to college relative to civilian students. College students (N = 588) were administered a Background Information Questionnaire, the Insomnia Severity Index, the Deployment Risk and Resilience Inventory, and the Student Adaptation to College Questionnaire. Results revealed that students with insomnia reported significantly lower adaptation to college than students without insomnia. Student veterans reported better academic and personal-emotional adaptation to college than civilian students, while civilians reported better social adjustment than veterans. Although combat veterans without insomnia scored consistently higher academic adjustment than non-combat veterans and civilian students, when present insomnia seemed to have a greater negative effect on combat veterans’ academic adjustment relative to civilian students. Furthermore, insomnia mediated the relationship between combat exposure and veteran’s personal-emotional adjustment to college. Implications and future directions for research are discussed.
Quality Management Theory Development and Investigation of the Constructs within an Organizational Framework
Supply chain management (SCM) and quality management (QM) share some common literature and have overlapping domains that reinforce each other in the supplier and customer relationship management areas. Despite the recognized importance of supplier and customer relationships toward achieving quality goals, limited prior research examines whether SCM represents a distinct construct within the prominent existing quality focused organizational frameworks such as the Malcolm Baldrige National Quality Award (MBNQA). As a result of the absence of the SCM construct in the frameworks, the problem facing researchers is understanding the role of SCM in the implementation of QM practices within an organization. Such an understanding is key to QM theory development for the 21st century organizations. In order to conduct this investigation, we examine several well-studied quality focused organizational frameworks that are validated among the community of researchers, and, widely accepted among practitioners. However, which of these well-known quality management models serve as the best proxy for a quality focused organizational framework is an important area for research in order to better promote QM worldwide. This research involves three essays and uses a mixed methodology of qualitative and quantitative research. Essay 1 compares well-known national quality award frameworks such as the MBNQA, the Deming Prize, and the European Foundation for Quality Management (EFQM) Award through analysis of the extensive literature on each as well as examination of the government documents about the frameworks. Comparisons show the Baldrige framework most widely serves as basic model for national quality award frameworks to increase the awareness of quality and promote the best QM practices. After reviewing the categories and their weightings in the frameworks of MBNQA, the Deming Prize, and the EFQM Award, we identify opportunities to refine the frameworks and promote QM theory development. Essay 2 fills a critical research gap by assessing the ...
Analysis and Optimization of Graphene FET based Nanoelectronic Integrated Circuits
Like cell to the human body, transistors are the basic building blocks of any electronics circuits. Silicon has been the industries obvious choice for making transistors. Transistors with large size occupy large chip area, consume lots of power and the number of functionalities will be limited due to area constraints. Thus to make the devices smaller, smarter and faster, the transistors are aggressively scaled down in each generation. Moore's law states that the transistors count in any electronic circuits doubles every 18 months. Following this Moore's law, the transistor has already been scaled down to 14 nm. However there are limitations to how much further these transistors can be scaled down. Particularly below 10 nm, these silicon based transistors hit the fundamental limits like loss of gate control, high leakage and various other short channel effects. Thus it is not possible to favor the silicon transistors for future electronics applications. As a result, the research has shifted to new device concepts and device materials alternative to silicon. Carbon is the next abundant element found in the Earth and one of such carbon based nanomaterial is graphene. Graphene when extracted from Graphite, the same material used as the lid in pencil, have a tremendous potential to take future electronics devices to new heights in terms of size, cost and efficiency. Thus after its first experimental discovery of graphene in 2004, graphene has been the leading research area for both academics as well as industries. This dissertation is focused on the analysis and optimization of graphene based circuits for future electronics. The first part of this dissertation considers graphene based transistors for analog/radio frequency (RF) circuits. In this section, a dual gate Graphene Field Effect Transistor (GFET) is considered to build the case study circuits like voltage controlled oscillator (VCO) and low ...
"For the Ruined Body"
This dissertation contains two parts: Part I, "Self-Elegy as Self-Creation Myth," which discusses the self-elegy, a subgenre of the contemporary American elegy; and Part II, For the Ruined Body, a collection of poems. Traditionally elegies are responses to death, but modern and contemporary self-elegies question the kinds of death, responding to metaphorical not literal deaths. One category of elegy is the self-elegy, which turns inward, focusing on loss rather than death, mourning aspects of the self that are left behind, forgotten, or aspects that never existed. Both prospective and retrospective, self-elegies allow the self to be reinvented in the face of loss; they mourn past versions of selves as transient representations of moments in time. Self-elegies pursue the knowledge that the selves we create are fleeting and flawed, like our bodies. However by acknowledging painful self-truths, speakers in self-elegies exert agency; they participate in their own creation myths, actively interpreting and incorporating experiences into their identity by performing dreamlike scenarios and sustaining an intimate, but self-critical, voice in order to: one, imagine an alternate self to create distance and investigate the evolution of self-identity, employing hindsight and self-criticism to offer advice; two, reinterpret the past and its role in creating and shaping identity, employing a tone of resignation towards the changing nature of the self. This self-awareness, not to be confused with self-acceptance, is often the only consolation found.
Exploring Inorganic Catalysis with Electronic Structure Simulations
Organometallic catalysis has attracted significant interest from both industry and academia due to its wide applications in organic synthetic transformations. Example of such transformations include the reaction of a zinc carbenoid with olefins to form cyclopropanes. The first project is a computational study using both density functional and correlated wavefunction methods of the reaction between ethylene and model zinc carbenoid, nitrenoid and oxenoid complexes (L-Zn-E-X, E = CH2, NH or O, L = X = I or Cl). It was shown that cyclopropanation of ethylene with IZnCH2I and aziridination of ethylene with IZnNHI proceed via a single-step mechanism with an asynchronous transition state. The reaction barrier for the aziridination with IZnNHI is lower than that of cyclopropanation. Changing the leaving group of IZnNHI from I to Cl, changes the mechanism of the aziridination reaction to a two-step pathway. The calculation results from the epoxidation with IZnOI and ClZnOCl oxenoids suggest a two-step mechanism for both oxenoids. Another important example of organometallic catalysis is the formation of alkyl arenes from arenes and olefins using transition metal catalysis (olefin hydroarylation). We studied with DFT methods the mechanism of a novel Rh catalyst (FlDAB)Rh(TFA)(η2–C2H4) [FlDAB = N,N’ -bis(pentafluorophenyl)-2,3-dimethyl-1,4-diaza-1,3-butadiene; TFA = trifluoroacetate] that converts benzene, ethylene and air-recyclable Cu(II) oxidants to styrene. Possible mechanisms are discussed.
Evaluating the Pulse Sensor as a Low-Cost and Portable Measurement of Blood Pulse Waveform
This study was aimed at determining whether the digital volume pulse waveform using the Pulse Sensor can be used to extract features related to arterial compliance. The Pulse Sensor, a low-cost photoplethysmograph, measures green light reflection in the finger and generates output, which is indicative of blood flow and can be read by the low-cost Arduino UNO™. The Pulse Sensor code was modified to increase the sampling frequency and to capture the data in a file, which is subsequently used for waveform analysis using programs written in the R system. Waveforms were obtained using the Pulse Sensor during two 30-s periods of seated rest, in each of 44 participants, who were between the ages of 20 and 80 years. For each cardiac cycle, the first four derivatives of the waveform were calculated and low-pass filtered by convolution before every differentiation step. The program was written to extract 19 features from the pulse waveform and its derivatives. These features were selected from those that have been reported to relate to the physiopathology of hemodynamics. Results indicate that subtle features of the pulse waveform can be calculated from the fourth derivative. Feature misidentification occurred in cases of saturation or low voltage and resulted in outliers; therefore, trimmed means of the features were calculated by automatically discarding the outliers. There was a high efficiency of extraction for most features. Significant relationships were found between several of the features and age, and systolic, diastolic, and mean arterial blood pressure, suggesting that these features might be employed to predict arterial compliance. Further improvements in experimental design could lead to a more detailed evaluation of the Pulse Sensor with respect to its capability to predict factors related to arterial compliance.
The Effectiveness of a Professional Learning Community on Student Achievement in Elementary Reading and Mathematics in a Large Urban School District
The study was to determine the impact of a Professional Learning Community on student achievement as measured by the state's criterion referenced reading and mathematics achievement tests. Data for this study were extracted from the school district's student database. Two cohorts of 90 students each were randomly selected from a population of approximately 600 students in 3 schools that participated in a Professional Learning Community (treatment) and 3 schools that did not (control). Professional Learning Communities known as PLCs, can serve as a major theoretical framework to promote the improvement of classroom teachers' instructional practice, teacher effectiveness and student achievement. Reading and mathemtics mean scale scores were extracted at three time points (year 1, year 2, and year 3) across three grades (grade 3, grade 4 and grade 5). Test for equality of variance found that no statistically significant difference existed between the mean scale scores of the two cohorts at the beginning of the study. The findings revealed that both cohorts trend toward increased academic achievement from year to year individually; however, when compared to each other, no statistically significant difference existed. Further research is indicated to examine each PLC for implementation, support and leadership as they relate to the PLC and a focus on instruction and learning.
Reactions and Interfacial Behaviors of the Water–Amorphous Silica System from Classical and Ab Initio Molecular Dynamics Simulations
Due to the wide application of silica based systems ranging from microelectronics to nuclear waste disposal, detailed knowledge of water-silica interactions plays an important role in understanding fundamental processes, such as glass corrosion and the long term reliability of devices. In this dissertation, atomistic computer simulation methods have been used to explore and identify the mechanisms of water-silica reactions and the detailed processes that control the properties of the water-silica interfaces due to their ability to provide atomic level details of the structure and reaction pathways. The main challenges of the amorphous nature of the silica based systems and nano-porosity of the structures were overcome by a combination of simulation methodologies based on classical molecular dynamics (MD) simulations with Reactive Force Field (ReaxFF) and density functional theory (DFT) based ab initio MD simulations. Through the development of nanoporous amorphous silica structure models, the interactions between water and the complex unhydroxylated internal surfaces identified the unusual stability of strained siloxane bonds in high energy ring structure defects, as well as the hydroxylation reaction kinetics, which suggests the difficulty in using DFT methods to simulate Si-O bond breakage with reasonable efficiency. Another important problem addressed is the development of silica gel structures and their interfaces, which is considered to control the long term residual dissolution rate in borosilicate glasses. Through application of the ReaxFF classical MD potential, silica gel structures which mimic the development of interfacial layers during silica dissolution were created A structural model, consisting of dense silica, silica gel, and bulk water, and the related interfaces was generated, to represent the dissolution gel structure. High temperature evolution of the silica-gel-water (SGW) structure was performed through classical MD simulation of the system, and growth of the gel into the water region occurred, as well as the formation of intermediate range structural ...
Lipidomic Analysis of Single Cells and Organelles Using Nanomanipulation Coupled to Mass Spectrometry
The capability to characterize disease states by way of determining novel biomarkers has led to a high demand of single cell and organelle analytical methodologies due to the unexpected heterogeneity present in cells of the same type. Lipids are of particular interest in the search for biomarkers due to their active roles in cellular metabolism and energy storage. Analyzing localized lipid chemistry from individual cells and organelles is challenging however, due to low analyte volume, limited discriminate instrumentation, and common requirements of separation procedures and expenditure of cell sample. Using nanomanipulation in combination with mass spectrometry, individual cells and organelles can be extracted from tissues and cultures in vitro to determine if heterogeneity at the cellular level is present. The discriminate extraction of a single cell or organelle allows the remainder of cell culture or tissue to remain intact, while the high sensitivity and chemical specificity of mass spectrometry provides structural information for limited volumes without the need for chromatographic separation. Mass analysis of lipids extracted from individual cells can be carried out in multiple mass spectrometry platforms through direct-inject mass spectrometry using nanoelectrospray-ionization and through matrix-assisted laser/desorption ionization.
Welcome to the Rest of It
This creative nonfiction dissertation is a book of essays that explore the author's life and relationship to Upstate New York. The project also connects this experience to gender and trauma. Though the topics range from local history to cosmetic surgical procedures, the essays are collected by how they illuminate cultural tensions and universal truths. These essays are preceded by a critical preface that examines the differences between essays collections, books of essays, and argues for the recognition of narrative nonfiction as an artistic choice.
Developing Policy for a Tech Program Based on Understanding Organizational Practices
This thesis contributes to research that informs the studies of organizational management and organizational anthropology. It examines the internal hierarchy and organizational practices of a Tech Company and describes how findings contributed to policy recommendations aimed towards supporting a “guild” model for organizational success. The data collecting and research were undertaken while working as an employee of the Tech Program and subsequent analysis continued past the end of that phase of work. Methods included semi-structured interviews which captured the sentiments and understandings of employees within the organization, and a questionnaire which revealed sentiments and experiences from former employees. These were buttressed with participant observation engaged through a participatory action research methodology. Findings add to the work directed towards understanding the effect of Founder’s Syndrome within organizations. Additionally, this thesis contributes to a growing body of research centered on best practices for fostering positive organizational growth by creating lines of communication from front-line employees to management level employers.
This dissertation is has two parts: a critical essay on the lyric subject, and a collection of poems. In the essay, I suggest that, contrary to various anti-subjectivists who continue to define the lyric subject in Romantic terms, a strain of Post-Romantic lyric subjectivity allows us to think more in terms of space, process, and dialogue and less in terms of identity, (mere self-) expression, and dialectic. The view I propose understands the contemporary lyric subject as a confluence or parallax of imagined and felt subjectivities in which the subject who writes the poem, the subject personified as speaker in the text itself, and the subject who receives the poem as a reader are each repeatedly drawn out of themselves, into others, and into an otherness that calls one beyond identity, mastery, and understanding. Rather than arguing for the lyric subject as autonomous, expressive (if fictive) "I,” I have suggested that the lyric subject is a dialogical matrix of multiple subjectivities—actual, imagined, anticipated, deferred—that at once posit and emerge from a space whose only grounded, actual place in the world is the text: not the court, not the market, and not a canon of legitimized authors, but in the relatively fugitive realm of text. In this way, there is no real contradiction between what Tucker terms the intersubjective and the intertextual. The lyric space I am arguing for is ultimately a diachronic process in which readers take up the poem and bring that space partially into their bodies, imaginations, and consciousness even as the poem brings them out, or to the edge, of each of these.
Learning from small data set for object recognition in mobile platforms.
Did you stand at a door with a bunch of keys and tried to find the right one to unlock the door? Did you hold a flower and wonder the name of it? A need of object recognition could rise anytime and any where in our daily lives. With the development of mobile devices object recognition applications become possible to provide immediate assistance. However, performing complex tasks in even the most advanced mobile platforms still faces great challenges due to the limited computing resources and computing power. In this thesis, we present an object recognition system that resides and executes within a mobile device, which can efficiently extract image features and perform learning and classification. To account for the computing constraint, a novel feature extraction method that minimizes the data size and maintains data consistency is proposed. This system leverages principal component analysis method and is able to update the trained classifier when new examples become available . Our system relieves users from creating a lot of examples and makes it user friendly. The experimental results demonstrate that a learning method trained with a very small number of examples can achieve recognition accuracy above 90% in various acquisition conditions. In addition, the system is able to perform learning efficiently.
Let the Dogs Bark: The Psychological War in Vietnam, 1960-1968
Between 1960 and 1968 the United States conducted intensive psychological operations (PSYOP) in Vietnam. To date, no comprehensive study of the psychological war there has been conducted. This dissertation fills that void, describing the development of American PSYOP forces and their employment in Vietnam. By looking at the complex interplay of American, North Vietnamese, National Liberation Front (NLF) and South Vietnamese propaganda programs, a deeper understanding of these activities and the larger war emerges. The time period covered is important because it comprises the initial introduction of American PSYOP advisory forces and the transition to active participation in the war. It also allows enough time to determine the long-term effects of both the North Vietnamese/NLF and American/South Vietnamese programs. Ending with the 1968 Tet Offensive is fitting because it marks both a major change in the war and the establishment of the 4th Psychological Operations Group to manage the American PSYOP effort. This dissertation challenges the argument that the Northern/Viet Cong program was much more effective that the opposing one. Contrary to common perceptions, the North Vietnamese propaganda increasingly fell on deaf ears in the south by 1968. This study also provides support for understanding the Tet Offensive as a desperate gamble born out of knowledge the tide of war favored the Allies by mid-1967. The trend was solidly towards the government and the NLF increasingly depended on violence to maintain control. The American PSYOP forces went to Vietnam with little knowledge of the history and culture of Vietnam or experience conducting psychological operations in a counterinsurgency. As this dissertation demonstrates, despite these drawbacks, they had considerable success in the period covered. Although facing an experienced enemy in the psychological war, the U.S. forces made great strides in advising, innovating techniques, and developing equipment. I rely extensively on untapped sources ...
Bioinspired and biocompatible coatings of poly(butylene adipate-co-terephthalate) and layer double hydroxide composites for corrosion resistance
Hierarchical arrangement of biological composites such as nacre and bone containing high filler (ceramic) content results in high strength and toughness of the natural material. In this study we mimic the design of layered bone microstructure and fabricate an optimal multifunctional bio-nanocomposite having strength, toughness and corrosion resistance. Poly (butylene adipate-co-terephthalate) (PBAT), a biodegradable polymer was used as a substrate material with the reinforcement of LDH (Layered double hydroxide) as a nanofiller in different concentrations to achieve enhancement in mechanical properties as well as processing related thermostability. Corrosion resistance was increased by mimicking a layered structured which incorporated a tortuous diffusion path.
Enhancement of Light Emission from Metal Nanoparticles Embedded Graphene Oxide
A fully oxidized state of graphene behaves as a pure insulating while a pristine graphene behaves as a pure conducting. The in-between oxide state in graphene which is the controlled state of oxide behaves as a semiconducting. This is the key condition for tuning optical band gap for the better light emitting property. The controlling method of oxide in graphene structure is known as reduction which is the mixed state of sp2 and sp3 hybrid state in graphene structure. sp2 hybridized domains correspond to pure carbon-carbon bond i.e. pristine graphene while sp3 hybridized domains correspond to the oxide bond with carbon i.e. defect in graphene structure. This is the uniqueness of the graphene-base material. Graphene is a gapless material i.e. having no bandgap energy and this property prevents it from switching device applications and also from the optoelectronic devices applications. The main challenge for this material is to tune as a semiconducting which can open the optical characteristics and emit light of desired color. There may be several possibilities for the modification of graphene-base material that can tune a band gap. One way is to find semiconducting property by doping the defects into pristine graphene structure. Other way is oxides functional groups in graphene structure behaves as defects. The physical properties of graphene depend on the amount of oxides present in graphene structure. So if there are more oxides in graphene structure then this material behaves as a insulating. By any means if it can be reduced then oxides amount to achieve specific proportion of sp2 and sp3 that can emit light of desired color. Further, after achieving light emission from graphene base material, there is more possibility for the study of non-linear optical property. In this work, plasmonic effect in graphene oxide has been focused. Mainly there are two ...
Forensic Analysis of Ink on Documents Using Direct Analyte-Probed Nanoextraction Coupled Techniques
Analzying questioned documents in a nondestructive nature has been an issue for the forensic science community. Using nondestructive techniques such as video spectral comparator does not give reliable information due to the variations in gray or color levels that are distinguished differently by analysts. Destructive techniques such as chromatography give dependable, qualitative and quantitative, information but involves altering the evidentiary value of these questioned documents. The paradox of document examination becomes a problem when document evidence is involved, especially when trying to preserve its evidentiary value and critical data is needed. Thus, a nondestructive technique has been developed to solve the loopholes in document examinations. Direct analyte-probed nanoextraction (DAPNe) is a nanomanipulation technique that extracts ink directly off the document for further examination. A watermark is left, at most, post-extraction. DAPNe utilizes a tip emitter, pre-filled with a solvent, which is controlled in x-, y-, and z-coordinates via joystick controller and aspirates/extracts using a pressure injector. The versatility of this technique lies within the solvent chemistry and its capability to be coupled to various types of instrumentation. The extraction solvent can be altered to target specific components in the ink. For example, a chelator may be added to target metal ions found in ancient inks or methanol may be added to target certain organic resins and binding agents found in modern inks. In this study, DAPNe has been coupled to nanospray ionization mass spectrometry, fluorescence microscopy, Raman spectroscopy, matrix-assisted laser desorption ionization mass spectrometry, and laser ablation to solve questioned document concerns in the area of falsified or forged documents, redacted documents, and aging studies.
Cooperative Strategy and Sources of Knowledge Integration Capability and Innovation: A Relational View
Faced with the challenges to addressing the novelties of the changing business environments (e.g., new customer requirement, changes in customers taste and preferences, the introduction of new products or services by competitors), organizations seek to build collaboration among their employees who possess complementary knowledge. Integrating complementary knowledge enhances employees' ability to address environmental challenges and foster innovation. Despite the importance of knowledge integration for innovation, integration of such knowledge becomes difficult when employees lack a shared understanding of knowledge, and when the knowledge is newly generated. Because new knowledge is tacit in nature and highly personal to a particular individual, it is difficult to articulate, making knowledge integration (KI) an arduous task. Lack of shared understanding, the presence of new knowledge, and lack of common interests in employees creates three types of knowledge boundaries – syntactic (information processing) boundaries, semantic (interpretive) boundaries, and pragmatic (political) boundaries. The presence of knowledge boundaries makes it difficult for employees to share and access their knowledge with each other. To overcome the challenges related to the knowledge boundaries, employees use boundary-spanning objects, which are common lexicons, common meaning, and common interests, to share and access their knowledge across the boundaries. Although prior studies have emphasized the importance of knowledge integration of various knowledge sources for innovations, examinations of what enhances KI capability of employees for organizational innovation remain limited. In addition, apart from Carlile, (2004) and Franco (2013), which are both case studies, other studies that examine the role of boundary spanning objects for knowledge integration are missing. The knowledge management literature also fails to measures (the success of common lexicons, common meaning, and common interests for achieving KI capability) boundary spanning objects. Therefore, in this study, new measurement items of boundary spanning objects and novelty are developed to test the hypotheses. A survey-based ...
Can Imagination Travel the Distance? Investigating the Role of Psychological Distance and Construal Level in Consumers' Elaborative Approach
Much of consumer behavior research focuses on how consumers process and evaluate information to make current decision. In contrast, many consumer choices ares are underpinned by the need to make choices that incorporate the past or future, other places, other people and other situations that are seemingly hypothetical. The imagination provides the chief means by which consumers are able to traverse this psychological distance. Construal Level Theory (CLT) explains how individuals are able to plan for the future, consider the perspective of another individual and even consider situations that are counter to reality. Construal mindsets are enacted when people form mental representations of distant objects, people, or places. In abstract construal mindsets, individuals think generally, in terms of global features of an object, person, or situation. On the other hand, concrete construal mindsets center around the detailed aspects of an object, person, or situation. These two different construal mindsets serve to help people cope with the uncertainty of the future. This is because abstract cosntruals are more likely than concrete construals to remain unchanged as distance from a future object, person, or place reduces. A number of consumer behavior settings require the use of the imagination. Sticking to a weight loss and or fitness plan, planning a vacation trip, saving for retirement and imagining what birthday gift a friend will enjoy all require imagining a psychologically distant state. Marketers generally seek to stimulate consumption by requiring consumers to imagine a consumption setting. This dissertation uses CLT to guide the hypotheses, as CLT explains how individuals deal with psychological distance by adopting a construal mindset. CLT explains differences in information processing associated with adopting a specific construal mindset and suggests how construal mindsets impact consumer information elaboration processes. This study will contribute to CLT by addressing an understudied be related area: ...
Eight-Year Course of Cognitive Functioning in Bipolar Disorder with Psychotic Features
The purpose of the current study was to examine neuropsychological functioning in patients with bipolar disorder (BD) with psychotic features. Data from a large, epidemiological study of patients with first-episode psychosis was used to examine verbal learning and working memory 10 years after onset of psychosis in patients with BD relative to patients with schizophrenia (SZ) and patients with psychotic major depressive disorder (MDD). Cross-sectional comparisons of verbal learning and working memory at the 10-year follow-up mirrored findings of relative performance at the 2-year follow-up (Mojtabai, 2000), as patients with SZ performed significantly worse than patients with psychotic affective disorders. When FEP patients' cognitive performance was examined longitudinally, all groups showed non-significant decline over time, with no significant diagnostic group differences after accounting for current symptoms. More frequent hospitalizations and longer treatment with antipsychotics were associated with poorer performance on cognitive testing 10 years after illness onset, but these associations disappeared when controlling baseline cognitive performance. Within the BD sample, current positive and negative psychotic symptoms were associated with poorer performance on cognitive testing. After controlling for baseline cognitive performance, markers of clinical course were unrelated to cognitive performance, consistent with existing literature on longitudinal cognitive functioning in patients with BD. The current findings support a neurodevelopmental model of verbal learning and working memory deficits in patients with bipolar disorder.
Market Efficiency, Arbitrage and the NYMEX Crude Oil Futures Market
Since Engle and Granger formulated the concept of cointegration in 1987, the literature has extensively examined the unbiasedness of the commodity futures prices using the cointegration-based technique. Despite intense attention, many of the previous studies suffer from the contradicting empirical results. That is, the cointegration test and the stationarity test on the differential contradict each other. In marked contrast, my dissertation develops the no-arbitrage cost-of-carry model in the NYMEX light sweet crude oil futures market and tests stationarity of the spot-futures differential. It is demonstrated that the primary cause of the "cointegration paradox" is the model misspecifications resulting in omitted variable bias.
Microstructure for Enhanced Plasticity and Toughness
Magnesium is the lightest metal with a very high specific strength. However, its practical applicability is limited by its toughness and reliability. Mg, being HCP has low ductility. This makes the improvement of toughness a grand challenge in Mg alloys. Friction stir processing (FSP) is a thermomechanical technique used to effect microstructural modification. Here, FSP was utilized to affect the toughness of WE43 sheets through microstructural modification. Room temperature Kahn-type tests were conducted to measure the toughness of WE43 sheets. Microscopic techniques (SEM, TEM) was utilized to study the effect of various microstructural factors like grain size, texture, constituent particles, precipitates on crack initiation and propagation. Tensile properties were evaluated by mini-tensile tests. Crack growth in WE43 sheets was also affected by mechanics and digital image correlation (DIC) was utilized to study the plastic zone size. The underlying mechanisms affecting toughness of these sheets were understood which will help in formulating ways in improving it. WE43 nanocomposites were fabricated via FSP. Uniform distribution of reinforcements was obtained in the composites. Improved mechanical properties like that of enhanced strength, increased hardness and stiffness were obtained. But contrary to other metal matrix composites which show reduction in ductility with incorporation of ceramic reinforcements, the nanocomposites showed good strength-ductility combination. The composites were precisely characterized and mechanisms governing this property were studied. The nano-length of the reinforcements was observed to be the main criteria and the dislocation-particle interaction, the main reason behind the strength-ductility property.
Lifecycle Affordability Decisions
SpaceX as aerospace manufacturer and space transport service technology company work along to make reusable rockets, their long term plan is to make spaceflight affordable routine. Elon Musk, as CEO, is involved in every step of decision making as he has mentioned in interviews. The rocket's engine has undergone a number of improvements, and to increase its efficiency and power, a number of parts has been reduced. The redesigning process involves several decisions, such as in-house or out-source production. This research provides a practical framework for contractors, suppliers, and manufacturers to build a more reliable, affordable, and low cost supply chain. As a result, the objective of my dissertation is to explore how managers can extend the useful life of their assets and reduce their total cost of ownership. The main research focus for this dissertation is lifecycle affordability (LCA) for capital intensive products when post production costs are significantly higher than production costs. Lifecycle cost is often not considered by firms in a product, service or asset when making acquisition decisions. Firm's acquisition are mainly based on the initial cost of the product. Decision making without considering the entire lifecycle cost of a product impacts the firm's profitability, revenue, pricing strategies, and competitiveness. Evaluating the trade-offs between all the costs involved in the product lifecycle can help firms to have an estimation of costs before making any acquisition decisions. To address these challenges, lifecycle affordability (LCA) considerations can enable firms to focus their decisions on their long-term investment process rather than trying to save on initial cost of purchasing a product. This dissertation presents the following research question: how has lifecycle affordability been represented in supply chain research to date? And what are constructs of lifecycle affordability? To address this research question, the dissertation is comprised of three separate ...
Effects of UE Speed on MIMO Channel Capacity in LTE
With the introduction of 4G LTE, multiple new technologies were introduced. MIMO is one of the important technologies introduced with fourth generation. The main MIMO modes used in LTE are open loop and closed loop spatial multiplexing modes. This thesis develops an algorithm to calculate the threshold values of UE speed and SNR that is required to implement a switching algorithm which can switch between different MIMO modes for a UE based on the speed and channel conditions (CSI). Specifically, this thesis provides the values of UE speed and SNR at which we can get better results by switching between open loop and closed loop MIMO modes and then be scheduled in sub-channels accordingly. Thus, the results can be used effectively to get better channel capacity with less ISI. The main objectives of this thesis are: to determine the type of MIMO mode suitable for a UE with certain speed, to determine the effects of SNR on selection of MIMO modes, and to design and implement a scheduling algorithm to enhance channel capacity.
Opera and Society in Early-Twentieth-Century Argentina: Felipe Boero's El matrero
Premiering at the twilight of the gauchesco era and the dawn of Argentine musical Modernism, El matrero (1929) by Felipe Boero (1884-1958) remains underexplored in terms of its social milieu and artistic heritage. Instantly hailed as a masterpiece, the work retains a place in the local repertory, though it has never been performed internationally. The opera draws on myths of the gaucho and takes further inspiration from the energized intellectual environment surrounding the one-hundred-year anniversary of Argentine Independence. The most influential writers of the Centenary were Leopoldo Lugones (1874-1938), Ricardo Rojas (1882-1957), and Manuel Gálvez (1882-1962). Their times were marked by contradictions: xenophobia and the desire for foreign approbation; pride in an imaginary, "barbaric" yet noble ideal wiped out by the "civilizing" ambitions of revered nineteenth-century leaders. Krausism, a system of ideas following the teachings of Karl Friedrich Krause (1781-1832), had an impact on the period as exhibited in the political philosophy of Hipólito Yrigoyen (1852-1933), who served as president from 1916 to 1922 and 1928 to 1930 when he was deposed by a right-wing coup d'état. Uncritical applications of traditional understandings of nationalism have had a negative impact on Latin American music scholarship. A distillation of scholarly conceptions of Argentine nacionalismo, which address the meaning of the word as it was used in the early twentieth century, combined with an examination of major works of important literary figures of the Centenary provide a firmer ground for discussion. Gálvez paints a conservative portrait of a refined, well-traveled dilettante who finds true enlightenment only in his own rural, Argentine culture. A liberal, Rojas understands nationalism as devotion to the development of national institutions and local art. Lugones argues the foundation of national art should be the gaucho, and articulates the hierarchical sociabilities it should articulate. Boero adopts elements of Krausism and ...
Data-Driven Decision-Making Framework for Large-Scale Dynamical Systems under Uncertainty
Managing large-scale dynamical systems (e.g., transportation systems, complex information systems, and power networks, etc.) in real-time is very challenging considering their complicated system dynamics, intricate network interactions, large scale, and especially the existence of various uncertainties. To address this issue, intelligent techniques which can quickly design decision-making strategies that are robust to uncertainties are needed. This dissertation aims to conquer these challenges by exploring a data-driven decision-making framework, which leverages big-data techniques and scalable uncertainty evaluation approaches to quickly solve optimal control problems. In particular, following techniques have been developed along this direction: 1) system modeling approaches to simplify the system analysis and design procedures for multiple applications; 2) effective simulation and analytical based approaches to efficiently evaluate system performance and design control strategies under uncertainty; and 3) big-data techniques that allow some computations of control strategies to be completed offline. These techniques and tools for analysis, design and control contribute to a wide range of applications including air traffic flow management, complex information systems, and airborne networks.
An Experimental Study of Bifurcated (Weekend and Weekday) and Unitary (Past Week) Retrospective Assessments of Sleep
Discordance between weekday and weekend sleep schedules is common (Bonnet & Arand, 1995; Breslau, Roth, Rosenthal, & Andreski, 1997; Machado, Varella, & Andrade, 1998; Strauch & Meier, 1988; Tsai & Li, 2004). Brief retrospective self-report measures are essential for epidemiological research studies (Moul, Hall, Pilkonis, & Buysse, 2004), but self-reports are prone to error in recall, and the greater the variability in nightly sleep, the less reliable are retrospective reports (Babkoff, Weller, & Lavidor, 1996). More accurate self-report responses may be possible if measures prompt participants to consider variations in sleep schedules that are consistent (i.e., weekday and weekend sleep schedules). The current study experimentally examined whether Bifurcated (Weekday and Weekend) retrospective assessments of sleep are more accurate than Unitary (Past Week) assessments. Participants were randomly assigned to complete one of the two versions (Bifurcated vs. Unitary) of the Sleep Questionnaire. One hundred and thirty-one participants were included in the analyses. Results of a a series of analyses demonstrated that the Bifurcated version of the Sleep Questionnaire provided more accurate and less variable estimates of total sleep time than the Unitary version of the Sleep Questionnaire. Differences between the versions of the Sleep Questionnaire for other sleep variables were less consistent, and the increased length of the Bifurcated version of the Sleep Questionnaire may have contributed to increased missing and unusable data in this group. Overall, the findings suggest that in both research and clinical work, retrospective measures that examine weekday and weekend sleep separately may offer advantages over retrospective measures that do not differentiate between weekday and weekend sleep.
Scripture for America: Scriptural Interpretation in John Locke's Paraphrase
Is John Locke a philosopher or theologian? When considering Locke's religious thought, scholars seldom point to his Paraphrase and Notes on the Epistles of St. Paul. This is puzzling since the Paraphrase is his most extensive treatment of Christian theology. Since this is the final work of his life, did Locke undergo a deathbed conversion? The scholarship that has considered the Paraphrase often finds Locke contradicting himself on various theological doctrines. In this dissertation, I find that Locke not only remains consistent with his other writings, but provides his subtlest interpretation of Scripture. He is intentionally subtle in order to persuade a Protestant audience to modern liberalism. This is intended to make Protestantism, and specifically Calvinism, the vehicle for modern liberalism. This is seen clearly in Max Weber's The Protestant Ethic and the Spirit of Capitalism. Though Weber concludes that Protestant support for capitalism in the late 19th Century is due to its theological foundation, I find that Weber is actually examining Lockean Protestantism. Locke's success in transforming Protestantism is also useful today in showing how a modern liberal can converse with someone who actively opposes, and may even wish to harm, modern liberalism. The dissertation analyzes four important Protestant doctrines: Faith Alone, Scripture Alone, the church and family, and Christian political life.
Extensions of the General Linear Model into Methods within Partial Least Squares Structural Equation Modeling
The current generation of structural equation modeling (SEM) is loosely split in two divergent groups - covariance-based and variance-based structural equation modeling. The relative newness of variance-based SEM has limited the development of techniques that extend its applicability to non-metric data. This study focuses upon the extension of general linear model techniques within the variance-based platform of partial least squares structural equation modeling (PLS-SEM). This modeling procedure receives it name through the iterative PLS‑SEM algorithm's estimates of the coefficients for the partial ordinary least squares regression models in both the measurement model and the overall structural model. This research addresses the following research questions: (1) What are the appropriate measures for data segmentation within PLS‑SEM? (2) What are the appropriate steps for the analysis of rank-ordered path coefficients within PLS‑SEM? and (3) What is an appropriate model selection index for PLS‑SEM? The limited type of data to which PLS-SEM is applicable suggests an opportunity to extend the method for use with different data and as a result a broader number of applications. This study develops and tests several methodologies that are prevalent in the general linear model (GLM). The proposed data segmentation approaches posited and tested through post hoc analysis of structural model. Monte Carlo simulation allows demonstrating the improvement of the proposed model fit indices in comparison to the established indices found within the SEM literature. These posited PLS methods, that are logical transfers of GLM methods, are tested using examples. These tests enable demonstrating the methods and recommending reporting requirements.
"Counting Out The Harvest"
"Counting Out The Harvest" is a collection of poems exploring intimate encounters. The poems reflect on encounters with memories, family, and the natural and cosmic worlds. In one of the poems, "Red-Throated Anole," the speaker works desperately to save a small dying lizard. In "Ice Storm, Post-Divorce," the speaker attempts to decipher a cluster of ladybugs taking refuge in her room. In the title poem, a couple wonders patiently if their crop will eventually grow. In each of these poems there is a present longing for the construction of a meaningful identity by means of the encounter, but the intersection between speaker and world falls short of satisfaction, whether the faultiness lies in the body's inability to find full sustenance, or in the ever-changing fluidity of memory to find stability. But the poems progress from pressing against this difficulty toward finding a contented resignation to the world's cyclical order. The final line of the manuscript, "disrobe a layer to begin again," indicates an arrival at satisfaction, which is found ultimately in continuation.
Customers' Attitudes toward Mobile Banking Applications in Saudi Arabia
Mobile banking services have changed the design and delivery of financial services and the whole banking sector. Financial service companies employ mobile banking applications as new alternative channels to increase customers' convenience and to reduce costs and maintain profitability. The primary focus of this study was to explore the Saudi bank customers' perceptions about the adoption of mobile banking applications and to test the relationships between the factors that influence mobile banking adoption as independent variables and the action to adopt them as the dependent variable. Saudi customers' perceptions were tested based on the extended versions of IDT, TAM and other diffusion of innovation theories and frameworks to generate a model of constructs that can be used to study the use and the adoption of mobile technology by users. Koenig-Lewis, Palmer, & Moll's (2010) model was used to test its constructs of (1) perceived usefulness, (2) perceived ease of use, (3) perceived compatibility, (4) perceived credibility, (5) perceived trust, (6) perceived risk, and (7) perceived cost, and these were the independent variables in current study. This study revealed a high level of adoption that 82.7% of Saudis had adopted mobile banking applications. Also, the findings of this study identified a statistically significant relationship between all of demographic differences: gender, education level, monthly income, and profession and mobile banking services among adopters and non-adopters. Seven attributes relating to the adoption of mobile banking applications were evaluated in this study to assess which variables affected Saudi banks customers in their adoption of mobile banking services. The findings indicated that the attributes that significantly affected the adoption of mobile banking applications among Saudis were perceived trust, perceived cost, and perceived risk. These three predictors, as a result, explained more than 60% of variance in intention to adopt mobile banking technology in Saudi Arabia. ...