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Accelerated Corrosion Test with Operation Simulation of All-Aluminum Microchannel Heat Exchangers

Description: The HVAC&R industry is looking to transition from copper-aluminum heat exchangers to all-aluminum microchannel technology. The want for the transition stemmed from seeing the performance improvement of all-aluminum microchannel radiators in the automotive industry. Applications differ between the two industries; therefore, applying this technology for HVAC&R use must be validated. Research towards operating modes of an all-aluminum heat exchanger in a defined corrosive environment will provide the industry with a better understanding of heat exchanger design and heat exchanger material selection. The worth in this is preventing overdesign and producing more efficient heat exchangers. Furthermore, ASHRAE members and the corrosion community will find value in a defined corrosion system and corrosion test procedure. The information gained through past research has progressed assessment of material performance; however, the methods improperly simulate and expedite natural weathering. The most common method being used is the ASTM (American Society of Testing Materials) Sea Water Acetic Acid Test. The research discussed in this paper was focused on improving a standard corrosion system by implementing system modifications to simulate heat exchanger operation while performing a modified wet-dry cyclic test (e.g. ASTM G85 Annex 5). The goal is to produce results that are more representative of natural corrosion behavior and its forms. Current results were gathered from five of ten samples that underwent initial testing. Finally, possible improvements towards the chamber system and the test method, including the salt solution, are discussed.
Date: May 2016
Creator: Vaughan, Haydn

Adhesion and Surface Energy Profiles of Large-area Atomic Layers of Two-dimensional MoS2 on Rigid Substrates by Facile Methods

Description: 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.
Date: May 2016
Creator: Wu, Min

Analysis and Optimization of Graphene FET based Nanoelectronic Integrated Circuits

Description: 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 ...
Date: May 2016
Creator: Joshi, Shital

Angular Analysis of a Wide-Band Energy Harvester based on Mutually Perpendicular Vibrating Piezoelectric Beams

Description: The recent advancements in electronics and the advents of small scaled instruments has increased the attachment of life and functionality of devices to electrical power sources but at the same time granted the engineers and companies the ability to use smaller sources of power and batteries. Therefore, many scientists have tried to come up with new solutions for a power alternatives. Piezoelectric is a promising material which can readily produce continuous electric power from mechanical inputs. However, their power output is dependent upon several factors such as, system natural frequency, their position in the system, the direction of vibration and many other internal and external factors. In this research the working bandwidth of the system is increased through utilizing of two different piezoelectric beam in different directions. The dependency of output power with respect to rotation angle and also the frequency shift due to the rotation angle is studied.
Date: December 2016
Creator: Mirzaabedini, Sohrab

Attitudes about Caregiving: An Ethnicity by Generation Approach

Description: The goal of this project was to understand ethnic and generational differences in attitudes towards caregiving and expected burden while taking into consideration factors such as gender, generation, familism, and acculturation. One hundred and sixteen young adults (ages 18-25) and 93 middle-age adults (ages 38-62) were enrolled in the study. Participants included European Americans, African Americans, and Hispanics. Using moderation analysis, two hypotheses were investigated: 1) Ethnicity relates to attitudes towards caregiving, moderated by gender, generation, familism, and acculturation. 2) Ethnicity and expected burden relate to each other, moderated by gender, generation, familism, and acculturation. Familism emerged as a moderator in the relationship between ethnicity and expected burden. Results suggested that the strength of the relationship between being African American and expecting burden was less for those with moderate familism (R =.078), slightly higher for low familism (R = .176), and the highest for high familism (R= .261). Additional results indicated that the strength of the relationship between being Hispanic, as opposed to being European American, and expected burden, was higher for middle-aged adults (R =.23) when compared to young adults (R =.19). The current findings lend support to the recently established idea that familism is not protective against burden as it increases one's sense of obligation towards family (Knight & Sayegh, 2010).
Date: August 2016
Creator: Caballero, Daniela M

Bioinspired and biocompatible coatings of poly(butylene adipate-co-terephthalate) and layer double hydroxide composites for corrosion resistance

Description: 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.
Date: May 2016
Creator: Rizvi, Syed Hussain

Biomass-Derived Activated Carbon through Self-Activation Process

Description: 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.
Date: May 2016
Creator: Xia, Changlei

Black Males' Treatment Experiences in Mental Health Court: A Phenomenological Analysis

Description: Mental health courts (MHCs) are part of an umbrella of specialty courts in which court officials, law enforcement, and treatment providers work together to seek alternative solutions to failed traditional approaches to justice. Researchers investigating MHCs indicated that the courts may be helpful in reducing recidivism and introducing offenders with mental health disorders to treatment services. I used the qualitative method of phenomenology to understand the experiences of young adult Black male clients' perceptions of mental health treatment in MHCs. Twelve participants ranged in age from 21-40 years. The research team identified three themes -- (a) helpful treatment factors, (b) relational growth, (c) treatment barriers – and five subthemes: (a) internal growth, (b) relational growth, (c) behavioral growth, (d) factors of marginalization, and (e) interpersonal barriers. Meaning pertaining to findings and implications for research and practice are discussed.
Date: December 2016
Creator: Stare, Bryan

Brand Management Capability and Brand Performance

Description: Brands are intangible assets that provide companies with the potential to extract higher rents or prices from customers. However, only few organizations are able to build and sustain brands over a long period of time. Brand management capability - the organization's ability to build and sustain brands becomes important for achieving sustainable competitive advantage. Despite the importance of brand management capability to organizations, majority of the brand management literature has primarily focused on the consumer perspective of brands. This gap in knowledge about the components of brand management capability impedes firms from replicating brand successes, and makes them reliant on brand managers. More recently, there have been multiple calls in literature to identify marketing-related organizational capabilities, which can provide organizations with a sustainable competitive advantage. The focus on developing marketing-based capabilities comes at a time when marketing is losing its influence in organizations. To this end, the current dissertation uses organizational capability theory and literature on brand management to identify the primary resource (intellectual capital comprising of structural, human, and relational capital), organizational culture type (clan, adhocracy, hierarchy, and market), and processes (strategic brand management, internal branding, and market information processes comprising of information acquisition, information transmission, conceptual utilization, and instrument utilization), that constitute the brand management capability. This dissertation also examines the association among various components of brand management capability and brand performance. A survey-based technique was used to gather data from individuals responsible for managing brands. The data was analyzed using PLS-SEM. The results indicate that human capital, relational capital, market and hierarchy culture types, internal branding, strategic brand management, and instrument utilization are positively associated with brand performance. Structural capital, clan and adhocracy culture types, information acquisition, information transmission, and conceptual utilization are not associated with brand performance. From a research standpoint, this dissertation contributes to the ...
Date: August 2016
Creator: Iyer, Pramod P

Can Imagination Travel the Distance? Investigating the Role of Psychological Distance and Construal Level in Consumers' Elaborative Approach

Description: 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: ...
Date: August 2016
Creator: Dadzie, Charlene Ama

Can Observing Behavior Predict Performance in Conditional Discriminations?

Description: Prompts are implemented often in training procedures, to include conditional discriminations, and this can lead to prompt dependency. The current study extends a prior study that suggested that the effectiveness of supplementary visual stimuli displaying the sample and comparison was dependent on the timing in relation to the selection task, presented as a prompt or feedback, in a match-to-sample procedure. The current research examines if the differences in that effectiveness were due to differences in observing behavior in those two conditions. Measures of observing behavior were determined by making access to the individual visual stimuli contingent on clicking on the visual stimulus and keeping the cursor located on the stimulus. Participants viewed the sample comparison much less than the comparison stimulus in both the prompt and feedback conditions. Latency to select the comparison stimulus was much shorter for the prompt condition suggesting that the participants might have interacted differently with the selection task in the two conditions.
Date: December 2016
Creator: Marchini, Kevin Julian

The Castle/Nikki Heat Phenomenon: A Detailed Examination of Female Representation in Entertainment Media

Description: As entertainment reflects a culture's ideology, it is important for researchers to study its messages and subsequently its potential meanings. Entertainment has the power to inform and persuade, creating models for behavior with which the public interacts. The entertainment texts for the purpose of this study are the Castle television series and the Nikki Heat novels. Together, they create a unique multi-layer fictional world. By using postmodern, feminist, communication, and entertainment theories, the results of this study provide a tightly focused lens which views a narrow aspect of entertainment media. Each text was thoroughly examined using textual analysis, Feminist Poststructuralist Discourse Analysis, and conversation analysis. Contrary to expectations, the results indicated that the Castle and Nikki Heat texts support hegemonic ideology, particularly through the use of exaggerated stereotypes, strict gender roles, imagery, and narrative choices that help perpetuate rape culture. The discussion outlines how these results can be interpreted through the dominant messages presented in the texts. This research is intended to serve as a foundation for future research regarding entertainment media.
Date: December 2016
Creator: Skinner, Katharine Virginia

Clocks and Mirrors

Description: The essays featured in this collection highlight the gaps, as well as parallels, between mental illness and the human condition. In "Appearances," the narrator struggles with her own visual identity especially after reflecting on her Mom's own lengthy history with the mirror. In "Migrations," the lyrical voice of the narrator carries the reader through the typical day of a clinically depressed female character. Lastly, "Attempting the Fall," addresses the issues society has with mental illness by following the narrator from her suicide attempt to the mental ward.
Date: December 2016
Creator: Thies, Jaclyn Michele

Community-based Logistics and Supply Chain Management: Developing, Testing and Validating Conceptual Models

Description: 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 ...
Date: May 2016
Creator: Obaze, Yolanda

A Comparative Analysis of Digital and Paper Restaurant Menus Based on Customer Perception and Nutritional Labeling

Description: The restaurant industry is a highly customer-driven field. Therefore, it is imperative that restaurateurs consider customer expectations with regard to restaurant menus. The purpose of this experimental study is to examine the effects of menu format (i.e., paper or digital) and amount of nutritional information (i.e., extensive, brief, or none) on customer perceptions of the effectiveness, perceived ease of use, and information quality of the menu. Furthermore, this research intends to test the effect of these three menu attributes on the outcomes of value and satisfaction in order to assess the competitive advantage of one format over the other. The Cognitive Appraisal and Information Processing Theories provide structure to the proposed conceptual framework and give credence to the findings. This study also fills gaps in the present research by not only ameliorating weaknesses of extant studies, but also by examining several different aspects of restaurant menus simultaneously within a single study.
Date: December 2016
Creator: Moody, Bailey

Compostable Soy-Based Polyurethane Foam with Kenaf Core Modifiers

Description: Building waste and disposable packaging are a major component in today's landfills. Most of these are structural or thermally insulative polymer foams that do not degrade over a long period of time. Currently, there is a push to replace these foams with thermoplastic or biodegradable foams that can either be recycled or composted. We propose the use of compostable soy-based polyurethane foams (PU) with kenaf core modifiers that will offer the desired properties with the ability to choose responsible end-of-life decisions. The effect of fillers is a critical parameter in investigating the thermal and mechanical properties along with its effect on biodegradability. In this work, foams with 5%, 10%, and 15% kenaf core content were created. Two manufacturing approaches were used: the free foaming used by spray techniques and the constrained expansion complementary to a mold cavity. Structure-property relations were examined using differential scanning calorimetry (DSC), dynamic mechanical analysis (DMA), thermal conductivity, compression values, scanning electron microscopy (SEM), x-ray micro-computed tomography (micro-CT), and automated multiunit composting system (AMCS). The results show that mechanical properties are reduced with the introduction of kenaf core reinforcement while thermal conductivity and biodegradability display a noticeable improvement. This shows that in application properties can be improved while establishing a responsible end-of-life choice.
Date: August 2016
Creator: Hoyt, Zachary

Cooperative Strategy and Sources of Knowledge Integration Capability and Innovation: A Relational View

Description: 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 ...
Date: August 2016
Creator: Acharya, Chandan

"Counting Out The Harvest"

Description: "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.
Date: August 2016
Creator: Lischau, Carol

Customers' Attitudes toward Mobile Banking Applications in Saudi Arabia

Description: 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. ...
Date: August 2016
Creator: Alshara, Mohammed Ali