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An educational researcher sought to collaborate with a classroom instructor to introduce problem-based learning as a new teaching intervention. First, a classroom instructor was approached to consider how a problem-based learning instructional approach might fit with their existing curriculum plan. The researcher and the classroom teacher used a discussion framework to decide together how to best design a professional learning course meant to prepare the teacher to use the new techniques in their classroom. The teacher took the professional learning course and subsequently designed his own problem-based learning course. That course was then delivered to undergraduate students in a college senior thermo-fluids lab course. Quantitative and qualitative data describe how students recognized the connection between the lab course and their perceptions of a future career as engineers. Preliminary findings suggest the researcher and teacher professional learning codesign process contributed positively to the classroom teachers developing and delivering their own PBL course that was perceived by students to contribute positively to their content knowledge, motivation and perception of their future career as engineers. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

Paper (and other cellulose-based materials such as cotton thread and fabrics) are underexploited as materials for the construction of “high-tech” and “lab-on-a-chip” devices. One major drawback of paper is its tendency to absorb water from the environment and, with wetting, to change its mechanical properties; other challenges relate to control over the attachment of molecules (e.g. antibodies, DNA) and cells on its surface, and to the addition of electronic function. The goal of this thesis is to develop paper as a substrate for a range of applications— microfluidics, substrates for electronic systems and MEMS, low-cost diagnostics, cell biology, and optics. The approach involves chemically modifying the surface of the paper to provide new functions without altering any of its defining properties: mechanical flexibility, foldability, light weight, gas permeability, and low cost. The first part of my thesis describes the modification of paper by silanization with organosilanes such as alkyl- and fluoroalkyl trichlorosilanes in the gas phase. Here, silanization is used to lower the surface free energy of the paper and to minimize the tendency of paper to absorb liquids and vapors, and especially water. Chapter 1 and Appendix 3 demonstrate that the combination of long fluoroalkyl chains of grafted siloxanes with the micro-scale roughness and porosity of paper yielded a material that is omniphobic (both hydrophobic and oleophobic), while preserving the properties of mechanical flexibility and low resistance to transport of gas of the untreated paper. Appendix 3 shows that features of omniphobic paper can be used to construct microtiter plates and liquid-filled gas sensors using standard paper folding techniques, while Appendix 4 shows that new type of microfluidic device fabricated by carving microchannels into the surface of omniphobic paper. The resulting devices have open, unobstructed channels (with dimensions as small as 45 μm) and thus exhibit fluid dynamics similar to conventional PDMS-based microfluidics, but are much lighter and have the potential to be much less expensive than PDMS-based devices. The second part of my thesis is focused on engineering the surface of paper to enable efficient immobilization of capture and target molecules for bioanalysis. In one approach, described in Appendix 5, we exploit the ease with which the surface chemistry of paper (i.e. the surface of the cellulose fibers making up the paper) can be modified, in order to enhance the immobilization of antibodies and antigens on the surface of the paper via hydrophobic interactions, while preventing the wicking of the fluids into the paper substrate. As an application in low-cost diagnostics, we describe a low-cost electrochemical device for ELISA intended for use in resource-limited settings. In a second approach, described in Chapter 2, we developed of an efficient procedure for assembling microarrays of ssDNA and proteins on paper, at the lowest practical cost. This method starts with the synthesis of DNA oligonucleotides covalently linked to paper, and proceeds to generate ssDNA arrays that, through hybridization with complementary strands of DNA, are capable of simultaneously capturing DNA, DNA-conjugated protein antigens, and DNA-conjugated antibodies. The third part of my thesis describes the simple, inexpensive fabrication of electrodes for paper-based electrochemical systems. A first method describes, in Appendix 6, the development of inkjet printing as a method for high resolution printing of conductive patterns on omniphobic “RF” paper, both to extend its promise as a substrate for paper electronics, and to enable us to integrate it into our program in low-cost, paper based diagnostics. A second method, described in Chapter 3, circumvents the need for printing, and instead focuses on the fabrication and reconfiguration of simple, versatile, and inexpensive electroanalytical devices in which conventional stainless-steel pins—in unmodified form or after coating with a carbon paste—are used as electrodes., Chemistry and Chemical Biology

Even though engineering and science are tasked with developing solutions and knowledge for a diverse population, Black and Brown communities remain severely underrepresented in these disciplines. The problem exceeds easy solutions like "a seat at the table" and requires rethinking with whom and for whom the field designs ideas and technologies. Traditionally, underrepresented groups have felt the pressure to assimilate into dominant ways of speaking and knowing because their own languages and experiences are rarely legitimized. As a result, engineering and science have missed opportunities to draw on the creative insights which diverse individuals contribute. This situation often leads to imperfect solutions with real-life consequences for those who are overlooked and society at large. Building a team with a range of experiences is more than checking a demographic box but a necessity to avoid a future with unjust technological solutions. The education of engineers and scientists thus needs to be explicit about the benefits and practices of incorporating the perspectives of multicompetent individuals and their communities. This dissertation suggests moving beyond representation by centering the language and cognitive resources of culturally and linguistically diverse groups. Drawing upon sociocultural frameworks in science education and translanguaging scholarship, the first study of this dissertation argues that factors beyond mere flexible language boundaries influence students use of their full idiolect in engineering and science. This work provides empirical backing to the question of what would happen if we created linguistically inclusive environments for learning engineering in the early grades. The children recruited for the study participated in equivalent lessons about engineering design with three different language contexts: English, Spanish and both languages. The findings suggested the influence of broader social norms in engineering learning, particularly on students availing themselves of opportunities to draw on their repertoire. Though the learning environment afforded possibilities for students to draw on their language resources, many learners did not tap them when engaged in design. Educational and social expectations about language use made engagement in disciplinary discourses through translanguaging difficult for students. The results signal the relevance of investigating how power structures shape norms about technical and scientific talk, particularly the impact of audience. Building on the arguments from the first manuscript, the second study brings attention to the relationship between audience and language use in engineering, specifically the influence of diversity in the professoriate on choices about ways of speaking. This work uses a mixed-methods sequential explanatory design to identify the factors undergraduates consider in claims of language use in private (home) and public (school) spheres. The data included responses to a national Language Use Survey from Latinx students in STEM fields (primarily engineering) who grew up in Spanish-speaking households. The findings illustrated factors (other than adherence to language boundaries) influencing the ways people speak in the disciplines. This study documented a strong effect of audience on language choices (i.e., who STEM undergraduates talk with shapes how they use their repertoire). Students also reported making decisions about language contingent on topic and place, but the influence of these factors comes from associations with particular audiences. The interlocutors and listeners in engineering, particularly those in positions of power, exert an enormous amount of influence in language use. Inspired by the literature on audience design from sociolinguistics and justice-centered science education, this paper exposed the link between the lack of representation of faculty of color (particularly Latinx professors) and language preferences in engineering education. This work draws attention to the messages that students received from disciplinary audiences because of the lack of diversity in the professoriate. The third study investigates the relationship between language, cognition, and idea generation through the lens of situated learning traditions and frameworks of design justice in engineering. It explores the role of language in creating equitable engineering solutions by indexing the diversity of experiences within multicompetent communities. Through a virtual experiment about design, engineering students were randomly assigned to implicit instruction in the form of language conditions. All participants then received explicit instruction through a prompt. Undergraduates generated features for the next-generation household appliances either in a Spanish and English or English-only condition. After their first design, participants were explicitly prompted to think about culture and language in their considerations. Results suggested that language conditions, in alignment with the linguistic resources of students, led participants to bring into design a set of cultural and linguistic values associated with their communities. Students in the English-only condition were less predisposed to draw on the experiences of their private spheres when thinking about components for the appliance, whereas those in the both languages group were more inclined to contemplate aspects of their own communities in their work. Regardless of the condition, all students benefited from explicit instruction to incorporate culture and language features in their project considerations. Through implicit or explicit instruction, treating the ways of knowing and speaking of multicompetent students as assets for engineering resulted in design considerations that incorporate cultural and linguistic aspects of traditionally underrepresented communities. The conclusion of this dissertation presents the implications of this body of work taken as a whole for researchers and practitioners regarding language use and cognition in engineering and science as well as future scholarship in design justice. It emphasizes the importance of (i) factors (beyond flexibility in language boundaries) influencing student use of their linguistic range, (ii) audience (particularly diversity of the professoriate) when thinking about language in engineering, and (iii) diversity of experiences (indexed through language) for generating equitable design solutions for a just society. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

Although a great deal of work has been done to develop new educational innovations, in the field of engineering, few innovations have found widespread acceptance in the classroom. Therefore, frameworks that conceptualize the interactions among the variables that influence successful dissemination are critical. In this dissertation, dissemination is defined as a process of first creating an awareness of an educational innovation, then influencing the intention to adopt, the actual adoption, and finally the routine use of that innovation (Fincher, 2000; Gravestock, 2002; Hutchinson & Huberman, 1994; King, 2003). This dissertation establishes the importance of achieving three research goals: (1) developing a framework that describes the interrelationships among the characteristics of educational innovations and an organizations' readiness to disseminate, (2) having an expert panel rank the characteristics of the educational innovations and readiness of faculty members, administrators, and students to disseminate, and (3) testing whether important characteristics of educational innovations and readiness of faculty members variables are significant predictors of successful dissemination. Three papers using different methodologies were sequentially developed to achieve the research goals: (1) a systematic literature review of recent dissemination literature, (2) a Delphi study of grant recipients who had disseminated educational innovations, and (3) a survey of electrical engineering and computer science faculty members. Analysis of the results from these papers led to the following findings: (1) Ease of use of an educational innovation and care about student learning outcomes were significant predictors of intention to adopt that innovation; (2) Efficacy of faculty members toward change and valence moderated the relationship between ease of use and intention to adopt educational innovations; (3) Attitude to educational innovation moderated the relationship between ease of use and intention to adopt educational innovations and moderated the relationship between intention to adopt and adoption; and (4) Awareness of others using an educational innovation was a significant predictor of adopting an educational innovation. The results of this dissertation may be leveraged by developers, faculty members, department chairs, college deans, and grant program managers, to successfully disseminate educational innovations in engineering and technology disciplines. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

The global pandemic caused by the SARS-CoV-2 virus has underscored the need for rapid, simple, scalable, and high-throughput multiplex diagnostics in non-laboratory settings. Here we demonstrate a multiplex reverse-transcription loop-mediated isothermal amplification (RT-LAMP) coupled with a gold nanoparticle-based lateral flow immunoassay (LFIA) capable of detecting up to three unique viral gene targets in 15 min. RT-LAMP primers associated with three separate gene targets from the SARS-CoV-2 virus (Orf1ab, Envelope, and Nucleocapsid) were added to a one-pot mix. A colorimetric change from red to yellow occurs in the presence of a positive sample. Positive samples are run through a LFIA to achieve specificity on a multiplex three-test line paper assay. Positive results are indicated by a characteristic crimson line. The device is almost fully automated and is deployable in any community setting with a power source.Microfluidic paper-based analytical devices (μPADs) are foundational devices for point-of-care testing yet suffer from limitations in regard to their sensitivity and capability in handling complex assays. Here, we demonstrate an airflow-based, evaporative method that is capable of manipulating fluid flows within paper membranes to offer new functionalities for multistep delivery of reagents and improve the sensitivity of μPADs by 100–1000 times. This method applies an air-jet to a pre-wetted membrane, generating an evaporative gradient such that any solutes become enriched underneath the air-jet spot. By controlling the lateral position of this spot, the solutes in the paper strip are enriched and follow the air jet trajectory, driving the reactions and enhancing visualization for colorimetric readout in multistep assays. The technique has been successfully applied to drive the sequential delivery in multistep immunoassays as well as improve sensitivity for colorimetric detection assays for nucleic acids and proteins via loop-mediated isothermal amplification (LAMP) and ELISA. For colorimetric LAMP detection of the COVID-19 genome, enrichment of the solution on paper could enhance the contrast of the dye to more clearly distinguish between the positive and negative results to achieve a sensitivity of 3 copies of SARS-Cov-2 RNAs. For ELISA, enrichment of the oxidized TMB substrate yielded a sensitivity increase of two-to-three orders of magnitude when compared to non-enriched samples – having a limit of detection of around 200 fM for IgG. Therefore, this enrichment method represents a simple process that can be easily integrated into existing detection assays for controlling fluid flows and improving detection of biomarkers on paper. LNPs, with their lipid bilayer structure, protect fragile mRNA, extending circulation and improving cellular uptake. They can be engineered for tissue targeting and controlled release. Mouse models, due to their genetic similarity to humans, are vital for studying LNPs' biodistribution, pharmacokinetics, and therapeutic impact, as well as assessing immune responses. In this thesis, two PDMS microfluidic devices were developed for mRNA encapsulated LNPs, optimizing parameters like size, encapsulation efficiency, and zeta potential. Intraperitoneal and intravenous injections in mouse models quantitatively assessed LNP efficacy and performance. A groundbreaking high-voltage cold plasma device, paired with advanced cooling, revolutionizing biotechnology. This device enables precise detachment of adherent cells, a milestone in tissue engineering and regenerative medicine. Moreover, it enhances protein binding in ELISA assays, promising higher accuracy in diagnostics, biopharmaceuticals, and life sciences research by manipulating protein-surface interactions. This innovation redefines biotech tools, with far-reaching implications.

It is no surprise that there is a shortage of women engineers. The reasons for the shortage have been researched and discussed in myriad papers, and suggestions for improvement continue to evolve. However, there are few studies that have specifically identified the positive aspects that attract women to engineering and keep them actively engaged in the field. This paper examines how women engineers view their education, their work, and their motivation to remain in the field. A qualitative research design was used to understand the motivation and adaptability factors women use to support their decision to major in engineering and stay in the engineering profession. Women engineers were interviewed using broad questions about motivation and adaptability. Interviews were transcribed and coded, looking for common threads of factors that suggest not only why women engineers persist in the field, but also how they thrive. Findings focus on the experiences, insights, and meaning of women interviewed. A grounded theory approach was used to describe the success factors found in practicing women engineers. The study found categories of attraction to the field, learning environment, motivation and adaptability. Sub-categories of motivation are intrinsic motivational factors such as the desire to make a difference, as well as extrinsic factors such as having an income that allows the kind of lifestyle that supports the family. Women engineers are comfortable with and enjoy working with male peers and when barriers arise, women learn to adapt in the male dominated field. Adaptability was indicated in areas of gender, culture, and communication. Women found strength in the ability to "read" their clients, and provide insight to their teams. Sufficient knowledge from the field advances theory and offers strategies to programs for administrators and faculty of schools of engineering as well as engineering firms, who have interest in recruitment, and retention of female students. Future research includes expanding the research to other areas of the United States, and improving engineering education pedagogy with more active and experiential learning. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

Spatial ability represents our ability to mentally arrange, rotate, and explore objects in multiple dimensions. This ability has been found to be important for engineers and engineering students. Past research has shown that many interventions can be created to boost an individual's spatial ability. In fact, past research has indicated that engineering students significantly increase in spatial ability without an intervention while they are enrolled in certain engineering courses. Some researchers have claimed that the spatial ability boosts are permanent after an intervention. However, most researchers do not check the validity of that claim with continued assessment after more than a week past the end of an intervention. Additionally, if engineering education researchers are trying to measure the impact of their separate spatial ability intervention while the participating engineering students are actively enrolled in engineering courses, a confounding variable is introduced as the courses can impact students' spatial ability. To resolve this, the work presented in this paper reflects research on engineering students' spatial ability maintenance during the winter break between semesters. It was found that newer students exhibit spatial ability improvement during the break, while older students maintain their spatial ability at the same level. A deeper statistical analysis revealed that there are other factors that play a role in spatial ability changes over the break that are more significant than how far students had progressed in their studies. Those factors include with academic performance, the sex of the students, playing music during the break, and prior life experiences. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

The flexibility and insulating nature of polymeric dielectric materials are widely used in robotic and wearable electronic devices like electrical insulation, capacitive sensors, and electromechanical actuators. When combined with a phase transition-induced shape memory property, the resultant bistable electroactive polymer (BSEP) opens up new applications due to the rigid-to-rigid actuation of BSEP tremendously reducing the energy consumption for device operation while providing desirable strength for external loads. This dissertation focuses on investigating insulating, electroactive, and phase transition properties of BSEP, and adapting each aspect of the properties in the pursuit of innovative devices, such as rewritable photonic paper, smart windows with whole solar spectrum modulation, and wearable pressure sensors. An ink-free rewritable photonic paper has been invented through the interdisciplinary combination of photonic crystals, shape memory and electroactive properties of BSEP. The rewritable paper consists of a ferroferric oxide-carbon (Fe3O4@C) core–shell nanoparticle (NP)-based photonic crystal embedded in a BSEP. The nanocomposite can be repeatedly triggered to change into different shapes and colors due to the z-directional deformation that is induced by an electric field. The actuated shape and color can be maintained for a long term without energy input, and the stored images can then be rewritten over 500 times without noticeable degradation. Low energy consumption and simple erasing/rewriting are features that match the benefits of conventional paper as a zero-energy and long term data storage medium, but provide the additional advantage of rewritability. With pixelated electrode arrays, user-defined information can be actuated and erased at will which has been demonstrated through a seven-segment numerical display. A smart window with wide-band light modulation is designed solely based on the phase transition property of BSEP. One component of BSEP can be switched between semicrystalline and amorphous states through cooling below or heating above its melting temperature, leading to a reversible opaque-to-transparent transition. The opacity switching property of BSEP was further improved by mixing a more hydrophilic component to induce micro-scale phase separation, which is responsible for the whole solar spectrum light modulation due to Mie scattering. The resultant smart window achieves both high solar transmittance modulation of 70.2% and high luminous transmittance modulation of 80.4% which rivals the best reported smart windows and commercial privacy glasses with the highest privacy levels. This flexible smart window can also be mounted on curved surfaces for the need of windows with arbitrary shapes. This work is the first one to report an all-solid thermochromic smart window film without the inclusion of any metal/metal oxides or liquid crystals to enable a large light modulation over the whole solar spectrum.A flexible fiber-based pressure sensor is realized by applying a dielectric layer on the outside of a TEMPO-oxidized bacterial cellulose (TOBC)/silver nanowire (AgNW) conducting fiber. The pressure sensor can detect pressures up to 134 MPa with sensitivity of 101 � 10-4 kPa-1 due to its hierarchical structure and high conductivity. The porous structure of TOBC/AgNW helps increase the thickness deformation of the sensor with applied pressure, improving the sensing ability. Small pressures of human pulse and voice vibration can be detected with this sensitive pressure sensor. A machine learning classification model was implemented to recognize human’s speech where the prediction accuracy on a test dataset is > 90%. The ultrathin fibrous sensor (53 �m) is capable of high-resolution detection, and suitable as a comfortable and fashionable thread substitute for real wearable devices.The combined properties of BSEP with the proof-of-concept developments of rewritable paper, smart windows and wearable sensors demonstrate its potential for real-world applications. And an outlook for future research and suggested improvements for commercialization are discussed in the conclusion.

Purpose: The purpose of this paper is to explore how the application of Systems Engineering tools and techniques can be applied to rapidly process and analyze the vast amounts of data present in social media in order to yield practical knowledge for Command and Control (C2) systems. Design/methodology/approach: Based upon comparative analysis of related literature a conceptual model is proposed and a Systems Engineering trade study conducted for capabilities to predict mass collective action based on social network analysis tools. Findings: The study conducted in the course of this research demonstrates significant relationships between Social Network Analysis (SNA) parameters, which describe Node Influence measured in an online social network, to reported crowd sizes at protest demonstrations. Furthermore, Network Communication variables measured in an online social network were also shown to have significant relationships to reported crowd sizes. It is concluded that while further study of larger datasets is needed, this avenue of approach is warranted and could lead to an operational online social media radar sensor system. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

This study introduces an innovative instructional method, called "pseudo peer diagram" (PPD), where students employ executive skills to compare and contrast their work with others' as a formative feedback mechanism. The focus of this study is how students compare and contrast their own diagrams with the pseudo peer diagrams as a stimulus to evaluate their own work. This is in contrast to alternative methods of learning by example which focus on how students interpret a diagram to make sense of a context. How students engage in the task of making sense of the content can provide instructors with a powerful pedagogical approach to support active learning. The learning context to examine this formative assessment strategy is a series of in-depth questions related to buoyancy forces as a system in equilibrium. Fourteen second and third year undergraduate engineering students were asked to generate free body diagrams to interpret equilibrium in the provided systems. Then PPDs were presented as a feedback mechanism to engage students in metacogitive reflection. To understand how individuals cognitively process PPDs, this study used think-aloud protocol to make students' cognition explicit. This study revealed several challenges that students encountered when they used free body diagrams to interpret system equilibrium. First, students' abilities to interpret systems or system equilibrium were greatly associated with the complexity of the tasks. They could easily comprehend and reason with classic scenarios that were frequently learned from textbooks commonly associated with basic physics, but when encountering new tasks that require the analysis of complex structures often found in engineering contexts, they were not able to perform as well. Most of them relied on shallow representations to illustrate superficial features of the tasks. And they usually neglected differentiating the finer details of the situations. Three participants requested step-by-step guidance from the experts to understand the experts' reasoning process. In addition, several students indicated their unwillingness to decompose the system and operate on the sub-systems. This study also indicated the effectiveness of PPDs in externalizing students' understanding of system equilibrium. Many students mentioned that PPDs confirmed their initial thinking, helped them notice errors and missing features, and better comprehended the contexts and scenarios. In addition, the nature of the PPDs provided multiple perspectives, from both the novice and the expert, to students. The result of this low-cost, paper-and-pencil version study has the potential to inform researchers of the rationale and guidelines to build future automatic feedback systems within the scope of first-year engineering education. This research is also relevant to engineering instructors and researchers who want to develop students' abilities to use cognitive strategies effectively. It may also interest engineering instructors who are willing to apply new instructional methods and tools to facilitate students to overcome complex design challenges. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

This paper establishes a theoretical framework that will support a qualitative study of young women who, in their second year of college, struggled with and ultimately determined a career path after first considering engineering as both a vocational choice and an identity. Establishing Baudrillard (1995) as the primary theorist for this constructivist qualitative analysis, the intersection of self-authorship as defined by Magolda (2007) and social capital as defined by Yosso (2005) will be investigated as the theoretical basis for which to begin an affective understanding. Additionally, basic literature on diverse women in STEM (Science, Technology, Engineering, and Mathematics) will be collected, critiqued, summarized and interpreted before moving on to consider the ethical implications of this work. The research data analysis will be briefly mentioned before the summarizing discussion asks how the conclusions of the analysis can best advocate for changes involving both the participants engaged in the study as well as external readers of the work. Suggested contributions to education systems, evolving knowledge data bases, and practitioners will be considered. Fiction writing as research was used to conduct this study. From the narratives, three themes emerged regarding students' understanding of themselves, their personal power and STEM as both a factor in self-authorship as well as a power in its own right: (1) Balancing the scales--social capital as help and hindrance; (2) Finding the center of self; (3) STEM's mystique. Seven suggestions for best practice in encouraging women to persist in engineering were provided. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

Link failures in wide area networks are common and cause significant data losses. Mesh-based protection schemes offer high capacity efficiency but they are slow, require complex signaling, and instable. Diversity coding is a proactive coding-based recovery technique which offers near-hitless (sub-ms) restoration with a competitive spare capacity requirement with respect to other techniques. In this thesis, an optimal algorithm is developed for pre-provisioning of the static traffic using both systematic and non-systematic diversity coding. A Mixed Integer Programming (MIP) formulation is developed for systematic diversity coding which requires many fewer integer variables and constraints than similar optimal coding-based formulations. In all scenarios, diversity coding results in smaller restoration time, higher transmission integrity, and much reduced signaling complexity than the existing techniques in the literature at the expense of slightly lower capacity efficiency than Shared Path Protection (SPP) and p-cycle protection. The drawbacks of the earlier implementations of diversity coding are the low scalability and restricted coding structure. To overcome these, a simple column generation-based design algorithm and a novel advanced diversity coding technique to achieve near-hitless recovery over large networks are proposed. The design framework consists of two parts: a main problem and sub problem. Simulation results over large networks with arbitrary topologies suggest that both the novel coding structure and the novel design algorithm lead to higher capacity efficiency for near-hitless recovery. Moreover, this thesis presents a bidirectional coding-based scheme, named Coded Path Protection (CPP). In addition to a systematic approach of building valid coding structures, this paper presents an optimal and simple capacity placement and coding group formation algorithm. The algorithm converts the sharing structure of any solution of an SPP technique into a coding structure with minimum extra capacity. Simulation results confirm that the CPP is significantly faster than both SPP and Shared Link Protection (SLP) and more capacity efficient than SLP. This thesis also investigates the dynamic provisioning of the traffic on-demand. In dynamic provisioning, an Integer Linear Programming (ILP)-based optimal algorithm covers both of the systematic and non-systematic diversity coding. The performance of proposed dynamic provisioning technique is similar to that of pre-provisioning. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

Computer facilitated Social Networking (SN) is becoming more prevalent in our society, both in our personal and professional lives. As its use grows, there is a desire to determine how it will impact an organization. If it can positively impact an organization then it is an initiative that could be embraced and leveraged for any number of business related activities from marketing to engineering. This project develops and implements a social networking treatment for an engineering organization in order to determine how it impacts the responsiveness and performance of the organization. The treatment includes an online tool, a training package, and organizational support throughout the study. The analysis of the data showed that, within the scope of this study, when an organization is provided with a social networking program and associated training and resource allocation there is no apparent impact on the organization. The tool was not used enough to itself have a significant impact on the organization however, subtle changes in the organization as a result of the overall treatment process are noticeable. Some factors that may have impacted the results were a lack of usefulness of the SN tool, the adequacy of the training was insufficient, and participants didn't see the instilled benefit in using the SN tool. This paper presents the methodology, results, conclusions, and courses of action for follow up research. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

There is an increasing demand for individuals with engineering education and skills of varying fields in everyday life. With the proper education students of high-needs schools can help meet the demand for a highly skilled and educated workforce. Researchers have assumed the supply and demand has not been met within the engineering workforce as a result of students' collegiate educational experiences, which are impacted by experiences in K-12 education. Although factors outside of the classroom contribute to the inability of universities to meet the increasing demand for the engineering workforce, most noted by researchers is the academic unpreparedness of freshman engineering students. The unpreparedness of entering freshman engineering students is a result of K-12 classroom experiences. This draws attention not only to the quality and competence of teachers present in the K-12 classroom, but the type of engineering instruction these students are receiving. This paper was an effort to systematically address one of the more direct and immediate factors impacting freshman engineering candidates, the quality of secondary engineering educators. Engineers develop new ideas using the engineering design process, which is taught at the collegiate level, and has been argued to be the best approach to teach technological literacy to all K-12 students. However, it is of importance to investigate whether technology educators have the knowledge and understanding of engineering design, how to transfer that knowledge in the classroom to students through instructional strategies, and their perception of their ability to do that. Therefore, the purpose of this study is to show the need for examining the degree to which technology and non-technology educators are implementing elements of engineering design in the curriculum. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

The purpose of this study was to explore the engineering problem finding ability of high school students at three high schools in Minnesota. Students at each of the three schools had differing backgrounds including pre-engineering coursework, traditional technology education coursework and advanced science coursework. Students were asked to find problems in two different engineering scenarios which were presented to them on a paper and pencil instrument. Responses were scored by a panel of judges based on measures of creativity (flexibility, fluency, originality and elaborateness) and analyzed based on demographic data including gender, prior coursework and school. In addition student responses were categorized and evaluated qualitatively based on school and gender of respondent. Quantitative results indicate that the most consistent predictor of creativity in engineering problem finding scenarios was the number of advanced science classes. Specific measures of creativity included other significant predictors but advanced science coursework was the most consistent across all measures and scenarios. The qualitative results showed striking differences in the responses from students at different schools. Students from schools with a pre-engineering and advanced science emphasis found similar categories of problems and had a similar view of the purview of engineers while students with a technology education background focused on a rather different set of problems and had a much narrower view of engineering. Results show clear differences in the types of problems found by students at these three high schools as well as their understanding of the scope of engineering problems. Educators need to become more aware of the importance of problem finding in engineering and better encourage the development of problem finding skills among their students. Specifically, technology education teachers may need supplemental professional development related to the scope of engineering and engineering problem finding as well as how these concepts might be infused into their curriculum and encouraged among their students. [The dissertation citations contained here are published with the permission of ProQuest LLC. Further reproduction is prohibited without permission. Copies of dissertations may be obtained by Telephone (800) 1-800-521-0600. Web page: http://www.proquest.com/en-US/products/dissertations/individuals.shtml.]

Research on paper-based microfluidic devices has grown into prosperity since 2007 when the Whitesides group in Harvard University first announced their work of qualitative bioassays on paper platform. These devices have a huge potential to be used in screening and point-of-care applications because they are easy to fabricate, simple to use, and low in cost. In this work, paper properties, wax printing, and micro-level fluid flow on paper-based materials are investigated first as preliminary study, and then a qualitative blood coagulation test device is developed utilizing traditional lateral flow platform.In order to utilize paper-based materials as test platform, various paper properties are studied to understand their behaviors with fluid present. When conducting different type of tests, different types of paper may be considered due to their unique properties. As a fabrication technique of paper device, wax printing is studied in detail to learn the printing accuracy and resolution of wax printer during device fabrication. By printing hydrophobic wax barriers on hydrophilic paper, wax printing is a very cheap, simple and fast way to fabricate microfluidic channels on paper device.Microfluidic flow behaviors of water and dextran aqueous solution with different viscosity are studied on cellulose papers and nitrocellulose membranes. Both fluids display the characteristics of Washburn flow on both types of materials. On cellulose material, fluid flows faster in narrower channels, which makes it possible to achieve flow control by manipulating channel geometry. On nitrocellulose material, fluid with smaller viscosity travels faster than that with larger viscosity, and the slope of (traveled distance)2 vs traveling time is linearly proportional to fluid viscosity on semi-log scale. This property makes it possible to anticipate fluid viscosity by measuring its traveling distance in a certain amount of time on nitrocellulose membrane.In the development of qualitative blood coagulation test device, traditional LFA structure consisting of sample pad, analytical membrane, and wick pad is utilized as diagnostic platform, and citrated rabbit blood and coagulant CaCl2 solution with different concentration are utilized to mimic human whole blood with various coagulation ability. Qualitative analysis of blood coagulation ability is performed by measuring the distance that different blood sample travels on analytical membrane. The further traveled distance indicates weaker coagulation ability, and the shorter traveled distance indicates stronger coagulation ability. A linear relationship between traveled distance and coagulation ability of blood sample is established, and whole blood coagulation ability can be anticipated by measuring its traveled distance on blood coagulation diagnostic LFA device in a certain amount of time.

This thesis focuses on the study of size-scale structural effects on paper fracture toughness. Three analyses, including tensile strength ratio, consumed energy ratio and stress intensity factor ratio were used to explore the sensitivity of paper to the propagation of cracks. The results of the comparison were utilized to focus on stress ratios for the new modified LEFM approach presented in appendix A. The modified LEFM can be used as a simple method to explore fracture toughness relative to tensile strength. Both commercial papers and handsheets were tested and analyzed for their fracture behavior using double-notched tensile specimens. The combination of experimental testing and analysis suggest that paper structure plays an important role on relative fracture toughness. The results indicate that paper towel, the least homogenous material tested, had the lowest sensitivity to notches. The differences in relative fracture toughness are related to size-scale of structural features. Relative fracture toughness varied for handsheets made under various process conditions to yield different structures. It is concluded that material relative fracture toughness increases with material heterogeneity.

Paper is an everyday product used for various reasons by the consumer. This study focuses on a low basis weight nonwoven paper substrate used as toilet paper. Paper manufacturers are always trying to increase line speed to push out more paper at the same cost and the manufacturing process this research focuses on is the embossing process. This study will focus on determining the rate dependent in-plane constitutive relations that define the mechanical behavior of the paper substrate in tension. Once the constitutive models are created they can be imported into a finite-element software package and used to study changes made to the embossing process. Experimental tests were run in order to isolate specific properties of the material. Uniaxial tension tests were run at 0.1 1/s, 4.5 1/s and 45 1/s total engineering strain rates in order to determine the rate dependent effects on the material. Stress relaxation tests were run at varying moisture contents and temperatures with the idea of determining the viscoelastic model and how moisture and temperature affect the material. Viscoelastic and viscoplastic behavior models were developed to characterize the rate dependencies in the elastic and plastic regions of the material. A generalized Maxwell model is used to model the viscoelastic region and a modified form of G’sell’s flow stress law was used in conjunction with the viscous based overstress theory (VBO) to define the viscoplastic region. The research done on this paper substrate details a method to define the rate dependent constitutive properties of any fiber network material through an experimental study.

Paper Mills use rubber covered steel rolls in the paper drying process. Often the rubber cover gets unbonded from the base and causes the paper machine to wreck. A failure detection and prediction system for the rubber covered rolls was sought as there is no standard method or system available in the industry at the moment. The rubber cover failure theory was developed after a research on the vibration data and spectra of seven actual paper mill rubber covered roll failures. This theory was then verified in a simulated paper mill run in the research and development facility using two specially designed rolls. One with a known perfect cover and the other with a rubber cover defect. An On-Line system was put together which continuously monitor these rolls and sends out alarm messages whenever any of the predefined vibration thresholds are violated. It is believed that this system will prevent any further paper machine wrecks from happening as a result of the rubber cover failure. This system will save us about $170,000.00 for each paper machine wreck avoided.

The automated banking industry, especially deposit automation, is rapidly evolving. One aspect of deposit automation includes automatic check processing modules. These are modules capable of scanning and reading a check and crediting the amount to customers's bank accounts without ever having to step inside the bank. Most of these modules are available at drive-up or walk-up Automated Teller Machines (ATMs). With the need for more functionality and the same space constraints as past designs, there are many times when low profile pinch force is required to help transport media within an ATM module.The ultimate purpose of this thesis is to provide an understanding of the unique design and analysis that goes into the creation of a pair of low profile leaf springs used for paper handling in ATMs. This involves first explaining the application in which these springs are used and the need for the design. Once the springs’ functions are defined, the parameters around which the design was created will be defined.The prototype design for these leaf springs uses mild steel which is not suited for the application in a production environment. Careful attention is required to produce consistent parts using the mild steel, because a tight tolerance band is required and because the parts are prone to deformation during handling. The shortcomings of the prototype designs are recognized, and a new design is developed and analyzed to take the place of the mild steel version of the component. This new design for the bin spring parts involves a slight modification to the geometry of the springs and a drastic change to the material selected. Finite element analysis, component measurements and functional testing are provided to support the redesign and its success for the intended application. As a result of these analyses and functional tests, a new leaf spring drive system that is both functional and manufacturable is presented.

This investigation was to compare the structural properties, of commercial available single ply paper towels, as they vary in X-Y plane. The focus was to quantify the differences in selected regions of interest, as measured by two analytical methods, non-contact Twin Laser Profilometry (TLP) and synchrotron X-ray micro-computed tomography (XRμCT). The thickness and out-of-plane deformation (OPD) distributions were mapped using a TLP and XRμCT. The XRμCT samples were further used to calculate for the mass center surface. TLP enables web structures to be mapped to a micrometer resolution over 12.5mm regions. Synchrotron X-ray microtomography method provides sub-micrometer resolution of the complete volumetric structure (1.4mm x 1.4mm x thickness (μm)) for the imaged region. The features of individual fibers are revealed by XRμCT method, so that the true surface geometry may be quantified.

A study of the acoustic emissions characteristics of handsheet made under diverse wet-pressures is presented. It is believed that the acoustic emissions technique describes the inelastic deformation, damage, and fracture characteristics of paper well. It is concluded that there exists an optimum wet-pressure at which a paper with better mechanical properties such as high strength and optimum ductility and best fracture toughness may be manufactured. It is suggested here that beyond this “optimum” wet-pressure it is possible to over-press the handsheets during the manufacturing stage. This causes internal damage in the microstructure of the fibrils and instigates the evolution of inherent flaws or defects in the paper. These defects or flaws become active during the tensile loading of the paper and extend or propagate under loading, thus reducing the overall macroscopic deformability, compliance, and ductility of paper. Alternatively, below this optimum wet-pressure the paper does not develop its full potential strength. The results of the acoustic emissions testing have consistently suggested that fracture resistance toughness, and therefore, failure in paper is a strain-related phenomenon. As acoustic emission is a deformation (or strain) sensitive event, a new definition for toughness of paper is introduced, which is equal to the measured area under the cumulative hit distribution curve. The exact, asymptotic, as well as simplified approximate expressions have been derived, which may be used evaluate the acoustic emissions toughness of paper. The results of the acoustic emissions testing indicated that based upon this definition of "AE toughness," the toughness of paper was highest for papers made under the "optimum wet-pressure" condition. It was also suggested that Tensile Energy Absorption (TEA), a measure of the area under the stress-strain curve, may not be a suitable measure for the fracture toughness of paper. This conclusion is more substantiated by the fact that fracture of paper is a strain[1]related phenomenon, and therefore, the fracture toughness should not be biased by stress.

A legislative authority empowered to protect Srilanka's environment, operating similarly to the Environmental Protection Agency of the U.S., is needed, along with wastewater treatment. Wastewater parameters of importance in treatment are BOD, COD, total suspended solids, settleable solids, pH, colour, turbidity, ammonia or nitrate nitrogen, heavy metals, sulfides, phosphates, and phenols. Methods of industrial waste treatment vary depending on the climatic conditions, the industry, raw materials, and process adopted. Textile and pulp and paper industries exist in Srilanka and have very high pollution potential. Methods of treatment to finally generate reasonably good quality effluent are available. Processing of effluents from these type industries together with municipal sewage is feasible and economical. Due to the complex nature of the composition of industrial wastes, a final decision could only be made after a thorough investigation of the industrial complexes, the methodology used, and pilot plant studies.

Unmanned aerial vehicle (UAV) swarms have the potential to be useful in numerous applications due to their versatility and ability to operate without human intervention. However, this promising technology still requires further investigation, research, and testing before UAV swarms can be implemented extensively. The level of human intervention needed to control the system determines the differing levels of autonomy for UAV swarms. For swarms to become more independent, efficient algorithms for task and path planning are essential. In addition, accurate communication is essential for swarms to be able to coordinate and accomplish tasks successfully. This paper seeks to provide a review on the architecture, communication, applications, and challenges associated with UAV swarms. Furthermore, this paper discusses the types of communication that have been used or proposed for UAV swarms. Lastly, this paper provides a review of the potential applications of UAV swarms, as well as the research issues which still exist surrounding this technology.

Coke drums are large pressure vessels used in the oil refining process, which generate lightweight oil products and solid cokes as a byproduct from the heavy residual oil. Coke drums are critical units in the delayed coking process and often undergo severe thermo-mechanical loadings that cause plastic deformation in the vessels. The accumulative damage in coke drums over operation cycles leads to low-cycle fatigue failure that significantly reduces the lifetime of coke drums. Many factors can contribute to the low-cycle fatigue damage in coke drums, including design, fabrication, operation, and repair. One of the inherent reasons is the thermal and mechanical incompatibility between the base metal and weld metal, as low-cycle fatigue damages are frequently observed adjacent to the weld seams. The structural integrity is significantly compromised at a bulging or cracking region, so coke drum repair is required before continuing the operation. Welding repair has been widely adopted in industry to restore the structural integrity of damaged regions. However, the repaired regions are also susceptible to subsequent failures due to welding defects and mechanical incompatibility.A careful selection of filler metal and the welding process is critical to improve the efficacy of welding repair. To address the issue of selecting the optimal filler metal and welding process for coke drum repair, a study regarding coke drum welding repair was initiated in the Manufacturing & Materials Joining Innovation Center (MA2JIC) at OSU in the year of 2016. In Phase-I, a novel isothermal low-cycle fatigue (ILCF) testing approach was developed using the Gleeble® thermo-mechanical simulator, and a wide range of filler metals and welding processes were evaluated using this technique. The project entered Phase II in the year 2019. The Phase-II study continues Phase-I efforts on filler metal selection based on low-cycle fatigue evaluation and expands the materials selection scope to coke drum fabrication. In addition, fundamental analysis of the low-cycle fatigue performance of coke drum base materials and welded joints was implemented through mechanical testing, materials characterization, in situ testing, and finite element analysis. This document covers the achievements made in Phase II and includes a summary of key findings in both Phase I and Phase II.The document consists of 11 chapters. Chapter 1 discusses the motivation and objectives of Phase II study, and Chapter 2 presents the background of this work. The industrial background of cokedrum is first discussed in Section 2.2 and followed by the discussions of a literature review in low-cycle fatigue testing approaches, materials performance, and weld simulation. Chapter 3 presents the low-cycle fatigue testing results of C-0.5Mo steel and a comparison with the 1.25Cr-0.5Mo steel results (Phase I) in terms of low-cycle fatigue performance. Chapter 4 shows the low-cycle fatigue evaluation of Ni-steel dissimilar joints and failure analysis. The chapter is constructed by three conference proceeding papers published regarding the topic. Chapter 5 evaluates the cyclic deformation of a dissimilar welded joint, in which the weld failure predominantly occurred in the weld metal region adjacent to the fusion boundary. Part of the contents in Chapter 5 overlap those in Section 4.1 and Section 4.2, but Chapter 5 presents a more in-depth analysis of the failure mechanism using the advanced characterization and the in-situ testing approach. Chapter 6 presents a published paper regarding cyclic deformation and strain localization in ferritic-pearlitic C-0.5Mo steel. This chapter aims at fundamentally understanding the impact of the ferritic-pearlitic microstructure on the cyclic behavior observed in Chapter 3. Chapter 7 introduces the measurement of local mechanical performance in similar and dissimilar welded joints using the digital image correlation technique. Chapter 8 introduces a novel optimization algorithm for cyclic hardening parameters, which are obtained from the isothermal low-cycle fatigue testing results. Chapter 9 presents a summary of the achievements in Phase I and Phase II regarding the selection of the material for coke drum fabrication and welding repair. Chapter 10 and 11 presents the major conclusions and future work for the study.

This paper introduces low-velocity impacts (LVI), presents a concept for evaluating them, tests various materials for proof-of-concept, and discusses how the machine could be used in future university projects as well as how it could be improved. The paper begins by defining low-velocity impacts and describing the factors that influence them. The second topic is the iterative design process involved with making an impact machine so that accurate results can be obtained. In the third section, some of the challenges and opportunities associated with the concept of low velocity impacts with a variety of tests conducted on the machine and with different materials. A summary of the design and results of the study is presented at the end of the paper, followed by some suggestions for further research and improvements that could be made.

This paper focuses on designing, modeling, and controlling a suspension system for a Baja SAE vehicle with an integrated semi-active suspension damping system. The main goals in order to optimize performance are to maximize vehicle speed through various inputs and minimize stress on critical components. Sensor technology including inertial measurement units (IMU), strain gauges, and hall effects are used to measure vehicle parameters throughout road inputs. This data is then analyzed using machine learning techniques to determine the most influential parameters in maximizing speed and minimizing stress with the fastest reaction time. Once these most influential and implementable parameters are determined to be pitch and roll, they are used to create a simplified on car optimization algorithm to improve vehicle performance, as validated by data collected on the vehicle.

A primary concern of any device that uses prisms is the fact that prisms are inherentlydispersive. Risley prism optical steering devices are made of two or more prisms rotatedabout a common axis. Dispersion is the fact that any homogeneous glass will refract eachwavelength differently because the index of refraction of a material is not constant acrosswavelength. Risley prisms have other positives that broadband systems would like to makeadvantage of, and dispersion is their primary roadblock.This paper will investigate two possible solutions to the issue of dispersion in prisms.Examples will be generated for the visible, short-wave infrared, mid-wave infrared, andlong-wave infrared broadbands of each dispersion removal method. Lastly, a real worldprism using one of these methods was tested.

This research details the development of a cutting-edge Low Noise Amplifier (LNA) using advanced 28nm CMOS technology. The study focuses on achieving optimal performance in high-frequency wireless communication systems. The LNA design showcases a significant gain of 40.39 dB at 6.31 GHz and an impressive noise figure of 6.68 dB at 6.31 GHz. The total area of the chip is 0.576 mm2. The methodology includes utilizing a common-stage LNA configuration with inductive source degeneration and cascade structures to enhance gain and noise performance. Special emphasis is placed on impedance matching, with a meticulous design of input and output networks to minimize signal loss and noise addition. The paper also explores key aspects of LNA design, such as transistor sizing, stability, and linearity. Stability is rigorously analyzed using S-parameters, ensuring the LNA's resistance to self-oscillations. Linearity is addressed through measures like the Third-Order Intercept Point (IIP3), ensuring signal integrity in the presence of strong interfering signals.

Infrastructure such as transportation networks improves the condition of everyday lives by facilitating public services and systems necessary for economic activity and growth. However, constructing and maintaining transportation infrastructure poses safety hazards and risks to those working at the sharp end, leading to serious injuries and fatalities. Therefore, the identification of hazards and managing the risks they create is integral towards continually improving safety levels in Infrastructure Management. This work seeks to fully understand this problem and highlight past, present and future issues concerning safety in a comprehensive literature review. A decision support tool is proposed to improve the safety of transportation workers by facilitating hazard identification and management of associated control measures. This Tool facilitates the extraction of safety knowledge from real paper-based safety documents, capturing existing worker’s knowledge and experiences from industrial ‘corporate memory’. The Tool suggests the most appropriate control measures for new scenarios based on existing knowledge from previous work tasks. This is achieved by classifying work tasks using a new method based on unilateral UK legislation (Reporting of Injuries, Diseases and Dangerous Occurrences (1995) Regulations) and the innovative use of Artificial Intelligence method Case Based Reasoning. Case Based Reasoning (CBR) allows transparency in the Tool processes and has many benefits over other safety tools which may suffer from ‘black box’ stigmatism. The Tool is populated with knowledge extracted from a real transportation project and is hosted via the internet (www. Total-Safety.com). The end product of the Tool is the generation of bespoke method statements detailing appropriate control measures. These generated paper documents are shown to have financial and quality control benefits over traditional method statements. The Tool has undergone testing and analysis and is shown to be robust. Finally, the overall conclusions and opportunities for further research are presented and progress of the work against each of the five research objectives is assessed.

This paper presents the results of an effort to use geophysical measurements such as seismic wave velocities and electrical resistivities to calculate airfield design parameters. The study converts all geophysical measurements to equivalent California Bearing Ratio (CBR) values, comparing CBR values estimated from DCP penetration resistance with CBR values estimated from shear wave velocity and electrical resistivity values. Relationships linking the geophysical measurements to CBR estimates were established using laboratory data and applied to field in-situ measurements. The elastic modulus (E) is the stiffness parameter involved in predicting soil strength and stiffness. This research aims to relate electrical conductivity and modulus by using a box test. A sigmoidal model was proposed for the prediction of elastic modulus as a function of conductivity, which performed well with high-strength soil. Soil tests from two different source locations were considered at different moisture contents, with a total of eight tests analyzed. The results show that elastic modulus values estimated from both shear wave velocity and DCP measurements tend to perform better at low conductivity and higher stiffness soil types. However, the elastic modulus from the proposed model does not match well with the DCP or shear wave velocity data when applied a field site located in Rouen, France. Overall, this study demonstrates the viability of using geophysical methods to assess airfield suitability and improve the accuracy of soil assessment in airfield design.

The surge in demand for hydrogen (H2) across diverse sectors, including clean energy transportationand chemical synthesis, underscores the need for a thorough investigation into H2 production dynamics and the development of effective controllers for industrial applications. This paper focuses on an electrically heated steam methane reforming (SMR) process for H2 production, offering advantages such as enhanced environmental sustainability, compactness, efficiency, and controllability compared to conventional reforming methods. Electric heating of the entire system allows for adjustments in current to control reactor temperature, thereby impacting hydrogen production rates. However, accurately modeling hydrogen production dynamics presents a formidable challenge, as complex models with high precision are computationally unsuitable for real-time control integration. Considering these factors, an accurate and efficient first-principlesbased lumped-parameter model is developed to provide a dependable estimation of hydrogen production in an electrically-heated steam methane reformer. This model is validated experimentally and then utilized in a model predictive controller (MPC). To obtain the necessary state estimate information for the MPC, an extended Luenberger observer (ELO) method is employed to estimate state variables from limited, infrequent and delayed measurements of gas-phase reactor outlet stream and frequent measurements of the reactor temperature. Simulation comparisons with a proportional-integral (PI) controller reveal a much faster response in achieving the desired H2 production rate under the estimation-based MPC. Additionally, the simulations demonstrate the robustness of the controller to process variability such as a decrease in catalyst activation energy, commonly encountered in the SMR process, highlighting its effectiveness in maintaining stable operation under varying process conditions.

Engineers are needed more than ever to sustain our current life and maximize the best possible life for our future. From our everyday present lives, engineers work on powering our markets, offices, and homes to designing computer software. From what our future holds, engineers can develop efficient humanoid robotic systems to conduct surgical procedures, build renewable energy buildings and transportation sources, and predict meaningful political, medical, and financial information based on prior big data. Yet, in the United States, the field of engineering neither attracts nor maintains college students who were originally interested in pursuing it, particularly for minoritized students (Beering, 2007; National Science Foundation, 2021). Increasing and diversifying the number of engineers will contribute not only to better current and future living standards, but also bring new perspectives to solve the problems the nation faces. This dissertation research aims to address the critical issue of college students becoming uninterested or disengaged in engineering through YouTube videos to promote choice and persistence.The dissertation consists of three separate, but connected papers that examine undergraduates’ choice and persistence in engineering using an alternative methodology of YouTube videos. Paper 1 focuses on engineering college students’ career values and the extent to which the discussion of their careers is associated with career values. There are two studies within this paper. The first study investigates students’ agentic (i.e., the importance of doing something in service of the self) and communal (i.e., the importance of doing something in service of others) career value themes in their written post-graduation responses after watching a YouTube video. I found career, personal development, and financial gains agentic career value themes as well as helping others and being family- oriented communal career value themes. The second study uses those career value themes to match achievement-related and interpersonal word categories to surveyed career values. I found significant associations between students’ word usage on their career and surveyed career values. Paper 2 examines transfer engineering undergraduates’ experiences filming engineering advice-related YouTube videos to community college students, in which we predicted that students experience the saying-is-believing effect. The saying-is-believing effect refers to how individuals are more likely to internalize a message if they advocate for it (Higgins & Rholes, 1978). This study identifies for important college students’ affective, cognitive, and behavioral engagement themes during their experiences creating the YouTube videos, in order to differentiate the different levels of the saying-is- believing effect. I found that students do differ in the extent to which they experience the saying-is-believing effect based on the different components of engagement. In particular, students’ positive affective experiences from creating YouTube videos may be the starting point to experiencing the saying-is-believing effect. Paper 3 takes a different perspective of the motivational intervention by focusing on the engineering community college students who watched the YouTube videos rather than those who filmed the YouTube videos. Students were able to choose from a library of videos from a diverse group of engineering transfer undergraduates. This study investigates the difference in engineering community college students’ course grades and subsequent engineering course enrollment between those who participated and those who did not participate in the intervention. I found that students who participated in the role model intervention leveraging YouTube had higher course grades and subsequent course enrollments in engineering compared to those who did not participate in the intervention.Each of the three papers: (a) provides a greater understanding on how to support engineering college students’ choice and persistence; and (b) focuses on using YouTube videos as an alternative method to gain a more comprehensive picture on engineering undergraduates’ motivation. Using YouTube videos to understand students’ perceptions can help participants answer in a way that would minimize predetermined item choices and researchers’ expectations. This methodology can aid researchers and practitioners investigate engineering college students in a more naturalistic way. Incorporating a wide selection (or library) of YouTube videos from minoritized engineering college students can optimize the motivation of others who similarly identify, which can thus, increase the diversity in the labor force market.

Duplex stainless steels (DSS) are extensively used in heavy industry, such as Oil and gas, pulp and paper, and chemical, due to their remarkable corrosion resistance, yield strength, and toughness. The most corrosion-resistant DSS subgroups, super duplex stainless steels (SDSS) with Pitting Resistance Equivalent numbers (PREn) of 40-48, and the hyper duplex stainless steels (HDSS) with a PREn over 48, are highly alloyed. Additions of Cr and Mo provide better PREn but also promote intermetallic phases such as the chi and sigma phases. These intermetallics form when the material is exposed to temperatures between 600oC – 1100oC. It is known that even small volumetric fractions of the sigma phase severely reduce the material’s corrosion resistance and mechanical performance.A dedicated study on sigma phase formation kinetics was developed to control sigma phase presence in these specific alloys. A field studied but not yet completely connected between scientific research and industrial applications. Fundamental aspects of sigma phase kinetics were analyzed, computationally modeled, and experimentally validated. As a result of these efforts, the interface area per unit of volume was revealed as a critical microstructure factor for the sigma phase kinetics. The resultant model’s efficacy was further evaluated by building GTAW cladded mockups, and investigation into this material’s mechanical and corrosion performance further expanded on the impacts of the sigma phase.A Gleeble® system was used to develop experimental time temperature transformation (TTT) maps on SDSS and HDSS filler metals for sigma phase precipitation kinetics. Classical nucleation theory was then implemented on the CALPHAD-based kinetics model. In this model, the interfacial energy and nucleation sites were identified as the kinetics parameters to adjust the model based on experimental data. The sigma phase kinetics continuous cooling transformation CCT curves were calculated using the additive rule. A minimum cooling rate threshold of 4oC/s was found for sigma phase formation.Validation for application was developed through GTAW cladded mockups. While the sigma phase kinetics were equivalent in both filler metals, the corrosion and mechanical performance obtained from HDSS suggest it as a superior material. However, the sigma phase has proven to remarkably reduce the HDSS toughness. Thus, a sigmoidal behavior mechanism describing the sigma phase effect on toughness performance is proposed.Finally, an ICME python framework was developed to automate and extend the sigma phase kinetics analysis to other chemical compositions of highly alloyed DSS based on the development obtained in this research. The framework combines CALPHAD equilibrium analysis, CALPHAD-based kinetics, JMAK kinetics, and FEA thermal modeling to result in sigma phase volumetric presence as a function of the thermal history and allow optimization to performance or productivity.

Resistive heating of nanocomposite material is proposed for use in many applications because of its light weight and low current requirements. When the nanocomposites are resistively heated, thermal stresses starts arising in it due to mismatch of CTE between the fiber and matrix of the nanocomposite. A nanocomposite material can withstand only limited thermal stress when it is resistively heated. If the thermal load is too high, or combined with other external loads, the nanocomposite can fail by means of delamination, crack formation, warpage and other related modes. Hence, studying the thermal stress that develops in nanocomposites upon resistive heating will help in preventing otherwise unanticipated failures. The objective of this effort was to develop and experimentally validate a Finite Element Method model for evaluation of the thermal stress arising in nanocomposite material upon resistive heating. In order to fill the technology gap of predicting thermal stress in resistively heated nanofiber composites, a finite element method (FEM) model was created. This model was created using ABAQUS® software. To verify the results of the model, the experimental method of hole-drilling was adopted. The nanocomposite considered for the research were a carbon/glass hybrid with epoxy resin and a glass/epoxy composite reinforced with CNT Buckypaper. The experiment was based on the principle of redistribution of stress when the hole is drilled in the composite and the relieved strain is measured by a strain gage rosette. The strain release corresponds to the thermal stress that was present before the drilling the hole. The thermal stress results of hole-drilling method were compared with the FEM model result, validating the model and analysis results. The verified FEM model can be used to predict thermal stresses arising in nanocomposites and preventing failure when the nanocomposite is resistive heated and externally loaded.

On the surface, creativity seems to be an attainable, easy-to-master construct. However, ‎when diving into the literature, the observer will realize that creativity is a complex, ‎multifaceted, highly debatable phenomenon with many definitions, models, and factors ‎attached to it. Given the complexity and the multi-disciplinary nature of creativity, this ‎dissertation took the systems thinking approach to organize its associated landscape and ‎confirm the effect of some factors on engineers. The mission was accomplished by first ‎proposing a data-driven definition for creativity based on the analysis of 166 definitions. ‎Second, a classification of the vast number of models describing creativity was proposed ‎based on the analysis of tens of creativity related papers. The classification resulted in ‎five categories: Level Models, Thematic Models, Process Models, Mental Models, and ‎Ecological Models. Third, a nested model for the five creativity levels: mini-c creativity, ‎little-c creativity, ed-c creativity, Pro-c creativity, and Big-C creativity was proposed based ‎on an extended analysis of four creativity level models: 2C Model, 3C Model, 4C Model, ‎and 5C Model. Fourth, an enhanced thematic model for the seven strands of creativity: ‎person, process, product, press, measure, persuasion, and potential was proposed based on ‎the ‎analysis of five creativity thematic models: 3PM Model, Rhodes 4P Model, Simonton ‎‎4P ‎Model, 5P Model, and 6P Model. Fifth, a simplified process model for creativity ‎consisting of three ‎interconnected steps: problem understanding, divergent thinking and ‎convergent ‎thinking was proposed based on an extended analysis of two creativity process ‎models: Wallas Model and Osborn-Parnes Creative Problem-Solving Model and an overall ‎analysis of six other models. Sixth, a classification of the vast number of factors affecting ‎creativity was proposed based on ‎the analysis of tens of creativity related papers. The ‎classification resulted in three categories: personal ‎characteristics, environmental ‎characteristics, and approaches and tools. Seventh, an ecological model for creativity ‎based on the classification suggested ‎for creativity models as well as the classification ‎suggested for creativity ‎factors was proposed. Eighth, the relationship between a set of ‎personal characteristics (biological ‎factors, knowledge and experience, personality, creative ‎self-efficacy, and creative ‎potential), task engagement, and creative performance was ‎studied to confirm their effects in the field of engineering. Ninth, the effect of near and ‎far cues on the creative performance of engineers was investigated both behaviorally and ‎neurologically and no statistically significant differences were detected.‎

The persistent demand for flexible and wearable electronic components in healthcare, aerospace, media, and transit applications has led to a significant shift from traditional electronics processes to printed electronics. Printed electronics are anticipated to establish itself as the industry's dominant force due to their enhanced flexibility, rapid prototyping capabilities, and seamless integration with everyday objects. They are cost-effective and have the scalable option for large-scale production because additive manufacturing techniques are used. Among the various printing methods available, inkjet printing has recently gained popularity for printing electronics, especially capacitors that require precise and complex structures on different substrates. Inkjet printing relies on micro dispensing additive technology, where liquid phase materials are dispensed using the drop on demand (DOD) technique with conductive nanoparticle inks. Researchers have made several attempts to fabricate fully inkjet-printed composite capacitors and have discovered that the permittivity value of the composite increases compared to a polymer. This suggests that using composites as the dielectric material in a capacitor can potentially increase the capacitance value. However, despite the discussion on various composite dielectric materials, there is a scarcity of information on the use of BaTiO3/SU-8 dielectric materials for capacitor applications. To address this gap, the objective of this study is to formulate BaTiO3/SU-8 ink suitable for inkjet printing and develop a printing process for layered metal insulator metal (MIM) structures. The formulated BaTiO3/SU-8 ink is employed to print the dielectric material, while nano silver ink is used for the two electrodes, enabling the fabrication of the capacitor in a single step. The study takes into account volume and speed jetting parameters as well as waveform to achieve optimal and uniform liquid phase material inkjet printing on the substrates. The thickness of the printed layers is measured using a profilometer, and the sheet resistance of the inkjet printed nano silver conductive ink is evaluated using a four-point probe. Furthermore, the dielectric properties of the printed composite are characterized by measuring the capacitance value. The main goal of this paper is to provide insights into the formulation of BaTiO3/SU-8 dielectric materials and understand the processes involved in the fabrication of a full inkjet printed composite MIM capacitor. Additionally, the experimental results will be compared with theoretical models of BaTiO3/SU-8 dielectric developed by our research group. The successful development of inkjet printed composite MIM capacitors using BaTiO3/SU-8 dielectric materials has the potential to revolutionize the field of printed electronics. The ability to print capacitors with higher capacitance values and complex structures on flexible substrates opens up new possibilities for the integration of electronics into various applications. This research makes a valuable contribution to the expanding knowledge base in the field of inkjet printing for electronics, laying the foundation for future advancements in flexible and wearable electronic devices.

Imaging technology is a growing field that provides solutions in many areas from manufacturing to agriculture. Through previous research, imaging technologies have been studied in livestock farming to monitor the animal’s health and welfare in the production process. However, the feedlot industry is still behind in validating the feasibility to use some of these technologies nor to adopt such technologies to address challenges the industry is facing, such as lack of skilled labor.This work proposes using novel imaging methods to identify feed types and estimate the amount of feed remaining in a typical Midwestern feedlot feed bunk. These methods have promising potential to provide alternative tools to feedlot operations to alleviate labor requirements for tasks like bunk calling, feed sourcing, and feed mixing. This approach, if successful, provides an alternative option that allows existing systems to incorporate these methods into their framework to accurately perform daily tasks.The main contribution of this work is to leverage imaging technologies, specifically, depth imaging and machine learning techniques to build and validate models that can be used in the feedlot production systems in the Midwestern U.S. To date, several studies have explored the use of imaging technologies and machine learning to monitor individual cow intake in dairy production, but there is limited research body comprehensively conducted to explore these technologies for feedlot applications.The proposed methods were used to collect imagery data for eleven common feedlot ingredients and seven diets. Collected images were processed (a) to estimate the weights of residual feed in the bunk, (b) to evaluate the accuracy of depth cameras in estimating residual feed, (c) to characterize the different feed textures, and (d) to classify feed textures using machine learning techniques. Regression models using pixel transformation were developed to correlate image-model-estimated and the scale-measured feed weights, whereas texture analysis techniques and residual neural network model in 10 classes were used to identify the individual ingredients. Methodologies and results are presented in this thesis as a paper format. The major findings indicate that using low-cost depth cameras and machine learning techniques is promising in the development of alternative tools to estimate the amount of residual feed in concrete bunks and identify individual feed ingredients commonly used in commercial feedlots in the U.S. Advisor: Yijie Xiong

With the increasing prevalence of electronic equipment worldwide, there is also a decrease in the size of the components on their printed circuit boards (PCBs), leading to an increase in the density of these components. A significant amount of failure in electronic equipment is vibration fatigue of solder joints and their attachments. However, the complexity of these PCBs and their components has made finite element modeling (FEM) more complex, adding considerable time to create and analyze a model. This paper aims to provide a literature review for the vibration fatigue of leaded solder components, create a test setup, and validate an analytical solder joint stress model. The literature review provides a walkthrough on modeling PCBs and their components using FEMs and analytical models, fatigue modeling methodology, and fatigue testing data and highlights gaps in the literature. This review was important to compile due to the limited data and the rigor required to find it all when searching. With this literature review collected, testing was to be completed using an analytical model highlighted. Therefore, a setup and procedure have been developed to test the vibration fatigue of leaded solder attachments. The setup combines a test specimen, specimen mounting head, and preliminary model correlation between the test specimen and FEM. Using initial model correlations, an analytical solder joints stress model, and fatigue curves from literature, a vibration fatigue life prediction was made for the test specimen, and tests were run. However, the results were inconclusive and further testing is deemed necessary. Suggestions have been made, such as picking other analytical models to test, modifying the test setup, and increasing the fidelity of local areas in the FEM.

Unintentional releases of hazardous gases have led to significant injuries and fatalities in severe cases. Field tests can be used to release hazardous gases to document and evaluate the behavior of the gases. Chlorine is an especially hazardous gas due to its toxicity. The Jack Rabbit II Phase I field tests released chlorine within a mock urban environment (MUE) consisting of Conex containers arranged in rows to simulate buildings and streets. The number of field tests is limited by both expense and time. Simulation of a field test using a wind tunnel model can provide additional data and opportunity for study of relevant phenomena at reduced cost. This study focused on Phase I of the Jack Rabbit II trials which consisted of five vertically downward chlorine releases into the MUE. The chlorine deflected horizontally off the underlying concrete pad to spread radially outward into the MUE. In the wind tunnel model, the field releases were simulated by releasing a gas mixture of theater fog, sulfur hexafluoride, carbon dioxide, and air into the 1:50 scale tunnel model through an area source. A polycarbonate disk was positioned above the area source to deflect the vertically upward tunnel release into a radially spreading horizontal wall jet similar to what was observed in the field tests. The flow rate, composition, and wall jet initial height are source gas parameters that must be determined to model the field tests. Jack Rabbit II Trial 4 was used to determine the source gas parameters by adjusting each parameter and comparing the gas behavior of the tunnel model to the behavior of the field trial. Once the video record parameters were determined, the parameters were validated by comparison to Jack Rabbit II Trial 5. Jack Rabbit II Trial 3 had inconsistent wind data to model with confidence in the wind tunnel. The tunnel model was used to estimate the wind direction during Trial 3 by simulating different wind directions and comparing release behavior of the tunnel releases and field test. The tunnel model was further used to determine the maximum upwind extent of the field chlorine release if the MUE offered the least upwind resistance by changing the wind direction. The release method and parameters determined in this study were used in further tunnel model simulations to measure the concentration of the release gas in instrument locations with the MUE. The release method was further used to study the wind direction within the MUE at specific locations and planes. Additional videos are included along with this paper to demonstrate the tunnel model simulating the field releases. The videos show a comparison of the field release and the similar behavior of the tunnel release. Each of the three videos is labeled with the trial number of the field release that the wind tunnel model is simulating: Flow Visualization of Jack Rabbit II Trial 3, 4, and 5.

Software models are used to analyze and understand the properties of the system, providing stakeholders with an overview of how the system should work before actually implementing it. Such models are usually created informally, such as drawing sketches on a whiteboard or paper, especially during the early design phase, because these methods foster communication and collaboration among stakeholders. However, these informal sketches must be formalized to be useful in later applications, such as analysis, code generation, and documentation. This formalization process is often tedious, error-prone, and time-consuming. In an effort to avoid recreating formal models from scratch, this thesis presents SkeMo, a sketch-based software modeling tool. SkeMo is built on a CNN-based image classifier using 3000 input sketches of class diagram components and integrated into the functionality of an existing web-based model editor, the Instructional Modeling Language (IML), with a newly implemented touch interface. SkeMo was evaluated using a ten-fold cross-validation to assess the image classifier and through a user study involving 20 participants to collect metrics and feedback. The results demonstrate the promising potential of sketch-based modeling as an intuitive and efficient modeling practice, allowing users to quickly and easily create models to design complex software systems.

Fundamental understanding of crumpled graphene and its optical properties are currently lacking. This paper addresses the gap in current literature by characterizing two hierarchical graphene systems: biaxially-strained randomly crumpled graphene (BRCG) and gold particle coated periodically crumpled graphene (GP-coated PCG), through rigorous coupled-wave analysis (RCWA) and finite-difference time-domain (FDTD) computations. In BRCG, the structure is primarily characterized by its correlation length (ξ) and root-mean-square amplitude (α), which are taken as the average value over the entire simulation space, as well as the film thickness (δ). In GP-coated PCG, the periodic crumple structure is characterized by its amplitude (A) and pitch (P) as well as the radius (r) and separation (λ) of gold particles. The results show by decreasing the ξ of BRCG from 1.5 to 0.25 μm, the spectral average absorbance in the ultraviolet to near-infrared (0.2–2 μm) region increased from 0.44 to 0.75 while reflectivity was lowered from 0.52 to 0.19. Increasing α from 0.25 and 1.5 μm, the spectral average absorbance increased from 0.38 and 0.75 while reflectivity was lowered from 0.59 to 0.19. The rise in absorbance observed with decreasing ξ and increasing α is attributed to the resulting geometrically induced enhancement in internal ix scattering between and within adjacent crumples. The simultaneous reduction in reflectivity is due to the amplification of interference effects and the lowering of specular reflection as surface roughness is increased. By decreasing δ from 3.5 to 0.35 nm, average absorbance was lowered from 0.45 to 0.31 due to a shorter optical length which diminishes internal scattering. Average reflectivity also increased from 0.51 to 0.66 and is driven by the reduction in absorbance. In GP coated PCG, decreasing the P from 1 to 0.14 μm led to an increase in average solar absorbance (Asolar) in the UV-NIR (0.05–1 μm) region from near-zero to 0.14 due to the associated enhancement in electric field confinement and plasmonic resonance. Concurrently, the average solar transmittance (Tsolar) in the same region decreased from 0.74 to 0.55 due to the reduced exposure of underlying transmissive graphene while the average solar reflectivity (Rsolar) is marginally improved from near-zero to 0.05 due to the diminished separation between reflective gold particles. The same mechanisms are applied to explain the changes in optical properties with varying A. Decreasing A from 0.2 to 0.025 μm. Asolar increased from 0.07 to 0.14, Tsolar decreased from 0.67 to 0.55, and Rsolar was again marginally improved from near-zero to 0.05. In the mid infrared (MIR, 1–20 μm), all optical signals were shifted along the wavelength axis due to Bragg diffraction without notable changes in their magnitude. Enlarging r from roughly 4.2 to 67 nm increased Asolar from near-zero to 0.15 due to the enhanced presence of gold particles which contribute to electric field (E-field) confinement and plasmonic resonance effects. The enlarged extinction cross-section of gold particles with increasing r also contributes to the rise in absorbance. Rsolar also increased from near-zero to 0.09 and Tsolar dropped from 0.74 to 0.49 due to the increased cross-section of gold particles and decreased exposure of underlying graphene, respectively. Changing λ from 0.2 to 0.05 μm, Asolar increased from 0.01 to 0.06 due to the enhancement in E-field confinement enabled by the closer proximity of gold particles. This was x accompanied by a reduction in Tsolar from 0.73 to 0.67 and a marginal improvement in Rsolar from near-zero to 0.01, attributed to the same mechanism discussed above. Marginal changes with varying particle radius and separation were observed in the MIR. Thermal analysis further demonstrates enhanced radiative heating and cooling through precisely controlling the structures’ solar absorptivity and infrared emissivity. This paper presents two approaches to creating hierarchical graphene systems through varying either the surface geometry of BRCG or nanoparticle dimensions of GP-coated PCG, and subsequently tune their optical properties from the UV-NIR to MIR region to enable more effective thermal radiation control.

The objective of this research project was to replicate the dynamic behavior of a truck-tank trailer combination vehicle using representative dimensions, properties, and inertias of the trailer/fluid ballast combination. A literature review was completed describing techniques for modeling fluids and fluid-container interactions using finite element analysis. Various fluid modeling techniques were identified, and parameters associated with those models were archived. Next, researchers utilized the tank geometry of the elliptical straight-frame 5949 trailer produced by LBT Inc. to generate a finite element mesh using finite element analysis preprocessors HyperMesh and LS PrePost. Material properties were taken from reference guides, research papers, and specifications from LBT, a tank trailer manufacturer. Component constraints were added to the model to mimic fasteners such as bolts and nuts. Contacts were also added to allow the tank to impact external features, as well as to allow tank components to interact with each other during dynamic events. Different techniques were employed to generate fluid meshes to reside within the interior tank structure. Next, preliminary properties for the fluids were generated using reference materials from published papers. Finally, fluid components were implemented into tank-trailer model. The minimum barrier height to contain a tractor-tank vehicle was determined to be 62 in. for a rigid, vertical-faced barrier by a barrier height analysis done through LS-DYNA computer simulation. Recommendations for how to improve the tank-trailer model were presented. Advisor: Cody S. Stolle

This paper aims to explore the application of small-scale desalination systems to provide clean water in the wake of marine natural disasters. A lack of clean water is a devastating impact of many natural disasters. Desalination technologies, both thermal and membrane, show potential for being scaled down and self-powered by renewable energy. Desalination can transform ocean water and contaminated drinking water with a high salt content into drinkable, usable water. While these techniques are not perfected, and the solution to a need for clean water is multifaceted, desalination shows potential. Through further research and ever-advancing technology, small-scale desalination could develop into a life-saving solution for those in need of clean water.

Currently Arkansas requires a layer of asphalt as the main bond-breaker over cement treated base for rigid pavement design. The study presented in this paper aims to replicate the results from previous research which demonstrated the bond-breaker properties of concrete curing compounds and geotextiles. Bond-breakers are materials applied to the surface of stabilized bases to reduce the interaction between the base and a pavement cement concrete layer. The excessive interaction between these two layers can lead to cracking in the overlay and reduction of the serviceability life of concrete. The curing compound was applied in a single application (SA, 200 sf/gal), a double application (DA, 75 sf/gal), and a DA with 24 hours in between applications (DA-24). The testing also included a Geotextile, Geotext 601, and specimens with no bond-breaker. The materials were tested using push-off and slant shear test procedures. It was determined that from the tested materials the DA of curing compound proved to be the most effective, and the geotextile was the least effective. The same trend is shown in the results from both procedures and replicating the trends of performance set by previous research. The geotextile showed a sticking point when tested in shear, where the specimen failed but the material still showed residual shear capacity.

This thesis covers the development of nuclear propulsion in the Royal Navy from the first proposal in 1946 to the start-up of the last core improvement for the first submarine reactor power plant PWR 1 in December 1974. There are three topics: Political, what problems were encountered in transferring nuclear knowledge from the US in the post-war period and what support was there for the development of nuclear propulsion? Militarily, what was the requirement to develop nuclear propulsion and why submarines in particular? Technical, were the problems associated with nuclear energy fully appreciated, did the UK have the technical and engineering capability to develop nuclear propulsion? Primary research concentrated on the National Archives; research was also conducted on unreleased files relevant to the period held by Director Nuclear Propulsion. A number of retired naval officers involved in the early stages of nuclear propulsion development gave interviews, copies of their papers and were generally enthusiastic to assist with any queries. Visits were paid to the archives of CND at the London School of Economics and the Broadlands (Mountbatten) Archives at Southampton University. Secondary research was conducted at the Royal Institution of Naval Architects, the Institution of Mechanical Engineers, the British Library, Plymouth Central Library, Plymouth University Library and using accredited online resources. Information pertaining to, the Royal Navy's Naval Nuclear Propulsion Programme (NNPP) is covered by the Official Secrets Act and the Mutual Defence Agreement (MDA) 1958. Due to the nature of the subject matter very little has been written on the topic of the Royal Navy's development of nuclear propulsion. Having recently written a history of the submarine service since World War II, Peter Hennessy and James Jinks naturally included a chapter on the Royal Navy's adoption of nuclear propulsion in The Silent Deep: The Royal Navy Submarine Service since 1945, (2015). However, the chapter, 'A New Epoch': Towards the Nuclear Age, is focussed on UK attempts during the 1950s to secure US collaboration. There is no technical investigation of the Royal Navy's nuclear reactor programme during this era nor of the reactor core improvements that resulted from the purchase of the S5W reactor under the 1958 Mutual Defence Agreement. The Silent Deep contains no references to any United Kingdom Atomic Energy Authority files held at the National Archive and perpetuates the errors contained in Philip Ziegler's biography of Mountbatten which stem from Mountbatten's draft (MB1/K208A) which he forwarded to Captain (Rear Admiral) Peter Hammersley for comment; see Mountbatten Corrections in chapter four. Apart from the political considerations and military motives for developing nuclear propulsion in the Royal Navy, this thesis primarily focusses on the technical problems to be overcome by all participants in the Royal Navy's development of nuclear propulsion. Therefore, this thesis adds considerably to the historiography of nuclear propulsion and of Royal Navy submarines in particular.

Excess phosphorous in water ways is known to be a cause of harmful algal blooms. These blooms have caused problems with water aesthetics and recreational use. Water Treatment Residual (WTR) has been shown to have an affinity for phosphorous. Since WTR is a bi-product of the drinking water treatment process it has the potential of being a low-cost alternative to remove excess phosphorous from water ways, potentially preventing harmful algal blooms. A previous study proved there was a beneficial reuse for WTR produced at the Akron Water Treatment plant for binding excess phosphorous. This research thesis looked further into Akron Water Treatment Plants WTR, to see if baking could increase its phosphorous adsorption capacity.Initial 24-hour sorption studies determined optimal baking temperatures of 175°C for Al-WTR (ce = 0.31 mg/L, qe = 117.21) and 150°C for PAC-WTR (ce = 0.20 mg/L, qe = 120.00). Isotherm studies for baked Al-WTR (175°C) and PAC-WTR (150°C) found that there was a net desorption of phosphorous when in distilled background solution. A statistical analysis across all experimental conditions determined that baked PAC-WTR (mean qe 11.00 mg/kg) performed significantly (ρ < 0.05) better than baked Al-WTR (mean qe 8.18 mg/kg). When the specific condition of the isotherm experiments were considered, baked PAC-WTR sorbed more PO4 (mean qe 36.64 mg/kg) (ρ < 0.05) when subjected to raw water at 20°C and static in conditions. Baked Al-WTR was the next best (mean qe 21.42 mg/kg) significantly (ρ < 0.05) in 5°C Static in raw water.Continuous flow column tests were also conducted to find the sorption maximum of the baked WTR, and to compare the adsorption capacity of As-Is WTR versus baked WTR conducted. Baked WTR was found to have an affinity for phosphorous with a sorption capacity of 7.91 mg-P/g-WTR for baked Al-WTR and 16.21 mg-P/kg-WTR. When compared to As-Is WTR, baked PAC WTR was the only material found to have a higher adsorption capacity by 83% compared to As-Is PAC-WTR at the same run time.After analysis of all experiments it was concluded that As-Is WTR performed significantly (ρ < 0.05), better than baked WTR and would be the recommended reuse of Akron Water Treatment Plant’s WTR for the adsorption of phosphorous. There were not many papers on the reuse of baked WTR. This paper evaluated the economics and the effect of baking on phosphorous adsorption. While it was not found to be beneficial for phosphorous adsorption at selected temperatures, the analytical methods used could be employed for further analysis on the effects of baked WTR.

There is a large body of systems literature that studies and learns from adaptive team performance in high-complexity domains (nuclear, healthcare, aviation). However, there is little to no systems research on arguably the most popular team setting: organized sports. Using converging methods, this study looked at (1) patterns of adaptation that are revealed when using a resilience engineering lens to look at intra- and inter- game coaching decisions, and (2) the strategies that coaches use to affect individual and system performance on a collegiate basketball team. The specific concepts borrowed from resilience engineering used to view this domain were common ground, mutual directability, interpredictability, polycentric control and being poised to adapt, amongst others. A resilience engineering lens was used due to the fact that it is known to be critically important to other complex adaptive systems.Decision-making and adaptations in sports are commonly thought to be targeted towards each individual. Through structured interviews, this study found that there are hidden triggers and decision-making processes that are system-focused rather than individually-focused when coaches assess the need for an adaptation and execute it. In addition, the existence of different time scales to implement and execute adaptations was found to be a critical point that coaches exploit in order to increase the readiness to adapt during high tempo periods. Basketball has high varying tempos on multiple time scales, from longest to shortest: practices and film sessions between games, halftime breaks, timeout breaks, play breaks and in-play breaks. This study identifies various hidden system level strategies that coaches use in order to achieve successful team performance across the different time scales: increasing the levels of common ground, directability, predictability, readiness to adapt and polycentric control. For example, this research found that the development of coded terminology during low tempo periods can help a system implement adaptations in very short timeframes during high tempo periods, which is a key to successful performance. The paper will present a detailed explanation and various examples of how these strategies translate to a basketball game. This research calls into question much of the conventional wisdom assumptions about the importance of individual traits (e.g. agility, speed, strength) and shows how often decisions are made that reduce the overall team performance on these dimensions, but improve aspects of team or system performance (e.g. coordination, readiness to adapt, predictability, etc.). This paper will present the importance of considering these strategies and patterns in the future when trying to advance the development and design of complex adaptive systems that are resilient in face of decompensation.