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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.]

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.]

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.

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.]

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.

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 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.

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.]

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.

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.]

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.