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Item Hot Electron Effect in Ultrathin Photovoltaic Junctions(North Dakota State University, 2012) Mihaylov, Deyan IvovThe focus of the research work described in the following thesis is increasing the efficiency of photovoltaic devices by reducing hot carrier thermalization losses. In principle this can be achieved by reducing the size of the absorber down to lengths comparable to the thermalization length for hot carriers. With the use of ultrathin absorbers hot carrier can be collected before they have reached thermal equilibrium with the lattice. The theoretical work on the subject is comprised of improving the empirical relationship developed in the most recent publication on the topic by. By making the assumption that the energy loss rate fits the exponential decay model, an expression for the energy as a function of absorber thickness was developed. The experimental work consist of fabricating devices with different absorber thicknesses and testing their ability to show change in performance due to collection of hot electrons.Item NDSU's Back on TRAC Program: Policy Recommendations(North Dakota State University, 2010) Gonzales, Carmen CaitlinAlcohol and other drug use by college students has been considered by college administrators to be problematic for many years, but strategies in place were not effective or were being under-utilized. Data taken from both the NDSU CORE Survey on Alcohol and Other Drug Use as well as the national CORE survey indicate that many students use alcohol as their drug of choice; 71 % of those surveyed reported using alcohol within the 30 days prior to survey administration. In 2006, North Dakota State University was selected as a pilot institution for the Back on TRAC program. Back on TRAC utilizes a holistic approach based on the drug court model and public health and combines this approach with rewards and sanctions for compliance with program requirements to provide treatment for substance abuse to college students. The program was implemented in 2008, and since then, 8 students have participated in Back on TRAC at NDSU. Based on the Back on TRAC program used at NDSU, three recommendations have been made to increase the provision of services to program participants. These recommendations were developed using information collected about the program currently in place at NDSU, as well as information collected about the Back on TRAC program at Colorado State University, Oklahoma State University, and Texas A&M.Item New Old Stock(North Dakota State University, 2012) Lippert, NicholasThis project, Detroit’s New Workforce: A Detroit Renewable Energy Workforce Training Center, examines how and where the sense of place exists within a construction. From that conclusion, it will investigate how sense of place lives within a new environment. The proposed 29,000 square foot commercial building in downtown Detroit sits on the site of a recently demolished building. The new construction will continue the previous sense of place to make the it more significant culturally.Item The Boundaries of Social Entrepreneurship in Higher Education: A New Framework(North Dakota State University, 2016) Reid, Michele McFaddenSocial entrepreneurship (SE) incorporates the more ethical dimensions of innovative business practices in the pursuit of financial sustainability in the advancement of societal goals, and is intended to empower all participants while bringing about positive changes in communities and society at large. An increasing number of colleges and universities are now embracing SE to stay competitive in the higher education market, find new sources of income in times of fiscal constraint, and align with their public service missions. However, despite the interest in SE on the part of the academic community, there is no broad or consistent understanding regarding what actually constitutes SE in higher education settings (SEHE), or about how it is being carried out in the institutions that have adopted SEHE. A multi-case study design explores a proposed initial SEHE framework developed from the literature through a qualitative analysis of the experiences of five higher education institutions recognized for their adoption of SE practices. This qualitative approach utilizing the lens of structuration theory enables the development of a complex understanding of SEHE as a multifaceted social phenomenon derived through the examination of its actors in their structural context. The revised SIEHE framework, informed by the experiences of these exemplar institutions, is intended both to advance scholarly understanding of the elements and process of SIEHE, and to serve as a model for those undertaking or considering SE implementations at other colleges and universities. The framework sheds new light on the definitional and operational aspects of SE, and translates concepts that have previously been largely confined to the business literature to other disciplines, enabling their adoption by scholars and practitioners in such diverse areas as education, the social sciences, and the liberal arts. While allowing for a broader scope of the types of socially beneficial projects that could be undertaken by agents, including faculty from a larger range of disciplines, SIEHE’s emphasis on financial sustainability should also be attractive to administrations for enabling access to alternative funding sources.Item Parallel Particle Swarm Optimization(North Dakota State University, 2016) Manne, PriyankaPSO is a population based evolutionary algorithm and is motivated from the simulation of social behavior, which differs from the natural selection scheme of genetic algorithms. It is an optimization technique based on swarm intelligence, which simulates the bio-inspired behavior. PSO is a popular global search method and the algorithm is being widely used in conjunction with several other algorithms in different fields of study. Modern day computational problems demand highly capable processing machines and improved optimization techniques. Since it is being widely used, it is important to search for ways to speed up the process of PSO, as the complexity of the problems increase. The paper describes a way to improve it via parallelization. The parallel PSO algorithm’s robustness and efficiency is demonstrated. This paper evaluates the parallelized version of the PSO algorithm with the use of Parallel Computing Toolbox available in Matlab.Item Surface Property Modification of Coatings via Self-Stratification(North Dakota State University, 2010) Pieper, Robert JosephBiological fouling occurs everywhere in the marine environment and is a significant problem for marine vessels. Anti-fouling coatings have been used effectively to prevent fouling; however, these coatings harm non-targeted sea-life. Fouling-release coatings (FRC) appear to be an alternative way to combat fouling. FRC do not necessarily prevent the settlement of marine organisms but rather allow their easy removal with application of shear to the coatings surface. These coatings must be non-toxic, non-leaching, have low surface energy, low modulus, and durability to provide easy removal of marine organisms. Here the goal is to develop FRC based on thermosetting siloxane-polyurethane, amphiphilic polyurethane, and zwitterionic/amphiphilic polyurethane systems. A combinatorial high-throughput approach has been taken in order to explore the variables that may affect the performance of the final coatings. Libraries of acrylic polyols were synthesized using combinatorial high-throughput techniques by either batch or semi-batch processes. The design of the experiments for the batch and semi-batch processes were done combinatorially to explore a range of compositions and various reaction process variables that cannot be accomplished or are not suitable for single reaction experiments. Characterization of Rapid-GPC, high-throughput DSC, and gravimetrically calculated percent solids verified the effects of different reaction conditions on the MW, glass transition temperatures, and percent conversion of the different compositions of acrylic polyols. Coatings were characterized for their surface energy, pseudobarnacle pull-off adhesion, and were subjected to bioassays including marine bacteria, algae, and barnacles. From the performance properties results the acrylic polyol containing 20% hydroxyethyl acrylate and 80% butyl acrylate was selected for further siloxane-polyurethane formulations and were subjected to the same physical, mechanical, and performance testing. Amiphiphilic copolymers based on PDMS molecular weight and the addition of PEG based polymer blocks on the properties of acrylic-polyurethane coatings were explored. The key properties screened were surface energy, determined by contact angle measurements using water and methylene iodide, dynamic water contact angle, and pseudobarnacle adhesion properties. The data from all of the biological assays indicates that the novel coatings were able to resist fouling and have low fouling adhesion for the broad variety of fouling organisms tested.Item The Role of the Gut Microbiota in Sustained Weight Loss Following Roux-en-Y Gastric Bypass Surgery(North Dakota State University, 2018) Fouladi, FarnazRoux-en-Y Gastric Bypass (RYGB) surgery is one of the most effective approaches for the treatment of severe obesity. Despite substantial weight loss following RYGB, a considerable proportion of patients experience weight regain or insufficient weight loss. The proposed research aimed to investigate the role of the gut microbiota in weight regain or suboptimal weight loss following RYGB. The gut microbiota composition in post-RYGB patients who experienced successful weight loss (SWL, n=6), post-RYGB patients who experienced poor weight loss (PWL, n=6), and non-surgical controls (NSC, n=6) who were age- and BMI-matched to the SWL group (NSC, n=6) were characterized through 16S rRNA gene sequencing. To further investigate the impact of the gut microbiota on weight profile, human fecal samples were transplanted into antibiotic-treated mice through oral gavage. Food intake and body weight were measured at weekly intervals for a month. At five weeks following colonization mice were randomly switched to a Western Diet or maintained on a normal diet. The results showed that Lactobacillales, Enterobacteriales, and Verrucomicrobials were enriched in both surgical groups compared to the NSC group. No significant difference was observed in the gut microbiota composition between PWL and SWL patients. However, transfer of the gut microbiota from human patients into antibiotic-treated mice resulted in significantly greater weight gain in PWL recipient mice compared to SWL recipient mice at four weeks following colonization (15.03±2.59% versus 7.88±1.28%, F(2,41)=4.01 p=0.026). We found that Barnesiella, Gordonibacter, Parasutterella, Clostridium cluster XVIa were effectively transferred from humans to mice and were associated with weight gain in recipient mice. Interestingly, Barnesiella that tended to be higher in PWL humans was also significantly higher in PWL recipient mice compared to SWL and NSC recipient mice. All three groups of recipient mice gained weight when they were placed on the Western Diet regardless of human donor group. In summary, the results indicate that the gut microbiota are at least functionally different between PWL and SWL patients. Some taxa may contribute to weight gain after surgery. Future studies will need to determine the molecular mechanisms behind the effects of the gut bacteria on weight regain after RYGB.Item Protein Functional Site Prediction Using the Shortest-Path Graph Kernel Method(North Dakota State University, 2013) Benaragama Vidanelage, Malinda Vikum SanjakaOver the past decade Structural Genomics projects have accumulated structural data for over 75,000 proteins, but the function of most of them are unknown due to limitation of laboratory approaches for discovering the functionality of proteins. Computational methods play key roles to minimize this gap. Graphs are often used to describe and analyze the geometry and physicochemical composition of bimolecular structures such as, chemical compounds and protein functional sites. In this study, we developed an innovative graph method to represent protein surface based on how amino acid residues contact with each other. Further, we implemented a shortest-path graph kernel method to calculate similarities between the graphs. The nearest-neighbor method was used to compare the similarity of kernel values and predict functional sites of protein structures. The proposed approach achieved accuracy as high as 77.1% and would provide a useful tool for functional site prediction.Item The Genesis Project : exploring the convergence of architecture, music, & life(North Dakota State University, 2015) Halvorson, TimothyMusic is an innate human quality that provokes physical, mental, and spiritual responses both consciously and subconsciously, and consequently, has the capacity to change the environment. Architecture can be designed as a vehicle for creating acoustically rich environments and musical opportunities that are desirable for guests and promote social exchange and healing. Architecture can be specifically designed to acoustically tune and direct sound in particular fashions that promote social, physiological, and cultural well being. The Performing Arts & Healing Center challenges conventional perceptions of what “instrument” and “music” are by creating spaces that can be healing and invigorating through the embodied composition of select materials,shapes, and landscaping. The symphony of nature. Further, a variety of interactive musical mediums encourage guests to tangibly engage with music rather than simply stand as observers. The result is a constant stream of activity transforming the Center into an instrument for positive cultural change. Title: The Genesis Project: Exploring the Convergence of Architecture, Music, & Life Typology: Performing Arts & Healing Center Site: Rochester, MN USA. Project Size: 350,000 Square Feet.Item Relationship between Visual Obstruction Reading and Herbage Production for Ecological Sites in a Semi-Arid Climate of the Northern Plains(North Dakota State University, 2010) Woehl, Derek DevonneCarbon nanotubes have been the main focus in science and engineering fields lately for their extraordinary properties. But carbon nanotube fabrication process is very expensive, particularly for reinforcements and structural composite applications. Instead of working towards developing lower cost nanotubes, an alternate solution to resolve the problem is to formulate a cost effective reinforcement referred to as graphene nanoplatelets. These nanoplatelets have excellent mechanical as well as electronic properties opening up for several applications in various fields. Their structure with carboncarbon bonds make them stronger and stiffer. Single nanotubes can be used as reinforcements in one direction, while the graphite nanoplatelets are effective in two directions yielding a higher degree of stiffness and strength in a matrix. In this thesis, a molecular dynamic computer simulation technique was used to explore the atomic scale and dynamics of graphene nanoplatelets and carbon nanotubes embedded in polyethylene matrix. The mechanical properties of the carbon nanotubes and nanoplatelets polymer composite models were studied individually along with a comparison between composite models. The overall system was modeled using material studio software with the implementation of periodic boundary conditions to determine the properties. The stress strain curves revealed that the length and the volume fraction of the nanotube/nanoplatelets had a significant effect on the mechanical properties of the composite. The stiffness of the composite with long reinforcement length increased relative to the polymer in the longitudinal direction and shows an anisotropic behavior. Significant enhancement was observed in the Young's modulus with the increase in the volume fraction of the nanotubes/nanoplatelets because of the well known effect of the increase in the load transfer between the polymer and the reinforcements. Also increasing the volume fraction of the short nanotubes/nanoplatclets provided very little improvement in stiffness compared to the longer length nanotubes/nanoplatelets. Results also showed that the graphene nanoplatelet reinforced composite properties were very comparable to the nanotubes reinforced composites even under weak vander Waal interactions.