Digital Commons Network^™

Combining Blockchain And Swarm Robotics To Deploy Surveillance Missions, Ardalan Razavi

Master's Theses

Current swarm robotics systems are not utilized as frequently in surveillance missions due to the limitations of the existing distributed systems' designs. The main limitation of swarm robotics is the absence of a framework for robots to be self-governing, secure, and scalable. As of today, a swarm of robots is not able to communicate and perform tasks in transparent and autonomous ways. Many believe blockchain is the imminent future of distributed autonomous systems. A blockchain is a system of computers that stores and distributes data among all participants. Every single participant is a validator and protector of the data in …

Mobility Through Droughts: Cross-Sectional Analysis Of Femora In A San Francisco Bay Area Prehistoric Native Population, Sarah M. Luce

Master's Theses

This thesis aims to infer mobility patterns in the California prehistoric burial population of CA-ALA-329 (Ryan Mound) by conducting cross-sectional analysis on femoral bones. CA-ALA-329 is considered to be a burial ground used by precontact Ohlone natives in the San Francisco Bay Area. Glacial changes, pollen studies, and

tree-ring data show shifts in climate change occurred during the Late Phase 1 Period, causing warmer and drier temperatures throughout California. Seventy-seven femora were analyzed in this study including 26 femora representing the Middle Period and 51 representing the Late Phase 1 Period. Cross-sectional geometric formulae were applied to measurements collected at …

The Effects Of Salinity On Zootechnical Performance Of Spotted Seatrout (Cynoscion Nebulosus) In Recirculating Aquaculture Systems, Eric Gigli

Master's Theses

The spotted seatrout (Cynoscion nebulosus) is a euryhaline finfish candidate for marine aquaculture in the northern Gulf of Mexico. Aquaculture of this species currently uses salinities of 25 psu or greater making production challenging in areas where high salinity water is not available. This study aimed to document the effects of salinity on zootechnical performance of spotted seatrout embryos, early larvae, and juveniles in recirculating aquaculture systems to assist with the development of protocols for low salinity culture.

Embryos obtained from a volitional spawn at 29 psu were incubated at three salinities (12.5, 18.75, or 25 psu) until …

A Systematic Theoretical Study Of Topological Insulator Bi₂Se₃, Thomas Reid

Master's Theses

No abstract provided.

Understanding Trade-Offs Between Built And Natural Assets In Coastal Management Projects For Inland, Coastal Residents Using Latent Class Modeling Techniques: An Application To The Connecticut Coastline, Julia Dumaine

Master's Theses

Climate change threatens our established communities worldwide through consistently increased average surface temperatures, rising sea levels, and precipitation extremes, and Connecticut is no exception (U.S. Global Change Research Program 2017). As coastal communities in Connecticut increase their focus on mitigating the effects of climate change, they are not always able to incorporate town residents’ preferences and values into their planning; particularly those residents who may not receive a direct benefit from the plan of which they contribute tax dollars towards. Our study attempts to estimate these preferences and values by using a choice experiment survey distributed across the Connecticut coastline …

Non-Destructive Evaluation Of Thermal Barrier Coatings Using Direct Heat Flux Method, Amadeusz Adam Nasuta

Master's Theses

Thermal barrier coatings are essential for reliable and efficient turbine engines. The coatings allow the engine to operate at higher temperatures and protect the super alloy components within the hot section. Turbine hot section components have complex geometries. Complex geometries can lead to inconsistent coatings. It is critical to determine which components have defective coatings because engine manufacturers warranty these parts and under life parts have large costs associated with them. Non-destructive detection of damage progression is useful for accurate part lifetime prediction and also in root cause analysis. The present thesis describes a new, non-destructive approach to test thermal …

Model-Based Medium-Voltage Induction Machine Insulation Material Characterization, Arshiah Yusuf Mirza

Master's Theses

The voltage and frequency handling capability of power converter modules have tremendously increased with the penetration of wide-band-gap (WBG) semiconductor technology in power electronics. However, very little is known about the effect of the high-voltage high-frequency transients exerted by WBG power electronics on insulation materials. This thesis investigates the effect of high-voltage, high-frequency transients on aging and breakdown characteristics of insulation materials. The aim of this research was to analyze this breakdown and develop the behavioral model of the breakdown time when such insulation materials are used in inverter-fed medium-voltage induction machines. As a part of this research, a series …

Improving The Accuracy Of A Finite Element Based Manufacturing Simulation: A Case Study Of Laser-Induced Bending In A Thin Metal Sheet, Joseph Johanson

Master's Theses

Finite element analysis (FEA) has become an increasingly popular tool used by researchers and professionals for comparing experimental data to theoretically expected values. Its use can prove to be an invaluable resource when analyzing or designing a system by giving the user the ability to understand the process being modeled at a much deeper level. However, finite element analysis it is still prone to generating inaccurate results if not used properly. When simulating certain physical processes, such as those found during manufacturing, the obtained results are sometimes prone to error when compared with their experimentally obtained counterparts.

The present work …

The Influence Of Sentence Context On Phonetic Recalibration, Sahil Luthra

Master's Theses

Individual talkers vary considerably in how they produce different speech sounds, and a challenge for the listener is to learn the appropriate mapping between acoustics and phonetic categories for an individual talker. Several studies have shown that listeners are able to leverage various sources of context (e.g., coincident visual information, lexical knowledge) to guide this process, sometimes termed perceptual learning of speech. Here, we examine how sentence-level semantic information – specifically, whether preceding sentence context is predictive of an upcoming word – might modulate the size of learning effects. Across a series of perceptual learning experiments, we manipulate how learning …

Thermophysical Properties And Characterization Of Diamond Silicon Carbide, Alexandra Merkouriou

Master's Theses

No abstract provided.

Topology Optimization Of Space Frames Via Geometry Projection, Manal Tahhan

Master's Theses

There is growing interest in space agencies to design lunar habitats for different stages of habitation. In this work, we present a topology optimization method to design a class of these structures consisting of rigid space frames with elements transported from earth and assembled in situ. Since the space frame must be made of stock material for ease of transportation and assembly, this work employs the geometry projection method, which is a topology optimization technique that render designs made exclusively of geometric primitives. This work makes three contributions to the geometry projection method that are necessary for the design of …

Effect Of Bio-Augmentation Product Biowish® Septic Rescue On The Wastewater Treatment Performance Of Residential Septic Tanks, Kimberly Michelle Lamar Merilles

Master's Theses

Residential septic systems provide reliable wastewater treatment for over 26 million homes and facilities in the United States, and many more worldwide. When properly maintained, these systems are reliable, low-cost, and long-term treatments for residential wastewater. When neglected, septic systems can fail and lead to health concerns and ecological harm to soil and groundwater contamination through the improperly treated wastewater effluent.

This study tested the effect of the bio-augmentation product BiOWiSH® Septic Rescue of BiOWiSH® Technologies International, Inc. (hereafter referred to as BiOWiSH) on the biological treatment of residential septic tanks. BiOWiSH is meant to act as a bio-augmentation product …

Indoor Air Monitoring Of Ethanol And Benzene In A Pilot Winery Using Active Sampling, Andrew I. Kaneda

Master's Theses

Acute indoor concentrations of benzene and ethanol were evaluated in the California Polytechnic State University San Luis Obispo’s pilot winery workroom. Air samples were collected during four different wine-making activities: fermentation, fermentation with Brix content testing, post-alcoholic fermentation pressing, and storage/finishing. Average workroom benzene concentrations ranged from 0.05 to 0.12 mg/m³. Ethanol concentrations in the winery workroom varied with the activity, ranging from 0.9 to 12 mg/m³. Pressing and fermentation with Brix content testing both led to higher indoor ethanol concentrations than fermentation without Brix content testing and storage/finishing.

Tracer gas decay air exchange tests were …

Relevance Analysis For Document Retrieval, Eric Labouve

Master's Theses

Document retrieval systems recover documents from a dataset and order them according to their perceived relevance to a user’s search query. This is a difficult task for machines to accomplish because there exists a semantic gap between the meaning of the terms in a user’s literal query and a user’s true intentions. Even with this ambiguity that arises with a lack of context, users still expect that the set of documents returned by a search engine is both highly relevant to their query and properly ordered. The focus of this thesis is on document retrieval systems that explore methods of …

Investigation Of Design, Manufacture, Analysis, And Test Of A Composite Connecting Rod Under Compression, Thomas Juhl Rohrbach

Master's Theses

Composite materials hold great potential for the replacement of traditional materials in machines utilized on a daily basis. One such example is within an engine block assembly where massive components inherently reduce the efficiency of the system they constitute. By replacing metal elements such as connecting rods, cylinder caps, or a crank shaft with composite alternatives, a significant increase in performance may be achieved with respect to mechanical strength, thermal stability, and durability, while also reducing mass. Exploration of this technology applied to a connecting rod geometry was investigated through a combination of process development, manufacturing, numerical analysis and testing. …

Experimental Study And Modeling Of The Gm-I Dependence Of Long-Channel Mosfets, Michael Fong Cheng

Master's Theses

This thesis describes an experimental study and modeling of the current-transconductance dependence of the ALD1106, ALD1107, and CD4007 arrays. The study tests the hypothesis that the I-gm dependence of these 7.8 µm to 10 µm MOSFETs conforms to the Advanced Compact Model (ACM). Results from performed measurements, however, do not support this expectation. Despite the relatively large length, both ALD1106 and ALD1107 show sufficiently pronounced ‘short-channel’ effects to render the ACM inadequate. As a byproduct of this effort, we confirmed the modified ACM equation. With an m factor of approximately 0.6, it captures the I-gm dependence with sub-28% maximum error …

Experimental Optical Pulse Picker For Lawrence Livermore National Lab, Alexander Thomas Wargo

Master's Theses

Proprietary.

Perturbation Based Decomposition Of Semg Signals, Rachel Huettinger

Master's Theses

Surface electromyography records the motor unit action potential signals in the vicinity of the electrode to reveal information on muscle activation. Decomposition of sEMG signals for characterization of constituent motor unit action potentials in terms of amplitude and firing times is useful for clinical research as well as diagnosis of neurological disorders. Successful decomposition of sEMG signals would allow for pertinent motor unit action potential information to be acquired without discomfort to the subject or the need for a well-trained operator (compared with intramuscular EMG). To determine amplitudes and firing times for motor unit action potentials in an sEMG recording, …

Development Of A Myoelectric Detection Circuit Platform For Computer Interface Applications, Nickolas Andrew Butler

Master's Theses

Personal computers and portable electronics continue to rapidly advance and integrate into our lives as tools that facilitate efficient communication and interaction with the outside world. Now with a multitude of different devices available, personal computers are accessible to a wider audience than ever before. To continue to expand and reach new users, novel user interface technologies have been developed, such as touch input and gyroscopic motion, in which enhanced control fidelity can be achieved. For users with limited-to-no use of their hands, or for those who seek additional means to intuitively use and command a computer, novel sensory systems …

Exploring The Impact Of National Culture On Logistics Performance, Deepak Parathur Kesavan

Master's Theses

The increased logistics complexity due to supply chain globalization requires a deeper understanding of a country’s logistics performance. This performance is usually captured through infrastructure, services and procedure elements and understood in operational and economical terms. This thesis adds a social view to understand logistics performance variation across countries through focusing on their national culture dimensions. Using secondary data from the international Logistics Performance Index (LPI) report as well as the scores from Hofstede’s national culture dimension surveys, the impact of national culture on logistics performance was explored. Statistical results showed Power Distance and Uncertainty Avoidance dimensions were found to …

Sweep And Taper Analysis Of Surfboard Fins Using Computational Fluid Dynamics, Brandon James Baldovin

Master's Theses

The research presented here provides a basis for understanding the hydrodynamics of surfboard fin geometries. While there have been select studies on fins there has been little correlation to the shape of the fin and its corresponding hydrodynamic performance. This research analyzes how changing the planform shape of a surfboard fin effects its performance and flow field. This was done by isolating the taper and sweep distribution of a baseline geometry and varying each parameter individually whilst maintaining a constant span and surface area. The baseline surfboard fin was used as a template in Matlab to generate a set of …

A Study Of Face Embedding In Face Recognition, Khanh Duc Le

Master's Theses

Face Recognition has been a long-standing topic in computer vision and pattern recognition field because of its wide and important applications in our daily lives such as surveillance system, access control, and so on. The current modern face recognition model, which keeps only a couple of images per person in the database, can now recognize a face with high accuracy. Moreover, the model does not need to be retrained every time a new person is added to the database.

By using the face dataset from Digital Democracy, the thesis will explore the capability of this model by comparing it with …

Wastewater Treatment And Nitrogen Removal In Bench-Scale Photobioreactors Operated With Solids Recycling, Erik Hoffnagle

Master's Theses

This thesis examines the effect of solids recycling on nitrification, organic carbon removal, and algal-bacterial productivity in bench-scale photobioreactors (PBRs) simulating winter pond conditions in San Luis Obispo, California and a 6-acre raceway system in Delhi, California. Two sets of duplicate photobioreactors operated with or without solids recycling were fed primary clarifier effluent (1^oEff) for the first experiment, and facultative pond effluent (FAC) for the second experiment.

In both experiments mean productivity was lower in solids recycled PBRs (3.67 and 2.3 g/m²-day), than in controls without solids recycling (4.15 and 3.9 g/m²-day). When fed …

Design Of A Low-Cost Data Acquisition System For Rotordynamic Data Collection, Gregory S. Pellegrino

Master's Theses

A data acquisition system (DAQ) was designed based on the use of a STM32 microcontroller. Its purpose is to provide a transparent and low-cost alternative to commercially available DAQs, providing educators a means to teach students about the process through which data are collected as well as the uses of collected data. The DAQ was designed to collect data from rotating machinery spinning at a speed up to 10,000 RPM and send this data to a computer through a USB 2.0 full-speed connection. Multitasking code was written for the DAQ to allow for data to be simultaneously collected and transferred …

Strawberry Detection Under Various Harvestation Stages, Yavisht Fitter

Master's Theses

This paper analyzes three techniques attempting to detect strawberries at various stages in its growth cycle. Histogram of Oriented Gradients (HOG), Local Binary Patterns (LBP) and Convolutional Neural Networks (CNN) were implemented on a limited custom-built dataset. The methodologies were compared in terms of accuracy and computational efficiency. Computational efficiency is defined in terms of image resolution as testing on a smaller dimensional image is much quicker than larger dimensions. The CNN based implementation obtained the best results with an 88% accuracy at the highest level of efficiency as well (600x800). LBP generated moderate results with a 74% detection accuracy …

Supported Programming For Beginning Developers, Andrew Gilbert

Master's Theses

Testing code is important, but writing test cases can be time consuming, particularly for beginning programmers who are already struggling to write an implementation. We present TestBuilder, a system for test case generation which uses an SMT solver to generate inputs to reach specified lines in a function, and asks the user what the expected outputs would be for those inputs. The resulting test cases check the correctness of the output, rather than merely ensuring the code does not crash. Further, by querying the user for expectations, TestBuilder encourages the programmer to think about what their code ought to do, …

Real-Time Ray Traced Global Illumination Using Fast Sphere Intersection Approximation For Dynamic Objects, Reed Phillip Garmsen

Master's Theses

Realistic lighting models are an important component of modern computer generated, interactive 3D applications. One of the more difficult to emulate aspects of real-world lighting is the concept of indirect lighting, often referred to as global illumination in computer graphics. Balancing speed and accuracy requires carefully considered trade-offs to achieve plausible results and acceptable framerates.

We present a novel technique of supporting global illumination within the constraints of the new DirectX Raytracing (DXR) API used with DirectX 12. By pre-computing spherical textures to approximate the diffuse color of dynamic objects, we build a smaller set of approximate geometry used for …

Dish: Democracy In State Houses, Nicholas A. Russo

Master's Theses

In our current political climate, state level legislators have become increasingly impor- tant. Due to cuts in funding and growing focus at the national level, public oversight for these legislators has drastically decreased. This makes it difficult for citizens and activists to understand the relationships and commonalities between legislators. This thesis provides three contributions to address this issue. First, we created a data set containing over 1200 features focused on a legislator’s activity on bills. Second, we created embeddings that represented a legislator’s level of activity and engagement for a given bill using a custom model called Democracy2Vec. Third, we …

A Higher-Order Method Implemented In An Unstructured Panel Code To Model Linearized Supersonic Flows, Jake Daniel Davis

Master's Theses

Since their conception in the 1960s, panel codes have remained a critical tool in the design and development of air vehicles. With continued advancement in computational technologies, today's codes are able to solve flow fields around arbitrary bodies more quickly and with higher fidelity than those that preceded them. Panel codes prove most useful during the conceptual design phase of an air vehicle, allowing engineers to iterate designs, and generate full solutions of the flow field around a vehicle in a matter of seconds to minutes instead of hours to days using traditional CFD methods. There have been relatively few …

Microplasmas In Zno Nano-Forests Under High Voltage Stress, Nafisa Noor

Master's Theses

No abstract provided.