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Extrinsic And Intrinsic Control Of Integrative Processes In Neural Systems, Anirban Nandi

McKelvey School of Engineering Graduate Student Theses & Dissertations

At the simplest dynamical level, neurons can be understood as integrators. That is, neurons accumulate excitation from afferent neurons until, eventually, a threshold is reached and they produce a spike. Here, we consider the control of integrative processes in neural circuits in two contexts. First, we consider the problem of extrinsic neurocontrol, or modulating the spiking activity of neural circuits using stimulation, as is desired in a wide range of neural engineering applications. From a control-theoretic standpoint, such a problem presents several interesting nuances, including discontinuity in the dynamics due to the spiking process, and the technological limitations associated with …

Reconstruction Algorithms For Novel Joint Imaging Techniques In Pet, Homayoon Ranjbar

McKelvey School of Engineering Graduate Student Theses & Dissertations

Positron emission tomography (PET) is an important functional in vivo imaging modality with many clinical applications. Its enormously wide range of applications has made both research and industry combine it with other imaging modalities such as X-ray computed tomography (CT) or magnetic resonance imaging (MRI). The general purpose of this work is to study two cases in PET where the goal is to perform image reconstruction jointly on two data types.

The first case is the Beta-Gamma image reconstruction. Positron emitting isotopes, such as ¹¹C, ¹³N, and ¹⁸F, can be used to label molecules, and tracers, such …

Abiotic- And Biotic-Formation Of Manganese Oxides And Their Fate In Environmental Systems, Haesung Jung

McKelvey School of Engineering Graduate Student Theses & Dissertations

Manganese (hydr)oxide (Mn (hydr)oxide) minerals are ubiquitous in aquatic and terrestrial environments. These minerals have high surface areas and are highly sorptive and redox active. From decades of accumulated knowledge about natural redox cycling, we have found that Mn (hydr)oxides play critical roles as electron donors and acceptors in elemental geochemical cycling and biological metabolisms in nature. Thus, Mn (hydr)oxides have garnered increasing interest to understand natural systems. Considering the variety of redox reactions with Mn (hydr)oxides in nature, it is also expected that there should be diverse pathways to form Mn (hydr)oxides through abiotic and biotic processes. Previous studies …

Mechanics Of The Developing Brain: From Smooth-Walled Tube To The Folded Cortex, Kara Ellspermann Garcia

McKelvey School of Engineering Graduate Student Theses & Dissertations

Over the course of human development, the brain undergoes dramatic physical changes to achieve its final, convoluted shape. However, the forces underlying every cinch, bulge, and fold remain poorly understood. This doctoral research focuses on the mechanical processes responsible for early (embryonic) and late (preterm) brain development.

First, we examine early brain development in the chicken embryo, which is similar to human at these stages. Research has primarily focused on molecular signals to describe morphogenesis, but mechanical analysis can also provide important insights. Using a combination of experiments and finite element modeling, we find that actomyosin contraction is responsible for …

The Inter-Laminar Shearing Effect On Wrinkle Development In Composite Forming Processes, David Sundquist

McKelvey School of Engineering Graduate Student Theses & Dissertations

Composite materials are becoming prevalent in aerospace industries as the uniqueness of the composite structure allows the composite to be tailored specifically for individual applications. Many fabrication techniques produce defects in composite parts such as wrinkles, fiber waviness, fiber misalignment, and porosity. The driving mechanisms behind these defects occurring during forming processes are not fully understood and, thus, characterization formation of these defects in a uncured state is beneficial to optimize composite processing. This work primarily investigated the influence of how uncured pre-impregnated carbon ply properties affect the wrinkling behavior of a composite laminates. Several factors affecting composite ply forming …

Characterizing Anisotropy In Fibrous Soft Materials By Mr Elastography Of Slow And Fast Shear Waves, John Larson Schmidt

McKelvey School of Engineering Graduate Student Theses & Dissertations

The general objective of this work was to develop experimental methods based on magnetic resonance elastography (MRE) to characterize fibrous soft materials. Mathematical models of tissue biomechanics capable of predicting injury, such as traumatic brain injury (TBI), are of great interest and potential. However, the accuracy of predictions from such models depends on accuracy of the underlying material parameters. This dissertation describes work toward three aims. First, experimental methods were designed to characterize fibrous materials based on a transversely isotropic material model. Second, these methods are applied to characterize the anisotropic properties of white matter brain tissue ex vivo. Third, …

Two-Component Hydrogel As Biomimetic Vitreous Substitutes, Sruthi Santhanam

McKelvey School of Engineering Graduate Student Theses & Dissertations

The vitreous humor of the eye is a biological hydrogel principally composed of fibrillary collagen interspersed with semi-flexible polyelectrolyte, hyaluronic acid (HA). Certain pathological conditions necessitate its removal and replacement. Current vitreous substitutes, such as silicone oils and perfluorocarbons, are hydrophobic, do not resemble the properties of the vitreous, and have known complications. An ideal vitreous substitute should have properties of the natural vitreous, perform its functions, and be biocompatible in the eye. Inspired by the structure and composition of the natural vitreous, we used bio-mimicry to develop an injectable two-component hydrogel. The hydrogel is composed of a fibrillary gellan, …

Interdisciplinary Team Approach In Fall Prevention: Physician Perspective Focus, Anna Gryn

Master's Projects and Capstones

An in-hospital fall is a devastating event for patients and care providers resulting in injuries, physiological and psychological patient declines, and sometimes deaths. Furthermore, fall related costs greatly increase hospitals’ expenses and cause massive distress to caregivers and health providers. Many patient-specific, organizational, and seemingly erratic factors contribute to the occurrence of in-hospital falls. Despite this, hospitals must undertake consistent evidence-based measures to prevent fall occurrences as much as possible.

The traditional nursing approach to falls prevention is not sufficient to control fall rates because the issue is too complex and must be approached from multiple perspectives rather than just …

Gendered Impacts Of Community-Based Conservation Initiatives In Kimana/Tikondo Group Ranch Outside Of Amboseli National Park, Megan Clemens

Master's Theses

Community-based conservation has become a common solution to addressing local communities needs and concerns when it comes to conservation initiatives associated with, or outside the boundaries of national parks. Community-based initiatives associated with Amboseli National Park in southern Kenya mark one of the first attempts to include local communities in conservation initiatives and management as well as establish systems of benefit sharing between conservation and local communities. However, a critique of community-based conservation initiatives points out they often assume community homogeneity. Assumption of community homogeneity leads to inequities in benefits sharing, exclusion of subgroups (women, ethnic minorities) or even exacerbate …

Higher Education As A Development Tool: An Impact Assessment In Dzaleka Malawi, Emily Golike

Master's Theses

The purpose of this study is to determine the efficacy of accredited online diploma programs within refugee camps. When individuals are confined to camps and unable to work and travel in search of economic opportunity, does completing an accredited diploma program improve their quality of life and contribute to their human capital? Can higher education in refugee camps produce sustainable social service projects that benefit residents? There is a demonstrated value in a liberal arts education, but which aspects of this learning schema are most beneficial in the refugee camp context have yet to be explored.

The study conducted in …

Migrant Ridesharing Drivers In San Francisco: A Case Of Blocked Mobility?, Shireen Tofig

Master's Theses

Migrants have long turned to self-employment in host country labor markets due to not only racial and ethnic prejudices, but also issues of local language proficiency and lack of recognition of the academic degree from the sending country. The taxi industry, one particular occupational niche dominated by migrants, has long been studied by scholars. However, the industry has evolved into a newer and understudied form of transportation: ridesharing. This study argues that in the case of the ridesharing industry, drivers did indeed turn to the occupation because of factors such as insufficient English language level and foreign academic degrees, but …

Planning Cities, Economically Or Communally: A Comparative Study Of Amsterdam And San Francisco, Raina Dawn Whittekiend

Master's Theses

Globalization has spun “community” off its axis. What once defined community is no longer the current state of the community. Increased economic transactions have led to the instability of communities that once depended on one another at the local level. These communities are now dependent on systems that do not know nor understand their actors. This lack of relationship between development and subject is witnessed and highly scrutinized in developing countries all over the world and has been intensely researched in academic literature. This thesis intends to better understand why in modernized global cities these same processes of development and …

Life Being An International Student In The United States: Acculturation, Culture Shock, And Identity Transformation, Lai Yan Vivyan Lam

Master's Theses

The population of international students at community colleges in the United States has increased significantly over the past decade. International students play a big role in building the cultural diversity on campus by bringing over different cultures and sharing their global perspective to the local community. However, they often face challenges adapting into American culture due to cultural differences in education system, language, lifestyle, etc. By looking into the acculturation process of international students to analyze the culture shock and cultural identity changes they experienced, this paper intends to seek ways to help this group of students to ease their …

First Narrow-Band Search For Continuous Gravitational Waves From Known Pulsars In Advanced Detector Data, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov

Physics & Astronomy Faculty Publications

Spinning neutron stars asymmetric with respect to their rotation axis are potential sources of continuous gravitational waves for ground-based interferometric detectors. In the case of known pulsars a fully coherent search, based on matched filtering, which uses the position and rotational parameters obtained from electromagnetic observations, can be carried out. Matched filtering maximizes the signal-to-noise (SNR) ratio, but a large sensitivity loss is expected in case of even a very small mismatch between the assumed and the true signal parameters. For this reason, narrow-band analysis methods have been developed, allowing a fully coherent search for gravitational waves from known pulsars …

First Low-Frequency Einstein@Home All-Sky Search For Continuous Gravitational Waves In Advanced Ligo Data, B. P. Abbott, R. Abbott, T. D. Abbott, F. Acernese, K. Ackley, C. Adams, Teviet Creighton, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov

Physics & Astronomy Faculty Publications

We report results of a deep all-sky search for periodic gravitational waves from isolated neutron stars in data from the first Advanced LIGO observing run. This search investigates the low frequency range of Advanced LIGO data, between 20 and 100 Hz, much of which was not explored in initial LIGO. The search was made possible by the computing power provided by the volunteers of the Einstein@Home project. We find no significant signal candidate and set the most stringent upper limits to date on the amplitude of gravitational wave signals from the target population, corresponding to a sensitivity depth of 48.7 …

A Comprehensive Evaluation Of Feature Selection For Gait Recognition Using Smartwatches, N Al-Naffakh, Nathan Clarke, P Haskell-Dowland, Fudong Li

School of Engineering, Computing and Mathematics

Activity recognition that recognises who a user is by what they are doing at a specific point of time is attracting an enormous amount of attention. Whilst previous research in activity recognition has focused on wearable dedicated sensors (body worn sensors) or using a smartphone’s sensors (e.g. accelerometer and gyroscope), little attention is given to the use of wearable devices – which tend to be sensor-rich highly personal technologies. This paper presents a thorough analysis of the current state of the art in transparent and continuous authentication using acceleration and gyroscope sensors and an advanced feature selection approach to select …

Copula And Vine Modeling For Finance, L Dalla Valle

School of Engineering, Computing and Mathematics

No abstract provided.

Formation Of One-Part-Mixing Geopolymers And Geopolymer Ceramics From Geopolymer Powder, Yun Ming Liew, Cheng Yong Heah, Long Yuan Li, Nur Ain Jaya, Mohd Mustafa Al Bakri Abdullah, Soo Jin Tan, Kamarudin Hussin

School of Engineering, Computing and Mathematics

No abstract provided.

In Vitro Toxic Effects Of Reduced Graphene Oxide Nanosheets On Lung Cancer Cells, Ta Tabish, Mzi Pranjol, H Hayat, Aam Rahat, Et Al

School of Engineering, Computing and Mathematics

The intriguing properties of reduced graphene oxide (rGO) have paved the way for a number of potential biomedical applications such as drug delivery, tissue engineering, gene delivery and bio-sensing. Over the last decade, there have been escalating concerns regarding the possible toxic effects, behaviour and fate of rGO in living systems and environments. This paper reports on integrative chemical-biological interactions of rGO with lung cancer cells, i.e. A549 and SKMES-1, to determine its potential toxicological impacts on them, as a function of its concentration. Cell viability, early and late apoptosis and necrosis were measured to determine oxidative stress potential, and …

Tensorviz: Visualizing The Training Of Convolutional Neural Network Using Paraview, Xinyu Chen, Qiang Guan, Xin Liang, Li-Ta Lo, Simon Su, Trilce Estrada, James Ahrens

Computer Science Faculty Research & Creative Works

Deep Convolutional Networks have been very successful in visual recognition tasks recently. Previous works visualize learned features at different layers o help people to understand how CNNs learn visual recognition tasks. However they do not help to accelerate the training process. We use Paraview to provides both qualitative and quantitative visualization that help understand the learning procedure, tune the learning parameters and direct merging and pruning of neural networks.

Tensorviz: Visualizing The Training Of Convolutional Neural Network Using Paraview (Poster), Xinyu Chen, Qiang Guan, Xin Liang, Li-Ta Lo, Simon Su, Trilce Estrada, James Ahrens

Computer Science Faculty Research & Creative Works

Deep Convolutional Networks have been very successful in visual recognition tasks recently. Lots of previous works aimed to help people to get senses of why those biology-inspired networks achieved such good performances. Deconvnet[1], Guided propagation[2] and a comprehensive visualization tool box[3] can help people to see features learned at different layers of the networks. These works in some extent provided understanding and support for the biology origin of how convolutional networks emulate visual recognition tasks. However, due to the complexity of searching in very high dimensional parameter space, the whole training remains in black-boxes. Normally a large network needs weeks …

Experimental Design And Robust Regression, Pranay Kumar

Theses

Design of Experiments (DOE) is a very powerful statistical methodology, especially when used with linear regression analysis. The use of ordinary least squares (OLS) estimation of linear regression parameters requires the errors to have a normal distribution. However, there are numerous situations when the error distribution is non-normal and using OLS can result in inaccurate parameter estimates. Robust regression is a useful and effective way to estimate the parameters of a regression model in the presence of non-normally distributed residuals. An extensive literature review suggests that there are limited studies comparing the performance of different robust estimators in conjunction with …

3d Hybrid Model For New Product Development, Nataraj Munoli

Theses

Peter Thiel, in his book Zero to One, mentioned the importance of going from zero to one over one to infinity. The value of innovation and creating a unique product will always hold a higher value than doing something that has already been done. The author explains how the businesses that are unique or have very few competitors tend to be more successful when compared to businesses that offer similar services or products as offered by numerous other businesses. To achieve this edge over the contemporaries, there is a growing need to introduce new products to the market by exploiting …

Boulder Distribution Analysis Of Impact Craters In The Tharsis Region And Elysium Planitia, Mars, Nicole Button

LSU Master's Theses

Crater counting is an accepted method for dating the surface of a planetary body. An older landscape will have a higher areal density of craters due to exposure of impacts occurring over a longer time period. Since each initial impact only forms one primary crater, secondary craters need to be excluded in the crater counting method to appropriately catalog only distinct impact events. However, small primary craters may be difficult to distinguish from secondary craters. Understanding physical features of impact craters, such as the ejecta blanket, would improve the planetary community’s ability to differentiate between the two types of craters. …

Contributor's Notes

Fishladder: A Student Journal of Art and Writing

No abstract provided.

Lunchtime Recess, Cayla Dwyer

Fishladder: A Student Journal of Art and Writing

No abstract provided.

Identifying Impaired State For A Driver, Catherine Cardinal, Cliff Sze

Defensive Publications Series

Generally, the present disclosure is directed to improving driver safety by identifying impaired drivers. In particular, in some implementations, the systems and methods of the present disclosure can include or otherwise leverage one or more machine-learned models to predict a driver’s impairment state based on driving data.

Determining High-Level Topical Annotations For A Conversation, N/A

Defensive Publications Series

Generally, the present disclosure is directed to annotating a conversation with high-level topical annotations. In particular, in some implementations, the systems and methods of the present disclosure can include or otherwise leverage one or more machine-learned models to predict topical annotations for a conversation based on audio data from the conversation.

Determining Projection Format For A Video, N/A

Defensive Publications Series

Generally, the present disclosure is directed to determining one or more projection formats for a video. In particular, in some implementations, the systems and methods of the present disclosure can include or otherwise leverage one or more machine-learned models to predict a projection format for a segment of a video based on image data extracted from the video.

Recommending Items For Deletion Based On Item Quality And Usage, N/A

Defensive Publications Series

Generally, the present disclosure is directed to recommending items stored in a data storage system for deletion. In particular, in some implementations, the systems and methods of the present disclosure can include or otherwise leverage one or more machine-learned models to predict a likelihood of deletion for an item based on item data and user interaction data for one or more items.