Digital Commons Network^™

An Adaptive Approach To Gibbs’ Phenomenon, Jannatul Ferdous Chhoa

Master's Theses

Gibbs’ Phenomenon, an unusual behavior of functions with sharp jumps, is encountered while applying the Fourier Transform on them. The resulting reconstructions have high frequency oscillations near the jumps making the reconstructions far from being accurate. To get rid of the unwanted oscillations, we used the Lanczos sigma factor to adjust the Fourier series and we came across three cases. Out of the three, two of them failed to give us the right reconstructions because either it was removing the oscillations partially but not entirely or it was completely removing them but smoothing out the jumps a little too much. …

Exploring The Relationships Between Mothers' Use Of Food To Soothe, Feeding Type And Mode, Maternal Feeding Style, Infant Behavior, And Infant Weight-Related Outcomes During Early Infancy, Megan K. Hupp

Master's Theses

Rapid infant weight gain (RWG) in the first six months postpartum is a strong predictor for obesity during childhood and adolescence. Although biological factors can influence infant weight gain trajectories, the modifiable factor of parent feeding practices can also have an influence. The use of food to soothe (FTS), or the act of feeding a child when he/she is upset for reasons other than hunger, has been associated with unhealthy eating behaviors and less-favorable weight outcomes in children and older infants. However, limited studies have explored the use of FTS during early infancy before the introduction of solids foods. The …

Low-Cost Reaction Wheel Design For Cubesat Applications, Nicholas J. Bonafede Jr.

Master's Theses

As science instruments on CubeSats become more sensitive to the attitude of the spacecraft, better methods must be employed to provide the accuracy needed to complete the planned mission. While systems that provide the accuracy required are available commercially, these solutions are not cost-effective, do not allow the design to be tailored to a specific mission, and most importantly, do not give students hand-on experience with attitude control actuators. This thesis documents the design, modeling, and simulation of a low-cost, student-fabricated, reaction wheel system for use in 3U CubeSat satellites. The entire design process for the development of this reaction …

Traffic Privacy Study On Internet Of Things – Smart Home Applications, Ayan Patel

Master's Theses

Internet of Things (IoT) devices have been widely adopted in many different applications in recent years, such as smart home applications. An adversary can capture the network traffic of IoT devices and analyze it to reveal user activities even if the traffic is encrypted. Therefore, traffic privacy is a major concern, especially in smart home applications. Traffic shaping can be used to obfuscate the traffic so that no meaningful predictions can be drawn through traffic analysis. Current traffic shaping methods have many tunable variables that are difficult to optimize to balance bandwidth overheads and latencies. In this thesis, we study …

Assessing Undergraduate Sustainability Knowledge At California Polytechnic State University, Elysa C. M. Briens

Master's Theses

Sustainability education has become an important focus of many higher education institutions (HEIs), with the inclusion of many sustainability-related learning objectives for undergraduate students. As sustainability is a new, rising discipline, an increasing number of HEIs have made efforts to assess their teaching and learning effectiveness. However, most assessments fall short in determining the relationship between sustainability curriculum and the impacts on leaning outcomes. Therefore, this study aims to assess the impact of academic setting, specifically of a structured sustainability curriculum, on undergraduate sustainability knowledge, as well as analyze the implications of perceived barriers and opportunities to implementing sustainability into …

Pathfinding Interplanetary Bus Capability For The Cal Poly Cubesat Laboratory Through The Development Of A Phobos-Deimos Mission Concept, Alyssa M. Ralph

Master's Theses

With the rise of CubeSats and the demonstration of their many space applications, there is interest in interplanetary CubeSats to act for example as scientific investigations or communications relays. In line with the increasing demand for this class of small satellites, the Cal Poly CubeSat Lab (CPCL) seeks to develop a bus that could support an interplanetary science payload. To facilitate this, a mission concept to conduct science of the moons of Mars, Phobos and Deimos, is investigated by determining the mission needs for a CubeSat in a Phobos-Deimos cycler orbit through the development of a baseline design to meet …

The Role Of Potential For Interaction In Parasocial Relationships, Aaron Bermond

Master's Theses

Previous research suggests that individuals can develop parasocial relationships, or strong emotional attachments to figures in the media. While these relationships typically only involve a one-way exchange of information (target to viewer), viewers still receive many positive benefits that are typical of friendships and other interpersonal bonds. The current literature on parasocial relationships provides detailed information on why they are formed, who forms them, and why they are useful, yet no research has investigated whether the potential for interaction between a media figure and a viewer moderates their psychological effects. We proposed that the most beneficial types of parasocial relationships …

Marketing To The New Generations Of Lgbtq+ Tourists, George Smith

Master's Theses

As social acceptance for LGBTQ+ people grows, it is essential to research and understand more about tourism and its important role in the lives of LGBTQ+ populations. There are tourism communities around the country that may not be familiar with this market segment and are not sure where to start. This can leave the LGBTQ+ market segment under-represented in the tourism industry. This research sets out to answer the question, “Can tourism communities who wish to expand to newer generations of LGBTQ+ travelers market to them successfully?” Mixed research methods include an exploration of city tourism websites, interviews with tourism …

Alveolar Bone And Airway Changes In Different Maxillary Expansion Treatments: A 3d Cone-Beam Tomography Study, Dennis Wang

Master's Theses

Objectives: To evaluate the long-term effects on the airway and bone in patients that have undergone BA, TA and control with 3D cone beam computed tomography (CBCT) analysis. Materials and Methods: 180 CBCTs were analyzed for 60 patients at pretreatment (T1), post expansion (T2), and post-treatment (T3). Patients were divided into three groups, bone anchored expansion (BA), tooth anchored expansion (TA) and a control group. For the airway portion of the study, the nasal cavity, nasopharyngeal, oropharyngeal and laryngopharyngeal, and total airway volumes were measured. Total airway area, minimal cross-sectional area, maxillary intermolar, external maxillary and palatal widths were also …

Interprofessional Collaboration For Oral Health Education And Screening Of Children With Special Health Care Needs, Lamia Habib

Master's Theses

In 2016, National Survey of Children’s Health conducted by the U.S. Department (HRSA MCHB) identified 18.8% of children aged 0-17 years old with Special Health Care Needs (CSHCN). Of these children, 83.4% are not receiving adequate healthcare. It has been well established that oral health is an integral part of the child’s general health. Medical primary care physicians may play an important role in improving oral health outcomes through oral screening, referral, oral health education and promotion. CSHCN may be at an increased risk for oral health problems throughout their life which may negatively impact their quality of life and …

Evaluation Of Obturation Extrusion Of Guttacore With Varying Insertion Rates, John Barrett

Master's Theses

Abstract:

Introduction:The aim of this study is to determine whether the insertion rate of the Dentsply/Sirona Guttacore obturation product with Dentsply AH Plus sealer has an effect on 1. the extrusion amount of the obturating materials and 2. the extrusion probability of the obturating materials out of root canal apex.

Methods:Thirty root canal simulating plastic blocks were prepared with Waveone Gold nickel titanium rotary files to a size “primary” file. The prepared blocks were divided into three groups: group 1 was obturated using GuttaCore size primary obturator (analogous to the reciprocating file size) at a rate of 1 …

Assessment Of The Effects Of Malaria And Anemia In Pregnant Malawian Women Before And After Treatment Of Moderate Malnutrition, William Shipley

Master's Theses

ABSTRACT

Assessment of the Effects of Malaria and Anemia in Pregnant Malawian Women Before and After Treatment of Moderate Malnutrition

William Shipley

Background: Moderate acute malnutrition (MAM) can lead to adverse maternal and infant outcomes and possibly further complications. Supplementary foods or treatments with high quality nutrients should be administered to those with MAM in hopes to increase the chance of healthy maternal and infant outcomes. Sometimes supplementary food is not enough to overcome MAM and disease may play a role, particularly in pregnant malnourished women.

Objective: To determine if the effects of malaria and anemia moderated the effect of …

Fast Asymptotic Algorithm For Real-Time Analysis Of Multivariate Systems And Signals By Directed Transfer Function And Partial Directed Coherence Measures Of Connectivity, Farnaz Rezaei

Master's Theses

Connectivity Granger-causality measures in the frequency domain, such as the Directed Transfer Function (DTF) and Partial Directed Coherence (PDC) and their variants, constitute a family 𝜙 of measures that stem from the modeling of multidimensional time series by multivariate autoregressive (MVAR) models. 𝜙 measures have become popular for evaluation of causal interactions in neuronal networks. Surrogate and asymptotic statistical analysis are the two most frequently used methods to quantify the statistical significance of the derived interactions, a critical step for validation of the results. Each method has its own pros and cons, with the recently published asymptotic methodology being faster. …

Limitations Of Initial Orbit Determination Methods For Low Earth Orbit Cubesats With Short Arc Orbital Passes, James P. Johnson

Master's Theses

This thesis will focus on the performance of angles only initial orbit determi- nation (IOD) methods on observational data of low Earth orbit (LEO) CubeSats. Using data obtained by Lockheed Martin’s Space Object Tracking (SpOT) facil- ity, four methods: Gauss, Double-R, Gooding and Assumed Circular, will use different amounts of orbital arc to determine which methods perform the best in the short arc regime of less than 10 degrees of orbital arc. Once the best method for estimating the orbit is determined, there will be analysis on whether these IOD methods are accurate enough to predict a secondary observation session. …

Identification Of Users Via Ssh Timing Attack, Thomas J. Flucke

Master's Theses

Secure Shell, a tool to securely access and run programs on a remote machine, is an important tool for both system administrators and developers alike. The technology landscape is becoming increasingly distributed and reliant on tools such as Secure Shell to protect information as a user works on a system remotely. While Secure Shell accounts for the abuses the security of older tools such as telnet overlook, it still has fundamental vulnerabilities which leak information about both the user and their activities through timing attacks. The OpenSSH client, the implementation included in all Linux, Mac, and Windows computers, sends each …

Feeling Out Your Food: A Histological Analysis Of The Whisker System In Seals, Cameron Cooper

Master's Theses

The vibrissal (whisker) system is present in nearly all mammals and is especially important in deep-diving mammals. Pinnipeds (seals, sea lions, and walruses) have highly sensitive whiskers that are used to follow hydrodynamic trails created by their swimming prey. Each pinniped vibrissa is surrounded by a tripartite blood sinus system composed of an upper cavernous sinus (UCS), a ring sinus (RS), and a lower cavernous sinus (LCS). The UCS has been hypothesized to play a thermoregulatory role, insulating temperature sensitive mechanoreceptors located within the vibrissal follicle. The aim of this study was to examine this hypothesis by measuring and comparing …

Context Effects On Child Object Touch And Parent Referential Speech: Implications For Autism Spectrum Disorder, Amanda Mankovich

Master's Theses

Object play provides a critical setting for early learning (West & Iverson, 2017). Previous research has established a role for context (i.e., type of activity and parent input), in shaping child touch behaviors. Although several studies have investigated the development object play, many miss key characteristics of everyday environments. Using data from the Longitudinal Study of Early Language (Naigles & Fein, 2017), we investigated how play is affected by development, parent input, and engagement in various activities across both typically developing (TD) children and children with autism spectrum disorder (ASD). We analyzed object prompts and independently coded moments toddlers touched …

Symptoms Of Autism Spectrum Disorder And Developmental Delay In Children With Low Mental Age, Rebecca P. Thomas

Master's Theses

No abstract provided.

Towards Security And Privacy In Networked Medical Devices And Electronic Healthcare Systems, Isabel Jellen

Master's Theses

E-health is a growing eld which utilizes wireless sensor networks to enable access to effective and efficient healthcare services and provide patient monitoring to enable early detection and treatment of health conditions. Due to the proliferation of e-health systems, security and privacy have become critical issues in preventing data falsification, unauthorized access to the system, or eavesdropping on sensitive health data. Furthermore, due to the intrinsic limitations of many wireless medical devices, including low power and limited computational resources, security and device performance can be difficult to balance. Therefore, many current networked medical devices operate without basic security services such …

Design Of An Electrospray Thruster Power Processing And Digital Control Interface Unit, Douglas Howe

Master's Theses

Electrospray thrusters are low thrust, high specific impulse electric propulsion devices with applications in precision attitude control of space vehicles and efficient propulsion of small spacecraft platforms. These devices operate by electrostatically extracting particles from the surface of ionic liquid propellants and accelerating them away from the vehicle at high speed. Unlike more conventional propulsion technologies which only require electronics for control and regulation, electrospray thruster systems require extensive electronics to operate. The power processing unit (PPU) is a device used to produce the high voltage levels required to operate an electrospray thruster and to measure its operating parameters. The …

Fast Chirped Signals For A Tdma Ultrasonic Indoor Positioning System, Lauren M. Williams

Master's Theses

In this paper, a new concept for ultrasonic indoor positioning based on instantaneous frequency of ultrasonic signals is presented. Nonlinear phase characteristics of ultrasonic transducers introduce a frequency deviation in ultrasonic signals. By sweeping at very fast rates, a large spike in the deviation is introduced. The artefacts observable in instantaneous frequency estimations are highly localized and present an opportunity for accurate frequency detection. In order to be useful, the artefacts need to take place within the pulse and have sufficient magnitude for accurate processing. The system consists of a transducer transmitter and receiver pair, which have a center frequency …

Writing For Each Other: Dynamic Quest Generation Using In Session Player Behaviors In Mmorpg, Sean Christopher Mendonca

Master's Theses

Role-playing games (RPGs) rely on interesting and varied experiences to maintain player attention. These experiences are often provided through quests, which give players tasks that are used to advance stories or events unfolding in the game. Traditional quests in video games require very specific conditions to be met, and for participating members to advance them by carrying out pre-defined actions. These types of quests are generated with perfect knowledge of the game world and are able to force desired behaviors out of the relevant non-player characters (NPCs). This becomes a major issue in massive multiplayer online (MMO) when other players …

Initial Orbit Determination Error Analysis Of Low-Earth Orbit Rocket Body Debris And Feasibility Study For Debris Cataloguing From One Optical Facility, Kyle Stoker

Master's Theses

This paper is predicated on determining the effectiveness of angles-only initial orbit determination (IOD) methods when limited observational data is available for low-Earth orbit (LEO) rocket body debris. The analysis will be conducted with data obtained from Lockheed Martin Space’s Space Object Tracking (SpOT) facility, focusing on their observational data from 2018 that contains tracking of rocket body debris for less than one minute per overhead pass. After the IOD accuracies are better understood, a feasibility study will follow that investigates the possibility of cataloguing LEO orbital debris from a single optical observation facility with similar observational capabilities as that …

Design Of A Custom Wrist Brace That Can Be 3d Printed From A Three-Dimensional Scan, James D. Baldwin

Master's Theses

Current arm bracing and casting methods for distal forearm and wrist fractures can lead to varying negative medicinal affects such as tightness, skin breakdown and bacteria growth which can cause infection. This can be alleviated by a flexibly compliant and breathable design while keeping the arm and hand fixed at the wrist to promote proper wrist and forearm fracture healing. There have been attempts made to create a 3D printable brace from a three-dimensional scan but they do not account for full encapsulation of the wrist, removability without breaking the brace, nor for the brace being too tight and leading …

Investigation Of Experimental Variation Of Bovine Sphingomyelin As A Novel Ingredient For Ultraviolet Protection, Esther Chen

Master's Theses

Skin cancer is a prevalent disease that globally affects 2-3 million people per year [1]. This number is expected to grow tenfold as depletion of the ozone layer contributes to harsher rays reaching Earth’s surface [2]. A common way to protect against those ultraviolet waves is to apply sunscreen, however, recent reports call into question the safety of some active ingredients as they can enter through the skin into the bloodstream [3]. This thesis aims to investigate an alternative solution that uses bovine sphingomyelin (BSM) as photoprotective solution against UV irradiation.

In order to evaluate the effectiveness of BSM against …

Pocket Rocket: A 1u+ Propulsion System Design To Enhance Cubesat Capabilities, James M. Harper

Master's Theses

The research presented provides an overview of a 1U+ form factor propulsion system design developed for the Cal Poly CubeSat Laboratory (CPCL). This design utilizes a Radiofrequency Electrothermal Thruster (RFET) called Pocket Rocket that can generate 9.30 m/s of delta-V with argon, and 20.2 ± 3 m/s of delta-V with xenon. Due to the demand for advanced mission capabilities in the CubeSat form factor, a need for micro-propulsion systems that can generate between 1 – 1500 m/s of delta-V are necessary.

By 2019, Pocket Rocket had been developed to a Technology Readiness Level (TRL) of 5 and ground tested in …

Host Plant Resistance In Strawberries To Anthracnose And Colonization Of Crown And Root Tissue By Verticillium Dahliae And Macrophomina Phaseolina, Omar A. Gonzalez-Benitez

Master's Theses

Strawberries are considered an important crop in California where in 2018 it was in the top 5 valued fruit and vegetable commodities valued at $2.84 billion accounting for 88% of the total U.S. production. Strawberry production can be severely impacted by soilborne pathogens that can affect strawberry roots, crowns and leaves which can result in plant mortality. As much as 50 to 60% mortality can occur in one field. Pathogens responsible for such losses include Colletotrichum acutatum (syn.C. nymphaeae), Macrophomina phaseolina and Verticillium dahliae. With the phaseout of methyl bromide, host resistance and an understanding of host-pathogen interactions …

The Strawberry Rhizosphere Microbiome: Role On Plant Health And Nutrition, Eric Michael Boyd

Master's Theses

Microbial-root associations are important to help plants cope with abiotic and biotic stressors. Managing these interactions offers an opportunity for improving the efficiency and sustainability of agricultural production. By characterizing the bacterial and archaeal community (via 16S rRNA sequencing) associated with the bulk and rhizosphere soil of sixteen strawberry cultivars in two controlled field studies, we explored the relationships between the soil microbiome and plant resistance to two soilborne fungal pathogens of strawberry (Verticillium dahliae and Macrophomina phaseolina). Overall, the plants had a distinctive rhizosphere microbiome relative to the bulk soil, with higher abundances of known beneficial bacteria …

Barriers To Success: Sheep And Goat Producers In The Service-Grazing Industry, Erin A. Campbell-Craven

Master's Theses

Service-grazing is a novel term for grazing done on land not owned or rented by a livestock producer or manager, for the purpose of land management, and for which the owner or land manager receiving grazing services pays compensation to the service provider. This research project seeks to gather detailed information about producers in the Western United States, providing grazing services under this project’s definition of “service-grazing”, with a focus on those operating in California, in order to discover the business models or practices necessary to be successful within a service-based grazing operation. To this end, an online survey consisting …

Mindfulness For Stress Reduction: Qualitative Analysis Of Perceptions From College Students And Mindfulness Instructors, Beth Marie Merlo

Master's Theses

Although mindfulness interventions with college students have yield positive results, many students are not continuing to engage after the interventions. This may be because very little research has been done to investigate the health behavior beliefs of college students in regard to mindfulness for stress reduction. The purpose of this investigation was to identify the most influential components of the Integrated Behavioral Model (IBM) that potentially assist with predicting college student participation in mindfulness activities for stress reduction. Interviews, informed by the IBM, were conducted with 20 current college students and 5 current mindfulness instructors working with college students. The …