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Failure Behavior of Woven Fiberglass Composites Under Combined Environmental and Mechanical Compressive Loading
No full textWoven fiber reinforced polymers are often utilized in naval aircraft structures, where they are valued for their weight reduction with comparable strength to traditional metals. Frequent aircraft launch and landing cycles, as well as defensive maneuvers can load polymer matrix composites (PMCs) under complex, multi-temporal conditions. In addition, extended exposure to seawater in a naval setting can result in water uptake, causing swelling and potentially corrosion to the matrix and fiber-matrix interfaces. The purpose of this study is to quantitatively and systematically characterize the compressive behavior of fiberglass PMCs under combined mechanical and environmental loading, in order to develop more predictive damage evolution models under realistic conditions. Cuboidal samples of G10 garolite, a commercially available epoxy resin woven fiberglass, are used as a model material to examine uniaxial compressive loading perpendicular to the plies under both quasi-static (10^-3 s^-1) and dynamic (10^3 s^-1) strain rates. In order to simulate environmental conditions, certain samples were soaked in either distilled or ASTM standard seawater prior to loading. Two periods of time of environmental conditioning were considered, short term at two weeks, and long term at four months. Results demonstrate that, on average, the dynamic compressive strength of the composite increased 35% from the quasi-static. Moreover, environmentally treated samples generally experienced a decrease in strength, but higher strain to failure, and composites exposed to water for only short periods exhibited signs of the absorbed water sustaining additional load within the material. Ultra high-speed photography along with the full-field imaging technique of digital image correlation (DIC) was used to obtain in-situ full-field strain maps. In all cases, a clear shear band failure mechanism from local instabilities at the tow can be seen, and a Mohr-Coulomb failure criterion is used to extract a mesoscale cohesive shear stress and coefficient of internal friction. The shear failure behavior was also quantified in terms of the rate and speed of formation per loading condition examined.M.S., Mechanical Engineering and Mechanics -- Drexel University, 201
Determining the Optimum Duration of User Interface Animation In Microinteraction Design: Comparing Mouse vs. Touch Input
No full textUser Interface animation has been increasingly designed into various interactive interfaces in recent years, including web and mobile-based interface. Using a variety of animation effects, things are easier to understand, the mood is boosted, and the boring state becomes more interesting. However, only well-designed animation can bring users a better experience than a simple static interface. Studies have shown that animation duration would be an important mechanics affecting animation design, and the same animation duration perceived in mouse and touch input screens may differ. In this study, we designed an animated interface duration survey to allow users to perceive different interface animations with the different duration applied on a menu and compare participants’ selections. The main focus is to evaluate how different factors affect users to perceive interface animation durations and whether or not there’s a perceived difference in optimum user interface animation duration across device input types. We described how we designed a testing tool which is a responsive website in research method. We conducted a testing of 25 participants and presented the data showing the results on how they perceived the UI animation durations. We found that users tend to be similar in the perception of different styles of UI animation. Moreover, we proposed that input mode, gender, age, reaction time and design experience don’t explicitly affect user’s perception of UI animation duration. By analyzing quantitative and qualitative data, we found out the minimum and maximum value of the duration difference. Within this range, a UI animation duration could be perceived properly. We suggested the further study can be conducted in a content-based commercial environment which we believe the results would be more practical. This study hopes that it can provide helpful guides when designing animation for both mouse and touch input UIs.M.S., Digital Media -- Drexel University, 201
Enhancing Cultural Awareness and Sensitivity Through Theatre and Language Education
No full textThis study examines the social and cultural effects of using theatre in the context of the K-12 second language classroom. Using personal experience and the experience of 10 language educators, I have compared and contrasted a variety of accepted language learning pedagogies to determine whether or not students can become more culturally aware by having theatre incorporated into their language classes. I found that by doing so, children are likely to be more open and accepting of different cultures, traditions and people different from themselves because they will have taken a walk in another’s shoes. This thesis seeks to advance the conversation so that we as educators can create and sustain the best practices in language learning in pursuit of broader intercultural understanding particularly in a highly polarized political environment.
Abstract (Spanish)
Este estudio examina los efectos sociales y culturales del uso del teatro en clases de idiomas secundarias para niños entre K-12. Usando mi experiencia personal y la experiencia de 10 profesores de idiomas, comparé y contrasté una variedad de pedagogías de aprendizaje de idiomas aceptadas para determinar si los estudiantes pueden o no ser más conscientes de la cultura al tener teatro incorporado en sus clases de idiomas. Descubrí que al hacerlo, es probable que los niños sean más abiertos y acepten diferentes culturas, tradiciones y personas diferentes a ellos mismos porque habrán caminado en los zapatos de otra persona. Esta tesis busca avanzar en la conversación para que nosotros, como educadores, podamos crear y sostener las mejores prácticas en el aprendizaje de idiomas en busca de una comprensión intercultural más amplia, particularmente en un entorno político altamente polarizado.M.S., Arts Administration -- Drexel University, 201
Disaster Preparedness and Recovery: Assessing the Needs of Individual Artists During Hurricane Harvey
No full textThis thesis explores the impact of natural disaster on individual artists in Houston, Texas after Hurricane Harvey in 2017. Included is an analysis of current artist preparedness and recovery policy, a review of resilience strategy, interviews with Houston-based artists, and interviews with the Harvey Arts Recovery Fund (HARF), an arts recovery group created in response to Hurricane Harvey. These sources provide evidence to show that professional artists often experience multiple layers of loss due to disaster, including loss of income, loss of tools and materials, loss of artwork, loss of studio and residential space, and emotional loss. Because artists often sustain damages to both their living and work spaces at the same time, there is also evidence to show that individual artists require additional assistance in creating more comprehensive personal preparedness plans. This thesis provides recommendations to better assist artists in preparedness and recovery based on resilience strategy, the HARF model, and key takeaways collected from artists who have experienced disaster.M.S., Arts Administration -- Drexel University, 201
A Second Chance: A Phenomenological Study of African American Student Perceptions of Urban Secondary Alternative Schools
No full textMany urban school districts in the United States now offer students nontraditional placement options. The alternative school is an option for students who have dropped out of the traditional high school, have academic or behavioral challenges or have been expelled. As African American students in urban school districts are currently overrepresented in alternative schools, the problem this study addressed was the need to better understand the lived experiences of African American students in these settings. The study specifically focused on 18-24-year-old students and examined how their perceptions of the school environment, their educational opportunities and their teachers impacted their achievement, motivation and educational outcomes. To capture diverse perspectives, participants were selected from two alternative schools in a large urban school district in the Northeast region. Data were collected through one on one and focus group interviews, classroom observations and field notes. Through an examination of the lived experiences and perceptions of African American students in these settings, the researcher endeavored to understand whether alternative high schools are meeting African American students' educational needs. The research questions that were examined are: (1) How do African American students in urban secondary alternative schools describe their lived experiences related to success, empowerment and motivation, (2) How do African American students in urban secondary alternative schools perceive the environment/culture and the educational opportunities available to them, and (3) How do African American students in urban secondary alternative schools describe the teachers who push them to excel and succeed? The six emerging themes from this study were: a) maturity and self-advocacy; b) a better opportunity/a positive climate; c) feeling respected and heard; d) it takes a village; e) relevant and rigorous instruction; and f) absence of discontinuity. Study participants reported that caring and supportive relationships with teachers, staff and administrators, a positive school climate and multiple options and resources in alternative schools have helped them to overcome challenges that they face. The participants also noted culturally responsive teaching, school cohesion and cultural congruity as factors which contribute to their motivation and success and keep them on track to graduate despite obstacles that they encounter.Ed.D., Educational Leadership and Management -- Drexel University, 201
Promoting Kinesthetic Empathy with Dance/Movement Therapy: An Evidence- Informed Protocol to Support De-escalation
No full textThe purpose of this capstone is to develop and implement an evidence-informed practice protocol that promotes kinesthetic empathy in de-escalation practice in inpatient psychiatric care. The protocol will be developed as a one-hour in-service and be implemented on an inpatient psychiatric unit in an urban university medical center. Foci within the in-service include kinesthetic empathy, self-awareness, non-verbal communication, somatic countertransference, and identification of early warning signs of aggression. Relevant literature and research will be included to help inform the process and guide the protocol formation as well as reflections on participants’ experiences of the in-service following its implementation. The literature review includes research studies and theoretical articles examining de-escalation trainings, psychiatric nurses’ emotional experiences of patient violence, the effects of burnout on empathy, and dance/movement therapy skills including mirroring, attunement and clashing, and kinesthetic empathy. The protocol was developed to address identified limitations within psychiatric nursing literature, however is also beneficial to other mental health staff. It seeks to support and emphasize body-related aspects of de-escalation practice to bolster staff’s body awareness, empathy, and non-verbal cues of both themselves and others. Sections detailing the experience of staff who attended and participated in the in-service experience will be included, highlighting their past experiences of de-escalation and their efforts to improve their process. The method will show how a dance/movement therapy informed supplemental de-escalation in-service can help mental health staff implement kinesthetic empathy into their de-escalation process.M.A., Dance/Movement Therapy and Counseling -- Drexel University, 201
Acidity of Plasma Activated Water from Non-Equilibrium Plasma Discharges and Identification of Superoxide and Ozonide as the Conjugate Bases of Metastable Plasma Acid
No full textWhen liquid water is treated with a non-thermal plasma discharge, a solution of reactive species is generated, also referred to as plasma activated water (PAW). For some time now, interest in non-thermal plasma treatment of liquids has been increasing in the biomedical, environmental, and agricultural fields as well as food processing. PAW solutions are sought after as advanced oxidative procedures for their oxidizing potential, ease of implementation, and wide range of reactive species produced (e.g., ∙OH, ∙O, H2O2, NO3-, ONOO-). These discharges can be applied near room temperature and atmospheric pressure with a variety of gases including atmospheric air. However, applying non-equilibrium discharges in oxygen or oxygen/noble gas mixtures has been shown to produce acidic solutions. The resulting acidic water solution, sometimes referred as "plasma acid", was shown to have strong but temporary oxidizing properties. The conjugate base of this oxygen plasma-produced acid remained unidentified, while existence of strong temporal water-based oxidizer offers a number of exciting potential applications. At the same time, the applicability of chemical processes observed in treatments with low power discharges used in laboratory setting non-equilibrium plasmas to higher powered discharges for upscaling to industrial needs is still not fully understood. The occurrence of acidic solutions produced from discharges in both air and oxygen environments as well the temperature dependence on the production of reactive nitrogen and oxygen species (RONS) in water were investigated in this study. The results obtained for the water treated with oxygen plasmas suggest that "plasma acid" contains unstable O2- and O3- as possible sources of the "plasma acid" anion which explains the nature and the temporary oxidizing properties of "plasma acid". Production of PAW from a gliding arc plasmatron (GAP) and with nanosecond-pulsed dielectric barrier discharge (DBD) batch treatments are used to investigate the viability of increasing power for the upscaling from laboratory to industrial settings. GAP was a source of "warm" plasma for continuous production useful to an industrial setting, while DBD was a source of cold plasma typically used in laboratory settings and direct biomedical applications. The GAP was shown to produce comparable PAW solution compositions to DBD (specifically HNO3, HNO2, H2O2, and pH), despite the increased power and elevated gas temperatures, largely attributed to the rapid cooling of the solution post treatment.Ph.D., Mechanical Engineering and Mechanics -- Drexel University, 201
A Systems Approach to Modeling and Simulating Cellular Stochasticity and Adaptation Across Multiple Biological Scales
No full textTo understand the behavior of biological systems we need to consider that they are made of populations of individual cells. The behavior of these cells is also dependent on the interactions of multiple organelles and protein complexes. Every response is dependent on interactions of cells across multiple scales from the molecular through the level of the organelle, the cell and then to cell-cell interactions. To look at these cells across different biological scales, with a systems approach, we need to develop mathematical models and simulations that allow us to consider biological interactions at different scales and across scales. Creating such multi scale models of molecular and cellular dynamics was the heart of my thesis. To do so I pursued 3 aims: 1) I conducted statistical and model-based analysis of imaging experiments at both the cellular and organelle biological scales 2) I developed TIPS, a stochastic modeling framework for tracking of individual agent kinematics through complex binding to model and simulate cellular behavior at the molecular scale. I applied TIPS to simulate Calcium dependent STIM and Orai binding and motion. 3) I developed MiGHT a multi-scalar stochastic modeling framework for the simulation of cellular adaptation and utilized this framework to model the interconnected networks of cellular behavior across multiple biological scales. I used MiGHT to model and simulate the macrophage response to lipopolysaccharide, specifically modeling how the macrophage response adapts to the cytokine environment through the modeling of cellular behavior across the molecular, cellular, and systemic biological scales. Here, my thesis provided a way to approach taking experimental data to single scale models and simulations to interconnected multi-scalar models and simulations. In doing so, this work has provided a way in which we can model and simulate how perturbations at molecular scales, such as genetic alterations or drug administration, can impact cellular and systemic behavior.Ph.D., Biomedical Science -- Drexel University, 201
Functional Properties and Allergenicity of Low Molecular Weight Protein Fractions Recovered from EAEP of Soybeans
No full textFood waste leads to wastage of food resources and severe environmental problems, such as land depletion, water pollution, and greenhouse gas emissions. In addition, certain disposal standards need to be achieved before discarding, non-biodegradable and materials harmful to the environment. Therefore, appropriate utilization of food waste will help divert food waste from landfills and reduce environmental damages at the same time. Enzyme-assisted aqueous extraction process (EAEP) is an environmentally friendly oil extraction process, but the extension of this process is limited due to the high enzyme costs. Soybean EAEP wastes, soy skim, is a rich protein source. The aim of this study was to characterize soy skim and evaluate its functional properties and allergenicity. Soy skim was analyzed for sugar composition, protein and moisture content. Taste profile of soy skim was determined using e-tongue and allergenicity of different soy skim fractions (>10, 10-5, 5-3, and <3 kDa) was estimated using enzyme-linked immunosorbent assay (ELISA). Functional properties of soy skim were estimated by studying the effect of pH (pH 3, pH 5, pH 7, pH 10) and temperature (20℃, 50℃, 70℃, 90℃), on protein solubility, Surface hydrophobicity (H0), of soy skim was determined using fluorescence method, and emulsification properties (emulsifying activity index, creaming inhibition, emulsion stability) compared with two commercial products, soy protein isolate and soy protein concentrate. Protein content of soy skim is 43.8 mg/mL with majority of the proteins having molecular weights lower than 25 kDa; 3-5 kDa fraction has the lowest allergen level than the other sample fractions. Protein in soy skim were found to stable in neutral environment compared to acid environment. Soy skim has higher richness and umami flavor, and lower bitterness and astringency levels compared to soy protein isolate, soy protein acid hydrolysate, and soy protein concentrate. Soy skim has high emulsion stability but low emulsifying activity. These desired sensory and functional properties of soy skim indicate potential of soy skim as a high value food ingredient.M.S., Food Science -- Drexel University, 201
Equity in Public Funding for Arts and Culture in Philadelphia
No full textIs the distribution of public arts funding in Philadelphia equitable? Despite the ascendance of diversity, equity, and inclusion as a sector-wide goal and anecdotal evidence of equity issues in the distributive patterns of both foundation and government grantmaking, issues of distributive equity in US philanthropy have been little studied. What research does exist paints a picture of affluent, white, Eurocentric arts nonprofits dominating the funding landscape to the detriment of small, underrepresented, or otherwise marginalized arts nonprofits. By their mandate, government funders should be more accessible to these kinds of organizations, but are they? In Philadelphia a unique tool exists in CultureBlocks, a website that maps public arts grantees against Census-derived demographic data. Using this tool, the question of the distributive equity of public arts funding in Philadelphia was explored statistically via four different equity standards from the geography literature. While this study could not conclusively affirm or deny that public arts funding in Philadelphia from 2007-2015 was distributed equitably, the data showed no significant correlations between the demographics of a particular area (as a proxy for the demographics of the organizations in that area) and the average percentage of public arts funding received by the arts nonprofits in that area. This lends credence to claims that public arts funding is generally more accessible to small and underrepresented arts organizations, and so may be distributed more equitably, but more research needs to be conducted to fill the research gap. The hope is that this study creates more avenues to further that conversation.M.S., Arts Administration -- Drexel University, 201