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Examining the Use of Digital Marketing Tools Among Visual Artists for Purposeful Career Development
No full textWith the advent of the digital age, visual artists are in a greater position to define their methods of engagement with potential audiences through digital marketing. This engagement helps in creating a digital presence in support of their work and services. Through the combination of a qualitative survey and individual interviews, my research considers how visual artists are implementing digital marketing tools to assist with their career development. In addition to their individual practices, my research identifies the perspective of these artists when even considering the use of these tools. These artists and their combined efforts from digital and traditional marketing sources provide the foundation for this research. It is my belief that an artist's level of awareness and activity of these sources can help determine the value of digital marketing for their professional objectives. Understanding these objectives by their approach, viewpoints, experiences and circumstances can aid with understanding the potential sustained impact of digital marketing for the visual artist community at large. In my findings, I determine that the best approach for artists is to create a strategy that aligns with their professional objectives. With this strategy in place, visual artists are better equipped to identify if any digital marketing tools are ideal for their strategy. This approach allows for learning and experimentation with new media, while limiting valuable time and effort deducted from the creative process.M.S., Arts Administration -- Drexel University, 201
Study on Stabilization of Organo-Halide Perovskite Particles in Aqueous Suspensions
No full textOrganometallic-halide perovskite has been intensively studied for its potential applications in solar cells, LED and display due to the optoelectronic properties related to their nanometer sizes. For example, the perovskite MAPbBr3 has demonstrated very good photoluminescent properties and has great potential for biological imaging and detection. However, the fact that perovskite can be damaged by water hinders their use in the hydrophilic aqueous environment. Motivated by the excellent photoluminescent properties of MAPbBr3 nanoparticles, the goal of the thesis is to develop a stable aqueous MAPbBr3 suspensions for the potential bioimaging applications. The present work studies the use of amphiphilic copolymer PMAO-PEG (Poly(maleic anhydride-alt-1-octadecene)-polyethylene glycol) in encapsulating perovskite particles to form an emulsion that can be stable in water with time. The perovskite of interest is MA0.4OA0.6PbBr3, (methylammonium/octylammonium lead bromide) which has a hydrophobic surface due to the long alkyl chains acting as intrinsic capping molecules. The results obtained in this work enable perovskite particles to stay in an aqueous environment in the form of oil droplets while maintaining its photoluminescence property for a period of time without significant emission wavelength shift. Single-phase emulsion can retain photoluminescent property for more than 30 minutes with good emulsion stability, on the other hand, perovskite can be stable in the multi-phase emulsions for more than 10 days.M.S., Materials Science and Engineering -- Drexel University, 201
Developing Isocyanide Methodology
No full textIsocyanides are privileged structures, found in bioactive compounds derived from natural sources and pervasive in the synthesis of pharmacologically relevant compounds. Isocyanide synthesis is, however, limited by few commercial products and a dearth of methodology that allows for their manipulation. To this end, the focus has been on pioneering new methods and substrates. The initial work concentrated on the development of conjugate addition reactions to novel oxoalkeneisocyanides, followed by finding a method to purify difficult-to-isolate isocyanides. This was proceeded by the discovery and development of the first copper-catalyzed radical addition to alkeneisocyanides which tangentially lead to a review of copper(I)-isocyanide complex spectra and structure characteristics. Lastly, applications of Asmic, a novel isocyanide building block, were explored in the synthesis of heterocyclic scaffolds.Ph.D., Chemistry -- Drexel University, 201
Spectrum Awareness Using Bayesian Nonparametric Pattern Recognition
No full textTo accommodate an increasing demand for scarce spectrum resources, dynamic spectrum access (DSA) opens portions of the spectrum currently dedicated to licensed primary users, for access by unlicensed cognitive radio secondary users. A key requirement is that the secondary users do not interfere significantly with the primary users. Previous DSA research focuses on sense-and-avoid spectrum sharing strategies. The secondary user occupies a primary user channel only when it is not in use, and vacates immediately upon detecting primary user transmissions. In this setting, spectrum sensing is intended to provide little information aside from instantaneous primary user spectral-temporal occupancy. However, we anticipate that more adaptive and intelligent spectrum sharing strategies will require more advanced sensing capabilities allowing a secondary user to infer the primary user higher-layer protocol state and behavior. This type of feedback about the primary user will enable a secondary user to optimize its own spectrum access while also monitoring for potential impact to the primary user. In this study, we explore Bayesian nonparametric pattern recognition as a tool for informing intelligent secondary-user DSA strategies. We present a framework for learning and inferring primary user protocol state at the application and MAC layers from simple low-level energy detector features. We demonstrate, using a physical wireless network testbed, how this approach discovers actual primary user application layer protocol states and also detects anomalous primary user behavior caused by secondary user interference. We then extend the spectrum awareness framework to handle several simultaneous primary/secondary traffic flows, of potentially different types, multiplexed together onto a single wireless broadcast medium. We use the multi-flow framework to infer the application-layer states of the interleaved flows directly from observations of the aggregate traffic. In this process we circumvent deinterleaving the transmissions of the component flows, a particularly difficult task in cognitive radio environments with parameter-agile transmitters. We demonstrate the performance of the resulting technique on a network scenario with multiple simultaneous flows carrying different application layer traffic types, both in emulation and on an over-the-air hardware testbed.Ph.D., Electrical Engineering -- Drexel University, 201
Fluid-Structure Analysis of a Collapsible Axial Impeller Pump Cage Design for the Fontan Circulation
No full textOf the thousands of children born each year with congenital heart defects, a small cohort have severe malformations of their cardiac chambers leading to a single ventricle physiology. The current treatment standard is a series of palliative surgeries ending with the Fontan procedure which is characterized by connection of the superior and inferior vena cava to the pulmonary arteries. Though lifesaving, this physiology is plagued by a host of complications such as decreased cardiac output, ventricular dysfunction, and thromboembolism. Current pharmacologic and surgical treatments only slow a patient's progression to premature congestive heart failure. Heart transplantation is a viable option, if patients are able to survive the donor organ waiting period. Mechanical circulatory support devices could provide a promising new treatment strategy, though current blood pumps are not designed to support the unique anatomy and physiology of the Fontan circulation. To address the clinical need, this research utilized computational modeling to evaluate the protective cage (stent) of an intravenously deployed collapsible axial flow pump aimed at improving Fontan hemodynamics. The pump functions by rotating a triple bladed impeller housed within the protective cage of four twisted filaments terminating at a set of diffuser blades. Cage expansion relies on the properties of its material composition whether through stored elastic energy or shape memory effects. Paramount to the success of this device is sustention of the expanded geometry. ANSYS CFX and ANSYS Mechanical were employed to characterize the deformation of cages constructed with nitinol and Bionate 80A while steel was used as a reference material. Eight one way coupled fluid structure interaction simulations per material have been designed to examine the cage surface pressure distribution, stress, strain, and resultant deformation for inlet flow rates of 2 and 4 L/min at impeller rotational speeds of 2000, 3000, and 4000 RPM. Free flow conditions featuring the cage alone were also tested to understand the impact of the impeller domain. To develop the simulation meshes, over 70 computational fluid dynamics simulations were carried out as part of a grid independence study. Mesh quality metrics, including aspect ratio, warping factor, and Jacobian ratio, were satisfied for both fluid and structural meshes. Results were extracted from a set of 24 complete simulations. As theoretically expected, the steel cage produced the lowest maximum deformation on a scale less than a millimeter, while the nitinol cage deformed by several millimeters. Despite nitinol's slight deformation increase, the overall cage geometry was minimally altered. In contrast, the Bionate 80A cage produced drastic deformation on the scale of several centimeters. The rotating impeller simulations generated a wide surface pressure range of 4-34 mmHg compared to the free flow simulations, which resulted in a 19-21 mmHg range. The free flow condition produced a uniform pressure distribution over the cage surface, while the rotating conditions caused high peak pressures at the diffuser blades yet an overall decrease in average pressure. These dramatic differences resulted in a minimum increase of 1.5 times the maximum deformation for the free flow simulations compared to the rotating impeller variants. Nitinol's comparable deformation resistance to steel in combination with improved biocompatibility and its shape memory properties establish nitinol as a promising material for further exploration in this application. The Bionate 80A cage deformation was too large, thus alternative materials with greater stiffness should be sought. To further increase deformation resistance it may prove advantageous to either increase filament thickness or to add a fifth filament. Future work should focus on validation via benchtop testing, and additional simulation conditions, such that deformation trends associated with flow rate and impeller rotational speed can be readily identified.M.S., Biomedical Engineering -- Drexel University, 201
The Effects of Engine Operational Parameters on the Auto-ignition Chemistry of n-Decane in a Compression Ignition Engine Environment
No full textJP-8 is a jet fuel widely used by the U.S. military. The military has called for JP-8 to be used in all internal combustion applications, including compression ignition engines. To understand the combustion of JP-8 in these engines, an accepted procedure is to develop combustion models of simple mixtures of hydrocarbons, called surrogates, and their components. As part of a program to develop such models, the auto-ignition behavior of n-decane in a motored engine has been investigated. In-cylinder pressure was measured to indicate the overall reactivity behavior and quantify the effects of engine operational parameters on the auto-ignition of n-decane. Additionally, exhaust gas composition was analyzed by GC/MS to identify and measure stable intermediate species to deduce the key reaction pathways leading to auto-ignition. Furthermore, a new method that uses only pressure data was proposed and developed to identify the start of combustion. By applying this method, the in-cylinder conditions for pre-ignition point were used to predict the ignition of n-decane. Based on the in-cylinder conditions of pre-ignition point, a general pre-ignition limit line for n-decane was generated, taking dilution of residual gas, equivalence ratio, and compression ratio into account. This pre-ignition limit line will be useful for predicting the pre-ignition initiation during the oxidation of n-decane. Furthermore, it is a proof of the concept "pre-ignition limit line", which may be useful when generalized for all hydrocarbons. The measured species profiles from this study may be used in future work to develop detailed and reduced kinetic models for the auto-ignition and oxidation of JP-8 surrogate fuels.Ph.D., Mechanical Engineering and Mechanics -- Drexel University, 201
Community-Based Masters Project: Creating an Interactive Asset Map of Behavioral Health and Substance Abuse Treatment Providers in Philadelphia
No full textFrom previous studies and courses throughout my graduate career in public health, I have learned that access to mental health care and substance abuse disorders are both significant public health issues throughout the United States. For my Community-Based Masters Project, I researched the availability of non-individual mental health care providers and addiction services in the city of Philadelphia. I was surprised to see the abundance of community, multi-location, and hospital-based services and I did not realized that The Department of Behavioral Health and Intellectual DisAbilities Services already has a compiled list of resources in the past. Using the Community Behavioral Health (CBH) inventory as a guide and findings from own Internet-based searches, I compiled an interactive map that illustrates mental health and addiction service providers in the city, along with important information about the providers and the services offered. The basic idea for the map was modeled for a local Philadelphia organization that works to address parental mental health. This paper provides information about the prevalence of behavioral health conditions in the United States and the city of Philadelphia, what organizations and programs around the country and city are doing to address these conditions, and the process I went through to create the asset map of Philadelphia providers. I discuss how the map can be used and why it is useful, plans for its future, and what I learned through this nearly year-long process of working with Child and Family Connections of Philadelphia.M.P.H., Community Health and Prevention -- Drexel University, 201
Sexting and Fertility: An Intervention on Sexual Communication and Empowerment
No full textIt is well established in the literature that infertility is linked to numerous negative psychological sequelae, including anxiety, depression, stress, and overall distress (Domar, Broome, Zuttermeister, Seibel, & Friedman, 1993; Downey et al., 1989; Downey & McKinney, 1992; Freeman et al., 1985; Mahlstedt et al., 1987). Women report that the medicalization of their bodies and sex lives is a cognitively distressing and often dehumanizing ordeal. Unsurprisingly, both sexual and relationship satisfaction tend to diminish during struggles with infertility (Galhardo, Cunha, & Pinto-Gouveia, 2011; Pepe, & Byrne, 1991). This dissertation examines Let’s Get Sexty!, a technological intervention aimed at improving intimacy and sexual satisfaction among women going through fertility treatment. By conceptualizing sexting (sending or receiving sexually suggestive or explicit messages, images, or photos through electronic means) with their partner as a form of sexual communication by which women undergoing infertility treatment may feel empowered and thereby improve their sexual satisfaction during a timeframe noted to be extremely stressful and challenging for women and couples. This project aimed to examine the connection between sexting, sexual communication, intimacy, and sexual satisfaction through the development and implementation of this intervention. Due to recruitment challenges, it was not possible to assess all study hypotheses. The potential contributors to low recruitment included: sensitivity of the target population, perceptions of risk through online recruitment, and generally negative societal views of sexting. Although the development of this project is informed by research, the intervention challenges the pervasive societal view of sexting as a risky behavior that is associated with poor judgment. In addition to challenging women to connect with their sexuality during what is often a dehumanizing ordeal, this project also challenges people to overcome the prevailing view of sexting as dangerous. While cultural views have begun to accept sexting an increasingly normative sexual behavior, this project might be better accepted when that transition is further along. Factors impacting recruitment, directions for future research, and potential clinical implications are discussed along with potential modifications for the study as recruitment continues with the aim of performing fully powered analyses to examine the efficacy of the intervention.Ph.D., Psychology -- Drexel University, 201
Exploring Supportive Educational Experiences of Transgender and Gender-Nonconforming Students from an Adult Perspective: A Reflective Phenomenology
No full textThe years 2015 and 2016 began an era in which the transgender and gender-nonconforming community received growing attention from outspoken celebrities and government officials. Around the same time, public schools began implementing policies to protect transgender and gender-nonconforming youth while mandating guidelines for inclusion and minimizing stigmas. For many, the transgender and gender-nonconforming community is a commonly misunderstood and sensitive topic, particularly in K-12 public institutions. Given that the past few years were a historical period of change for the transgender and gender-nonconforming community, is it imperative that public school districts hear the voices of these students and address their needs accordingly. The purpose of this phenomenological study was to explore and understand the essence of supportive experiences as transgender and gender-nonconforming adults reflect on their K-12 public educations. This research study was completed by analyzing common themes among the perspectives of supportive experiences. The purpose was to enable educational communities to be better equipped to support transgender and gender-nonconforming students, and to apply social justice to the constructs of K-12 education.Ed.D., Education -- Drexel University, 201
A Phenomenology: Exploring African American Men's Characterizations of Their K-12 Teaching and Learning Experiences in a Large Urban School District
No full textThe purpose of this qualitative study was to explore the urban public school learning experiences of African American men as they recall them and to advance situational pedagogies that are effective at meeting the needs of African American male students. The researcher also drew upon the teacher preparation experiences of current urban public school teachers to determine the extent to which they felt their teacher preparation programs prepared them to address the pedagogical, social, and emotional needs of African American male students. The primary research question of this phenomenological study was, how do African American men who attended a large urban public school system on the east coast characterize their learning experiences? To further guide the research, the researcher posed the following questions: 1. How do African American men characterize their experience as male urban public school students? 2. What do African American men identify as the most critical qualities of urban teachers? 3. How do urban teachers describe their preparation for teaching and learning practices with African American male students? To explore these experiences, the researcher employed a qualitative phenomenological approach to inquiry. The researcher also employed a pragmatic interpretive framework, one focused on praxis; the application of what became known through data collection and interpretive analysis. Four African American men and six teachers of African American male students agreed to either a one-on-one semi-structured interview or to a focus group discussion. Through the interview process, the researcher gathered data rich enough to provide thick descriptions of the K-12 learning experiences of African American men and the teacher preparation experiences of current teachers of African American male students as they recalled them. Once the data were collected and analyzed, the researcher presented findings, results, conclusions, and recommendations.Ed.D., Educational Leadership and Management -- Drexel University, 201