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A Qualitative Case Study on the Perceived Impact that Changing Requirements from Medical Boards are Having on the Day-to-Day Activities of Community Physicians
No full textIn today's healthcare field, recent changes in professional standards, specifically board certification, are affecting physicians who have been practicing medicine for years. While historically board certification was voluntary, in recent years there has been a push to make it mandatory to retain hospital and insurance privileges. In an attempt to make continuous board certification easier to uphold, the American Board of Medical Specialties launched a Maintenance of Board Certification (MOC) program to help physicians keep up to date on their skills and allow easier recertification. This has resulted in intense pushback from members of the medical community who believe in continuing education, but are opposed to the MOC process. The aim of this study is to determine how community physicians perceive these changes on their professional lives and personal well-being. To this end, the research questions were as follows: What are the perceived impacts from recent changes on continuing education requirements for board renewal, on the professional activities of physicians?;What are physicians doing differently within their practice to comply with the new requirements?; With physician stress and suicides featuring predominantly in the news lately, what kinds of impact have the changing requirement over the past three years had on physicians' well-being and retention?; and How do local trends compare with trends being reported at the state and national level? The research questions were answered through a qualitative case study design using an original online survey to participants and then interviewing volunteers to share their experiences. This data was then triangulated to show that participants' perceptions were split almost evenly down the middle. While the dataset was small, it did show that women were less likely to report any negative perceptions or make any changes within their daily practice. Results also showed that physicians in practice over 30 years reported feeling more of an impact on their professional lives than their personal lives and that any negative impact was felt more strongly among outpatient focused physicians. On this basis, it is recommended that physicians work closer with the American Board of Medical Specialties to help improve the process and create a cohesive alignment within the medical profession to reduce any perceived impact. Longitudinal studies could be undertaken using the same questionnaires and research questions to study these changes in other hospitals, locations or populations every few years to identify the direction of the initiative.Ed.D., Educational Leadership and Management -- Drexel University, 201
Development of Computational Fluid Dynamics based Artificial Neural Network Metamodels for Wastewater Disinfection
No full textThe mechanisms of the mixing of two streams are investigated numerically. The transport processes of both mass and heat transfer in the mixing of either two gases or two miscible liquids are studied with 3-D time-dependent computational fluid dynamics (CFD) simulations. The flow fields are calculated for the T-junction (of two circular cross-section pipes that meet orthogonally at a junction) which is one of the most common mixing devices in the study of mass and heat transfer. For turbulent flow regimes, the large eddy simulation (LES) technique is employed. Second-order differencing scheme is applied in the simulation to minimize numerical diffusion. The results obtained by the numerical simulations are verified with available experimental data in the literature for air-methane mixing in a T-junction. In the wastewater disinfection process, Peracetic acid (PAA) is an effective anti-microbial agent for disinfection and has a significant applicability in wastewater treatment processes. Similar to other chemical disinfection technologies, such as chlorination, and ozonation, the performance of PAA is determined by hydraulics of a disinfection contactor, chemical kinetics of microbial inactivation, and specific water characteristics. On-site physical modelling on pilot scale has been an important and usual method to validate the kinetics and the performance for a particular system. However, physical modelling is expensive and time consuming. CFD technique offers an alternative to physical modelling. With increasing computational power on personal computers (PCs), applying CFD simulation on a full-scale reactor is becoming more and more achievable. With proven accuracy on predicting the performance of full scale facilities, CFD is now playing a significant role in the wastewater treatment industry. A transient CFD simulation of a full-scale contactor with reasonable accuracy can be achieved within hours on PCs, which significantly lower the cost of undertaking physical modelling experiments. Metamodels based on artificial neural network (ANN) are computationally efficient mathematical approximations to a highly complex system with multiple non-linear features. With a parametric study of CFD simulations providing training dataset, the metamodel is able to be calibrated to predict the performance of a variety contactors with different geometries, inlet conditions and chemical kinetics. In this thesis, the results of microorganism inactivation and PAA decay in full scale contactors using three-dimensional CFD models are presented. Then the results of the simulations were applied to develop ANN-based metamodels. The performance of metamodels were validated with both CFD simulations and pilot scale experiments.Ph.D., Mechanical Engineering and Mechanics -- Drexel University, 201
How feedback from an emotional game agent affects the player's perceived competence, autonomy, and intrinsic motivation
No full textEmotional game agents (EGA) present a way to provide real-time verbal feedback to the player in an interesting and engaging way. Recent studies have looked at how various types of feedback and game design elements impact player motivation because of its useful application in serious, educational, and commercial games, but none have examined feedback delivered by EGAs. In this project, we look at self-determination theory, a theory of human motivation, and how it has been used in previous game studies. We then present a game review of existing EGAs, classifying the emotions they embody and the ways they are used. The emotions of happiness (joy) and anger were found to capture the affective expressions that are most commonly expressed through existing EGAs. Then a prototype was created, based around the concept of spatial reasoning, in order to provide information about the effect different EGAs have on player motivation, and which players tend to prefer. Our results conclude that happy EGAs have a largely positive impact on variables dealing with intrinsic motivation versus angry EGAs. However, some players find happy EGAs to be boring and angry EGAs to be interesting and engaging. When dealing with EGAs, it became clear that players want to know the driving force behind the emotions agents are expressing.M.S., Digital Media -- Drexel University, 201
An investigation into the factors affecting street tree rainfall interception
No full textAs cities expand to meet the requirements of the growing population, construction of impervious infrastructure causes stormwater runoff during rainfall events. This runoff may contain toxic contaminants and pathogens are is hazardous to people and the environment. Rainfall interception, the process of precipitation retention on tree surfaces that is subsequently evaporated back into the atmosphere, has gained attention for the implications trees may have on stormwater runoff mitigation in urban environments. Although interception has been documented on forest-stands dating to the early twentieth-century, assuming similarities between forest-stands and urban trees is likely inappropriate due to inherent differences in tree physiology and micro-meteorological conditions. Therefore, this dissertation addresses the current literature gap by investigating some of the variables that affect urban tree rainfall interception. The research objectives are separated into three studies: Study 1 (i.e., Chapter 2) evaluates the association between sub-millimeter surface morphology and interception storage capacity of the honeylocust street tree surfaces (Gleditsia triacanthos L.); Study 2 (i.e., Chapter 3) quantifies rainfall interception of the honeylocust in relation to the four canopy phenophases; and, Study 3 (i.e., Chapter 4) examines the interspecific differences of storage capacities and interception depth among ten common street tree species in New York City (NYC). In Study 1, the association between sub-millimeter surface morphology and interception storage capacity of the honeylocust foliar and bark surfaces were evaluated through the integration of bioimaging microscopy techniques, three-dimensional (3D) surface mapping, and laboratory-based interception storage capacities. Results demonstrated a relationship between microrelief and storage capacity among the three canopy phenophases and tree height for the foliar and bark surfaces, respectively. 3D surface mapping revealed insight that greater surface microrelief may facilitate retention by trapping water in reservoirs formed from microstructures (i.e., trichome projections, vein contours, and valley depressions). The dominance of the bark surface was also observed, which consistently had five to six times greater roughness and storage capacity than the foliar surface. Implications from this study raises the question as to the significance of bark and foliar surfaces on the seasonal variation of rainfall interception among the canopy phenophases. The influence of canopy phenophase (i.e., leafless, emergent, full leaf, senescent) on rainfall interception were quantified through field-based monitoring of forty-one rainfall events for three honeylocust street trees in Study 2. While interception percent (i.e., 25.7 - 38.8 %) and depth (i.e., 3.3 - 3.4 mm) varied, ANOVA determined that interception did not statistically differ among the phenophases. Rather, a stepwise regression analysis indicated that interception was most significantly predicted by event-based cumulative precipitation. The limited role of canopy phenophase also may be attributed to the underscoring dominance of the bark surface, which estimated between six and five times greater storage capacity and surface area than the foliar surface, respectively. Irrespective of foliage presence or absence, findings suggest that street trees can effectively intercept rainfall year-round in urban environments, and bark surface characteristics may dictate interspecific interception among street tree species. Study 3 examined the interspecific differences in the bark and foliar storage capacities and up-scaled interception storage depths among ten common species of street trees in NYC. Results showed that bark and foliar storage capacity substantially varied among the species, although mean bark storage capacity was an order of magnitude greater than the foliage. Up-scaled interception storage depth ranged between 1.0 - 4.0 mm among the species, demonstrating that thick-bark species generally facilitated greater water retention than thin-bark species. Specifically, the bark represented > 90 % of the entire interception depth yet contributed 42 % of the surface area. In addition to suggesting that street trees can retain considerable quantities of rainfall, this study emphasizes the critical role bark surfaces have on interspecific interception storage depth and the potential importance of species selection in cities to improve stormwater runoff management.Ph.D., Environmental Engineering -- Drexel University, 201
Factors that Influence Middle School General Education Teachers' Attitudes Toward the Inclusion of IDEA-Eligible Students Who Exhibit Disruptive Behaviors
No full textThis phenomenological study explored the factors that affect the willingness of general education middle school teachers to include IDEA-eligible students who exhibit disruptive behaviors. Despite the legal mandate, The Education of All Handicapped Children Act of 1975 (EHA), requiring students with disabilities to be educated with their nondisabled peers to the maximum extent appropriate, many general education teachers are reluctant to accept these students into their classrooms. Research suggests that this phenomenon has been present in the education system for these last 40 years, and it is more prevalent with students exhibiting disruptive behaviors. Relatedly, inclusive practices have been explored, implemented, and analyzed; and while progress has been made, students exhibiting disruptive behaviors are included less frequently than their peers. Through consideration of participants' individual lived experiences and an array of perspectives about the phenomenon, an improved understanding of this phenomenon surfaced. This study triangulated data from semi-structured interviews, focus groups, and a researcher's journal to identify eight factors that influence middle school general educators' attitudes toward the inclusion of IDEA-eligible students who exhibit disruptive behaviors.Ed.D., Special Education -- Drexel University, 201
Data Reduction Techniques for Efficient Performance Monitoring of Computing Systems
No full textVigilance and maintenance are crucial elements toward the continued performance of any computing system. In datacenters, decisions such as resource allocation and fault detection are often made in direct response to information collected in real-time. A properly monitored system requires managing a massive flow of data, ultimately adding considerable stress to the acts of collection, transmission, analysis and storage. At the server, the act of monitoring poses the problem of resource competition with the application itself. For the transmission of data from servers to central monitoring station, bandwidth limitations become an issue. And at the monitoring station, the availability of memory for the storage of data can prove problematic. This thesis develops a set of frameworks aimed at computationally efficient reduction of data for ease of transmission, potential reconstruction and subsequent analysis of transferred information. The thesis focuses on a setting in which performance data is collected locally at a server and transferred to a monitoring station for analysis. Methods such as Shannon entropy, dual prediction and compressive sampling are utilized to reduce data at the server; we employ Principle component analysis (PCA) at the monitoring station to detect potential anomalies. Entropy is the scalar measure of a distribution's spread, how dispersed or collected the individual points of data are with respect to each other. Dual prediction is a two-part technique designed to break a signal down into a minimal form, the error computed when comparing prediction to signal, at the first stage and restore the signal from this form to its original state, by adding the error back to the prediction, at the second stage. This is accomplished through the use of mirrored prediction units stationed at each stage. Compressive sampling is a technique by which a signal is expressed into a different basis, such as Haar wavelet. Under a proper basis with respect to the signal, it may yield a concise representation of the data or, in other words, effectively become sparse. PCA is a dimensional reduction technique which maps n-dimensional data to a set of orthogonal components known as principal components. From the most to the least principal, these components measure the dimension of highest to lowest variance. Removal of the least principal component(s) will reduce the dimensionality of the data-set with minimized loss of relevant information. We validate these frameworks via experimentation with data collected through two scenarios. In the first scenario, we generate fault-influenced data using long-running enterprise benchmark applications, Trade6 and RuBBoS. In the second scenario, we utilize workload traces collected from one of Google's production clusters. Regarding transmission, experiments show that while transferring only 10% of the original signal, we are capable of restoring the signal with a maintained fidelity between 90%-95%. For PCA-based detection, our tests reveal that we can achieve detection on the level of analyzing the raw data without the cost of restoring a compressively sampled signal with a compression rate exceeding 75%.Ph.D., Electrical Engineering -- Drexel University, 201
Improving Deformable Multi-Grid B-spline Registration using Heuristics and Deep Learning
No full textThe purpose of deformable image registration is to recover acceptable spatial transformations that align two images acquired at different periods of time into the same coordinate system. Due to the growing importance of modern image-guided therapies, the techniques continue to be widely investigated. B-spline based models are commonly used in modeling this type of transformations because of the robustness of modeling continuous dense deformations. However, shortcomings exist in state-of-art B-spline based models, such as the incapability of modeling discontinuous motions and the difficulty in clinical application due to requiring the estimation of an intractable number of free parameters. This thesis develops adaptive B-spline registration models for 3D image volumes and investigates the application of machine learning techniques to improve the accuracy and efficiency in several aspects. The specific contributions are: Reduce the computational burden in parameter optimization for both single grid and pyramid B-spline models, which makes it possible for registration of large-scale 3D image volumes. On one hand, the reduction is accomplished by introducing a parallel framework that partitions each image volume into independent tiles and rapidly solves an analytic formulation of the B-spline algorithm. On the other hand, the degree of freedom is dynamically defined by inspecting local regional features and thus dramatically reduces the number of parameters to optimize. Automatically learn B-spline parameter configuration that best suitable for expressing the deformation underlying registration. The use of multiple grids of varying spatial resolution has been thoroughly investigated due to the sensitivity of the optimization process to local minima while attempting to accurately recover complex local deformations. An octree structured B-spline pyramid construction pipeline, as well as a convolutional neural networks (CNN) based sparsity learning technique, are proposed to infer B-spline grids prior optimization to accurately model anatomical deformations. An approach that improves and evaluates registration quality with fully automatic landmark detection and matching on lung CT images. The respiratory deformation between images acquired from different phases is learned using CNNs to interpolate the correspondence of candidate landmarks on images. The final set of landmarks are integrated into registration to algorithmically improve the registration quality by providing higher-level knowledge of the anatomical form of the images.Ph.D., Electrical Engineering -- Drexel University, 201
Exploring the Lived Experiences and Perceptions of Millennial Nursing Students: Effective Use and Value of Technology on their Educational Achievement
No full textThe faculty at one suburban university on Long Island observed that the majority of nursing students are of the millennial generation who use electronic devices consistently and competently in their daily lives, but did not seem to incorporate technology in their learning. Students seemed to express disinterest, dissatisfaction, and frustration with computer-assisted assignment in nursing courses. As these students did not seem to fit the theoretical description of "digital natives" who have used technology in all aspects of their lives, the researcher felt that further exploration of this phenomenon was logical and timely in order to better develop and implement educational activities consistent with students' needs and preferences. This phenomenological qualitative research study then explored millennial nursing students' use of technology in their learning and how they perceive that learning technologies do or do not contribute to meeting their educational goals. Through in-person classroom observations, an open-ended questionnaire, and individual interviews with baccalaureate nursing students at one university on suburban Long Island, the researcher gained insights into these students' technology preferences. The study revealed that although all students own laptops or tablets and cellphones, the majority are digital fledglings when using technology for learning, having only recently begun to use technology in their studies. Although students verbalized a preference for traditional lecture pedagogy in the classroom, they appeared disengaged and bored in this environment. They expressed that more engaging learning exercises, such as simulation and audience response systems, are more advantageous in contributing to their academic success. They prefer any learning activity regardless of the use of technology that provides structure and scaffolding to learning, is time-efficient but impactful, and is authentic to nursing practice. From this study, the researcher does not imply that technology is the answer to all learning or that students simply want to be entertained in the classroom. Instead, the researcher suggests that nursing faculty working with these students must be pioneering leaders who are well-trained in a blend of traditional and active learning pedagogies to be able to meet the needs of the heterogeneous nursing student.Ed.D., Educational Leadership and Management -- Drexel University, 201
Anion Adsorption and clay-like swelling of Ti3C2Tz MXene multilayers
No full textMXenes are a relatively new and large family of two-dimensional (2D) early transition metal carbides derived typically by etching the MAX phases in fluoride containing solutions. While numerous studies have investigated the role of cations on the interlayer distance (dc/2) between MXene multilayers (MLs) very little is known about the role of anions. Herein, using mainly X-ray diffraction (XRD), the effect of anions on dc/2 of Ti3C2Tz MLs, where T represents various terminations, was systematically studied. The MLs were produced by etching Ti3AlC2 powders in hydrofluoric (HF) acid alone or in mixtures of HF and mineral acids with anions larger than F, viz. hydrochloric, hydrobromic, hydroiodic, sulfuric or phosphoric acids. The nature of the cations present in the post-etching washing solutions was also varied. The results show that the presence of the larger anions demonstrably facilitates water intercalation and de-intercalation. The fact that, for the most part, dc/2 in fully dried MLs are not a function of mineral acid, together with post-etching chemical analysis with energy dispersive spectroscopy (EDS) and X-ray photoelectron spectroscopy (XPS) showing that the amount of residual anions after etching was quite small - in some cases vanishingly so - leads to the conclusion that the larger anions do not enter the interlayer space, but most probably preferentially adsorb onto the positively charged ML edges, keeping the interlayer space open which, in turn, eases water intercalation and de-intercalation.M.S., Materials Science and Engineering -- Drexel University, 201
Community Based Masters Project: A TOCFWH Intervention at Overbrook High School
No full textTo Our Children’s Future With Health (TOCFWH) Inc. is a community based non-profit organization, founded in 1992, with the mission of empowering Philadelphia’s youth, adults, and communities towards healthier living by providing them with community health education as well as services. TOCFWH was founded by Dr. Robin Foster-Drain a New York native who decided to dedicate her life work towards disease prevention and securing good health for inner city children and their families. Other members of the TOCFWH team include Charmaine Sudler-Milligan, Director of Grants Management and Community, Pilar Fernandez-Blakey who helps to coordinate the non-profit’s logistics and activities, as well as Omar Rice, the Youth Coordinator at TOCFWH. TOCFWH Inc. works with a number of partners and predominantly works with residents in the North and West Philadelphia area providing community support. The organization runs a number of youth development programs that provide youth and their families with services as well as an opportunity to build leadership skills and to empower them to become agents of change of their own community. These programs include: Safe Haven, which provides homework assistance, and academic enrichment activities with a strong focus on STEAM (science, technology, engineering, art and math) and literacy, in addition to a number of recreational activities, a workforce development program at Overbrook High School, and Club Den, a year-round youth development program that provides academic support for students in K-8 grade. Additional programs include: a child and adult care food program, a parent empowerment program, and a prevention assistance fund were TOCFWH helps families to identify resources day to day necessities for families.M.P.H., Community Health and Prevention -- Drexel University, 201