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How Creative Placemaking is Impacting Camden,NJ
No full text"City Invincible" is what Walt Whitman, a Camden resident, called this town in his poem "I Dream'd in a Dream" in the 19th century. These words of inspiration are not what Camden residents of this day and age hear on a regular basis about their city. They usually hear phrases along the lines of Camden, one of the "most dangerous cities in America" and Camden, "the stepsister to Philadelphia". This city is still a "City Invincible". They have weathered many storms and have pushed through tough times. The arts, through creative placemaking can help clean up Camden's soiled reputation. My research explores how creative placemaking is impacting Camden, NJ for the better. Creative Placemaking is when the strategic use of the arts, culture, and creativity, by distinctive partners, sparks change in economic development, encourages social change and improves the physical environment of a particular place. How creative placemaking is impacting the city of Camden is important because it provides insight on how effective this tool is and provides more data on how the arts are helping to revitalize small urban communities like Camden, NJ. This city is known to be one of the poorest and dangerous cities in the nation and I believe the arts, with the tool of creative placemaking, are showing that the people of Camden have more to offer than how the nation views them. I used quantitative and qualitative methods to collect data regarding the creative placemaking efforts in Camden. I also conducted surveys and interviews in order to learn about Camden's residents and the arts and cultural organizations. I discovered that Camden residents want positive things to do; most people are financially struggling so they need events that are low cost or free; they need activities to do in their immediate neighborhood; and they would prefer more permanent art initiatives and not the pop up projects that are there one day and gone the next. More permanent projects will add to the long-term revitalization that Camden desires and needs. They also want a reliable arts center that is engaged with them to visit on a regular basis. Since 2014 there have been art galleries, art festivals, public art installations, workshops, farmers markets, art classes, concerts, and outdoor dance fitness classes due to the citywide creative placemaking efforts. There is so much potential in Camden they just needed an opportunity to show it. The creative placemaking efforts that are taking place are providing that platform but needs to be expanded to better serve Camden residents. This research fits into the field of creative placemaking because it shows how effective the strategy is in urban communities. The understanding of how creative placemaking is impacting Camden will provide an example that may be followed by other cities as well. It also shows where Camden is regarding the arts and how they are moving toward having their own arts scene in a few years (Riordan 2016). There are art organizations that are working hard to make the city a more vibrant and creative place that is thriving. To name a few organizations that have been consistent in helping the change become a reality are Camden Fireworks, Connect the Lots, and Rutgers Camden. Walt Whitman's poem inspired the city of Camden to do an art installation with one of its phrases in 2015. Fourteen different artists who were chosen through an open call, painted "City Invincible". In 2016 the letters were used as seating for a picnic area in Camden Night Gardens' Intergalactic Block Party. With help from the community, it was permanently erected on a wall alongside Admiral Wilson Boulevard in 14 twelve-foot letters in 2017. This street is a major gateway to Philadelphia and now it is an artistic gateway where more and more creative endeavors will travel. This is one of few public art displays in the city. This phrase echoes through history and penetrates the desolate places of Camden. When residents see this public art it reminds them that there was a time when the city was vibrant, bustling, and full of life. "City Invincible" gives them hope that it can be that way again.M.S., Arts Administration -- Drexel University, 201
Predicting the Restoration of Incompetent to Stand Trial Criminal Defendants in Jail
No full textState legal systems face a growing challenge: providing effective and timely competency restoration services to pretrial detainees adjudicated IST. The backlog of incompetent defendants waiting in county jails for restoration services and the high costs of assessing and treating incompetence highlights the need for restoration treatment procedures that better identify and triage defendants to different treatment settings commensurate with their treatment needs. Individuals suffering from psychosis make up the majority of IST defendants. Consequently, psychotropic medication is the most common form of treatment for restoring a defendant’s competence. This study investigated the role of psychotropic medication administered in the jail in restoring competency for IST defendants with elevated symptoms of psychoticism and/or paranoid ideation. It also addressed specialized versus general population housing within the jail. Results support the hypothesis that psychotropic medication is an important correlate of adjudicative incompetence and that a subset of defendants may not require a secure bed at a state hospital for restoration services. These findings suggest exploring novel approaches to competency restoration, like jail-based competency restoration, that provide critical services at reduced costs, while maintaining efficacy and quality of care.M.S., Psychology -- Drexel University, 201
Molecular Simulations of 12-Hydroxystearic Acid and Its Derivatives in Organic Solvent
No full text12-Hydroxystearic acid (12HSA) and its derivatives are well-known organogelators, and they play critical roles in a variety of applications. Under gelating conditions, 12HSA forms a three-dimensional network of fibers with lateral fibril dimensions on the submicron scale. It is hypothesized that layers of 12HSA molecules stack to produce a multilamellar structure with alignment of 12-hydroxyl groups that form a chain of hydrogen bonds, and the twist of the fibers is due to the nonlinearity in the carbon chain at the 12th carbon. Furthermore, the sense of twist is sensitive to both the size of the carboxylate counterion and the chirality at the 12th carbon. However, the details underlying these differences are difficult to infer from low-resolution information available from, for example, X-ray scattering. In this thesis, we detail the use of molecular dynamics (MD) simulations to identify key functional group interactions that impact the morphology of aggregates of 12HSA and its derivatives, and to assess the importance of optical purity at the 12th carbon and form of the head-group on aggregate structure. First, in order to assess the aggregate morphology, we conducted MD simulations on microsecond-long time scales for (R)-12HSA at 12.5 wt % in explicit hexane solvent. Self-assembly was accelerated by using a modified force field to prohibit alkane chain dihedral gauche states and then verified by continuation using standard force-field parameters. In three independent simulations, acceleration using a ``gauche-less'' force field resulted in self-assembled ordered aggregates through formation of polarized five- and six-membered rings between inter-12-hydroxyl groups and head-to-head carboxylic acid dimerization. When subjected to the unmodified dihedral force field, two of the three structures remained stable after 1 microsecond of MD. Stable structures exhibited a ``ring-of-rings'' motif, composed of two six-membered acetic acid-dimerized ring bundles with six satellite rings, while unstable structures did not. These structures displayed scattering peaks that agreed with experiment, which suggests this ``ring-of-rings'' structure could be a primary feature of (R)-12HSA in organic solvents. Next, we studied the effect of optical purity on the aggregate structures of 12HSA. We conducted microsecond long MD simulations on (1) (R)-12HSA, (2) (S)-12HSA, and (3) a 50/50 racemic mixture, each solvated at 12.5 wt % in explicit hexane. The ``full-cycling'' method described previously was used for these simulations. Similarly to the optically pure (R)-12HSA aggregates, (R)-12HSA aggregates observed the same ring-of-rings motif. However, the chirality at the 12th carbon dictates the overall twist of the rings and thereby the handedness of the rings. Racemic mixtures did not produce stable ordered aggregates, likely due to insufficient enantiomerically pure ring formation. Next, we analyze the impact of the head-group counterion on aggregate morphology by testing systems of optically pure 12-hydroxystearate with both lithium-carboxylate and sodium-carboxylate head-groups. Due to difficulties with the TraPPE-UA force-field in observing correct ion-carboxylate dimer complexes predicted by quantum mechanical results that showed the high stability of dimer complexes compared to undimerized states, we created predefined dimer complexes based on structures from quantum mechanical calculations. The lithium-carboxylate system exhibited two stable dimer forms: (1) centrally symmetric and (2) diagonally symmetric, while the sodium-carboxylate system only had a diagonally symmetric dimer. We found that similar to the acid systems, all of the ion 12-hydroxystearate systems had inter-hydroxyl hydrogen bonds that were oriented in a ringlike fashion. However, we found that the centrally symmetric dimer allowed for a higher frequency of inter-hydroxyl hydrogen bonds than that of the diagonally symmetric systems, due to its ability for the head groups to pack more easily. Finally, we attempted to find the self-assembly mechanism of 12HSA and its derivatives. We opted to use umbrella sampling with a 1D collective variable (CV) that would influence the alkane dihedral configuration. Multiple CVs were studies, but the most practical CV developed was an indirect control of the alkane dihedral conformation by controlling the distance between carbons 1 and 12. This method had difficulty predicting a free-energy minimum due to time scale constraints. Further enhanced sampling methods should be tried, such as replica-exchange MD (REMD).Ph.D., Chemical Engineering -- Drexel University, 201
Investigating the Influence of Precipitation Patterns and Soil Composition on Soil Moisture Retention in Physical Models of Green Stormwater Infrastructure
No full textGreen Stormwater Infrastructure (GSI) is a rapidly evolving means of managing the excess precipitation generated on impervious surfaces. Though GSI is still in the early stages of development and implementation, this study seeks to optimize performance during precipitation events using scaled-down, GSI prototypes located outdoors. Two types of loamy sand, Standard Stormwater Soil (SSS) and High Sand Blend Stormwater Soil (HSS), were placed atop gravel in rain barrels (hydraulic loading ratio 1:1) to model GSI construction. Barrels were placed on platform scales to record mass, while two soil moisture sensors were placed inside the barrels (the first at 6cm depth and the second at 20cm depth) to take measurements once per minute over a span of 40 precipitation events (March to August). A weather station was also on site to collect precipitation and temperature data once per minute over the same span of events. Through manipulation of this continuous data, discrete values were calculated to describe the data in terms of precipitation characteristics, soil moisture, infiltration, mass changes, and moisture retention. Correlation charts and full model stepwise regression equations were then used to relate the dependent variables of change in soil moisture and change in mass to other precipitation, temperature, and soil moisture variables. These data show that antecedent moisture conditions, the deeper soil moisture sensors, and the total amount of precipitation are indicative of the overall soil moisture changes during and after an event. Specific to the HSS, precipitation travels through the GSI quickly, in comparison to SSS which retains more moisture for a slower release of precipitation over time. Overall, both bare soils are useful for use in this particular model of GSI and should be tested in more extreme conditions, with larger hydraulic loading ratios, and using outflow measurement devices as well.M.S., Civil Engineering -- Drexel University, 201
Preparing Special Education Teachers to Work with Low-Incidence Populations - The Teachers' Perspectives: A Phenomenological Study
No full textA critical issue in the preparation of special education teachers working with students with significant disabilities is the lack of commonality in what preparation programs should include in their academic plans of study. As such, some special education teachers enter the workforce unprepared for the expectations of their role responsibilities. This level of unpreparedness is further intensified when teachers do not receive adequate support during their early years in teaching. Special education teachers of students with significant disabilities require additional support as they seek to balance the academic and functional needs of their students. This phenomenological study explored the lived experiences of early-career special education teachers of students with significant disabilities and identified the skills and administrative support the teachers needed to provide high-quality instruction to their students.Ed.D., Educational Leadership and Management -- Drexel University, 201
Linking behavioral diversity with genetic and ecological variation in the Nigeria-Cameroon (Pan troglodytes ellioti)
No full textTropical rainforests are rich in vertebrates, the result of processes that generate and maintain biological diversity, and low extinction rates under relatively stable climatic conditions. The Gulf of Guinea in Central/West Africa is a biodiversity hotspot with several endemic species, including several primate species. The diversity of endemic species found in this region has been attributed to a complex forest history during the Pleistocene; habitat variation associated with the confluence of the Gulf of Guinea rainforest to the west with the Congo Basin rainforest to the south and drier savanna habitats to the north; and biogeographic barriers including the Cameroon Highlands and riverine barriers, such as the Sanaga River in Central Cameroon. The contributions of the Sanaga River and Cameroon Highlands in promoting species diversification have been examined in some detail, and a growing body of data, suggests that environmental variation, particularly in an ecotone area in southern Cameroon has been important in promoting the diversification of birds, lizards and insects. Little is known about whether ecological variation has contributed to the diversification of endemic mammals across this region. The chimpanzees of Cameroon present a unique opportunity to investigate how ecological variation contributes to promoting intraspecific divergence in the endemic mammals of the region. In addition to harboring two chimpanzee subspecies (Pan troglodytes troglodytes and P. t. ellioti), there are two distinct gene pools associated with P. t. ellioti. These two gene pools were previously shown to inhabit two significantly different niches - one associated with the mountainous rainforest habitats found in western Cameroon and one associated with the ecotone habitats found in central Cameroon. This thesis explores environmental and ecological differences between rainforest and ecotone habitats at a fine geographic scale, and compares and contrasts chimpanzee socioecology patterns between these habitats. Research was conducted from January 2016 to December 2017 at three study sites to represent a range of environments inhabited by P. t. ellioti. I completed surveys for 15 months (January 2016 to March 2017) at two rainforest sites (Njuma and Bekob) in Ebo forest. Njuma was selected for study because it represents relatively undisturbed lowland rainforest, whereas Bekob represents a regenerating human-modified lowland rainforest landscape. Complementary studies were also completed for 24 months (January 2016 to December 2017) at one ecotone site in Mbam & Djerem National Park (Ganga). Quantitative ecological methods were used to characterize habitats and the seasonal availability of fleshy fruits that are important to chimpanzees. Since chimpanzees across the sites are not habituated to humans, I used indirect methods (fecal samples and nests) to investigate chimpanzee diet and nesting patterns. The first aim of study was to examine whether and how the niches of P. t. ellioti in western Cameroon (Njuma and Bekob) differed from the niche occupied by P. t. ellioti in central Cameroon (Ganga) at fine geographic scale. The main variables that distinguished the rainforest from the ecotone habitats included rainfall (annual amounts are higher at the rainforest) and the diversity, density and size of trees (higher at the rainforest than the ecotone). On the other hand, the ecotone had a higher density of lianas and terrestrial herbaceous vegetation. The availability of fleshy fruits was higher at the ecotone, though with marked seasonality compared to the rainforest. At Bekob, there was the prevalence of introduced and secondary forest plant species that I predicted to be important in the socioecology of chimpanzees. The second aim of the study was to examine how occupying rainforest and ecotone niches impact chimpanzee feeding behavior. The main differences in the dietary ecology of the ecotone and rainforest chimpanzees were in the seasonal variation of fleshy fruits and fibrous foods in their diets. Fleshy fruits were the most important dietary component for rainforest chimpanzees in the dry season, whereas the diet of the ecotone chimpanzees was dominated by fibrous foods. Conversely, in the wet season, the proportion of fleshy fruits was more significant in the diet of the ecotone chimpanzees, while fibrous foods were of more significance for the rainforest chimpanzees. Consistent with other human-modified environments, introduced and secondary forest species including Elaeis guineensis and Musanga cecropioides were important dietary components for chimpanzees at Bekob, especially during periods of low fleshy fruit availability. Animal consumption, including vertebrates and invertebrates was more significant at Ganga, and was inversely associated with fleshy fruit consumption. Finally, the third aim of the study was to examine how occupying rainforest and ecotone niches impact chimpanzee nesting behavior. Fruit phenology was an important factor in nesting site selection at the ecotone while rainforest chimpanzees selected steep slopes, hypothesized as an antipredation strategy. Larger nest groups sizes were linked to periods of higher fruit availability especially at the Ganga. Chimpanzees across the three sites had site specific preferences for nesting tree species, but Strombosia grandifolia was commonly preferred across the sites, while nesting in Elaeis guineensis was exclusive to chimpanzees at Bekob. The dietary and nesting patterns of chimpanzees differed considerably between rainforest and ecotone, and may have implications that will improve understanding about why this region is an important area for the genetic diversification of chimpanzees. The ecotone habitat of Ganga is characterized by marked seasonality in fleshy fruit availability and seasonal dietary shifts at the ecotone could imply wider ranging, larger territories and lower levels of gregariousness among chimpanzees. In contrast, the rainforest habitats of Njuma and Bekob are characterized by less pronounced seasonality in fleshy fruits and seasonal dietary shifts. This could reflect smaller territories and more sociality in the rainforest chimpanzee populations. This differentiation in socioecological patterns may be responsible for observed genetic patterns in chimpanzees across this region.Ph.D., Biological Sciences -- Drexel University, 201
Computational Mechanics of Knitted Textiles
No full textKnitted textiles are hierarchically structured materials. Compared to other materials such as fiber-reinforced composites or metals, knitting provides much finer control over the manufacturing process and creates a variety of multi-scale structures using a range of input materials. Mechanical behavior of knitted textiles is difficult to be efficiently predicted by traditional computational methods due to its complicated, entangled internal structures. Flexural motion, interaction activities and hierarchical structure of or between sub-components contribute to a complex behavior with high nonlinearity and instability of knitted textiles. This dissertation aims to develop an integrated computational framework for knitted textiles. To comprehensively understand the mechanical behavior of knitted textiles, knitted textiles were firstly treated as freestanding structures. Specifically, predictions of mechanical behavior of knitted textiles were first obtained by employing direct numeric simulation (DNS) using 3D Finite Element Analysis (FEA). Given the geometrical details of the entangled yarns included in the 3D models used, the DNS approach is capable of investigating the influence of various design parameters at the yarn level, including loop architecture, material properties, as well as interfacial interactions. However, the most intractable thing for a free-standing structure with such complex internal geometry is that its behavior is dependent on the size of computational domain, namely size effect. The expensive computational cost, on the other hand, hinders the scaling up of DNS. To address this issue, DNS of the mechanical behavior of knitted textiles was for the first time conducted on High Performance Computing (HPC) using the explicit FEA method which was compared to implicit analysis. The results presented demonstrate satisfying accuracy and higher order efficiency with reduced memory requirements of the explicit method which allows for improved efficiency in simulations of larger computational domains, while also demonstrate that HPC could be a valuable resource for computational material design applied to advanced manufacturing. Furthermore, efforts to develop Reduced Order Models (ROM) for knitted textiles based on the available DNS results were also presented which were shown to provide an alternative approach to predict multi-scale behavior in addition to consist a tool that could be leveraged in future micro-structure optimization investigations. Moreover, a first order, two-scale homogenization scheme was modified and applied by considering the knitted textile models as a material point in a far field. The equivalent macro stress and consistent material stiffness are derived from the micro level where specific 3D knitted textile models are used. The macro filed with unknown material properties is eventually linked to the micro level by a user subroutine which can convey the equivalent macro stress and stiffness in a looped form of FE code. The multi-scale homogenization scheme is computationally economic and powerful in predicting the behaviors at both the macro and micro level for knitted textiles.Ph.D., Mechanical Engineering and Mechanics -- Drexel University, 201
Performance analysis of statistical anomaly detection algorithms
No full textStatistical anomaly detection (SAD) is an important component of securing modern networks facing constantly changing threats. This dissertation focuses on solving several existing problems of SAD in network security: i) performing anomaly detection distributedly in a low-cost manner; ii) analyzing the relationship between training sample size and the anomaly detection accuracy; iii) the application of SAD to detect malware on IoT devices; iv) the application and performance analysis of SAD to detect denial-of-service (DoS) attacks in wireless networks. First, we consider SAD where network data is collected and stored in geographically distributed locations. In the distributed scenario, transmitting raw data to a central server causes large communication overheads when the dimension and size of the data are high. Our work considers distributed principal component analysis (PCA) based SAD algorithms which maintain a high level of accuracy in estimating the global principal subspace from several leading local singular values and singular vectors, with a significant reduction in the volume of data exchanged. Next, the relationship between the training sample size and the detection accuracy of PCA-based SAD is addressed. We show that under a Gaussianity assumption, the discrepancy between the true principal subspace and the sample principal subspace can be upper bounded by a function in inverse proportion to the square root of the sample size and the covariance matrix's eigengap. We also present a saddlepoint approximation to the false alarm rate of the PCA-based SAD. SAD algorithms may be used to detect malware on IoT related devices, such as home routers and intelligent virtual assistants. Malware infected devices may behave abnormally and thus produce unusual system call traces. We apply several different SAD algorithms on system-call frequency features to detect malware infection of IoT devices. Finally, We employ PCA and a Markov chain based SAD to detect reactive jamming attacks in wireless networks. In the aspect of detecting the stealthy reactive jamming attacks, we propose two variants of PCA-based SAD algorithms that achieve higher detection accuracy, and a target attribution algorithm that identifies the node under attack. In the aspect of detecting the random reactive jammer (RRJ), we propose a novel reactive jamming detector and a mathematical model for an intelligent RRJ based on a Markov chain modeling of the carrier sense multiple access (CSMA) mechanism of wireless networks.Ph.D., Electrical Engineering -- Drexel University, 201
Linking Complex Nutrient Kinetics and Ecological Processes within a Photosynthetic Mixed Microbial Community
No full textAnthropogenic point and non-point nutrient sources have long been implicated in the eutrophication and disruption of surface waters. The application of algal biotechnologies provides opportunities to remediate municipal, agricultural, and industrial waste streams while enhancing nutrient cycling and producing an economically valuable product in the form of algal biomass. Despite interest in the development of these technologies there exist limitations in understanding the complex behavior of mixed algal-bacterial microbial communities, which may in turn constrain the performance of such systems in an engineered setting. The goal of this dissertation is to identify how nutrient loading in photobioreactors affects the microbial community and its ability to carry out nutrient uptake and produce algal biomass. One of the major barriers in the way of algal-based biotechnology's adoption is the high energy costs associated with dewatering biomass prior to processing. To address this challenge, a novel bioreactor called a high density bioreactor (HDBR) was adapted to a photobioreactor configuration. Over the course of experimentation we demonstrate that HDBRs are able to consistently produce highly dense biomass, while removing the bulk of nutrients and producing high quality effluent with low suspended solids content. Metagenomic analysis was employed to characterize the functional capabilities and taxonomic composition of the microbial communities within the reactors. We found Chlamydomonas reinhardtii and Parachlorella kessleri to be the two dominant algal strains and a member of the Leptolyngbya genus to be the dominant Cyanobacteria species. Nitrifying and denitrifying bacteria composed a small but significant amount of the microbial community; their abundances were quantified using real-time quantitative PCR (qPCR). This information was used to interpret and explain the patterns in nitrification and nitrogen removal carried out by the community as a whole. Further reactor studies were carried out to characterize the impact that N species availability (NH4+ vs NO3-) had on total nitrogen removal, and how organic carbon availability impacted those dynamics. It was determined that, in these systems, NO3- loading was more dominant in determining microbial community structure, that NH4+ had little effect (at least within these experiments), and that having NPOC available significantly increased nitrogen and phosphate removal. It was also demonstrated that observed removal rates can be modeled as a function of the nutrient loading parameters using the constrained variance of the microbial community obtained from redundancy analysis.Ph.D., Environmental Engineering -- Drexel University, 201
Classroom Without Walls Excursions and Their Impact on the Affective Growth of International Middle School Students
No full textEach school year, it is common for international middle schools to offer outdoor experiential education programs that take them off campus for three to seven days. The programs aim to extend learning beyond the school campus into environments that allow for the extension of one or more of the following categories of activities, adventure, leadership, team-building, service learning, and academic. The setting for these excursions is primarily outdoors, in nature, with additional activities in areas or edifices of cultural or historical significance. Although the specific objectives of each school may vary, these trips are invariably viewed as an opportunity for students to develop deeper relationships with their teachers and peers, to promote personal affective growth, and to foster a deeper understanding of the local culture that they are visiting. The term for this type of program at the school in which this study takes place is Classroom Without Walls (CWW). Looking through a social constructivist lens, and based on three literature streams, (a) friendship skills and a sense of belonging, (b) perceived competence and self-efficacy, (c) locus of control and personal responsibility, this non-experimental, pre-test/post-test quantitative study applied the ROPELOC instrument as a pre and post survey tool in order to explore the effects of CWW excursions on perceived personal abilities and sense of personal responsibility of both host national and foreign national participants. Results showed, using responses from 167 middle school students in an international school in Colombia, statistically significant gains in perceived personal abilities as well as statistically significant gains in perceived personal responsibility, while showing no statistically significant changes in ROPELOC scores based on type of student.Ed.D., Education -- Drexel University, 201