etd @ Mason (Electronic Theses and Dissertations)

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An ETD is a dissertation or thesis that is submitted and archived electronically. This collection contains dissertations, theses, and projects from various programs at George Mason University.

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Tidal Freshwater Potomac River Eutrophication: Patterns and Relations to Climate Change, Nutrient Management and In Situ Factors
(2000-05-15) Sklarew, Daniel M.; Sklarew, Daniel M.; Jones, R. Christian
Eutrophication, the transition of an aquatic ecosystem from nutrient-scarce to nutrient enriched conditions, is a water quality concern for rivers and coastal zones globally. The tidal freshwater (TFW) Potomac River, in particular, was strongly impacted by anthropogenic eutrophication throughout the twentieth century. Hydrometeorological and in situ biogeochemical factors may contribute to the persistence of eutrophic conditions in the TFW Potomac River, despite advancing nutrient management initiatives. This study investigated the patterns of TFW Potomac River eutrophication and examined water quality relations to nutrient inputs, climate change, and in situ factors over the 1985-1997 period. Eutrophication indicators included total phosphorus (TP), total nitrogen (TN), and algal biomass as Chlorophyll a (Chl a). Nutrient inputs from the non- tidal river and nearby wastewater treatment plants (WWTPs) were examined separately and in aggregate. Climatic factors, such as solar energy, air temperature, wind, precipitation, and freshwater inflow, were also considered. In situ factors comprised both abiotic (e.g., pH) and biotic (e.g., the Asiatic clam, Corbicula fluminea) variables. Statistical parametric, non-parametric and graphical methods were used to analyze historical data from various federal, state, and local monitoring agencies, both before and after a basin-wide ban on phosphate in laundry detergents. A field study over summer 1997 further clarified effects of partial effluent denitrification at Blue Plains, the region’s largest WWTP. Data analysis examined patterns and relations longitudinally, across various temporal scales (multi-day, seasonal, annual, and inter-annual). Ambient nutrient concentrations were generally an attenuated function of upstream source nutrient concentrations. TP was longitudinally stable, while TN crested near the outfall pipes from the largest WWTPs. Below this area, Chl a increased substantially. Chl a varied directly with 14-day solar energy, 4-day temperature and, in upper segments, wind speed; and inversely to freshwater inflow and, in lower segments, 4-day wind speed. Chl a also increased with TP during warm, dry weather, consistent with pH-related sediment TP release. No clear relation was established between Corbicula and algal biomass, however. Both the phosphate detergent ban and Blue Plains denitrification were found to have limited impact on TFW Potomac eutrophication. Season-specific and year-to-year patterns and relations are also discussed.
Policy Design for Competitive Retail Electric Institutions: Artificial Intelligence Representations for a Common Property Resource Approach
(2001) Pandit, Nitin S.; Pandit, Nitin S.; Haynes, Kingsley E
ABSTRACT
Socio-Cultural Significance of Stuffed Animals in Washington D.C. Metropolitan Area
(2001-05) Needham, Cat L.; Scimecca, Joseph
This thesis describes the significance of stuffed animals as derived from relevant areas of the socio-cultural landscape from three studies conducted in Fairfax, Virginia—one participant observational study, one non-participant-observational study and one qualitative/interview study. The three studies' results are to compare them to those derived from an examination of the "larger" picture (mass media, advertising, etc.) and determine what, if any, similarities and/or differences exist between them. A conclusion follows which summarizes and decisively identifies what significance stuffed animals have within the socio-cultural landscape of the Washington, D.C. Metropolitan area.
New Unit Root Tests to Decrease Spurious Results with Applications in Finance and Temperature Anomalies
(2006) Herranz, Edward; Herranz, Edward; Gentle, Dr. James
Simulation studies show that when testing for cointegration with pairs of independent explosive($\gls{phi1} >1$) AR(1) time series almost invariably lead to spurious cointegrating relationships. A new unit root test, the lagged-series test, is proposed with similar power to the ADF test for non-explosive AR(1) series but higher power in the explosive case. The lagged-series unit root test can be combined with other unit root tests such as the Elliot-Rothenberg-Stock tests and the Zivot-Andrews test, as well as the ADF test to improve the statistical power in the explosive case. A new unit root test, the Hybrid Bai-Perron Zivot-Andrews test, is proposed which allows for structural breaks in intercept and linear trend under the null hypothesis and compares favorably in some cases to the Lee-Stratizich unit root test. A new testing procedure to check for stationary to nonstationary shifts in a time series, referred to as the Hybrid Bai-Perron ADF procedure, is proposed and tested. It is shown that different unit root test related statistics can be combined using deep learning neural networks and results in techniques that outperform individual unit root tests in various simulation studies. Simulation based studies of the ADF, ERS-Ptest, ERS-DFGLS, the Zivot-Andrews, and the new lagged-series unit root tests, under various model configurations were made and compared.
The Effect of Nature of Science Metacognitive Prompts on Science Students' Content and Nature of Science Knowledge, Metacognition, and Self-Regulatory Efficacy
(2007-10-03T18:00:41Z) Peters, Erin; Peters, Erin
The purpose of the present quasi-experimental mixed-method design is to examine the effectiveness of a developmental intervention (4-phase EMPNOS) to teach the nature of science using metacognitive prompts embedded in an inquiry unit. Eighty-eight (Nˆ) eighth grade students from four classrooms were randomly assigned to an experimental and a control group. All participants were asked to respond to a number of tests (content and nature of science knowledge) and surveys (metacognition of the nature of science, metacognitive orientation of the classroom, and self-regulatory efficacy). Participants were also interviewed to find problem solving techniques and shared experiences between the groups. It was hypothesized that the experimental group would outperform the control group in all measures. Partial support for the hypotheses was found. Specifically, results showed significant gains in content knowledge and nature of science knowledge of the experimental group over the control group. Qualitative findings revealed that students in the control group reported valuing authority over evidence, while the experimental group reported that they depended on consensus of their group on the interpretation of the evidence rather than authority, which is more closely aligned to the aspects of the nature of science. Four-phase EMPNOS may have implications as a useful classroom tool in guiding students to check their thinking for alignment to scientific thinking.
Weather-Related Crashes on Public Land
(2007-10-09T19:45:26Z) Moore, Lewis; Moore, Lewis
This research examines weather and road conditions relation to traffic crashes on Bureau of Land Management (BLM) and U.S. Forest Service (FS) land in three states: Idaho, Oregon and California. Crash data for Idaho and Oregon were supplied by the state transportation departments while the California data were obtained from the Federal Highway Administration’s Highway Safety Administration (FHWA) . The results are mixed, probably because of the different methods of data collection: Idaho seems to have particularly severe crashes during bad weather on these public lands when all roads on the public lands are compared with other rural Idaho state and federal highways. Oregon's comparable weather-related crashes do not show such severe crashes in poor weather or road conditions, but Oregon on these federal lands crashes in good weather are very severe as are the “non-weather” crashes on lightly traveled rural highways in the State. California’s FHWA Highway Safety Information System data offered a much more objective test of crashes on the public domain, based on federal and state roadways versus private, rural land roads during "weather" and “non-weather” conditions. In the aggregate, weather-related crash differences appear non-significant for California’s public and private lands. The salient finding in California is that on average, "nonweather" crashes on BLM and USFS land are significantly more severe than on comparable rural roadways in the State. Using FHWA projections of crash costs, the BLM and FS crashes produce about 30 percent greater losses.) The latter finding may be a result of more speed with good weather conditions, adverse roadside environments and the increased time required for emergency response to public land crashes. Future deployments of Intelligent Weather technology for rural California roadways could benefit from the database assembled for this research, especially the weatherrelated crash analysis for roadway/county/federal or rural land contingencies in Appendix A. Dramatic differences in local crash costs were observed in the limited fine-scale analysis done in this study. Providing weather and location crash cost in a Geographical Information System would further assist management and policy-makers in efforts to reduce rural crash risk.
Ultra-Fast High-Temperature Microwave Processing of Silicon Carbide and Gallium Nitride
(2007-10-10T17:45:30Z) Sundaresan, Siddarth; Sundaresan, Siddarth
A novel solid-state microwave annealing technique is developed in this work for post-implantation annealing of SiC and GaN, and for the controlled growth of SiC nanowires. This technique is capable of heating SiC samples to temperatures in excess of 2100 ºC, at ultra-fast temperature ramping rates > 600 ºC/s. Microwave annealing of ion-implantation doped (both p-type and n-type) hexagonal SiC was performed in an uncontrolled (air) ambient, as well as a controlled 100% atmosphere of nitrogen, with or without a protective graphite cap. Microwave annealing was performed in the temperature range of 1500 ºC – 2120 ºC, for durations of 5 s – 60 s. Uncontrolled ambient microwave annealing of SiC at temperatures > 1700 ºC resulted in a significant oxidation of the SiC surface, leading to a loss of the implanted layer. Annealing in a 100% nitrogen atmosphere eliminated the oxidation problem. For microwave annealing at temperatures ≥ 1800 ºC, significant SiC sublimation was observed, even for 15 s annealing. Microwave annealing with a photoresist-converted graphite cap solved this surface sublimation problem for annealing temperatures up to 2100 ºC. For the P+ and Al+-implanted SiC, sheet resistances as low as 14 Ω/ and 1.9 kΩ/ and majority carrier mobilities as high as 100 cm2/Vs and 8.3 cm2/Vs, respectively, were obtained. For the Al+ -implanted SiC, sheet resistances as low as 1.9 kΩ/ and hole mobilties as high as 8.3 cm2/Vs were obtained. These values constitute the best ever reported electrical characteristics for ion-implanted SiC. Microwave annealing at temperatures > 1800 ºC not only removed the implantation-induced lattice damage but also the defects introduced during crystal growth. Microwave annealing of in-situ as well as ion-implantation acceptor doped GaN was performed in the temperature range of 1200 ºC – 1600 ºC, for a duration of 5 s, using different protective caps (AlN, MgO, graphite) for protecting GaN surfaces during annealing. Pulsed-laser deposited AlN was found to protect the GaN surface effectively, for microwave annealing at temperatures as high as 1500 °C. The RMS surface roughness (0.6 nm) of the GaN sample annealed at 1500 °C with an AlN cap is similar to the value (0.3 nm) measured on the as-grown sample with a decrease in the compensating deep donor concentration. Cubic 3C-SiC nanowires were grown by a novel Fe, Ni, Pd, and Pt metal catalystassisted sublimation-sandwich (SS) method. The nanowire growth was performed in a nitrogen atmosphere, in the temperature range of 1650 ºC to 1750 ºC for 40 s durations. The nanowires grow by the vapor-liquid-solid (VLS) mechanism facilitated by metal catalyst islands. The nanowires are 10 μm to 30 μm long with about 52% of them having diameters in the range of 15 nm – 150 nm, whereas 14% of the nanowires had diameters in excess of 300 nm.
Microfluidic Devices for Forensic DNA Analysis
(2007-11-19T16:53:21Z) Shah, Jayna; Shah, Jayna
The development of integrated, miniaturized, and portable DNA analysis systems is crucial to alleviate massive backlog of unanalyzed samples and to address ever increasing demand for these assays. This thesis work contributes towards the development of a fully integrated microdevice capable of "sample in – answer out" for forensic DNA analysis. Specifically, this work describes the development of rapid and robust fabrication protocol for solvent-actuated bonding of polymeric thermoplastic substrates at room temperature, the development of microchannel wall coating strategies to eliminate analyte-wall interactions for high resolution separation of single-stranded DNA, and the characterization of a thin-film planar microwave transmission line for microfluidic heating applications. The solvent-actuated bonding protocol was based on the difference in capillary forces between the microchannel and the interstitial space between the surfaces of the two substrates to be bonded. This force differential wicked the bonding solvent into the gap between the substrates causing them to bond. The technique was implemented by placing the two substrates under moderate pressure, applying a moderate pneumatic vacuum to the fluidic channel, and introducing tens of microliter of bonding solvent through one end of the fluidic channel. The effect of bonding solvent on the dimensions of the microchannel was analyzed, and the mechanical robustness of the bonded devices was also characterized. Electrophoretic separation of single-stranded DNA (ssDNA) was successfully performed to demonstrate the functionality of these devices. To enhance ssDNA separation performance, schemes to modify poly(methyl methacrylate) (PMMA) – the primary substrate used in this work – were explored. This two step process consisted of altering surface hydrophilicity via surface activation using either nitric acid or UV/ozone followed by coating the surfaces with adsorptive polymers. Contact-angle measurements of the pristine and modified PMMA substrates were performed to quantify the change in wettability of the surface. Twofold increase in the separation efficiency was achieved by implementing these surface passivation strategies. Finally, the use of a thin-film planar microwave transmission line as a microwave power source was investigated for on-chip microwave heating of fluids. The microwave characterization data was used to develop a first-order analytic model of the microwave power absorption. The model was used to understand microwave power flow through the device and to calculate the fraction of the incident power absorbed in the fluid. Additionally, a fit of the predicted temperature obtained using this model to the measured temperature was performed to evaluate efficiency of this heating method.
An Analysis of the Potential Direct or Indirect Influence Exerted by an Al Qaeda Social Network Actor on Future Biological Weapon Mission Planning
(2007-11-21T16:57:02Z) Baken, Denise; Baken, Denise
The current conflict known as the “War on Terror” pits several sovereign states (United States and its Allies) against a non-state entity. This entity, al Qaeda, is a global social network with religious doctrine adherence as its declared locus. Terror experts agree that the economic and psychological damage al Qaeda inflicted on 9/11 is miniscule compared to the potential damage by a biological weapon. This dissertation is an analysis of the potential direct or indirect ability of al Qaeda members to select and use a biological weapon.
Low Ionization Nuclear Emission Line Regions: The "Missing Link" in the Active Galactic Nucleus Population
(2007-11-21T17:05:30Z) Dudik, Rachel; Dudik, Rachel
The horizon of the universe, once thought to extend only to the disk of the Milky Way, is now known to embrace a host of diverse galaxies, from active galaxies such as quasars and Seyfert galaxies to normal galaxies such as our own. The recent discovery that virtually all local galaxies harbor massive nuclear black holes, has provided convincing evidence that active galactic nuclei (AGNs) and normal galaxies are indeed connected. The nature of this connection and the evolutionary history connecting them, however, continues to be elusive. Low Ionization Nuclear Emission-line Regions (LINERs) are the dominant population of 'active' galaxies in our local universe and may indeed be the missing piece to the evolutionary puzzle. LINERs are defined by optical line ratios uncharacteristic of photoionization by normal main sequence stars. While classical AGNs represent at most a few percent of the galaxy population, LINERs constitute as much as 50% of the total local extragalactic population. However, despite several decades of intense research, the ionization mechanism responsible for the unusual LINER spectrum remains a mystery. What is the ionization mechanism responsible for the empirical line ratios characteristic of LINER galaxies? How do LINERs fit into the overall evolution of galaxies as we know it? Are LINERs a subclass of AGN? What is the evolutionary connection, if any, between galaxies with heavy starburst activity and AGNs? The majority of LINERs are dust enshrouded and therefore very luminous in the far-infrared. The far-infrared (far-IR) luminosity to the luminosity in the optical Bband (center = 4400A), the so-called IR-brightness ratio, can be used as a gauge of the amount of dust in host galaxy. LINERs span a wide range of LFIR/LB ratios, tending predominantly toward the IR-bright end. However, the majority of research to-date has been based on optically selected samples which are partial toward IR-faint LINERs. This bias toward IR-faint galaxies could have important consequences on statistical analyses which examine the fraction of LINERs hosting AGNs. In order for an accurate picture of LINERs to emerge, IR-bright as well as IR-faint galaxies must be studied. What fraction of IR-bright LINERs are AGNs? In light of the open questions regarding these remarkable objects, the central goal of this dissertation is to carry out a systematic multi-wavelength X-ray imaging and Infrared spectroscopic survey of nearby LINERs spanning a wide range of IRbrightness ratios in order to 1) characterize the dominant energy source responsible for their optical line ratios, 2) compare the AGN detection rate in our infrared selected sample with the optically selected samples, 3) determine the luminosities, spectral characteristics and accretion properties of the AGN-LINERs and compare them with the standard active galaxies, and finally, 4) relate the host galaxies properties to the properties of the central source in an attempt to constrain the role of LINERs in galaxy evolution and formation models.
Actualizing Human Rights Norms in Distanced Spaces; an Analysis of the Campaign to Eliminate Conflict Diamonds and the Capital Market Sanctions (Sudan) Campaigns in the United States
(2007-11-27T18:50:22Z) Muvingi, Ismael; Muvingi, Ismael
In the late 1990s and early 2000s, social justice activists in the United States initiated two coalition based campaigns aimed at ameliorating the violence associated with extractive industries in Angola, Sierra Leone and Sudan. The ideological diversity and the disparate interests of the coalition participants were an intriguing puzzle and part of this dissertation is an exploration of how it is that these widely diverse actors were able to collaborate and successfully run the campaigns despite their significant differences. I advance the argument that diversity of ideological subscription is no bar to coalition work in campaigns because a strategic basis for operationalization enables collaboration across ideological and interest differences. I utilized a tripartite opportunity structure framework to analyze the campaign. Extant scholarship on social movements is predominantly state centric, but in these cases the violators or human rights were other than states i.e. corporations, rebels and warlords that operated across state boundaries and were enabled by the market. To better encapsulate the range of structural opportunities I therefore delineated institutional structures rather than just state structures. The second leg of the framework emanates from the problem of separating framing from opportunity structures. The efforts of the activists through the framing of their messages as well as their mobilizing efforts were met by the counter frames of the targets and mediated by various opportunity structures that comprised the prevailing context. Rather than simply a unidirectional frame activity from the activists, I wanted to capture the competing nature of the framing processes in the public sphere. Thirdly, although the campaigns took place during the same historical time space and were motivated by the same phenomenon of violence in extractive industries, they had divergent trajectories and different outcomes. From the investigations it was fairly clear that the economic and strategic interests within the U.S. context largely determined the campaign outcomes. I therefore utilized a geopolitical opportunity structure to complete the analytical framework.
Evaluation of Intervention Programs Designed to Address High School Racial Conflicts
(2007-12-11T18:50:26Z) St. Jean, Gerardine; St. Jean, Gerardine
This dissertation research examines racial conflict—one of the contributors to school violence—and effective intervention programs. This dissertation study presents research-and theory-based integrated intervention programs (a synthesized program with conflict resolution and multicultural components) as an effective resolution to high school racial conflicts. Some schools in the United States have created a database that lists effective intervention programs for specific school problems, but most of the programs only deal with general violence and violence related to substance abuse—none identify effective approaches to racial conflicts at schools. This dissertation research is a unique first step to look at effective techniques and identify appropriate programs to deal with racial conflicts to these databases. It tests the following hypotheses: 1 Educational intervention programs that encompass assimilated multicultural and conflict resolution training contents (integrated programs) in its integrated lessons are more effective at impacting the reduction of racial incidents at high schools. 2 High schools that do not utilize intervention programs with a combination of multicultural and conflict resolution training contents but only rely on strict policies and practices (e.g., laws and rigid discipline) are most effective at reducing the number of racial incidents in high schools. Lastly, the dissertation study describes the development of a model that schools can use to assess their needs and determine steps to implement a suitable intervention program. This research project is a summative evaluation study that uses multiple methods (survey, experiment, and case study) and encompasses a selection of high schools in Pennsylvania that meet the criteria of the study. Principals, teachers, and parents from selected schools are the key participants in the study.
Multi-Objective Optimization of Blast Simulation Using Surrogate Model
(2007-12-12T16:14:50Z) Tsuga, Toshihiro; Tsuga, Toshihiro
A multi objective optimization approach using a Kriging model coupled with a Multi Objective Genetic Algorithm (MOGA) is applied to a blast damage maximization problem composed of two objectives, namely number of casualties and damage to buildings. The predicted Pareto front is located using a MOGA on the Kriging model. The location with maximum uncertainty along the Pareto front is added to the list of sample points. After each sampling, the Kriging model is reconstructed and this process is repeated until the maximum uncertainty is reduced. The cases run show that the Pareto front is not always intuitively discernable. `Best locations’ can vary significantly depending on the weight given to each optimization objective. The results also indicate that the effect of the additional cost incurred by the procedure to construct the `model of the model’ totally compensates the computational expense.
Perfective and Corrective UML Pattern-based Design Maintenance with Design Constraints for Information Systems
(2007-12-12T16:28:05Z) Park, Jaeyong; Park, Jaeyong
Pattern-based design, the use of design pattern during the design process, has become widely used in the object-oriented community because of the reuse benefits that take less cost and effort, but result in high quality in software development and maintenance. However, design pattern defects can be injected in early design without mandatory control of the evolution of a pattern-based design and assessment of pattern-based designs after changes. It is crucial to maintain correct designs during early design maintenance because defects in early design may cause serious damage to software systems in later software development and maintenance. Hence, there is a need of a systematic design method for preventing design pattern defects being injected during pattern-based design maintenance so that the change results of pattern-based designs conform to the corresponding design patterns. Conventional Unified Modeling Language (UML) 2.0 design methods do not provide systematic ways of assessing pattern-based design conformance. Pattern Instance Changes with UML Profiles (PICUP) design method is developed as an improved design method for perfective and corrective UML pattern-based design maintenance and assessment. Design pattern in UML Profiles (DPUP) is developed for formal specification of a design pattern. DPUPs are used for instantiation, maintenance, and assessment of UML pattern-based designs. DPUPs, as the main part of PICUP design method, provide metamodel-level UML design constraints using UML stereotype notations and metamodel-level Object Constraint Language (OCL) design constraints. In this research, assessments of pattern-based designs in UML class diagram with the corresponding DPUPs enforce maintainers to make correct changes of the designs. Pattern-related information is annotated in pattern-based design using stereotype notations. Furthermore, the conformance checking of a given UML pattern-based design can be automated by using the assessment tool. An explanatory two-case study is used to evaluate the effectiveness of PICUP design method with DPUPs, and applied to (1) the Lexi document editor and (2) the ARENA game information system. Questionnaire answers and design pattern defect counts from the two-case study conducted by subject matter experts support the hypothesis that the PICUP method is an improved design method ensuring structural conformance of UML pattern-based designs to the corresponding design patterns during perfective and corrective design maintenance for information systems.
Mentors' Impact on the Development of Adaptability Skills via Experiential Learning
(2007-12-12T19:18:30Z) Kemp, Cary; Kemp, Cary
This research investigated the process of protégé development, focusing on the development of adaptability skills via experiential learning. Mentors facilitated skill development by challenging protégés during the conceptualization stage of learning. This finding highlights the importance of framebreaking and re-framing activities, and the role that mentors can play in promoting the development of new mental models. Mentors also facilitated development by frequently instructing protégés to intuitively grasp new concepts and to experiment with new skills. All mentoring functions except friendship were positively related to mentors' instruction to use experiential learning activities, suggesting that mentoring functions serve as platforms for learning activities. Career development facilitation and friendship were the only two functions directly related to skill development. Skill development was related to performance improvement and protégé satisfaction. Implications for mentor training and future research are discussed.
Authentic Leadership: Do We Really Need Another Leadership Theory?
(2007-12-12T19:24:16Z) Wood, Gabrielle; Wood, Gabrielle
The purpose of this study was to test the incremental validity of authentic leadership above and beyond existing leadership styles. Prior leadership research has focused primarily on transformational leadership. Recently, many researchers have observed that there are leaders who are effective and who do not conform to this style. Authentic leadership theory was advanced as an approach that may explain additional variance in leadership effectiveness. Participants included upper-year Cadets from the United States Military Academy (USMA) who served in leadership positions over lower-ranking Cadets. Cadet leadership styles were matched with personal attribute and performance scores to test a nomological network model of authentic leadership. Findings indicated some support for the notion that authentic leadership adds incremental validity over existing leadership styles, including transformational leadership. This study advances our understanding of authentic leadership theory and leadership effectiveness in challenging environments. Recommendations for future research in this area are provided.
A Study of the Effectiveness of an Alternative Licensure Program for Urban Elementary Teachers of English Language Learners
(2007-12-12T20:05:32Z) Wesley-Nero, Sabrina; Wesley-Nero, Sabrina
This study examined the qualifying portfolios of graduates of an alternative teacher licensure program to determine the extent to which the teachers evidenced effective instructional strategies for English language learners (ELLs). All study participants taught during the 2004-2005 school year in elementary classrooms in New York City public schools where at least 20% of the students were ELLs. The teachers in this study graduated from the Mercy College New Teacher Residency Program, a master's degree and alternative teacher licensure program. This study used the standards for the preparation of teachers of ELLs produced by Teachers of English to Speakers of Other Languages (TESOL) and the National Council for Accreditation of Teacher Education (NCATE) and the relevant research on the effective instruction of ELLs as an evaluative framework. Data revealed that the study participants did not satisfy the requirements of the TESOL/NCATE standards. However, the teachers demonstrated some instructional practices effective for ELLs as defined in the TESOL/NCATE standards and the research literature by implementing content-area instruction that was assessment-driven, standards-based, and differentiated according to students' academic needs.
Fighting Spirit
(2007-12-13T14:21:48Z) Pichocki, Jillian; Pichocki, Jillian
FIGHTING SPIRIT is the title of a thesis exhibition by Jillian Pichocki. It is a photographic series of large and mediumscale silver gelatin prints which focuses on the aging process of men engaged in the sport of boxing. In the past five decades, the socially accepted roles of men and women have changed. Whereas men often provided the sole source of income for the family; women served as the homemaker, maintaining the house, raising the children, and providing nourishment. The inspiration for this series stemmed from the relationship with my late grandfather who passed away in 1997. He was 79 when he died and it was his vitality and determination to remain selfsufficient that instilled my sense of compassion towards elderly men. I never met my grandmothers (both died from cancer when I was young) and therefore never witnessed, first hand, the physical affects of the aging process on a woman. Senior years can be difficult for many reasons. However, by pairing the fragility of age with the machismo associated with boxing allowed me to examine, metaphorically, the strength that exists within. More specifically, for the men of this series who once radiated strength and independence. This work renewed their perspective on life, as well as demonstrate, what it means to have a “fighting spirit.” My thesis will explain the journey that led to choosing to work with this subject matter. It will also explain the influences and technical processes involved with the photographic medium used.
Method for Deriving Multi-factor Models for Predicting Airport Delays
(2007-12-13T18:41:05Z) Xu, Ning; Xu, Ning
Traffic Flow Manage ament (TFM), in coordination with Airline Operation Centers (AOC), manage the arrival and departure flow of aircraft at the nations airports based on the airport Arrival and Departure rates for each 15 minute segment throughout the day. The management of traffic flow has become so efficient in the U.S., that approximately 95% of the delays now occur at the airports (not airborne). Inefficiencies in the traffic flow occur when non-traffic flow delays (e.g. carrier, turn-around, aircraft swapping and non-terminal area weather) are super-imposed on the traffic flow delays. Researchers have correlated these non-traffic flow delays at airports with sets of causal factors and have created models to predict aggregate delays at airports on the time scale of a day. To be consistent with the way traffic flow is managed, a model of causal factors of delays in 15 minute segments would provide the analytical basis for improving the efficiency of TFM. This dissertation describes the development of multi-factor models for predicting airport delays in 15 minute segments at 34 OEP airports. The models are created using Multivariate Adaptive Regression Splines (MARS). The models, generated using historic individual airport data, exhibit an accuracy of 5.3 minutes for generated delay across all the airports, and 2.1 minutes for absorbed delay across all the airports. A summary of the factors that drive the performance of each airport is provided. The sensitivity of each of the factors is also analyzed. Analysis of the models indicates that the factors that determine Airport Delays in 15 minute segments are unique to each airport. The most significant factors that generate delays at most of the nation's airports are Carrier Delay, GDP Delay at the outbound destination, and Departure Demand Ratio. Because of the relationship between these factors, and the propagation of delays throughout the network, the only way to mitigate system-wide delays is via a holistic network approach. The implications of these results are discussed. The potential benefits from this research include providing: (1) researchers and analysts a method to identify systemic causes of delays in the NAS and study the trends of influential factors; and (2) airlines and Air Traffic managers a means to evaluate predicted delays while executing Traffic Flow Management initiatives.
A Compiler-Based Approach to Implementing Smart Pointers
(2007-12-13T18:41:46Z) Hoskins, Stephen; Hoskins, Stephen
Because of the growing popularity of programming languages with garbage collectors, such as C# and Java, there is a clearly a desire for languages that support automated memory management. However, as a result of the inefficiencies of the garbage collectors of C# and Java, there is a requirement that programmers have a better understanding of the underlying implementations of the garbage collectors in order to make applications more robust or so that they can run on real-time systems. Using an implementation of smart pointers written from scratch, this paper attempts to address this problem by exploring techniques that are used by garbage collectors and ultimately concluding which features of object-oriented languages make the task of automating efficient garbage collection more difficult. As a result of the conclusions produced in this paper, it may be possible to create a brand new language with the simplicity and elegance of Java and the robustness and efficiency of C without the developer ever needing to perform memory management.

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