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Fiber Inline Pressure And Acoustic Sensor Fabricated With Femtosecond Laser, Yinan Zhang

Doctoral Dissertations

"Pressure and acoustic measurements are required in many industrial applications such as down-hole oil well monitoring, structural heath monitoring, engine monitoring, study of aerodynamics, etc. Conventional sensors are difficult to apply due to the high temperature, electromagnetic-interference noise and limited space in such environments. Fiber optic sensors have been developed since the last century and have proved themselves good candidates in such harsh environment. This dissertation aims to design, develop and demonstrate miniaturized fiber pressure/acoustic sensors for harsh environment applications through femtosecond laser fabrication. Working towards this objective, the dissertation explored two types of fiber inline microsensors fabricated by femtosecond …

Gas Dynamics And Heat Transfer In A Packed Pebble-Bed Reactor For The 4th Generation Nuclear Energy, Rahman Abdulmohsin

Doctoral Dissertations

"Proper analyses of axial dispersion and mixing of the coolant gas flow and heat transport phenomena in the dynamic core of nuclear pebble-bed reactors pose extreme challenges to the safe design and efficient operation of these packed pebble-bed reactors.

The main objectives of the present work are advancing the knowledge of the coolant gas dispersion and extent of mixing and the convective heat transfer coefficients in the studied packed pebble-beds. The study also provides the needed benchmark data for modeling and simulation validation. Hence, a separate effect pilot-plant scale and cold-flow experimental setup was designed, developed and used to carry …

Geochemical And Isotopic Characterization Of Lead In Fugitive Dust From Unsurfaced Roads In Missouri, Emitt C. Witt

Doctoral Dissertations

"Eighteen unsurfaced roadways in Missouri's rural Ozark region were sampled to characterize the differences in trace element and isotopic chemistry to determine if there is a human health concern with inhaling and/or ingestion of fugitive dust generated by a moving vehicle. Road reaches were selected to represent those in similar rural areas with and without the presence of mining activity--13 roads were selected in the Viburnum Trend (VT) resource mining area and five were located to the southwest of the mining areas. Samples were collected using a novel cyclonic fugitive dust sampler (patent pending) that collects a composite sample from …

Optimized Techniques For Real-Time Microwave And Millimeter Wave Sar Imaging, Joseph T. Case

Doctoral Dissertations

"Microwave and millimeter wave synthetic aperture radar (SAR)-based imaging techniques, used for nondestructive evaluation (NDE), have shown tremendous usefulness for the inspection of a wide variety of complex composite materials and structures. Studies were performed for the optimization of uniform and nonuniform sampling (i.e., measurement positions) since existing formulations of SAR resolution and sampling criteria do not account for all of the physical characteristics of a measurement (e.g., 2D limited-size aperture, electric field decreasing with distance from the measuring antenna, etc.) and nonuniform sampling criteria supports sampling below the Nyquist rate. The results of these studies demonstrate optimum sampling given …

Phytoforensics On Energetics: Novel Plant Tissue Measure Approach And Modeling, Yuan Yuan

Doctoral Dissertations

"Explosives and energetics are common soil and groundwater pollutions. This research was to develop novel phytoforensics approaches on energetics. Four different plants species, including woody perennial trees and monocot grasses, were planted both in soil and sand reactors with continuous exposure to a mixture of explosives in the greenhouse. Time dependent assessments were carried out to determine kinetic mechanisms of uptake, transport and accumulation. Plant concentrations were analyzed by both traditional solvent extraction and novel sap analysis methods. A dynamic soil-plant system model was developed to quantify the relationship between tissue concentration and soil pore water concentration for non-volatile organic …

Quantum Phase Transitions In Impurity Models And Percolating Lattices, Manal M. Al-Ali

Doctoral Dissertations

"This thesis investigates the influence of random disorder and dissipation on zero-temperature quantum phase transitions. Both phenomena can fundamentally change the character of the phases of a quantum many-particle system and of the transitions between them. If dissipation and disorder occur simultaneously in a system undergoing a quantum phase transition, particularly strong effects can be expected. In the first paper reproduced in this thesis, we study a single quantum rotor coupled to a sub-Ohmic dissipative bath. We find that this system undergoes a quantum phase transition from a delocalized phase to a localized phase as the dissipation strength is increased. …

Social-Context Based Routing And Security In Delay Tolerant Networks, Roy A. Cabaniss

Doctoral Dissertations

"Delay Tolerant Networks (DTNs) were originally intended for interplanetary communications and have been applied to a series of difficult environments: wireless sensor networks, unmanned aerial vehicles, and short-range personal communications. There is a class of such environments in which nodes follow semi-predictable social patterns, such as wildlife tracking or personal devices. This work introduces a series of algorithms designed to identify the social patterns present in these environments and apply this data to difficult problems, such as efficient message routing and content distribution. Security is also difficult in a mobile environment. This is especially the case in the event that …

Bioactive Glass Scaffolds For The Regeneration Of Load-Bearing Bone, Xin Liu

Doctoral Dissertations

"Biocompatible scaffolds that replicate the structure and function of bone would be ideal bone substitutes for structural bone loss, provided they have the requisite mechanical properties for reliable long-term loading. In this dissertation, strong porous scaffolds of silicate 13-93 bioactive glass, created with two different microstructures, were evaluated to determine their mechanical properties and their capacity to regenerate bone in a rat calvarial defect model. Scaffolds with an oriented microstructure of columnar pores were prepared by unidirectional freezing of camphene-based suspensions, followed by thermal annealing and sintering. By optimizing the freezing conditions, annealing time, and sintering temperature, constructs (porosity = …

Nanoscale Metal Oxide And Supported Metal Catalysts For Li-Air Battery, Kan Huang

Doctoral Dissertations

"The dissertation work focuses on research and development of durable nanoscale catalysts and supports for rechargeable Li-air batteries that use aqueous catholytes. Transition metal oxides, TiO₂ and Nb₂O₅ in particular, were prepared from a sol-gel process in the form of nanocoatings (5~50 nm) on carbon nanotubes (CNTs) and studied as catalyst supports. Carbon doping in the oxides and post annealing significantly increased their electronic conductivity. Pt catalyst on the support with TiO₂ (Pt/c-TiO₂/CNTs) showed a much better oxygen reduction reaction (ORR) activity than a commercial Pt on carbon black (Pt/C). Negligible loss ( …

Polarization And Opinion Analysis In An Online Argumentation System For Collaborative Decision Support, Ravi Santosh Arvapally

Doctoral Dissertations

"Argumentation is an important process in a collaborative decision making environment. Argumentation from a large number of stakeholders often produces a large argumentation tree. It is challenging to comprehend such an argumentation tree without intelligent analysis tools. Also, limited decision support is provided for its analysis by the existing argumentation systems. In an argumentation process, stakeholders tend to polarize on their opinions, and form polarization groups. Each group is usually led by a group leader. Polarization groups often overlap and a stakeholder is a member of multiple polarization groups. Identifying polarization groups and quantifying a stakeholder's degree of membership in …

Minimizing Formation Damage For Preformed Particle Gels Treatment In Mature Reservoirs, Mahmoud Omran Elsharafi

Doctoral Dissertations

"This research studied the effect of preformed particle gels (PPGs) on unswept, low-permeable zones/areas. The objective was to find methods that minimized the damage caused by PPGs on unswept, low-permeable zones/areas, thus improving PPG treatment efficiency. These results can help to identify of the best PPG types, particle sizes, and brine concentrations for specific reservoirs and treatments. This study used sandstone core samples with various degrees of permeability. Two types of particle gels, a strong Daqing gel (DQ) and a weak Liquiblock™ 40k gel (40K), were used, each with a different strength.

This research included two stages. Firstly, both a …

Modeling And Analysis Of Dynamic Behavior Of Adsorption Stratified Column Beds Packed With Partially Fractal Porous Adsorbent Particles, Min Li

Doctoral Dissertations

"In this work novel porous adsorbent media having partially fractal structures and stratified packed-beds are constructed and their dynamic performance with respect to their adsorptive capacity through the construction and solution of rigorous models is studied. The results show that conventional columns packed with partially fractal porous adsorbent particles provide larger breakthrough times and dynamic utilization of the adsorptive capacity of the column when compared with those of conventional columns employing conventional adsorbent particles which do not possess a partially fractal structure. Furthermore, stratified column beds exhibit superior species separation performance than conventional columns when they are packed with either …

2013 Spring Commencement, Georgia Southern University

Commencement Programs

No abstract provided.

Georgia Southern Magazine, Georgia Southern University

Georgia Southern Magazine

• Campus Growth
• An Evening with Laura Bush
• 'Sprung up from Sandy Earth'
• China's Roses
• Tee Time
• Learning to Overcome

Planar Waveguide With Left-Handed Material Guiding Film For Refractometry Applications, Taher M. El-Agez, Sofyan A. Taya, Mohamed M. Shabat, Hani M. Kullab

Turkish Journal of Physics

A symmetric 3-layer slab waveguide with a left-handed material as a guiding layer is examined analytically for cover refractive index detection. The TM mode dispersion relation of the proposed waveguide is investigated. The sensitivity of the proposed sensor to changes in the cover refractive index and the power flowing within each layer are presented. Some unusual features are found; for example, the sensitivity of the proposed sensor is negative. Moreover, the sensitivity improvement compared with the conventional 3-layer waveguide sensor is approximately a factor of 6.

Magnetic Wiggler-Assisted Third-Harmonic Generation Of A Gaussian Laser Pulse In Plasma, Hirdesh Sharma, Harsha Jaloree, Jetendra Parashar

Turkish Journal of Physics

A Gaussian laser pulse propagating through plasma in the presence of a magnetic wiggler produces third-harmonic radiation. The wiggler's magnetic field provides additional momentum required for phase matching. The required wiggler wave number is sensitive to pulse duration and amplitude. The efficiency of the process is significant at the instant at which the phase matching condition is satisfied.

Of Law And The Revolution, Lama Abu-Odeh

Georgetown Law Faculty Publications and Other Works

The Egyptian revolution is proving to be a very legal one. That is not to say that the revolution’s demands have been legalized, nor that Egypt’s law has been revolutionized, rather, the forces that have come to the fore since the toppling of Mubarak in Feb 2011 have chosen law as the privileged form through which to bargain with each other. The density of the legal back and fro has been overwhelming: constitutional amendments, constitutional supplementary declarations, parliamentary laws, legislative amendments, military decrees, court trials, constitutional court decisions overturning laws passed, conflicting decisions from various courts, presidential decrees, emergency laws …

Law, Liberty And The Rule Of Law (In A Constitutional Democracy), Imer Flores

Georgetown Law Faculty Publications and Other Works

In the hunt for a better--and more substantial--awareness of the “law,” The author intends to analyze the different notions related to the “rule of law” and to criticize the conceptions that equate it either to the sum of “law” and “rule” or to the formal assertion that “law rules,” regardless of its relationship to certain principles, including both “negative” and “positive” liberties. Instead, he pretends to scrutinize the principles of the “rule of law,” in general, and in a “constitutional democracy,” in particular, to conclude that the tendency to reduce the “democratic principle” to the “majority rule” (or “majority principle”), …

National Security Pedagogy: The Role Of Simulations, Laura K. Donohue

Georgetown Law Faculty Publications and Other Works

This article challenges the dominant pedagogical assumptions in the legal academy. It begins by briefly considering the state of the field of national security, noting the rapid expansion in employment and the breadth of related positions that have been created post-9/11. It considers, in the process, how the legal academy has, as an institutional matter, responded to the demand.

Part III examines traditional legal pedagogy, grounding the discussion in studies initiated by the American Bar Association, the Carnegie Foundation, and others. It suggests that using the law-writ-large as a starting point for those interested in national security law is a …

Representing Social Enterprise, Alicia E. Plerhoples

Georgetown Law Faculty Publications and Other Works

This article explores the representation of social enterprises—i.e., nonprofit and for-profit organizations whose managersstrategically and purposefully work to create social, environmental, and economic value or achieve a social good through the use of business techniques—in the Social Enterprise & Nonprofit Law Clinic at Georgetown University Law Center. Representation of social enterprises helps create a dynamic curriculum through which law students learn to merge corporate legal theory with transactional law practice. Through service to social enterprises, law students (i) learn about corporate governance and corporate legal theory as well as business models and mechanisms that support social and environmental value creation …

Narratives Of The European Crisis And The Future Of (Social) Europe, Philomila Tsoukala

Georgetown Law Faculty Publications and Other Works

This article examines two distinct types of narratives prevalent in academic writing and popular press regarding the causes of the crisis in Europe. The first type, a morality tale, attributes the crisis to profligate southern states that refused to abide by the strictures of the Stability and Growth Pact. The second type is focused on the structural reasons for the crisis, emphasizing the nature of the European Union as a non-optimal currency area, and the euro as a factor in the creation of trade imbalances and competitiveness problems within the euro zone. Each type of narrative suggests a different type …

A Systematic Plan For Firearms Law Reform, Katherine L. Record, Lawrence O. Gostin

Georgetown Law Faculty Publications and Other Works

Tragedy after tragedy has drawn the nation’s attention towards gun violence. Yet the murder of 20 school children in Newtown, CT has done more to drive the national dialogue on gun control than any preceding mass shooting, not to mention the endemic murderous violence that plagues city streets day in and out. President Obama has responded by calling on Congress to (1) close background check loopholes; (2) ban assault weapons and high-capacity magazines; and (3) improve mental health services. All of these measures are necessary to curb gun violence. Yet, in a nation with more firearms per capita than anywhere …

Egypt's New Constitution: The Islamist Difference, Lama Abu-Odeh

Georgetown Law Faculty Publications and Other Works

The paper discusses the distributional impact of the rules of the new Egyptian constitution (2012). It specifically addresses the way such rules, substantive and (potentially) procedural, can influence Egyptian law's identity and the underlying relations between the state and individuals and among individuals themselves that such identity implies.

Distribution And Occurrence Of Escherichia Coli In Water And Sediments At Grand Glaize Beach In Lake Of The Ozarks State Park, Jordan Lee Wilson

Masters Theses

"Public swimming beaches at the Lake of the Ozarks State Park (LOSP) are popular vacationing spots for many Missourians; however, on several occasions Escherichia coli (E. coli) concentrations have exceeded standards set by the Missouri Department of Natural Resources (MDNR). Exceedances lead to beach closures which not only represent a potential public health threat but are also detrimental to the local economy and the public's perception of the lake's general water quality. In a collaborative effort between Missouri S&T, the United States Geological Survey (USGS) and the MDNR, an in-depth, two-summer study was conducted which included collection of …

Processing Of Continuous Fiber Reinforced Ceramic Composites For Ultra High Temperature Applications Using Organosilicon Polymer Precursors, James Robert Nicholas

Masters Theses

"The current work is on the development of continuous fiber reinforced ceramic materials (CFCCs) for use in ultra high temperature applications. These applications subject materials to extremely high temperatures (> 2000⁰C). Monolithic ceramics are currently being used for these applications, but the tendency to fail catastrophically has driven the need for the next generation of material. Reinforcing with continuous fibers significantly improves the toughness of the monolithic materials; however, this is a manufacturing challenge. The development of commercial, low-viscosity preceramic polymers provides new opportunities to fabricate CFCCs. Preceramic polymers behave as polymers at low temperatures and are transformed into ceramics …

Computational Fluid Dynamics Flow Comparison Between Openhole Sleeve And Plug-And-Perf Completion In A Hydraulic Fractured Horizontal Well, Viriyah Theppornprapakorn

Masters Theses

"Multi-stage hydraulic fracture completions in horizontal wells have facilitated economic development of natural gas from unconventional and tight gas reservoirs.Industry has relied on two horizontal multi-stage completion technologies: cemented and perforated liner or Plug-and-perf method and Openhole Sleeve Multi-stage method. Each method has its own advantages and disadvantages. However, one of the most important questions is which method yields better gas production? Computation fluid dynamics (CFD) is a powerful tool for solving complex fluid flow problems. In well completion design, CFD plays a significant role aiding the completion engineers on making decision on well completion methods. In this study, a …

The Historical Contingencies Of Conflict Resolution, Carrie Menkel-Meadow

Georgetown Law Faculty Publications and Other Works

This article reviews the historical contingency of theory and practice in conflict engagement. World War II and the Cold War produced adversarial, distributive, competitive, and scarce resources conceptions of negotiation and conflict resolution, as evidenced by game theory and negotiation practice. More recent and more optimistic theory and practice has focused on party needs and interests and hopes for more party-tailored, contingent, flexible, participatory and more integrative and creative solutions for more than two disputants to a conflict. The current challenges of our present history are explored: continued conflict in both domestic and international settings, the challenge of “scaling up” …

Preserving Privacy In A Digital Age: Lessons Of Comparative Constitutionalism, David Cole

Georgetown Law Faculty Publications and Other Works

In the modern age, we increasingly live our lives through, and accompanied by, digital media. Virtually every transaction or communication that uses such media, as well as every move of mobile phone owners, is recorded. Computers are able to store, transmit, and analyze the data as never before, drawing on multiple sources to construct an intimate picture of our interests, contacts, travels and desires. Private data-mining services, most often used for commercial advertising purposes, can determine: what we read, listen to, and look at; where we travel to, shop, and dine; and with whom we speak or associate. Meanwhile, social …

“[This] I Know From My Grandfather”: The Battle For Admissibility Of Indigenous Oral History As Proof Of Tribal Land Claims, Hope M. Babcock

Georgetown Law Faculty Publications and Other Works

A major obstacle indigenous land claimants must face is the application of federal evidentiary rules, like the hearsay doctrine, which block the use of oral history to establish legal claims. It is often oral history and stories that tribes rely upon as evidence to support their claims, reducing substantially the likelihood of a tribe prevailing. Indigenous oral history presents unique challenges to judges when faced with its admissibility. Canadian courts have largely overcome these challenges by interpreting evidentiary rules liberally, in favor of the aborigines. As such, Canadian aborigines have enjoyed greater land claim success than indigenous claimants in the …

Civil Rights For The Twenty-First Century: Lessons From Justice Thurgood Marshall's Race-Transcending Jurisprudence, Sheryll Cashin

Georgetown Law Faculty Publications and Other Works

This Essay pays tribute to justice Thurgood Marshall's race-transcending vision of universal human dignity, and explores the importance of building cross-racial alliances to modern civil rights advocacy. justice Marshall's role as a "Race Man" is evident in much of his jurisprudence, where he fought for years to promote equal opportunity and equal justice. As an advocate for all marginalized people, justice Marshall viewed equal justice as transcending race, and this Essay suggests that the multi-racial coalition that supported President Obama aligns with Marshall's vision. The Essay evaluates the civil rights movement through the lens of Justice Marshall's equality analysis, and …