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Studies Of Pentaquarks And Of Noncommutative Field Theory, Vahagn Nazaryan
Studies Of Pentaquarks And Of Noncommutative Field Theory, Vahagn Nazaryan
Dissertations, Theses, and Masters Projects
Several experiments reported seeing evidence in their data of a new particle, the strangeness +1 Theta+ pentaquark made of four quarks and an antiquark. In the first few chapters of this dissertation we study four-quark-antiquark systems within the framework of a constituent quark model. We describe the Theta+ as a member of a spin-½ pentaquark antidecuplet. For both parity-odd, and parity-even antidecuplets we derive useful decompositions of the quark model wave functions that allow for easy computation of color-flavor-spin-orbital matrix elements, and we compute mass splittings within the antidecuplet. We study parity-even antidecuplet in an effective theory with dominant flavor-spin …
Ichthyofaunal And Dietary Analysis Of Sympatric Piscivores In A Chesapeake Bay Littoral Zone: Including Bioenergetic Models Of Growth And Diel Temperature Sanctuary Use, Christian Harding Hager
Ichthyofaunal And Dietary Analysis Of Sympatric Piscivores In A Chesapeake Bay Littoral Zone: Including Bioenergetic Models Of Growth And Diel Temperature Sanctuary Use, Christian Harding Hager
Dissertations, Theses, and Masters Projects
The first section of this dissertation describes the ichthyofaunal community of a mesohaline Chesapeake Bay April--November. Fish assemblages were sampled using two seine gears, a small seine that sampled 352 m 2 and a 914m haul-seine that sampled 144,473 m2. The small seine collected 32 finfish species. The larger gear captured 31 finfish species, including 17 that were not sampled by small gear. Sampled diversity was greater but density estimates were similar to those determined previously by other investigators using flume-net, drop-ring, and otter trawl techniques. Nocturnal abundance of larger fishes far exceeded daylight. Fish abundance and size distribution varied …
Runtime Support For Load Balancing Of Parallel Adaptive And Irregular Applications, Kevin James Barker
Runtime Support For Load Balancing Of Parallel Adaptive And Irregular Applications, Kevin James Barker
Dissertations, Theses, and Masters Projects
Applications critical to today's engineering research often must make use of the increased memory and processing power of a parallel machine. While advances in architecture design are leading to more and more powerful parallel systems, the software tools needed to realize their full potential are in a much less advanced state. In particular, efficient, robust, and high-performance runtime support software is critical in the area of dynamic load balancing. While the load balancing of loosely synchronous codes, such as field solvers, has been studied extensively for the past 15 years, there exists a class of problems, known as asynchronous and …
Efficient Caching Algorithms For Memory Management In Computer Systems, Song Jiang
Efficient Caching Algorithms For Memory Management In Computer Systems, Song Jiang
Dissertations, Theses, and Masters Projects
As disk performance continues to lag behind that of memory systems and processors, fully utilizing memory to reduce disk accesses is a highly effective effort to improve the entire system performance. Furthermore, to serve the applications running on a computer in distributed systems, not only the local memory but also the memory on remote servers must be effectively managed to minimize I/O operations. The critical challenges in an effective memory cache management include: (1) Insightfully understanding and quantifying the locality inherent in the memory access requests; (2) Effectively utilizing the locality information in replacement algorithms; (3) Intelligently placing and replacing …
Characterization Of Transient Behaviors In A Colliding Pulse Mode-Locked (Cpm) Laser, Wei Yang
Characterization Of Transient Behaviors In A Colliding Pulse Mode-Locked (Cpm) Laser, Wei Yang
Dissertations, Theses, and Masters Projects
A colliding pulse mode-locked (CPM) laser achieves sub-picosecond operation by synchronizing two counter-propagating pulse trains to form a standing wave in a thin absorber jet. When properly aligned, these lasers maintain mode-locking for more than 100 seconds (1010 pulses), but eventually cease mode-locking for short periods of time. This thesis examines the characteristics of these transient events, when CPM mode-locking ceases (dropout) and when it resumes (dropin). The dropout is an apparently rapid event, typically lasting no longer than 5 microseconds or less than 500 pulses. The dropin takes significantly longer time, often has structure, and has a clear power …
An Economic Assessment Of Reducing Incidental Capture Of Sea Turtles In The Northwest Atlantic Pelagic Longline Fishery, Tara L. Scott
An Economic Assessment Of Reducing Incidental Capture Of Sea Turtles In The Northwest Atlantic Pelagic Longline Fishery, Tara L. Scott
Dissertations, Theses, and Masters Projects
No abstract provided.
Optimizing Combat Capabilities By Modeling Combat As A Complex Adaptive System, Steven Mains
Optimizing Combat Capabilities By Modeling Combat As A Complex Adaptive System, Steven Mains
Dissertations, Theses, and Masters Projects
Procuring combat systems in the Department of Defense is a balancing act where many variables, only some under control of the department, shift simultaneously. Technology changes non-linearly, providing new opportunities and new challenges to the existing and potential force. Money available changes year over year to fit into the overall US Government budget. Numbers of employees change through political demands rather than by cost-effectiveness considerations. The intent is to provide the best mix of equipment to field the best force against an expected enemy while maintaining adequate capability against the unexpected. Confounding this desire is the inability of current simulations …
Bird Conservation Value Of Golf Courses, Joshua Elliott Leclerc
Bird Conservation Value Of Golf Courses, Joshua Elliott Leclerc
Dissertations, Theses, and Masters Projects
No abstract provided.
Spontaneous Pulse Formation In Bistable Systems, George A. Andrews
Spontaneous Pulse Formation In Bistable Systems, George A. Andrews
Dissertations, Theses, and Masters Projects
This thesis considers localized spontaneous pulse formation in nonlinear, dissipative systems that are far from equilibrium and which exhibit bistability. It is shown that such pulses can form in systems that are dominated by the combined effects of: (1) a saturable amplifying or gain region, (2) a saturable absorbing or loss region, and (3) cavity effects. Analysis is based upon novel models for both an inertialess material in which the absorber responds instantaneously and inertial material in which there is temporal delay in the response. Additionally, we include the situation where the material does not fully relax between pulses, i.e. …
Solid State Nmr Characterization Of Conductive Polyanilines, Yanina Anatolievna Goddard
Solid State Nmr Characterization Of Conductive Polyanilines, Yanina Anatolievna Goddard
Dissertations, Theses, and Masters Projects
Different forms of ring deuterated polyaniline with different conductivity have been characterized by solid state deuteron nuclear magnetic resonance.;Quadrupole echo (QE) spectra of all forms of polyaniline consist of a superposition of lineshapes for nearly rigid aromatic rings and a small fraction of rings which undergo fast 180?? flips. The intensity of the fast flipping component is temperature dependent and different for conductive emeraldine salt (ES) and non-conductive emeraldine base (EB). This is a manifestation of the different structure and morphology of these polymers.;Simultaneous measurements of QE lineshapes and the relaxation time anisotropies allowed an accurate description of motion in …
On Certain Sets Of Matrices: Euclidean Squared Distance Matrices, Ray-Nonsingular Matrices And Matrices Generated By Reflections, Thomas W. Milligan
On Certain Sets Of Matrices: Euclidean Squared Distance Matrices, Ray-Nonsingular Matrices And Matrices Generated By Reflections, Thomas W. Milligan
Dissertations, Theses, and Masters Projects
In this dissertation, we study three different sets of matrices. First, we consider Euclidean distance squared matrices. Given n points in Euclidean space, we construct an n x n Euclidean squared distance matrix by assigning to each entry the square of the pairwise interpoint Euclidean distance. The study of distance matrices is useful in computational chemistry and structural molecular biology. The purpose of the first part of the thesis is to better understand this set of matrices and its different characterizations so that a number of open problems might be answered and known results improved. We look at geometrical properties …
Structural Model Checking, Radu Siminiceanu
Structural Model Checking, Radu Siminiceanu
Dissertations, Theses, and Masters Projects
The introduction of symbolic approaches, based on Binary Decision Diagrams (BDD), to Model Checking has led to significant improvements in Formal Verification, by allowing the analysis of very large systems, such as complex circuit designs. These were previously beyond the reach of traditional, explicit methods, due to the state space explosion phenomenon. However, after the initial success, the BDD technology has peaked, due to a similar problem, the BDD explosion.;We present a new approach to symbolic Model Checking that is based on exploiting the system structure. This technique is characterized by several unique features, including an encoding of states with …
Building Internet Caching Systems For Streaming Media Delivery, Songqing Chen
Building Internet Caching Systems For Streaming Media Delivery, Songqing Chen
Dissertations, Theses, and Masters Projects
The proxy has been widely and successfully used to cache the static Web objects fetched by a client so that the subsequent clients requesting the same Web objects can be served directly from the proxy instead of other sources faraway, thus reducing the server's load, the network traffic and the client response time. However, with the dramatic increase of streaming media objects emerging on the Internet, the existing proxy cannot efficiently deliver them due to their large sizes and client real time requirements.;In this dissertation, we design, implement, and evaluate cost-effective and high performance proxy-based Internet caching systems for streaming …
Measurement Of The Branching Fraction For Neutral Kaon(Long) Decaying To Muon-Electron-Positron, Andrew J. Norman
Measurement Of The Branching Fraction For Neutral Kaon(Long) Decaying To Muon-Electron-Positron, Andrew J. Norman
Dissertations, Theses, and Masters Projects
This dissertation describes the measurement of the decay of the long lived neutral kaon into two muons and two electrons. The measurement was performed using the data taken during experiment E871 which was performed on the B5 beamline at the Alternating Gradient Synchrotron (AGS) of the Brookhaven National Laboratory (BNL). The branching ratio B( K0L → mu+mu-e +e-) is sensitive to the absorptive portion of the long distance amplitude for decays of the form K0L → ℓ+ℓ- and can be used to properly extract the short distance weak interaction amplitudes from the dileptonic events.;Measurement of K0L → mu+mu-e +e- additionally …
Lookahead Scheduling In A Real-Time Context: Models, Algorithms, And Analysis, Benjamin J. Coleman
Lookahead Scheduling In A Real-Time Context: Models, Algorithms, And Analysis, Benjamin J. Coleman
Dissertations, Theses, and Masters Projects
Our research considers job scheduling, a special type of resource assignment problem. For example, at a cross-docking facility trucks must be assigned to doors where they will be unloaded. The cargo on each truck has various destinations within the facility, and the unloading time for a truck is dependent on the distance from the assigned door to these destinations. The goal is to assign the trucks to doors while minimizing the amount of time to unload all trucks.;We study scheduling algorithms for problems like the cross-docking example that are different from traditional algorithms in two ways. First, we utilize real-time, …
Binding Studies On Molecularly Imprinted Polymers, Lucy Yue Hu
Binding Studies On Molecularly Imprinted Polymers, Lucy Yue Hu
Dissertations, Theses, and Masters Projects
Molecular imprinting is a rapidly developing technique for preparation of polymeric materials that are capable of molecular recognition for selective separation and chemical identification. to prepare molecularly imprinted polymers (MIPs), a functional monomer and a crosslinker are polymerized in the presence of a template molecule. Then the template is extracted leaving sites which are complementary in both shape and chemical functionality to those of the template. This resin then becomes capable of selectively absorbing the template species. Because of MIPs' stability, predesigned selectivity, and easy preparation, they have been used for separation, sensor, drug development and directed synthesis.;In this study, …
Files As First-Class Objects In Fault -Tolerant Concurrent Systems, Robert Edwin Matthews
Files As First-Class Objects In Fault -Tolerant Concurrent Systems, Robert Edwin Matthews
Dissertations, Theses, and Masters Projects
Concurrent systems are used in applications where multiple processors are needed to complete tasks within a reasonable amount of time, or where the data sets involved will not fit within the main memory of a single computer. Because of their reliance on multiple machines, such systems are proportionally more vulnerable to both hardware and software induced failures. Fault-tolerance schemes are used to recover some earlier consistent state of the system after such a failure.;One important technique used to achieve fault-tolerance is checkpointing and rollback-recovery. In this thesis, we present a method for efficiently and transparently incorporating the part of the …
Ultraviolet Sources For Advanced Applications In The Vacuum Uv And Near Uv, Sheng Peng
Ultraviolet Sources For Advanced Applications In The Vacuum Uv And Near Uv, Sheng Peng
Dissertations, Theses, and Masters Projects
This dissertation documents a systematic study consisting of experimental investigations and theoretical analyses of intense ultraviolet sources in VUV and near-UV. Some engineering issues regarding two prototypes of electrodeless lamps using rf and microwave are discussed.;Various excimers that produce intense UV light are investigated, including: (1) A benchmark Xe2 excimer which has been proven to be very efficient in our novel rf capacitively coupled discharge lamp; (2) A rarely studied excimer, KrI, which suffers from predissociation and was reported to be very weak or invisible by most of other studies; (3) XeI excimer whose emission dominates around 253 nm and …
Pathobiology Of Mycobacteria In Striped Bass (Morone Saxatilis), David T. Gauthier
Pathobiology Of Mycobacteria In Striped Bass (Morone Saxatilis), David T. Gauthier
Dissertations, Theses, and Masters Projects
Striped bass (Morone saxatilis) in Chesapeake Bay, USA, are experiencing an epizootic of mycobacteriosis. This disease, caused by bacteria in the genus Mycobacterium, causes granulomatous lesions of the skin and viscera. Diseased fish are often emaciated, and fish with skin lesions may be significantly disfigured. The overall goal of this work was to examine aspects of the pathobiology of mycobacteria in striped bass via laboratory exposure studies and cellular assays. Striped bass were injected intraperitoneally with a sublethal dose of Mycobacterium marinum, M. shottsii, or M. gordonae and sampled for histology and bacteriology at regular intervals to 45 weeks post-injection …
A Study Of The Eastern Oyster, Crassostrea Virginica: (1) Dermo Tolerance, Survival, Growth, Condition And Hsp70 Expression In Different Geographic Stocks; (2) Heat Tolerance And Effects Of Sublethal Heat Shock On Survival And Hsp70 Expression Of Infected And Uninfected Oysters, Vincent G. Encomio
Dissertations, Theses, and Masters Projects
The diseases Dermo and MSX have devastated Chesapeake Bay populations of the eastern oyster, Crassostrea virginica. The protozoan Perkinsus marinus, which causes Dermo, is particularly problematic since it persists over a wide range of salinities and temperatures. An objective of this dissertation was to determine whether specific wild oyster stocks had developed natural resistance to Dermo and if several parameters (survival, growth, condition and energy reserves) were associated with resistance. Another objective was to characterize heat shock protein (hsp70) expression in the eastern oyster. Heat shock proteins such as hsp70 protect organisms from thermal stress and other stressors, and this …
Natural Dermo Resistance And Related Defense Mechanisms In Eastern Oysters, Crassostrea Virginica, With Implications For Restoration, Shawn Michael Stickler
Natural Dermo Resistance And Related Defense Mechanisms In Eastern Oysters, Crassostrea Virginica, With Implications For Restoration, Shawn Michael Stickler
Dissertations, Theses, and Masters Projects
American oyster (Crassostrea virginica) stocks on the East Coast in general, and in Chesapeake Bay in particular, have been in decline over the past half-century in large part due to Dermo disease, caused by the protist parasite Perkinsus marinus. Efforts to restore oysters for their ecological and economic value have centered on the development and use of hatchery-based seed selectively bred for disease resistance. Selective breeding could benefit from the incorporation of oysters from wild stocks that have developed "natural Dermo resistance", but few such stocks have been identified and verified. This dissertation describes reciprocal common-garden experiments carried out at …
Control Of Integrable Hamiltonian Systems And Degenerate Bifurcations, Christopher W. Kulp
Control Of Integrable Hamiltonian Systems And Degenerate Bifurcations, Christopher W. Kulp
Dissertations, Theses, and Masters Projects
In this dissertation, we study the control of near-integrable systems. A near-integrable system is one whose phase space has a similar structure to an integrable system during short time periods and for some parameter regime. We begin by studying the control of integrable Hamiltonian systems. The controller targets an exact solution to the integrable system using dissipative and conservative terms. We find that a Takens-Bogdanov bifurcation occurs in the limit of no dissipative control. The presence of a Takens-Bogdanov bifurcation implies that the control is highly susceptible to noise. We illustrate our results using a two- and four-dimensional integrable systems …
Synthesis And Characterization Of Polyimide Residuum, Friable Balloons, Microspheres And Foams, Erik Saul Weiser
Synthesis And Characterization Of Polyimide Residuum, Friable Balloons, Microspheres And Foams, Erik Saul Weiser
Dissertations, Theses, and Masters Projects
In order to meet requirements of future NASA systems for advanced polymeric cellular materials, research was undertaken to develop the next generation of polyimide foams which could be utilized as a reusable structural insulation on future Reusable Launch Vehicle (RLV) Programs. This research activity focused on developing polyimide foam and foam structures which were made using monomeric solutions or salt solutions formed from the reaction of a dianhydride and diamine dissolved in a mixture of foaming agents and alkyl alcohols. This process produced a precursor solid residuum which could then be manufactured into foams, friable balloons and microspheres. Polyimide foams …
Reproductive Biology Of American Shad, Alosa Sapidissima, In The Mattaponi River, Aaron Reid Hyle
Reproductive Biology Of American Shad, Alosa Sapidissima, In The Mattaponi River, Aaron Reid Hyle
Dissertations, Theses, and Masters Projects
No abstract provided.
Stability At Hydrothermal-Vent Mussel Beds: Dynamics At Hydrothermal Vents: Evidence For Stable Macrofaunal Communities In Mussel Beds On The Northern East Pacific Rise, Jennifer Carolyn Dreyer
Stability At Hydrothermal-Vent Mussel Beds: Dynamics At Hydrothermal Vents: Evidence For Stable Macrofaunal Communities In Mussel Beds On The Northern East Pacific Rise, Jennifer Carolyn Dreyer
Dissertations, Theses, and Masters Projects
No abstract provided.
Dynamic Adaptation To Cpu And Memory Load In Scientific Applications, Richard Tran Mills
Dynamic Adaptation To Cpu And Memory Load In Scientific Applications, Richard Tran Mills
Dissertations, Theses, and Masters Projects
As commodity computers and networking technologies have become faster and more affordable, fairly capable machines have become nearly ubiquitous while the effective "distance" between them has decreased as network connectivity and capacity has multiplied. There is considerable interest in developing means to readily access such vast amounts of computing power to solve scientific problems, but the complexity of these modern computing environments pose problems for conventional computer codes designed to run on a static, homogeneous set of resources. One source of problems is the heterogeneity that is naturally present in these settings. More problematic is the competition that arises between …
Documenting The Suspended And Bottom Sediment Dynamics Of A Two Estuarine Turbidity Maximum System Using 7be And 234th, Heidi M. Romine
Documenting The Suspended And Bottom Sediment Dynamics Of A Two Estuarine Turbidity Maximum System Using 7be And 234th, Heidi M. Romine
Dissertations, Theses, and Masters Projects
No abstract provided.
Parasitism In Deep-Sea Chemosynthetic Mussels: Parasitism In Bathymodiolus Mussels From Deep-Sea Seep And Hydrothermal Vents, Megan E. Ward
Parasitism In Deep-Sea Chemosynthetic Mussels: Parasitism In Bathymodiolus Mussels From Deep-Sea Seep And Hydrothermal Vents, Megan E. Ward
Dissertations, Theses, and Masters Projects
No abstract provided.
Dual Energy Scanning Beam X -Radiography, Randolph Frank Wojcik
Dual Energy Scanning Beam X -Radiography, Randolph Frank Wojcik
Dissertations, Theses, and Masters Projects
Dual energy X-radiography is a method first developed in the mid-1970's by which one uses the information contained in the energy spectrum of the transmitted X-ray flux through an object. With this information one can distinguish the types of materials present in a radiograph and thus allow a computer to subtract them from the image enhancing the contrast of the remaining materials. Using this method, one can see details, which would have been hidden by overlying structures of other materials such as seen in radiographs of parts, made up of mixtures of metals and composites. There is also great interest …
Status And Demographic Analysis Of The Dusky Shark, Carcharhinus Obscurus, In The Northwest Atlantic, Jason G. Romine
Status And Demographic Analysis Of The Dusky Shark, Carcharhinus Obscurus, In The Northwest Atlantic, Jason G. Romine
Dissertations, Theses, and Masters Projects
No abstract provided.