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Plasmon Enhanced Near-Field Interactions In Surface Coupled Nanoparticle Arrays For Integrated Nanophotonic Devices, Amitabh Ghoshal 2010 University of Central Florida

Plasmon Enhanced Near-Field Interactions In Surface Coupled Nanoparticle Arrays For Integrated Nanophotonic Devices, Amitabh Ghoshal

Electronic Theses and Dissertations

The current thrust towards developing silicon compatible integrated nanophotonic devices is driven by need to overcome critical challenges in electronic circuit technology related to information bandwidth and thermal management. Surface plasmon nanophotonics represents a hybrid technology at the interface of optics and electronics that could address several of the existing challenges. Surface plasmons are electronic charge density waves that can occur at a metal-dielectric interface at optical and infrared frequencies. Numerous plasmon based integrated optical devices such as waveguides, splitters, resonators and multimode interference devices have been developed, however no standard integrated device for coupling light into nanoscale optical circuits ...


Species Composition And Spatiotemporal Pattern Of The Seed Bank And Vegetation In Native And Degraded Florida Rosemary Scrub, Jennifer J. Navarra 2010 University of Central Florida

Species Composition And Spatiotemporal Pattern Of The Seed Bank And Vegetation In Native And Degraded Florida Rosemary Scrub, Jennifer J. Navarra

Electronic Theses and Dissertations

The soil seed bank plays a dynamic role in the regeneration of plant communities after natural and anthropogenic disturbance. In this thesis, I addressed how disturbances influence the vegetation and seed bank of Florida rosemary scrub. In Chapter One I evaluated changes in species composition and spatiotemporal pattern of the vegetation and seed bank along a gradient of disturbance. During the summers and winters of 2007-2009 percent ground cover and seed bank species composition were assessed among replicates of three vegetation types subjected to minimal, moderate, and extreme anthropogenic disturbance (native rosemary scrub, degraded scrub, and agriculturally improved pasture, respectively ...


Development Of Optical Coherence Tomography For Tissue Diagnostics, Panomsak Meemon 2010 University of Central Florida

Development Of Optical Coherence Tomography For Tissue Diagnostics, Panomsak Meemon

Electronic Theses and Dissertations

Microvasculature can be found in almost every part of the human body, including the internal organs. Importantly, abnormal changes in microvasculature are usually related to pathological development of the tissue cells. Monitoring of changes in blood flow properties in microvasculature, therefore, provides useful diagnostic information about pathological conditions in biological tissues as exemplified in glaucoma, diabetes, age related macular degeneration, port wine stains, burn-depth, and potentially skin cancer. However, the capillary network is typically only one cell in wall thickness with 5 to 10 microns in diameter and located in the dermis region of skin. Therefore, a non-invasive flow imaging ...


A Novel Weighted-Graph-Based Grouping Algorithm For Metadata Prefetching, Peng Gu, Jun Wang, Yifeng Zhu, Hong Jiang, Pengju Shang 2010 Microsoft Corporation

A Novel Weighted-Graph-Based Grouping Algorithm For Metadata Prefetching, Peng Gu, Jun Wang, Yifeng Zhu, Hong Jiang, Pengju Shang

CSE Journal Articles

Although data prefetching algorithms have been extensively studied for years, there is no counterpart research done for metadata access performance. Existing data prefetching algorithms, either lack of emphasis on group prefetching, or bearing a high level of computational complexity, do not work well with metadata prefetching cases. Therefore, an efficient, accurate, and distributed metadata-oriented prefetching scheme is critical to leverage the overall performance in large distributed storage systems. In this paper, we present a novel weighted-graph-based prefetching technique, built on both direct and indirect successor relationship, to reap performance benefit from prefetching specifically for clustered metadata servers, an arrangement envisioned ...


Communication-Aware Load Balancing For Parallel Applications On Clusters, Xiao Qin, Hong Jiang, Adam Manzanares, Xiaojun Ruan, Shu Yin 2010 Auburn University

Communication-Aware Load Balancing For Parallel Applications On Clusters, Xiao Qin, Hong Jiang, Adam Manzanares, Xiaojun Ruan, Shu Yin

CSE Journal Articles

Cluster computing has emerged as a primary and cost-effective platform for running parallel applications, including communication-intensive applications that transfer a large amount of data among the nodes of a cluster via the interconnection network. Conventional load balancers have proven effective in increasing the utilization of CPU, memory, and disk I/O resources in a cluster. However, most of the existing load-balancing schemes ignore network resources, leaving an opportunity to improve the effective bandwidth of networks on clusters running parallel applications. For this reason, we propose a communication-aware load-balancing technique that is capable of improving the performance of communication-intensive applications by ...


Xlp: A Cross-Layer Protocol For Efficient Communication In Wireless Sensor Networks, Mehmet C. Vuran, Ian F. Akyildiz 2010 IEEE

Xlp: A Cross-Layer Protocol For Efficient Communication In Wireless Sensor Networks, Mehmet C. Vuran, Ian F. Akyildiz

CSE Journal Articles

Severe energy constraints of battery-powered sensor nodes necessitate energy-efficient communication in Wireless Sensor Networks (WSNs). However, the vast majority of the existing solutions is based on classical layered protocols approach, which leads to significant overhead. It is much more efficient to have a unified scheme which blends common protocol layer functionalities into a cross-layer module. In this paper, a cross layer protocol (XLP) is introduced, which achieves congestion control, routing, and medium access control in a cross-layer fashion. The design principle of XLP is based on the cross-layer concept of initiative determination, which enables receiver-based contention, initiative-based forwarding, local congestion ...


Evaluating And Regulating Lead In Artificial Turf, Gregory Van Ulirsch, Kevin Gleason, Shawn Gerstenberger, Deaphne B. Moffett, Glenn Pulliam, Tariq Ahmed, Jerald Fagliano 2010 Agency for Toxic Substances and Disease Registry

Evaluating And Regulating Lead In Artificial Turf, Gregory Van Ulirsch, Kevin Gleason, Shawn Gerstenberger, Deaphne B. Moffett, Glenn Pulliam, Tariq Ahmed, Jerald Fagliano

Environmental & Occupational Health Faculty Publications

Background: In 2007, a synthetic turf recreational field in Newark, New Jersey, was closed because lead was found in synthetic turf fibers and in surface dust at concentrations exceeding hazard criteria. Consequently, public health professionals across the country began testing synthetic turf to determine whether it represented a lead hazard. Currently, no standardized methods exist to test for lead in synthetic turf or to assess lead hazards.

Objectives: Our objectives were to increase awareness of potential lead exposure from synthetic turf by presenting data showing elevated lead in fibers and turf-derived dust; identify risk assessment uncertainties; recommend that federal and ...


Boundary Data Maps For Schrödinger Operators On A Compact Interval, Stephen L. Clark, Fritz Gesztesy, M. Mitrea 2010 Missouri University of Science and Technology

Boundary Data Maps For Schrödinger Operators On A Compact Interval, Stephen L. Clark, Fritz Gesztesy, M. Mitrea

Mathematics and Statistics Faculty Research & Creative Works

We provide a systematic study of boundary data maps, that is, 2 x 2 matrix-valued Dirichlet-to-Neumann and more generally, Robin-to-Robin maps, associated with one-dimensional Schrödinger operators on a compact interval [0, R] with separated boundary conditions at 0 and R. Most of our results are formulated in the non-self-adjoint context. Our principal results include explicit representations of these boundary data maps in terms of the resolvent of the underlying Schrödinger operator and the associated boundary trace maps, Krein-type resolvent formulas relating Schrödinger operators corresponding to different (separated) boundary conditions, and a derivation of the Herglotz property of boundary data maps ...


Discovery Of A Young L Dwarf Binary, Sdss224953.47+004404.6ab, Katelyn N. Allers, Michael C. Liu, Trent J. Dupuy, Michael C. Cushing 2010 Bucknell University

Discovery Of A Young L Dwarf Binary, Sdss224953.47+004404.6ab, Katelyn N. Allers, Michael C. Liu, Trent J. Dupuy, Michael C. Cushing

Faculty Journal Articles

No abstract provided.


A Spitzer Search For Planetary-Mass Brown Dwarfs With Circumstellar Disks: Candidate Selection, Paul M. Harvey, Daniel T. Jaffe, Katelyn N. Allers, Michael Liu 2010 Bucknell University

A Spitzer Search For Planetary-Mass Brown Dwarfs With Circumstellar Disks: Candidate Selection, Paul M. Harvey, Daniel T. Jaffe, Katelyn N. Allers, Michael Liu

Faculty Journal Articles

No abstract provided.


The Significance Of Learning Style With Respect To Achievement In First Year Programming Students, Vivian Campbell, Michael Johnstone 2010 Edith Cowan University

The Significance Of Learning Style With Respect To Achievement In First Year Programming Students, Vivian Campbell, Michael Johnstone

ECU Publications Pre. 2011

Study investigates the relationship between the Kolb learning style of first-year programming students and their level of achievement. The method of data collection is described and the process of hypothesis testing is explained. The students in this study were predominately converger and accommodator learning styles. Statistical tests indicated no overall difference between the results of students with different learning styles but a difference was found along Kolb's concrete-abstract axis. A number of possible impacts on teaching are discussed and suggestions made for future research.


Review In Studies In Medieval And Renaissance Teaching Of "Ents, Elves And Eriador: The Environmental Vision Of J.R.R. Tolkien", Alf Siewers 2010 Bucknell University

Review In Studies In Medieval And Renaissance Teaching Of "Ents, Elves And Eriador: The Environmental Vision Of J.R.R. Tolkien", Alf Siewers

Other Faculty Research and Publications

A review of a book-length ecocritical study of J.R.R. Tolkien's fantasy writing.


Linear Stochastic Systems: A White Noise Approach, Daniel Alpay, David Levanony 2010 Chapman University

Linear Stochastic Systems: A White Noise Approach, Daniel Alpay, David Levanony

Mathematics, Physics, and Computer Science Faculty Articles and Research

Using the white noise setting, in particular the Wick product, the Hermite transform, and the Kondratiev space, we present a new approach to study linear stochastic systems, where randomness is also included in the transfer function. We prove BIBO type stability theorems for these systems, both in the discrete and continuous time cases. We also consider the case of dissipative systems for both discrete and continuous time systems. We further study ℓ1-ℓ2 stability in the discrete time case, and L2-L∞ stability in the continuous time case.


Approximate Disassembly, Dhivyakrishnan Radhakrishnan 2010 San Jose State University

Approximate Disassembly, Dhivyakrishnan Radhakrishnan

Master's Projects

For the past two decades, computer viruses have been a constant security threat. A computer virus is a type of malware that may damage computer systems by destroying data, crashing the system, or through other malicious activity. Among the different types of viruses, metamorphic viruses are one of the most difficult to detect since such viruses change their internal structures with each mutation, making signature-based detection infeasible. Many construction kits are available that can be used to easily generate metamorphic strains of any given virus. Previous work has shown that metamorphic viruses are detectable using Hidden Markov Models (HMM). In ...


Detecting Undetectable Computer Viruses, Sujandharan Venkatachalam 2010 San Jose State University

Detecting Undetectable Computer Viruses, Sujandharan Venkatachalam

Master's Projects

Signature-based detection relies on patterns present in viruses and provides a relatively simple and efficient method for detecting known viruses. At present, most anti-virus systems rely primarily on signature detection. Metamorphic viruses are one of the most difficult types of viruses to detect. Such viruses change their internal structure, which provides an effective means of evading signature detection. Previous work has provided a rigorous proof that a fairly simple metamorphic engine can generate viruses that will evade any signature-based detection. In this project, we first implement a metamorphic engine that is provably undetectable—in the sense of signature-based detection. We ...


A Time-Symmetric Formulation Of Quantum Mechanics, Yakir Aharonov, Sandu Popescu, Jeff Tollaksen 2010 Chapman University

A Time-Symmetric Formulation Of Quantum Mechanics, Yakir Aharonov, Sandu Popescu, Jeff Tollaksen

Mathematics, Physics, and Computer Science Faculty Articles and Research

Quantum mechanics allows one to independently select both the initial and final states of a single system. Such pre- and postselection reveals novel effects that challenge our ideas about what time is and how it flows.


Limit On Continuous Neutrino Emission From Neutron Stars, Itzhak Goldman, Shmuel Nussinov 2010 Afeka College of Engineering

Limit On Continuous Neutrino Emission From Neutron Stars, Itzhak Goldman, Shmuel Nussinov

Mathematics, Physics, and Computer Science Faculty Articles and Research

The timing data of the binary pulsar PSR1913+16, are used to establish an upper limit on the rate of continuous neutrino emission from neutron stars. Neutrino emission from each of the neutron stars of the binary system, increases the star binding energy and thus translates to a decrease in their masses. This in turn implies an increase with time of the binary period. Using the pulsar data we obtain an upper limit on the allowed rate of mass reduction: vertical bar M vertical bar < 1.1 x 10(-12) yr(-1) M, where M is the total mass of the binary. This constrains exotic nuclear equations of state that predict continuous neutrino emissions. The limit applies also to other channels of energy loss, e. g. axion emission. Continued timing measurements of additional binary pulsars, should yield a stronger limit in the future.


Effects Of Irrigated Agroecosystems: 2. Quality Of Soil Water And Groundwater In The Southern High Plains, Texas, B. R. Scanlon, J. B. Gates, R. C. Reedy, W. A. Jackson, J. P. Bordovsky 2010 University of Texas at Austin

Effects Of Irrigated Agroecosystems: 2. Quality Of Soil Water And Groundwater In The Southern High Plains, Texas, B. R. Scanlon, J. B. Gates, R. C. Reedy, W. A. Jackson, J. P. Bordovsky

Papers in the Earth and Atmospheric Sciences

Trade‐offs between water‐resource depletion and salinization need to be understood when promoting water‐conservative irrigation practices. This companion paper assesses impacts of groundwater‐fed irrigation on soil water and groundwater quality using data from the southern High Plains (SHP). Unsaturated zone soil samples from 13 boreholes beneath irrigated agroecosystems were analyzed for water‐extractable anions. Salt accumulation in soils varies with irrigation water quality, which ranges from low salinity in the north (median Cl: 21 mg/L) to higher salinity in the south (median Cl: 180 mg/L). Large Cl bulges under irrigated agroecosystems in the south are ...


Influence Of The Arctic Oscillation On Central United States Summer Rainfall, Qi Hu, Song Feng 2010 University of Nebraska-Lincoln

Influence Of The Arctic Oscillation On Central United States Summer Rainfall, Qi Hu, Song Feng

Papers in the Earth and Atmospheric Sciences

Effects of the Arctic oscillation (AO) on summer rainfall variability in the central United States are examined in order to improve understanding and prediction of the interannual variation in the summer rainfall. Major results show persistent AO effects that resulted in less summer rainfall in the central United States during the positive phase of the AO and more rainfall during the negative AO phase. These effects are most prominent at the interannual time scale. The key physical processes connecting the AO with the rainfall variations are shown in changes in latitudinal location of the midlatitude upper tropospheric westerly jet over ...


A Modelling Approach To Evaluate Potential Management Actions Designed To Increase Growth Of White Perch In A High-Density Population, Christopher J. Chizinski, Kevin L. Pope, G.R. Wilde 2010 Texas Tech University

A Modelling Approach To Evaluate Potential Management Actions Designed To Increase Growth Of White Perch In A High-Density Population, Christopher J. Chizinski, Kevin L. Pope, G.R. Wilde

Nebraska Cooperative Fish & Wildlife Research Unit -- Staff Publications

A deterministic, age-structured population model was developed to simulate potential management scenarios designed to increase growth of individuals (quantified by maximum length) in a hypothetical population of white perch, Morone americana (Gmelin). Four scenarios were developed that included non-selective mortality of adult white perch, increased mortality of age groups most influential on population growth, increased age-0 mortality and inhibiting recruitment after spawning. The greatest increase in maximum length occurred with nonselective adult mortality when population biomass was reduced by 97%; lesser increases in maximum length were achieved with the other management scenarios. Populations returned to their original state after control ...


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