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2017

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Full-Text Articles in Physical Sciences and Mathematics

Analiza E Performancës Së Kriptosistemeve Des, Aes Dhe Blowfish, Dion Klajiqi Oct 2017

Analiza E Performancës Së Kriptosistemeve Des, Aes Dhe Blowfish, Dion Klajiqi

Theses and Dissertations

Kriptografia është shkenca e cila merret me metodat dhe teoritë e enkriptimit dhe dekriptimit. Influenca e saj është e padiskutueshme në teknologjinë informative dhe gjen zbatim në shumë fusha ku siguria ka një prioritet të veçantë. Kriptografia ndahet në dy grupe: kriptosistemet me çelës simetrik dhe kriptosistemet me çelës publik. Nga këto dy grupe është bërë shpjegimi dhe analiza e kriptosistemeve me celës simetrik duke përzgjedhur kriptosistemet DES, AES dhe BLOWFISH. Analiza është performuar duke përdorur fajlla me tekst të madhësive të ndryshme dhe duke përdorur celësin specifik për kriptosistemin të gjeneruar random është realizuar enkriptimi dhe dekriptimi i fajllave …


Zhvillimi I Një Aplikacioni Mobil Për Sistemin Operativ Android – “Restaurant Kroni”, Shpat Braina Oct 2017

Zhvillimi I Një Aplikacioni Mobil Për Sistemin Operativ Android – “Restaurant Kroni”, Shpat Braina

Theses and Dissertations

Fokusi kryesor i kësaj teme është i bazuar në hartimin dhe zhvillimin e një aplikacioni për menaxhimin e restauranteve dhe mundësitë për zhvillim që ofron sistemi operativ Android. Gjatë punimit të kësaj teme krahas shpjegimit se si zhvillohet një aplikacioni mobil për pajisjet që përdorin sistemin operativ Android janë marrë edhe kërkesa specifike rreth qëllimit të aplikacionit i cili është informimi i klientëve të restaurantit në lidhje me informatat bazë të tij.

Në këtë temë kemi përshkruar dhe realizuar një aplikacion për “Restaurant Kroni” si native Android aplikacion, i cili ka përmbajtje dinamike ku për të realizuar këtë funksion të …


Siguria Në Teknologjitë Cloud, Kushtrim Kadriu Oct 2017

Siguria Në Teknologjitë Cloud, Kushtrim Kadriu

Theses and Dissertations

Teknologjia informative është term me të cilin përfshihen të gjitha teknologjitë që përdoren për krijimin, përpunimin, ruajtjen, transmetimin, këmbimin dhe përdorimin e informacioneve në të gjitha format e saj, siç janë: shënimet e biznesit, konverzacionet gojore, fotografitë, pikturat, prezantimet video dhe format tjera, duke përfshirë edhe ato ende të pa krijuara. Kështu i definuar, ky term më së miri integron elektronikën, telekomunikacionin (telecommunications), informatikën (informatics), Internetin dhe mediumet (media).

Në shekullin në të cilin po jetojmë një nga risitë më të mëdha është e ashtuquajtura “Cloud”. Ky kërkim do të shtjellojë teknologjitë Cloud dhe përdorimin e tyre nga personat privatë, …


Vulnerabiliteti I Fjalëkalimeve Me Sekuenca Përseritëse Numerike Në Protokolin Wpa2, Genc Kelmendi Oct 2017

Vulnerabiliteti I Fjalëkalimeve Me Sekuenca Përseritëse Numerike Në Protokolin Wpa2, Genc Kelmendi

Theses and Dissertations

Protokolet që sigurojnë rrjetin wireless WPA2/WPA kanë dëshmuar siguri të lartë në dallim nga paraardhësi i tyre WEP. Megjithëkëtë, faktori njeri rrezikon soliditetin e kriptografisë, duke implementuar fjalëkalime që përmbajnë struktura numerike të parashikueshme programatikisht. Kjo praktikë rrezikon posaçërishtë sigurinë e protokolit WPA sepse handshake-u WPA i ruajtur lokalisht mund të sulmohet për një numër të pakufizuar herësh duke shfrytëzuar sulmet brute-force. Metodat e prezantuara janë efikase të dekriptojnë fjalëkalimet me sekuenca përsëritëse numerike brenda sekondave duke shfrytëzuar vetëm fuqi procesorike ordinere. Prevalenca e kësaj praktike vulnerabile në regjionin e Prishtinës (Kosovë) është paraqitur të jetë 15.7% në 89 wirelessa …


An Enhanced Operational Definition Of Dielectric Breakdown For Dc Voltage Step-Up Tests, Allen Andersen, Jr Dennison Oct 2017

An Enhanced Operational Definition Of Dielectric Breakdown For Dc Voltage Step-Up Tests, Allen Andersen, Jr Dennison

Journal Articles

The imprecise definition of breakdown in the ASTM D3755-14 standard can misidentify breakdown. If the recommended test circuit current sensing element threshold is set too high, breakdown may occur undetected. Conversely, false positives may result from designating a low current threshold. An operational definition of breakdown much less sensitive to these pitfalls is outlined herein. This enhanced definition of breakdown is based on the average rate of change of the leakage current with increasing voltage, rather than a simple current threshold, avoiding ambiguous association with anomalies in current traces. For tests that continuously monitor leakage current, breakdown can be detected …


Highly Accelerated Test Method For Characterizing Likelihood Of Breakdown In Hvdc Dielectric Materials, Allen Andersen, Jr Dennison Oct 2017

Highly Accelerated Test Method For Characterizing Likelihood Of Breakdown In Hvdc Dielectric Materials, Allen Andersen, Jr Dennison

Journal Articles

Increasing application and development of HVDC technologies emphasizes the need for improved characterization of candidate insulating materials. Accurately predicting the lifetime to breakdown of dielectric materials by means of accelerated voltage step-up to breakdown tests can be prohibitively time consuming. Step-up to breakdown tests with sufficiently slow voltage ramp rates that continuously monitor leakage current have detected a distribution of DC partial discharge (DCPD) events occurring prior to breakdown, which increase with increasing field. These DCPD distributions are shown to correlate strongly with the likelihood of breakdown for four common polymers. Given that hundreds of DCPD events are typically observed …


Do Advisors Perceive Climate Change As An Agricultural Risk? An In-Depth Examination Of Midwestern U.S. Ag Advisors’ Views On Drought, Climate Change, And Risk Management, Sarah P. Church, Michael Dunn, Nicholas Babin, Amber Saylor Mase, Tonya Haigh, Linda Stalker Prokopy Oct 2017

Do Advisors Perceive Climate Change As An Agricultural Risk? An In-Depth Examination Of Midwestern U.S. Ag Advisors’ Views On Drought, Climate Change, And Risk Management, Sarah P. Church, Michael Dunn, Nicholas Babin, Amber Saylor Mase, Tonya Haigh, Linda Stalker Prokopy

Drought Mitigation Center: Faculty Publications

Through the lens of the Health Belief Model and Protection Motivation Theory, we analyzed interviews of 36 agricultural advisors in Indiana and Nebraska to understand their appraisals of climate change risk, related decision making processes and subsequent risk management advice to producers. Most advisors interviewed accept that weather events are a risk for US Midwestern agriculture; however, they are more concerned about tangible threats such as crop prices. There is not much concern about climate change among agricultural advisors. Management practices that could help producers adapt to climate change were more likely to be recommended by conservation and Extension advisors, …


Reactions To Imagery Generated Using Computational Aesthetic Measures, Prasad Gade, Mary Galvin, James O'Sullivan, Paul Walsh, Órla Murphy Oct 2017

Reactions To Imagery Generated Using Computational Aesthetic Measures, Prasad Gade, Mary Galvin, James O'Sullivan, Paul Walsh, Órla Murphy

Department of Computer Science Publications

This article examines whether textural generation system imagery evolved with computational aesthetic support can be judged as having aesthetic attributes, both when knowing and not knowing its true origin. Such a generation, depicting a digital landscape, is offered to two groups of participants to appraise. It is hypothesized that there will be no statistically significant difference between the groups on their appraisal of the image. Results from statistical analysis prove to be consistent with this hypothesis. A minority of participants, however, do exhibit significant differences in their perception of the image based on its means of production. This article explores …


Life In Hampton Roads: Sea Level Rise And Flooding, Public Affairs & News Bureau, Old Dominion University Oct 2017

Life In Hampton Roads: Sea Level Rise And Flooding, Public Affairs & News Bureau, Old Dominion University

News Items

No abstract provided.


Odu Scientists Address Antarctic Ice Melt Affecting Sea Levels, Miasia Osbey Oct 2017

Odu Scientists Address Antarctic Ice Melt Affecting Sea Levels, Miasia Osbey

News Items

No abstract provided.


Maneuverable Applications: Advancing Distributed Computing, William Clay Moody, Amy W. Apon Oct 2017

Maneuverable Applications: Advancing Distributed Computing, William Clay Moody, Amy W. Apon

Publications

Extending the military principle of maneuver into the war-fighting domain of cyberspace, academic and military researchers have produced many theoretical and strategic works, though few have focused on researching the applications and systems that apply this principle. We present a survey of our research in developing new architectures for the enhancement of parallel and distributed applica-tions. Specifically, we discuss our work in applying the military concept of maneuver in the cyberspace domain by creating a set of applications and systems called “ma-neuverable applications.” Our research investigates resource provisioning, application optimization, and cybersecurity enhancement through the modification, relocation, addition or removal …


Gw170814: A Three-Detector Observation Of Gravitational Waves From A Binary Black Hole Coalescence, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website. Oct 2017

Gw170814: A Three-Detector Observation Of Gravitational Waves From A Binary Black Hole Coalescence, Benjamin P. Abbott, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

On August 14, 2017 at 10 30:43 UTC, the Advanced Virgo detector and the two Advanced LIGO detectors coherently observed a transient gravitational-wave signal produced by the coalescence of two stellar mass black holes, with a false-alarm rate of ≲1 in 27 000 years. The signal was observed with a three-detector network matched-filter signal-to-noise ratio of 18. The inferred masses of the initial black holes are 30.5-3.0+5.7M⊙ and 25.3-4.2+2.8M⊙ (at the 90% credible level). The luminosity distance of the source is 540-210+130 Mpc, corresponding to a redshift of z=0.11-0.04+0.03 …


Almost-Bps Solutions In Multi-Center Taub-Nut, C. Rugina, A. Ludu Oct 2017

Almost-Bps Solutions In Multi-Center Taub-Nut, C. Rugina, A. Ludu

Publications

Microstates of multiple collinear black holes embedded in a non-collinear two-center Taub-NUT spacetime are sought in 4 dimensions. A set of coupled partial differential equations are obtained and solved for almost-BPS states, where some supersymmetry is preserved in the context of N = 2 supergravity in 4 dimensions. The regularity of solutions is carefully considered, and we ensure that no CTC (closed time-like curves) are present. The larger framework is that of 11-dimensional N = 2 supergravity, and the current theory is obtained by compactifying it down to 4 dimensions. This work is a generalization (to three non-collinear centers) of …


Phase Stability, Ordering Tendencies, And Magnetism In Single-Phase Fcc Au-Fe Nanoalloys, I. A. Zhuravlev, S. V. Barabash, J. M. An, K. D. Belashchenko Oct 2017

Phase Stability, Ordering Tendencies, And Magnetism In Single-Phase Fcc Au-Fe Nanoalloys, I. A. Zhuravlev, S. V. Barabash, J. M. An, K. D. Belashchenko

Department of Physics and Astronomy: Faculty Publications

Bulk Au-Fe alloys separate into Au-based fcc and Fe-based bcc phases, but L10 and L12 orderings were reported in single-phase Au-Fe nanoparticles. Motivated by these observations, we study the structural and ordering energetics in this alloy by combining density functional theory (DFT) calculations with effective Hamiltonian techniques: a cluster expansion with structural filters, and the configuration-dependent lattice deformation model. The phase separation tendency in Au-Fe persists even if the fcc-bcc decomposition is suppressed. The relative stability of disordered bcc and fcc phases observed in nanoparticles is reproduced, but the fully ordered L10 AuFe, L12 Au3Fe, and L12 AuFe3 structures are …


Phys 201: Modern Topics In Physics And Astronomy, Ken Bloom Oct 2017

Phys 201: Modern Topics In Physics And Astronomy, Ken Bloom

Department of Physics and Astronomy: Syllabi

Syllabus for PHYS 201: Modern Topics in Physics and Astronomy syllabus for Fall 2017.


Quantifying Certainty: The P-Value, Dominic Klyve Oct 2017

Quantifying Certainty: The P-Value, Dominic Klyve

Statistics and Probability

No abstract provided.


Gaussian Guesswork: Infinite Sequences And The Arithmetic-Geometric Mean, Janet Heine Barnett Oct 2017

Gaussian Guesswork: Infinite Sequences And The Arithmetic-Geometric Mean, Janet Heine Barnett

Calculus

No abstract provided.


Word Sense Determination From Wikipedia Data Using Neural Networks, Qiao Liu Oct 2017

Word Sense Determination From Wikipedia Data Using Neural Networks, Qiao Liu

Master's Projects

Many words have multiple meanings. For example, “plant” can mean a type of living organism or a factory. Being able to determine the sense of such words is very useful in natural language processing tasks, such as speech synthesis, question answering, and machine translation. For the project described in this report, we used a modular model to classify the sense of words to be disambiguated. This model consisted of two parts: The first part was a neural-network-based language model to compute continuous vector representations of words from data sets created from Wikipedia pages. The second part classified the meaning of …


Healthcare Outcomes And Resource Utilization Associated With Neonatal Hypoglycemia: Analysis Of Data From The Hcup Kid’S Inpatient Database, Brook T. Alemu Oct 2017

Healthcare Outcomes And Resource Utilization Associated With Neonatal Hypoglycemia: Analysis Of Data From The Hcup Kid’S Inpatient Database, Brook T. Alemu

Health Services Research Dissertations

Neonatal hypoglycemia is the most common metabolic abnormality in infants and is associated with neurological damage and death. The risk of developing hypoglycemia among infants born from diabetic mothers is even higher. Although much work has been performed addressing issues for treatment and care, research related to neonatal hypoglycemia has been focused on the clinical or individual level risk factors. Contextual risk factors such as hospital characteristics, neighborhood economic status, and regional variations were not considered in earlier studies. Additionally, although healthcare resources utilization of hypoglycemia has been adequately addressed in the adult population, this topic has not been studied …


Efficient And Robust Emergence Of Norms Through Heuristic Collective Learning, Jianye Hao, Jun Sun, Guangyong Chen, Zan Wang, Chao Yu, Zhong Ming Oct 2017

Efficient And Robust Emergence Of Norms Through Heuristic Collective Learning, Jianye Hao, Jun Sun, Guangyong Chen, Zan Wang, Chao Yu, Zhong Ming

Research Collection School Of Computing and Information Systems

In multiagent systems, social norms serves as an important technique in regulating agents’ behaviors to ensure effective coordination among agents without a centralized controlling mechanism. In such a distributed environment, it is important to investigate how a desirable social norm can be synthesized in a bottom-up manner among agents through repeated local interactions and learning techniques. In this article, we propose two novel learning strategies under the collective learning framework, collective learning EV-l and collective learning EV-g, to efficiently facilitate the emergence of social norms. Extensive simulations results show that both learning strategies can support the emergence of desirable …


Marine Reserves Promote Coral Reef Resilience By Mitigating Human Impacts Through The Restoration Of Parrotfish Populations, Increasing Their Reproductive Output And Seeding Neighboring Overfished Reefs, Brian L. Stockwell Oct 2017

Marine Reserves Promote Coral Reef Resilience By Mitigating Human Impacts Through The Restoration Of Parrotfish Populations, Increasing Their Reproductive Output And Seeding Neighboring Overfished Reefs, Brian L. Stockwell

Biological Sciences Theses & Dissertations

Coral reefs are some of the most productive ecosystems on the planet, providing fisheries resources for over a billion people with billions of dollars in revenue from tourism for developing nations. Coral reefs are under threat from overfishing and water pollution, resulting in less productive algae dominated reefs. Marine reserves are widely expected to promote the resilience of reefs by protecting and increasing the abundance of herbivorous fishes that can graze on algae, therefore directly or indirectly preventing coral to algal phase shifts. However, the ability of marine reserves to mitigate human impacts, restore herbivorous fish populations and seed nearby …


Precipitation And Sea Level Rise Impacts On Groundwater Levels In Virginia Beach, Virginia, Brett A. Buzzanga Oct 2017

Precipitation And Sea Level Rise Impacts On Groundwater Levels In Virginia Beach, Virginia, Brett A. Buzzanga

OES Theses and Dissertations

Global sea level rise (SLR) is one of the most immediate impacts of climate change, and poses a significant threat to low-lying coastal communities worldwide. The metropolitan region of Hampton Roads in Southeastern Virginia is one such community, and one where knowledge surrounding SLR is rapidly accumulating. However, most of the research is focused exclusively on surface water processes despite the presence of a shallow groundwater table closely connected to them. SLR will continue to cause the groundwater table to increase in tidally influenced areas of Hampton Roads, and thereby decrease storage capacity of the unsaturated zone.

This study investigates …


Life History And Management Methods For Blueline Tilefish (Caulolatilus Microps) From The United States Mid-Atlantic Region, Michael A. Schmidtke Oct 2017

Life History And Management Methods For Blueline Tilefish (Caulolatilus Microps) From The United States Mid-Atlantic Region, Michael A. Schmidtke

OES Theses and Dissertations

Blueline tilefish (Caulolatilus microps) have recently undergone an increase in landings from waters off the US Mid-Atlantic region (Virginia-Massachusetts). Currently, life history characteristics of blueline tilefish in this area are undescribed. Additionally, appropriate indices of population abundance are not available for this region, necessitating the use of data-limited management methods to set restrictions for harvest of blueline tilefish in this area. This dissertation describes growth and reproductive characteristics of blueline tilefish caught off the coast of Virginia and explores improvements of data-limited management methods that have been applied to blueline tilefish in the US Mid-Atlantic. Blueline tilefish from …


Modeling Energy Consumption Of High-Performance Applications On Heterogeneous Computing Platforms, Gary D. Lawson Jr. Oct 2017

Modeling Energy Consumption Of High-Performance Applications On Heterogeneous Computing Platforms, Gary D. Lawson Jr.

Computational Modeling & Simulation Engineering Theses & Dissertations

Achieving Exascale computing is one of the current leading challenges in High Performance Computing (HPC). Obtaining this next level of performance will allow more complex simulations to be run on larger datasets and offer researchers better tools for data processing and analysis. In the dawn of Big Data, the need for supercomputers will only increase. However, these systems are costly to maintain because power is expensive. Thus, a better understanding of power and energy consumption is required such that future hardware can benefit.

Available power models accurately capture the relationship to the number of cores and clock-rate, however the relationship …


Sensys: A Smartphone-Based Framework For Its Applications, Abdulla Ahmed Alasaadi Oct 2017

Sensys: A Smartphone-Based Framework For Its Applications, Abdulla Ahmed Alasaadi

Computer Science Theses & Dissertations

Intelligent transportation systems (ITS) use different methods to collect and process traffic data. Conventional techniques suffer from different challenges, like the high installation and maintenance cost, connectivity and communication problems, and the limited set of data. The recent massive spread of smartphones among drivers encouraged the ITS community to use them to solve ITS challenges.

Using smartphones in ITS is gaining an increasing interest among researchers and developers. Typically, the set of sensors that comes with smartphones is utilized to develop tools and services in order to enhance safety and driving experience. GPS, cameras, Bluetooth, inertial sensors and other embedded …


Selenium Distribution And Cycling In The Eastern Equatorial Pacific Ocean, Zoe Wambaugh Oct 2017

Selenium Distribution And Cycling In The Eastern Equatorial Pacific Ocean, Zoe Wambaugh

OES Theses and Dissertations

Oxygen minimum zones in oceanic waters have become increasingly important to the marine environment and society. Low oxygen waters affect not only the distribution and abundance of marine organisms, but also impact the solubility and transport of trace elements that are of biological importance, with the chemical speciation and solubility depending on the actual redox poise of the waters. One redox sensitive trace element of interest is selenium, which can be both toxic and essential for organisms, depending on its chemical speciation. In 2013, the US GEOTRACES program completed the GP16 transect from Peru to Tahiti, going through the oxygen …


Computational Methods For Nonlinear Systems Analysis With Applications In Mathematics And Engineering, Geoffrey Kenneth Rose Oct 2017

Computational Methods For Nonlinear Systems Analysis With Applications In Mathematics And Engineering, Geoffrey Kenneth Rose

Mechanical & Aerospace Engineering Theses & Dissertations

An investigation into current methods and new approaches for solving systems of nonlinear equations was performed. Nontraditional methods for implementing arc-length type solvers were developed in search of a more robust capability for solving general systems of nonlinear algebraic equations. Processes for construction of parameterized curves representing the many possible solutions to systems of equations versus finding single or point solutions were established. A procedure based on these methods was then developed to identify static equilibrium states for solutions to multi-body-dynamic systems. This methodology provided for a pictorial of the overall solution to a given system, which demonstrated the possibility …


Computational Modeling For Abnormal Brain Tissue Segmentation, Brain Tumor Tracking, And Grading, Syed Mohammad Shamin Reza Oct 2017

Computational Modeling For Abnormal Brain Tissue Segmentation, Brain Tumor Tracking, And Grading, Syed Mohammad Shamin Reza

Electrical & Computer Engineering Theses & Dissertations

This dissertation proposes novel texture feature-based computational models for quantitative analysis of abnormal tissues in two neurological disorders: brain tumor and stroke. Brain tumors are the cells with uncontrolled growth in the brain tissues and one of the major causes of death due to cancer. On the other hand, brain strokes occur due to the sudden interruption of the blood supply which damages the normal brain tissues and frequently causes death or persistent disability. Clinical management of these brain tumors and stroke lesions critically depends on robust quantitative analysis using different imaging modalities including Magnetic Resonance (MR) and Digital Pathology …


Population Structure Of Lethrinus Lentjan (Lethrinidae, Percoidei) Across The South China Sea And The Philippines Is Detected With Lane-Affected Radseq Data, Ellen E. Biesack Oct 2017

Population Structure Of Lethrinus Lentjan (Lethrinidae, Percoidei) Across The South China Sea And The Philippines Is Detected With Lane-Affected Radseq Data, Ellen E. Biesack

Biological Sciences Theses & Dissertations

Southeast Asia includes the Coral Triangle, a marine biodiversity hotspot that supports important fishery resources experiencing varied threats. Patterns of speciation and population structure in the Coral Triangle have been examined to test hypotheses relating to the historical geologic processes that may have influenced this biodiversity phenomenon. This study investigates the genetic population structure of the Pink-ear Emperor Snapper, Lethrinus lentjan (Lacepède, 1802), across the Philippines and the South China Sea. The species is fished throughout the Coral Triangle by subsistence and commercial fishers and their landings have been in decline for several years, which could be indicative of depleted …


Quantifying Pollutant Removal Rates Of Bioretention Basins As A Stormwater Best Management Practice, Evan Nathanial Waagen Oct 2017

Quantifying Pollutant Removal Rates Of Bioretention Basins As A Stormwater Best Management Practice, Evan Nathanial Waagen

Civil & Environmental Engineering Theses & Dissertations

Water pollution is an ongoing problem that can be attributed to human activities. As world population increases and countries become more developed, this problem intensifies. Fortunately, the causes and solutions of water pollution are documented and have been implemented with various levels of success. These solutions, or Best Management Practices (BMPs), vary in type and function and remove pollutants from runoff prior to it reaching rivers, lakes, and other bodies of water. This study investigates bioretention basins, a specific group of BMPs, and presents analysis and prediction of their performance, of which our knowledge is incomplete in the existing literature. …