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2015

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Articles 9331 - 9360 of 9578

Full-Text Articles in Physical Sciences and Mathematics

E-Mail Authorship Attribution Using Customized Associative Classification, Michael R. Schmid, Farkhund Iqbal, Benjamin C.M. Fung Jan 2015

E-Mail Authorship Attribution Using Customized Associative Classification, Michael R. Schmid, Farkhund Iqbal, Benjamin C.M. Fung

All Works

E-mail communication is often abused for conducting social engineering attacks including spamming, phishing, identity theft and for distributing malware. This is largely attributed to the problem of anonymity inherent in the standard electronic mail protocol. In the literature, authorship attribution is studied as a text categorization problem where the writing styles of individuals are modeled based on their previously written sample documents. The developed model is employed to identify the most plausible writer of the text. Unfortunately, most existing studies focus solely on improving predictive accuracy and not on the inherent value of the evidence collected. In this study, we …


Enhancing Social Science Research In The Uae: An Open Source Software Solution University Of Sharjah (Uos) Case Study, Manar Abu Talib, Muhammed Abuodeh, Adhraa Almansoori, Arwa Alnauimi Jan 2015

Enhancing Social Science Research In The Uae: An Open Source Software Solution University Of Sharjah (Uos) Case Study, Manar Abu Talib, Muhammed Abuodeh, Adhraa Almansoori, Arwa Alnauimi

All Works

© 2015 The Manar Abu Talib, Muhammed AbuOdeh, Adhraa Almansoori and Arwa AlNauimi. Researchers, practitioners and social scientists all agree on the enormous importance of social science research in advancing human knowledge and informing public policy makers. The National Research Foundation, along with other organizations in the UAE, is leading the initiative to integrate the efforts of social research institutions in order to support the decision making process in the UAE. As indicated by a number of social researchers during the last forum held on May 29-30, 2012, at the Emirates Center for Strategic Studies and Research, Abu Dhabi, UAE, …


Factors Influencing Digital Forensic Investigations: Empirical Evaluation Of 12 Years Of Dubai Police Cases, Ibtesam Alawadhi, Janet Read, Andrew Marrington, Virginia Franqueira Jan 2015

Factors Influencing Digital Forensic Investigations: Empirical Evaluation Of 12 Years Of Dubai Police Cases, Ibtesam Alawadhi, Janet Read, Andrew Marrington, Virginia Franqueira

All Works

In Digital Forensics, the number of person-hours spent on investigation is a key factor which needs to be kept to a minimum whilst also paying close attention to the authenticity of the evidence. The literature describes challenges behind increasing person-hours and identifies several factors which contribute to this phenomenon. This paper reviews these factors and demonstrates that they do not wholly account for increases in investigation time. Using real case records from the Dubai Police, an extensive study explains the contribution of other factors to the increase in person-hours. We conclude this work by emphasizing on several factors affecting the …


Monolithic Optofluidic Ring Resonator Lasers Created By Femtosecond Laser Nanofabrication, Hengky Chandrahalim, Qiushu Chen, Ali A. Said, Mark Dugan, Xudong Fan Jan 2015

Monolithic Optofluidic Ring Resonator Lasers Created By Femtosecond Laser Nanofabrication, Hengky Chandrahalim, Qiushu Chen, Ali A. Said, Mark Dugan, Xudong Fan

Faculty Publications

We designed, fabricated, and characterized a monolithically integrated optofluidic ring resonator laser that is mechanically, thermally, and chemically robust. The entire device, including the ring resonator channel and sample delivery microfluidics, was created in a block of fused-silica glass using a 3-dimensional femtosecond laser writing process. The gain medium, composed of Rhodamine 6G (R6G) dissolved in quinoline, was flowed through the ring resonator. Lasing was achieved at a pump threshold of approximately 15 μJ/mm2. Detailed analysis shows that the Q-factor of the optofluidic ring resonator is 3.3 × 104, which is limited by both solvent …


Network And Device Forensic Analysis Of Android Social-Messaging Applications, Daniel Walnycky, Ibrahim Baggili, Andrew Marrington, Jason Moore, Frank Breitinger Jan 2015

Network And Device Forensic Analysis Of Android Social-Messaging Applications, Daniel Walnycky, Ibrahim Baggili, Andrew Marrington, Jason Moore, Frank Breitinger

All Works

In this research we forensically acquire and analyze the device-stored data and network traffic of 20 popular instant messaging applications for Android. We were able to reconstruct some or the entire message content from 16 of the 20 applications tested, which reflects poorly on the security and privacy measures employed by these applications but may be construed positively for evidence collection purposes by digital forensic practitioners. This work shows which features of these instant messaging applications leave evidentiary traces allowing for suspect data to be reconstructed or partially reconstructed, and whether network forensics or device forensics permits the reconstruction of …


Facies, Architecture, And Sequence Stratigraphy Of The Devonian-Mississippian Sappington Formation, Bridger Range, Montana, Anna S. Phelps Jan 2015

Facies, Architecture, And Sequence Stratigraphy Of The Devonian-Mississippian Sappington Formation, Bridger Range, Montana, Anna S. Phelps

Graduate Student Theses, Dissertations, & Professional Papers

The Late Devonian-Early Mississippian Sappington Formation in Montana is a marine unit comprised of lower and upper organic-rich shale members and a middle calcareous siltstone member. The Sappington Formation was deposited during a period of complex paleogeography in Montana, characterized by deposition in sub-basins and onlap onto structural highs, and eustatically- and tectonically-driven transgressive-regressive cycles. Detailed outcrop analysis was conducted on the Sappington Formation across the Bridger Range in southwestern Montana to better understand the Sappington Formation depositional system and changing regional paleogeography. The Sappington Formation is further interpreted in a stratigraphic architectural framework to improve the ability to predict …


Sediment Routing Through Channel Confluences: Particle Tracing In A Gravel-Bed River Headwaters, Kurt Imhoff Jan 2015

Sediment Routing Through Channel Confluences: Particle Tracing In A Gravel-Bed River Headwaters, Kurt Imhoff

Graduate Student Theses, Dissertations, & Professional Papers

Sediment routing in gravel-bed rivers refers to the intermittent transport and storage of bedload particles, where short-duration steps are separated by periods of inactivity. Channel morphology governs sediment routing, but morphologic effects on routing in headwater systems are not well understood compared to lowland systems. RFID tracers are a valuable tool that can be employed to characterize routing processes in headwater channels through individual particle tracking. I present research on coarse sediment transport and dispersion through confluences using sediment tracers in the East Fork Bitterroot River basin, MT. I investigate the following questions: (1) How do sediment routing patterns through …


A Gis Assessment Of Ecoregion Representation In Chile's Existing And Proposed Integrated Network Of Protected Areas, Jessica Schutz Jan 2015

A Gis Assessment Of Ecoregion Representation In Chile's Existing And Proposed Integrated Network Of Protected Areas, Jessica Schutz

Graduate Student Theses, Dissertations, & Professional Papers

Chile's state designated protected areas are reported to show representation bias and to be unable to meet conservation goals. Private protected areas are considered an important tool to resolve these issues, which has led to support for increasing the role of private protected areas in Chile and creating an integrated public-private protected area network. But the validity of the capacity of private protected areas to fix Chile's state protected area network bias, and the advantage of creating an integrated protected area network, have not been assessed. This study uses the most recent data on Chile's state, private, and international protected …


A Service Oriented Broker-Based Approach For Dynamic Resource Discovery In Virtual Networks, Sleiman Rabah, May El Barachi, Nadjia Kara, Rachida Dssouli, Joey Paquet Jan 2015

A Service Oriented Broker-Based Approach For Dynamic Resource Discovery In Virtual Networks, Sleiman Rabah, May El Barachi, Nadjia Kara, Rachida Dssouli, Joey Paquet

All Works

© 2015, Rabah et al.; licensee Springer. In the past few years, the concept of network virtualization has received significant attention from industry and research fora. This concept applies virtualization to networking infrastructures by enabling the dynamic creation of several co-existing logical network instances (or virtual networks) over a shared physical network infrastructure (or substrate network). Due to the potential it offers in terms of diversifying existing networks and ensuring the co-existence of heterogeneous network architectures on top of shared substrates, network virtualization is often considered as an enabler of a polymorphic Internet and a cornerstone of the future Internet …


Effects Of Prescribed Fire On Upland Plant Biodiversity And Abundance In Northeast Florida, Peter D. Maholland Jan 2015

Effects Of Prescribed Fire On Upland Plant Biodiversity And Abundance In Northeast Florida, Peter D. Maholland

UNF Graduate Theses and Dissertations

Terrestrial ecosystems in the southeastern United States have evolved with fire as a common disturbance and as a result many natural communities require the presence of fire to persist over time. Human development precludes natural fires from occurring within these communities; however, prescribed fire is considered to be a critical tool in the effort to restore fire-dependent ecosystems after decades of fire exclusion. Direct effects of fire on individual floral and faunal species as well as benefits to biodiversity at the landscape (gamma diversity) level have largely been supported in previous research. However, information on the effects of natural and …


Time Series Similarity Search In Distributed Key-Value Data Stores Using R-Trees, Aleksey Charapko Jan 2015

Time Series Similarity Search In Distributed Key-Value Data Stores Using R-Trees, Aleksey Charapko

UNF Graduate Theses and Dissertations

Time series data are sequences of data points collected at certain time intervals. The advance in mobile and sensor technologies has led to rapid growth in the available amount of time series data. The ability to search large time series data sets can be extremely useful in many applications. In healthcare, a system monitoring vital signals can perform a search against the past data and identify possible health threatening conditions. In engineering, a system can analyze performances of complicated equipment and identify possible failure situations or needs of maintenance based on historical data.

Existing search methods for time series data …


Sorting By Block Moves, Jici Huang Jan 2015

Sorting By Block Moves, Jici Huang

UNF Graduate Theses and Dissertations

The research in this thesis is focused on the problem of Block Sorting, which has applications in Computational Biology and in Optical Character Recognition (OCR). A block in a permutation is a maximal sequence of consecutive elements that are also consecutive in the identity permutation. BLOCK SORTING is the process of transforming an arbitrary permutation to the identity permutation through a sequence of block moves. Given an arbitrary permutation π and an integer m, the Block Sorting Problem, or the problem of deciding whether the transformation can be accomplished in at most m block moves has been shown to be …


Characterization Of A Biosynthetic Pathway Yielding Anticancer Natural Products From A Marine Bacterium, Elle D. James Jan 2015

Characterization Of A Biosynthetic Pathway Yielding Anticancer Natural Products From A Marine Bacterium, Elle D. James

UNF Graduate Theses and Dissertations

Natural products are bioactive secondary metabolites produced by living organisms and are prevalently utilized as pharmaceutical drugs. Marine adapted organisms are a promising source of new natural products possessing unique chemical structures and biological activities. By studying the biosynthetic pathways employed by living organisms to produce natural products, insights into new strategies to generate molecules to combat disease and overcome drug resistance may be gained. This thesis study aimed to uncover the biosynthetic pathway employed by a marine actinomycete, Nocardiopsis sp. CMB-M0232, to catalyze the assembly of the nocardioazines. These molecules are a group of 2,5-diketopiperazine natural products that feature …


A Comparison Of Cloud Computing Database Security Algorithms, Joseph A. Hoeppner Jan 2015

A Comparison Of Cloud Computing Database Security Algorithms, Joseph A. Hoeppner

UNF Graduate Theses and Dissertations

The cloud database is a relatively new type of distributed database that allows companies and individuals to purchase computing time and memory from a vendor. This allows a user to only pay for the resources they use, which saves them both time and money. While the cloud in general can solve problems that have previously been too costly or time-intensive, it also opens the door to new security problems because of its distributed nature. Several approaches have been proposed to increase the security of cloud databases, though each seems to fall short in one area or another.

This thesis presents …


Integrating Security Into The Undergraduate Software Engineering Curriculum, Robert Evans Jan 2015

Integrating Security Into The Undergraduate Software Engineering Curriculum, Robert Evans

UNF Graduate Theses and Dissertations

This research included a thorough examination of the existing software assurance or what is commonly called software security knowledge, methodologies and what information security technologies is currently being recommended by the information technology community. Finally it is demonstrated how this security knowledge could be incorporated into the curriculum for undergraduate software engineering.


Comparing Group Means When Nonresponse Rates Differ, Gabriela M. Stegmann Jan 2015

Comparing Group Means When Nonresponse Rates Differ, Gabriela M. Stegmann

UNF Graduate Theses and Dissertations

Missing data bias results if adjustments are not made accordingly. This thesis addresses this issue by exploring a scenario where data is missing at random depending on a covariate x. Four methods for comparing groups while adjusting for missingness are explored by conducting simulations: independent samples t-test with predicted mean stratification, independent samples t-test with response propensity stratification, independent samples t-test with response propensity weighting, and an analysis of covariance. Results show that independent samples t-test with response propensity weighting and analysis of covariance can appropriately adjust for bias. ANCOVA is the stronger method when …


Reconciling The Two Cultures : A Case Study Of The University Of Northern Iowa, Elizabeth Ann Collins Jan 2015

Reconciling The Two Cultures : A Case Study Of The University Of Northern Iowa, Elizabeth Ann Collins

Dissertations and Theses @ UNI

In 1959, chemist and author Charles Percy Snow gave a Rede Lecture at the University of Cambridge in which he named “Two Cultures”—the sciences and the humanities—which, according to his experience as someone who worked in both, were at odds with one another. His words elicited impassioned responses from critics who either agreed with Snow, believing this to be a detriment to society, or vehemently disagreed, believing Snow’s statements to be unfounded, and even antagonistic. This conversation, which had also found relevance in the United States, continues to be important today, and has changed over the years as institutions of …


Relativistic Configuration Interaction Calculations Of The Atomic Properties Of Selected Transition Metal Positive Ions; Ni Ii, V Ii And W Ii, Marwa Hefny Abdalmoneam Jan 2015

Relativistic Configuration Interaction Calculations Of The Atomic Properties Of Selected Transition Metal Positive Ions; Ni Ii, V Ii And W Ii, Marwa Hefny Abdalmoneam

Dissertations, Master's Theses and Master's Reports

Relativistic Configuration Interaction (RCI) method has been used to investigate atomic properties of the singly ionized transition metals including Nickel (Ni II), Vanadium (V II), and Tungsten (W II). The methodology of RCI computations was also improved. Specifically, the method to shift the energy diagonal matrix of the reference configurations was modified which facilitated including the effects of many electronic configurations that used to be difficult to be included in the energy matrix and speeded-up the final calculations of the bound and continuum energy spectrum. RCI results were obtained for three different cases:

  1. Atomic moments and polarizabilities of Ni II; …


The 2009 And 2011 Hazard Events At San Vicente Volcano, El Salvador: Vulnerability, Resettlement, And Disaster Risk Reduction, Luke Bowman Jan 2015

The 2009 And 2011 Hazard Events At San Vicente Volcano, El Salvador: Vulnerability, Resettlement, And Disaster Risk Reduction, Luke Bowman

Dissertations, Master's Theses and Master's Reports

Scientists from a variety of disciplines have made major advancements in the geophysical and social aspects of hazard science. Despite these advancements, economic losses and the number of people affected by disasters continue to rise. The field of disaster risk reduction (DRR) attempts to counter this rising trend of disaster losses by integrating a variety of disciplines to holistically solve complex problems related to risk and vulnerability. Frequent disasters in El Salvador provide insight into the evolution of DRR and its application during and after two hydrometeorological disasters in the department of San Vicente in 2009 and 2011. This dissertation …


Impact Of Antecedent Groundwater Heads And Transient Aquifer Storage On Flood Peak Attenuation In An Unconfined Karst Aquifer: Study Of The Upper Suwannee River, Florida, Usa., Jeremy Loucks Jan 2015

Impact Of Antecedent Groundwater Heads And Transient Aquifer Storage On Flood Peak Attenuation In An Unconfined Karst Aquifer: Study Of The Upper Suwannee River, Florida, Usa., Jeremy Loucks

Dissertations, Master's Theses and Master's Reports

Flood peak attenuation is an important aspect of understanding flooding and its effects. Few studies exist that look at the effects of ground-surface water interactions in regards to peak attenuation, and fewer still focus on karst environments. In the karstic, variably confined Suwannee River Basin, discharge, river stage, and water table data that were collected over a ten-year period were analyzed to determine the relationship between antecedent groundwater head and flood peak attenuation. Flooding causes high hydraulic heads in the river, which rise faster than corresponding groundwater heads. Springs which normally feed groundwater into the river reverse flow, and conduits …


Extracting Flow Features Using Bag-Of-Features And Supervised Learning Techniques, Yifei Li Jan 2015

Extracting Flow Features Using Bag-Of-Features And Supervised Learning Techniques, Yifei Li

Dissertations, Master's Theses and Master's Reports

Measuring the similarity between two streamlines is fundamental to many important flow data analysis and visualization tasks such as feature detection, pattern querying and streamline clustering. This dissertation presents a novel streamline similarity measure inspired by the bag-of-features concept from computer vision. Different from other streamline similarity measures, the proposed one considers both the distribution of and the distances among features along a streamline. The proposed measure is tested in two common tasks in vector field exploration: streamline similarity query and streamline clustering. Compared with a recent streamline similarity measure, the proposed measure allows users to see the interesting features …


Insights Into The Relationship Between Mixing Duration And Volcanic Explosivity Index (Vei): Pacaya And Fuego Volcanoes, Guatemala, Nicola Mari Jan 2015

Insights Into The Relationship Between Mixing Duration And Volcanic Explosivity Index (Vei): Pacaya And Fuego Volcanoes, Guatemala, Nicola Mari

Dissertations, Master's Theses and Master's Reports

This study investigates whether the timing of magma mixing phenomena could be related to explosivity and style of volcanic activity. Lava flow and tephra samples, derived from observed, energetically-diverse eruptions, from Pacaya and Fuego volcanoes (Guatemala), were studied, the Volcanic Explosivity Index (VEI) was used as an indicator of eruption intensity. Polarized light microscopy and Scanning Electron Microscopy (SEM) techniques were used for textural and geochemical measurements. Results are interpreted as evolution of mixing through changes in textures of plagioclase and olivine crystals. These suggest that boxy-cellular plagioclase (high frequency in VEI 0 samples) is associated with brief mixing residence …


Multi-Instrumental Investigation Of Volcanic Outgassing At Pacaya Volcano, Guatemala., Carlo Prandi Jan 2015

Multi-Instrumental Investigation Of Volcanic Outgassing At Pacaya Volcano, Guatemala., Carlo Prandi

Dissertations, Master's Theses and Master's Reports

Pacaya is one of the most active volcano in the world and it is only ≈30Km South of Guatemala City, the capital of Guatemala, that has a population of about 2 million of people and a surrounding metropolitan area where ≈4.5 million of people live. So mitigate the volcanic hazard improving the knowledge and the understanding of Pacaya is fundamental to decrease the risk factor at which the surrounding population is exposed. This study aims to furnish a new large database, the analysis, the comparison and the interpretations of data that come from different techniques of sampling, about the volcanic …


Analysis Of No2 And Hcho Vertical Column Densities In The Great Lakes Region Using The Ozone Monitoring Instrument, David J. Faber Jan 2015

Analysis Of No2 And Hcho Vertical Column Densities In The Great Lakes Region Using The Ozone Monitoring Instrument, David J. Faber

Dissertations, Master's Theses and Master's Reports

Nitrogen oxides (NOx) and volatile organic compounds (VOC) are major contributors to air quality, especially for their direct involvement in ozone (O3) production. Retrievals of nitrogen dioxide (NO2) and formaldehyde (HCHO) mixing ratios can be used to represent NOx and VOCs respectively and the formaldehyde-to-NO2 ratio (FNR) can be used to analyze the O3 production chemistry in a region. Since the current monitoring network in the Great Lakes region for NO2 and HCHO is limited, the Ozone Monitoring Instrument (OMI) can be used to retrieve vertical column densities for NO2 and HCHO in rural areas away from ground-based sensors. OMI …


The Bootstrap Estimation In Time Series, Yun Liu Jan 2015

The Bootstrap Estimation In Time Series, Yun Liu

Dissertations, Master's Theses and Master's Reports

Time series, a special case in dependent data sequence, is widely used in many fields. In time series, linear process models are quite popularly used. General form of linear process indicates the time dependence property of time series, AR(p), MA(q) and ARMA(p;,q) models are all linear process models. In this report, simulations are based on the simplest models of these linear process models, such as AR(1), MA(1) and ARMA(1,1) models. AR(1)-SEASON, which is developed based on AR(1) model by changing the weight of residuals, is also considered in this report. To deal with dependent data sequence, common methods which aim …


Legacy And Opportunity In Northern Hardwood Forests, Wilfred Previant Jan 2015

Legacy And Opportunity In Northern Hardwood Forests, Wilfred Previant

Dissertations, Master's Theses and Master's Reports

Northern hardwood management reflects a combination of historic exploitation, current efforts for sustainability, and a desired future condition that incorporates complexity, resiliency, and adaptability. Stand structure and species diversity were assessed at two study locations within Michigan (USA): (1) long-term northern hardwood cutting trials at the Ford Forestry Center (FFC; Michigan Technological University, USA); and (2) vernal pool habitat within Pictured Rocks National Lakeshore (PRNL). Following the fifth cutting entry at the FFC, age structure and pre- and post-harvest relative species abundance, stocking, and volume were compared across three diameter-limit treatments, three residual basal area treatments, and an uncut control. …


Laboratory And Field Investigation Of Mixing, Morphology And Optical Properties Of Soot And Secondary Organic Aerosols, Noopur Sharma Jan 2015

Laboratory And Field Investigation Of Mixing, Morphology And Optical Properties Of Soot And Secondary Organic Aerosols, Noopur Sharma

Dissertations, Master's Theses and Master's Reports

Soot/ black carbon particles are believed to be the second largest anthropogenic contributor to the Earth’s radiative forcing, and are emitted from combustion processes. Freshly emitted soot has a fractal-like structure in which monomers are arranged into branched chain-like configuration. In the atmosphere, soot mixes with and is processed by interacting with other co-existing particle and vapors. The processing that soot undergo after emission alters its morphology; for example, condensation of vapors results into coated, mixed or compacted soot depending upon the environmental conditions. Changes in soot morphology have a strong and direct influence on its optical properties.

The unique …


Decomposing The Blocks Of A Steiner Triple System Of Order 4v-3 Into Partial Parallel Classes Of Size V-1, Leah C. Tollefson Jan 2015

Decomposing The Blocks Of A Steiner Triple System Of Order 4v-3 Into Partial Parallel Classes Of Size V-1, Leah C. Tollefson

Dissertations, Master's Theses and Master's Reports

In this report we present a summary and our new results on finding partial parallel classes of uniform size of Steiner triple systems, STS(v). We show several results for STS(4v - 3), where v = 3 mod 12 and v = 9 mod 12. In Chapter 1 we provide background knowledge and introduce the problem. In Chapter 2 we discuss some important known results to the problem, introduce the needed ingredients, and explain the methodology of the construction. Finally, in Chapter 3, we conclude with a summary and discuss possibilities for future work.


Enabling Techniques For Expressive Flow Field Visualization And Exploration, Jun Tao Jan 2015

Enabling Techniques For Expressive Flow Field Visualization And Exploration, Jun Tao

Dissertations, Master's Theses and Master's Reports

Flow visualization plays an important role in many scientific and engineering disciplines such as climate modeling, turbulent combustion, and automobile design. The most common method for flow visualization is to display integral flow lines such as streamlines computed from particle tracing. Effective streamline visualization should capture flow patterns and display them with appropriate density, so that critical flow information can be visually acquired. In this dissertation, we present several approaches that facilitate expressive flow field visualization and exploration. First, we design a unified information-theoretic framework to model streamline selection and viewpoint selection as symmetric problems. Two interrelated information channels are …


Deterministic And Stochastic Inversion Techniques Used To Predict Porosity: A Case Study From F3-Block, Hao Wu Jan 2015

Deterministic And Stochastic Inversion Techniques Used To Predict Porosity: A Case Study From F3-Block, Hao Wu

Dissertations, Master's Theses and Master's Reports

Within large-scale sigmoidal bedding of the F3-block in the shallow zone there appear to be some indicators of hydrocarbon deposits. In order to characterize target zone in the sigmoidal bedding, I combine the analysis of inverted results of post-stack seismic data with rock-physics relationships developed from well log data to predict the porosity, which ranges from 20% to 33%, for different system tracts in this area. The methods used in this study include conventional deterministic inversion and novel stochastic inversion. Through a rock physics analysis of the density, velocity and gamma-ray logs in two wells, I constructed relationships between the …