Physical Sciences and Mathematics Commons^™

Semantic Similarity Detection In Natural Language Documents, Lianyu Zhao

All Theses

Data leak prevention (DLP) solutions monitor and control data flow. Current techniques find data that matches user defined syntactic patterns. Unfortunately, large classes of DLP relevant data are defined by information semantics, rather than data syntax. Syntax refers to data format, whereas semantics refers to data meaning. The class of social security numbers can be adequately expressed using data syntax, whereas a new industrial process can only be adequately described using information semantics. In this paper, we propose methods for extracting and identifying document semantics using training sets of limited size (tens of documents). The first method is based on …

Clustering Of Sloan Digital Sky Survey Iii Photometric Luminous Galaxies: The Measurement, Systematics, And Cosmological Implications, Shirley Ho, Antonio J. Cuesta, Hee-Jong Seo, Roland De Putter, Ashley J. Ross, Martin White, Nikhil Padmanabhan, Shun Saito, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

The Sloan Digital Sky Survey (SDSS) surveyed 14,555 deg², and delivered over a trillion pixels of imaging data. We present a study of galaxy clustering using 900,000 luminous galaxies with photometric redshifts, spanning between z = 0.45 and z = 0.65, constructed from the SDSS using methods described in Ross et al. This data set spans 11,000 deg² and probes a volume of 3 h^-3 Gpc³, making it the largest volume ever used for galaxy clustering measurements. We describe in detail the construction of the survey window function and various systematics affecting our measurement. …

The Update, December 2012, University Of Northern Iowa. College Of Humanities, Arts And Sciences.

Update

Inside this issue:
-- Having a Field Day: UNI Students Attend Geology Camp in Wyoming
--Contents December 2012
-- Department News
-- Art Students Present Research Papers at Midwest Humanities Conference
-- School of Music Events
-- Challenging Bullying Through Art
-- Alumni Spotlight: James Arns: Physics
-- UNI Forensics Team

Swift Follow-Up Observations Of Candidate Gravitational-Wave Transient Events, P. A. Evans, J. K. Fridriksson, N. Gehrels, J. Homan, J. P. Osborne, M. Siegel, A. Beardmore, P. Handbauer, J. Gelbord, J. A. Kennea, M. Smith, Q. Zhu, J. Aasi, J. Abadie, B. P. Abbott, R. Abbott, T. D. Abbott, M. Abernathy, T. Accadia, F. Acernese, C. Adams, T. Adams, P. Addesso, R. Adhikari, C. Affeldt, M. Agathos, K. Agatsuma, P. Ajith, B. Allen, A. Allocca, E. Amador Ceron, Tiffany Z. Summerscales

Faculty Publications

We present the first multi-wavelength follow-up observations of two candidate gravitational-wave (GW) transient events recorded by LIGO and Virgo in their 2009-2010 science run. The events were selected with low latency by the network of GW detectors (within less than 10 minutes) and their candidate sky locations were observed by the Swift observatory (within 12 hr). Image transient detection was used to analyze the collected electromagnetic data, which were found to be consistent with background. Off-line analysis of the GW data alone has also established that the selected GW events show no evidence of an astrophysical origin; one of them …

Assessment Of Passive Fire Protection On Steel-Girder Bridges, Michael Davidson

Masters Theses & Specialist Projects

Bridges in the US are severely damaged or suffer collapse from fires at significant rates, even when compared to other hazards such as earthquakes. Fire-induced bridge collapses are perpetuated by the general lack of installed fire protection systems. Therefore, new materials and applications are needed to mitigate structural damage that can be caused to civil infrastructure by severe fires. Accordingly, the objective of this study is to further the development of new fire protection applications in transportation structures. Specifically, the investigation centers on the development of new applications in passive fire protection materials, within the context of shielding steel-girder bridges …

Polymer Surface Engineering Via Thiol-Mediated Reactions, Ryan Matthew Hensarling

Dissertations

Synthesis of polymer brushes to decorate a surface with desired functionality typically involves surface-initiated polymerization (SIP) of functional, but non-reactive monomers. This approach suffers major drawbacks associated with synthesizing sufficiently thick polymer brushes containing surface-attached polymer chains of high molecular weight at high grafting density (i.e. cost, synthetic effort and functional group intolerance during polymerization). The research herein seeks to circumvent these limitations by the decoration of surfaces with polymer chains bearing specific pendent functional groups amenable to post-polymerization modification (PPM). In particular, this dissertation leverages PPM via a specific class of click reactions – thiol-click – that 1) enables …

Fuzzy-Excom Software Project Risk Assessment, Luiz Fernando Capretz, Ekananta Manalif, Ali Bou Nassif, Danny Ho

Electrical and Computer Engineering Publications

A software development project can be considered to be risky project due to the uncertainty of the information (customer requirements), the complexity of the process, and the intangible nature of the product. Under these conditions, risk management in software development projects is mandatory, but often it is difficult and expensive to implement.

Expert COCOMO is an efficient approach to software project risk management, which leverages existing knowledge and expertise from previous effort estimation activities to assess the risk in a new software project. However, the original method has a limitation because it cannot effectively deal with imprecise and uncertain inputs …

Chemical Contaminants As Stratigraphic Markers For The Anthropocene, Michael A. Kruge

Department of Earth and Environmental Studies Faculty Scholarship and Creative Works

Thousands and even millions of years from now, widespread anthropogenic contaminants in sediments would likely persist, incorporated into the geological record. They would inadvertently preserve evidence of our present era (informally designated as the Anthropocene Epoch) characterized by large human populations engaged in intensive industrial and agricultural activities.

Hypothetical geologists in the distant future would likely find unusually high concentrations of a wide variety of contaminants at stratigraphic levels corresponding to our present time, analogous to the iridium anomaly marking the bolide impact event at the close of the Cretaceous Period. These would include both organic and inorganic substances, such …

Swift Follow-Up Observations Of Candidate Gravitational-Wave Transient Events, P. A. Evans, J. K. Fridriksson, N. Gehrels, J. Homan, J. P. Osborne, M. Siegel, A. Beardmore, P. Handbauer, J. Gelbord, J. A. Kennea, M. Smith, Q. Zhu, J. Aasi, J. Abadie, B. P. Abbott, R. Abbott, T. D. Abbott, M. Abernathy, T. Accadia, F. Acernese, C. Adams, T. Adams, P. Addesso, R. Adhikari, C. Affeldt, M. Agathos, K. Agatsuma, P. Ajith, B. Allen, A. Allocca

Physics and Astronomy Faculty Publications and Presentations

We present the first multi-wavelength follow-up observations of two candidate gravitational-wave (GW) transient events recorded by LIGO and Virgo in their 2009-2010 science run. The events were selected with low latency by the network of GW detectors (within less than 10 minutes) and their candidate sky locations were observed by the Swift observatory (within 12 hr). Image transient detection was used to analyze the collected electromagnetic data, which were found to be consistent with background. Off-line analysis of the GW data alone has also established that the selected GW events show no evidence of an astrophysical origin; one of them …

Identification Of Tcp Protocols, Juan Shao

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

Recently, many new TCP algorithms, such as BIC, CUBIC, and CTCP, have been deployed in the Internet. Investigating the deployment statistics of these TCP algorithms is meaningful to study the performance and stability of the Internet. Currently, there is a tool named Congestion Avoidance Algorithm Identification (CAAI) for identifying the TCP algorithm of a web server and then for investigating the TCP deployment statistics. However, CAAI using a simple k-NN algorithm can not achieve a high identification accuracy. In this thesis, we comprehensively study the identification accuracy of five popular machine learning models. We find that the random forest model …

Investigations Of Inter- And Intramolecular C-O Bond Forming Reactions Of Peroxide Electrophiles, Benjamin W. Puffer

Department of Chemistry: Dissertations, Theses, and Student Research

A common reaction to yield ethers relies on an alkoxide nucleophile and a carbon electrophile (Williamson ether formation). Ethers can also be formed by reactions with carbon nucleophiles and oxygen electrophiles by way of the peroxide functional group. We screened a number of carbon nucleophiles suitable for attack on dialkyl peroxides to form new C-O bonds. Also a novel approach using a peroxyketal electrophile is shown to increase the efficiency of this intermolecular reaction. This method of C-O bond formation can also be implemented intramolecularly, not seen before in the literature, to yield cyclic ethers. This approach requires the generation …

Molecular Processes In Astrophysics: Calculations Of H + H2 Excitation, De-Excitation, And Cooling, Matthew Kelley

UNLV Theses, Dissertations, Professional Papers, and Capstones

The implications of H+H2 cooling in astrophysics is important to several applications. One of the most significant and pure applications is its role in cooling in the early universe. Other applications would include molecular dynamics in nebulae and their collapse into stars and astrophysical shocks. Shortly after the big bang, the universe was a hot primordial gas of photons, electrons, and nuclei among other ingredients. By far the most dominant nuclei in the early universe was hydrogen. In fact, in the early universe the matter density was 90 percent hydrogen and only 10 percent helium with small amounts of lithium …

Changing Demands From Riparian Evapotranspiration And Free-Water Evaporation In The Lower Colorado River Basin Under Different Climate Scenarios, Daniel Bunk

UNLV Theses, Dissertations, Professional Papers, and Capstones

Observed and projected trends in riparian evapotranspiration (ET) and free-water evaporation are examined in this study to help improve water demand forecasting, particularly in modeling of lower Colorado River system reservoir operations. While most previous research in the Colorado River basin have focused on the impacts of climate change and climate variability on water supply, the impacts of changing climate on water demand have not been adequately addressed. Changes in temperature, precipitation, and wind patterns are expected to increase evaporative demands in the lower Colorado River mainstream, including free-water evaporation and ET from riparian vegetation, and may also impact infiltration …

Restoration Of Biological Soil Crust On Disturbed Gypsiferous Soils In Lake Mead National Recreation Area, Eastern Mojave Desert, Lindsay P. Chiquoine

UNLV Theses, Dissertations, Professional Papers, and Capstones

Biological soil crusts (BSCs) are sensitive to anthropogenic disturbances. Natural recovery takes many years. Active restoration decreases recovery time. Native BSC inocula, which included lichens and mosses, salvaged from gypsiferous soil habitats in Lake Mead National Recreation Area (LMNRA) in the eastern Mojave Desert were stored dry for two years and applied to disturbed soil after a road reconstruction in LMNRA and also used in laboratory experiments to test inoculation technique effectiveness. After 18 months, field results revealed positive relationships between inoculation and the presence of macroscopic BSC cover, cyanobacteria abundance, soil stability, and ammonium concentrations. Chlorophyll fluorescence monitoring of …

A Gauge Theoretic Treatment Of Rovibrational Motion In Diatoms, Gregory Colarch

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Born-Oppenheimer approximation has long been the standard approach to solving the Schrödinger equation for diatomic molecules. In it, nuclear and electronic motions are separated into "slow" and "fast" degrees of freedom and couplings between the two are ignored. The neglect of non-adiabatic couplings leads to an incomplete description of diatomic motion, and in a more refined approach, non-adiabatic couplings are uncoupled by transforming the angular momentum of the molecule and electrons into the body-fixed frame.

In this thesis we examine a "modern" form of the Born-Oppenheimer approximation by exploiting a gauge theoretic approach in a description of molecular motion. …

Elemental Contributions From Minor And Major Constituents Of Bone On The Separation Of Radiostrontium, Ashlee Rae Dailey

UNLV Theses, Dissertations, Professional Papers, and Capstones

While many methods exist to separate and analyze radionuclides from a variety of environmental matrices, the performance of all of these methods is often limited by other interfering constituents that are consistently found in most of these samples. The presence of such constituents can significantly reduce the recovery of the radioisotopes of interests and lead to incomplete separations.

Strontium has the same oxidation state and a similar atomic radius as calcium and is therefore readily able to substitute for calcium in lattice sites. This similarity in behavior leads to the preferential accumulation of strontium in newly formed bone. The study …

Hardware-Software Co-Design, Acceleration And Prototyping Of Control Algorithms On Reconfigurable Platforms, Desta Kumsa Edosa

UNLV Theses, Dissertations, Professional Papers, and Capstones

Differential equations play a significant role in many disciplines of science and engineering. Solving and implementing Ordinary Differential Equations (ODEs) and partial Differential Equations (PDEs) effectively are very essential as most complex dynamic systems are modeled based on these equations. High Performance Computing (HPC) methodologies are required to compute and implement complex and data intensive applications modeled by differential equations at higher speed. There are, however, some challenges and limitations in implementing dynamic system, modeled by non-linear ordinary differential equations, on digital hardware. Modeling an integrator involves data approximation which results in accuracy error if data values are not considered …

Comparison And Simulation Of Salt-Ceramic Composites For Use In High Temperature Concentrated Solar Power, Lauren Michelle Fossile

UNLV Theses, Dissertations, Professional Papers, and Capstones

Due to the inherently intermittent nature of solar energy caused by cloud cover among other sources, thermal storage systems are needed to make solar energy more consistent. This same technology could be used to prolong the daily number of useful hours of solar energy power plants. Salt-ceramic materials are a relatively new prospect for heat storage, but have been researched mostly with magnesium oxide and several different carbonate salts. Salt ceramics are a phase change material where the salt changes phase inside the ceramic structure allowing for the system to use the sensible heat of both materials and the latent …

Recycling And Reuse Of Radioactive Materials, Thomas Joseph O'Dou

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Radiochemistry Program at the University of Nevada, Las Vegas (UNLV) has a Radiation Protection Program that was designed to provide students with the ability to safely work with radioactive materials in quantities that are not available in other academic environments. Requirements for continuous training and supervision make this unique program capable of turning out graduates that have an understanding of contamination and dose control techniques that complement their knowledge of the elements that they work with. The Program has also adopted a radionuclide recovery and reuse program that has provided materials from other universities, government agencies, and private companies …

Topics In Galaxy Formation: Pairwise Velocities Of Dark Matter Halos And Molecular Hydrogen Regulated Star Formation In Cosmological Simulations, Robert Jo Thompson

UNLV Theses, Dissertations, Professional Papers, and Capstones

In this dissertation we investigate two distinct challenges within the concordance LCDM model and an unrelated project.

The first is a discrepancy between theory and observation. A massive galaxy sub-cluster known as the `bullet' has fallen through a more massive parent galaxy cluster at a redshift of z=0.296.

Theory finds that in order to reproduce the observational quantities of this cluster, an unusually high relative velocity of v12=3000 km/s between the two cluster's parent halos is required.

We quantify the statistical probability of producing a `bullet-like' halo pair within large N-body simulations, and

conclude that either the LCDM model is …

Detrital Carbonates In A Sequence Stratigraphic Framework: An Example From The Furongian Slope Environment In The Hot Creek Range Of Central Nevada, Leon Taufani

UNLV Theses, Dissertations, Professional Papers, and Capstones

An integrated sedimentological study of detrital carbonates of the late Cambrian (Furongian) Hales Limestone in central Nevada was conducted in order to model facies distribution and controlling mechanisms of carbonate gravity-flow deposits. Seven closely-spaced sections and numerous traceable short sections were measured to investigate temporal and spatial changes of detrital carbonates within a high-resolution stratigraphic framework supported by biostratigraphic and carbon isotope chemostratigraphic constraints and by key physical surfaces. Polished slabs and thin section petrographic analysis were used to identify micro- and macro-scale textures and diagenesis.

Ten lithofacies are identified from the Hales Limestone. Lateral tracing of these facies reveals …

Eliciting Usable Gestures For Multi-Display Environments, Teddy Seyed, Chris Burns, Mario Costa Sousa, Frank Maurer, Anthony Tang

Research Collection School Of Computing and Information Systems

Multi-display environments (MDEs) have advanced rapidly in recent years, incorporating multi-touch tabletops, tablets, wall displays and even position tracking systems. Designers have proposed a variety of interesting gestures for use in an MDE, some of which involve a user moving their hands, arms, body or even a device itself. These gestures are often used as part of interactions to move data between the various components of an MDE, which is a longstanding research problem. But designers, not users, have created most of these gestures and concerns over implementation issues such as recognition may have influenced their design. We performed a …

Fame, Soft Flock Formation Control For Collective Behavior Studies And Rapid Games Development, Choon Sing Ho, Yew-Soon Ong, Xianshun Chen, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

We present FAME, a comprehensive C# software library package providing soft formation control for large flocks of agents. While many existing available libraries provide means to create flocks of agent equipped with simple steering behavior, none so far, to the best of our knowledge, provides an easy and hassle free approach to control the formation of the flock. Here, besides the basic flocking mechanisms, FAME provides an extensive range of advanced features that gives enhanced soft formation control over multiple flocks. These soft formation features include defining flocks in any user-defined formation, automated self-organizing agent within formation, manipulating formation shape …

An Automated Pathological Class Level Annotation System For Volumetric Brain Images, Thien Anh Dinh, Tomi Silander, C. C. Tchoyoson Lim, Tze-Yun Leong

Research Collection School Of Computing and Information Systems

We introduce an automated, pathological class level annotation system for medical volumetric brain images. While much of the earlier work has mainly focused on annotating regions of interest in medical images, our system does not require annotated region level training data nor assumes perfect segmentation results for the regions of interest; the time and effort needed for acquiring training data are hence significantly reduced. This capability of handling high-dimensional noisy data, however, poses additional technical challenges, since statistical estimation of models for such data is prone to over-fitting. We propose a framework that combines a regularized logistic regression method and …

Investigating Intelligent Agents In A 3d Virtual World, Yilin Kang, Fiona Fui-Hoon Nah, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

Web 3.0 involves "intelligent" web applications that utilize natural language processing, machine-based learning and reasoning, and intelligent techniques to analyze and understand user behavior. In this research, we empirically assess a specific form of Web 3.0 application in the form of intelligent agents that offer assistance to users in the virtual world. Using media naturalness theory, we hypothesize that the use of intelligent agents in the virtual world can enhance user experience by offering a more natural way of communication and assistance to users. We are interested to test if media naturalness theory holds in the context of intelligent agents …

Knowledge-Based Exploration For Reinforcement Learning In Self-Organizing Neural Networks, Teck-Hou Teng, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

Exploration is necessary during reinforcement learning to discover new solutions in a given problem space. Most reinforcement learning systems, however, adopt a simple strategy, by randomly selecting an action among all the available actions. This paper proposes a novel exploration strategy, known as Knowledge-based Exploration, for guiding the exploration of a family of self-organizing neural networks in reinforcement learning. Specifically, exploration is directed towards unexplored and favorable action choices while steering away from those negative action choices that are likely to fail. This is achieved by using the learned knowledge of the agent to identify prior action choices leading to …

Agent-Based Virtual Humans In Co-Space: An Evaluative Study, Yilin Kang, Ah-Hwee Tan, Fiona Fui-Hoon Nah

Research Collection School Of Computing and Information Systems

Co-Space refers to interactive virtual environment modelled after the real world in terms of look-and-feel, functionalities and services. We have developed a 3D virtual world named Nan yang Technological University (NTU) Co-Space populated with virtual human characters. Three key requirements of realistic virtual humans in the virtual world have been identified, namely (1) autonomy: agents can function on their own, (2) interactivity: agents can interact naturally with players, and (3) personality: agents can exhibit human traits and characteristics. Working towards these challenges, we propose a brain-inspired agent architecture that integrates goal-directed autonomy, natural language interaction and human-like personality. We conducted …

Visualization For Anomaly Detection And Data Management By Leveraging Network, Sensor And Gis Techniques, Zhaoxia Wang, Chee Seng Chong, Rick S. M. Goh, Wanqing Zhou, Dan Peng, Hoong Chor Chin

Research Collection School Of Computing and Information Systems

This paper studies the importance of visualization for discerning and interpreting patterns of data and its application for solving real problems, such as anomaly detection and data management. There are various ways to realize visualization to cater to the needs of numerous real life applications. Depending on needs, a combination of some of these ways may be required for presenting an effective visualization. The authors present visualization schemes for anomaly detection/condition monitoring and data management by leveraging network techniques and combining them with modern techniques such as sensor, database, mobile communication, GPS and GIS techniques. Two case studies are presented …

Reputation As Public Policy For Internet Security: A Field Study, Qian Tang, Leigh L. Linden, John S. Quarterman, Andrew Whinston

Research Collection School Of Computing and Information Systems

Cybersecurity is a national priority in this big data era. Because of the lack of incentives and the existence of negative externality, companies often underinvest in addressing security risks and accidents, despite government and industry recommendations. In the present article, we propose a method that utilizes reputation through information disclosure to motivate companies to behave pro-socially, improving their Internet security. Using outbound spam as a proxy for Internet security, we conducted a quasiexperimental field study for eight countries through SpamRankings.net. This outgoingspam-based study shows that information disclosure on outgoing spam can help reduce outgoing spam, approximately by 16 percent. This …

Cost-Sensitive Online Classification, Jialei Wang, Peilin Zhao, Steven C. H. Hoi

Research Collection School Of Computing and Information Systems

Both cost-sensitive classification and online learning have been extensively studied in data mining and machine learning communities, respectively. However, very limited study addresses an important intersecting problem, that is, “Cost-Sensitive Online Classification". In this paper, we formally study this problem, and propose a new framework for Cost-Sensitive Online Classification by directly optimizing cost-sensitive measures using online gradient descent techniques. Specifically, we propose two novel cost-sensitive online classification algorithms, which are designed to directly optimize two well-known cost-sensitive measures: (i) maximization of weighted sum of sensitivity and specificity, and (ii) minimization of weighted misclassification cost. We analyze the theoretical bounds of …