Physical Sciences and Mathematics Commons^™

First-Principles Studies On Physical And Chemical Properties Of Nanostructures, Menghao Wu

Department of Physics and Astronomy: Dissertations, Theses, and Student Research

The physical and chemical properties of decorated graphene and graphene ribbons, single-layer III-V systems, three-dimensional carbon and BN foam, and transition-metal-molecular sandwich nanowires have been investigated by first-principle calculations and their potential applications have been predicted. First, it is shown that zigzag graphene nanoribbons (ZGNRs) can be converted into half metal when their edges are decorated by some chemical functional groups, and the half-metalicity is induced by chemical potential difference between two edges when one edge is decorated by electron-donating group like –OH and the other edge is decorated by electron-accepting group like –F, -NH₂, -N(CH₃) …

Hydroclimatic Forecasting In The Western United States Using Paleoclimate Reconstructions And Data-Driven Models, Christopher Allen Carrier

UNLV Theses, Dissertations, Professional Papers, and Capstones

This thesis investigated climate variability and their associated hydrologic responses in the western United States. The western United States faces the problem of water scarcity, where the management and mitigation of available water supplies are further complicated by climate variability. Climate variability associated with the phases of oceanic-atmospheric oscillations has been shown to influence streamflow and precipitation, where predictive relationships have led to the possibility of producing long-range forecasts. Based on literature review, four oceanic-atmospheric oscillation indices were identified in having the most prominent influence over the western United States including the El Niño - Southern Oscillation (ENSO), Pacific Decadal …

Bryoecology In The American Southwest: Patterns Of Biodiversity And Responses To Global Change, John Carroll Brinda

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation combines investigation of the large-scale responses of bryophyte species diversity and distribution with small-scale physiological adaptations to global change. These two areas of inquiry are linked because one way to predict plant species responses to global change is to examine their distribution across current ecological gradients produced by factors such as latitude and elevation. By examining these biogeographic patterns one can identify those species that have a narrow tolerance and therefore are most sensitive to change. Selected bryophytes might then be used as indicator species in long-term monitoring programs. Where historical data exist, these can be used to …

Paired Positive Carbonate Carbon Isotope, Organic Carbon Isotope, And Oxygen Isotope Composition Study Across The Lower Mississippian Positive Carbon Isotope Excursion, Southeastern Nevada, Usa, Robert Alan Henry

UNLV Theses, Dissertations, Professional Papers, and Capstones

A prominent positive carbonate carbon isotope (delta13Ccarb) excursion of Early Mississippian age (ca 351 Ma) has been documented by previous studies from numerous sites globally. This delta13Ccarb excursion has been interpreted as resulting from enhanced organic carbon burial that removed 13C-depleted carbon from the ocean and atmosphere. Anticipated outcomes from enhanced organic carbon burial would include a similar positive excursion in organic carbon isotopes (delta13Corg) and a global cooling event resulting from reduced CO2 in the atmosphere and ocean. These predictions, however, were not tested sufficiently in previous studies. This research has tested these predictions through an integrated study of …

Spectroscopic Studies Of Melamine At High Pressure, Martin Donald Galley

UNLV Theses, Dissertations, Professional Papers, and Capstones

We have performed mid- and far- Infra Red (IR) absorption, Raman spectroscopy, and angular dispersive x-ray diffraction (XRD) studies on melamine under high pressure and room temperature. We have verified the presence of two prior reported phase transitions, the first between 1-2 GPa, and the second between 7-9 GPa. We have also found evidence of a third unreported phase transition between 14-16 GPa, during which, there was a sudden disappearance of all low energy peaks (^-1 ) in both the Raman and IR spectra. The far-IR peak movement experiences a discontinuity as the rate of peak movement suddenly changes. …

Processj: A Process-Oriented Programming Language, Matthew Sowders

UNLV Theses, Dissertations, Professional Papers, and Capstones

Java is a general purpose object-oriented programming language that has been widely adopted. Because of its high adoption rate and its lineage as a C-style language, its syntax is familiar to many programmers. The downside is that Java is not natively concurrent. Volumes have been written about concurrent programming in Java; however, concurrent programming is difficult to reason about within an object-oriented paradigm and so is difficult to get right.

occam -π is a general purpose process-oriented programming language. Concurrency is part of the theoretical underpinnings of the language. Concurrency is simple to reason about within an occam -π application …

Quantification Of Stochastic Uncertainty Propagation For Monte Carlo Depletion Methods In Reactor Analysis, Quentin Thomas Newell

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Monte Carlo method provides powerful geometric modeling capabilities for large problem domains in 3-D; therefore, the Monte Carlo method is becoming popular for 3-D fuel depletion analyses to compute quantities of interest in spent nuclear fuel including isotopic compositions. The Monte Carlo approach has not been fully embraced due to unresolved issues concerning the effect of Monte Carlo uncertainties on the predicted results.

Use of the Monte Carlo method to solve the neutron transport equation introduces stochastic uncertainty in the computed fluxes. These fluxes are used to collapse cross sections, estimate power distributions, and deplete the fuel within depletion …

Environmental Impact Of The Three Kids Mine Tailings, Henderson, Nv, Ji Hye Park

UNLV Theses, Dissertations, Professional Papers, and Capstones

This research focused on the distribution of the Three Kids Mine tailings in surface soils in and around the mine in Henderson, Nevada. It is situated next to the communities of Calico Ridge and Lake Las Vegas Resort, and, just the west of the Lake Mead Recreation area. Even though the mine has been inactive for almost 50 years (1917-1961), tailing piles and other sources of contamination on the mine are currently exposed to the atmosphere. In this study, surface soil samples were collected along eight transects emanating from the center of Three Kids Mine tailing piles up to five …

Wsm 2011: Third Acm Workshop On Social Media, Steven C. H. Hoi, Michal Jacovi, Ioannis Kompatsiaris, Jiebo Luo, Konstantinos Tserpes

Research Collection School Of Computing and Information Systems

The Third Workshop on Social Media (WSM2011) continues the series of Workshops on Social Media in 2009 and 2010 and has been established as a platform for the presentation and discussion of the latest, key research issues in social media analysis, exploration, search, mining, and emerging new social media applications. It is held in conjunction with the ACM International Multimedia Conference (MM'11) at Scottsdale, Arizona, USA, 2011 and has attracted contributions on various aspects of social media including data mining from social media, content organization, geo-localization, personalization, recommendation systems, user experience, machine learning and social media approaches and architectures for …

An Effective Approach For Topicspecific Opinion Summarization, Binyang Li, Lanjun Zhou, Wei Gao, Kam-Fai Wong, Zhongyu Wei

Research Collection School Of Computing and Information Systems

Topic-specific opinion summarization (TOS) plays an important role in helping users digest online opinions, which targets to extract a summary of opinion expressions specified by a query, i.e. topic-specific opinionated information (TOI). A fundamental problem in TOS is how to effectively represent the TOI of an opinion so that salient opinions can be summarized to meet user’s preference. Existing approaches for TOS are either limited by the mismatch between topic-specific information and its corresponding opinionated information or lack of ability to measure opinionated information associated with different topics, which in turn affect the performance seriously. In this paper, we represent …

From Primordial Soup To Platform-Based Competition: Exploring The Emergence Of Products, Systems, And Platforms, C. Jason Woodard, Eric K. Clemons

Research Collection School Of Computing and Information Systems

We use an agent-based NK model to explore the conditions under which standard platforms emerge among competing products. Our findings were inconclusive. We find that the usual Darwinian conditions needed for the emergence of complexity are sufficient to yield a limited reliance upon platforms with a core of common components, simply because evolution causes the population to converge on a set of products that contain combinations that "work well," yielding what we call "coincidental platform emergence." Economies of scale yield more use of common components, or "production platform emergence." Positive participation externalities initially induce the highest degree of platform emergence …

Capir: Collaborative Action Planning With Intention Recognition, Nguyen T., Hsu D., Lee W., Tze-Yun Leong, Kaelbling L., Lozano-Perez T., Grant A.

Research Collection School Of Computing and Information Systems

We apply decision theoretic techniques to construct nonplayer characters that are able to assist a human player in collaborative games. The method is based on solving Markov decision processes, which can be difficult when the game state is described by many variables. To scale to more complex games, the method allows decomposition of a game task into subtasks, each of which can be modelled by a Markov decision process. Intention recognition is used to infer the subtask that the human is currently performing, allowing the helper to assist the human in performing the correct task. Experiments show that the method …

Discussion Of "Biomedical Ontologies: Toward Scientific Debate", Brochhausen M., Burgun A., Ceusters W., Hasman A., Tze-Yun Leong, Musen M., Oliveira J., Peleg M., Rector A., Schulz S.

Research Collection School Of Computing and Information Systems

With these comments on the paper “Biomedical Ontologies: Toward scientific debate”, written by Victor Maojo et al., Methods of Information in Medicine wants to stimulate a discussion on advantages and challenges of biomedical ontologies. An international group of experts have been invited by the editor of Methods to comment on this paper. Each of the invited commentaries forms one section of this paper.

Tracking Web Video Topics: Discovery, Visualization, And Monitoring, Juan Cao, Chong-Wah Ngo, Yong-Dong Zhang, Jin-Tao Li

Research Collection School Of Computing and Information Systems

Despite the massive growth of web-shared videos in Internet, efficient organization and monitoring of videos remains a practical challenge. While nowadays broadcasting channels are keen to monitor online events, identifying topics of interest from huge volume of user uploaded videos and giving recommendation to emerging topics are by no means easy. Specifically, such process involves discovering of new topic, visualization of the topic content, and incremental monitoring of topic evolution. This paper studies the problem from three aspects. First, given a large set of videos collected over months, an efficient algorithm based on salient trajectory extraction on a topic evolution …

Galaxy Browser: Exploratory Search Of Web Videos, Lei Pang, Song Tan, Hung-Khoon Tan, Chong-Wah Ngo

Research Collection School Of Computing and Information Systems

Most search engines return a ranked list of items in response to a query. The list however tells very little about the relationship among items. For videos especially, users often read to spend significant amount of time to navigate the search result. Exploratory search presents a new paradigm for browsing where the browser takes up the role of information exploring and presents a well-organized browsing structure for users to navigate. The proposed interface Galaxy Browser adopts the recent advances in near-duplicate detection and then synchronizes the detected near-duplicate information with comprehensive background knowledge derived from online external resources. The result …

Determination Of Sin2Θeff W Using Jet Charge Measurements In Hadronic Z Decays, D. Buskulic, M. Thulasidas

Research Collection School Of Computing and Information Systems

The electroweak mixing angle is determined with high precision from measurements of the mean dierence between forward and backward hemisphere charges in hadronic decays of the Z. A data sample of 2:5 million hadronic Z decays recorded over the period 1990 to 1994 in the ALEPH detector at LEP is used. The mean charge separation between event hemispheres containing the original quark and antiquark is measured for b b and cc events in subsamples selected by their long lifetimes or using fast D 's. The corresponding average charge separation for light quarks is measured in an inclusive sample from the …

Four-Jet Final State Production In E+E- Collisions At Centre-Of-Mass Energies Of 130 And 136 Gev, D. Buskulic, M. Thulasidas

Research Collection School Of Computing and Information Systems

The four-jet final state is analyzed to search for hadronic decays of pair-produced heavy particles. The analysis uses the ALEPH data collected at LEP in November 1995 at centre-of-mass energies of 130 and 136 GeV, corresponding to a total integrated luminosity of 5.7 pb1 . An excess of four-jet events is observed with respect to the standard model predictions. In addition, these events exhibit an enhancement in the sum of the two di-jet masses around 105 GeV/c 2 . The properties of these events are studied and compared to the expectations from standard processes and to pair production hypotheses

Content Contribution Under Revenue Sharing And Reputation Concern In Social Media: The Case Of Youtube, Qian Tang, Bin Gu, Andrew B. Whinston

Research Collection School Of Computing and Information Systems

A key feature of social media is that it allows individuals and businesses to contribute contents for public viewing. However, little is known about how content providers derive payoffs from such activities. In this study, we build a dynamic structural model to recover the utility function for content providers. Our model distinguishes short-term payoffs based on ad revenue sharing from long-term payoffs driven by content providers’ reputation. The model was estimated using a panel data of 914 top 1000 providers and 381 randomly selected providers on YouTube from Jun 7th, 2010, to Aug 7th, 2011. The two different sets of …

Sire: A Social Image Retrieval Engine, Steven C. H. Hoi, Pengcheng Wu

Research Collection School Of Computing and Information Systems

With the explosive growth of social media applications on the internet, billions of social images have been made available in many social media web sites nowadays. This has presented an open challenge of web-scale social image search. Unlike existing commercial web search engines that often adopt text based retrieval, in this demo, we present a novel web-based multimodal paradigm for large-scale social image retrieval, termed "Social Image Retrieval Engine" (SIRE), which effectively exploits both textual and visual contents to narrow down the semantic gap between high-level concepts and low-level visual features. A relevance feedback mechanism is also equipped to learn …

Case Study On Using A Programming Practice Tool For Evaluating University Applicants, Shannon Christopher Boesch, Kevin Steppe

Research Collection School Of Computing and Information Systems

We used a programming practice tool to test basic programming skills of prospective students. A live competition was used to test those skills. Students who did well were asked for further interviews. Most students had no prior background and reported learning the basics of two programming languages within two weeks of self-study.

On Two Rfid Privacy Notions And Their Relations, Yingjiu Li, Robert H. Deng, Junzuo Lai, Changshe Ma

Research Collection School Of Computing and Information Systems

Privacy of RFID systems is receiving increasing attention in the RFID community. Basically, there are two kinds of RFID privacy notions in the literature: one based on the indistinguishability of two tags, denoted as ind-privacy, and the other based on the unpredictability of the output of an RFID protocol, denoted as unp*-privacy. In this article, we first revisit the existing unpredictability-based RFID privacy models and point out their limitations. We then propose a new RFID privacy model, denoted as unp*-privacy, based on the indistinguishability of a real tag and a virtual tag. We formally clarify its relationship with the ind-privacy …

Evolving Law And Policy For Freshwater Ecosystem Service Markets, Martin W. Doyle, Todd Bendor

William & Mary Environmental Law and Policy Review

No abstract provided.

Mineralogical, Petrographical And Geochemical Characteristics Of Eldivan Ophiolite (Çankiri) Harzburgitic Tectonites, Tijen Üner, Üner Çakir

Bulletin of the Mineral Research and Exploration

The Eldivan Ophiolite is located at the central part of the Ýzmir-Ankara-Erzincan Ophiolitic Belt and between Þabanözü, Eldivan and Korgun towns. Ophiolite consists of volcanic-sedimentary series, metamorphic series, tectonites, cumulates and sheeted dikes from bottom to top. Tectonites, which are the main subject of the study, are generally represented by harzburgites and occassionally include dunite, pyroxenolite and chromitite levels. Harzburgites display of traces of plastic deformation (foliation, lineasyon, fold) A clear orientation in minerals can be observed as a result of in the tectonic sequence and grinding mechanisms. The degree of deformation decreases upwards. Harzburgites are generally composed of olivine …

Adhesion And Durability Of Coatings On Polypropylene Exterior Sidings, Logan Riekio Stark

Master's Theses

Plastics have become a universal material for use in a myriad of commercial and consumer products. One such product, exterior siding, is the focus of this project. Although siding products were originally made from wood, vinyl siding, which offered superior performance, was introduced in the 1950’s. More recently, polypropylene (PP) siding has been introduced; PP provides a stronger product, which allows for deeper patterns and better edge detailing. PP siding, compared to traditional wood siding, doesn’t warp, crack, or degrade as easily with extended exposure to the elements, and is cheaper to maintain. However, even plastic siding must be coated. …

What's Up, Weelic?: Tracking Neural Pathways With A Sugar-Coated Virus, Weelic Chong

The Synapse: Intercollegiate science magazine

No abstract provided.

Going Green, Dermot Kehily

Articles

No abstract provided.

Design And Implementation Of An Open Framework For Ubiquitous Carbon Footprint Calculator Applications, Farzana Rahman, Casey O'Brien, Sheikh Iqbal Ahamed, He Zhang, Lin Liu

Mathematics, Statistics and Computer Science Faculty Research and Publications

As climate change is becoming an important global issue, more and more people are beginning to pay attention to reducing greenhouse gas emissions. To measure personal or household carbon dioxide emission, there are already plenty of carbon footprint calculators available on the web. Most of these calculators use quantitative models to estimate carbon emission caused by a user's activities. Although these calculators can promote public awareness regarding carbon emission due to an individual's behavior, there are concerns about the consistency and transparency of these existing CO₂ calculators. Apart from a small group of smart phone based carbon footprint calculator …

Water Quality Models For Stormwater Runoff In Two Lincoln, Nebraska Urban Watersheds, Jake Fisher

Department of Civil and Environmental Engineering: Dissertations, Theses, and Student Research

Water quality monitoring was conducted in two urban watersheds (Colonial Hills and Taylor Park) located in southeast Lincoln, NE over a three year period spanning from October 2008 through September 2011. In-line probes continuously measured for turbidity, conductivity, dissolved oxygen, and water temperature while other water quality constituents were analyzed for discrete water samples collected using grab and automatic sampling techniques. The water quality data was used to calculate event mean concentrations (EMCs) for sixteen storm events sampled over the duration of the project period. Three types of stormwater quality multiple linear regression models were developed for the estimation of …

Analyzing Common Algebra-Related Misconceptions And Errors Of Middle School Students., Sarah B. Bush

Electronic Theses and Dissertations

The purpose of this study was to examine common algebra-related misconceptions and errors of middle school students. In recent years, success in Algebra I is often considered the mathematics gateway to graduation from high school and success beyond. Therefore, preparation for algebra in the middle grades is essential to student success in Algebra I and high school. This study examines the following research question: What common algebra-related misconceptions and errors exist among students in grades six and eight as identified on student responses on an annual statewide standardized assessment? In this study, qualitative document analysis of existing data was used …

A Web-Integrated Environment For Component-Based Software Reasoning, Charles Cook

All Theses

This thesis presents the Web IDE, a web-integrated environment for component-based software reasoning. The Web IDE is specifically tailored to emphasize the relationships among various components in component-based software engineering (CBSE) and to facilitate reasoning. It allows students to use RESOLVE, a component-based, integrated specification and programming language, to build components and systems, providing real-time feedback that can be used to reason about the correctness of their component implementations. Real-time interaction and relationship focused component presentation reinforces CBSE and reasoning principles in a way not possible with traditional programming exercises and file management systems.
The Web IDE has gone through …