Physical Sciences and Mathematics Commons^™

Efficient Estimation Of Cluster Population, Sanjeev K C

UNLV Theses, Dissertations, Professional Papers, and Capstones

Partitioning a given set of points into clusters is a well known problem in pattern recognition, data mining, and knowledge discovery. One of the well known methods for identifying clusters in Euclidean space is the K-mean algorithm. In using the K-mean clustering algorithm it is necessary to know the value of k (the number of clusters) in advance. We propose to develop algorithms for good estimation of k for points distributed in two dimensions. The techniques we pursue include a bucketing method, g-hop neighbors, and Voronoi diagrams. We also present experimental results for examining the performances of the bucketing method …

Exact Statistical Inferences For Functions Of Parameters Of The Log-Gamma Distribution, Joseph F. Mcdonald

UNLV Theses, Dissertations, Professional Papers, and Capstones

The log-gamma model has been used extensively for flood frequency analysis and is an important distribution in reliability, medical and other areas of lifetime testing. Conventional methods fails to provide exact solutions for the log-gamma model while asymptotic methods provide approximate solutions that often have poor performance for typical sample sizes. The two parameter log-gamma distribution is examined using the generalized p-value approach. The methods are exact in the sense that the tests and the confidence intervals are based on exact probability statements rather than on asymptotic approximations. Exact tests and exact confidence intervals for the parameter of interest based …

Generalized Markoff Equations, Euclid Trees, And Chebyshev Polynomials, Donald Joseph Mcginn

UNLV Theses, Dissertations, Professional Papers, and Capstones

The Markoff equation is x^2+y^2+z^2 = 3xyz, and all of the positive integer solutions

of this equation occur on one tree generated from (1, 1, 1), which is called the

Markoff tree. In this paper, we consider trees of solutions to equations of the form

x^2 + y^2 + z^2 = xyz + A. We say a tree of solutions satisfies the unicity condition

if the maximum element of an ordered triple in the tree uniquely determines the

other two. The unicity conjecture says that the Markoff tree satisifies the unicity

condition. In this paper, we show that there exists …

Situational Assessment Using Graph Comparison, Pavan Kumar Pallapunidi

UNLV Theses, Dissertations, Professional Papers, and Capstones

In strategic operations, the assessment of any given situation is very important and may trigger the development of a mission plan. The mission plan consists of various actions that should be executed in order to successfully mitigate the situation. For a new mission plan to be designed or implemented, the effect of the previous mission plan should be accessed. These mission plans use various sensors to collect the data which can be very large and aggregate them to obtain detailed information of the situation. In order to implement an effective mission plan the current situation has to be assessed effectively. …

A Multi-Level Trust Management Scheme For The Internet Of Things, Anusha Ramanathan

UNLV Theses, Dissertations, Professional Papers, and Capstones

The significance of the Internet of Things (IoT) in current trends is continuously rising. It is an umbrella term that signifies a network of physical devices that are embedded with electronics, software, sensors and connectivity that enable greater functions and services through the exchange of data accomplished through interconnection. The applications of the IoT are varied and numerous; they range from relatively simple home automation scenarios to the much more complex scenarios of interconnected smart cities. IoT is expected to dominate the future with huge amounts of content oriented traffic that is a result of intensive interactions between the millions …

Concurrent Non-Blocking Skip List Using Multi-Word Compare And Swap Operation, Anish Ratna Tuladhar

UNLV Theses, Dissertations, Professional Papers, and Capstones

We present a non-blocking lock-free implementation of skip list data structure using multi word compare and swap (CASN) operation. This operation is designed to work on arbitrary number of memory locations as a single atomic step. We discuss the implementation details of CASN operation which only utilizes the single word compare and swap atomic primitive found in most of the contemporary multiprocessor systems. Using this operation, we first design lock-free algorithms to implement various operations on linked list data structure, then extend it to design skip lists. Skip list is a probabilistic data structure composed of linked lists stacked together …

Carbon Isotope Variations Associated With A Middle Ordovician Karstic Unconformity, Patricia Suzanne Williams

UNLV Theses, Dissertations, Professional Papers, and Capstones

Large negative carbon isotope (δ¹³C) excursions have been documented from late Neoproterozoic-Paleozoic successions. These δ¹³C excursions have been widely used for regional and global stratigraphic correlation, particularly in strata with limited paleontological and radiometric age controls. Recent studies, however, argued that some negative δ¹³C excursions from stratigraphic record may have been resulted from meteoric/burial diagenesis, which commonly shifts both carbon and oxygen isotopes toward lower values. Testing the diagenetic origin of δ¹³C excursions in stratigraphic successions without independent stratigraphic framework has been difficult because it evolves into circular arguments about stratigraphic completeness …

Framing Reality: Portrayals Of Climate Change In The "Las Vegas Review-Journal", 1997-2014, Jason Ryan Holley

UNLV Theses, Dissertations, Professional Papers, and Capstones

Discussions of human-caused climate change have become an increasingly salient artifact of various media in recent years. With regard to print media in particular, scholars have uncovered general increases in the frequencies with which climate change articles are published, tantamount to the annual reports from the Intergovernmental Panel on Climate Change (IPCC) advocating the detriments of human activities (particularly carbon dioxide emissions) on the natural environment. Among such reports—be they scientific or anecdotal—writers and journalists have had to interpret the ongoing discussions and evidence surrounding climate change, and develop schemas (or frames) in which to situate arguments. These arguments have …

A Study Of Sequential Inference For The Risk Ratio And Measure Of Reduction Of Two Binomials, Zhou Wang

UNLV Theses, Dissertations, Professional Papers, and Capstones

The binomial distribution is one of the most commonly and widely occurring probabilistic phenomena in our lives. Since observations from independent Bernoulli trials yield a dichotomous type, the distribution of sequences provides the basis and clue for statistical formulations of a wide variety of problems.

Occasionally, the core of biomedical studies is related to the comparison and evaluation of the risks of events or outcomes of interest in comparing populations under study. For instance, one wishes to compare two groups of subjects drawn from two independent populations. Then, two sample proportions play central roles in those comparisons. One of the …

Parameters Identification For A Composite Piezoelectric Actuator Dynamics, Mohammad Saadeh, Mohamed Trabia

Mechanical Engineering Faculty Research

This work presents an approach for identifying the model of a composite piezoelectric (PZT) bimorph actuator dynamics, with the objective of creating a robust model that can be used under various operating conditions. This actuator exhibits nonlinear behavior that can be described using backlash and hysteresis. A linear dynamic model with a damping matrix that incorporates the Bouc–Wen hysteresis model and the backlash operators is developed. This work proposes identifying the actuator’s model parameters using the hybrid master-slave genetic algorithm neural network (HGANN). In this algorithm, the neural network exploits the ability of the genetic algorithm to search globally to …

Climate Change, Disasters & Displacement, Elizabeth Ferris

Brookings Scholar Lecture Series

This lecture examines trends in natural disasters, the effects of climate change, and their impact on human rights, including economic costs, the displacement/migration of people, and the likelihood that the poor and marginalized are most likely to be affected by natural disasters and climate change.

Mcnair Research Journal - Summer 2015, Kelly Abuali, Starr Bailey, Krystal Courtney D. Belmonte, Brittaney Benson-Townsend, Jennifer Bolick, Mihaela A. Ciulei, Ashley Crisp, Daniel N. Erosa, Richard V. Foster, Gisele Braga Goertz, Michael A. Langhardt, Kara Osborne, Julienne Jochel Paraiso, Shawn M. Rosen, Bella V. Smith, Jeevake Attapattu, Ernesto H. Bedoy, Michael G. Curtis, Wanda Inthavong, Marielle Leo, Primrose Martin, Tamieka Meadows, Rosa Perez, Jessica Recarey, Shea Silver, Linda Tompkins

McNair Journal

Journal articles based on research conducted by undergraduate students in the McNair Scholars Program

Table of Contents

Biography of Dr. Ronald E. McNair

Statements:

Dr. Neal J. Smatresk, UNLV President

Dr. Juanita P. Fain, Vice President of Student Affairs

Dr. William W. Sullivan, Associate Vice President for Retention and Outreach

Mr. Keith Rogers, Deputy Executive Director of the Center for Academic Enrichment and Outreach

McNair Scholars Institute Staff

Propagation Of Lightning Through Thick Thunderclouds, Isaiah Henry, Dieudonné D. Phanord

McNair Poster Presentations

The phenomenon that is lightning, have sparked the interest of physicists and scientists for centuries. The journey to understanding this phenomenon of high-current electric discharge, can unlock the secret to other lightning related phenomenons. Lightning is a major source of interference in many types of radio communications. The effects of lightning on space crafts, nuclear power plants, and sophisticated military equipment, are problems of increasing concern. The purpose of this research is to study the propagation of lightning through optically thick thunderclouds by applying knowledge of cloud micro-physics, the physics of lightning, diffusion approximations, and an understanding of the scattering …

Study Of Cuinte2 Quantum Dots Under Extreme Conditions, Howard Yanxon, Ravhi Kumar

McNair Poster Presentations

In recent years, Quantum Dot (QD) materials have attracted considerable interest due to their versatile properties and potential applications in electronics, biology, and optoelectronics, i.e. photovoltaic solar cell materials [1-2].

In 2000, RincÓn et al. reported an extensive study of the bulk material of CuInTe₂ along with its comparison to its ordered defect compounds [3]. The chalcopyrite structure consists of eight atoms per unit cell. This means there are 24 vibrational modes expected for the tetragonal structure. Out of the 24 modes, 21 vibrational modes belong to optical modes, and the other 3 modes are acoustical modes. The irreducible …

College Of Engineering Senior Design Competition Fall 2014, University Of Nevada, Las Vegas

Fred and Harriet Cox Senior Design Competition Projects

Part of every UNLV engineering student’s academic experience, the senior design project stimulates engineering innovation and entrepreneurship. Each student in their senior year chooses, plans, designs, and prototypes a product in this required element of the curriculum. A capstone to the student’s educational career, the senior design project encourages the student to use everything learned in the engineering program to create a practical, real world solution to an engineering challenge. The senior design competition helps focus the senior students in increasing the quality and potential for commercial application for their design projects. Judges from local industry evaluate the projects on …

Spectroscopic Investigation Of The Chemical And Electronic Properties Of Chalcogenide Materials For Thin-Film Optoelectronic Devices, Kimberly Horsley

UNLV Theses, Dissertations, Professional Papers, and Capstones

Chalcogen-based materials are at the forefront of technologies for sustainable energy production. This progress has come only from decades of research, and further investigation is needed to continue improvement of these materials.

For this dissertation, a number of chalcogenide systems were studied, which have applications in optoelectronic devices, such as LEDs and Photovoltaics. The systems studied include Cu(In,Ga)Se2 (CIGSe) and CuInSe2 (CISe) thin-film absorbers, CdTe-based photovoltaic structures, and CdTe-ZnO nanocomposite materials. For each project, a sample set was prepared through collaboration with outside institutions, and a suite of spectroscopy techniques was employed to answer specific questions about the system. These …

Empirical Studies On Interest Rate Derivatives, Xudong Sun

UNLV Theses, Dissertations, Professional Papers, and Capstones

Interest rate models are the building blocks of financial market and the interest rate derivatives market is the largest derivatives market in the world. In this dissertation, we shall focus on numerical pricing of interest rate derivatives, estimating model parameters by Kalman filter, and studying various models empirically. We shall propose a front-fixing finite element method to price the American put option under the quadratic term structure framework and compare it with a trinomial tree method and common finite element method. Numerical test results show the superiority of our front-fixing finite element method in the aspects of computing the option …

Estimating Aquifer Characteristics And Identification Of A Sub-Basin For Artificial Storage And Recovery, Northeastern Ivanpah Valley, Nevada, Nikolas James Taranik

UNLV Theses, Dissertations, Professional Papers, and Capstones

The identification of a structurally controlled sub-basin with impediments to groundwater flow within Southern Nevada could provide a favorable area for artificial recharge and storage of native or imported water, extending the water supply of Southern Nevada. For this purpose, the area of northeastern Ivanpah Valley was investigated to determine the ability of the aquifer to accept and recover stored water, if acceptable water quality existed in the potential sub-basin storage area, and if structural controls impeded and isolated groundwater flow. The results found evidence the proposed sub-basin is structurally isolated by the McCullough, Roach, and Stateline Faults, which was …

Gis Framework For Spatiotemporal Mapping Of Urban Flooding And Analyze Watershed Hydrological Response To Land Cover Change, Sayed Joinal Hossain Abedin

UNLV Theses, Dissertations, Professional Papers, and Capstones

Urban flooding is a manmade disaster, and a recurrent problem in cities around the globe. Increased surface imperviousness due to urbanization along with inadequate drainage infrastructure system are the chief culprits for urban flooding. Flooding in an urban area brings about severe economic, structural, and environmental damages, and can be associated with casualties too. In order to evade flooding, an efficient flood model is imperative to study current flooding, and analyze flooding behavior to urban surface characteristics.

This research aims to develop a framework using Geographic Information System (GIS) to perform modeling and mapping of flood spatiotemporal variation in urban …

Simultaneous Determination Of Multiple Actinide Elements In A Variety Of Soils Utilizing A Standardized Sequential Extraction Protocol, Sherry Alina Faye

UNLV Theses, Dissertations, Professional Papers, and Capstones

To obtain a better understanding of the mobility of actinide element contaminants in the environment, the association of the contaminants with specific host phases of soils and sediments must be investigated. This investigation is most commonly conducted using sequential extraction techniques that employ the selective dissolution of soil phases with increasingly aggressive chemical treatment. Though several sequential extraction studies exist in literature, conclusions cannot be made by direct comparison of data due to the lack of uniformity in the protocols used. This work aims to continue development of a standard sequential extraction protocol and expanding its capabilities to include the …

Global Climate Change: The Political Impact Of Global Warming On Developing Countries. The Case Studies Of Egypt And Oman, Eugene Thomas O'Neal

UNLV Theses, Dissertations, Professional Papers, and Capstones

The discourse of climate change has become important in the field of political science, as well as in the policy-making community. Climate change has become a political phenomenon that has and will greatly impact political stability regionally and globally. Using the ecological security theory as a framework, I explored the relationship between climate change and political stability in developing countries.

This study utilizes both qualitative and quantitative analyses to investigate the relationship between climate change and its effects on political volatility in developing countries. Using regression models, the author examined all non-OECD countries (140 countries) and their relationship to political …

Identification Of Long Term Changes And Evaluation Of The Relationships Among Streamflow Variability And Oceanic-Atmospheric Indices, Soumya Sagarika

UNLV Theses, Dissertations, Professional Papers, and Capstones

To examine the effects of climate variability on streamflow, this thesis presents a comprehensive analysis of the streamflow variability of the continental United States and its association with oceanic-atmospheric indices. First, the presence of trends with consideration of short term and long term persistence followed by shifts over the past years in the continental U.S. streamflow were analyzed by using the non-parametric tests: Mann Kendall and Pettitt. Second, the spatio-temporal relationships between seasonal streamflow variability of continental U.S. and sea surface temperatures (SST) and 500 mbar geopotential height (Z500) of the Pacific and Atlantic were established using the singular valued …

Thermal Impacts Of Salt On Sandstones And Mudstones In The Lusitanian Basin, Portugal, Brett Perry

UNLV Theses, Dissertations, Professional Papers, and Capstones

In order to assess the impact of salt structures on paleotemperatures in adjacent sedimentary rocks, a field based study which quantified thermally driven diagenetic products as a function of distance from salt was undertaken. Several salt diapirs are now exposed at the surface of the Earth within the Lusitanian Basin and offered a unique opportunity to document paleothermal anomalies by studying thermally controlled diagenesis in adjacent, exposed Upper Jurassic rocks. Four transects were chosen within Upper Jurassic rocks that contained both sandstones and mudstones. Quartz cementation and albitization of feldspars, both of which are thermally driven processes, were quantified in …

Exact Controllability Of The Lazer-Mckenna Suspension Bridge Equation, Lanxuan Yu

UNLV Theses, Dissertations, Professional Papers, and Capstones

It is well known that suspension bridges may display certain oscillations under external aerodynamic forces. Since the collapse of the Tacoma Narrows suspension bridge in 1940, suspension bridge models have been studied by many researchers. Based upon the fundamental nonlinearity in suspension bridges that the stays connecting the supporting cables and the roadbed resist expansion, but do not resist compression, new models describing oscillations in suspension bridges have been developed by Lazer and McKenna [Lazer and McKenna (1990)]. Except for a paper by Leiva [Leiva (2005)], there have been very few work on controls of the Lazer-McKenna suspension bridge models …

Decontamination Protocols For Watercraft And Wildland Firefighting Equipment In Preventing The Spread Of Invasive Quagga (Dreissena Rostriformis Bugensis) And Zebra (Dreissena Polymorpha) Mussels, Ashlie Watters

UNLV Theses, Dissertations, Professional Papers, and Capstones

Quagga and zebra mussels (Dreissena rostriformis bugensis and Dreissena polymorpha) are two invasive species introduced via ballast water discharged by large oceanic cargo ships to the North American Great Lakes in the late 1980s. Once established, the mussels spread quickly. In January 2007, D. rostriformis bugensis was discovered in Lake Mead, NV-AZ, and in that same year, mussels were confirmed further south on the Colorado River in Lakes Mojave and Havasu. Dreissenids clog water intake pipes, water filtration systems, and electric generating plants. The mussels also ruin boat motors, damage recreational equipment, and once established in the reservoir, routine maintenance …

A Study Of Graphical Permutations, Jessica Thune

UNLV Theses, Dissertations, Professional Papers, and Capstones

A permutation π on a set of positive integers {a_1,a_2,...,a_n} is said to be graphical if there exists a graph containing exactly a_i vertices of degree (a_i) for each i. It has been shown that for positive integers with a_1

Modeling And Analysis Of Pedestrian Flows, Romesh Khaddar

UNLV Theses, Dissertations, Professional Papers, and Capstones

According to the Traveler Opinion and Perception Survey of 2005, about 107.4 million Americans regularly use walking as a mode of transport during their commute, which amounts for 51% of the total American population. In 2009, 4092 pedestrian fatalities were reported nationwide, out of 59,000 pedestrian crashes. This amounts for 12% of the fatalities in the total traffic accidents recorded, and shows an over-representation of pedestrians incidents. Thus, it is imperative to understand the causes behind such statistics, and conduct a comprehensive research on pedestrian walking behavior and their interaction with surroundings.

A lot of researches on pedestrian flows have …

Design And Implementation Of An Instruction Set Architecture And An Instruction Execution Unit For The Rez9 Coprocessor System, Daniel Spencer Anderson

UNLV Theses, Dissertations, Professional Papers, and Capstones

While the use of RNS has provided groundbreaking theory and progress in this field, the applications still lack viable testing platforms to test and verify the theory. This Thesis outlines the processing of developing an instruction set architecture (ISA) and an instruction execution unit (IEU) to help make the first residue based general processor a viable testing platform to address the mentioned problems.

Consider a 32-bit ripple adder. The delay on this device will be 32N where N is the delay for each adder to complete its operation. The delay of this process is due to the need to propagate …

Technetium Sulfide: Fundamental Chemistry For Waste Storage Form's Application, Maryline Ghislaine Ferrier

UNLV Theses, Dissertations, Professional Papers, and Capstones

Technetium is the lightest radioelement. The isotope ⁹⁹Tc has around a 6% yield from ²³⁵U with a half-life of 2.13 x 10⁵ years. The high mobility of TcO₄^-, the common chemical form of technetium in the environment makes ⁹⁹Tc an isotope of concern in nuclear waste management. Despite its important role in radiopharmaceuticals and in the nuclear fuel cycle, the fundamental chemistry of technetium is not as well developed as that of the neighboring transition metals; one of the most striking examples being its sulfide chemistry.

Only two technetium binary sulfide compounds had …

Keeping In Touch: Exchange As An Adaptive Strategy In Southern Nevada, Timothy Joshua Ferguson

UNLV Theses, Dissertations, Professional Papers, and Capstones

Archaeologists have always wondered about the extent of vessel movement in the American Southwest. Identifying vessel movement allows for the study of social interactions across a region and the role of ceramics in the adaptive processes of agriculturalists living in marginal, highly variable environments. In many instances, exchange may act as a way to reduce the risk of resource shortfalls by creating social ties in other areas. This research investigated the changing risk reduction strategies of households in the lowland Virgin region of southern Nevada by using geochemical methods to trace the exchange of locally produced pottery. It was hypothesized …