Physical Sciences and Mathematics Commons^™

The Use Of Tilt Angle In Gravity And Magnetic Methods, Uğur Akin, Betül Işikdeni̇z Şeri̇foğlu, Mehmet Duru

Bulletin of the Mineral Research and Exploration

Tilt angle method, which has been recently used in investigating the boundaries of structures, reveals useful information on deep and shallow structures. Tilt angle is expressed as the arctan value of the ratio of the vertical derivative of the potential field to its horizontal derivative. The method was applied to Kýrþehir-Ý31 Sheet. As a result, the presence of volcanites buried under terrestrial sediments was demonstrated.

The Tectonostratigraphic Features Of The Belemedi̇k Tectonic Window And Its Surroundings, İsmet Alan, Şenol Şahi̇n, Alican Kop, Bülent Bakirhan, Nevzat Böke

Bulletin of the Mineral Research and Exploration

The study area includes Belemedik and its vicinity located in the eastern part of Ecemiþ Fault Zone which constitutes the boundary between Central and Eastern Taurides.The area generally presents Belemedik Sequence belonging to Aladað Unit, Ophiolithic Melange and ophiolithic rocks belonging to Bozkýr Unit and Tertiary sediments overlying all these units. Within Belemedik Sequence, Late Devonian aged Küçükali, Carboniferous aged Belemedik, Early Permian aged Sarýoluk, Late Permian aged Kýzýlgeriþ and Yellice, EarlyMiddle Triassic aged Katarasý, Middle-Late Triassic aged Sarýyarma, Jurassic-Cretaceous aged Çamlýk and Yavça Formations were differentiated. In the previous studies on the vicinity of Belemedik, it was suggested that …

Electrochemistry Of Pani/Metal Composites In Basic Solutions, Tamthinhan Quy

UNLV Theses, Dissertations, Professional Papers, and Capstones

Polyaniline (PANI) has been extensively investigated due to its unique conductivity, which is primarily dependent on the oxidation state of the material and the solution pH. PANI is an insulator when it is oxidized, and the solution pH exceeds four. Numerous attempts to extend PANI's conductivity to neutral and alkaline environments have been unsuccessful. However, our previous study has demonstrated that PANI/Pd composite is conductive and catalytically active in a basic solution, pH ∼ 12. Therefore, the conductivity and the electrochemical properties of PANI composites including PANI/Au, PANI/Pd and PANI/Pt were evaluated in basic solutions. The fundamental studies of PANI/metal …

Gendered Livelihoods And The Politics Of Socio-Environmental Identity: Women’S Participation In Conservation Projects In Calakmul, Mexico, Claudia Radel

Environment and Society Faculty Publications

A livelihoods approach positions individuals, situated within households, as active agents within processes occurring at various scales. Environmental conservation efforts represent one such process with direct implications for local sustainable livelihoods and the gendered nature of livelihood strategies. In this article, I examine collective processes of socio-environmental identity construction as gendered sustainable livelihood strategies, articulated in and through the activities of women's agricultural organizations in communities bordering the Calakmul Biosphere Reserve in rural southern Mexico. I present group histories and visual evidence from group activities – adapted from participatory rural appraisal (PRA) methodology – to highlight two important concepts. These …

Opacity Of P(Mma-Maa)-Pmma Composite Latex System With Varying Maa Concentration, Gilbert U. Yu, Jerry T. Dy, Erwin P. Enriquez

Chemistry Faculty Publications

Polymer composites of core-shell morphology are commonly used in the paint industry as opacity enhancer. These are usually made of block copolymer systems wherein the core is formed from a polymer that swells in the presence of a solvent and surrounded by a high glass transition polymeric shell. Thus, upon drying, the swollen regions turn into voids while leaving a hard shell. Here, composites based on poly(methyl methacrylate-butyl acrylate) [P(MMA-BuA)] (seed stage), poly(methyl methacrylate-methacrylic acid) [P(MMA-MAA)] (second stage), and poly(methyl methacrylate) [PMMA] (third stage) were synthesized through a multistage sequential emulsion polymerization and their opacity was investigated. The second stage …

Mahalanobis-Taguchi System As A Multi-Sensor Based Decision Making Prognostics Tool For Centrifugal Pump Failures, Ahmet Soylemezoglu, Sarangapani Jagannathan, Can Saygin

Electrical and Computer Engineering Faculty Research & Creative Works

A novel Mahalanobis Taguchi System (MTS) based fault detection, isolation, and prognostics scheme is presented. the proposed scheme fuses data from multiple sensors into a single system level performance metric using Mahalanobis Distance (MD) and generates fault clusters based on MD values. MD thresholds derived from the clustering analysis are used for fault detection and isolation. When a fault is detected, the prognostics scheme, which monitors the progression of the MD values over time, is initiated. Then, using a linear approximation, time to failure is estimated. the performance of the scheme has been validated via experiments performed on a mono-block …

Observations Of The Vertical Ion Drift In The Equatorial Ionosphere During The Solar Minimum Period Of 2009, R. A. Stoneback, R. A. Heelis, A. G. Burrell, W. R. Coley, Bela G. Fejer, E. Pacheco

Bela G. Fejer

[1] The extended solar minimum conditions in 2008 and 2009 presented an opportunity to investigate the ionosphere at lower solar activity levels than previously observed. The Coupled Ion Neutral Dynamics Investigation (CINDI) Ion Velocity Meter (IVM) instrument onboard the Communication/Navigation Outage Forecasting System is used to construct the median meridional (vertical) ion drifts, ion densities, and O+ concentrations during periods of low geomagnetic activity for four characteristic seasons each year spanning late 2008 to 2010. The presence of a large semidiurnal component in the ion drift variation at the equator produced significant differences from typical ionospheric conditions. Instead of upward …

Magma Chamber Processes At Mutnovsky Volcano, Russia, Kelly L. Robertson

UNLV Theses, Dissertations, Professional Papers, and Capstones

This dissertation is composed of two manuscripts about the evolution of Mutnovsky Volcano in Kamchatka, Russia. Mutnovsky has been active for the past approximately 80,000 years, during which there was the formation and subsequent eruption of four major stratocones. These four eruptive centers, named Mutnovsky I, II, III, and IV from oldest to youngest, have a range of erupted product compositions from basalt to dacite. The first major goal of this project was to investigate the melt source for Mutnovsky. Whole rock trace element and Nd, Sr, and Pb isotopic data were used to determine that the melt source was …

Development Of A Simulation Tool For Analysis Of Freeway Crashes Due To Cell Phone Usage, Sourabh Sriom

UNLV Theses, Dissertations, Professional Papers, and Capstones

Research shows that drivers are susceptible to numerous distractions while driving which can be held responsible as the reason of a crash. Usage of cell phones, i.e. talking or texting while driving is considered one of the prominent distractions which causes a crash. This dissertation aims to study the number of crashes occurring on the freeways and their relation with the drivers of these cars using cell phones while they are driving. Since crashes occur relatively less frequently, the study of crashes is done using what is called the "rare event" theory. Java based simulations are done to model a …

Concept Tests For A New Wire Flying Vehicle Designed To Achieve High Horizontal Resolution Profiling In Deep Water, Chris Roman, Dave Hebert

Graduate School of Oceanography Faculty Publications

Efficiently profiling the water column to achieve both high vertical and horizontal resolution from a moving vessel in deep water is difficult. Current solutions, such as CTD tow-yos, moving vessel profilers, and undulating tow bodies, are limited by ship speed or water depth. As a consequence, it is difficult to obtain oceanographic sections with sufficient resolution to identify many relevant scales over the deeper sections of the water column. This paper presents a new concept for a profiling vehicle that slides up and down a towed wire in a controlled manner using the lift created by wing foils. The wings …

Multicomponent Reactions For The Preparation Of Fluorous Taged Pyrimidines And Thiopyrimidines And Their Derivatisation To Obtain Biaryl-Substituted Heterocycles, Bruno Piqani

Graduate Masters Theses

This thesis presents a work in the field of multicomponent reactions (MCRs), one-step condensation between a fluorous tagged aldehyde, β-keto ester and urea derivatives. This process in literature is known as "Biginelli Reaction". This dissertation describes a new Biginelli reaction element, using fluorous component as a limiting agent.

Chapter one is an introduction of MCRs. A brief historical review, key principles as well as applications in different fields such as academic research, synthetic organic chemistry, and medicinal applications are presented.

Chapter two discusses the general features of the Biginelli reaction, microwave, and fluorous chemistry with a distinctive look from the …

Making An Impact On The Obesity Epidemic By Deploying A Mobile Fitness Suite On The Android Market, Chad Richards

Computer Science and Computer Engineering Undergraduate Honors Theses

The Mobile Fitness Suite aims to make an impact on the obesity epidemic by deploying a set of mobile fitness applications on the Android Market. The thesis details the health and financial issues with the obesity epidemic, along with its causes, and how a set of fitness applications can aid with the obesity epidemic. It also explains the reasons for releasing the program on the Android Market and details each step in the process of deploying a mobile application to the Android Market. Further, it discusses the design and architecture that went into the development of the Mobile Fitness Suite …

Ensemble Methods For Dynamic Data Assimilation Of Chemical Observations In Atmospheric Models, Adrian Sandu, Emil Constantinescu, Gregory R. Carmichael, Tianfeng Chai, Dacian Daescu, John H. Seinfeld

Mathematics and Statistics Faculty Publications and Presentations

The task of providing an optimal analysis of the state of the atmosphere requires the development of dynamic data-driven systems (DDDAS) that efficiently integrate the observational data and the models. Data assimilation, the dynamic incorporation of additional data into an executing application, is an essential DDDAS concept with wide applicability. In this paper we discuss practical aspects of nonlinear ensemble Kalman data assimilation applied to atmospheric chemical transport models. We highlight the challenges encountered in this approach such as filter divergence and spurious corrections, and propose solutions to overcome them, such as background covariance inflation and filter localization. The predictability …

Modeling Parental Provisioning By Red-Winged Blackbirds In North Dakota, George M. Linz, Richard S. Sawin, Mark W. Lutman, William J. Bleier

The Prairie Naturalist

Male red-winged blackbirds (Agelaius phoeniceus) exhibit a difference in nest provisioning rates along an east-west gradient in North America. North Dakota is located in the center of North America and harbors a large population of breeding red-winged blackbirds (RWBL). This location provided an opportunity to compare provisioning rates in the central U.S. with those reported for the eastern and western populations. We placed video cameras at RWBL nests to record male and female feeding trips. Thirty-four nests were located on territories with original males and 30 were on territories where a replacement (floater) male had taken over a …

Manuscript Content: Where Does It Belong?, Christopher N. Jacques

The Prairie Naturalist

One of the most common issues we address during content editing of papers for The Prairie Naturalist (journal) is the appropriate placement of content in the text body. Based on my experience with the editorial process, content placement also is one of the issues that authors are most resistant to suggestions or do not fully understand why we are so persistent about it (Thompson 2010). One of the primary objectives of scientific writing is to concisely and accurately disseminate information. Scientific papers are structured to help both the author and reader accomplish this objective. The material that belongs in each …

Edge-Guarding Orthogonal Polyhedra, Nadia M. Benbernou, Erik D. Demaine, Martin L. Demaine, Anastasia Kurdia, Joseph O'Rourke, Godfried Toussaint, Jorge Urrutia, Giovanni Viglietta

Computer Science: Faculty Publications

We address the question: How many edge guards are needed to guard an orthogonal polyhedron of e edges, r of which are reflex? It was previously established [3] that e/12 are sometimes necessary and e/6 always suf- fice. In contrast to the closed edge guards used for these bounds, we introduce a new model, open edge guards (excluding the endpoints of the edge), which we argue are in some sense more natural in this context. After quantifying the relationship between closed and open edge guards, we improve the upper bound to show that, asymptotically, (11/72)e (open or closed) edge guards …

A Secure And Distributed Framework To Identify And Share Needed Information, Wei Jiang, Bharath K. Samanthula

Computer Science Faculty Research & Creative Works

Information analysis and communication play significant roles in decision making, especially in battle grounds and situations where national security is under threat. in many situations when information in consideration is sensitive/confidential, it is in our best interests to analyze and share only needed information to minimize the potential of security breach regarding other irrelevant but sensitive information. Thus, the goal of this paper is to investigate the required methodologies and propose an advanced communication framework that enables different entities in distributed environments to identify, share and analyze only needed information, without disclosing other unwanted but sensitive information. Such a framework …

Wsrank: A Method For Web Service Ranking In Cloud Environment, Rong Hu, Wanchun Dou, Xiaoqing Frank Liu, Jianxun Liu

Computer Science Faculty Research & Creative Works

For services that have similar functionalities, if they are published by different cloud platforms, it is a challenge to evaluate them, for satisfying different end users' personal preferences. in view of this challenge, a method for web service ranking, named WSRank, is investigated in cloud environment in this paper. It aims at ranking different Web services published by different cloud platforms, taking advantage of Page Rank principle. at last, a case study and experiment are presented to demonstrate the feasibility of the method. © 2011 IEEE.

Information Flow Security In Cyber-Physical Systems, Thoshitha Gamage, Ravi Akella, Thomas Roth, Bruce Mcmillin

Computer Science Faculty Research & Creative Works

Preserving the confidentiality of sensitive internal actions is a unique challenge in Cyber-Physical Systems (CPSs) due to the inherent external observability of such systems and the tight coupling between their cyber and physical domains. the far-reaching objective of this work is to develop a science of self-obfuscating systems based on the composition of simple building blocks. a model of Nondeducibility composes the building blocks under information flow security properties. to this end, this paper proposes fundamental theories on external observability for basic regular networks and the concept of "event compensation". Copyright © 2011 ACM.

Link Activity Scheduling For Minimum End-To-End Latency In Multihop Wireless Sensor Networks, Maggie X. Cheng, Xuan Gong, Yibo Xu, Lin Cai

Computer Science Faculty Research & Creative Works

End-to-end delay is an important QoS metric in sensor networks as well as any application that involves transferring of small-sized files. in this paper, we address how to minimize the end-to-end delay in a multihop wireless network. End-to-end delay is defined as the total time it takes for a single packet to reach the destination. It is a result of many factors including the length of the routing path and the interference level along the path. in this paper we present a transmission scheduling scheme that minimizes the end-to-end delay along a given route. the link scheduling scheme is based …

A Cooperative Game Theoretic Approach For Data Replication In Mobile Ad-Hoc Networks, Dan Hirsch, Sanjay Madria

Computer Science Faculty Research & Creative Works

The mobile computing environment provides many benefits such as ubiquitous access to computing but include constraints on resources such as: Available bandwidth and battery life. Replication is a widely recognized method for balancing the demands of storage space with bandwidth and battery life. We propose a novel scheme that seeks to strategically balance these constrained resources through a cooperative game-theoretic approach for replication in a mobile environment. Our replication strategy relies on the cooperation of the nodes within the network to make replica caching decisions which are spatiotemporally local-optimal for the network from an energy and bandwidth conservation standpoint. in …

Scaling Laws Of Key Predistribution Protocols In Wireless Sensor Networks, Wenjun Gu, Sriram Chellappan, Xiaole Bai, Honggang Wang

Computer Science Faculty Research & Creative Works

Many key predistribution (KP) protocols have been proposed and are well accepted in randomly deployed wireless sensor networks (WSNs). Being distributed and localized, they are perceived to be scalable as node density and network dimension increase. While it is true in terms of communication/computation overhead, their scalability in terms of security performance is unclear. in this paper, we conduct a detailed study on this issue. in particular, we define a new metric called Resilient Connectivity (RC) to quantify security performance in WSNs. We then conduct a detailed analytical investigation on how KP protocols scale with respect to node density and …

Developing Hybrid Approaches To Predict Pka Values Of Ionizable Groups, Shawn Witham, Kemper Talley, Lin Wang, Zhe Zhang, Daquan Gao, Wei Yang, Emil Alexov

Publications

Accurate predictions of pKa values of titratable groups require taking into account all relevant processes associated with the ionization/deionization. Frequently, however, the ionization does not involve significant structural changes and the dominating effects are purely electrostatic in origin allowing accurate predictions to be made based on the electrostatic energy difference between ionized and neutral forms alone using a static structure. On another hand, if the change of the charge state is accompanied by a structural reorganization of the target protein, then the relevant conformational changes have to be taken into account in the pKa calculations. Here we report a hybrid …

Lithium In The Upper Centaurus Lupus And Lower Centaurus Crux Subgroups Of Scorpius-Centaurus, Eric J. Bubar, Marc Schaeuble, Jeremy R. King, Eric E. Mamajek, John R. Stauffer

Publications

We utilize spectroscopically derived model atmosphere parameters and the Li i λ6104 subordinate line and the λ6708 doublet to derive lithium abundances for 12 members of the Upper Centaurus Lupus and Lower Centaurus Crux subgroups of the Scorpius–Centaurus OB Association. The results indicate any intrinsic Li scatter in our 0.9–1.4 M stars is limited to ∼0.15 dex, consistent with the lack of dispersion in 1.0 M stars in the 100 Myr Pleiades and 30–50 Myr IC 2391 and 2602 clusters. Both ab initio uncertainty estimates and the derived abundances themselves indicate that the λ6104 line yields abundances with equivalent or …

Directional Limits On Persistent Gravitational Waves Using Ligo S5 Science Data, J. Abadie, Marco Cavaglia, For Full List Of Authors, See Publisher's Website.

Physics Faculty Research & Creative Works

The gravitational-wave (GW) sky may include nearby pointlike sources as well as stochastic backgrounds. We perform two directional searches for persistent GWs using data from the LIGO S5 science run: one optimized for pointlike sources and one for arbitrary extended sources. Finding no evidence to support the detection of GWs, we present 90% confidence level (C.L.) upper-limit maps of GW strain power with typical values between 2 - 20 x 10^-50 strain² Hz^-1 and 5 - 35 x 10^-49 strain²Hz^-1sr^-1 for pointlike and extended sources, respectively. The latter result is the …

Targeted Synthesis And Characterization Of Nanostructured Silicate Building Block Supports And Heterogeneous Catalysts With Tungsten(Vi) Or Zirconium(Iv) Centers, Michael Edward Peretich

Doctoral Dissertations

Catalysts play a vital role in almost every aspect of our lives and are used in the production of fuels, polymers, chemicals, foods, and pharmaceuticals. One challenge facing the heterogeneous catalysis community is the targeted synthesis of dispersed catalyst ensembles.

The Barnes research group has developed a general methodology for the synthesis of nanostructured silicate building block supports and heterogeneous catalysts. This methodology provides researchers with the ability to control the dispersion of surface functionality, the dispersion of metal cation centers, the number of linkages from the metal cation center to the support, the surface area of the support, and …

Population Of Low-Lying Levels In The One-Neutron Halo Nucleus 11be Via The Neutron Transfer Reaction 10be(D,P), Kyle Thomas Schmitt

Doctoral Dissertations

Historically, measurements of differential cross-sections for the neutron transfer reaction (d, p) on stable targets have been an important tool for extracting spectroscopic information. In particular, it is possible to make orbital angular momentum assignments and extract spectroscopic factors for ground states and excited states by comparing measurements to cross sections calculated for pure single-particle states. In recent years, the advent of rare isotope beams have made it possible to apply this method to increasingly exotic nuclei. As nucleon separation energies decrease along the path to the proton and neutron drip lines, many new reaction channels are opened. Out of …

Powersearch: Augmenting Mobile Phone Search Through Personalization, Xiangyu Liu

Computer Science and Computer Engineering Undergraduate Honors Theses

Cell phone has become a fundamental element of people's life. People use it to call each other, browse websites, send text messages, etc. Among all the functionalities, the most important and frequently used is the search functionality. Based on ComScore, in July 2008, Google was estimated to host 235 millions searches per day. However, unlike the search on desktop, the search on cell phone has one critical constrain: battery. Cell phone performing a normal Google search, the battery drains very fast. The reason is that when sending a query to and fetching the results from Google, cell phone keeps communicating …

Distributed Algorithms For Energy Savings In The Core Network, Lin Liu

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

Recently, many efforts have been undertaken to reduce the energy consumption of core networks. Bundle link is a commonly deployed technique in core networks to combine several high-speed physical sublinks into a virtual connection to achieve bandwidth upgrade flexibility and network reliability. The traffic passing through a bundle link can be carried fully over the first few sublinks (bin packing) or evenly distributed over all sublinks (load balancing). In the current network when a bundle link is on, all of its sublinks are on, thus, selectively shutting down a few sublinks during periods of low traffic could save a large …

Fabrication Of Mineralized Collagen From Bovine Waste Materials By Hydrothermal Method As Promised Biomaterials, Faheem A. Sheikh, M. A. Kanjwal, Javier Macossay-Torres, Muneeb A. Muhammad, Travis Cantu, Ioannis S. Chronakis, N. A. M. Barakat, Hak Yong Kim

Chemistry Faculty Publications and Presentations

In the present study, we aimed to produce mineralized-collagen by hydrothermal process. A simple method not depending on additional foreign chemicals has been employed to isolate the mineralized-collagen fibers from bovine waste. The process of extraction involves the use of hydrothermal method from available bovine bones. The structural and morphological properties of the collagen fibers were characterized by using scanning electron microscopy and transmission electron microscopy. These results indicated well received collagen fibers, having a diameter less than 1 μm and with established mineral content in the individual fibers. The X-ray diffraction showed the crystalline feature of the obtained nano-compounds. …