Physical Sciences and Mathematics Commons^™

Enhancing Asynchronous Parallel Computing, Elizabeth Anne Hamon

Dartmouth College Undergraduate Theses

In applications using large amounts of data, hiding the latency inherent in accessing data far from the processor is often necessary in order to achieve high performance. Several researchers have observed that one way to address the challenge of latency is by using a common structure: in a series of passes, the program reads in the data, performs various operations on it, and writes out the data. Passes often consist of a pipeline structure composed of different stages. In order to achieve high performance, the stages are frequently overlapped, for example, by using asynchronous threads. Out-of-core parallel programs provide one …

An Evaluation Of The Impact Of Models For Radio Propagation On The Simulation Of 802.11b Wireless Networks, Evan W. Richardson

Dartmouth College Undergraduate Theses

Working with an existing wireless network simulator, we describe the addition of both a method for modeling arbitrary terrain, and for calculating signal attenuation with the Irregular Terrain Model (ITM). We also investigate ITM's effects on upper protocol layer in comparison to the Two-Ray Ground Reflection model. Upon examination, it was found that aside from the terrain between the transmitter and receiver, ITM's various parameters are of little significance in the computed signal attenuation. Further, examination of the behavior of the upper protocol layers revealed that at high traffic levels, choice of propagation model can have significant effects on the …

802.11b Wireless Network Visualization And Radiowave Propagation Modeling, Chris Lentz

Dartmouth College Undergraduate Theses

This paper outlines the methods of creating detailed coverage maps of 802.11b networks, with an emphasis on minimizing the expenses and time involved. The goal of this work is to develop and present a streamlined, reproducible approach to wireless visualization as well as techniques for predicting coverage area before conducting network installations. After evaluating these coverage maps, a repeated series of field measurements will be checked against interpolated values in order to improve techniques for extrapolation of data for unsampled regions. If successful, these extrapolation techniques will provide additional guidelines for, and assist modeling of, new wireless network installations. However, …

Power Conservation In The Network Stack Of Wireless Sensors, Michael De Rosa

Dartmouth College Undergraduate Theses

Wireless sensor networks have recently become an incredibly active research area in the networking community. Much attention has been given to the construction of power-conserving protocols and techniques, as battery life is the one factor that prevents successful wide-scale deployment of such networks. These techniques concentrate on the optimization of network behavior, as the wireless transmission of data is the most expensive operation performed by a sensor node. Very little work has been published on the integration of such techniques, and their suitability to various application domains. This paper presents an exhaustive power consumption analysis of network stacks constructed with …

Southeast Nebraska Geology: Field Trip 3, Roger K. Pabian, Robert F. Diffendal, Jr. Jr., Darwin R. Boardman Ii

Robert F. Diffendal, Jr., Publications

The purpose of this trip is to familiarize you with the latest Pennsylvanian and earliest Permian rocks that are exposed in extreme southeastern Nebraska. You will see eight exposures of these rocks and will have ample opportunity to collect lithologic samples, as well as samples for both macro- and micro-fossils. The stops have been selected to show you examples of several different environments that existed in southeastern Nebraska in the late Paleozoic. These include subaerial deposits with paleosols, nearshore and offshore marine clastic and carbonate sequences. Each stop is covered in detail in the handouts that have been furnished to …

Ashfall Historic Park: Field Trip 5, Robert F. Diffendal Jr.

Robert F. Diffendal, Jr., Publications

Ashfall Fossill Beds: A State Historical Park. Brochure. Nebraska Game and Parks Commission and University of Nebraska State Museum

Research Reports, 1978. Projects: A Miocene Rhinoceros Herd Buried in Volcanic Ash. Grant Recipient: Michael R. Voorhies, Division of Vertebrate Paleontology, University of Nebraska State Museum, Lincoln, Nebraska.

Geologic Framework of the Niobrara River Drainage Basin and Adjacent Areas in South Dakota Generally East of the 100th Meridian West Longitude and West of the Missouri River Robert F. Diffendal, Jr. and Michael R. Voorhies. Nebraska Geological Survey Report of Investigations, number 9.

Use Of Optical Tweezers For Colloid Science, Andrew Resnick

Physics Faculty Publications

A space-borne optical tweezer apparatus for use with colloidal crystallization experiments has been characterized. The trapping force has been measured as a function of index mismatch between colloidal microspheres and the surrounding fluid and as a function of particle size. This work also presents a method to determine the refractive index of a colloidal microsphere, which is then used to calculate the applied trapping force for the case of an arbitrary background fluid. This is useful for work with dense colloidal suspensions when the usual (e.g., Stokes flow) trap force measurement methods do not apply, as well as microrheological studies …

Perilipin A Is Essential For The Translocation Of Hormone-Sensitive Lipase During Lipolytic Activation. J Cell Biol, John Tansey

Chemistry Faculty Scholarship

A key step in lipolytic activation of adipocytes is the translocation of hormone-sensitive lipase (HSL) from the cytosol to the surface of the lipid storage droplet. Adipocytes from perilipin -null animals have an elevated basal rate of lipolysis compared with adipocytes from wild-type mice, but fail to respond maximally to lipolytic stimuli. This defect is downstream of the -adrenergic receptor–adenylyl cyclase complex. Now, we show that HSL is basally associated with lipid droplet surfaces at a low level in perilipin nulls, but that stimulated translocation from the cytosol to lipid droplets is absent in adipocytes derived from embryonic fibroblasts of …

Links Between Snow Cover, Surface Skin Temperature, And Rainfall Variability In The North American Monsoon System, Toshi Matsui, Venkataraman Lakshmi, Eric Small

Faculty Publications

The influence of land–atmosphere interactions on the variability of the North American monsoon system(NAMS) is investigated using the Television Infrared Observation Satellite (TIROS) Operational Vertical Sounder(TOVS) Pathfinder, the Climate Prediction Center (CPC) gauge precipitation, and observed snow water equivalent(SWE). Three hypotheses are tested regarding the connection between land surface variables and precipitationin the NAMS region. First, there is a weak negative correlation between 1 April SWE and subsequent surfacetemperature in the southern Rocky Mountains (SRM) region. However, this connection persists only until Juneand, therefore, cannot directly influence monsoon rainfall in July and August. Second, there is a negativecorrelation between SRM …

Afci Quarterly Input – Unlv April Through June, 2003, Harry Reid Center For Environmental Studies. Nuclear Science And Technology Division

Transmutation Research Program Reports (TRP)

The University of Nevada, Las Vegas supports the AFCI through research and development of technologies for economic and environmentally sound refinement of spent nuclear fuel. The UNLV program has four components: infrastructure, international collaboration, student-based research, and management and program support.

Quarterly Report For The Trp Project, March–June 2003, Samir Moujaes, Yitung Chen, Kanthi Kiran Daiska, Chao Wu

Transmutation Sciences Materials (TRP)

The MTL is assumed to be a 5m long rectangular loop with a circular cross-section. Because of the non-symmetry, and due to the active participation of the secondary flows due to the elbows present in the rectangular loop model, the geometry is considered as a 3D model.

When the regions of maximum corrosion and precipitation are compared, they fall in the same zone for both the analytical and simulated models. The reason for a larger concentration flux in the case of turbulent flow than for the laminar flow can be explained by the concept of higher lateral diffusion in the …

Immobilization Of Fission Iodine By Reaction With A Fullerene Containing Carbon Compound And Insoluble Natural Organic Matrix: Quarterly Report April-June 2003, Spencer M. Steinberg

Separations Campaign (TRP)

The recovery of iodine released during the processing of used nuclear fuel poses a significant challenge to the transmutation of radioactive iodine. This proposal will develop and examine the use of Fullerene Containing Carbon (FCC) compounds as potential sorbents for iodine release from the reprocessing of nuclear fuel. This work will also include the development of bench-scale testing capabilities at UNLV to allow the testing of the FCC material in a simulated process off-gas environment. This experimental capability will also be used to test other potential sorption materials and processes, such as natural organic matter (NOM) and other promising alternatives. …

Inside Unlv, Kevin Force, Gian Galassi, Carol C. Harter, Stuart Mann

Inside UNLV

No abstract provided.

A Monte Carlo Analysis Of Hedonic Models Using Traditional And Spatial Approaches, Helen R. Neill, David M. Hassenzahl, Djeto D. Assane

Public Policy and Leadership Faculty Publications

Hedonic regression analysis of single family homes typically includes structural variables, locational variables and neighborhood quality characteristics. When nearby properties are related, Dubin (1988) reports that error terms are spatially autocorrelated. Estimation methods for these spatially autocorrelated error terms or hereafter, spatial approaches, include maximum likelihood estimation (MLE) and kriging techniques such as kriged maximum likelihood estimation (KMLE). Unfortunately these spatial methods require massive computer resources and are limited to significantly fewer observations than traditional ordinary least squares (OLS). This paper investigates the combination of spatial approaches and Monte Carlo analysis, a method that approximates large data sets. A question …

Dynamic Joint Action Perception For Q-Learning Agents, Nancy Fulda, Dan A. Ventura

Faculty Publications

Q-learning is a reinforcement learning algorithm that learns expected utilities for state-action transitions through successive interactions with the environment. The algorithm's simplicity as well as its convergence properties have made it a popular algorithm for study. However, its non-parametric representation of utilities limits its effectiveness in environments with large amounts of perceptual input. For example, in multiagent systems, each agent may need to consider the action selections of its counterparts in order to learn effective behaviors. This creates a joint action space which grows exponentially with the number of agents in the system. In such situations, the Q-learning algorithm quickly …

Microspectrophotometry Of Respiratory Pigments, Karen Yvonne Kavanagh

Doctoral

This research thesis describes the design, construction and optical testing of three fibre-optic microspectrophotometer systems to monitor the reduction of mitochondrial respiratory pigments. The optical and biochemical characteristics of mitochondrial respiration are discussed and the current optical techniques employed in the biochemical analysis of respiratory enzymes are presented. The primary focus of this study is the system parameters surrounding the spectrophotometric determination of mitochondrial respiratory activity. Three separate fibre-optic set-ups are described, which use visible spectrophotometry to measure the reduction of mitochondrial electron carriers from a range of biological sources. Each system is based around the Ocean Optics S1000/S2000 series …

Utilizing Of Elemental Sulfur From Oil And Gas Industry For Soil Treatment, Sultan Saif R. A. Alshamsi

Theses

The United Arab Emirates produces a large quantity of elemental sulfur from oil and gas industry. Elemental sulfur is widely used as soil treatment technique for reducing pH of alkaline soils than other techniques because it is cheaper and safer during treatment.

In this study, different designs mixes were prepared based on its content of sulfur and calcium carbonate. Different application rates of elemental sulfur (0, 1, 2, and 3%S) were added to soils having different amounts of calcium carbonates (i.e., 16.2, 21.2, 26.2, 36.2, 46.2, and 56.2% for basic mix design, and mix designs types I, II, III, IV, …

Optimal Sizing Of Activated Sludge Domestic Wastewater Treatment Processes Considering Uncertainties, Abdulhameed A. Arwani

Theses

A mathematical framework is developed for use in the optimal sizing of a wastewater treatment system comprises an activated sludge system preceded by a primary clarifier. Mathematical models predicting the performance of various unit processes are used to construct the system model. ASM3, used in the developed framework, is among the most recent and comprehensive models that closely describe the biological reactions taking place in the activated sludge system. Cost information functions including capital and operational costs of different system units are also modeled. An optimization problem is formulated with the objective to produce optimal sizes of different units with …

Assessment Of Groundwater Resources Using Remote Sensing And Gis, Muna Khalil Al Hammadi

Theses

Geographical Information Systems and Remote Sensing have witnessed an enormous interest in various applications related to geology, hydrology, hydrogeology, and water resources. The use of GIS and remote sensing has become a common practice worldwide. The UAE is no exception. The study of groundwater resources and its sustainability is of prime concern for authorities in the UAE. Although, groundwater may not be suitable, in most cases, for drinking and other potable purposes, it represents the main source for irrigation in the country. About 85% of the total water consumption in the UAE is groundwater.

This study is devoted to the …

Effects Of Lining Cooling Tower Interior Walls On Controlling The Growth Of Legionella Pneumophila, Kamal Rafiq Saeed Jaroor

Theses

The presence of Legionella pneumophila in cooling tower waters is a serious health hazard. If the contaminated mist from the cooling tower is inhaled, Legionnaires' disease could be contracted. Of the 2.4 million cases of pneumonia that occur each year in the United States, an estimated 8,000 to 18,000 are actually cases of Legionnaires' disease. Several factors have been suggested in the literature that enhance the high bacterial count in cooling towers including: temperature, pH, water stagnation, and presence of algae and protozoa.

On few occasions, water samples from the cooling tower at Dubai Hospital tested positive for Legionella pneumophila …

Treatment Of Petroleum Refinery Wastewater Effluent Using Coupled Carbon Sorption And Biodegradation, Fatin Ali Sadiq Sawalha

Theses

There has been increased interest in the development of technologies for the effective removal of priority pollutants from petroleum refineries and thereby protect the quality of receiving water. In this study, the removal of phenol and naphthalene from aqueous solutions using different bacterial strains, granular activated carbon and biological activated carbon as a combination of the two systems were investigated. Laboratory-scale experiments for the adsorption, biodegradation and biosorption of the two chemicals were conducted in batch reactors at 25°C and shaking at 120 rpm. Pure bacterial cultures of phenol-utilizing bacteria and naphthalene-utilizing bacteria were isolated from local enriched soil and …

Treatment Of Industrial Wastewater From Food Processing Plant Under Climate Conditions, Saeed Mohamed Wali Abdulla Karmustaji

Theses

This research thesis will study the performance of wastewater treatment plant using a two-phase continuous flow anaerobic/aerobic treatment plant for the treatment of industrial wastewater from a confectionary factory in Dubai. The treatment design is based on anaerobic process under mesophilic conditions (31 +/- 2 °C) range where only the heat of the inlet and the natural climatic temperature are utilized to maintain the reactor operational. An aerobic activated sludge process to achieve the required legal standards follows the anaerobic treatment.

During the anaerobic process, biogas is generated and stored in a collection chamber and linked to an automated flared …

Hydrogeological And Geophysical Studies On Ai Jaww Plain, Ai Ain Area, U.A.E., Hind Saif Ali Ai-Nuaimi

Theses

No abstract provided.

The John Muir Newsletter, Summer 2003, The John Muir Center For Environmental Studies

Muir Center Newsletters (1981-2015)

JOHIMUI Newsletter UNlVfeRSnYOFTffi Volume 13, Number 3 Summer 2003; The Tramps by Edmund Herlihy, Mission Viejo, CA (Editor :s note: Edmund Herlihy is an Environmental Studies major at the University of the Pacific. This paper was prepared in the fall of 2002 for an undergraduate course, "John Muir and the Environment") 7magine a vast expanse of raw untamed land where a man might make a fortune as quickly as he might be scalped — the American West during the late 1800's was the frontier where one could pack up and start a whole new life west of the great Mississippi. …

New Graphical Approach On The Analysis Of Experimental Data, Suha Sari

Dissertations

This study presents a new graphical method to identify significant effects in factorial experiments. The proposed methods are obtained for the different cases in which the design can be of full factorial or fractional factorial and the factor levels can be pure or mixed.

We focus on the different decomposition methods, for example orthogonal components system and orthogonal contrast method, to make use of the chisquare plot which requires that the sums of squares are of the same degrees of freedom. Examples and simulations illustrating the different cases of the procedure are presented.

Automatic Processing Of High-Rate, High-Density Multibeam Echosounder Data, Brian R. Calder, Larry A. Mayer

Center for Coastal and Ocean Mapping

Multibeam echosounders (MBES) are currently the best way to determine the bathymetry of large regions of the seabed with high accuracy. They are becoming the standard instrument for hydrographic surveying and are also used in geological studies, mineral exploration and scientific investigation of the earth's crustal deformations and life cycle. The significantly increased data density provided by an MBES has significant advantages in accurately delineating the morphology of the seabed, but comes with the attendant disadvantage of having to handle and process a much greater volume of data. Current data processing approaches typically involve (computer aided) human inspection of all …

Earthscoping The Inner Workings Of Magmatic Systems, Michael Hamburger, Stephen R. Mcnutt, Daniel Dzurisin, Jonathan Fink, David P. Hill, Charles Meertens, Chris Newhall, Susan Owen, John A. Power

School of Geosciences Faculty and Staff Publications

In the shadow of one of the world's great volcanic systems, an intensive 3‐day workshop was undertaken to work toward developing a scientific plan for the magmatic systems component of the U.S. National Science Foundation's (NSF) EarthScope Initiative. This NSF‐sponsored workshop was designed to provide direction to the EarthScope planning committee and the NSF in developing scientific, technical, deployment, and management decisions related to the magmatic systems component of EarthScope. The meeting featured a mixture of oral and poster scientific sessions, breakout group and plenary discussions, and a field trip to examine one of the targets of the EarthScope magmatic …

Localized Ferromagnetic Resonance In Inhomogeneous Thin Films, R. D. Mcmichael, D. J. Twisselmann, Andrew Kunz

Physics Faculty Research and Publications

The effect of sample inhomogeneity on the ferromagnetic resonance linewidth is determined by diagonalization of a spin wave Hamiltonian for ferromagnetic thin films with inhomogeneities spanning a wide range of characteristic length scales. A model inhomogeneity is used that consist of size D grains and an anisotropy field H_p that varies randomly from grain to grain in a film with thickness d and magnetization M_s. The resulting linewidth agrees well with the two-magnon model for small inhomogeneity, H_pD « πM_sd. For large inhomogeneity, H_pD » πM_sd the precession …

Bioassessment Of The West Fork Of The White River, Northwest Arkansas, Arthur V. Brown, Andrea J. Radwell, Robin A. Reese

Technical Reports

The West Fork-White River has been and continues to be an important water resource for northwest Arkansas. It is used recreationally for fishing and swimming, agriculturally as a source of water for livestock and irrigation of crops, it is mined for gravel, used as a receiving stream for municipal wastewater effluent, and contributes to Beaver Lake which provides water for treatment and distribution to most of northwest Arkansas. While these uses have benefited a large segment of the Arkansas population, they have also contributed to the decline in environmental quality of the river. To facilitate the development of appropriate management …

The Role Of The Dielectric Barrier In Narrow Biological Channels: A Novel Composite Approach To Modeling Single-Channel Currents, Artem B. Mamonov, Rob D. Coalson, Abraham Nitzan, Maria G. Kurnikova

Chemistry Faculty Research and Publications

A composite continuum theory for calculating ion current through a protein channel of known structure is proposed, which incorporates information about the channel dynamics. The approach is utilized to predict current through the Gramicidin A ion channel, a narrow pore in which the applicability of conventional continuum theories is questionable. The proposed approach utilizes a modified version of Poisson-Nernst-Planck (PNP) theory, termed Potential-of-Mean-Force-Poisson-Nernst-Planck theory (PMFPNP), to compute ion currents. As in standard PNP, ion permeation is modeled as a continuum drift-diffusion process in a self-consistent electrostatic potential. In PMFPNP, however, information about the dynamic relaxation of the protein and the …