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Articles 451 - 480 of 1435
Full-Text Articles in Physical Sciences and Mathematics
On The Complexity Of Collecting Items With A Maximal Sliding Agent, Pedro J. Tejada
On The Complexity Of Collecting Items With A Maximal Sliding Agent, Pedro J. Tejada
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
We study the computational complexity of collecting items inside a grid map with obstacles, using an agent that always slides to the maximal extend, until it is stopped by an obstacle. An agent could be, for example, a robot or a vehicle, while obstacles could be walls or other immovable objects, and items could be packages that need to be picked up.
This problem has very natural applications in robotics. The restricted type of motion of the agent naturally models movement on a frictionless surface, and movement of a robot with limited sensing capabilities and thus limited localization. For example, …
Improving Reuse And Maintainability Of Communication Software With Conversation-Aware Aspects, Ali Raza
Improving Reuse And Maintainability Of Communication Software With Conversation-Aware Aspects, Ali Raza
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Inter-process communications (IPC) are ubiquitous in today’s software systems, yet they are rarely treated as first-class programming concepts. Implementing crosscutting concerns for message-based IPC are difficult, even using aspect-oriented programming languages (AOPL) such as AspectJ. Many of these challenges are because the context of a communication-related crosscutting concern is often a conversation consisting of message sends and receives. Hence, developers typically have to implement communication protocols manually using primitive operations, such as connect, send, receive, and close. This dissertation describes an extension to AspectJ, called CommJ, with which developers can implement communication-related concerns in cohesive and loosely coupled aspects. It …
Pathway Pioneer: A Web-Based Metabolic Network Layout Extension, Harsh Dosi
Pathway Pioneer: A Web-Based Metabolic Network Layout Extension, Harsh Dosi
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The number and complexity of genome-scale metabolic networks have seen a rapid growth in the past 10 years. Today, more than 450 genome-scale metabolic reconstructions of biological systems are characterized and existing models are extended. With the growing influence of these reconstructions on biomedical and biological research, the field has observed a shift from an inward focus on method development to an outward focus on application development.
Static state analysis of metabolic networks in textual format is too cumbersome and time consuming. In addition, visualization and arrangement of these networks to facilitate their analysis is an open research problem. A …
Pathway Pioneer: A Web-Based Graphical Tool For The Organization And Flux Analysis Of Metabolic Networks, Sumit Kumar Singh
Pathway Pioneer: A Web-Based Graphical Tool For The Organization And Flux Analysis Of Metabolic Networks, Sumit Kumar Singh
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Every so often the field of genome-scale metabolic networks undergoes radical changes, each bringing its own complexity and challenges. The existing visualization tools, owing to their inability to assist in generating layouts suitable for easy readability and conceptualization, hinder further advancement. The lack of in-depth comprehensible representation of the intricacies of interaction and arrangements within the network topology prevents researchers from being able to advance at a faster speed despite the growing number of networks and systems. The far and wide diverse standards, layout schemas and network formats of the biological realm contribute to the existing challenges of developing visualization …
Exploring Visitor Attitudes Toward The Proposed Greater Canyonlands National Monument: A Survey In Utah's Indian Creek Corridor, Chase C. Lamborn
Exploring Visitor Attitudes Toward The Proposed Greater Canyonlands National Monument: A Survey In Utah's Indian Creek Corridor, Chase C. Lamborn
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
In August of 2012, the Outdoor Industry Association (OIA) sent a letter to President Barack Obama asking him to designate the Greater Canyonlands National Monument (GCNM). The proposed 1.4 million acre national monument would surround the already present 337,570 acre Canyonlands National Park, and would include public lands/waterways from five Utah counties. The OIA’s goal for the GCNM is to preserve the landscape for quality outdoor recreation by decreasing the amount of off-highway vehicle use and to eliminate the possibility of oil/gas drilling and mining. Given the proposal highlights outdoor recreation use benefits as the main catalyst for justification of …
Understanding Local Perceptions And The Role Of Historical Context In Ecotourism Development: A Case Study Of St. Kitts, Amber Greening
Understanding Local Perceptions And The Role Of Historical Context In Ecotourism Development: A Case Study Of St. Kitts, Amber Greening
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Ecotourism is a popular tool for the conservation of fragile ecosystems and local development of the communities surrounding them. It is widely argued that the key to effective and sustainable ecotourism programs relies on the depth of community involvement and support. This research reveals a better understanding of community members’ perceptions of ecotourism and conservation, and how these perceptions potentially influence participation in current and future ecotourism projects within the villages of Cayon and Keys on the Caribbean island of St. Kitts. Data were collected through several qualitative methods including: face-to-face surveys with Cayon and Keys villagers; interviews with government …
The Human Dimensions Of Climate Change: Smallholder Perception And Adaptation In The Loess Plateau Region Of China, Morey Burnham
The Human Dimensions Of Climate Change: Smallholder Perception And Adaptation In The Loess Plateau Region Of China, Morey Burnham
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Climate change poses problems for agriculture in the Global South. Smallholders in the Global South are often considered highly vulnerable to climate change as a result of their farms being located in marginal environments, their insecure land tenure and lack of technology, and their participation in unpredictable regional and world markets. Analyzing how smallholders perceive climate change and attendant risk, the factors that enable and constrain their adaptive capacity, and the social impacts of state led projects designed to mitigate the impacts of climate change may provide crucial insights for developing effective climate adaption projects and policies. This research examined …
Automated Reverse Engineering Of Malware To Develop Network Signatures To Match With Known Network Signatures, Dan Sinema
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Illicit software that seeks to steal user information, deny service, or cause general mayhem on computer networks is often discovered after the damage has been done. The ability to discover network behavior of software before a computer network is utilized would allow administrators to protect and preserve valuable resources. Static reverse engineering is the process of discovering in a offline environment how a software application is built and how it will behave. By automating static reverse engineering, software behavior can be discovered before it is executed on client devices. Fingerprints are then built from the discovered behavior which is matched …
Linking Montane Soil Moisture Measurements To Evapotranspiration Using Inverse Numerical Modeling, Ling Lv
Linking Montane Soil Moisture Measurements To Evapotranspiration Using Inverse Numerical Modeling, Ling Lv
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Evapotranspiration (ET) and soil moisture play important roles in annual water delivered from snowpack to reservoirs, lakes and streams. Indeed, ET and soil moisture are key factors dictating the performance of the regional climate models in the intermountain west (IMW) of the USA. Water resources management and climate modeling require accurate prediction of ET and areal soil moisture for reliable estimates of ongoing and future water needs. This research has examined ways to estimate ET from four common vegetation types in the IMW (aspen, conifer, grass and sage) using local soil moisture measurements from an advanced instrumentation network located in …
Conformal Gravity And Time, Jeffrey Shafiq Hazboun
Conformal Gravity And Time, Jeffrey Shafiq Hazboun
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Within the last year, two acclaimed physics experiments have probed further into the extremes of our physical understanding. The Large Hadron Collider, the largest experiment ever constructed, has detected a Higgs boson, which establishes a mass scale for the fundamental particles. The Planck mission satellite has made the most accurate measurements of the cosmic microwave background radiation, which is the oldest data about the early universe we are currently able to measure directly. The mission corroborated the proportions of dark matter and dark energy are all very close to expected values. While these experiments have helped solidify the current working …
Statistical Modeling, Exploration, And Visualization Of Snow Water Equivalent Data, James Beguah Odei
Statistical Modeling, Exploration, And Visualization Of Snow Water Equivalent Data, James Beguah Odei
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Due to a continual increase in the demand for water as well as an ongoing regional drought, there is an imminent need to monitor and forecast water resources in the Western United States. In particular, water resources in the Intermountain West rely heavily on snow water storage. Thus, the need to improve seasonal forecasts of snowpack and considering new techniques would allow water resources to be more effectively managed throughout the entire water-year. Many available models used in forecasting snow water equivalent (SWE) measurements require delicate calibrations.
In contrast to the physical SWE models most commonly used for forecasting, we …
Network Applications And The Utah Homeless Network, Michael A. Snyder
Network Applications And The Utah Homeless Network, Michael A. Snyder
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Graph theory is the foundation on which social network analysis (SNA) is built. With the flood of "big data," graph theoretical concepts and their linear algebraic counterparts are essential tools for analysis in the burgeoning field of network data analysis, in which SNA is a subset. Here we begin with an overview of SNA. We then discuss the common descriptive measures taken on network data as well as proposing new measures specific to homeless networks. We also define a new data structure which we call the location sequence matrix. This data structure makes certain computational network analyses particularly easy. …
Landscape Evolution Of The Needles Fault Zone, Utah, Investigated Through Chronostratigraphic And Terrain Analyses, Faye L. Geiger
Landscape Evolution Of The Needles Fault Zone, Utah, Investigated Through Chronostratigraphic And Terrain Analyses, Faye L. Geiger
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Arcing eastward from the deep gorge of Cataract Canyon on the Colorado River is a series of aligned valleys (graben) and ridges (horst). This unusual landscape has formed as subsurface salt deforms toward the river and dissolves away, causing the overlying rocks to fault, slide, and subside. Geologists have long been interested in this actively evolving area they call the Needles fault zone, because understanding its mechanics and origin may shed light on how faults work in general and similar, yet inaccessible places like offshore rift zones or even the surface of the Moon. Despite this interest, the timing and …
Bay Of Bengal: Coupling Of Pre-Monsoon Tropical Cyclones With The Monsoon Onset In Myanmar, Boniface Opoku Fosu
Bay Of Bengal: Coupling Of Pre-Monsoon Tropical Cyclones With The Monsoon Onset In Myanmar, Boniface Opoku Fosu
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Myanmar remained largely closed to the world through political instability for several years, when it continued to suffer terribly at the hands of nature that remained largely unknown. Of note is the period between 2008 and 2013, during which the country suffered at least eight major natural calamities that killed more than 141,000 people and affected 3.2 million. The worst of these was Cyclone Nargis in May 2008 that killed more than 130,000. With an estimated $4 billion in damages, Nargis remains the deadliest and most destructive named cyclone ever to have occurred in the North Indian Ocean. Recent studies …
Online Media Use And Adoption By Hurricane Sandy Affected Fire And Police Departments, Apoorva Chauhan
Online Media Use And Adoption By Hurricane Sandy Affected Fire And Police Departments, Apoorva Chauhan
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
In this thesis work, I examine the use and adoption of online communication media by 840 fire and police departments that were affected by the 2012 Hurricane Sandy. I began by exploring how and why these fire and police departments used (or did not use) online media to communicate with the public during Hurricane Sandy. Results show that fire and police departments used online media during Hurricane Sandy to give timely and relevant information to the public about things such as evacuations, damages, weather, and cleanup and to engage in two-way communications with their constituents. In their messages, fire and …
Information And Hardness Quantification Of Graphs: A Computational Study, Brent Dutson
Information And Hardness Quantification Of Graphs: A Computational Study, Brent Dutson
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
New techniques to measure the information contained within a network of interconnected nodes (such as links between computers in the Internet) have recently been developed. This work studies the relationship between the computer time needed to solve a common network problem and the information contained within the given network.
Modeling The Defect Density Of States Of Disordered Sio2 Through Cathodoluminescence, Amberly Evans Jensen
Modeling The Defect Density Of States Of Disordered Sio2 Through Cathodoluminescence, Amberly Evans Jensen
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Spacecraft charging is the accumulation of an electrical charge on orbiting spacecraft induced by the space plasma environment and has harmful effects on the electrical functionality of a spacecraft. This is studied extensively, particularly in the Materials Physics Group (MPG) at Utah State University (USU). During charging studies performed by the MPG, another potentially problematic effect of the space plasma environment on spacecraft was observed: light emanating from the sample undergoing electron beam bombardment. Space-based observatories are one type of spacecraft on which this luminescence may occur. If the luminescence from the material caused by the space plasma is within …
The Kimama Core: A 6.4 Ma Record Of Volcanism, Sedimentation, And Magma Petrogenesis On The Axial Volcanic High, Snake River Plain, Id, Katherine Elizabeth Potter
The Kimama Core: A 6.4 Ma Record Of Volcanism, Sedimentation, And Magma Petrogenesis On The Axial Volcanic High, Snake River Plain, Id, Katherine Elizabeth Potter
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The Snake River Plain (SRP) is one of the best-preserved examples of continental hotspot volcanis, with a continuous record of volcanism that extends over 16 Ma to the present. Yellowstone-Snake River Plain records the migration of plume-tail volcanism from inception at the Bruneau-Jarbridge caldera complex at 12.6 Ma to its present locus, under the Yellowstone Plateau.
Records kept by the Snake River Plain volcanic actions include rhyolite lavas and ignimbritesm minor coeval basalts, and an overlying veneer of younger basalts. The central SRP has received comparatively little attention in the past. The Kimama core hole was drilled as part of …
Minimizing Aggregate Movements For Interval Coverage, Aaron M. Andrews
Minimizing Aggregate Movements For Interval Coverage, Aaron M. Andrews
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
We present an efficient algorithm for solving an interval coverage problem. Given n intervals of the same length on a line L and a line segment B on L, we want to move the intervals along L such that every point of B is covered by at least one interval and the sum of the moving distances of all intervals is minimized. As a fundamental computational geometry problem, it has applications in mobile sensor barrier coverage in wireless sensor networks. The previous work gave an O(n2) time algorithm for it. In this thesis, by discovering …
In Situ Stress And Geology From The Mh-2 Borehole, Mountain Home, Idaho: Implications For Geothermal Exploration From Fractures, Rock Properties, And Geomechanics, James Andrew Kessler
In Situ Stress And Geology From The Mh-2 Borehole, Mountain Home, Idaho: Implications For Geothermal Exploration From Fractures, Rock Properties, And Geomechanics, James Andrew Kessler
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Geothermal energy is being explored as a supplement to traditional fossil fuel resources to meet growing energy demand and reduce carbon emissions. Geothermal energy plants harvest heat stored in the Earth’s subsurface by bringing high temperature fluids to the surface and generating steam to produce electricity. Development of geothermal resources is often inhibited by large upfront risk and expense. Successful mitigation of those costs and risks begins with efficient characterization of the resource before development. A typically successful geothermal reservoir consists of a fractured reservoir that conducts hydrothermal fluids and a cap rock seal to limit convective heat loss through …
Multiplicity Results Of Periodic Solutions For Two Classes Of Nonlinear Problems, Kazuya Hata
Multiplicity Results Of Periodic Solutions For Two Classes Of Nonlinear Problems, Kazuya Hata
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
We investigate the existences and qualitative properties of periodic solutions of the following two classes of nonlinear differential equations:
I) (Special) Relativistic Pendulum Equations (RPEs);
II) (2-coupled) Gross-Pitaevskii Equations (GPEs).
The pendulum equation describes the motion of a pendulum. According to Special Relativity, which was published by A. Einstein in 1905, causality is more fundamental than constant time-space, thus time will flow slower and space will distort to keep causality if the speed of motion is near the speed of light. In such high speed situations, the pendulum equation needs to be revised due to Special Relativity. The revised equation …
Hamiltonicity, Pancyclicity, And Cycle Extendability In Graphs, Deborah C. Arangno
Hamiltonicity, Pancyclicity, And Cycle Extendability In Graphs, Deborah C. Arangno
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
A significant portion of Graph Theory is devoted to determining the characteristics which guarantee the existence of long cycles.
Long cycles have roles in applications to civil engineering, chemistry, and communications, among many others, but the problem, in and of itself, of determining whether a graph has a cycle of some fixed and typically large length is one of the most important problems of both pure Mathematics and Computer Science.
A cycle containing all the vertices of the graph is called a Hamiltonian cycle, and a graph which possesses such a cycle is said to be Hamiltonian. If …
Multiversejava, Vishal Sharma
Multiversejava, Vishal Sharma
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Sequenced semantics, which was first proposed in the context of temporal databases, is the semantics for the evaluation of a program on values annotated with time metadata. The time metadata records when each value is “live” (is valid or has existence). Sequenced semantics stipulates that a computation on values annotated with temporal metadata must be equivalent to, in effect, running the computation at every time point with only the values alive at that time. Sequenced semantics is challenging to program because it is more than just a re-interpretation of the run-time behavior of a program; for instance, a sequenced “if-else” …
Soil Water Flux Estimates From Streaming Potential And Penta-Needle Heat Pulse Probe Measurements, Pawel J. Szafruga
Soil Water Flux Estimates From Streaming Potential And Penta-Needle Heat Pulse Probe Measurements, Pawel J. Szafruga
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Growing populations, coupled with climate change and resource depletion, have heightened concern about water management. The growing need to better manage agricultural systems, including irrigation and fertilizer application, as well the lasting consequences of excess application of nitrogen and other nutrients, could be remedied with an improved method to monitor soil water movement. Despite huge technological advances, a tool to measure soil water flow at the low rates found in the field has not been developed. Current methods lack the precision to provide the needed accuracy to fully understand soil-water dynamics, as well as the ability to provide instantaneous information. …
Structure And Multi-Center Bonding: From Atomic Clusters To Solid Phase Materials, Timur R. Galeev
Structure And Multi-Center Bonding: From Atomic Clusters To Solid Phase Materials, Timur R. Galeev
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The work presented in this dissertation has been focused on structure, stability, and chemical bonding of atomic clusters and solid-state compounds. The common thread was development of theoretical models and methods capable of interpreting bonding and hence, structures of these species. A major part of this work presents joint experimental and theoretical studies of a large series of doped boron clusters. The dissertation introduces a new theoretical tool for interpretation of bonding of solid phase materials in chemically intuitive terms of localized and multi-center bonds. Understanding how interactions between atoms in sub-nano clusters and solid-state compounds determine their structures, physical …
Computational Models Of Intracellular And Intercellular Processes In Developmental Biology, Ahmadreza Ghaffarizadeh
Computational Models Of Intracellular And Intercellular Processes In Developmental Biology, Ahmadreza Ghaffarizadeh
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Systems biology takes a holistic approach to biological questions as it applies mathematical modeling to link and understand the interaction of components in complex biological systems. Multiscale modeling is the only method that can fully accomplish this aim. Mutliscale models consider processes at different levels that are coupled within the modeling framework. A first requirement in creating such models is a clear understanding of processes that operate at each level. This research focuses on modeling aspects of biological development as a complex process that occurs at many scales. Two of these scales were considered in this work: cellular differentiation, the …
Beetles, Fungi And Trees: A Story For The Ages? Modeling And Projecting The Multipartite Symbiosis Between The Mountain Pine Beetle, Dendroctonus Ponderosae, And Its Fungal Symbionts, Grosmannia Clavigera And Ophiostoma Montium, Audrey L. Addison
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
As data collection and modeling improve, ecologists increasingly discover that interspecies dynamics greatly affect the success of individual species. Models accounting for the dynamics of multiple species are becoming more important. In this work, we explore the relationship between mountain pine beetle (MPB, Dendroctonus ponderosae Hopkins) and two mutualistic fungi, Grosmannia clavigera and Ophiostoma montium. These species are involved in a multipartite symbiosis, critical to the survival of MPB, in which each species benefits.
Extensive phenological modeling has been done to determine how temperature affects the timing of life events and cold-weather mortality of MPB. The fungi have also …
Decision Making Using Trust And Risk In Self-Adaptive Agent Organization, Kamilia Ahmadi
Decision Making Using Trust And Risk In Self-Adaptive Agent Organization, Kamilia Ahmadi
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Interaction between agents is one of the key factors in multi-agent societies in order to cooperatively execute complex tasks which are beyond the capability of a single agent. In the self-adaptation society, agents try to keep best neighbors around themselves. Agents use history of past iterations to evaluate their neighbors and locally modify their structural links. Main characteristics of this model are its decentralization, dynamicity and no need of external control. This research at first deals with implementing self-adaptive agent organization. Then it focuses on evaluating cooperation peers in decision making. Trust as an evaluation mechanism lies at the core …
Computational Topics In Lie Theory And Representation Theory, Thomas J. Apedaile
Computational Topics In Lie Theory And Representation Theory, Thomas J. Apedaile
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The computer algebra system Maple contains a basic set of commands for working with Lie algebras and matrices. The purpose of this thesis was to extend the functionality of these Maple packages in a number of important areas. First, programs for defining multiplication in several different types of algebras were created to allow users to perform a wider variety of calculations. Second, commands were created for calculating some basic properties of matrix representations of semisimple Lie algebras. This allows a user to identify a given matrix representation by a collection of integers which do not change when the basis of …
Physically Based Preconditioning Techniques Applied To The First Order Particle Transport And To Fluid Transport In Porous Media, Michael Rigley
Physically Based Preconditioning Techniques Applied To The First Order Particle Transport And To Fluid Transport In Porous Media, Michael Rigley
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Solving linear systems is at the heart of many scientific applications from the PreAlgebra's student solving for x and y for basic geometry problems to the computational scientist solving billions of equations with billions of variables for weather forecasting, modeling fusion reactions, or web search algorithms. In this study we look at improving the efficiency of solving large linear systems that result from two applications. The first includes linear systems that result from solving differential equations for the movement of atomic particles in particle emitting, void, and absorbing regions. The second includes solving linear systems that result from solving differential …