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2008

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Full-Text Articles in Physical Sciences and Mathematics

Fisheries Research Report No. 182 - A Likelihood Analysis Of Non-Indigenous Marine Species Introduction To Fifteen Ports In Western Australia, Justin I. Mcdonald Dec 2008

Fisheries Research Report No. 182 - A Likelihood Analysis Of Non-Indigenous Marine Species Introduction To Fifteen Ports In Western Australia, Justin I. Mcdonald

Fisheries research reports

As an island continent, Australia is heavily dependent upon maritime transport with over 95% of its imports and exports transported by ship (Australian State of the Environment Committee, 2001). With about one third of Australia’s coastline, Western Australia ranks fourth of the six states and territory in the number of known non-indigenous marine species.

In this study fifteen ports in Western Australia were assessed on the potential for non-indigenous marine species to become introduced through ballast water and biofouling. The overall vesselmediated incursion risk to Western Australian ports was calculated by summing the relative incursion threat posed by visits to …


Making Sense Of Technology Trends In The Information Technology Landscape, Gediminas Adomavicius, Jesse C. Bockstedt, Alok Gupta, Robert J. Kauffman Dec 2008

Making Sense Of Technology Trends In The Information Technology Landscape, Gediminas Adomavicius, Jesse C. Bockstedt, Alok Gupta, Robert J. Kauffman

Research Collection School Of Computing and Information Systems

A major problem for firms making information technology investment decisions is predicting and understanding the effects of future technological developments on the value of present technologies. Failure to adequately address this problem can result in wasted organization resources in acquiring, developing, managing, and training employees in the use of technologies that are short-lived and fail to produce adequate return on investment. The sheer number of available technologies and the complex set of relationships among them make IT landscape analysis extremely challenging. Most IT-consuming firms rely on third parties and suppliers for strategic recommendations on IT investments, which can lead to …


Transformation Of Sulfonamide Antibiotics On Soil Mineral Oxides, Baishu Guo Dec 2008

Transformation Of Sulfonamide Antibiotics On Soil Mineral Oxides, Baishu Guo

All Theses

Determining the occurrence and potential adverse effects of antibiotic pharmaceuticals released into the environment is a critical step towards responsible environmental stewardship. Under aqueous conditions typically found in soils and natural waters, the antibiotic agent sulfamethoxazole (SMX) was transformed in the presence of pyrolusite MnO2 via oxidative pathways. At least 50% loss of SMX was observed after 269 hr in acidic and basic solutions (pH 3-9). A maximum of 100% loss was recorded at pH 3 and 66% loss was recorded at circumneutral pH. Concomitantly, aqueous manganese concentrations increased to around 10 µM at pH 3 and 2 µM at …


Analysis Of Chemical Bonding In Clusters By Means Of The Adaptive Natural Density Partitioning, Dmitry Yu Zubarev Dec 2008

Analysis Of Chemical Bonding In Clusters By Means Of The Adaptive Natural Density Partitioning, Dmitry Yu Zubarev

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Models of chemical bonding are essential for contemporary chemistry. Even the explosive development of the computational resources including, both hardware and software, cannot eliminate necessity of compact, intuitive, and efficient methods of representing chemically relevant information. The Lewis model of chemical bonding, which was proposed eleven years before the formulation of quantum theory and preserves its pivotal role in chemical education and research for more than ninety years, is a vivid example of such a tool. As chemistry shifts to the nanoscale, it is becoming obvious that a certain shift of the paradigms of chemical bonding is inescapable. For example, …


Measurement Of Fine Spatial Scale Ecohydrologic Gradients In A Pinyon-Juniper Ecosystem, Matthew David Madsen Dec 2008

Measurement Of Fine Spatial Scale Ecohydrologic Gradients In A Pinyon-Juniper Ecosystem, Matthew David Madsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

With the dramatic expansion of pinyon-juniper woodlands over the last century, improved understanding of how these woodlands modify infiltration properties is needed, in order for land managers to make informed decisions on how to best manage their specific resources. However, current methods for measuring soil infiltration are often limited by low sample sizes and high experimental error, due to constraints associated with remote, non agricultural settings. This thesis first presents a scheme for automating and calibrating two commercially available infiltrometers, which allows collection of a large number of precise unsaturated infiltration measurements in a relatively short period of time. Secondly, …


The Process Of Tracking In Mathematics In Box Elder School District, Megan Haramoto Bushnell Dec 2008

The Process Of Tracking In Mathematics In Box Elder School District, Megan Haramoto Bushnell

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Educational policymakers have used tracking to instruct students in a variety of subjects, including mathematics. Tracking, which has also been called ability grouping, is a process by which students in the same grade are placed into different classes based on academic ability. Few educators and sociologists have looked at the process by which students are placed in different mathematics tracks. The research design of this study focused on accumulating, evaluating, and reporting the understanding and observations of 12 teachers and 4 counselors as they discussed their knowledge and involvement in the mathematics placement procedures from the intermediate and middle school …


A Three-Dimensional, Time-Dependent Circulation Model Of Utah Lake, Eric V. Callister Dec 2008

A Three-Dimensional, Time-Dependent Circulation Model Of Utah Lake, Eric V. Callister

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Spatial and temporal variations of Utah Lake’s flow field were modeled using the Estuary Lake and Computer Model from the Centre for Water Research (CWR-ELCOM) at the University of Western Australia as part of an effort to increase understanding of the lake’s natural processes in order to restore the lake to its pristine, clear-water state and preserve the habitat of the June sucker, an endangered species. The model was validated using temperature measurements taken by sensors in 2007. The water temperature was a strong function of air temperature and incident short wave radiation, and was influenced to a lesser degree …


Intergranular Phases In Cyclically Annealed Yba2cu3o7-X And Their Implications For Critical Current Densities, Andrew Peter Clarke Dec 2008

Intergranular Phases In Cyclically Annealed Yba2cu3o7-X And Their Implications For Critical Current Densities, Andrew Peter Clarke

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

We report changes in the intergranular material and grain morphology of YBa2Cu3O7-x during cyclic anneals between 780 and 980 ºC in oxygen at atmospheric pressure. Two endothermic reactions were detected: (a) the eutectic reaction of YBa2Cu3O7-x with CuO and BaCuO2 at 900 ºC (enthalpy ∆Ha) and (b) the peritectic reaction of YBa2Cu3O7-x with CuO at 950 ºC (∆Hb). During the first anneal, only reaction (b) is detected, and although it should only occur if there is an excess of CuO, …


Forensic And Anti-Forensic Techniques For Object Linking And Embedding 2 (Ole2)-Formatted Documents, Jason M. Daniels Dec 2008

Forensic And Anti-Forensic Techniques For Object Linking And Embedding 2 (Ole2)-Formatted Documents, Jason M. Daniels

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Common office documents provide significant opportunity for forensic and anti-forensic work. The Object Linking and Embedding 2 (OLE2) specification used primarily by Microsoft’s Office Suite contains unused or dead space regions that can be over written to hide covert channels of communication. This thesis describes a technique to detect those covert channels and also describes a different method of encoding that lowers the probability of detection.

The algorithm developed, called OleDetection, is based on the use of kurtosis and byte frequency distribution statistics to accurately identify OLE2 documents with covert channels. OleDetection is able to correctly identify 99.97 percent of …


Extending F10.7'S Time Resolution To Capture Solar Flare Phenomena, Ariel O. Acebal Dec 2008

Extending F10.7'S Time Resolution To Capture Solar Flare Phenomena, Ariel O. Acebal

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Solar ultraviolet (UV) radiation ionizes the neutral components in the atmosphere, which is partly responsible for the formation of the ionosphere, and contributes to heating of the atmosphere. Solar flares change the solar spectrum at times by several orders of magnitude. These changes modify the Earth's upper atmosphere, causing problems to communication systems and space operations, such as increased satellite drag. Unfortunately, solar UV measurements are limited since they can only be observed with space-based sensors. In order to work around this limitation, the solar radio emissions at a wavelength of 10.7 cm have been used as a proxy for …


Synthetic Complexes Of Relevance To Ni(Ii)-Containing Enzymes, Katarzyna Rudzka Dec 2008

Synthetic Complexes Of Relevance To Ni(Ii)-Containing Enzymes, Katarzyna Rudzka

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The work outlined herein presents an investigation of synthetic model complexes of relevance to the active sites of Ni(II)-containing enzymes, particularly urease, glyoxalase I, and acireductone dioxygenase. The research focuses on studying the structural and reactivity features of nickel complexes with biologically relevant substrates. The anion of acetohydroxamic acid is a well-known inhibitor of urease enzymes, including those isolated from Klebsiella aerogenes and Bacillus pasteurii. A precursor to the acetohydroxamate coordination in ureases is proposed to be an interaction between Ni(II) and acetohydroxamic acid. By using a novel supporting chelate ligand capable of secondary hydrogen bonding interactions a novel …


Threat Perception As A Determinant Of Pro-Environmental Behaviors: Public Involvement In Air Pollution Abatement In Cache Valley, Utah, Joshua D. Marquit Dec 2008

Threat Perception As A Determinant Of Pro-Environmental Behaviors: Public Involvement In Air Pollution Abatement In Cache Valley, Utah, Joshua D. Marquit

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Threat perception related to environmental issues such as air pollution may be a determinant of pro-environmental behaviors. Among the potential threats of air pollution, include the perceived impacts on the psychological, social, and economic wellbeing of a community. Because of rapid increases in population growth, urbanization, and the mountainous landscapes, the American West is extremely susceptible to the adverse impacts of air pollution.

A secondary data analysis was conducted using data from the Air Quality Perception Survey conducted in Cache County, Utah. The survey focused on the public perception of air pollution in Cache County and perceived impact on personal …


Sources And Source Processes Of Organic Nitrogen Aerosols In The Atmosphere, Mark E. Erupe Dec 2008

Sources And Source Processes Of Organic Nitrogen Aerosols In The Atmosphere, Mark E. Erupe

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The research in this dissertation explored the sources and chemistry of organic nitrogen aerosols in the atmosphere. Two approaches were employed: field measurements and laboratory experiments. In order to characterize atmospheric aerosol, two ambient studies were conducted in Cache Valley in Northern Utah during strong winter inversions of 2004 and 2005. The economy of this region is heavily dependent on agriculture. There is also a fast growing urban population. Urban and agricultural emissions, aided by the valley geography and meteorology, led to high concentrations of fine particles that often exceeded the national ambient air quality standards. Aerosol composition was dominated …


Agent-Organized Network Coalition Formation, Levi L. Barton Dec 2008

Agent-Organized Network Coalition Formation, Levi L. Barton

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis presents work based on modeling multi-agent coalition formation in an agent organized network. Agents choose which agents to connect with in the network. Tasks are periodically introduced into the network. Each task is defined by a set of skills that agents must fill. Agents form a coalition to complete a task by either joining an existing coalition a network neighbor belongs to, or by proposing a new coalition for a task no agents have proposed a coalition for. We introduce task patience and strategic task selection and show that they improve the number of successful coalitions agents form. …


Strides Towards Better Application Security, Sathyaraj Balasubramanian Dec 2008

Strides Towards Better Application Security, Sathyaraj Balasubramanian

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Static analysis tools analyze source code for vulnerabilities. However, these types of tools suffer from various problems that limit their effectiveness. This thesis examines these static analysis tools and suggests techniques for making them more efficient at detecting different types of vulnerabilities.

The thesis further analyzes possible causes for these vulnerabilities by examining the source code written by programmers of various categories. Finally, this thesis discusses solutions and techniques to improve general security awareness as well as the importance of secure coding among the students and software developers.


Neural Network Output Feedback Control Of A Quadrotor Uav, Jagannathan Sarangapani, Travis Alan Dierks Dec 2008

Neural Network Output Feedback Control Of A Quadrotor Uav, Jagannathan Sarangapani, Travis Alan Dierks

Electrical and Computer Engineering Faculty Research & Creative Works

A neural network (NN) based output feedback controller for a quadrotor unmanned aerial vehicle (UAV) is proposed. The NNs are utilized in the observer and for generating virtual and actual control inputs, respectively, where the NNs learn the nonlinear dynamics of the UAV online including uncertain nonlinear terms like aerodynamic friction and blade flapping. It is shown using Lyapunov theory that the position, orientation, and velocity tracking errors, the virtual control and observer estimation errors, and the NN weight estimation errors for each NN are all semi-globally uniformly ultimately bounded (SGUUB) in the presence of bounded disturbances and NN functional …


Simulation Modeling Of Karst Aquifer Conduit Evolution And Relations To Climate, John D. Broome Dec 2008

Simulation Modeling Of Karst Aquifer Conduit Evolution And Relations To Climate, John D. Broome

Masters Theses & Specialist Projects

ABSTRACT Karst regions of the world that receive relatively similar amounts of precipitation display a wide variety of landscapes. It has been suggested (Groves and Meiman, 2005) that climates exhibiting larger discrete storm events have more dissolving power and consequently higher rates of conduit growth than climates with more uniform precipitation distributions. To study this concept, a computer program “Cave Growth” was developed that modeled the growth of a cross-section of a cave passage under dynamic flow and chemical conditions. A series of 46 simulation datasets were created to represent different climatic conditions. These simulations had the same total annual …


Water Quality Impacts From Agricultural Land-Use In The Karst Groundwater Basin Of Qingmuguan, Chongqing, China, Ted W. Baker Dec 2008

Water Quality Impacts From Agricultural Land-Use In The Karst Groundwater Basin Of Qingmuguan, Chongqing, China, Ted W. Baker

Masters Theses & Specialist Projects

Karst regions are composed of soluble rock, often limestone, which leads to the formation of fissures, sinkholes and water flow conduits such as caves. Pollutants in karst waters tend to be quickly directed and concentrated into these subsurface conduits. As a result of this and other factors, water resources are especially sensitive to contamination and pollution in karst areas. Pollutant concentrations going into fluvial systems travelling through the subsurface in karst areas are often very similar to the concentrations arriving at outlets such as springs. Areas connected by karst conduit flows must be distinctly determined and special attention should be …


Atrazine Contamination And Suspended Sediment Transport Within Logsdon River, Mammoth Cave, Kentucky, Julie Eileen Schenck Brown Dec 2008

Atrazine Contamination And Suspended Sediment Transport Within Logsdon River, Mammoth Cave, Kentucky, Julie Eileen Schenck Brown

Masters Theses & Specialist Projects

Understanding the potential for karst aquifer contamination by sediment-sorbed pesticides is important for cave conservation efforts in agricultural landscapes. Flow rate, water quality parameters and suspended sediment concentrations were measured in Logsdon River, a ~10km karst conduit within the Turnhole Spring Groundwater Basin of Mammoth Cave National Park to determine characteristics of storm-period transport of sediment-sorbed atrazine through a conduit-flow karst aquifer.

Analysis of two independent precipitation events occurring in the Spring of 2008 from May 2-4 and May 27-29 demonstrated the rapid response of the Logsdon River to precipitation events with detections of atrazine increasing during the initial turbidity …


Watershed Condition Assessment For Little River Canyon National Preserve, Alabama, Nathan Demille Rinehart Dec 2008

Watershed Condition Assessment For Little River Canyon National Preserve, Alabama, Nathan Demille Rinehart

Masters Theses & Specialist Projects

No abstract provided.


The Application Of Electrical Resistivity And Microgravity To Locate Tunnels Along The U.S.-Mexico Border At Calexico, Gina Lee Cesin Dec 2008

The Application Of Electrical Resistivity And Microgravity To Locate Tunnels Along The U.S.-Mexico Border At Calexico, Gina Lee Cesin

Masters Theses & Specialist Projects

No abstract provided.


Planning With Ifalcon: Towards A Neural-Network-Based Bdi Agent Architecture, Budhitama Subagdja, Ah-Hwee Tan Dec 2008

Planning With Ifalcon: Towards A Neural-Network-Based Bdi Agent Architecture, Budhitama Subagdja, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

This paper presents iFALCON, a model of BDI (beliefdesire-intention) agents that is fully realized as a selforganizing neural network architecture. Based on multichannel network model called fusion ART, iFALCON is developed to bridge the gap between a self-organizing neural network that autonomously adapts its knowledge and the BDI agent model that follows explicit descriptions. Novel techniques called gradient encoding are introduced for representing sequences and hierarchical structures to realize plans and the intention structure. This paper shows that a simplified plan representation can be encoded as weighted connections in the neural network through a process of supervised learning. A case …


A Fast Pruned‐Extreme Learning Machine For Classification Problem, Hai-Jun Rong, Yew-Soon Ong, Ah-Hwee Tan, Zexuan Zhu Dec 2008

A Fast Pruned‐Extreme Learning Machine For Classification Problem, Hai-Jun Rong, Yew-Soon Ong, Ah-Hwee Tan, Zexuan Zhu

Research Collection School Of Computing and Information Systems

Extreme learning machine (ELM) represents one of the recent successful approaches in machine learning, particularly for performing pattern classification. One key strength of ELM is the significantly low computational time required for training new classifiers since the weights of the hidden and output nodes are randomly chosen and analytically determined, respectively. In this paper, we address the architectural design of the ELM classifier network, since too few/many hidden nodes employed would lead to underfitting/overfitting issues in pattern classification. In particular, we describe the proposed pruned-ELM (P-ELM) algorithm as a systematic and automated approach for designing ELM classifier network. P-ELM uses …


Tree-Like Spaces With The Fixed-Point Property, Realized As Inverse Limits Of Special Finite Trees, Jennifer Katherine Aust Dec 2008

Tree-Like Spaces With The Fixed-Point Property, Realized As Inverse Limits Of Special Finite Trees, Jennifer Katherine Aust

Masters Theses

In this paper, we explore some properties of inverse limit sequences on sub-spaces of Euclidean n-space. We address some well-known examples, in particular the example by David Bellamy of the "tree-like" continuum that does not have the fixed-point property. We highlight some spaces with the fixed-point property that are between snake-like continua and Bellamy's example in their level of complexity. Specifically, we prove the fixed-point property for inverse limits of limit sequences on the unit interval and on the n-ad (in two configurations), and for inverse limits that can be mapped via a continuous function with small point pre-images to …


Distributing Complementary Resources Across Multiple Periods With Stochastic Demand, Shih-Fen Cheng, John Tajan, Hoong Chuin Lau Dec 2008

Distributing Complementary Resources Across Multiple Periods With Stochastic Demand, Shih-Fen Cheng, John Tajan, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

In this paper, we evaluate whether the robustness of a market mechanism that allocates complementary resources could be improved through the aggregation of time periods in which resources are consumed. In particular, we study a multi-round combinatorial auction that is built on a general equilibrium framework. We adopt the general equilibrium framework and the particular combinatorial auction design from the literature, and we investigate the benefits and the limitation of time-period aggregation when demand-side uncertainties are introduced. By using simulation experiments, we show that under stochastic conditions the performance variation of the process decreases as the time frame length (time …


Chosen-Ciphertext Secure Proxy Re-Encryption Without Pairing, Robert H. Deng, Jian Weng, Shengli Liu, Kefei Chen Dec 2008

Chosen-Ciphertext Secure Proxy Re-Encryption Without Pairing, Robert H. Deng, Jian Weng, Shengli Liu, Kefei Chen

Research Collection School Of Computing and Information Systems

In a proxy re-encryption system, a semi-trusted proxy can convert a ciphertext originally intended for Alice into a ciphertext intended for Bob, without learning the underlying plaintext. Proxy re-encryption has found many practical applications, such as encrypted email forwarding, secure distributed file systems, and outsourced filtering of encrypted spam. In ACM CCS'07, Canetti and Hohenberger presented a proxy re-encryption scheme with chosen-ciphertext security, and left an important open problem to construct a chosen-ciphertext secure proxy re-encryption scheme without pairings. In this paper, we solve this open problem by proposing a new proxy re-encryption scheme without resort to bilinear pairings. Based …


Mobitop: Accessing Hierarchically Organized Georeferenced Multimedia Annotations, Thi Nhu Quynh Kim, Khasfariyati Razikin, Dion Hoe-Lian Goh, Quang Minh Nguyen, Ee Peng Lim Dec 2008

Mobitop: Accessing Hierarchically Organized Georeferenced Multimedia Annotations, Thi Nhu Quynh Kim, Khasfariyati Razikin, Dion Hoe-Lian Goh, Quang Minh Nguyen, Ee Peng Lim

Research Collection School Of Computing and Information Systems

We introduce MobiTOP, a map-based interface for accessing hierarchically organized georeferenced annotations. Each annotation contains multimedia content associated with a location, and users are able to annotate existing annotations, in effect creating a hierarchy.


Efficient Client-To-Client Password Authenticated Key Exchange, Yanjiang Yang, Feng Bao, Robert H. Deng Dec 2008

Efficient Client-To-Client Password Authenticated Key Exchange, Yanjiang Yang, Feng Bao, Robert H. Deng

Research Collection School Of Computing and Information Systems

With the rapid proliferation of client-to-client applications, PAKE (password authenticated key exchange) protocols in the client-to-client setting become increasingly important. In this paper, we propose an efficient client-to client PAKE protocol, which has much better performance than existing generic constructions. We also show that the proposed protocol is secure under a formal security model.


Privacy Engine For Context-Aware Enterprise Application Services, Marion Blount, John Davis, Maria Ebling, William Jerome, Barry Leiba, Xuan Liu, Archan Misra Dec 2008

Privacy Engine For Context-Aware Enterprise Application Services, Marion Blount, John Davis, Maria Ebling, William Jerome, Barry Leiba, Xuan Liu, Archan Misra

Research Collection School Of Computing and Information Systems

Satisfying the varied privacy preferences of individuals, while exposing context data to authorized applications and individuals, remains a major challenge for context-aware computing. This paper describes our experiences in building a middleware component, the context privacy engine (CPE), that enforces a role-based, context-dependent privacy model for enterprise domains. While fundamentally an ACL-based access control scheme, CPE extends the traditional ACL mechanism with usage control and context constraints. This paper focuses on discussing issues related to managing and evaluating context-dependent privacy policies. Extensive experimental studies with a production-grade implementation and real-life context sources demonstrate that the CPE can support a large …


Studies Of The Performance, Stability And Reliability Of Various Configurations Of The Activated Sludge Process At Full-Scale Municipal Wastewater Treatment Plants, Michael A. Redda Dec 2008

Studies Of The Performance, Stability And Reliability Of Various Configurations Of The Activated Sludge Process At Full-Scale Municipal Wastewater Treatment Plants, Michael A. Redda

Earth & Environmental Sciences Dissertations

This research presents a performance, stability and reliability analysis of five configurations of activated sludge process, viz., conventional, contact stabilization, complete mix, extended aeration and sequencing batch reactor. Five years effluent records of carbonaceous biochemical oxygen demand (CBOD5), total suspended solids (TSS) and ammonia nitrogen (NH3-N) were used. The impact of hydraulic load classes (HLCes) and seasons on the performance of configurations were also examined. The Univariate General Linear Model with Tukey's Honestly Significant Difference was employed in the performance and stability studies. Performance was determined based on the observed lowest mean effluent concentrations, while the observed standard deviation from …