Physical Sciences and Mathematics Commons^™

Adoption Of 3-D Virtual Worlds For Education, X. Chen, Keng Siau, Fiona Fui-Hoon Nah

Research Collection School Of Computing and Information Systems

As an emerging phenomenon, virtual world education is rarely researched in MIS literature. With stiff competition among institutions using virtual worlds for education, a legitimate research question is: What factors influence students’ intention to adopt 3-D virtual world environment for their education needs? Drawing on existing technology acceptance models and studies in other IS contexts, we developed a model to predict students’ acceptance of a 3-D virtual world education environment and plan to empirically test the model using survey data collected from college students. From the academic research perspective, studies on the use of the new technology for education will …

Text Cube: Computing Ir Measures For Multidimensional Text Database Analysis, Cindy Xinde Lin, Bolin Ding, Jiawei Han, Feida Zhu, Bo Zhao

Research Collection School Of Computing and Information Systems

Since Jim Gray introduced the concept of ”data cube” in 1997, data cube, associated with online analytical processing (OLAP), has become a driving engine in data warehouse industry. Because the boom of Internet has given rise to an ever increasing amount of text data associated with other multidimensional information, it is natural to propose a data cube model that integrates the power of traditional OLAP and IR techniques for text. In this paper, we propose a Text-Cube model on multidimensional text database and study effective OLAP over such data. Two kinds of hierarchies are distinguishable inside: dimensional hierarchy and term …

Explaining Inferences In Bayesian Networks, Ghim-Eng Yap, Ah-Hwee Tan, Hwee Hwa Pang

Research Collection School Of Computing and Information Systems

While Bayesian network (BN) can achieve accurate predictions even with erroneous or incomplete evidence, explaining the inferences remains a challenge. Existing approaches fall short because they do not exploit variable interactions and cannot account for compensations during inferences. This paper proposes the Explaining BN Inferences (EBI) procedure for explaining how variables interact to reach conclusions. EBI explains the value of a target node in terms of the influential nodes in the target's Markov blanket under specific contexts, where the Markov nodes include the target's parents, children, and the children's other parents. Working back from the target node, EBI shows the …

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

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

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.

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 …

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 …

Assessment Of Exposure And Effects Associated With Polycyclic Aromatic Hydrocarbon Contamination In South Chattanooga, Tennessee, Jessica K. Leet

Masters Theses and Doctoral Dissertations

The southern part of Chattanooga, TN has been subject to dumping of industrial waste for over 100 years. Chattanooga Creek flows north through this area to the Tennessee River. The dumping of coal tar and other industrial waste in this area h as lead to the contamination of Chattanooga Creek and soil of the surrounding floodplains. Many polycyclic aromatic hydrocarbons (PAHs) are found in these areas, specifically the 16 PAHs the EPA and ATSDR consider to be priority pollutants. The close proximity of residents to contaminated sites in southern Chattanooga initiated an assessment of the potential human health risks. The …

Application Of Web Services To A Simulation Framework, Matthew Bennink

All Theses

The Joint Semi-Automated Forces (JSAF) simulator is an excellent tool for military training and a great testbed for new SAF behaviors. However, it has the drawback that behaviors must be ported into its own Finite State Machine (FSM) language. Web Services is a growing technology that seamlessly connects service providers to service consumers. This work attempts to merge these two technologies by modeling SAF behaviors as web services. The JSAF simulator is then modeled as a web service consumer.
This approach allows new Semi-Automated Forces (SAF) behaviors to be developed independently of the simulator, which provides the developer with greater …

Insights Into Biogeophysical Signatures Using Polarization Force Microscopy, Elizabeth Bartosik

All Theses

The success of bioremediation strategies is dependent upon effective monitoring of microorganisms in the subsurface. Induced polarization (IP) may represent a cost-effective, complementary technique to existing borehole-based microbe detection schemes. Recent studies show a significant, yet poorly understood IP effect associated with the presence of bacteria in aqueous and porous media. This effect is believed to be rooted in the physicochemical surface interactions between cells and minerals which we probe using polarization force microscopy. Polarization force experiments were conducted on a hydrated mica surface using the gram positive bacterium Bacillus subtilis and the gram negative bacterium Escherichia coli. On all …

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 …

The Origin Of The 511 Kev Positron Annihilation Emission Morphology, Bethany Johns

All Theses

The 511 keV positron annhilation emission from the Galactic bulge has yet to solely be attributed to any astrophysical source of positrons. The 511 keV line, characteristic of electron-positron annihilation, was discovered in 1970 by Johnson and Haymes [1973] almost 40 years ago. Most recently the INTERnational Gamma-Ray Astrophysical Laboratory (INTEGRAL) [Knodlseder 1997] has measured the annihilation rates of both components of the Galaxy. The bulge and disk annihilation rates are (1.5 ± 0.1) x 10^43 e+ s^-1 and(0.3 ± 0.2) x 10^43 e+ s^-1, respectively. The ratio of the bulge rate to that of the disk ranges from 3-9. …

Tolerance Intervals In Random-Effects Models, Kakotan Sanogo

Theses and Dissertations

In the pharmaceutical setting, it is often necessary to establish the shelf life of a drug product and sometimes suitable to assess the risk of product failure at the desired expiry period. The current statistical methodology use confidence intervals for the predicted mean to establish the expiry period and prediction intervals for a predicted new assay value or a tolerance interval for a proportion of the population for use in a risk assessment. A major concern is that most methodology treat a homogeneous subpopulation, say batch, either as a fixed effect and therefore uses a fixed-effects regression model (Graybill, 1976) …

Annual Pastural Land Condition Report: 2007 / 2008 Financial Year, Department Of Agriculture And Food, Western Australia

Natural resources published reports

The Commissioner of Soil and Land Conservation is required under section 137 (2) of the Land Administration Act 1997 to provide the Pastoral Lands Board with a report on the current condition of land under pastoral leases in the State. This report presents information from the Department of Agriculture and Food’s pastoral lease inspection program for the 2007/2008 financial year.

Pastoral leases cover 36% (89 million hectares) of Western Australia and range from the tropical grasslands in the north through to the arid shrublands in the south, with rainfall ranging from 1,400 mm in the north Kimberley to less than …

Hydrological Characterization Of A Riparian Vegetation Zone Using High Resolution Multi-Spectral Airborne Imagery, Osama Zaki Akasheh

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Middle Rio Grande River (MRGR) is the main source of fresh water for the state of New Mexico. Located in an arid area with scarce local water resources, this has led to extensive diversions of river water to supply the high demand from municipalities and irrigated agricultural activities. The extensive water diversions over the last few decades have affected the composition of the native riparian vegetation by decreasing the area of cottonwood and coyote willow and increasing the spread of invasive species such as Tamarisk and Russian Olives, harmful to the river system, due to their high transpiration rates, …

Understanding Unfolding Change And The Value Of Strategic Unification In Recent Usu Information Technology Functional Realignment, Eric S. Hawley

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This is a qualitative case study of the 2005-2008 Utah State University Information Technology reorganization from the perspective of key change advocates. The study identified and documented the unfolding change process involved in the reorganization in terms of dissatisfaction, executive changes, internal executive strategic planning, implementation and initial impacts, and continuous "in situ" strategic planning. The study also answered a set of supporting concluding questions indicating increased value to the institution in areas of customer service and confidence, organization, financial resources, planning and policy, security, and increased/improved services and service functions.

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.

Optimal Irrigation Management For Sloping, Blocked-End Borders, Jorge Jose Escurra

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A robust mathematical model of one-dimensional flow for sloping, blocked-end border irrigation was developed using the four-point implicit method to solve the Saint-Venant equations, the volume-balance solution method, and the implementation of new algorithms to avoid numerical instability and solution divergence. The model has the capability of successfully simulating all surface irrigation phases in blocked-end borders for a range of inflow rates (0.01 - 0.05 m³/s per m), longitudinal slopes (up to 1.00%), and border lengths (100 - 500 m).

To achieve numerical stability over the specified parameter ranges, the model was divided into three parts: (1) advance-phase …

Application Of Resiliency Theory And Adaptive Cycles As A Framework For Evaluating Change In Amenity-Transition Communities, Scott L. Hoffmann

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In recent decades, many rural, natural resource-dependent communities have experienced ubiquitous and oftentimes substantial economic decline due to downturns in their commodity-oriented industries. In spite of this, communities with access to varying forms of natural capital have experienced an upsurge in activities such as recreation, tourism, second home growth, and retirement in-migration. If managed properly, amenity-oriented development has potential to reverse economic decline by attracting tourists, entrepreneurs, younger and more educated workers, and retirees, and may ultimately generate economic diversification, local growth, and an improved quality of life for residents. While there are literally thousands of potential measures of well-being, …

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 …

Sequence Alignment With Traceback On Reconfigurable Hardware, Scott Lloyd, Quinn O. Snell

Faculty Publications

Biological sequence alignment is an essential tool used in molecular biology and biomedical applications. The growing volume of genetic data and the complexity of sequence alignment present a challenge in obtaining alignment results in a timely manner. Known methods to accelerate alignment on reconfigurable hardware only address sequence comparison, limit the sequence length, or exhibit memory and I/O bottlenecks. A space-efficient, global sequence alignment algorithm and architecture is presented that accelerates the forward scan and traceback in hardware without memory and I/O limitations. With 256 processing elements in FPGA technology, a performance gain over 300 times that of a desktop …

Do The Coefficients Of A Modular Form Really "Encode Arithmetic Data"?, Ken Mcmurdy, Hari Ravindran

Mathematical Sciences Technical Reports (MSTR)

Language and terminology are so critical to the understanding of modern math- ematics that it is often difficult for even very good mathematicians from different fields to discuss their work in any detail. As a result, common phrases often evolve within each discipline which attempt to capture the avor of some impor- tant idea while avoiding technicality and jargon. For example, when algebraic number theorists are asked why they are so interested in modular forms, it has become common to say with enthusiasm that the coefficients of a modular form "encode arithmetic data". If pressed further, one might go on …

Education In The Environment: A Strategy For Continued Interagency Outdoor Education Programming: Quarterly Progress Report: Period Ending November 30, 2008, Environmental Education Strategy For Nevada

Reports (PLI Education)

Highlights of the university’s focused efforts during the past three months include the following:

• Fourteen people are near completion of the Fall Cohort workshop sessions toward partial achievement of the Nevada State Certification in Environmental and Interpretation Certification Program.
• Participation in the Michoacán Cultural Festival (500 people in attendance).
• Participation in the Day of the Dead: Life in Death Festival (over 11,000 in attendance).
• Development planning is near completion for the mobile exhibit program to support and deliver SNAP messages.
• Forever Earth was scheduled for 32 days and benefited 1077 individuals.
• Sixteen Discover Mojave Outdoor World events were conducted for …

Real-Time Automatic Price Prediction For Ebay Online Trading, Ilya Igorevitch Raykhel

Theses and Dissertations

While Machine Learning is one of the most popular research areas in Computer Science, there are still only a few deployed applications intended for use by the general public. We have developed an exemplary application that can be directly applied to eBay trading. Our system predicts how much an item would sell for on eBay based on that item's attributes. We ran our experiments on the eBay laptop category, with prior trades used as training data. The system implements a feature-weighted k-Nearest Neighbor algorithm, using genetic algorithms to determine feature weights. Our results demonstrate an average prediction error of 16%; …

Survey Of Wind Power Potential For Wind-Based Electricity At Makambako, Iringa Tanzania, Rmr Kainkwa

Tanzania Journal of Science

The potential for wind-generated electricity is examined using 22 months wind data collected from a prospective site located in the southern highlands of Tanzania. While the data for the year 2001 was from March to December that of 2002 was for all the twelve months of the year.Characteristics of monthly and annual wind speed and direction are systematically investigated based on hourly time-series data using Windographer software. The Weibull shape factors k corresponding to a height of 50 m were found to be 3.10 and 3.80 while the scale factors c were 11.06 and 12.27 m/s for the years 2001 …

The Performance Of Maize Crop During Acid Amelioration With Organic Residues In Soils Of Mtwara, Tanzania, Ae Majule, Jo Omollo

Tanzania Journal of Science

This study evaluated acid ameliorative potential and their effects on maize growth of four organic residues namely wild spikenard, cordia, cowpea and pigeon peas through incubations with or without sulphur. This was done in order to recommend potential organic residue source that could ameliorate soil acidity associated with sulphur dusting. Increased levels of sulphur in the soils reduced the growth and dry matter yields of maize due to intense acidification while maize growth and dry matter yields in soils which organic residues were incorporated was enhanced. Enhancement in maize performance may be a result of reduced soil acidity due to …

Geochemistry And Nd - Isotopic Composition Of High Silica Rhyolites In The Neoarchaean Musoma-Mara Greenstone Belt, Northern Tanzania: Evidence For The Presence Of Older Continental Crust, S Manya

Tanzania Journal of Science

The high silica rhyolites of the Kibasuka Hill, although volumetrically minor, constitute a part of the greenstone sequence in the northern Musoma-Mara Greenstone Belt (MMGB). They are characterized by high silica contents (63.38 – 81.65 wt %), very low CaO (! 0.05 wt %), variable to unusually high K2O (2.24 – 13.43 wt %) most likely attributed to strong sericite alteration, and their major element composition are similar to those of melts derived from partial melting of metapelites. The samples have very low concentration of the transition elements, Sr (3.13 – 48.4 ppm) and very large negative Europium anomalies (Eu/Eu* …

Occurrence Of Digenean Larvae In Freshwater Snails In The Ruvu Basin, Tanzania, G. Nkwengulila, E. S. P. Kigadye

Tanzania Journal of Science

A survey was carried out on digenean larvae infecting freshwater snails in five habitats in Dar es Salaam, Ruvu and Morogoro. 9424 snails belonging to 12 species from five families were examined for digenean infection from July 1996 – June 1997. 20 morphologically distinguishable cercariae were recovered. Multiple infections were not recorded. While the general prevalence of digeneans in snails was low (3.5%), variations occurred between seasons, among habitats and snail host species. Prevalence was high during the dry season but low in the rain season. Among habitats, highest prevalence was recorded at Kinondoni pond and lowest at Ruvu ponds, …

Absolute Migration Of Pacific Basin Mid-Ocean Ridges Since 85 Ma And Their Tectonic Implications For The Pacific Plate, Dcp Masalu

Tanzania Journal of Science

Mid-ocean ridges are major physiographic features that dominate the world seafloor. Their absolute motion and tectonics are recorded in magnetic lineations they created. The absolute migration of mid-ocean ridges in the Pacific basin since 85 Ma and their tectonic implications was investigated in this work and the results indicates that at about anomaly 21 (47 Ma) theEast Pacific Rise (EPR) and Juan de Fuca ridge experienced an abrupt change in their migration direction that persisted until about anomaly 6 (20 Ma), probably due to changes in subductionzone configuration in the northern Pacific. This may represent a period of tectonic instability …