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Theses/Dissertations

1998

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Articles 301 - 329 of 329

Full-Text Articles in Physical Sciences and Mathematics

Network Security: An Evaluation Of Security Policies And Firewall Implementations, Melanie L. Abbas Jan 1998

Network Security: An Evaluation Of Security Policies And Firewall Implementations, Melanie L. Abbas

Dissertations and Theses @ UNI

This paper begins focusing on network security issues. The areas of physical security, access security, and connection security are explored. Connection security provides the biggest need for improvement in the entire security field. This type of security is managed best with firewall implementations. Various firewall models are discussed.

Software evaluations were performed on three different commercial Internet security tools. The software was compared on the basis of ease of installation, functionality, level of security provided, and output available. In summary, the value of the firewall is dependent on the need to implement a firewall in an organization.

However, a security …


Composition And Environmental Assessment Of Soils From United Arab Emirates, Torfa Alsheba Khames Alsheriani Jan 1998

Composition And Environmental Assessment Of Soils From United Arab Emirates, Torfa Alsheba Khames Alsheriani

Theses

The study focuses on the mineral and chemical composition, the textural characters and environmental assessment of some soils from the UAE. About forty soil samples were collected from AI Ain District and the Eastern Mountain District. Soils in AI Ain and its suburb are strongly influenced by the aeolian sedimentation, while those of the Eastern Mountain are formed in narrow valleys strikingly close to ophiolitic hinterland.

The studied soils· are remarkably impoverished in clay size fraction and clay minerals as well. This is due to the impeded chemical weathering under the prevailing arid climate. Corroborative techniques including X-ray diffraction, infrared …


Usability Of Visual Basic For Parallel Programming On Windows Nt, James Scott Barker Jan 1998

Usability Of Visual Basic For Parallel Programming On Windows Nt, James Scott Barker

Dissertations and Theses

Visual Basic is a very popular language. Many hardware engineers have learned Visual Basic because of its simplicity, but have never learned C or C++. Furthermore, people are choosing not to use C or C++ for business software development, but instead are embracing languages such as Visual Basic. Since one of the goals of the parallel programming community has been to encourage more widespread use of parallelism in software, this body of programming talent needs to be addressed. This thesis intends to prove that Visual Basic can be used for parallel programming, that using it is at least as easy …


Paramagnetic Nuclear Magnetic Resonance (Nmr) Studies On The Calcium Binding Site Of [Alpha]-Lactalbumin, Thomas Kurt Ritter Jan 1998

Paramagnetic Nuclear Magnetic Resonance (Nmr) Studies On The Calcium Binding Site Of [Alpha]-Lactalbumin, Thomas Kurt Ritter

Dissertations and Theses

Paramagnetic NMR has drawn interest as a technique for extending the range of systems that can be investigated. The purpose of this study was to determine whether a combination of paramagnetic two-dimensional and relaxation techniques allows for assigning resonances corresponding to residues forming the metal binding site of proteins in which the metal is coordinated exclusively by amino acid side chains and which have been previously inaccessible to assignment.

α-Lactalbumin (LA) is a calcium binding protein with relatively broad NMR signals; this broadness has prevented complete assignment. LA has been the subject of many studies, because it can form a …


Software Flexibility In A Web Environment, Michael Layng Jan 1998

Software Flexibility In A Web Environment, Michael Layng

Theses : Honours

Flexible software systems are designed to be able to adapt to changes in their environment without the need for programmer intervention. This allows companies and institutions to avoid the cost of hiring a programmer every time a business rule changes or a data structure is modified. The techniques of designing and implementing flexible 3GL software systems have been proven as a means of reducing the high cost of software maintenance caused by the changing of systems requirements. Such systems have been in operation in the European finance sector since the early 1980's. Edith Cowan University is participating in current research …


Reefs As Contributors To The Diversity Of Epiphytic Algal Communities In Seagrass Meadows, B. R. Van Elvan Jan 1998

Reefs As Contributors To The Diversity Of Epiphytic Algal Communities In Seagrass Meadows, B. R. Van Elvan

Theses : Honours

It has recently become dogma that reef systems arc a source of diversity to algal epiphyte communities in adjacent seagrass meadows. While this theory had not been tested, it was often cited as the reason for unexpected results in algal studies and marine pollution monitoring. This study examined whether reefs do in fact contribute to the diversity of seagrass epiphytes by testing the effect of distance from reef on seagrass epiphyte communities. The study was conducted in the vicinity of Carnac and Garden Islands and Parmelia Bank, off the coast of Fremantle, Western Australia. Three habitat types were selected as …


The Synthesis And Characterization Of A Porphyrin Oligomer As A Potential Antenna For Light Harvesting Solar Cells, Tristan Timothy Jenkins Jan 1998

The Synthesis And Characterization Of A Porphyrin Oligomer As A Potential Antenna For Light Harvesting Solar Cells, Tristan Timothy Jenkins

Dissertations and Theses

Mankind's attempts to harvest the sun have resulted in photocells with about 15% overall energy conversion efficiency. The best of these cells consist of a light-sensitive dye attached to a semiconductor. Absorbed light energy is transferred to the semiconductor via the delivery of an excited electron from the dye. Dye electrons are replenished with a redox solution, coupling the dye to the counter electrode.

This research was the beginning of an exploration into some potential improvements in the cell. First of all, the redox solution is a corrosive liquid, and leaks present a problem. A porphyrin oligomer with a TCPP …


Perceptions Of Seagrass Ecosystem Health And Potential Indicators For Monitoring, Nick Wood Jan 1998

Perceptions Of Seagrass Ecosystem Health And Potential Indicators For Monitoring, Nick Wood

Theses : Honours

A range of seagrass characteristics were assessed for potential use as indicators of ecosystem health. Shoot density, shoot width, maximum shoot length, above and below ground biomass, percentage canopy cover, leaf area index, leaf extension rate, meadow productivity, epiphyte biomass, epiphyte species richness, percentage of calcium carbonate in epiphytic material and percentage of nitrogen in leaf tissue were all measured in “healthy~ and unhealthy" Posidonia augustifolia meadows in Cockburn and Warnbro Sounds, from June through to August 1998. A questionnaire was used to determine which meadows researchers and managers in the seagrass ecology field in Perth perceived to be healthy …


Carbon Sequestration Of Two Oil Mallee Species, Eucalyptus Loxophleba Subsp. Lissophloia And Eucalyptus. Kochii Subsp. Plenissima In The Semi-Arid Environment Of The Central Wheatbelt Of Western Australia, Andrew Phillip Mccarthy Jan 1998

Carbon Sequestration Of Two Oil Mallee Species, Eucalyptus Loxophleba Subsp. Lissophloia And Eucalyptus. Kochii Subsp. Plenissima In The Semi-Arid Environment Of The Central Wheatbelt Of Western Australia, Andrew Phillip Mccarthy

Theses : Honours

The planting of "Oil malices" have a number of implications in terms of environmental management within Western Australia. Firstly, the incorporation of perennial trees on a large scale into the agricultural landscape can assist in balancing the hydrological cycle and other land degradation problems (Bird et. al. 1992; Western Australian Salinity Action Plan, 1996). Secondly, harvesting the above-ground biomass can produce an economic return because of the oil contained within the leaves. This oil has the potential to replace ozone damaging solvents (Barton and Knight, J997; Wildy, 1996). Finally, "oil mallees" have the potential to offset greenhouse gas emissions, because …


Stakeholder Attitudes As A Resistance Toward Long-Range Management Of A Threatened Landscape: A Case Study Of Aggregate Use In The Township Of North Dumfries (Ontario), Kim Margaret Horrigan Jan 1998

Stakeholder Attitudes As A Resistance Toward Long-Range Management Of A Threatened Landscape: A Case Study Of Aggregate Use In The Township Of North Dumfries (Ontario), Kim Margaret Horrigan

Theses and Dissertations (Comprehensive)

The Township of North Dumfries is located in the rapidly expanding Municipality of Waterloo. This Township is in close proximity to Kitchener, Waterloo, Cambridge, Guelph, Hamilton, and is halfway between London and Toronto, with the primary east-west Highway 401 running through the Township. It is an unique area in that it is characterized by an abundance of prime agricultural lands, Environmentally Sensitive Policy Areas, and wetlands. In addition, the Township is underlain with a large quantity of good quality glacially derived aggregate materials. Land use conflicts have increased as a result of aggregate developers’ pressures on the resources of this …


Protection Of Wetlands In The Grand River Watershed From Non-Point Source Pollution (Ontario), Marsha Lynn Paley Jan 1998

Protection Of Wetlands In The Grand River Watershed From Non-Point Source Pollution (Ontario), Marsha Lynn Paley

Theses and Dissertations (Comprehensive)

The purpose of this study is to assess the strengths and weaknesses of the municipal official plans to protect provincially evaluated wetlands from activities causing non-point source pollution within the Grand River watershed. An integrated framework for policy analysis involving both an evaluative and normative approach assists in determining the value of wetland protection policies and recommends future actions to guide decision-making on development adjacent to wetlands. Specifically, the objectives include (a) to locate, identify and measure the total wetland area, class and number of wetlands in the Grand River watershed on an upper- and lower-tier municipal basis; (b) to …


Requirement Elicitation For Environmental Life Cycle Processes, Mariam Y. Burmawalla Jan 1998

Requirement Elicitation For Environmental Life Cycle Processes, Mariam Y. Burmawalla

Theses

To develop a user-satisfying product the most essential ingredient is to understand user's needs and expectations from the system. Lack of communication between the user and the developer results in an unsatifying output from the user's point of view. Thus proper understanding between the stakeholder and the developer is the most important requirement during the development of any system.

Requirement elicitation process is one such means of expressing wants and requirements from the system by both the parties. Based on Software Engineering Institute's model, requirement elicitation is a web-based application that allows all the people involved in the system to …


The Determination Of The Potential Of Australian Native Plants To Phytoremediate Lead, Desmond Dev Menon Jan 1998

The Determination Of The Potential Of Australian Native Plants To Phytoremediate Lead, Desmond Dev Menon

Theses : Honours

Industrial activities and natural occurrences of mineral ores can both result in the presence of high concentrations of heavy metals in the soil. These toxic metals have been shown to adversely affect human health and the environment. Currently, three main technologies are being used to solve this problem of soil contamination. These are incineration, landfill construction and physico-chemical treatments. The economic and environmental costs of each of these technologies tend to outweigh the merits of their application, especially where contaminated areas are small. These techniques do not necessarily remove the heavy metals from the soil, and can also inhibit biological …


Comparison Of Median Indicator Kriging With Full Indicator Kriging In The Analysis Of Spatial Data, Donna Hill Jan 1998

Comparison Of Median Indicator Kriging With Full Indicator Kriging In The Analysis Of Spatial Data, Donna Hill

Theses : Honours

In the earth sciences, and particularly in the mining of precious metals, data distributions are often strongly positively skewed. When making decisions on the potential profitability of a gold mine, for example, the high values of the distribution are of particular importance. Indicator kriging provides estimates of cumulative distribution functions from which grade tonnage curves may be calculated. Multiple or full indicator kriging requires a semivariogram to be modelled and a kriging system of equations to be solved for each cut off. This can be time consuming and modelling indicator semivariograms at high cut-offs may be difficult because of the …


The Distribution And Long-Term Change In Banksia Ilicifolia Communities On The Gnangara Mound, Ryan Gurner Jan 1998

The Distribution And Long-Term Change In Banksia Ilicifolia Communities On The Gnangara Mound, Ryan Gurner

Theses : Honours

The Gnangara Mound is a large shallow groundwater aquifer which occurs in the superficial formations bounded by the Swan River, Ellenbrook, Gingin Brook, Moore River and the Indian Ocean on the northern Swan Coastal Plain. To protect terrestrial vegetation on the Gnangara Mound. groundwater levels must be maintained to allow plants access to water which is required for their survival. In areas with a shallow depth to groundwater, studies have shown that groundwater drawdown (reduction of the water table by any processes or factors) has a high potential to impact on the vegetation (Havel. 1968: Aplin. 1976: Heddle. 1980a: Dodd …


The Birds And Habitat Of Kings Park, Bradley W. Cox Jan 1998

The Birds And Habitat Of Kings Park, Bradley W. Cox

Theses : Honours

Kings Park is a large urban park in the centre of Perth with extensive areas of semi-natural bushland. The park is an important refuge for birds in the metropolitan area but is losing species through habitat disturbance. Understanding the way in which birds are related to their habitat helps to understand the effect of habitat disturbance on the bird community. The aim of this project was to generate guidelines which will aid in the management and conservation of birds in the park, through an understanding of the relationship of the birds to their habitat. The avifauna and various habitat factors …


An Experimental Study Into The Effect Of Varying The Join Selectivity Factor On The Performance Of Join Methods In Relational Databases, Ada Mallet Jan 1998

An Experimental Study Into The Effect Of Varying The Join Selectivity Factor On The Performance Of Join Methods In Relational Databases, Ada Mallet

Theses : Honours

Relational database systems use join queries to retrieve data from two relations. Several join methods can be used to execute these queries. This study investigated the effect of varying join selectivity factors on the performance of the join methods. Experiments using the ORACLE environment were set up to measure the performance of three join methods: nested loop join, sort merge join and hash join. The performance was measured in terms of total elapsed time, CPU time and the number of I/O reads. The study found that the hash join performs better than the nested loop and the sort merge under …


Vector Geometry And Applications To Three-Dimensional Computer Graphics, Rory Morrison Jan 1998

Vector Geometry And Applications To Three-Dimensional Computer Graphics, Rory Morrison

Theses : Honours

The mathematics behind algorithms involved in generating three-dimensional images on a computer has stemmed from the analysis of the processes of sight and vision. These processes have been modeled to provide methods of visualising three-dimensional data sets. The applications of such visualisations are varied. This project will study some of the mathematics that IS used in three-dimensional graphics applications


Xanthones As Antimalarial Agents : Binding Interactions Between Heme Analogues And Xanthones, Jane Xu Kelly Jan 1998

Xanthones As Antimalarial Agents : Binding Interactions Between Heme Analogues And Xanthones, Jane Xu Kelly

Dissertations and Theses

Human falciparum malaria is caused by Plasmodium falciparum parasite, which digests host hemoglobin within its food vacuole, releasing toxic heme. P. falciparum detoxifies free heme to hemozoin by polymerization. This process is believed to be the target of most successful antimalarial drugs, chloroquine and quinine, which are now losing their effectiveness due to the spread of multi-drug resistant strains. Xanthones were recognized in the laboratory of Dr. M. Riscoe (Portland VA Medical Center) to bind to heme, preventing heme polymerization [Ignatushchenko, M., Winter R., and Riscoe, M. (1997) FEBS Letters 409, 67].

This thesis reports a study of the interactions …


A Java Implementation Of A Portable Desktop Manager, Scott J. Griswold Jan 1998

A Java Implementation Of A Portable Desktop Manager, Scott J. Griswold

UNF Graduate Theses and Dissertations

Computers equipped with a Graphical User Interface (GUI) and connected to the Internet are common in both the business and educational communities. These computers, using a web browser, easily share programs written in the Java programming language that are able to execute on a variety of heterogeneous machines.

While programs written in many languages will not execute unmodified on different computing platforms because of portability restrictions, Java has overcome these limitations and provides a platform independent language. However, every programming language is limited, and no language provides all the features required for every program. Therefore, creation of any portable program …


Contaminated Communities: A Video Documentary Of The Alberton, Montana Mixed-Chemical Spill And An Analysis Of How Its Effects On Toxics Victims Fits Into A Larger Contamination Framework From A Political Ecology Perspective, Lisa A. Mosca Jan 1998

Contaminated Communities: A Video Documentary Of The Alberton, Montana Mixed-Chemical Spill And An Analysis Of How Its Effects On Toxics Victims Fits Into A Larger Contamination Framework From A Political Ecology Perspective, Lisa A. Mosca

Graduate Student Theses, Dissertations, & Professional Papers

The small rural mountain town of Alberton, MT located 32 miles west of Missoula, MT was the 1996 site of the largest contamination event in railroad history involving a mixture of chemicals. On April 11, 1996 a Montana Rail Link train derailed just west of the town of Alberton, leaking 130,000 pounds of chlorine gas, 17,000 of potassium cresylate (spent oil refinery waste), and 85 dry bulk pounds of sodium chlorate into the Alberton environment. Approximately 1000 people were evacuated from their homes, many for the seventeen day evacuation period that followed. The video documentary project that I embarked on …


A Methodology For The Selection Of A Paradigm Of Reasoning Under Uncertainty In Expert System Development, Vivian Campbell Jan 1998

A Methodology For The Selection Of A Paradigm Of Reasoning Under Uncertainty In Expert System Development, Vivian Campbell

Theses: Doctorates and Masters

The aim of this thesis is to develop a methodology for the selection of a paradigm of reasoning under uncertainty for the expert system developer. This is important since practical information on how to select a paradigm of reasoning under uncertainty is not generally available. The thesis explores the role of uncertainty in an expert system and considers the process of reasoning under uncertainty. The possible sources of uncertainty are investigated and prove to be crucial to some aspects of the methodology. A variety of Uncertainty Management Techniques (UMTs) are considered, including numeric, symbolic and hybrid methods. Considerably more information …


User Response And Organisational Fit For Information Systems In Earth Observation, Jeff Kingwell Jan 1998

User Response And Organisational Fit For Information Systems In Earth Observation, Jeff Kingwell

Theses: Doctorates and Masters

A group of seventy six scientists and data managers in the Australian research agency CSIRO were surveyed to establish their needs and preferences in relation to information systems for Earth observation data. After study of available alternatives, three prototype Earth observation information management systems were installed and the user response was evaluated through interview of fifteen of the group. The prototypes consisted of web-based client servers which permitted users to interrogate databases of Earth observation datasets; to search for information about sensor or satellite performance, and to retrieve data and information products. The chosen systems were CILS, the CEOS (Committee …


Paleosols As Holocene Proxy Climate Indicators, Mclean County, North Dakota, Deborah L. Beck Jan 1998

Paleosols As Holocene Proxy Climate Indicators, Mclean County, North Dakota, Deborah L. Beck

Theses and Dissertations

An exposure with 15 buried A-horizons near Douglas Creek, Lake Sakakawea, central North Dakota, has provided an excellent opportunity for paleoclimate reconstruction. Analyses included texture, stable carbon, radiocarbon, pollen, and phytoliths. The variations in these properties between individual soil horizons served to reconstruct the former environments of each soil horizon.

The paleosols were developed in a sequence of deposits in a mile-long tributary to the Missouri River. The soils are in a shallow valley fill exposed by wave action along the north shore of Lake Sakakawea. The 1996 exposure was up to 4m high and 51.5m wide. There were up …


Coherent Neutral Pion Photoproduction On The Deuteron, David G. Meekins Jan 1998

Coherent Neutral Pion Photoproduction On The Deuteron, David G. Meekins

Dissertations, Theses, and Masters Projects

The differential scattering cross section for the process gd→dp0 was measured, as part of experiment E89-012 at Thomas Jefferson National Accelerator Facility. The experiment was performed in Hall C during the Spring of 1996 as the commissioning experiment for the Hall C cryogenic target. The High Momentum Spectrometer was used to detect the recoil deuteron and no effort was made to detect the p0 or its decay photons. The differential cross section was measured at a number of incident photon energies between 0.8 GeV and 4.0 GeV for the deuteron center-of-mass angles of 90?? and 136??. The data were found …


Biogeography Of Amphi-Atlantic And Amphi-American Fishes: The Scomberomorus Regalis (Scombridae), Strongylura Marina (Belonidae) And Hyporhamphus Unifasciatus (Hemiramphidae) Species Groups, Heidi M. Banford Jan 1998

Biogeography Of Amphi-Atlantic And Amphi-American Fishes: The Scomberomorus Regalis (Scombridae), Strongylura Marina (Belonidae) And Hyporhamphus Unifasciatus (Hemiramphidae) Species Groups, Heidi M. Banford

Dissertations, Theses, and Masters Projects

Phylogenetic and historical biogeographic hypotheses were explored for three groups of teleost fishes that are hypothesized to share a common biogeographic track. Distributed across the eastern Pacific/eastern Atlantic (EP/EA) biogeographic track of Rosen (1975) are the Scomberomorus regalis (Scombridae), Strongylura marina (Belonidae) and Hyporhamphus unifasciatus (Hemiramphidae) species groups comprised of one eastern Atlantic; three, three and four western Atlantic; and two, two and four eastern Pacific species, respectively, for each group. In addition, two species in the Strongylura marina and Hyporhamphus unifasciatus groups, have invaded freshwater drainages of Central and South America. Each of the three species groups were found …


A Framework For Planning Sustainable Development In Coastal Regions: An Island Pilot Project In Croatia, Anamarija Frankic Jan 1998

A Framework For Planning Sustainable Development In Coastal Regions: An Island Pilot Project In Croatia, Anamarija Frankic

Dissertations, Theses, and Masters Projects

There have been few empirical studies demonstrating how sustainable development has been realized in a specific regime. This project developed and tested a framework for comprehensive planning including environmental, social, and economic considerations on the island Cres in the Croatian Coastal Zone. The approach defines sustainable development in coastal regions, and develops a generic framework incorporating biological, geological, chemical, physical, social, and economic factors necessary for sustainable development. The generic framework ensures that planning decisions will be based on environmental concerns of the area. A prime principle of the approach is that any plan must work with the environmental limits …


Wind Interaction With Buoyant Plumes On The Inner Continental Shelf, Sarah E. Rennie Jan 1998

Wind Interaction With Buoyant Plumes On The Inner Continental Shelf, Sarah E. Rennie

Dissertations, Theses, and Masters Projects

The characteristics and effects of intrusions of estuarine outflow over the inner shelf were examined, based on hydrographic and meteorological observations obtained during the "Coastal Ocean Processes" (CoOP'94) field experiment located off the Outer Banks at Duck, North Carolina. The episodic presence of distinct low salinity water masses issuing from the Chesapeake Bay created an intermittent baroclinic coastal current along the North Carolina coast. Under low wind conditions, this current occupied the upper half of the water column within 9 km of the coast. The plume was bounded by a distinct southward-propagating front, a region offshore of high horizontal salinity …


A Study Of 3-Tropylium-1,5-Hexadiene, Elise Noma Hattersley Jan 1998

A Study Of 3-Tropylium-1,5-Hexadiene, Elise Noma Hattersley

Dissertations, Theses, and Masters Projects

No abstract provided.