Physical Sciences and Mathematics Commons^™

An Evaluation Of The Productivity Of Two Oil Mallee Species In A Revegetation Trial In The Central Wheatbelt Of Western Australia, Beatrice Lucie Hedwig Franke

Theses : Honours

Two of Western Australia's most pressing land degradation problems are waterlogging and increasing soil salinity. Extensive clearing of the native. deep-rooted vegetation and its replacement with shallow-rooted crop and pasture plants has resulted in increased recharge of groundwater tables. causing them to rise. Salts stored in the soil are being brought to the soil surface with the rising watertables. Revegetation with deep-rooted native plants has been identified as the most likely strategy to achieve increased groundwater usage and a lowering of watertables. One area seriously affected by waterlogging and increasing salinity is the Western Australian central wheatbelt region. The Department …

Does Good Project Management Ensure Successful Software Development?, Julie Lisa Eldridge

Theses : Honours

For many years the development of computer software has been plagued by poor customer satisfaction caused by missed schedules, underestimated budgets and the development of products which do not meet requirements. The ever increasing reliance on computers, as reported by Sommerville ''the result of the proliferation of computer systems into all aspects of life and business is that personal, corporate, national and international economies are [becoming] increasingly dependant on computers and software systems" ( 1992, p.2), calls for more stable software which can be developed within time and budget constraints. To achieve this, software development activities must be analysed and …

Twenty-Five Year Index To The Prairie Naturalist, Volumes 1-25, 1968-1993, Paul B. Kannowski

The Prairie Naturalist

Forward

Author Index

1.Articles and Notes

2. Book Reviews

3. Editorials

Subject Index

Geographic Index

Taxonomic Index

Plants

Animals

Other Records

A System For Collecting Milligram Quantities Of Cloud Condensation Nuclei, Darryl J. Alofs, Donald E. Hagen, Steven D. Medley, Daniel R. White, John L. Schmitt, Allen L. Williams

Mechanical and Aerospace Engineering Faculty Research & Creative Works

An Experimental System to Collect Cloud Condensation Nuclei (CCN) Onto Filters in Amounts Sufficient for Chemical Analysis is Described. This Experimental Apparatus is Designed to Process Ambient Air at a Rate of More Than 1 M3/min. Two Identical Systems Have Been Built. One is Installed in a Laboratory at Rolla, MO. the Other is Installed on an 11 M Long Trailer. the System Isolates Three Size Classes of CCN, Having Mass Median Diameters of 0.27, 0.12, and 0.075 Μm, Respectively, and Mass Collection Rates of 11.5, 1.28, and 0.13 Mg/day, Respectively. the above Sizes and Collection Rates Are Obtained from …

Hoffman’S Error Bounds And Uniform Lipschitz Continuity Of Best L(P) -Approximations, H. Berens, M. Finzel, W. Li, Y. Xu

Mathematics & Statistics Faculty Publications

In a central paper on smoothness of best approximation in 1968 R. Holmes and B. Kripke proved among others that on ℝⁿ, endowed with the l_ρ-norm, 1< p < ∞, the metric projection onto a given linear subspace is Lipschitz continuous where the Lipschitz constant depended on the parameter p. Using Hoffman’s Error Bounds as a principal tool we prove uniform Lipschitz continuity of best l_ρ -ap- proximations. As a consequence, we reprove and prove, respectively, Lipschitz. continuity of the strict best approximation (sba, p = ∞ and of the natural best approximation (nba, p = 1.

Superconvergence Of The Iterated Collocation Methods For Hammerstein Equations, Hideaki Kaneko, Richard D. Noren, Peter A. Padilla

Mathematics & Statistics Faculty Publications

In this paper, we analyse the iterated collocation method for Hammerstein equations with smooth and weakly singular kernels. The paper expands the study which began in [16] concerning the superconvergence of the iterated Galerkin method for Hammerstein equations. We obtain in this paper a similar superconvergence result for the iterated collocation method for Hammerstein equations. We also discuss the discrete collocation method for weakly singular Hammerstein equations. Some discrete collocation methods for Hammerstein equations with smooth kernels were given previously in [3, 18].

Antiplane Shear Of A Strip Containing A Staggered Array Of Rigid Line Inclusions, G. Kerr, G. Melrose, J. Tweed

Mathematics & Statistics Faculty Publications

Motivated by the increased use of fibre-reinforced materials, we illustrate how the effective elastic modulus of an isotropic and homogeneous material can be increased by the insertion of rigid inclusions. Specifically we consider the two-dimensional antiplane shear problem for a strip of material. The strip is reinforced by introducing two sets of ribbon-like, rigid inclusions perpendicular to the faces of the strip. The strip is then subjected to a prescribed uniform displacement difference between its faces, see Figure 1. it should be noted that the problem posed is equivalent to that of the uniform antiplane shear problem for an infinite …

A Dual Approach To Constrained Interpolation From A Convex Subset Of Hilbert Space, Frank Deutsch, Wu Li, Joseph D. Ward

Mathematics & Statistics Faculty Publications

Many interesting and important problems of best approximationare included in (or can be reduced to) one of the followingtype: in a Hilbert spaceX, find the best approximationPK(x) to anyx∈Xfrom the setK≔C∩A−1(b),whereCis a closed convex subset ofX,Ais a bounded linearoperator fromXinto a finite-dimensional Hilbert spaceY, andb∈Y. The main point of this paper is to show thatPK(x)isidenticaltoPC(x+A*y …

The Laws Of Complexity & The Complexity Of Laws: The Implications Of Computational Complexity Theory For The Law, Eric Kades

Faculty Publications

No abstract provided.

Knickpoint Analysis Of Streams In North Dakota, South Dakota, And Nebraska, Trent D. Hubbard

Theses and Dissertations

Analysis of stream profiles, seismic reflection studies, engineering studies, and historical earthquakes indicates uplift in south-central South Dakota and north-central Nebraska over the last 5-10 ma. The purpose of this study was to determine if this uplift could be detected by constructing topographic profiles along, and in close proximity to several streams in this region. The Cannonball River, ND, was used to compare the streams in South Dakota and Nebraska to a stream beyond the affected area.

Data for the profiles were collected from 7 .5 minute topographic maps as well as GPS surveys. Abrupt changes in slope (irregularities) were …

Yield-Per-Recruit Analysis And Management Strategies For Atlantic Croaker, Micropogonias Undulatus, In The Middle Atlantic Bight, Luiz R. Barbieri, Mark E. Chittenden, Cynthia M. Jones

OES Faculty Publications

The effect of different fishing mortality (F) and natural mortality (M), and age at first capture (t(c)) on yield-per-recruit of Atlantic croaker, Micropogonias undulatus, in the lower Chesapeake Bay and North Carolina were evaluated with the Beverton-Holt model. Independent of the level of M (0.20-0.35) or F (0.01-2.0) used in simulations, yield-per-recruit values for Chesapeake Bay were consistently higher at t((c)) = 1 and decreased continuously with increases in t(c) (2-5). Although maximum yield-per-recruit always occurred at the maximum level off (F=2.0), marginal increases in yield beyond F = 0.50-0.75 were negligible. Current F (F(CUR)) is estimated to be …

Response Of Otolith Microchemistry To Environmental Variations Experienced By Larval And Juvenile Atlantic Croaker (Micropogonias Undulatus), Simon R. Thorrold, Cynthia M. Jones, Steven E. Campana

OES Faculty Publications

Minor and trace elements incorporated into otoliths during growth may permanently record environmental conditions experienced by fishes. To determine the validity of this approach, we used laser ablation inductively coupled plasma mass spectrometry (LA-ICPMS) to assay sectioned otoliths from juvenile Atlantic croaker (Micropogonias undulatus) collected from each of three sites in the Neuse River, North Carolina, and the Elizabeth River, Virginia. Elemental concentrations at the center of the otoliths did not differ between locations, although both Mg : Ca and Ba : Ca were significantly higher at the edge of otoliths from the Neuse River than from the …

Destruction Of Chloropigments In Copepod Guts, A. B. Bochdansky, D. Deibel

OES Faculty Publications

In a recent account regarding the destruction of chloropigments within the guts of copepods, Head & Harris (1996) (H&H) presented valuable data on pigment destruction in copepods. However, in one of their main conclusions, the authors invoked 2 enzyme pools to explain the pattern of pigment destruction: one directly derived from copepods, the other one produced by the ingested algae. If this conclusion is correct, it would have tremendous impact on the interpretation of data collected by the gut pigment technique. Estimating ingestion rates of copepods in the field would be very difficult, if not impossible, if pigment destruction was …

Fluxes Of Copper-Complexing Ligands From Estuarine Sediments, Stephen A. Skrabal, John R. Donat, David J. Burdige

OES Faculty Publications

Most studies of the organic complexation of Cu in natural waters have focused on distributions and processes in the water column, where a significant fraction of Cu-complexing ligands may be biologically produced. We present direct evidence for a flux of Cu-complexing ligands from estuarine sediments, demonstrating that sediments are a significant, yet previously unrecognized source of the ligands. Fluxes of Cu-complexing ligands from Chesapeake Bay sediments range from 300 to 1,200 nmol m^-2 d^-1, exceeding fluxes of total dissolved Cu by 3->40-fold, suggesting that any Cu fluxing from the sediments is likely to be organically complexed. …

Regulation Of Algal Blooms In Antarctic Shelf Waters By The Release Of Iron From Melting Sea Ice, Peter N. Sedwick, Giacomo R. Ditullio

OES Faculty Publications

During summer 1995-96, we measured iron in the water column and conducted iron-enrichment bottle-incubation experiments at a station in the central Ross Sea (76°30'S, 170°40'W), first, in the presence of melting sea ice, and 17 days later, in ice-free conditions. We observed a striking temporal change in mixed-layer dissolved iron concentrations at this station, from 0.72-2.3 nM with sea ice present, to 0.16-0.17 nM in ice-free conditions. These changes were accompanied doubling of algal (diatom) biomass. Our incubation experiments suggest that conditions were iron-replete in the presence of sea ice, and iron-deficient in the absence of sea ice. We surmise …

Sagebrush (Artemisia Tridentata) Restoration In Altered Sage Grouse (Centrocercus Urophasianus) Habitat Of The Yakima Training Center In Central Washington, Margaret Ann Pounds

All Master's Theses

The restoration of sagebrush at the Yakima Training Center was studied because it was determined that military training was altering the condition of sage grouse habitat, potentially having a negative impact on the sage grouse population of the installation. The management of sage grouse and its habitat on YTC are a priority for the U.S. Army. The objectives of this study were to identify the issues relevant to sage grouse and the restoration of its habitat on the training facility, to investigate sagebrush restoration techniques, and to make management recommendations based upon this study. Results of this study indicate that …

A Chemical Extraction Study Of Lead Contaminated Soil From Granite City, Il, Yan Zhang

Masters Theses

Granite City, IL, surface soil ( 0-10 cm ) contaminated with lead was studied by both single- and a four-step sequential chemical extraction procedures designed to establish the partitioning, mobility and availability of lead in soil. The five fractions corresponding to the selected extractants were exchangeable, carbonates-bound, Fe-Mn oxides bound, organic matter and residual. Lead contamination of the soil was determined as a function of particle size and soil depth.

The contaminated sample had the highest lead content of 573.1 mg/kg at the 4 cm soil depth level, and on average was about 8.8 times that of background soil. Most …

A Monte Carlo Model Of Uncertainty In A Deterministic Hazardous Waste Transportation Risk Assessment, Michael A. Cowen

Masters Theses

This thesis is aimed at developing and applying advanced modeling tools in the prediction of risk to the general public from transportation of chemical waste on public highways. The modeling tools developed can then be used to compare alternative waste management scenarios. The application considered is related to the transport of hazardous waste generated by the United States Department of Energy (DOE) to current treatment, storage, and disposal facilities. DOE is currently considering four different scenarios.

The application considered can be more specifically defined as an analysis of the risk to the general public from transporting the 63 shipments of …

Matching Numerical Simulations To Continuum Field Theories: A Lattice Renormalization Study, J Borrill, M. Gleiser

Dartmouth Scholarship

The study of nonlinear phenomena in systems with many degrees of freedom often relies on complex numerical simulations. In trying to model realistic situations, these systems may be coupled to an external environment which drives their dynamics. For nonlinear field theories coupled to thermal (or quantum) baths, discrete lattice formulations must be dealt with extreme care if the results of the simulations are to be interpreted in the continuum limit. Using techniques from renormalization theory, a self-consistent method is presented to match lattice results to continuum models. As an application, symmetry restoration in ϕ4 models is investigated.

Computational Studies Of Hydroboration: Remote Functional Groups And Ring Size Effects, Sarah Liberty Olbrich

Honors Theses

This study is a preliminary computational study of the energies of complex molecules. We are looking at the roles of remote heteroatoms in the hydroboration of propellane systems and ring size effects in the solvolysis of cyclic alkyl halides was examined using computational methods. Geometry and transition state optimizations were done using semi empirical (MNDO. AMI) and ab initio (STO-3G, 3-2IG, and 6-31G*) methods. Attempts to correlate computational results with previously reported data will be presented.

Suspended Particulate Matter And Sediment Of Penobscot Estuary, Craig M. Pochini

Honors Theses

An automated scanning electron microscope with an energy dispersive spectrometer was used to gather morphological and chemical information on individual particles from the suspended particulate matter of the Penobscot Estuary and the sediment of Goose Cove/Pond. The goals of the Penobscot Estuary study were to investigate the transport of particles into and through an estuary, the speciation of elements, the abundance of heavy metals, and the background levels of heavy metals. The majority of particles were aluminosilicates originating from a riverine source. Heavy metals were not abundant in the Penobscot Estuary. The objectives of the Goose Cove/Pond study were to …

Four-Wave Mixing And Optical Phase Conjugation In Vertical Cavity Surface Emitting Devices, Gregory J. Vansuch

Theses and Dissertations

Four-wave mixing (FWM), a nonlinear optical process, was investigated in resonant cavity light emitting diodes (RCLEDs) and vertical cavity surface emitting lasers (VCSELs) below lasing threshold. These semiconductor photonic devices consisted of an optical gain region of quantum wells sandwiched between two distributed Bragg reflector (DBR) mirrors. Pump and probe lasers were injected into the devices to generate FWM. The dependence of FWM on bias current, pump laser power, and spectral and spatial separation between pump and probe lasers was investigated experimentally. A computer model of FWM based on the wave and carrier density equations was developed and agreed well …

Response Surface Methodology: An Analytical Method For Locating Migrated Contaminant Sources, Orlando J. Dona Jr.

Theses and Dissertations

The use and storage of hazardous chemicals at U.S. military facilities often adversely affect the groundwater when contaminants infiltrate the subsurface as a result of leaks and accidental spills. These contaminants, if not located and remediated in a relatively short time, may move and settle unpredictably, essentially creating a source some distance from the original leak or spill. An example of this phenomenon is found with migrating dense nonaqueous phase liquid (DNAPL) contaminants. Although various methods for estimating the present day locations of these migrated contaminants are in use, accurately pinpointing the source of contaminants remains a difficult problem in …

An Assessment Of Hydrological Process And Landform Change: Slave River Delta, Northwest Territories, Ronald Brad Hill

Theses and Dissertations (Comprehensive)

The Slave River Delta, 61˚15'N, 113˚30'W, is located at the mouth of the Slave River in the southeast arm of Canada's Great Slave Lake. Although the delta itself lies some 1600 km downstream from the W.A.C. Bennett Dam at Hudson's Hope, British Columbia, the mean annual discharge and sediment load of the Slave River have decreased by 16% and 33% respectively since regulation. Such alterations in the Slave River flow regime have significant implications for the growth of the River Delta since the transfer of sediment to the delta front is one of the most important factors in the landform’s …

Privacy Issues Dealing With Technology : A Review Of The Literature, Kimberly S. Mccoy

Graduate Research Papers

The sophisticated applications of technology are expanding everyday. Unfortunately, so are the many concerns individuals in society are having about their right to privacy. The actual regulations dealing with one's right to privacy has not expand as rapidly as the applications of technology. Individuals using various types of technology are under the assumption their activities are private; however, this is not the case. It does not seem to matter if you are using a computer for communications work, school, or in the "privacy" of your own home, there is absolutely no privacy when dealing with this type of technology.

This …

A Hypermedia Database To Manage World-Wide-Web Documents, Schubert Shou Boon Foo, Ee Peng Lim

Research Collection School Of Computing and Information Systems

The surge of interest in the World-Wide-Web (WWW) with its potential commercial payoff has resulted in an explosion of information as organisations join in to publish and do business on the Internet. A related development, Intranet, which basically uses the same technology to build private corporate WWW-based networks, has emerged to provide cost-effective and efficient groupware and information management solutions for organisations. As a result, the Hyper Text Markup Language (HTML), used for constructing WWW documents, has become a contender for authoring future office documents. With this scenario, this study examines WWW practices and highlights the inadequacy and drawbacks of …

Low-Degree Graph Partitioning Via Local Search With Applications To Constraint Satisfaction, Max Cut, And Coloring, Magnus M. Halldorsson, Hoong Chuin Lau

Research Collection School Of Computing and Information Systems

We present practical algorithms for constructing partitions of graphs into a fixed number of vertex-disjoint subgraphs that satisfy particular degree constraints. We use this in particular to find k-cuts of graphs of maximum degree ∆ that cut at least a k - 1/k (1 + 1/2∆+k-1 ) fraction of the edges, improving previous bounds known. The partitions also apply to constraint networks, for which we give a tight analysis of natural local search heuristics for the maximum constraint satisfaction problem. These partitions also imply efficient approximations for several problems on weighted bounded-degree graphs. In particular, we improve the best performance …

Measurement Of The Spectral Functions Of Vector Current Hadronic Tau Decays, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

A measurement of the spectral functions of non-strange τ vector current final states is presented, using 124 358 τ pairs recorded by the ALEPH detector at LEP during the years 1991 to 1994. The spectral functions of the dominant two- and four-pion τ decay channels are compared to published results of e + e - annihilation experiments via isospin rotation. A combined fit of the pion form factor from τ decays and e + e - data is performed using different parametrizations. The mass and the width of the ρ ±(770) and the ρ 0(770) are separately determined in order …

Measurement Of The Τ Lepton Lifetime With The Three-Dimensional Impact Parameter Method, R. Barate, M. Thulasidas

Research Collection School Of Computing and Information Systems

A new method is presented for the measurement of the mean lepton lifetime using events in which are pair-produced and both's decay to hadrons.

Improved Measurement Of The Bd0 -B̄D0 Oscillation Frequency, D. Buskulic, M. Thulasidas

Research Collection School Of Computing and Information Systems

The time dependence of B0 d {B 0 d oscillations is measured by the ALEPH experiment at LEP, using three techniques, two of which are updates of previous measurements. In all cases the charge of the decaying b quark and its decay time are measured in one hemisphere of the event; the quark charge at production is tagged mainly using the opposite hemisphere. The first method uses the charge correlation between a D and a lepton in the opposite hemisphere; if no lepton is present, the produced quark charge is determined from the hemisphere charges. In the second method, the …