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Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 13, Number 1, January 1997, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

A twelve page newsletter created by the Wright State University College of Engineering and Computer Science that addresses the current affairs of the college.

Faster Ray Tracing Using Adaptive Grids, Thomas W. Sederberg, Krysztof S. Klimaszewski

Faculty Publications

A new hybrid approach is presented which outperforms the regular grid technique in scenes with highly irregular object distributions by a factor of hundreds, and combined with an area interpolator, by a factor of thousands. Much has been said about scene independence of different acceleration techniques and the alleged superiority of one approach over another. Several theoretical and practical studies conducted in the past have led to the same conclusion: a space partitioning method that allows the fastest rendering of one scene often fails with another. Specialization may be the answer. This has always been pursued, consciously or not, in …

On The Dynamic Behaviour Of A Thermoviscoelastic Body In Frictional Contact With A Rigid Obstacle, Kenneth Kuttler, K. T. Andrews, M. Shillor

Faculty Publications

We consider the dynamic behaviour of a thermoviscoelastic body which may come into frictional contact with a rigid obstacle. The frictional contact is modelled by general contact and friction laws which include as special cases the power law normal compliance condition and the corresponding generalization of Coulomb's law of dry friction. The stress-strain constitutive relation is assumed to be of Kelvin-Voigt type and the frictional heat generation on the contact surface is taken into account. In this setting we establish the existence of a solution to a weak version of the energy-elasticity system which consists of a parabolic equation coupled …

Damped Diocotron Quasi-Modes Of Non-Neutral Plasmas And Inviscid Fluids, S. Neil Rasband, Ross L. Spencer

Faculty Publications

Computations of damped diocotron oscillations (quasi-modes) are described for non-neutral plasmas and inviscid fluids. The numerical method implements a suggestion made by Briggs, Daugherty, and Levy some 25 years ago [Phys. Fluids 13, 421 (1970)] to push the branch line that forms the continuum into the complex w-plane by solving the mode equation in the complex r-plane. For the special case of power-law density profiles the calculation finds the same quasi-mode frequencies found recently by Corngold [Phys. Plasmas 2, 620 (1995)]. It is found that the feature of the continuum eigenfunctions which indicates the presence of a nearby quasi-mode is …

Improved Heterogeneous Distance Functions, Tony R. Martinez, D. Randall Wilson

Faculty Publications

Instance-based learning techniques typically handle continuous and linear input values well, but often do not handle nominal input attributes appropriately. The Value Difference Metric (VDM) was designed to find reasonable distance values between nominal attribute values, but it largely ignores continuous attributes, requiring discretization to map continuous values into nominal values. This paper proposes three new heterogeneous distance functions, called the Heterogeneous Value Difference Metric (HVDM), the Interpolated Value Difference Metric (IVDM), and the Windowed Value Difference Metric (WVDM). These new distance functions are designed to handle applications with nominal attributes, continuous attributes, or both. In experiments on 48 applications …

Photothermal Lens Spectrometry Of Homogeneous Fluids With Incoherent White‐Light Excitationusing A Cylindrical Sample Cell, Agnes Chartier, Stephen E. Bialkowski

Stephen E. Bialkowski

A model for photothermal lens signal generation in a cylindrical sample cell under constant irradiance excitation is described and tested. The model is developed with and without the assumption that the sample cell does not change temperature over the irradiation time. In both cases, the photothermal lens is predicted to be parabolic in form with a strength that is independent of sample cell radius. The predicted irradiance independence suggests that incoherent illumination can be used to perform photothermal lens spectroscopy in low-volume cells. Experimental evidence is obtained using a Xe arc lamp to perform photothermal lens spectroscopy in a 6 …

Diffraction Effects In Single‐ And Two‐Laser Photothermal Lens Spectroscopy, Stephen E. Bialkowski, Agnes Chartier

Stephen E. Bialkowski

A simple method for calculating the effects of optical geometry on photothermal lens signals is shown. This method is based on calculating cumulative electric-field phase shifts produced by a series of Gaussian refractive-index perturbations produced by the photothermal effect. Theoretical results are found for both pulsed-laser and continuous Gaussian laser excitation sources and both single- and two-laser apparatuses commonly employed in photothermal lens spectroscopy. The effects of apparatus geometry on the resulting signal are shown. Analytical time-dependent signal results are found for small signals. Analytical pump–probe focus geometry results allow direct optimization for certain conditions. The calculations indicate that the …

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

Faculty Publications

No abstract provided.

Effect Of Oil Pollution On Juvenile And Adult Rabbitfish (Siganus Canaliculatus), Mohammed Abdul Rahim Hassan Al Zarouni

Theses

The possible toxic effect of crude oil and dispersant on the reproduction and performance of common marine fish in the United Arab Emirates coasts were investigated. Adult female and juvenile rabbitfish (Siganus canaliculatus) were exposed to different concentration of Sharjah light crude oil (0, 4, 6 ml crude oil/l) in the presence or absence of 0.3 mI/l Nalfleet dispersant (Maxi-Clean 2) dissolved in sea water. Juvenile fish were exposed to treatments for 3, 6, 9 or 15 days and adult female were treated for 18 days. At the end of each experimental period histopathological changes in the skin, gills, liver …

Evaluation Of Groundwater Quality In Shallow Aquifers Under Cultivated Lands At Al Oha Area, United Arab Emirates, Waleed Nasser Ahmed Bin Braik

Theses

To assess the impact of application of chemical fertilizers in agriculture on the Quaternary aquifer at AI Oha area, United Arab Emirates, 76 groundwater samples were collected during February 1995 - March 1996. Samples were analyzed for major, minor and trace chemical constituents in the Food Control Laboratory, Abu Dhabi.

The Total Dissolved Solids (TDS) of collected samples varied between 500 milligrams per liter (mg/l) in the east and 3,500 mg/l in the west. Except for bicarbonate ion (HC03-), concentration of major cations (Ca²⁺, Mg²⁺, Na⁺ and K⁺) and anions (CO₃^{2- …}

Directed Panspermia. 3. Strategies And Motivations For Seeding Star-Forming Clouds, Michael Noah Mautner

Chemistry Publications

Microbial swarms aimed at star-forming regions of interstellar clouds can seed stellar associations of 10 - 100 young planetary systems. Swarms of millimeter size, milligram packets can be launched by 35 cm solar sails at 5E-4 c, to penetrate interstellar clouds. Selective capture in high-density planetary accretion zones of densities > 1E-17 kg m-3 is achieved by viscous drag. Strategies are evaluated to seed dense cloud cores, or individual protostellar condensations, accretion disks or young planets therein. Targeting the Ophiuchus cloud is described as a model system. The biological content, dispersed in 30 μm, 1E-10 kg capsules of 1E6 freeze-dried microorganisms …

Structure And Magnetism Of Multiphase Sm0.080co0.645fe0.276 Powders, V. G. Harris, M. Liou, B. N. Das, V. M. Browning, J. E. Snyder, M. Rubinstein, S. H. Lawrence, R. Littleton Iii, D. P. Pappas

Physics Publications

A Sm-poor mixture of Fe-substituted Sm₂Co₁₇, having the nominal stoichiometry of Sm_0.080Co_0.645Fe_0.276, was ball-milled to explore the possibility of enhancing its remanence through direct microstructural refinement. With milling, the Sm₂(Co_0.7Fe_0.3)₁₇ compound disassociates to a body-centered-cubic supersaturated SmCoFe solid solution and a residual SmCoFe amorphous phase. Correspondingly, the coercive field values first increase, peaking at 0.83 kOe after 180 min of milling, then decrease with continued milling to

Investigation Of The Statistical And Spatial Distributions Of Mercury Contaminated Fish, Surface Waters And Soils In Arkansas, H. D. Scott, J. M. Mckimmey

Technical Reports

Mercury (Hg) contamination of fish is a widespread problem throughout much of the United States and the world (Louisiana WWW page, 1997). Levels ofHg in fish suffic1ent to exceed the FDA action level of 1 mg kg-1 have been found in many water bodies, including some in Arkansas and Louisiana. As a result of the serious public health ramifications for developing fetuses and for people that subsist on native fish, fish consumption advisories due to Hg contamination have been issued in 29 states. Contamination of surface water bodies by Hg results from deforestation, forest fires, fossil fuels, mining, natural emissions …

Spatial Analysis Of The Cause Of Mercury Contamination Of Fish In Arkansas - A Report Submitted To The Arkansas Mercury Task Force, H. S. Lin, H. D. Scott

Technical Reports

There have been concerns about mercury (Hg) contamination in fish in Arkansas since the discovery of the problem in the Ouachita River in 1992 (Armstrong et aI., 1995). Of the more than 170 lakes and streams sampled by the Mercury Task Force from 1992 through 1994, 23% had fish with Hg concentrations exceeding the FDA Action Level of 1 ppm (Armstrong et aI., 1995). Cause of the fish Hg contamination, however, is unknown. Given the economic, human-health and environmental costs associated with fish Hg contamination, it is critical that the cause of this widely-spread problem be identified. Determination of the …

Iowa Academy Of Science Membership Directory, 1997-98, Iowa Academy Of Science

Iowa Academy of Science Documents

Table of Contents:

Editorial Board, Journal ... 5
Committees ... 6
Sections ... 18
ISTS Regional Directors ... 22
Awards of Merit ... 24
Excellence in Science Teaching Awards ... 25
Past Presidents ... 26
Membership Roster ... 27

Efficient And General Synthesis Of Novel Β-Polyfluoroalkoxy Vinamidinium Salts, Koichiro Kase, Mitsuyoshi Katayama, Takashi Ishihara, Hiroki Yamanaka, John T. Gupton

Chemistry Faculty Publications

Novel β-polyfluoroalkoxy vinamidinium salts 3 and/or 4 were synthesized in good yields by the reaction of N-(2- polyfluoroalkoxy-3 ,3-difluoro-1-propenyI)trimethylammonium iodides (2), prepared from N-(2,3,3-trifluoro-1-propenyl)trimethylammonium iodide (1), with secondary amines in MeCN at 70 °C for 1 h. The salts were also obtainable in comparable yields by the one-pot reaction of 1 with sodium polyfluoroalkoxide followed by treatment with amines.

Vertex-Edge Pseudo-Visibility Graphs: Characterization And Recognition, Joseph O'Rourke, Ileana Streinu

Computer Science: Faculty Publications

We extend the notion of polygon visibility graphs to pseudo-polygons defined on generalized configurations of points. We consider both vertex-to-vertex, as well as vertex-to-edge visibility in pseudo-polygons. We study the characterization and recognition problems for vertex-edge pseudo-visibility graphs. Given a bipartite graph G satisfying three simple properties, which can all be checked in polynomial time, we show that we can define a generalized configuration of points and a pseudo-polygon on it, so that its vertex-edge pseudo-visibility graph is G. This provides a full characterization of vertex-edge pseudo-visibility graphs and a polynomial-time algorithm for the decision problem. It also implies that …

Clusters Of Stars, Ileana Streinu

Computer Science: Faculty Publications

We solve two open problems posed by Goodman and Pollack[GP84] about sets of signed circular permutations (clusters of stars) arising from generalized configurations of points: recognition and efficient reconstruction (drawing). As a biproduct we get an O(n2) space data structure constructible in O(n2) time, representing the order type of a (generalized) configuration of points and from which the orientation of each triple can be found in constant time, a problem posed in [EHN].

State Of Tampa Bay 1996, J.O.R. Johansson

Reports

The amount of phytoplankton present in Tampa Bay waters can be estimated from measurements of the green plant pigment chlorophyll-a. Phytoplankton is one of several major forms of plants that exist in Tampa Bay and most other estuaries. Other major plant types are submerged seagrass, macro-algae and benthic micro-algae. The different plants can be viewed as being in competition with each other for required resources, such as light and nutrients. Studies conducted in urbanized estuaries have shown that excessive loading of nitrogen generally is accompanied by an increase of phytoplankton and macro-algae, including epiphytic and drift macro-algae, and by a …

Variations In The Frequency-Magnitude Distribution With Depth In Two Volcanic Areas: Mount St. Helens, Washington, And Mt. Spurr, Alaska, Stefan Wiemer, Stephen R. Mcnutt

School of Geosciences Faculty and Staff Publications

The frequency-magnitude distribution of earthquakes, characterized using the b-value, is examined as a function of space beneath Mount St. Helens (1988–1996), and Mt. Spurr (1991–1995). At Mount St. Helens, two volumes of anomalously high b (b > 1.3) can be observed at depths of 2.6–3.6 km below the crater floor and below 6.4 km. These anomalies coincide with (1) the depth of vesiculation of ascending magma, and (2) the suggested location of a magma chamber at Mount St. Helens. Study of Mt. Spurr reveals an area of high b-value (b ≥ 1.3) at a depth of about 2.3–4.5 …

Observations At Costa Rican Volcano Offer Clues To Causes Of Eruptions, M. Hagerty, S. Y. Schwartz, M. Protti, Timothy H. Dixon, M. Garcés

School of Geosciences Faculty and Staff Publications

Recent measurements of ground deformation at an active volcano show great promise for elucidating the processes that lead to volcanic eruptions. A long-term effort to continuously monitor ground deformation over a very wide bandwidth using state-of-the-art geodetic, seismic, and acoustic instruments at Arenal Volcano in Costa Rica is producing high-quality recordings of harmonic tremor and explosive events and offers an exciting opportunity to explore possible lunar periodicities in volcanic eruptivity.

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 …

A Modeling Study Of The Effects Of Size- And Depth-Dependent Predation On Larval Survival, Margaret M. Dekshenieks, Eileen E. Hofmann, John M. Klinck, Eric N. Powell

CCPO Publications

The form of the predation pressure experienced by larval stages of marine invertebrates is largely unknown. However, it is believed that the type, timing and rate of larval predation are critical in determining recruitment to adult populations. In this study, a time and depth-dependent model of the growth and behavior of larvae of the Eastern oyster, Crassostrea virginica, was used to investigate the effects of different forms of size-and depth-dependent predation on larval survivorship. The simulated larval survival for a cohort experiencing size-dependent predation showed that the greatest percent of the cohort survived to competent settlement size when the …

Record Of Decision Open Road And Open Motorized Trail Travel Plan, Targhee National Forest, United States Forest Service

All U.S. Government Documents (Utah Regional Depository)

The purpose and need of this Travel Plan is to offer a balanced range of motorized road and trail related recreation opportunities in the Forest that is consistent with the management prescriptions adopted in the Revised Forest Plan. These prescriptions include standards for the miles of open roads and motorized trails allowed per square mile. This Travel Plan shows which roads and trails will remain open to meet these road and trail density standards.

White River Record Of Decision And Approved Resource Management Plan, United States Bureau Of Land Management

All U.S. Government Documents (Utah Regional Depository)

This document records the decisions reached by the Bureau of Land Management (BLM) for managing 1,455,900 of BLM surface estate and 365,000 acres of split mineral estate within the White River Resource Area.

Development Of Constructed Wetlands For The Reuse Of Wastewat R In Semi-Arid Regions, Byung J. Kim, Sherwood C. Reed, Thomas Andrew, Patrick D. Sullivan, U.S. Army Corps Of Engineers

All U.S. Government Documents (Utah Regional Depository)

Hill Air Force Base (AFB), UT, is responsible for the operation and maintenance of the Utah Test and Training Range (UTTR). The range contains waste-water treatment and disposal facilities that consist of two infiltration ponds operated in parallel, followed by an emergency overflow basin that safeguards against unexpectedly high flow rates. A previous evaluation concluded that the existing facilities should be replaced, at a relatively high cost and with no possibility for beneficial water reuse. The U.S. Army Construction Engineering Research Laboratories (USACERL) was requested to further evaluate the system and to identify cost-effective, feasible alternatives. USACERL researchers identified a …

Final Environmental Impact Statement For Management Of The High Uinta Wilderness, Usda Forest Service

All U.S. Government Documents (Utah Regional Depository)

The Final Environmental Impact Statement analyzes four alternatives to amend the Ashley and Wasatch-Cache National Forest Land and Resource Management Plan (Forest Plan) to include Desired Future Condition for mapped Condition Classes with accompanying indicators and standards for the High Uintas Wilderness. The No Action Alternative is analyzed in depth also. Significant issues considered include effects of human overuse on ecosystem components, the extent visitor experience is impacted by rules and regulations, the extent visitor solitude is impacted by other users, structures, and resource impacts, the extent trails meet wilderness objectives, the threat of human and animal waste to water …

Historical Vegetation On National Forest Lands In The Intermountain Region, U.S. Forest Service

All U.S. Government Documents (Utah Regional Depository)

culmination of multiyear effort to summarize information concerning the presettlement vegetative ecology of the national forests in Utah, Nevada, Idaho, and Wyoming.

Hill Air Force Base, Utah, Final Record Of Decision And Responsiveness Summary For Operable Unit 2, Ogden Alc

All U.S. Government Documents (Utah Regional Depository)

This decision document presents the selected remedy for Operable Unit 2 (OU2) at Hill Air Force Base (HAFB), Utah. It was selected in accordance with the Comprehensive Environmental Response, Compensation, and Liability Act of 1980 (CERCLA), as amended by the Superfund Amendments and Reauthorization Act of 1986 (SARA), and to the extent practicable, the National Oil and Hazardous Substances Pollution Contingency Plan (NCP). This decision is based on the Administrative Record for this site. The State of Utah and the U.s. Environmental Protection Agency (EPA) concur with the selected remedy.

Environmental Assessment Brian Head Resort Master Development Plan, United States Forest Service

All U.S. Government Documents (Utah Regional Depository)

This Pre-Decisional Environmental Assessment documents the analysis of the Proposed Action, one action alternative, and the No Action alternative, developed for the Brian Head Resort Master Development Plan Project Area. The Proposed Action and action alternatives considered in detail are consistent with current management direction. Each alternative responds differently to the issues associated with the Proposed Action. The Proposed Action would provide for the acceptance of the Brian Head Resort Master Development Plan (MDP) Proposal that provides for changes to existing facilities and for additional facilities intended to promote the long term viability and use of the committed public and …