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The Biogeochemistry Of Hydrogen Sulfide: Phytoplankton Production In The Surface Ocean, Russell S. Walsh, Gregory A. Cutter, William M. Dunstan, Joel Radford-Knoery, Jennifer T. Elder

OES Faculty Publications

Hydrogen sulfide can exist in oxic waters in the form of a dissolved gas, dissociated ions, dissolved metal sulfide complexes, and particulate metal sulfides. The sum of the dissolved species is termed total dissolved sulfide (TDS). In addition to the hydrolysis of carbonyl sulfide, it has been speculated that phytoplankton may produce TDS. We present results from preliminary culture studies which demonstrate that phytoplankton produce TDS and particulate acid-volatile sulfide (pAVS). The phylogenetic order of TDS + pAVS production (per unit cell volume) for the oceanic species examined is Synechococcus sp. > Emiliania huxleyi ≈ Pyramimonas obovata > Thalassiosira oceanica. Moreover, …

Dielectric Response Of Ferroelectric Liquid Crystal Cells, Yuri Panarin, Huan Xu, Seamus Mac Lughadha, Jagdish Vij

Articles

No abstract provided.

The World Wide Web And Technology Transfer At Nasa Langley Research Center, Michael L. Nelson, David J. Bianco

Computer Science Faculty Publications

NASA Langley Research Center (LaRC) began using the World Wide Web (WWW) in the summer of 1993, becoming the first NASA installation to provide a Center-wide home page. This coincided with a reorganization of LaRC to provide a more concentrated focus on technology transfer to both aerospace and non-aerospace industry. Use of the WWW and NCSA Mosaic not only provides automated information dissemination, but also allows for the implementation, evolution and integration of many technology transfer applications. This paper describes several of these innovative applications, including the on-line presentation of the entire Technology Opportunities Showcase (TOPS), an industrial partnering showcase …

Influence Of Reduced Leaching On Growth Of Seedlings Of Black Locust Inoculated With Rhizobia, William R. Graves, Sandra R. Anfinson

Journal of the Iowa Academy of Science: JIAS

Seedlings of black locust (Robinia pseudoacacia L.) were inoculated with compatible rhizobia and irrigated twice each week with solution containing either 50 or 150 mg nitrogen/L. Leaching fraction treatments of 0, 0.2, or 0.4 were maintained for 6 weeks. Seedlings supplied 50 mg nitrogen/L grew poorly compared co planes supplied 150 mg nitrogen/L regardless of leaching fraction. Dry masses of shoots and of entire planes were lower for seedlings in the 0 and 0.2 leaching fraction treatments compared with chose in the 0.4 treatment. Neither leaching fraction nor applied nitrogen concentration appeared co affect the number of nodules per plant, …

Initial Reference Models In Local Earthquake Tomography, E. Kissling, W. L. Ellsworth, D. Eberhart-Phillips, U. Kradolfer

United States Geological Survey: Staff Publications

The inverse problem of three-dimensional (3-D) local earthquake tomography is formulated as a linear approximation to a nonlinear function. Thus the solutions obtained and the reliability estimates depend on the initial reference model. Inappropriate models may result in artifacts of significant amplitude. Here, we advocate the application of the same inversion formalism to determine hypocenters and one-dimensiona(1-D) velocity model parameters, including station corrections, as the first step in the 3-D modeling process. We call the resulting velocity model the minimum 1-D model.  For test purposes,  synthetic data set based on the velocity structure of the San Andreas fault zone in …

Effects Of Lithology And Depth On The Permeability Of Core Samples From The Kola And Ktb Drill Holes, C. Morrow, D. Lockner, S. Hickman, M. Rusanov, T. Röckel

United States Geological Survey: Staff Publications

Permeability measurements were conducted on intact core samples from
the Kola drill hole in Russia and the KTB drill hole in Germany. Samples included granodiorite gneisses, basalts and amphibolites from depths up to 11 km. The tests were intended to determine the pressure sensitivity of permeability and to compare the effects of stress relief and thermal microcracking on the matrix permeability of different rock types and similar samples from different depths. The pore pressure P_p was fixed at the estimated in situ pressure assuming a normal hydrostatic gradient;
the confining pressure P_c was varied to produce effective pressures(P …

Rejex-It'" Ag-36 The Gentle Way To Repel Geese From Golf Courses And Other Turf Areas, Peter F. Vogt

Great Plains Wildlife Damage Control Workshop Proceedings

Birds have always been a problem in agriculture, specially for berries and fruits. Farmers and home owners have been fighting these problems with limited success for centuries. However, the problems with birds on turf are relatively new and are not even known by many people. The "Complete Guide to Pest Control" (Ware 1988) does not even mention geese as a pest, or golf courses as an area of bird problems.

Prospects For The Future In Animal Damage Control, Donald Hawthorne

Great Plains Wildlife Damage Control Workshop Proceedings

I am pleased to be here to address a subject that is very special to many of us, one to which I have devoted my entire career. Animal damage control is a controversial component of wildlife management. In the late 1960's and early 70's, many wildlife practitioners tried to divorce themselves from animal damage control activities. In recent years, however, management of wildlife damage is viewed by many as a vital and integral part of wildlife management, whether to protect human interests and safety or to save an endangered species.

Future Extension Programs On Wildlife Damage Management, James E. Miller

Great Plains Wildlife Damage Control Workshop Proceedings

Extension educational programs, in cooperation with other federal and state organizations, significantly contribute to the present status of wildlife damage management as understood by natural resources professionals and the interested public. Although Extension Service, USDA provides national leadership and coordination of programs, most of the effective programs originate at the state and local level Cooperative Extension Service, regardless of the subject matter. This is particularly true in the area of wildlife damage management. For example, a recent compilation of Extension publications and videotapes on wildlife damage management identifies well over 100 titles available throughout the CES System (Ruff, Craven and …

Developing Risk Communication Skills: More Than Damage Management, Deanne Wright

Great Plains Wildlife Damage Control Workshop Proceedings

Risk communication provides a methodology that enables an organization to respond effectively to issues or situations of a controversial nature. It is one important aspect of risk management.

Urban Nuisance Wildlife Control In Kentucky, Thomas G. Barnes

Great Plains Wildlife Damage Control Workshop Proceedings

A variety of factors including increased urbanization, decreased funding for governmental animal damage programs, and increases in some urban wildlife populations have resulted in a greater demand for urban nuisance wildlife control. Historically, this demand was met by Cooperative Extension Service (San Julian 1987), state fish and wildlife agency, or USDA-APHIS-ADC employees (Bollengier 1987). These agencies provided educational materials, consultations, and/or physically removed animals. Recently, there is an increased demand for physical animal removal evidenced by increasing numbers of private pest control operators (PCO) specializing as urban nuisance wildlife control operators (NWCO).

How To Involve Local Communities In Wildlife Damage Control Decision-Malting, Scott R. Craven

Great Plains Wildlife Damage Control Workshop Proceedings

In most cases the impetus for wildlife damage control (ADC) comes from the individual or group victimized by the problem, i.e., the farmers losing crops to migrating waterfowl or the homeowners frustrated with the loss of valuable ornamental plants to marauding deer. These "victims" or "stakeholders" are clearly best positioned to describe the nature and extent of the problem, how they feel about it, and to comment on what action could/should be taken to reduce or end the problem.

Neutron Reflection Interferometry: Physical Principles Of Surface Analysis With Phase Information, Vladimir Gudkov, G. I. Opat, A. G. Klein

Faculty Publications

It is shown that the analysis of surface layers by neutron reflection interferometry is considerably enhanced by performing the reflectometry with phase information. We discuss two methods of providing such information. One method involves physically adding an extra reference layer, whose amplitude and phase are known theoretically. The other uses the Lloyd's mirror configuration, in which a directly propagating ray that interferes with the reflected ray supplies the phase information. The methods have much in common with holography.

Water Current, Volume 25, No. 4, December 1993

Water Current Newsletter

Grew: Politics Change Rationale for Research
From the Director
Husker Harvest Winners
Needs of Research, Editor Differ
Conjunctive Use Conference Focus
1994 Seminars Look at State's Water History
Variety of Voices Heard at Symposium
Research Brief: Comparitve Toxicity of Pyrethroid Insecticides to Terrestrial and Aquatic Insects
Surface Water Management Interest of Faculty Member
Diretory Lists Wetlands Faculty
Scientists Examine Irrigation with Swine Waste Water
Platte River Atlas Examines Multi-Faceted Big Bend Area
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Developing Realistic Cooperative Behaviors For Autonomous Agents In Air Combat Simulation, Dean P. Hipwell

Theses and Dissertations

This thesis investigated, developed and implemented cooperative decision-making behaviors in an air combat simulation by using a knowledge-based system. Knowledge-based systems were well suited for this task because of built- in features such as inference engines and rule-based constructs. This thesis addresses the specific problem of generating autonomous forces for inclusion in the Advanced Research Projects Agency Distributed Interactive Simulation program. Existing autonomous forces implementations lacked flexibility, realistic behaviors, real-time planning and other features. The simulation system in this thesis addresses the problem of realistic behavior by modeling pilot decision processes rather than aircraft platforms. The system is based on …

Collaborative Multimedia Game Environments, Vinod Anupam, Chandrajit L. Bajaj

Department of Computer Science Technical Reports

No abstract provided.

A Study Of Aquifer Sensitivity And Vulnerability In Kalamazoo County, Michigan Based On Hydrogeologic And Agricultural Factors, Steven Douglas Chidester

Masters Theses

Groundwater in Kalamazoo County, Michigan has been impacted by human activities. This study presents a statistical method for predicting aquifer sensitivity/vulnerability within a glacio-hydrogeologic system.

Computerized data including 3620 water well records with partial chemical analyses, soil surveys, land use maps, and hydrogeologic reports were used to quantify aquifer parameters, nitrate-N contaminant concentrations, soil factors, and agricultural practices. Statistical analyses included simple t-tests , correlation, ANOV A, and multiple regression analyses.

The results indicate that there are statistically significant relationships between nitrate-N concentrations and depth of well submergence, well depth, clay thickness, partial clay thickness, land use, and soil slope. …

Separation Of Copper And Iron In Natural Waters By Solid-Phase Extraction, Charles Bui

Masters Theses

A separation scheme has been developed by utilizing Solid-Phase Extraction cartridges in order to isolate and characterize the charge of metals and their complexes in natural waters. These species can be analyzed by Atomic Absorption Spectroscopy (AAS), Inductively Coupled Plasma (ICP), and Ultraviolet-Visible Spectrophotometry (UVVIS).

This separation scheme would permit the determination of the concentration of metals, as well as providing information about the forms in which the metals exist, e.g., charge of metallic complexes.

Synthetic metal complexes were prepared in the laboratory in order to study the separation scheme as well as trying to understand the binding stability of …

Developing A Graphical User Interface To Support A Real-Time Digital Signal Processing System, Jeffrey C. Miller

Theses and Dissertations

A graphical software user interface for a VMEbus-based real-time digital signal processing system was designed. Use, requirements were defined and the Rumbaugh object-oriented analysis and design technique was applied to analyze the requirements and produce an object-oriented design. The software design includes a graphical, mouse- and keyboard driven user interface, specialized hardware driver modules, and operating system interfaces. An implementation plan was also developed to map the design into the C programming language using existing system code, automatically generated code, and newly written code. Based on the implementation plan, a limited software system prototype w successfully developed and demonstrated. The …

Upgrading Biological Treatment Of Wastewater At Dubai’S Plant By A Fixed-Film System, Rashid Ahmed Bin-Fahad

Theses

The wastewater treatment plant in Dubai, with a design capacity of 130,000 m³/d, receives primarily domestic wastewater and employs primary, secondary and tertiary stages of treatment to produce an effluent suitable for reuse in irrigation. Performance of the plant is influenced to a great extent by the success of the secondary aerobic biological treatment stage. This stage comprises the high-rate activated sludge system for removal of carbonaceous organics followed by the biofilter system for removal of nitrogenous material by nitrification. Operational problems have often been experienced at this plant because of increasing sludge solids production and sludge rising …

Spectral Analysis Of The Flow Behavior Of Big Spring, Kings Canyon National Park, California, Linda Urzendowski

UNLV Theses, Dissertations, Professional Papers, and Capstones

Big Spring, the resurgence of a karst aquifer in the Lilburn Cave system (Kings Canyon National Park, California), displays the uncommon phenomena of ebb and flow discharge during periods of high runoff.

Hydrograph analyses indicate that the portion of Lilburn Cave between the Z-Room and Big Spring is primarily a conduit flow aquifer. The power spectra strongly indicate a nonlinear system, with evidence of quasi-linear behavior found on a smaller scale. The transfer and kernel function indicate that no additional significant inputs or outputs to the system exist. The bench-scale model built to simulate the ebb and flow cycles in …

Script-Based Qos Specifications For Multimedia Presentations, Richard Staehli, Jonathan Walpole

Computer Science Faculty Publications and Presentations

Multimedia presentations can convey information not only by the sequence of events but by their timing. The correctness of such presentations thus depends on the timing of events as well as their sequence and content. This paper introduces a formal specification language for playback of real-time presentations. The main contribution of this language is a quality of service (QOS) specification that relaxes resolution and synchronization requirements for playback. Our definitions give a precise meaning to the correctness of a presentation. This specification language will form the basis for a QOS interface for reservation of operating system resources.

Shock Wave Interaction With L-Shaped Structures, Richard C. Miller

Theses and Dissertations

This study investigated the interaction of shock waves with L-shaped structures using the CTH hydrodynamics code developed by Sandia National Laboratories. Computer models of shock waves traveling through air were developed using techniques similar to shock tube experiments. Models of L-shaped buildings were used to determine overpressures achieved by the reflecting shock versus angle of incidence of the shock front. An L-shaped building model rotated 45 degrees to the planar shock front produced the highest reflected overpressure of 9.73 atmospheres in the corner joining the two wings, a value 9.5 times the incident overpressure of 1.02 atmospheres. The same L-shaped …

Vulnerability Assessment Using A Fuzzy Logic Based Method, Richard W. Fleming

Theses and Dissertations

This thesis demonstrates the feasibility of using qualitative analysis methods to evaluate computer security vulnerabilities. Although many risk analysis systems exist, few provide for the adequate analysis of identified vulnerabilities. While the main focus of this thesis is to evaluate computer security vulnerabilities, the methods involved have application in other areas requiring evaluation using qualitative methods. It is proposed, and demonstrated by this thesis, that the use of qualitative analysis using linguistic variables to describe the impact of computer security vulnerabilities is not only feasible, but intrinsically easier to understand and use than quantitative methods.

A Comparison Of No And N20 Production By The Autophic Nitrifier Nitrosomonas Europaea And The Heterotrophic Nitrifier Alcaligenes Faecalis, Iris C. Anderson, Mark Poth, Julie Homstead, David J. Burdige

OES Faculty Publications

Soil microorganisms are important sources of the nitrogen trace gases NO and N₂O for the atmosphere. Present evidence suggests that autotrophic nitrifiers such as Nitrosomonas europaea are the primary producers of NO and N₂O in aerobic soils, whereas denitrifiers such as Pseudomonas spp. or Alcaligenes spp. are responsible for most of the NO and N₂O emissions from anaerobic soils. It has been shown that Alcaligenes faecalis, a bacterium common in both soil and water, is capable of concomitant heterotrophic nitrification and denitrification. This study was undertaken to determine whether heterotrophic nitrification might be …

Anomalous Mesozoic Thermal Regime, Central Appalachian Piedmont: Evidence From Sphene And Zircon Fission-Track Dating, B. P. Kohn, M. E. Wagner, Tim M. Lutz, G. Organist

Earth & Space Sciences Faculty Publications

No abstract provided.

Project Isaac: Building Simulations For Virtual Environments, George Vanĕček, James Cremer

Department of Computer Science Technical Reports

No abstract provided.

The Design And Implementation Of Tripwire: A File System Integrity Checker, Gene H. Kim, Eugene H. Spafford

Department of Computer Science Technical Reports

No abstract provided.

Large-Cell Renormalization-Group Approach To Long-Range Hopping On Energetically Disordered Lattices, B. D. Bookout, Paul Ernest Parris

Physics Faculty Research & Creative Works

We describe an approach for computing the conductivity associated with long-range hopping on energetically disordered lattices. Using a numerically exact supercell procedure we compute the distribution ρL(γ) of block conductances γL associated with conducting cubes of edge length L that are randomly chosen from the disordered system of interest. This distribution of block conductances is then used in a self-consistent numerical calculation to obtain the renormalized bulk conductivity. The approach displays a surprisingly fast approach to the infinite-system limit, allowing finite-size effects to be minimized. In this paper we use this approach to study transport in a series of binary …

Finite-Element Ray Tracing, Yong-Chun Liu

Theses

The interesting acoustic modeling problems often push the practical limits of full-wave models. For instance, in acoustic tomography one needs to be able to predict the propagation of an acoustic pulse for successive realizations of 31) environments. For these types of problems ray methods continue to be attractive because of their speed. Unfortunately, existing codes are prone to a number of implementation difficulties which often degrade their accuracy.

As a result most ray models are actually incapable of producing the ray theoretic result. We discuss a. new method for implementing ray theory that uses a. finite-clement formulation. This method is …