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Water Current, Volume 28, No. 3, June 1996 Jun 1996

Water Current, Volume 28, No. 3, June 1996

Water Current Newsletter

Water Resources Tour to Explore Republican River Basin
From the Director: Summer Brings Flurry of Grant-Related Activities
Of Groundwater, Surface Water and Fish, the 94th Nebraska Legislature Adjourns
Water Rights Key Issue for Missouri Basin Tribes
Thorson Defines Challenge for Missouri River Basin
Missouri River Endangered
New Video Features Runoff Pollution
Nebraska Water News
Platte Seminar Video Tapes Available
Directory Lists Nebraska Contacts
Kuzelka Recognized For Groundwater Efforts
Three Respondents Win Water Bottles
Web Site Expanded
Wetlands Hotline Operated by EPA
Sheffield Selected to Achievement Hall
Report Examines Pesticides in Stream
31 Counites to Offer Pesticide Container Recycling


On Mobile Systems And Disconnected Browsing Of Distributed Information, Anupam Joshi, Sanjiva Weerawarana, Elias N. Houstis Jun 1996

On Mobile Systems And Disconnected Browsing Of Distributed Information, Anupam Joshi, Sanjiva Weerawarana, Elias N. Houstis

Department of Computer Science Technical Reports

No abstract provided.


The Clam Approach To Multithreaded Communication On Shared-Memory Multiprocessors: Design And Experiments, Joan Carlos Gomez, Edward Mascarenhas, Vernon J. Rego Jun 1996

The Clam Approach To Multithreaded Communication On Shared-Memory Multiprocessors: Design And Experiments, Joan Carlos Gomez, Edward Mascarenhas, Vernon J. Rego

Department of Computer Science Technical Reports

No abstract provided.


Supporting Search For Reusable Software Objects, T. Isakowitz, Robert J. Kauffman Jun 1996

Supporting Search For Reusable Software Objects, T. Isakowitz, Robert J. Kauffman

Research Collection School Of Computing and Information Systems

Prior research has shown that achieving high levels of software reuse in the presence of repository and object-based computer-aided software engineering (CASE) development methods presents interesting human, managerial and technical challenges. This article presents research that seeks to enhanced software development performance through reuse. We propose automated support for developers who search large repositories for the appropriate reusable software objects. We characterize search for repository objects in terms of a multistage model involving screening, identification, and the subsequent choice between new object construction or reusable object implementation. We propose automated support tools, including ORCA, a software Object Reuse Classification Analyzer, …


Design Of Gradient Index Optical Thin Films, Jeffrey J. Druessel Jun 1996

Design Of Gradient Index Optical Thin Films, Jeffrey J. Druessel

Theses and Dissertations

Gradient index thin films provide greater flexibility for the design of optical coatings than the more conventional 'layer' films. In addition, gradient index films have higher damage thresholds and better adhesion properties. This dissertation presents an enhancement to the existing inverse Fourier transform gradient index design method, and develops a new optimal design method for gradient index films using a generalized Fourier series approach. The inverse Fourier transform method is modified to include use of the phase of the index profile as a variable in rugate filter design. Use of an optimal phase function in Fourier-based filter designs reduces the …


A Robust System For Natural Spoken Dialogue, Eric K. Ringger, James F. Allen, Bradford W. Miller, Teresa Sikorski Jun 1996

A Robust System For Natural Spoken Dialogue, Eric K. Ringger, James F. Allen, Bradford W. Miller, Teresa Sikorski

Faculty Publications

This paper describes a system that leads us to believe in the feasibility of constructing natural spoken dialogue systems in task-oriented domains. It specifically addresses the issue of robust interpretation of speech in the presence of recognition errors. Robustness is achieved by a combination of statistical error post-correction, syntactically- and semantically-driven robust parsing, and extensive use of the dialogue context. We present an evaluation of the system using time-to-completion and the quality of the final solution that suggests that most native speakers of English can use the system successfully with virtually no training.


Application Of Tube Settlers In Secondary Wastewater Treatment, Abdulsalam Mohamed Saleh Kamalpoor Jun 1996

Application Of Tube Settlers In Secondary Wastewater Treatment, Abdulsalam Mohamed Saleh Kamalpoor

Theses

Secondary sedimentation is one of the most commonly used unit operations in wastewater treatment plants. It is customary designed to achieve solids separation from biologically treated effluent through clarification of biological solids and thickening of sludge. As treatment plants receive increasingly high wastewater flow, conventional sedimentation tanks suffer from overloading problems which result in poor performance. Inclined plate settlers, a form of tube settlers, may have good potential in upgrading sedimentation tanks. This study was conducted to examine the possibility of applying inclined plate settlers in secondary sedimentation in order to upgrade conventional rectangular sedimentation tanks and improve their performance. …


Environmental Study Indoor And Outdoor Of The Abu Dhabi Compost Plant, Jaber Eidha S. Aljabri Jun 1996

Environmental Study Indoor And Outdoor Of The Abu Dhabi Compost Plant, Jaber Eidha S. Aljabri

Theses

The transformation of municipal solid waste into compost is of double interest: on the one hand, it helps to avoid the deficiencies of natural manure, and on the other it eliminates this major polluting agent which is increasing progressively as a consequence of rising populations.

Domestic waste produced per person per annum amounts to 730 kg in Abu Dhabi city. Based on a population in 1992 of 574,745, this gives a current daily refuse collection that amounts to 1120 tons. Refuse is reported to contain a high proportion of organic materials and therefore to be suitable for recycling to produce …


Towards Designing A Knowledge-Based Tutoring System : Sql-Tutor As An Example, Gang Zhou May 1996

Towards Designing A Knowledge-Based Tutoring System : Sql-Tutor As An Example, Gang Zhou

Dissertations

A Knowledge-Based Tutoring System, also sometimes called an Intelligent Tutoring System, is a computer based instructional system that uses artificial intelligence techniques to help people learn some subject. The goal of the system is to provide private tutoring to its students based on their different backgrounds, requests, and interests. The system knows what subject materials it should teach, when and how to teach them, and can diagnose the mistakes made by the students and help them correct the mistakes.

The major objective of this dissertation is to investigate and develop a generic framework upon which we can build a Knowledge-Based …


Integrating Hypertext With Information Systems Through Dynamic Mapping, Jiangling Wan May 1996

Integrating Hypertext With Information Systems Through Dynamic Mapping, Jiangling Wan

Dissertations

This dissertation presents a general hypertext model (GHMI) supporting integration of hypertext and information systems through dynamic mapping. Information systems integrated based on this model benefit from hypertext function-alities (such as linking, backtracking, history, guided tours, annotations, etc.) while preserving their own computation capabilities. Although systems supporting integration of hypertext and interface-oriented information systems do exist in hypertext literature, there is no existing model or system effectively supporting integration of hypertext and computation-oriented information systems. GHMI makes its major contributions by both extending and specifying the well-known Dexter Hypertext Reference Model. GHMI extends the Dexter model to overcome its limitations. …


Theory And Design Of Portable Parallel Programs For Heterogeneous Computing Systems And Networks, Ying-Chieh Wu May 1996

Theory And Design Of Portable Parallel Programs For Heterogeneous Computing Systems And Networks, Ying-Chieh Wu

Dissertations

A recurring problem with high-performance computing is that advanced architectures generally achieve only a small fraction of their peak performance on many portions of real applications sets. The Amdahl's law corollary of this is that such architectures often spend most of their time on tasks (codes/algorithms and the data sets upon which they operate) for which they are unsuited. Heterogeneous Computing (HC) is needed in the mid 90's and beyond due to ever increasing super-speed requirements and the number of projects with these requirements. HC is defined as a special form of parallel and distributed computing that performs computations using …


Smith On Krauss, 'The Physics Of Star Trek', Anne Collins Smith May 1996

Smith On Krauss, 'The Physics Of Star Trek', Anne Collins Smith

Faculty Publications

Review of Lawrence M. Krauss.The Physics of Star Trek. New York: Basic Books, 1995. xvi + 188 pp. $20.00(cloth), ISBN 978-0-465-00559-8.

Reviewed by Anne Collins Smith (Austin Community College) Published on H-PCAACA (May, 1996)


Pollution Prevention In The New Jersey Chemical Industry : Motivations And Barriers To Commitment, Judith A. Thornton May 1996

Pollution Prevention In The New Jersey Chemical Industry : Motivations And Barriers To Commitment, Judith A. Thornton

Theses

This study of the New Jersey Chemical Industry identifies the primary elements that lead to or inhibit company commitments to pollution prevention. A direct measure of facility pollution prevention commitment is developed that takes into account: organizational support attributes, past reductions achievements, current methods implementation, process reduction goals, and special environmental initiatives. The "P2 Commitment Index" allows for categorization of facilities so that the needs and interests of varying groups may be differentiated.

Higher level commitments are associated with: establishment of company pollution prevention policy, setting of prioritized facility goals, and measurement and reporting on pollution prevention progress. Facilities at …


Vortex Dynamics And Defects In Simulated Flux Flow, Alan Middleton, Michael Chance Faleski, M. C. Marchetti May 1996

Vortex Dynamics And Defects In Simulated Flux Flow, Alan Middleton, Michael Chance Faleski, M. C. Marchetti

Physics - All Scholarship

We present the results of molecular dynamic simulations of a two-dimensional vortex array driven by a uniform current through random pinning centers at zero temperature. We identify two types of flow of the driven array near the depinning threshold. For weak disorder the flux array contains few dislocation and moves via correlated displacements of patches of vortices in a {\it crinkle} motion. As the disorder strength increases, we observe a crossover to a spatially inhomogeneous regime of {\it plastic} flow, with a very defective vortex array and a channel-like structure of the flowing regions. The two regimes are characterized by …


Distribution Of Ionized And Neutral Halogenated Phenols In An Octanol-Water Membrane Model System, Robert Word May 1996

Distribution Of Ionized And Neutral Halogenated Phenols In An Octanol-Water Membrane Model System, Robert Word

Dissertations and Theses

The accumulation of xenobiotics, such as halogenated phenols, in soils, sediments, and living organisms is primarily a partitioning process between an aquatic and organic phase. It is traditional to use a bulk octanol-water system to model the partitioning of a compound between complex biological lipid membranes and aqueous media. The octanol-water partition coefficient KOW successfully approximates the lipid membrane-water partition coefficient KLipW of neutral compounds. However, the ionized species of substituted phenols were shown to have a higher affinity for lipid membranes than predicted from octanol-water results.

Data on the octanol-water partition coefficients of molecular ions is limited. …


Isolation From Soil Microorganisms That Are Inhibitory To Wheat Seeding Pathogens, Kynita Wilson-Humphrey May 1996

Isolation From Soil Microorganisms That Are Inhibitory To Wheat Seeding Pathogens, Kynita Wilson-Humphrey

McCabe Thesis Collection

Many diseases caused by bacteria, viruses, or fungi are responsible for the ruin of a great number of crops annually. At present, many of these crops are being treated for diseases by synthetic or man-made chemicals. Some of the chemicals have been proved to have adverse effects on the environment, including humans and animals. Very few non-chemical means are available to farmers at this time to control these pathogens. This is due to the fact that many of the means of control have little effect against the pathogens or diseases. This research attempts to isolate microorganisms from the soil which …


Identification Of Optimal Locations For Sampling Ground Water For Pesticides In The Mississippi Delta Region Of Eastern Arkansas, H. S. Lin, H. D. Scott, J. M. Mckimmey May 1996

Identification Of Optimal Locations For Sampling Ground Water For Pesticides In The Mississippi Delta Region Of Eastern Arkansas, H. S. Lin, H. D. Scott, J. M. Mckimmey

Arkansas Water Resources Center Technical Reports

Concerns about the presence of pesticides in the Mississippi River Valley alluvial aquifer in the Arkansas Delta have generated the need to develop a map of ground water vulnerability for this region comprised of approximately 10 million acres. Based on the availability of digital data and the scale of this study. we used a modified Pesticide DRASTIC model in a GRASS GIS environment to identify areas that were physically more sensitive to pesticide contamination than other areas within the Delta. Spatial distribution of pesticide loading was estimated from pesticide application rates in different crops and crop distribution map interpreted from …


Proof Strategies For Hardware Verification, Robert Eastham, Krishnaprasad Thirunarayan May 1996

Proof Strategies For Hardware Verification, Robert Eastham, Krishnaprasad Thirunarayan

Kno.e.sis Publications

Ascertaining correctness of digital hardware designs through simulation does not scale-up for large designs because of the sheer combinatorics of the problem. Formal verification of hardware designs holds promise because its computational complexity is of the order of number of different types of components (and not number of components in the design). This approach requires the specification of the behavior and the design in a formal language, and reason with them using a theorem prover. In this paper we attempt to develop a methodology for writing and using these specifications for some important classes of hardware circuits. We examine digital …


The Interaction Of Intense Laser Pulses With Atomic Clusters, T. Ditmire, Thomas D. Donnelly, A. M. Rubenchik, R. W. Falcone, M. D. Perry May 1996

The Interaction Of Intense Laser Pulses With Atomic Clusters, T. Ditmire, Thomas D. Donnelly, A. M. Rubenchik, R. W. Falcone, M. D. Perry

All HMC Faculty Publications and Research

We examine the interaction of intense, femtosecond laser radiation with the large (50–200 Å) clusters produced in pulsed gas jets. Both experiment and simulation show that the plasmas produced during these interactions exhibit electron temperatures far in excess of that predicted by above-threshold ionization theory for a low-density gas. Efficient heating of the clusters by the laser is followed by rapid expansion of the clusters and long-lived x-ray emission from hot, decaying, underdense plasma.


Polarization Stability And Dynamics In A Model For A Polarization-Isotropic Laser That Goes Beyond Third-Order Lamb Theory, N. B. Abraham, Mark Matlin, R. S. Gioggia May 1996

Polarization Stability And Dynamics In A Model For A Polarization-Isotropic Laser That Goes Beyond Third-Order Lamb Theory, N. B. Abraham, Mark Matlin, R. S. Gioggia

Physics Faculty Research and Scholarship

Instabilities and dynamical pulsations are common features of solutions of a model that includes the material variable dynamics for a laser with a polarization isotropic resonator and with a homogeneously broadened j=1 --> j=0 transition. These resemble in some respects features found in third-order Lamb theories under anisotropic conditions, such as splitting of the optical field into two relatively independent orthogonally polarized modes with different optical frequencies. At higher intensities the amplitudes and frequencies of these modes exhibit such strong coupling that a ''two-mode'' description loses its usefulness or effectiveness. Various periodic attractors with strong intensity and polarization pulsations are …


The Emergence Of Alife, P.D. Quick May 1996

The Emergence Of Alife, P.D. Quick

SWITCH

Interview with Kenneth E. Rinaldo, an artist who is on the Board of Directors of YLEM. Within this interview, many topics are covered, including artificial life, simulations, the meaning of art, spirituality, and television. The interview also goes into the personal work and life of Rinaldo, whose focus includes many of these subjects. Some of the more specific subjects include intelligence without consciousness, the combination of science and art, and Ken Rinaldo’s The Flock, an interactive A-Life sculpture.


Rucker, Rudy Rucker May 1996

Rucker, Rudy Rucker

SWITCH

In this article, Rudy Rucker shares his thoughts on hacking. He summarizes it as normal actions, such as building a car, or kneading clay. He compares hacking to things that are buildable by hand, and views creating computer programs the same way. One of the benefits of creating your own computer programs is that you can customize themn however you want. However customizing software on your own is extremely time consuming. He then goes into further detail about artificial life and how hyperspace works. Hacking bends the cyber reality that we are accustomed to, and modifying programs outside of what …


Chronic Effects Of Baseflow Levels Of Atrazine On Platte River Algae, Karen J. Nelson May 1996

Chronic Effects Of Baseflow Levels Of Atrazine On Platte River Algae, Karen J. Nelson

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


A Color-Based Technique For Measuring Visible Loss For Use In Image Data Communication, Melliyal Annamalai, Aurobindo Sundaram, Bharat Bhargava May 1996

A Color-Based Technique For Measuring Visible Loss For Use In Image Data Communication, Melliyal Annamalai, Aurobindo Sundaram, Bharat Bhargava

Department of Computer Science Technical Reports

No abstract provided.


Application Of Neural Networks To The Non-Destructive Testing Of Aluminum Cans, B. Balasubramaniam, Daniel .. Clair May 1996

Application Of Neural Networks To The Non-Destructive Testing Of Aluminum Cans, B. Balasubramaniam, Daniel .. Clair

Computer Science Technical Reports

Neural Networks are used to c lassify aluminum beverage containers as acceptable or non acceptable, depending upon their wall thicknesses. For each can, the thickness of the wall of the can at different points is measured using a non-destructive, ultra-sound technique. These measureI\}ents are then applied as inputs to the networks and the classification is provided as the output Three architectures, one unsupervised and two supervised, are tested. Their performances are analyzed and compared and the paradigm best suited to the problem is selected.


Gnarled Defined, Rudy Rucker May 1996

Gnarled Defined, Rudy Rucker

SWITCH

The article is a reflection of the author’s conception of the term ‘gnarly’, extending the term’s meaning from its origins in California surfer slang. 'Gnarly' is often used in a colloquial context, however, the author believes that the term is able to be used in an academic field as it pertains to outcomes and results of equations. Discussions towards the application of the term 'gnarly' showcase how it can be used in a scientific, mathematical, and artistic context through seemingly random patterns. In order to be gnarly, things must lie and exist between the realm of orderly and chaotic often …


Characterization Of Spatial And Temporal Anisotropy In Turbulent Mixing Layers Using Optical Techniques, Patrick J. Gardner May 1996

Characterization Of Spatial And Temporal Anisotropy In Turbulent Mixing Layers Using Optical Techniques, Patrick J. Gardner

Theses and Dissertations

The optical aberrations induced by mixing layers of dissimilar gases are recorded and analyzed in order to characterize the spatial and temporal properties of the flow. Laser light was propagated through a mixing layer of Helium and Nitrogen gas, having velocities of 8.5 m/sec and 1.5 m/sec, respectively. The light was propagated in a direction perpendicular to the plane of the mixing layer. The mixing layer was evaluated in two experimental regimes: free turbulent mixing, where the mixing layer spreads into the surrounding air; and channel flow, where the mixing layer is confined to a rectangular channel. The optical perturbations …


A Test Of An Alternate Calibration Matrix For Niosh Method 7300, Robert T. Vitek May 1996

A Test Of An Alternate Calibration Matrix For Niosh Method 7300, Robert T. Vitek

Community & Environmental Health Theses & Dissertations

The purpose of this study was to determine if the analytical results (when determining cadmium, lead, and zinc concentrations) for air sample filters prepared and analyzed according to N:OSH Method 7300, differ significantly, from those obtained when the instrument is calibrated using EPA Method 200.7 acid matrix standards. The null hypothesis was that no statistically significant difference, measured at the 95% confidence level, would exist between results obtained from the two calibration standards. Careful standard and sample preparation, the use of an internal standard, and the application of working standard and working internal standard correction factors served to isolate the …


Extraction, Recovery And Separation Of Some Organic And Inorganic Pollutants By Polyurethane Foams And Other Extracting Agents, Mahboob Hassan Saleh May 1996

Extraction, Recovery And Separation Of Some Organic And Inorganic Pollutants By Polyurethane Foams And Other Extracting Agents, Mahboob Hassan Saleh

Theses

Many substances pollute the marine and air environments but non-biodegradable compounds are the most dangerous. Heavy metals and most of the pesticides are known for their high toxicity. Mercury and lead in particular tend to accumulate in liver and kidney and inhibit the biosynthesis of heme protein because of their affinity for thiol and phosphate containing ligands. Thus, it affects the permeability of the membranes of kidney, liver and brain cells. Soluble inorganic mercury (II) species can be transformed into methylmercury under aerobic conditions by the actions of microorganisms. The target organ of methylmercury in humans is the brain where …


A Survey Of Employees Of The United States Department Of Agriculture's Animal Damage Control Program, Susan A. Schroeder May 1996

A Survey Of Employees Of The United States Department Of Agriculture's Animal Damage Control Program, Susan A. Schroeder

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This study examined the attitudes of employees of the United States Department of Agriculture's Animal Damage Control (ADC) Program. This research examined ADC employees' attitudes about wildlife, the ADC program and ADC employment, wildlife damage management methods, euthanasia and the killing process, and the role of various public and private groups on ADC policy. This study also applied the theory of organizational capture to the ADC program to test its utility in explaining the attitudes and behaviors of employees. Results were based on a survey of ADC employees conducted in January 1995.

Survey responses were analyzed to explore associations between …