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Estimating Groundwater Flow Parameters Using Response Surface Methodology, Leo C. Adams Apr 1994

Estimating Groundwater Flow Parameters Using Response Surface Methodology, Leo C. Adams

Theses and Dissertations

This thesis examined the use of response surface methodology RSM as a parameter estimation technique in the field of groundwater flow modeling. Using RSM, an attempt was made to calibrate three hydraulic parameters porosity, transverse permeability, and rate of recharge of an existing two- dimensional, steady-state flow model. The model simulated groundwater flow for a portion of landfill 10 located on Wright-Patterson Air Force Base, Ohio. The model had previously been calibrated by graphical matching observed water-levels to predicted water-levels. Using the parameter values from the earlier calibration effort as a starting point, a central composite design was developed and …


Studies Of The Effect Of Hydrophobic Filter Packs In Free Product Hydrocarbon Recovery Wells, Stephen J. Shank Apr 1994

Studies Of The Effect Of Hydrophobic Filter Packs In Free Product Hydrocarbon Recovery Wells, Stephen J. Shank

Masters Theses

Most free product hydrocarbon recovery wells are filter packed in order to prevent aquifer material from entering the well and to increase their effective diameter. Historically there are five factors in filter pack designs: grain size, grain shape, mineralogy, uniformity, and the filter pack diameter. Previous laboratory experiments found that filter packs treated with a water repellant chemical could dramatically improve well performance. This adds wettability as a sixth factor.

A desorption experiment was conducted to determine the feasibility of using a chemically treated filter pack in the subsurface. Analytical results of the leachate from the chemically treated sand indicated …


Countering Abuse Of Name-Based Authentication, Christoph L. Schuba, Eugene H. Spafford Apr 1994

Countering Abuse Of Name-Based Authentication, Christoph L. Schuba, Eugene H. Spafford

Department of Computer Science Technical Reports

No abstract provided.


High Energy Coupled Nucleon Tranpsort In One Dimension, Stanley L. Lamkin Apr 1994

High Energy Coupled Nucleon Tranpsort In One Dimension, Stanley L. Lamkin

Physics Theses & Dissertations

The problem of energetic nucleon transport through extended bulk matter is considered in the context of the 'straight ahead' approximation. The applicable form of the Boltzmann transport equation is derived and solved in one dimension. The production term for secondary generation nucleons due to nuclear fragmentation includes 'coupling' of the flux to other types of nucleon projectiles. A physically motivated perturbation series approach is developed to enhance solution convergence. The Boltzmann operator is inverted and the flux is computed using a numerical marching scheme. The secondary production integrals are optimized for second order accuracy using a set of analytical benchmarks. …


Iodate Transformation By Marine Phytoplankton, Ajcharaporn Udomkit Apr 1994

Iodate Transformation By Marine Phytoplankton, Ajcharaporn Udomkit

OES Theses and Dissertations

The speciation and distribution of iodine in the oceans are partly under biological control. Phytoplankton are suspected to mediate the transformation of iodate to iodide via reduction by the enzyme nitrate reductase. However, there has been no direct evidence to support this hypothesis.

The influence of phytoplankton on the speciation of iodine was examined with emphasis on the transformation of iodate to iodide. Six cultures of marine phytoplankton: Skeletonema costatum, Dunaliella tertiolecta, Amphidinium carterae, Tetraselmis levis, Emiliania huxleyi, and Synechococcus sp. , have been examined for their ability to take up and reduce iodate under a reduced nitrate environment. In …


Global Picture Archiving And Communication Systems (Gpacs): An Overview, Russell C. Ellis Apr 1994

Global Picture Archiving And Communication Systems (Gpacs): An Overview, Russell C. Ellis

Theses and Dissertations

The world is currently experiencing a computer revolution. With the expansion and development of new computer technology, the age of video is upon us. The medical world is also currently undergoing a dramatic change. With the development and perfection of non-invasive techniques of probing the body, large amounts of computer data is collected and much of it is used to generate images. The organization and management of these images is the topic of this thesis. The discussion of storage schemes, databases, communications and data compression techniques gives the reader a background and some insight to the current state of the …


Retrieval Of Sizes And Total Masses Of Particles In Volcanic Clouds Using Avhrr Bands 4 And 5, Shiming Wen, William I. Rose Mar 1994

Retrieval Of Sizes And Total Masses Of Particles In Volcanic Clouds Using Avhrr Bands 4 And 5, Shiming Wen, William I. Rose

Department of Geological and Mining Engineering and Sciences Publications

The advanced very high resolution radiometer (AVHRR) sensor on polar orbiting NOAA satellites can discriminate between volcanic clouds and meteorological clouds using two-band data in the thermal infrared. This paper is aimed at developing a retrieval of the particle sizes, optical depth, and total masses of particles from AVHRR two-band data of volcanic clouds. Radiative transfer calculations are used with a semi-transparent cloud model that is based on assumptions of spherical particle shape, a homogeneous underlying surface, and a simple thin cloud parallel to the surface. The model is applied to observed AVHRR data from a 13-hour old drifting cloud …


A Topology-Aware Collision Resolution Algorithm, Lewis Barnett Iii Mar 1994

A Topology-Aware Collision Resolution Algorithm, Lewis Barnett Iii

Department of Math & Statistics Technical Report Series

A new collision resolution algorithm called the Space Division Multiple Access protocol (SDMA) is presented. SDMA gains a performance advantage over similar protocols by using information about the positions of stations on the network. The protocol can operate asynchrononsly on a broadcast bus, allowing variable sized packet traffic. Through simulation the protocol is demonstrated to have better performance than Ethernet and the Capetanakis Tree protocol, a similar collision resolution protocol, under some traffic conditions. In particular, under heavy loads, SDMA displays better average throughput and lower variance of delay than Ethernet. The protocol demonstrates a performance bias based on the …


A Study Of Distributed Transaction Processing In Wide Area Network, Bharat Bhargava, Yongguang Zhang Mar 1994

A Study Of Distributed Transaction Processing In Wide Area Network, Bharat Bhargava, Yongguang Zhang

Department of Computer Science Technical Reports

No abstract provided.


Writing, Supporting, And Evaluating Tripwire: A Publically Available Security Tool, Gene H. Kim, Eugene H. Spafford Mar 1994

Writing, Supporting, And Evaluating Tripwire: A Publically Available Security Tool, Gene H. Kim, Eugene H. Spafford

Department of Computer Science Technical Reports

No abstract provided.


The Effective Use Of Animation In Simulation Model Validation, Christopher L. Swider Mar 1994

The Effective Use Of Animation In Simulation Model Validation, Christopher L. Swider

Theses and Dissertations

This study examined two animation displays moving icons, bar graphs at two presentation speeds to determine how each of these factors affected the animations ability to communicate violations of model assumptions. Subjects viewed animation displays individually and in combination at each presentation speed. Eight problem scenarios were presented to evaluate each animations ability to communicate violations of different assumptions. Each animations communication ability was measured subjectively and objectively. Subjective measures in the form of pairwise comparisons were used to calculate normalized preference ratings for each animation. objective measures included problem identification accuracy and problem time. Subjective results indicated that moving …


An Investigation Of Simulated Annealing Applied To Structural Optimization Problems, Richard C. Mceachin Mar 1994

An Investigation Of Simulated Annealing Applied To Structural Optimization Problems, Richard C. Mceachin

Theses and Dissertations

This thesis investigates the feasibility of using Simulated Annealing SA in structural optimization problems. The investigation involves solving benchmark structural optimization problems with an SA algorithm, and comparing its solutions to those found by four other optimizers. Overall, the analysis shows that SA has limited applicability in structural optimization. Two primary factors were found to adversely impact the performance of the SA algorithm in these problems. These factors are high dimensionality, and high levels of constraint. The difficulty involved in solving these problems with a random search increases exponentially with the number of dimensions. The number, and non-linearity, of the …


Policy Considerations For Contraception In Wildlife Management, Wendy A. Sanborn, Robert H. Schmidt, Herbert C. Freeman Feb 1994

Policy Considerations For Contraception In Wildlife Management, Wendy A. Sanborn, Robert H. Schmidt, Herbert C. Freeman

Vertebrate Pest Conference Proceedings: 16th (1994)

Managing wildlife populations by manipulating their birth rates is a promising technology. However, the use of contraceptive technologies will involve the development of new wildlife management policies. We designed and implemented a survey that was intended to gather information on the range of perspectives of concerned publics on contraceptive use in wildlife management. There appears to be considerable confusion and mistrust regarding the application and appropriateness of this new technology. We recommend that promoters of contraception use in wildlife management be careful to explain what this new technology can and cannot do in order to avoid the pitfalls associated with …


Supplemental Bear Feeding Program In Western Washington, Georg J. Ziegltrum Feb 1994

Supplemental Bear Feeding Program In Western Washington, Georg J. Ziegltrum

Vertebrate Pest Conference Proceedings: 16th (1994)

Black bear (Ursus americanus) damage to trees is a severe problem in the Pacific Northwest. Significant damage has been observed for many years, especially in highly managed private industrial forests in western Washington. The introduction of intensive silvicultural techniques resulted in higher yields, but may have also made trees more vulnerable to black bear destruction. Early lethal control efforts lost public support and the forest products industry investigated different methods that concentrated on non-lethal management tools. In 1985, the Washington Forest Protection Association introduced supplemental bear feeding as a damage prevention program in high damage areas during the …


Using Geographic Information Systems For Tracking An Urban Rodent Control Program, Matt Von Wahlde, Bruce A. Colvin Feb 1994

Using Geographic Information Systems For Tracking An Urban Rodent Control Program, Matt Von Wahlde, Bruce A. Colvin

Vertebrate Pest Conference Proceedings: 16th (1994)

Geographic information system technology is being used to help coordinate an urban rodent control program initiated as part of the Central Artery/Tunnel Project in Boston. Databases with neighborhood survey data, surface and subsurface baiting data, sanitation code violations, and public complaints are linked to base mapping, land parcel, and utility graphics. This integrated approach helps Project biologists plan control strategies and evaluate the relatedness of rodent activity to environmental conditions. Spatial querying techniques and the ability to graphically display and map variables, such as bait stations and sanitation deficiencies, help ensure that control resources are effectively targeted and tracked. This …


Registration Requirements For Non-Toxic Natural Products As Animal Damage Control Agents, Stephen A. Schumake Feb 1994

Registration Requirements For Non-Toxic Natural Products As Animal Damage Control Agents, Stephen A. Schumake

Vertebrate Pest Conference Proceedings: 16th (1994)

Plant extracts, animal glandular secretions and excretions, and natural food flavoring agents are common sources of natural products that can be used in animal damage control applications. Such products can be used either by themselves (e.g., coyote urine as a rodent repellent), or in combination with other control agents (e.g., food odor or flavor enhancer at baiting sites). The Environmental Protection Agency registration requirements are described for a variety of potential applications of natural products including bird and rodent repellents. In some applications, the product chemistry or other data requirements could make the registration process prohibitive due to the cost …


Wolf Depredation Management In Relation To Wolf Recovery, Carter C. Niemeyer, E.E. Bangs, S.H. Fritts, J.A. Fontaine, M.D. Jimenez, W.G. Brewster Feb 1994

Wolf Depredation Management In Relation To Wolf Recovery, Carter C. Niemeyer, E.E. Bangs, S.H. Fritts, J.A. Fontaine, M.D. Jimenez, W.G. Brewster

Vertebrate Pest Conference Proceedings: 16th (1994)

By 1930, wolves were extirpated from the western United States for livestock protection. In 1973, the Endangered Species Act protected wolves, and by 1980, wolf recolonization began in Montana. Confirmed livestock losses have been 17 cattle and 12 sheep with 16 wolves controlled as part of a program to enhance the recovery of non-offending wolves. ADC has: 1) controlled problem wolves, 2) improved communication with affected publics and governmental agencies, and 3) enhanced wolf recovery in Montana.


What Do Animal Activists Want? (And How Should Wildlife Managers Respond?), Jon K. Hooper Phd. Feb 1994

What Do Animal Activists Want? (And How Should Wildlife Managers Respond?), Jon K. Hooper Phd.

Vertebrate Pest Conference Proceedings: 16th (1994)

National animal activist organization leaders were interviewed with the aim of better understanding their ideologies with respect to wildlife issues. Interviewees expressed considerable concern about traditional wildlife management practices and associated consumptive recreation activities. They easily identified a number of needed changes, while had difficulty identifying things they liked about the status quo. The top suggested changes related to using more nonlethal management methods and reducing allegiance with consumptive users. The most common "bottom line" concern expressed by interviewees was the alleviation or elimination of unnecessary pain and suffering in wildlife.


Charting A Future: Process And Promise, Bobby R. Acord, Craig A. Ramey, Robert W. Werge Feb 1994

Charting A Future: Process And Promise, Bobby R. Acord, Craig A. Ramey, Robert W. Werge

Vertebrate Pest Conference Proceedings: 16th (1994)

The Animal Damage Control program has been heavily involved in strategic planning since its transfer from USDI to USDA. The first effort was undertaken in 1989 by the program's management team. It was an introspective, critical look at what changes were needed to improve the program's strategic position in the natural resources community. That plan failed to achieve the desired objective due principally to the lack of involvement by ADC employees and others outside the program. In 1991, a more comprehensive effort was begun known as "Futuring." In this process, a representative from each organizational level of the program and …


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 10, Number 2, February 1994, College Of Engineering And Computer Science, Wright State University Feb 1994

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, Volume 10, Number 2, February 1994, 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.


Mathematics And The Arts: Taking Their Resemblances Seriously, Frederick Reiner Feb 1994

Mathematics And The Arts: Taking Their Resemblances Seriously, Frederick Reiner

Humanistic Mathematics Network Journal

No abstract provided.


Complete Issue 9, 1994 Feb 1994

Complete Issue 9, 1994

Humanistic Mathematics Network Journal

No abstract provided.


Using Tickets To Enforce The Serializability Of Multidatabase Transactions, Dimitrios Georgakopoulos, Marek Rusinkiewicz, Amit P. Sheth Feb 1994

Using Tickets To Enforce The Serializability Of Multidatabase Transactions, Dimitrios Georgakopoulos, Marek Rusinkiewicz, Amit P. Sheth

Kno.e.sis Publications

To enforce global serializability in a multidatabase environment the multidatabase transaction manager must take into account the indirect (transitive) conflicts between multidatabase transactions caused by local transactions. Such conflicts are difficult to resolve because the behavior or even the existence of local transactions is not known to the multidatabase system. To overcome these difficulties, we propose to incorporate additional data manipulation operations in the subtransactions of each multidatabase transaction. We show that if these operations create direct conflicts between subtransactions at each participating local database system, indirect conflicts can be resolved even if the multidatabase system is not aware of …


Impacts Of Projected Climate Change On Urban Water Use, United States Department Of The Interior, Bureau Of Reclamation Feb 1994

Impacts Of Projected Climate Change On Urban Water Use, United States Department Of The Interior, Bureau Of Reclamation

Water

Urban water use, particularly outdoor use, responds to changes in temperature, precipitation, and other climatic parameters. This study significantly improved the capacity of an existing regional water demand model to estimate the response of both residential and commercial-industrial water demand to changes in climatic parameters. The resulting functional relationships derived from historic time-series climatic and water use data were applied to global climate scenarios for the four Wasatch Front counties of Utah.


The Language Of Mathematics: A Quantitative Course For A General Audience, Stephanie F. Singer Feb 1994

The Language Of Mathematics: A Quantitative Course For A General Audience, Stephanie F. Singer

Humanistic Mathematics Network Journal

No abstract provided.


Writing Mathematics, E. G. Bernard Feb 1994

Writing Mathematics, E. G. Bernard

Humanistic Mathematics Network Journal

No abstract provided.


Drought Monitoring And Advisory Services In South Africa, M. V. Laing Feb 1994

Drought Monitoring And Advisory Services In South Africa, M. V. Laing

Drought Network News (1994–2001)

The normal total rainfall for the summer rainfall areas in South Africa is 664 mm. Since 1963, the country has recorded 16 seasons below normal and 14 above normal. Since the 1982–83 season, 7 seasons have been below normal and 4 have been above normal. Of these last 11 years, two rainy seasons recorded less than 75% of normal rainfall, which is a coarse estimation of severe drought. These seasons were 1982–83, when an average total of only 408 mm was measured, and 1992–93, when the average total was 484 mm. Although 1991–92 has been called the worst drought this …


Water Current, Volume 26, No. 1, February 1994 Feb 1994

Water Current, Volume 26, No. 1, February 1994

Water Current Newsletter

UWIN Offers Forum for Water Information
Sixth Annual Festival Set for March
Register Now for Conference
From the Director
High Plains Groundwater as a Sustainable Resource
Nitrogen Conference Proceedings Available
Tropical Water Center Set Up
Brochure Describes Water Laboratory
Water Focus of Interest
High School Primer Out
National Fellowships Available in Water Sciences
Valmont Offers Grants
Symphony to Add New Note to Children's Groundwater Festival
National Forum Participants to Visit Festival
Water, Drought Management Focus of Western Conference


Cooperating Brokers To Support Cooperative Work, Vinod Anupam, Chandrajit Bajaj, Peinan Zhang Feb 1994

Cooperating Brokers To Support Cooperative Work, Vinod Anupam, Chandrajit Bajaj, Peinan Zhang

Department of Computer Science Technical Reports

No abstract provided.


Experiences With Tripwire: Using Integrity Checkers For Intrusion Detection, Gene H. Kim, Eugene H. Spafford Feb 1994

Experiences With Tripwire: Using Integrity Checkers For Intrusion Detection, Gene H. Kim, Eugene H. Spafford

Department of Computer Science Technical Reports

No abstract provided.