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Biological Activity And Conformational Analysis Of Nikkomycins And Their Analogs, Eduardo Krainer Jan 1990

Biological Activity And Conformational Analysis Of Nikkomycins And Their Analogs, Eduardo Krainer

Dissertations, Theses, and Capstone Projects

Nikkomycins and polyoxins are peptidyl nucleoside antibiotics produced by Streptomyces species. They are potent inhibitors of chitin synthetases from pathogenic fungi, and polyoxins have been used in Japan for many years as agricultural fungicides and for insect control. Since chitin synthetase is not found in mammals and both families of antibiotics are not toxic, these inhibitors are potentially attractive for clinical use. Unfortunately these compounds seem to have only a fungistatic action, and they are not used clinically at present.

A procedure for efficiently obtaining nikkomycins X and Z of very high purity from crude antibiotic is described. These nikkomycins …


The Hydrogeologic Effects Of Fly Ash Utilization In Concrete At Coal Creek Station, Underwood, North Dakota, Terry R. Johnson Jan 1990

The Hydrogeologic Effects Of Fly Ash Utilization In Concrete At Coal Creek Station, Underwood, North Dakota, Terry R. Johnson

Theses and Dissertations

Coal Creek Station is a two-unit 1100 megawatt electrical power plant located in southern McLean county, North Dakota. Annually, 5 million tons (4.5 million metric tons) of lignite are burned at the plant producing 550,000 tons (500,000 metric tons) of fly ash. Approximately 80,000 tons (72,624 metric tons) of ash are sold as a cement replacement, while the remainder is disposed of in lined evaporation ponds. The present study investigates the environmental consequences of ash utilization as an alternative to disposal, The Electric Power Research Institute (EPRI) provided funding for this investigation which involves the installation of 5,288 cu yds …


Measurement Of Magnetic Fluctuations By O-X Mode Conversion, L. L. Vahala, G. Vahala, N. Bretz Jan 1990

Measurement Of Magnetic Fluctuations By O-X Mode Conversion, L. L. Vahala, G. Vahala, N. Bretz

Electrical & Computer Engineering Faculty Publications

The possibility of measuring magnetic fluctuations in a fusion plasma is considered by examining the O→X mode conversion. Under certain conditions and with good angular resolution, this mode conversion can be attributed to the presence of magnetic fluctuations even though the level of these fluctuations is much lower than that of density fluctuations. Some nonideal effects such as mode polarization mismatch at the plasma edge are also discussed.


Application Of The Results Of Carbon Pellet Modeling To The Problem Of Plasma Penetration, L. L. Vahala, A. G. El Cashlan, G. A. Gerdin, P. B. Parks Jan 1990

Application Of The Results Of Carbon Pellet Modeling To The Problem Of Plasma Penetration, L. L. Vahala, A. G. El Cashlan, G. A. Gerdin, P. B. Parks

Electrical & Computer Engineering Faculty Publications

The assumptions of the evaporation model for low-Z pellets interacting with magnetic fusion plasmas developed by Parks are tested. These assumptions are that the vapor density profile in the region adjacent to the pellet surface falls off with radial distance as r-α , where 5 <α<6, and that the ionization time for the transition between charge states זf (i.e., for r < ~3 sonic radii). The first assumption is tested by solving a two-parameter eigenvalue problem for the evaporation cloud in the region interior to the sonic radius; the results are found to be consistent with the low-Z evaporation model. The second assumption, that זzi «זf, is tested at the sonic radius using the results from atomic physics and the low-Z evaporation model. It is found that indeed זzi «זf for plasmas with parameters close to thermonuclear conditions (e.g. CIT), but not for those of smaller Tokamaks such as …


Application Of Microwave Technology To Effect On-Site Regeneration Of Gac, K.C. Mahesh Dec 1989

Application Of Microwave Technology To Effect On-Site Regeneration Of Gac, K.C. Mahesh

Theses

The off-site regeneration of granulated activated charcoal(GAC), spent as a result of stripping of organics from aqueous waste streams, represents a burdensome cost both because of the actual cost of regeneration and legal liability associated with shipping a hazardous waste off-site: that liability is reflected in huge potential costs associated with mishaps enroute for the self-insured or high premiums paid to the casualty insurance companies for those generators that are insured by third parties. Thus there is a need for the development of a process to effect on-site regeneration of spent GAC cost-effectively.

This thesis mainly focuses on the technical …


Aqueous Absorption Of Nox Induced By Sodium Chlorite Oxidation, Chen-Lu Yang Dec 1989

Aqueous Absorption Of Nox Induced By Sodium Chlorite Oxidation, Chen-Lu Yang

Theses

Aqueous scrubbing in alkaline media for the removal of nitrogen oxides (NOx) from flue gases using NaClO2 as an oxidant is being investigated in the Chemical Engineering Department of New Jersey Institute of Technology. This thesis presents the findings of an experimental program that was conducted to estimate the capability of NaClO2 aqueous solution to oxidize insoluble NO to soluble NO2 in order to increase its solubility and thus prevent NOx emission from entering the atmosphere from flue gases emitted by municipal incinerators or power plants.

The key findings of this program are:

* …


Development Of An Expert System To Convert Knowledge-Based Geological Engineering Systems Into Fortran, Jill J. Cress, Ralph W. Wilkerson Dec 1989

Development Of An Expert System To Convert Knowledge-Based Geological Engineering Systems Into Fortran, Jill J. Cress, Ralph W. Wilkerson

Computer Science Technical Reports

A knowledge-based geographic information system (KBGIS) for geological engineering map (GEM) production was developed in GoldWorks, an expert system development shell. GoldWorks allows the geological engineer to develop a rule base for a GEM application. Implementation of the resultant rule base produced a valid GEM, but took too much time. This proved that knowledge-based GEM production was possible but in GoldWorks implementation failed as a practical production system. To solve this problem, a Conversion Expert System was developed which accepted, as input, a KBGIS and produced, as output, the equivalent Fortran code. This allowed the engineer to utilize GoldWorks for …


Hassler Whitney 1907-1989: Some Recollections, 1979·1989, Anneli Lax Dec 1989

Hassler Whitney 1907-1989: Some Recollections, 1979·1989, Anneli Lax

Humanistic Mathematics Network Journal

No abstract provided.


Lessons From Cognitive Theory For Teaching Mathematical Modeling To Freshmen, Richard H. Elderkin Dec 1989

Lessons From Cognitive Theory For Teaching Mathematical Modeling To Freshmen, Richard H. Elderkin

Humanistic Mathematics Network Journal

No abstract provided.


An Empowering, Participatory Research Model For Humanistic Mathematics Pedagogy, Arthur B. Powell, Dawud A. Jeffries, Aleshia E. Selby Dec 1989

An Empowering, Participatory Research Model For Humanistic Mathematics Pedagogy, Arthur B. Powell, Dawud A. Jeffries, Aleshia E. Selby

Humanistic Mathematics Network Journal

No abstract provided.


Education Is For The Students' Future, Hassler Whitney Dec 1989

Education Is For The Students' Future, Hassler Whitney

Humanistic Mathematics Network Journal

No abstract provided.


Pdp/Academic Excellence Workshops In Mathematics, M. Catharine Hudspeth Dec 1989

Pdp/Academic Excellence Workshops In Mathematics, M. Catharine Hudspeth

Humanistic Mathematics Network Journal

No abstract provided.


Abstracts Of All Papers Presented At The Humanistic Mathematics Sessions In Phoenix 1989 Dec 1989

Abstracts Of All Papers Presented At The Humanistic Mathematics Sessions In Phoenix 1989

Humanistic Mathematics Network Journal

No abstract provided.


Adiabatic Population Transfer In A Three-Level System Driven By Delayed Laser Pulses, J. R. Kuklinski, U. Gaubatz, Foek T. Hioe, K Bergmann Dec 1989

Adiabatic Population Transfer In A Three-Level System Driven By Delayed Laser Pulses, J. R. Kuklinski, U. Gaubatz, Foek T. Hioe, K Bergmann

Physics Faculty/Staff Publications

We give a simple analytic solution that describes a novel method for population transfer in a three-level system driven by delayed pulses and which accounts for recent experimental results. This solution describes a procedure that is counter intuitive, and yet it is shown to be, in fact, one of the simplest solutions for multilevel systems arising from the adiabatic theorem. Its possible application to many-level systems is suggested.


Attribute Relationships: An Impediment In Automating Schema Integration, Amit P. Sheth, Sunit K. Gala Dec 1989

Attribute Relationships: An Impediment In Automating Schema Integration, Amit P. Sheth, Sunit K. Gala

Kno.e.sis Publications

Success in schema integration depends on understanding the semantics of schema components (e.g., entity sets, relationship sets, attributes), and the ability to capture and reason about these semantics. An important objective of our work on schema integration is to automate the reasoning as much as possible, and when not possible, depend on the human input and guidance. A key results of comparing the semantics associated with schema objects is that of determining attribute relationship. Once attribute relationships are determined, the task of object class(e.g., entity sets and relationship sets) integration becomes simpler and can e automated to a great extent. …


The Probe, Issue 98 - December 1989 Dec 1989

The Probe, Issue 98 - December 1989

The Probe: Newsletter of the National Animal Damage Control Association

THE PROBE National Animal Damage Control Association
DECEMBER 1989
Vote
NADCA Elections
NADCA Annual Meeting
Letters to Ye Ed
APHIS Activity Report
Animal Rights


Calculation Of Electron Scattering For 4He In A Continuum Shell Model, Ming Yu Dec 1989

Calculation Of Electron Scattering For 4He In A Continuum Shell Model, Ming Yu

Masters Theses

Calculations for the electroexcitation of the 4He, O+ state have been performed within the context of recoil corrected continuum shell model. Approximations previously employed for inelastic scattering with the recoil corrected continuum shell model are eliminated in the work. The O+ state exhausts only 10% of the energy weighted sum rule and previous shell model calculations for the excitation of this state produce about ten times too much strength. This difficulty is alleviated by the use translationally invariant wave functions and the application of continuum boundary conditions for this particle unbound state. The structure of the O+ state is …


The Role Of Small-Impact-Parameter Electron-Loss Processes On Ion Temperatures Measured By Active-Beam Plasma Diagnostics, A. J.H. Donné, F. J. De Heer, Ronald E. Olson Dec 1989

The Role Of Small-Impact-Parameter Electron-Loss Processes On Ion Temperatures Measured By Active-Beam Plasma Diagnostics, A. J.H. Donné, F. J. De Heer, Ronald E. Olson

Physics Faculty Research & Creative Works

The shape of the energy distribution of scattered particles in an active beam scattering experiment can be influenced considerably by the presence of highly charged impurity ions in the plasma. In this work it is shown theoretically that multiply charged impurities have only a small effect on the scattering distribution at low energies (/amu) and at high energies (>75 keV/amu). The effect of the impurities is the most pronounced for energies close to 50 keV/amu. The results of the calculations are in good agreement with experimental results at various energies. Extrapolation to higher beam energies leads to the conclusion …


Computer Vandalism And The Law, Eugene H. Spafford Nov 1989

Computer Vandalism And The Law, Eugene H. Spafford

Department of Computer Science Technical Reports

No abstract provided.


A Computer Virus Primer, Eugene H. Spafford, Kathleen A. Heaphy, David J. Ferbrache Nov 1989

A Computer Virus Primer, Eugene H. Spafford, Kathleen A. Heaphy, David J. Ferbrache

Department of Computer Science Technical Reports

No abstract provided.


A Workload Partitioning Strategy For Pdes By A Generalized Neural Network, Elias N. Houstis, S. K. Kortesis, H. Byun Nov 1989

A Workload Partitioning Strategy For Pdes By A Generalized Neural Network, Elias N. Houstis, S. K. Kortesis, H. Byun

Department of Computer Science Technical Reports

No abstract provided.


The Internet Worm Incident, Eugene H. Spafford Nov 1989

The Internet Worm Incident, Eugene H. Spafford

Department of Computer Science Technical Reports

No abstract provided.


Experimental Facility For Kernel Extensions To Support Distributed Database Systems, Bharat Bhargava, Enrique Mafla, John Riedl Nov 1989

Experimental Facility For Kernel Extensions To Support Distributed Database Systems, Bharat Bhargava, Enrique Mafla, John Riedl

Department of Computer Science Technical Reports

No abstract provided.


Efficient Geometric Algorithms In The Erew-Pram, Danny Z. Chen Nov 1989

Efficient Geometric Algorithms In The Erew-Pram, Danny Z. Chen

Department of Computer Science Technical Reports

No abstract provided.


An Extended Transaction Model For Multidatabase Systems, Yungho Leu, Ahmed K. Elmagarmid, Marek Rusinkiewicz Nov 1989

An Extended Transaction Model For Multidatabase Systems, Yungho Leu, Ahmed K. Elmagarmid, Marek Rusinkiewicz

Department of Computer Science Technical Reports

No abstract provided.


Ua66/3/2 Computer Science Alumni Newsletter, Vol. 5, Wku Computer Science Nov 1989

Ua66/3/2 Computer Science Alumni Newsletter, Vol. 5, Wku Computer Science

WKU Administration Documents

Newsletter created by WKU Computer Science for the alumni of the program.


The Probe, Issue 97 - November 1989 Nov 1989

The Probe, Issue 97 - November 1989

The Probe: Newsletter of the National Animal Damage Control Association

THE PROBE National Animal Damage Control Association
NOVEMBER 1989
APHIS Activity Report
Letters to Ye Ed
Animal Rights
The Humane Society
Personnel
Freeze Dirt
Coyotes are Dangerous


Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, November 1989, College Of Engineering And Computer Science, Wright State University Nov 1989

Wright State University College Of Engineering And Computer Science Bits And Pcs Newsletter, November 1989, College Of Engineering And Computer Science, Wright State University

BITs and PCs Newsletter

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


Prophet Inequalities For Parallel Processes, Theodore P. Hill, D. P. Kennedy Nov 1989

Prophet Inequalities For Parallel Processes, Theodore P. Hill, D. P. Kennedy

Research Scholars in Residence

Generalizations of prophet inequalities for single sequences are obtained for optimal stopping of several parallel sequences of independent random variables. For example, if {Xi, j, 1 ≤ i ≤ n, 1 ≤ j < ∞} are independent non-negative random variables, then E(sup Xi,j) ≤ (n + 1) max sup {E(Xi,t): t is a stop rule for Xi,1, Xi,2, ...} and this bound is best possible. Applications are made to comparisons of the optimal expected returns of various alternative methods of stopping of parallel processes.


On The Height Of Digital Trees And Related Problems, Wojciech Szpankowski Nov 1989

On The Height Of Digital Trees And Related Problems, Wojciech Szpankowski

Department of Computer Science Technical Reports

No abstract provided.