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1995

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Articles 1981 - 2010 of 2193

Full-Text Articles in Physical Sciences and Mathematics

Shape Reconstruction From Shading Using Linear Approximation, Ping Sing Tsai Jan 1995

Shape Reconstruction From Shading Using Linear Approximation, Ping Sing Tsai

Retrospective Theses and Dissertations

Shape from shading (SFS) deals with the recovery of 3D shape from a single monocular image. This problem was formally introduced by Horn in the early 1970s. Since then it has received considerable attention, and several efforts have been made to improve the shape recovery. In this thesis, we present a fast SFS algorithm, which is a purely local method and is highly parallelizable. In our approach, we first use the discrete approximations for surface gradients, p and q, using finite differences, then linearize the reflectance function in depth, Z ( x , y), instead of p and q. This …


Analysis And Extension Of Model-Based Software Executives, Keith E. Lewis Jan 1995

Analysis And Extension Of Model-Based Software Executives, Keith E. Lewis

Theses and Dissertations

This research developed a comprehensive description of the simulation environment of Architect, a domain-oriented application composition system being developed at the Air Force Institute of Technology to explore new software engineering technologies. The description combines information from several previous research efforts and Architect's source code into a single, comprehensive document. A critical evaluation of the simulation environment was also performed, identifying improvements and modifications that enhance Architecture's application execution capabilities by reducing complexity and execution time. The analysis was then taken one step further and presented extensions to the current simulation environment. The extensions included investigating the feasibility of mixed-mode …


Cis-6-Methoxycarbonyl-2,10-Dioxa-1-Phosphabicyclo[4.4.0]Decane 1-Oxide, Thomas M. Lane, Oscar P Rodriguez, Anthony Gerard Sommese, Sheldon E. Cremer, Dennis W. Bennett Jan 1995

Cis-6-Methoxycarbonyl-2,10-Dioxa-1-Phosphabicyclo[4.4.0]Decane 1-Oxide, Thomas M. Lane, Oscar P Rodriguez, Anthony Gerard Sommese, Sheldon E. Cremer, Dennis W. Bennett

Chemistry Faculty Research and Publications

The crystal structure of the title compound, C9H1505P, is described. The molecule consists of two cis-fused six-membered rings, both in the chair conformation..


Visage: Improving The Ballistic Vulnerability Modeling And Analysis Process, Brett F. Grimes Jan 1995

Visage: Improving The Ballistic Vulnerability Modeling And Analysis Process, Brett F. Grimes

Theses and Dissertations

The purpose of this thesis was to improve the process of modeling and analyzing ballistic vulnerability data. This was accomplished by addressing two of the more urgent needs of vulnerability analysts; the ability to display fault tree data and to edit target descriptions. A vulnerability data visualization program called VISAGE was modified to meet these needs. VISAGE was originally created to preview static shotline plots and subsequently grew into a full-featured visualization package for vulnerability target descriptions and analyses data. The next logical step in the programs evolution was to include the needed editing and fault tree display capabilities. The …


Osse Observations In Blazars, K. Mcnaron-Brown, W. N. Johnson, G. V. Jung, R. L. Kinzer, J. D. Kurfess, M. S. Strickman, C. D. Dermer, D. A. Grabelsky, W. R. Purcell, M. P. Ulmer, Menas Kafatos, P. A. Becker, R. Staubert, M. Maisack Jan 1995

Osse Observations In Blazars, K. Mcnaron-Brown, W. N. Johnson, G. V. Jung, R. L. Kinzer, J. D. Kurfess, M. S. Strickman, C. D. Dermer, D. A. Grabelsky, W. R. Purcell, M. P. Ulmer, Menas Kafatos, P. A. Becker, R. Staubert, M. Maisack

Mathematics, Physics, and Computer Science Faculty Articles and Research

Results are reported on observations obtained with the Oriented Scintillation Spectrometer Experiment (OSSE) instrument on the Compton Gamma Ray Observatory (CGRO) of 17 active galactic nuclei (AGNs) known to exhibit blazar properties at other wavelengths. These observations span the period from 1991 June through 1994 May. Of the 33 high-confidence EGRET detections of blazars during CGRO observing phases 1 and 2 (1991 May 16-1993 September 7), OSSE has observed eight and detected five, namely 3C 273, 3C 279, PKS 0528+134, CTA 102, and 3C 454.3. Additionally, OSSE has detected the BL Lac sources H1517+65.6 and PKS 2155-304, which were not …


Mississippi River Flood Waters That Reached The Gulf Stream, Peter B. Ortner, Thomas N. Lee, Peter J. Milne, Rod G. Zika, M. Elizabeth Clarke, Guillermo P. Podesta, Peter K. Swart, Patricia A. Tester, Larry P. Atkinson, Walter R. Johnson Jan 1995

Mississippi River Flood Waters That Reached The Gulf Stream, Peter B. Ortner, Thomas N. Lee, Peter J. Milne, Rod G. Zika, M. Elizabeth Clarke, Guillermo P. Podesta, Peter K. Swart, Patricia A. Tester, Larry P. Atkinson, Walter R. Johnson

CCPO Publications

Distributions of physical, biological, and chemical parameters in Florida Keys coastal waters seaward of the reef track were surveyed on September 9 to 13, 1993, as part of a coordinated multidisciplinary study of surface transport processes. A band of low-salinity water was observed along the shoreward side of the Florida Current over the downstream extent of the survey from Miami to Key West. Biological and chemical indicators within the band, together with its large volume, satellite imagery, and a surface drifter trajectory suggested the recent Mississippi River flood as the source.


Rule Extraction: From Neural Architecture To Symbolic Representation, Gail A. Carpenter, Ah-Hwee Tan Jan 1995

Rule Extraction: From Neural Architecture To Symbolic Representation, Gail A. Carpenter, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

This paper shows how knowledge, in the form of fuzzy rules, can be derived from a supervised learning neural network called fuzzy ARTMAP. Rule extraction proceeds in two stages: pruning, which simplifies the network structure by removing excessive recognition categories and weights; and quantization of continuous learned weights, which allows the final system state to be translated into a usable set of descriptive rules. Three benchmark studies illustrate the rule extraction methods: (1) Pima Indian diabetes diagnosis, (2) mushroom classification and (3) DNA promoter recognition. Fuzzy ARTMAP and ART-EMAP are compared with the ADAP algorithm, the k nearest neighbor system, …


Adaptive Resonance Associative Map, Ah-Hwee Tan Jan 1995

Adaptive Resonance Associative Map, Ah-Hwee Tan

Research Collection School Of Computing and Information Systems

This article introduces a neural architecture termed Adaptive Resonance Associative Map (ARAM) that extends unsupervised Adaptive Resonance Theory (ART) systems for rapid, yet stable, heteroassociative learning. ARAM can be visualized as two overlapping ART networks sharing a single category field. Although ARAM is simpler in architecture than another class of supervised ART models known as ARTMAP, it produces classification performance equivalent to that of ARTMAP. As ARAM network structure and operations are symmetrical, associative recall can be performed in both directions. With maximal vigilance settings, ARAM encodes pattern pairs explicitly as cognitive chunks and thus guarantees perfect storage and recall …


Ua56/1 Fact Book, Wku Institutional Research Jan 1995

Ua56/1 Fact Book, Wku Institutional Research

WKU Archives Records

Statistical and demographic profile of WKU.


Object Interactions As First Class Objects: From Design To Implementation, Mahesh Dodani, Benjamin Kok Siew Gan, Lizette Velazquez Jan 1995

Object Interactions As First Class Objects: From Design To Implementation, Mahesh Dodani, Benjamin Kok Siew Gan, Lizette Velazquez

Research Collection School Of Computing and Information Systems

Collaborations between objects make up the dynamic behavior of OO software. These collaborations among objects require careful design and implementation. Treating the interactions as responsibilities that are integrated in the participating objects, results in tight coupling between objects. Tight coupling increases complexity and reduces reusability. Object interactions need to be first class objects from design to implementation. Our research provides a unified approach to model and implement these interactions as first class objects. During analysis and design, they are modeled using DynaSpecs. During implementation, they are coded with a new language construct called Compositions. DynaSpecs and Compositions provide a consistent …


Scanning-Tunneling-Microscopy Study Of Pb On Si(111), D. Tang, H. E. Elsayed-Ali, J. Wendelken, J. Xu Jan 1995

Scanning-Tunneling-Microscopy Study Of Pb On Si(111), D. Tang, H. E. Elsayed-Ali, J. Wendelken, J. Xu

Electrical & Computer Engineering Faculty Publications

Scanning-tunneling microscopy has been used to study temperature and coverage dependence of the structure of lead on the Si(111)-7×7 surface. For low Pb coverage, the Pb atoms favored the faulted sites. The ratio between the number of Pb atoms on faulted to unfaulted sites increased after sample annealing. An energy difference of 0.05 eV associated with a Pb atom on these two sites is estimated. The mobility of Pb atoms on Si(111) was observed at a temperature as low as 260°C for a coverage of 0.1 and 1 ML. © 1995 The American Physical Society.


Feasible Offset And Optimal Offset For General Single-Layer Channel Routing, Ronald I. Greenberg, Jau-Der Shih Jan 1995

Feasible Offset And Optimal Offset For General Single-Layer Channel Routing, Ronald I. Greenberg, Jau-Der Shih

Computer Science: Faculty Publications and Other Works

This paper provides an efficient method to find all feasible offsets for a given separation in a very large-scale integration (VLSI) channel-routing problem in one layer. The previous literature considers this task only for problems with no single-sided nets. When single-sided nets are included, the worst-case solution time increases from $\Theta ( n )$ to $\Omega ( n^2 )$, where n is the number of nets. But if the number of columns c is $O( n )$, the problem can be solved in time $O( n^{1.5} \lg n )$, which improves upon a “naive” $O( cn )$ approach. As a …


Computer Modelling Of A Dynamical Water Molecule, Donald Greenspan Jan 1995

Computer Modelling Of A Dynamical Water Molecule, Donald Greenspan

Mathematics Technical Papers

A model of a ground state water molecule is formulated dynamically and studied by computer simulations. The enigmatic 104.5° bond angle is approximated by introducing the effects of neighboring molecules in a crystaline state. The numerical methodology used conserves the system energy at all times. Illustrative examples are described and discussed.


A New Method For Approximating Quantum Dynamical Phenomena Over Short (And Sometimes Long) Time Periods, Donald Greenspan Jan 1995

A New Method For Approximating Quantum Dynamical Phenomena Over Short (And Sometimes Long) Time Periods, Donald Greenspan

Mathematics Technical Papers

Approximate electron and proton motions are simulated for short time periods for using a special case of the quantum mechanical Ehrenfest equations. Attention is directed only to ground state. A numerical method is employed which conserves the ground state energy at all times. Large proton motions are found, with electron trajectories oscillating between the protons, but concentrating around them.


Ignition And Environmental Effects Of Wildfires As Related To Giant Impacts, Gregory S. Kufner Jan 1995

Ignition And Environmental Effects Of Wildfires As Related To Giant Impacts, Gregory S. Kufner

Honors Projects

Soot has been discovered by Wolbach et al. at the Cretaceous-Tertiary boundary in various geographic locations, supporting the theory that worldwide wildfires were ignited by the impact of a giant meteorite which caused the mass extinction 65 million years ago. This project examines a deep sea core sample from the North Central Pacific Ocean for evidence of soot. Soot discovery at this site, the only deep ocean site to be studied, supports the theory that soot distribution from the fires was worldwide. In another project, samples from the suevite breccia of the Kara Ust-Kara craters in Russia (unrelated to the …


Photochemistry Of The Nitrite Ion, Laura J. Wilson '95 Jan 1995

Photochemistry Of The Nitrite Ion, Laura J. Wilson '95

Honors Projects

Nitrogen containing compounds contribute to many environmental problems such as acid rain, air pollution, groundwater contamination, and smog formation. For example, when the atmosphere is heavily polluted with nitrites and aromatic hydrocarbons, nitrogen compounds can undergo photochemical reactions to produce harmful compounds that can adversely affect the environment. This project studied the photochemistry of the nitrite ion in aqueous basic solution. Both ·OH and NO· radicals are produced during photolysis, but the two radicals recombine in the presence of pure water causing no net reaction. Aromatic compounds present in the solution being photolyzed can act as scavengers reacting with either …


Slow Motion In One-Dimensional Cahn-Morral Systems, Christopher P. Grant Jan 1995

Slow Motion In One-Dimensional Cahn-Morral Systems, Christopher P. Grant

Faculty Publications

In this paper we study one-dimensional Cahn-Morral systems, which are the multicomponent analogues of the Cahn-Hilliard model for phase separation and coarsening in binary mixtures. In particular, we examine solutions that start with initial data close to the preferred phases except at finitely many transition points where the data has sharp transition layers, and we show that such solutions may evolve exponentially slowly; i.e., if ε is the interaction length then there exists a constant C such that in exp(C/ε) units of time the change in such a solution is o(1). This corresponds to extremely slow coarsening of a multicomponent …


Genesis Of The Di̇vri̇ği̇ Iron Ore Deposit, Si̇vas, Central Anatolia, Turkey-An Ore Microscopy Study, Taner Ünlü, Henrik Stendal, Emil Makovicky, İ. Sönmez Sayili Jan 1995

Genesis Of The Di̇vri̇ği̇ Iron Ore Deposit, Si̇vas, Central Anatolia, Turkey-An Ore Microscopy Study, Taner Ünlü, Henrik Stendal, Emil Makovicky, İ. Sönmez Sayili

Bulletin of the Mineral Research and Exploration

No abstract provided.


Electric Field Mapping System With Nanosecond Temporal Rosolution, F. E. Peterkin, R. Block, K. H. Schoenbach Jan 1995

Electric Field Mapping System With Nanosecond Temporal Rosolution, F. E. Peterkin, R. Block, K. H. Schoenbach

Bioelectrics Publications

The electric field dependence of the absorption coefficient in semi‐insulating GaAs at the absorption edge was measured in a high‐voltage pulsed experiment. Pulse duration was kept below 50 ns in order to avoid thermal effects. A GaAs laser diode was used as a probe light source with wavelength varied from 902 to 911 nm. For fields up to 40 kV/cm the absorption coefficient increased from 3 to 17 cm−1 at 902 nm, with smaller absolute increases evident at the longer wavelengths. Calculation from theory was consistent with this behavior. The spatial variation of the electric field was also recorded …


Dynamic Phenomena In Layer Superconducting Cuprate And Organic Metals, Juana Acrivos, Lei Chen, C. Burch Jan 1995

Dynamic Phenomena In Layer Superconducting Cuprate And Organic Metals, Juana Acrivos, Lei Chen, C. Burch

Faculty Publications, Chemistry

Dynamic electron spin resonance (ESR) and extended x-ray absorption edge fine structure (XAFS) measurements suggest that layered organic metals and cuprate superconductors behave similarly. The response to microwave radiation in a modulated external magnetic field indicates that: (i) triplet state, T * ESR is observed below Tc for both; (ii) the condensation of free spin doublet D to T* occurs above the transition temperature to superconductivity Tc (10 ± 1 K for the organic metal (BEDT-TTF)3Ta2F11 and 92 to 12 K for YBa2Cu3O7-δ and its rare earth derivatives); (iii) antiferomagnetic (AF) resonance is detected above Tc for the organic metal. …


The Trace Of An Abelian Group:An Application To Digraphs, J. M. Burns, Brendan Goldsmith Jan 1995

The Trace Of An Abelian Group:An Application To Digraphs, J. M. Burns, Brendan Goldsmith

Articles

The trace of a finite Abelian group is used to give a short proof of a result of Arlinghaus and Harary on the digraph number of such a group


Equilibrium And Kinetic Studies Of Isomerization Of (Oc)5m[Η1-Pph2ch2ch(Pph2)2] And (Oc)5m[Η1-Pph2ch(Pph2)Ch2pph2] (M=Cr, Mo, W), Weiying Lin Jan 1995

Equilibrium And Kinetic Studies Of Isomerization Of (Oc)5m[Η1-Pph2ch2ch(Pph2)2] And (Oc)5m[Η1-Pph2ch(Pph2)Ch2pph2] (M=Cr, Mo, W), Weiying Lin

Masters Theses

It has been found that (OC)5M[η1-PPh2CH2CH(PPh2)2] and (OC)5M[η1-PPh2CH(PPh2)CH2PPh2] (M=Cr, Mo, W) exist in equilibrium in solution. This linkage isomerization is the first experimental evidence for the exchange of terminal and coordinated phosphorus groups in pentacarbonyl complexes of group 6 metals.

(OC)5M[η1-PPh2CH2CH(PPh2)2] ⇌ (OC)5M[η1-PPh2CH(PPh2)CH2PPh2]

(M = Cr, Mo, W)

In this work, equilibrium …


Reproductive Success Of Grassland Birds At East-Central Illinois Airports, Eric L. Kershner Jan 1995

Reproductive Success Of Grassland Birds At East-Central Illinois Airports, Eric L. Kershner

Masters Theses

We determined the densities and reproductive success of birds on airport grasslands in east-central Illinois. Seven airports were sampled between 10 April and 15 August 1994 in Clark, Coles, Crawford, Douglas, Edgar, Macon and Richland counties. Nineteen species were detected on the airport grasslands and 147 nests were found representing six different species. Eastern meadowlarks (Sturnella magna) were the most abundant nesting species found; 105 out of the 147 nests (71%). Other nesting species included: grasshopper sparrow (Ammodramus savannarum), savannah sparrow (Passerculus sandwichensis), red-winged blackbird (Agelaius phoeniceus), song sparrow (Melospiza melodia) and horned lark (Eremophilia alpestris). Overall nest success was …


Neutron Diffraction Studies Of Erni₅₋ₓcoₓ (X=0.68, 1.68, 2.26) Alloys, Z. Zu, William B. Yelon, G. K. Marasinghe, William Joseph James Jan 1995

Neutron Diffraction Studies Of Erni₅₋ₓcoₓ (X=0.68, 1.68, 2.26) Alloys, Z. Zu, William B. Yelon, G. K. Marasinghe, William Joseph James

Physics Faculty Research & Creative Works

ErNi5-xCox alloys were prepared by RF induction melting and analyzed using neutron powder diffraction. Rietveld analysis neutron diffraction data indicates the unit cell volume increases with Co content while the a and c lattice parameters show different dependencies on the composition. the Co atoms show higher affinity for the 3g sites than for the 2c sites. the Co sublattice tends to couple antiferromagnetically to the Er sublattice. the easy magnetization direction is along the c axis.


Cs2ga2o(Bo3)2, Robert W. Smith Jan 1995

Cs2ga2o(Bo3)2, Robert W. Smith

Chemistry Faculty Publications

The structure of dicaesium digallium diorthoborate oxide constitutes a new type of oxide borate. It consists of a three-dimensional gallium-oxide-orthoborate lattice with Cs atoms occupying large cavities in the lattice. This lattice is made from pairs of Ga atoms connected through a shared O atom along the [001] direction; these Ga dimers are interconnected through shared O vertices to trigonal BO3 groups along the [010], [110] and [i10] directions, completing the tetrahedral coordination environment of each Ga atom.


The Synthesis And Characterization Of Novel 5,6-Disubstituted 1,10-Phenanthrolines, Liansheng Zeng Jan 1995

The Synthesis And Characterization Of Novel 5,6-Disubstituted 1,10-Phenanthrolines, Liansheng Zeng

Masters Theses

Two new ligands, 5-amino-6-nitro-1,10-phenanthroline (5-NH2-6-NO2-phen), produced by amination of 5-NO2-1,10-phenanthroline, and 5,6-diamino-1,10-phenanthroline (5,6-(NH2) 2-phen) ,produced by reduction of 5-NH2-6-NO2-phen, have been synthesized and characterized. The ligand 5-NH2-6-NO2-phen has been coordinated to a Ru(II) metal center to produce the Ru(II)-polypyridine complex [ (bpy) 2Ru (5-NH2-6-NO2-phen)] (PF6 ) 2 (bpy= 2, 2' -bipyridine) . This complex has been characterized by IR, UV-Vis, 1H-NMR, and cyclic voltammetry (CV) .


Isomerization And Chelation Studies Of Dangling Phosphine Complexes Of Group 6, Zhongjiang Jia Jan 1995

Isomerization And Chelation Studies Of Dangling Phosphine Complexes Of Group 6, Zhongjiang Jia

Masters Theses

Vinyl addition reactions, catalyzed by 2,2'-azobis(isobutyronitrile) (AIBN), have been used to prepare six pentacarbonyl complexes of group 6, each of which contains a dangling Ph2PCH2CH2P(p-tol)2 ligand.

Each of the six complexes undergoes slow isomerizationand chelation at 55 °C in perdeuterated toluene:

The reactions were monitored by 31P{1H} NMR spectroscopy. The isomerization reactions are reversible in solution, while the chelated products form irreversibly with the loss of carbon monoxide. The rate constants, K1 and K-1, have been determined for the three pairs of linkage isomers. Equilibrium …


Novel Compounds (Including Transition-Metal Complexes) Based On 1,10-Phenanthroline-5,6-Dione, Hui Zhou Jan 1995

Novel Compounds (Including Transition-Metal Complexes) Based On 1,10-Phenanthroline-5,6-Dione, Hui Zhou

Masters Theses

This thesis describes the synthesis of the transition metal complex [(bpy) 2OsII (pptd)] (PF6)2·2H2O, an analog of [(bpy) 2RuII (pptd)] (PF6)2·2H2O. Spectroscopic and electrochemical data on this complex are reported here. It was found that the electronic communication between the metal center and the pteridinedione portion of pptd did not appear to be enhanced in the Os(II) complex relative to its Ru(II) analog. The increased ability of Os(II) to undergo backbonding appeared to affect only the 1,10-phenanthroline portion of pptd.

A useful …


The Synthesis And Characterization Of [Ruii (Bpy) 2 (Biphen) ] (Pf6)2 And [ (Bpy) 2ruii (Biphen) Ruii (Bpy) 2] (Pf6)4, Mei-Yueh Chang Jan 1995

The Synthesis And Characterization Of [Ruii (Bpy) 2 (Biphen) ] (Pf6)2 And [ (Bpy) 2ruii (Biphen) Ruii (Bpy) 2] (Pf6)4, Mei-Yueh Chang

Masters Theses

A new bidentate polypyridine bridging ligand (biphen), produced by the condensation of 1,10-phenanthroline-5,6-dione with 5,6-diamino-phenanthroline has been synthesized and characterized. In addition the monometallic complex [(bpy)2RuII(biphen)](PF6)2 and the bimetallic complex [(bpy)2RuII(biphen)RuII(bpy)2](PF6)4 have been prepared. The complexes were characterized by elemental analysis, by 1H-NMR spectroscopy and by cyclic voltsmmetry(CV).

The results of these analyses seem to indicate that biphen acts like two independent units when attached to a - RuII(bpy)2 fragment. a bipyridine portion and a phenazine portion. Moreover, …


The Analysis And Isolation Of Diarrhetic Shellfish Poisoning Toxins, Seán S. Kelly Jan 1995

The Analysis And Isolation Of Diarrhetic Shellfish Poisoning Toxins, Seán S. Kelly

Theses

This research was initiated to examine the Diarrhetic Shellfish Poisoning (DSP) toxin profiles in mussels (Mytilus edulis) in south-west Ireland. Extensive sampling and testing of shellfish was conducted during the toxic periods of 1991 to 1994. This was the most comprehensive study ever undertaken of toxin profiles in shellfish from a single cultivation area.

A new toxin named dinophysistoxin-2 (DTX-2), which is an isomer of okadaic acid (OA), was the major toxin during prolonged DSP episodes. This toxicity in shellfish occuired soon after high cell counts of Dinophysis acuta were observed. As well as seasonal variability in toxin levels, substantial …