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Full-Text Articles in Physical Sciences and Mathematics

Pargal: A Package For Parallel Graph Algorithms, Winston Anand-Kumar Dec 1992

Pargal: A Package For Parallel Graph Algorithms, Winston Anand-Kumar

Masters Theses

In this thesis, we have considered three graph problems namely, spanning forest problem, connected component problem and minimum cost spanning forest problem. Standard methods to solve these problems using sequential algorithms by various authors are presented for each problem. Efficient parallel algorithms for these problems have also been presented by various authors; however, most of these solutions demands a need for large number of processors, which immediately increases the cost of the hardware and in most of the cases it seems not very practical.

We present efficient solutions for the three problems on a hypercube parallel computer using p processors. …


Geology Newsletter- 1992, Department Of Geology Dec 1992

Geology Newsletter- 1992, Department Of Geology

Geological and Environmental Sciences News

Vol.1, No. 17

  • Faculty News
  • Alumni/ Friends/ Former Faculty Notes
  • New Alumni
  • Awards and Scholarships
  • Geology Development and Scholarship Donations
  • Service Staff News
  • Grand Canyon Raft Adventure


A Critical Examination Of The Use Of Preliminary Tests In Two-Sample Tests Of Location, Kimberly Tucker Perry Dec 1992

A Critical Examination Of The Use Of Preliminary Tests In Two-Sample Tests Of Location, Kimberly Tucker Perry

Dissertations

The purpose of this dissertation was to explore the appropriateness of testing the equality of two means using either a t test, the Welch test, or the Mann-Whitney-Wilcoxon test for two independent samples based on the results of using two classes of preliminary tests. One class of preliminary tests determines whether the population variances differ, and the other class ascertains if the underlying distributions are symmetric or skewed. The F-ratio test and the Levene test (using the median) were compared as preliminary tests for variance homogeneity; and the DAgostino Sy and the Triples tests were also compared as preliminary tests …


Computational Neural Networks In Chemistry: Model Free Mapping Devices For Predicting Chemical Reactivity From Molecular Structure, David Wayne Elrod Dec 1992

Computational Neural Networks In Chemistry: Model Free Mapping Devices For Predicting Chemical Reactivity From Molecular Structure, David Wayne Elrod

Dissertations

Computational neural networks (CNNs) are a computational paradigm inspired by the brain’s massively parallel network of highly interconnected neurons. The power of computational neural networks derives not so much from their ability to model the brain as from their ability to learn by example and to map highly complex, nonlinear functions, without the need to explicitly specify the functional relationship. Two central questions about CNNs were investigated in the context of predicting chemical reactions: (1) the mapping properties of neural networks and (2) the representation of chemical information for use in CNNs.

Chemical reactivity is here considered an example of …


An Integrated Simulation Model Development Environment For Slam Ii Using Object-Oriented Paradigm, Rizvan Erol Dec 1992

An Integrated Simulation Model Development Environment For Slam Ii Using Object-Oriented Paradigm, Rizvan Erol

Masters Theses

An integrated simulation model development environment was implemented to assist the modeler by automating certain activities of simulation modeling. The system included interactive model definition, experimental design, automatic simulation program generation in SLAM II. Object-oriented paradigm at software development stage was extensively used to conceptualize the structure, and rules of the SLAM II language in order to generate efficient, and modular program code. The present system targeted modeling of various probabilistic inventory control system problems. The remarkable advantages of the system were rapid model development time, and achieving reliable program code without requiring any knowledge in SLAM II. Object-oriented programming …


Use Of Geology And Petrophysics In The Characterization Of St. Peter Sandstone Reservoirs, Rusli Bin Adam Dec 1992

Use Of Geology And Petrophysics In The Characterization Of St. Peter Sandstone Reservoirs, Rusli Bin Adam

Masters Theses

Core samples and petrophysical data from three reservoir intervals within the Middle Ordovician St. Peter Sandstone in the Michigan basin were utilized to assess the reservoir performance. Each reservoir interval coincides with major sedimentary facies which are in gradational contact with one another vertically and laterally throughout the basin. Reservoirs in the lower portions of the formation (reservoir type 1) are dominated by meso-intercrystalline porosity. This predominantly quartz cemented reservoir rock type is characterized by low porosity with high permeability, moderate pore apertures, and moderate irreducible water saturation. Reservoirs at the top of the formation (reservoir type 3) are dominated …


Multivariate Quadrature On Mimd Machines With Shared Or Distributed Memory, Ignatios E. Vakalis Dec 1992

Multivariate Quadrature On Mimd Machines With Shared Or Distributed Memory, Ignatios E. Vakalis

Dissertations

For a procedure as numerical integration, of high computational expense which is used extensively in large-scale computations, it is natural to aim at the design of algorithms which can be used on parallel computes. This work deeds with the design of efficient and portable parallel algorithms on MIMD (Multiple Instruction Multiple Data) architectures with shared memory, and on distributed memory systems.

A parallel global adaptive algorithm is presented for multivariate integration over simplex type regions. Process synchronization is achieved through the use of monitors. Macros were developed, for managing the task pool with a heap data structure. Layered over the …


A Study Of Ground-Water Quality In A Priority Agricultural And Livestock Watershed, Cass County, Michigan, Matthew Alan Stuk Dec 1992

A Study Of Ground-Water Quality In A Priority Agricultural And Livestock Watershed, Cass County, Michigan, Matthew Alan Stuk

Masters Theses

A study of ground-water contamination in a shallow, sandy, glacial drift aquifer was performed in a watershed dominated by swine feedlots and crop fields in Cass County, Michigan. Monitoring wells were installed and sampled to study the flow pattern, chemistry, and contamination of ground water.

Results of chemical analyses show contamination from fertilizers and other soil-applied chemicals as well as the infiltration of breakdown products from pig waste. Shallow wells in impacted areas show potassium and nitrate from the breakdown of fertilizers, calcium from field application of lime, and additional nitrate from pig waste. Elevated calcium, potassium, and nitrate concentrations …


An Efficient Over-The-Cell Routing Algorithm For High Performance Circuits, Sivakumar Natarajan Dec 1992

An Efficient Over-The-Cell Routing Algorithm For High Performance Circuits, Sivakumar Natarajan

Masters Theses

In this thesis, we present a three-layer and a two-layer over-the-cell (OTC) channel routing algorithm (WILMA3 and WILMA2 respectively) for high speed circuits. This router not only minimizes the channel height by using over-the-cell areas but also achieves the net’s timing requirements.

We have implemented our routers in C on SUN Sparc 1+ workstation and tested it on MCNC benchmarks Primary I and II. Experimental results show that WILMA3 can achieve results which are 72% better (on the average) than the conventional two layer channel router, 61% better than two layer over-the-cell router and 51% better than three layer greedy …


Eztex: A Graphical User Interface System For Latex, Ravi K. Kosaraju Dec 1992

Eztex: A Graphical User Interface System For Latex, Ravi K. Kosaraju

Masters Theses

No abstract provided.


Improved Global Routing Using ⋋-Geometry, Surendra Burman Dec 1992

Improved Global Routing Using ⋋-Geometry, Surendra Burman

Masters Theses

No abstract provided.


Synthesis Of Symmetric And "Mixed-Ligand" Homocyclopentadienyl Ruthenocenes, John Adjeiku Amanfu Dec 1992

Synthesis Of Symmetric And "Mixed-Ligand" Homocyclopentadienyl Ruthenocenes, John Adjeiku Amanfu

Masters Theses

No abstract provided.


A Computer Simulation Of The Rotary Vacuum Filter Brown Stock Washing System Using Distribution Sampling, Edison G. Yiu Dec 1992

A Computer Simulation Of The Rotary Vacuum Filter Brown Stock Washing System Using Distribution Sampling, Edison G. Yiu

Masters Theses

A probabilistic model was utilized to simulate the brown stock washing system's error due to process variability and measurement noise. Mass balances of the washing system were performed using distribution sampling. This model relies on a nonlinear relationship between displacement and dilution, which permitted the generation of displacement ratio based upon wash liquor ratio. Experimental trials were performed on a pilotscale rotary vacuum single-stage washer. Nonlinear first-order relationship appears to characterize a pilotscale washer adequately. Differences were observed between the means and standard deviations of the measured results compared to the simulation output. Future work is needed to identify the …


Construction Of A Lithium Vapor Oven For Electron Capture And Multiple Ionization Experiments, Oliver Woitke Aug 1992

Construction Of A Lithium Vapor Oven For Electron Capture And Multiple Ionization Experiments, Oliver Woitke

Masters Theses

A Li vapor oven, to be used as a source of Li target atoms in electron capture and multiple ionization experiments, was designed and installed in the beamline of the Van de Graaff accelerator at Western Michigan University. The oven was tested using two different projectile beams, protons and He+. The test results indicate that Li evaporated from the oven in the form of a cloud rather than as a jet spray. For He+ colliding with Li it was found that the projectile single-electron loss yield is about three orders of magnitude larger than the single-electron capture yield, as expected …


Charge Conservation In The Incommensurate-Commensurate Transition Of Charge Density Waves, Jörg Kastrup Aug 1992

Charge Conservation In The Incommensurate-Commensurate Transition Of Charge Density Waves, Jörg Kastrup

Masters Theses

W ith the complex continuation method, introduced by Gupta and Sutherland (1976), the grand partition function for the sine-Gordon model of charge density waves may be calculated without violation of charge conservation. Contrary to previous works by Okwamoto, Takayama and Shiba (1979) and Turkevich and Doniach (1982) the chemical potential becomes temperature dependent. By direct comparison of numerical results with those of the above mentioned authors it is shown that the incommensurate-commensurate transition does not occur in the previously predicted temperature range.


Localization Of Light In One Dimensional Randomly Disordered Dielectric Medium, K. Balaji Aug 1992

Localization Of Light In One Dimensional Randomly Disordered Dielectric Medium, K. Balaji

Masters Theses

The concept of localization of electrons in semiconductors has been known ever since the 1960's when P. W. Anderson and N. F. Mott made detail investigations on the transport properties of alloys. At the end of the last decade, however, physicist started looking for localization in other systems. Specifically, they looked at the localization of light and acoustic waves in disordered systems. Localization is a property which arises for all wavelike excitations in disordered media.

In this study we analyze the localization of light in one dimensional randomly disordered dielectric medium using computer simulation (numerical integration method) technique. The results …


A Study Of The Transfer Matrix Method For The Classical Statistical Mechanics Of One Dimensional Systems, Dietmar R.A. Johlen Aug 1992

A Study Of The Transfer Matrix Method For The Classical Statistical Mechanics Of One Dimensional Systems, Dietmar R.A. Johlen

Masters Theses

Two formalisms using the transfer matrix technique, the first one by Gupta and Sutherland (1976) and the second one by Guyer and Miller (1979), are investigated and a proof is given for their equivalence.

Furthermore, it is pointed out that previous studies neglected the difficulties that arise from nonhermitian pseudo Hamiltonian. This work proves that the same results are obtained by taking into account the nonhermiticity of the pseudo Hamiltonian.

Thus, the transfer integral technique is extended to nonhermitian pseudo Hamiltonians.


Sequential And Parallel Discrete Event Simulation On Computer Communication Networks, Tao Zhou Jun 1992

Sequential And Parallel Discrete Event Simulation On Computer Communication Networks, Tao Zhou

Masters Theses

This thesis presents the discrete event simulation technique on the network design, focusing on the methodology, modeling and implementation. The developed technique is suitable for the analysis of any store-and-forward computer communication networks with any level of complexity. The proposed generic simulation model can be used to test the architectures and protocols of existing networks and networks being designed. In implementation of the sequential discrete event simulation, an object-oriented programming strategy is applied to the network simulation using the C++ language. The parallel discrete event simulation is introduced to solve the problem of long time execution of the sequential simulation …


Maximal And Maximum Independent Sets In Graphs, Jiuqiang Liu Jun 1992

Maximal And Maximum Independent Sets In Graphs, Jiuqiang Liu

Dissertations

A maximal independent set of a graph G is an independent set which is not contained properly in any other independent set of G. An independent set is called maximum if it is of largest cardinality. Denote i(G) to be the number of maximal independent sets of G. These special sets and the parameter i(G) have interested many researchers leading to a number of properties and results. One of these is the determination of the maximum number of maximal independent sets among all graphs of order n, and the external graphs. In this investigation,we develop new properties for …


Prediction Of Paper Color: A Process Simulation Approach, Mayank Chaturvedi Jun 1992

Prediction Of Paper Color: A Process Simulation Approach, Mayank Chaturvedi

Masters Theses

A simulation model was developed for a dye mixing process and for the prediction of the optical properties of the paper. The model was integrated with the MAPPS (Modular Analysis of Pulp and Paper Systems) simulation software package. The model was validated using dyed handsheets made in a laboratory and dyed paper made on a pilot papermachine. Validation comprised of prediction of the optical properties of the handsheets and the machine-made paper which contained various combinations of three non-fluorescent dyes. Sheet reflectances were predicted at 20 nanometer intervals for discrete light wavelength range of 400 to 700 nanometers and verified …


Common Moment Sets Of Complementary Graphs, Hang Chen Jun 1992

Common Moment Sets Of Complementary Graphs, Hang Chen

Dissertations

Two sequences of nonnegative integers have the k^th common moment if they have equal sums of k^th powers. We intend to study common moment sets of the degree sequences of complementary graphs, and similarly, of the score sequences of complementary tournaments.

In Chapter I, we first study common moment sets of arbitrary sequences of nonnegative integers. Some basic concepts are introduced. The relations between characteristic functions and initial common moments are discovered. We extend Hua’s discussion of the Tarry-Escott problem. We conclude that any finite subset of nonnegative integers can be a common moment set of some sequences, and conversely, …


Synthesis Of Organometallic Polymers, Po-Chang Chiang Jun 1992

Synthesis Of Organometallic Polymers, Po-Chang Chiang

Masters Theses

By the middle of the nineteenth century, organic chemists found high molecular weight compounds as by-products of some of their experiments. These compounds were thought of as products of a failed reaction. It was not until sixty years ago that the first polymers were deliberately synthesized. Today polymers are used in almost every facet of life and they are becoming more important with each passing day.

This research project focused on synthesizing conducting organometallic polymers. By linking aromatic rings with transition metals, the resultant polymers should have good electrical conductivity because of the interaction of (a) the p electrons on …


Double Differential Cross Sections For State-Selective Electron Capture By Low-Energy Ar4+ And Ar5+ Ions From He And Ar, Serefettin Yaltkaya Jun 1992

Double Differential Cross Sections For State-Selective Electron Capture By Low-Energy Ar4+ And Ar5+ Ions From He And Ar, Serefettin Yaltkaya

Masters Theses

Doubly differential cross sections, in angle and energy, for state-selective single-electron capture from He and Ar by Ar4+ and Ar5+ ions have been studied experimentally at laboratory impact energies of 25q, 50q, and lOOq eV (q = 4 and 5, where q is the ion charge state) and at laboratory scattering angles between 0° and 5.5°, by means of translational energy spectroscopy. The translational energy-gain spectra show that only a few final states are selectively populated. Final-state transition probabilities were found to depend strongly on the charge state of the projectile ion and the ionization potential of the …


On Planar Routing Of Multi-Terminal Nets In Vlsi Physical Design, Jahangir A. Hashmi Apr 1992

On Planar Routing Of Multi-Terminal Nets In Vlsi Physical Design, Jahangir A. Hashmi

Masters Theses

In this thesis, we study two problems related to the physical design of VLSI circuits. One problem is related to the VLSI global routing and the other is related to the detailed routing in a bounded region.

We consider the routing of multiple multi-terminal nets on a single layer. We suggest a new approach for this problem. Our approach is based on simultaneously finding a forest of k non-intersecting spanning trees. We present an O(n^3) algorithm for finding two spanning trees corresponding to two nets on a single layer.

We also study the problem of finding a minimum Steiner tree …


Calcite Cementation Of Pleistocene Glacial Deposits In Southwest Michigan, Robert Lee Tolliver Apr 1992

Calcite Cementation Of Pleistocene Glacial Deposits In Southwest Michigan, Robert Lee Tolliver

Masters Theses

No abstract provided.


Algorithms For Incomplete Hypercubes, Venkata K. Prabhala Apr 1992

Algorithms For Incomplete Hypercubes, Venkata K. Prabhala

Masters Theses

Networked multiprocessing architectures for parallel com putation offer an alternative to high cost supercomputing. Recently hypercube has emerged as the most versatile architecture for parallel com putations. However, the number of nodes m in a hypercube is a power of 2, 2d, where d is the dimension of the hypercube. In practice, it m ay not be possible to have a complete hypercube because the cost of upgradation is proportional to the num ber of nodes. Incomplete and Composite hypercubes help remove the exponential node(and hence cost) constraint.

In this thesis we establish the equality of m-node …


Groundwater Studies Near The Dowagiac Landfill Area, Dowagiac, Michigan, Using Seismic Resistivity Methods, Saiful B. Baharom Apr 1992

Groundwater Studies Near The Dowagiac Landfill Area, Dowagiac, Michigan, Using Seismic Resistivity Methods, Saiful B. Baharom

Masters Theses

Groundwater contamination has occurred in the vicinity of the Dowagiac landfill, Dowagiac, Michigan. The groundwater has been degraded by the presence of organic hydrocarbons, trichloroethylene in particular. At least two aquifers are thought to be present in the area with the upper unconfined aquifer being contaminated while a lower confined aquifer remains uncontaminated. This lower aquifer is thought to be protected from above by a clay layer. A combined geophysical survey consisting of seismic refraction and electrical resistivity surveys was conducted to determine the continuity and thickness of this clay layer as well as the extent of the contamination. A …


A Progressive Disease Model For Doubly-Censred Bivariate Survival Data That Accommodates Covariate Information, Hilmi F. Yahya Apr 1992

A Progressive Disease Model For Doubly-Censred Bivariate Survival Data That Accommodates Covariate Information, Hilmi F. Yahya

Dissertations

A model for the natural history of a progressive disease is developed. The model has three disease states and can be expressed as the joint distribution of two survival random variables.

Covariate information is incorporated into the model using the proportional hazards model for the marginal distributions. The model will also accommodate data with observations which are censored on one or both of the survival random variables.

The likelihood function for censored data is exhibited for finding the maximum likelihood estimates of the parameters and their standard errors for testing the effects of the covariates. The method used to obtain …


Hydrogeologic Characterization Of A Multi-Aquifer System At Station 11 In Kalamazoo, Michigan, Linda G. Jones Apr 1992

Hydrogeologic Characterization Of A Multi-Aquifer System At Station 11 In Kalamazoo, Michigan, Linda G. Jones

Masters Theses

The purpose of this study was to determine the hydraulic connection between the upper and lower confined glacial drift aquifers. The results of this study are based primarily upon the geologic profiles, a comparison of the head differences within each aquifer, potentiometric surfaces and different lag times for precipitation to reach each aquifer.

Results of the aquifer test showed that the upper confining layer pinches out in the western part of the well field. This area also provided significant recharge to the well field during the aquifer test. Data collected during the aquifer test and the increases in water levels …


A Survey Of Computer Use In Occupational Therapy Fieldwork Sites, Martha E. Parks Apr 1992

A Survey Of Computer Use In Occupational Therapy Fieldwork Sites, Martha E. Parks

Masters Theses

Eighty-three Western Michigan University occupational therapy fieldwork sites were surveyed to determine: (a) extent of computer use, (b) diagnostic categories with which computers are used, (c) extent of computer knowledge of registered occupational therapists (OTRs), and (d) adequacy of computer knowledge of fieldwork students. Forty-seven (56.6%) of the 83 surveys were returned. OTRs at 36 (76.6%) of the 47 sites currently use computers. Word processing is the most common way in which these OTRs use computers. The most common clinical use of computers is perceptual/motor assessment and treatment, while the most common research use of computers is for report writing. …