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Masters Theses

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Separation Of Copper And Iron In Natural Waters By Solid-Phase Extraction, Charles Bui Dec 1993

Separation Of Copper And Iron In Natural Waters By Solid-Phase Extraction, Charles Bui

Masters Theses

A separation scheme has been developed by utilizing Solid-Phase Extraction cartridges in order to isolate and characterize the charge of metals and their complexes in natural waters. These species can be analyzed by Atomic Absorption Spectroscopy (AAS), Inductively Coupled Plasma (ICP), and Ultraviolet-Visible Spectrophotometry (UVVIS).

This separation scheme would permit the determination of the concentration of metals, as well as providing information about the forms in which the metals exist, e.g., charge of metallic complexes.

Synthetic metal complexes were prepared in the laboratory in order to study the separation scheme as well as trying to understand the binding stability of …


Thermodynamic Properties Of Mixtures Of Aqueous Solutions Of Hydrochloric Acid And Cadmium Chloride, Copper Chloride, Manganese Chloride, And Zinc Chloride, Samia A. Kosa Dec 1993

Thermodynamic Properties Of Mixtures Of Aqueous Solutions Of Hydrochloric Acid And Cadmium Chloride, Copper Chloride, Manganese Chloride, And Zinc Chloride, Samia A. Kosa

Masters Theses

The densities of mixtures of aqueous solutions of hydrochloric acid and cadmium chloride, copper chloride, manganese chloride, and zinc chloride have been measured at constant ionic strengths of 1.0 and 3.0 molal at 25 °C. In the case of HCl, CdCl2 , and ZnCl2 the literature data were refit using Pitzer' s apparent molal volume equation and the binary solution parameters were determined. Density data were used to determine the volume of mixing (∆Vm). Data from Torok and Berecs were combined with our data for the mixtures with CuCl2 and MnCl2. Pitzer's volume …


A Study Of Aquifer Sensitivity And Vulnerability In Kalamazoo County, Michigan Based On Hydrogeologic And Agricultural Factors, Steven Douglas Chidester Dec 1993

A Study Of Aquifer Sensitivity And Vulnerability In Kalamazoo County, Michigan Based On Hydrogeologic And Agricultural Factors, Steven Douglas Chidester

Masters Theses

Groundwater in Kalamazoo County, Michigan has been impacted by human activities. This study presents a statistical method for predicting aquifer sensitivity/vulnerability within a glacio-hydrogeologic system.

Computerized data including 3620 water well records with partial chemical analyses, soil surveys, land use maps, and hydrogeologic reports were used to quantify aquifer parameters, nitrate-N contaminant concentrations, soil factors, and agricultural practices. Statistical analyses included simple t-tests , correlation, ANOV A, and multiple regression analyses.

The results indicate that there are statistically significant relationships between nitrate-N concentrations and depth of well submergence, well depth, clay thickness, partial clay thickness, land use, and soil slope. …


Development Of A Systematic Approach To The Implementation Of A Computer Integrated Manufacturing (Cim) For Small To Medium Sized Companies, G. Steven Trimmer Dec 1993

Development Of A Systematic Approach To The Implementation Of A Computer Integrated Manufacturing (Cim) For Small To Medium Sized Companies, G. Steven Trimmer

Masters Theses

CIM technology is rapidly becoming an essential part of businesses of all types and sizes. The impact on the culture of the enterprise is possibly of even greater complexity. Most existing implementations have been done by large businesses large teams of specialized talent.

The unique scope of this work is to simplify the implementation of CIM for small companies. The basic research derived from the WMU/IBM CIM Management Center, a fully functioning CIM facility that provides hands on experience to students and regional businesses.

The cultural references concerning CIM are derived from reading and personal experiences with industry while setting …


Precipitation Dynamics In Kalamazoo, Sw Michigan: A Stable Isotope Perspective, Madhav V. Machavaram Aug 1993

Precipitation Dynamics In Kalamazoo, Sw Michigan: A Stable Isotope Perspective, Madhav V. Machavaram

Masters Theses

No abstract provided.


Correlates Of Job Satisfaction Among Private Sector Employees In Saudi Arabia, Abdullah Al-Helelah Aug 1993

Correlates Of Job Satisfaction Among Private Sector Employees In Saudi Arabia, Abdullah Al-Helelah

Masters Theses

The primary objectives of the present study were to explore the level of job satisfaction and commitment among private sector employees in Saudi Arabia, and to examine the relationship between job satisfaction and employees' commitment.

Seven alternative hypotheses were tested against seven null hypotheses. Chi-square (x^2) was the test statistic for all seven hypotheses. The critical value of chi-square was determined by the degrees of freedom (df) and an alpha level of.05. Three hypotheses were confirmed that related job satisfaction to employees' commitment, satisfaction with length of working hours, and satisfaction with opportunities for interaction with co-workers on the job. …


Optimizing Communication Routing In Parallel Computer Architectures, Nikolaos T. Liolios Aug 1993

Optimizing Communication Routing In Parallel Computer Architectures, Nikolaos T. Liolios

Masters Theses

This thesis is a research effort to improve on existing algorithms for processor placement and routing on hypercube and 2d-transputer parallel architectures that perform communications through message propagation. Given a set of processors N, randomly distributed on the parallel computer network, the problem is to find an optimal communication routing that minimizes the number of required links and intermediate processors. It was concluded that the spanning tree is the best starting heuristic for the routing problem. For hypercubes an algorithm was developed that outperforms all algorithms in the literature. For 2d-transputers the method of overlap maximization used in VLSI routing, …


Size Imperfections In One-Dimensional Periodic Optical Arrays, Yan Zhong Aug 1993

Size Imperfections In One-Dimensional Periodic Optical Arrays, Yan Zhong

Masters Theses

The concepts of band theory for electrons can also be employed to describe the behavior of electromagnetic waves propagating in periodic dielectric structures. These periodic structures can produce photonic band gaps in which the propagation of electromagnetic waves is strictly prohibited. The introduction of impurities in such system gives rise to donor and acceptor gap modes in electron system and to energy gap modes in photonic system.

In my thesis, the impurity modes in one-dimensional, periodic, dielectric system will be studied. These modes are introduced in the 1-d dielectric structure by altering the thickness of one slab in an otherwise …


A Study Of Automated Estimating Of Software Cost, Steven Shouli Wang Aug 1993

A Study Of Automated Estimating Of Software Cost, Steven Shouli Wang

Masters Theses

The objectives of this thesis are to survey software cost estimation methods and to discuss how the methods can be applied as conceptual knowledge in a software cost estimation expert database system. The various applications of expert database systems are discussed. Consequently, a new method to approach the software cost estimation has been proposed.

This proposed method is based upon a dozen years of analyzing software cost models which have been done by some dedicated scientists in universities, research organizations, and industry. A CASE tool called IASCE has been designed to assist the project manager to estimate a proposed project …


Choosing And Using Children's Literature: The Rationales And Instructional Designs Of Preservice Teachers, Nancy J. Gooden Jul 1993

Choosing And Using Children's Literature: The Rationales And Instructional Designs Of Preservice Teachers, Nancy J. Gooden

Masters Theses

This study examined the extent to which preservice teachers were aware of gender related issues in their selection and use of children's literature. The review of research provided background information on the subject of gender equity in children's literature and explored the effects of stereotyped attitudes on students' academic performance, self-esteem, and career choices. The application project used three instruments of study: a gender attitude survey, an analysis of preservice teachers' rationales for literature selection, and an examination of preservice teachers' instructional designs. The results of this study indicated that preservice teachers may benefit from additional exposure to gender issues …


Nonlinear Dynamic Finite Element Simulation Of Hydroelastic Mounts For Light Weight Vehicles, Talla Jayapal Reddy Jun 1993

Nonlinear Dynamic Finite Element Simulation Of Hydroelastic Mounts For Light Weight Vehicles, Talla Jayapal Reddy

Masters Theses

Modern light weight vehicles generate large noise levels, that may need bulky classical rubber mounts to suppress. Hydroelastic mounts can significantly reduce the vibration level of current production automobiles without weight penalty. However, the highly nonlinear behavior of hydroelastic mounts has not been established yet and its use is, therefore, limited to trial and error design methods.

This study discusses the implementation of nonlinear finite element simulation of hydroelastic mounts using the ANSYS finite element code. Fluid elements are limited to linear analysis and therefore are incompatible with the nonlinear hyperelastic elements. A method is proposed to simulate the fluid …


On Clock Routing Techniques For Vlsi Synchronous Systems, Wasim A. Khan Jun 1993

On Clock Routing Techniques For Vlsi Synchronous Systems, Wasim A. Khan

Masters Theses

The clock signal is vital in maintaining proper dataflow, and thus the total throughput, of a high performance synchronous system.

In this thesis, we develop a clock distribution scheme for high performance systems which maximizes the operating clock frequency. We develop an algorithm which routes a planar clock tree with zero skew, minimum source to sink pathlength, and minimal total wirelength. The algorithm also provides a smooth tradeoff between maximum source to sink pathlength and total wirelength while keeping the clock skew at zero.

In many microprocessor designs, multi-phase clocks are used for improved system design. Routing a multiple clock …


Investigation Of Electron Transfer From Carbonylmetallate Anions To Electron Acceptors, Joseph Kofi Agyin Jun 1993

Investigation Of Electron Transfer From Carbonylmetallate Anions To Electron Acceptors, Joseph Kofi Agyin

Masters Theses

This study investigated electron transfer potential of the carbonyl-metallate anions cyclopentadienylirondicarbonyl and methylcyclopentadienyliron-dicarbonyl anions to the electron acceptors 2,2-dinitropropane, 1,1-dinitrocyclohexane, $\alpha$,p-dinitrocumene, methyl cyclopentadienyl-mercury(II) chloride and iodide.

The findings from this study indicated that: (a) the expected products could not be obtained from reactions of the anions with the dinitro-substrates, and (b) the mercurials reacted with the anions but the expected products, (ferrocene and methylferrocene), was the minor product and an unexpected (methyl) cyclopentadienylirondicarbonylmercury(II)-chloride or iodide was the major product.


The Effects Of Composting Of Yard Wastes On The Ground-Water Quality: Wmu Farms Site, Kalamazoo, Michigan, Bryan Kirk Allen Jun 1993

The Effects Of Composting Of Yard Wastes On The Ground-Water Quality: Wmu Farms Site, Kalamazoo, Michigan, Bryan Kirk Allen

Masters Theses

In the rush to find alternatives to landfilling of yard waste, federal and state agencies have identified composting as the main solution. There is therefore a need to address the possible environmental problems which could be associated with such composting operations. Compost may contain nutrients, organic acids, pesticides, and metals which could leach through soils to the ground water posing a potential contamination problem.

At the WMU Farms Site, two sites have been used for the composting of leaves by the City of Kalamazoo. The physical and chemical hydrogeology of these sites were characterized.

The results suggest that the presence …


Enhanced Retroreflection Of Light From Rough Metal Surfaces, Sivakumar Natarajan Jun 1993

Enhanced Retroreflection Of Light From Rough Metal Surfaces, Sivakumar Natarajan

Masters Theses

The optical constants n and k measured by Johnson and Christy (1972) for the noble metals (gold, silver and copper) are used to analyze the relationship between the surface characteristics and the peak height and half-width of the backscattering peak which is observed in the angular distribution of the intensity of diffusely reflected light at a vacuum-metal interface in a direction antiparallel to the original incident beam. Surfaces with surface roughness of heights less than 200 A to 300 A will be considered and a recently developed perturbation treatment will be used in these studies.

The backscattering of light from …


Groundwater Chemistry Analysis Of The Saginaw Formation In Delhi Township, Michigan, Sam L. Kitchin Jun 1993

Groundwater Chemistry Analysis Of The Saginaw Formation In Delhi Township, Michigan, Sam L. Kitchin

Masters Theses

Groundwater chemistry and well data provided by the Ingham County (Michigan) Health Department were used to evaluate the distribution of inorganic chemical constituents in the groundwater flow system of the Saginaw Formation, in Delhi Township, Michigan. The data also were used to study the distribution of chemical constituents with respect to different rock types of the Saginaw Formation. The data were analyzed to examine if variations in the concentrations of the chemical constituents and the values of other chemical parameters relate to rock-water interactions, groundwater flow systems, or groundwater contamination.

The results indicate that patterns of increasing or decreasing concentrations …


Laboratory Studies Of Filter Pack Grain-Size Distributions And Hydrophobic Treatments To Enhance The Recovery Of Free-Phase Floating Hydrocarbons, Hugh Garret Heuvelhorst Jun 1993

Laboratory Studies Of Filter Pack Grain-Size Distributions And Hydrophobic Treatments To Enhance The Recovery Of Free-Phase Floating Hydrocarbons, Hugh Garret Heuvelhorst

Masters Theses

Experiments were conducted in laboratory sand tanks to evaluate filter pack design criteria in an effort to improve free-product hydrocarbon recovery from sand aquifers. Filter sands were prepared and installed in the test tanks to examine the relative efficiency of two different grain sizes and two different grain-size distributions to imbibe kerosene from the formation sand and release it to their respective wells. Treatments of different chemical products were applied to other filter sands to create a hydrophobic coating on the grains. The hydrophobic coatings were tested on filter sands of different grain sizes and grain-size distributions and compared to …


The Hydrogeology Of Bonnie Castle And Dustin Lakes And Its Relationship To Groundwater Contamination From The Kl Avenue Landfill, Kalamazoo County, Michigan, Joseph S. Hobin Jun 1993

The Hydrogeology Of Bonnie Castle And Dustin Lakes And Its Relationship To Groundwater Contamination From The Kl Avenue Landfill, Kalamazoo County, Michigan, Joseph S. Hobin

Masters Theses

The objectives of this investigation were to explain the hydrogeology of Bonnie Castle and Dustin Lakes and to assess the water quality of the lake environments with respect to possible impact from the KL Avenue Landfill.

The surface water/groundwater relationship was determined by the installation of mini-piezometer nests and seepage meters at selected study stations along the shoreline of each lake. Field data were augmented with groundwater and surface water chemical analyses, lake depth profiles and geologic cross-sections.

The result of this research was the characterization of Bonnie Castle Lake as a perched recharge lake and Dustin Lake as a …


A Fracture Analysis Of Glacial Tills In Southwest Michigan, Ralph L. Freed Jun 1993

A Fracture Analysis Of Glacial Tills In Southwest Michigan, Ralph L. Freed

Masters Theses

Fractures were recorded and measured at seven southwest Michigan glacial till locations to identify geometry and spacing. Strong preferred orientations were shown at azimuths of 110° and 140° for two sites, and at azimuths of 85°, 110°, and 135°, and at 44° and 167° for two sites. Several sites had numerous oblique fractures.

Thirty-eight azimuthal Wenner arrays and four Schlumberger surveys show apparent resistivities vary widely with depth of penetration and material composition. Eleven percent of azimuthal surveys show an elliptical data array coinciding with preferred orientation of an adjacent fracture set. The relationship between azimuthal survey and fractures is …


Using American Sign Language With A Direct Instruction Mathematics Program To Affect The Mathematics Achievement Of Deaf Students, Annette J. Bass Jun 1993

Using American Sign Language With A Direct Instruction Mathematics Program To Affect The Mathematics Achievement Of Deaf Students, Annette J. Bass

Masters Theses

The effectiveness of supplemental instruction using a scripted direct instruction program, Connecting Math Concepts (Englemann & Carnine, 1992), with four lower elementary deaf students was compared to the effectiveness of supplemental instruction in their traditional math curriculum, Mathematics Today (Abbott, 1985). A two-phase multiple baseline design across students was used. During the first phase, the students' achievement on curricula-based math probes was assessed while using the Mathematics Today as a supplement. During the second phase, the students' achievement was assessed while using Connecting Math Concepts as a supplement. The teacher presentation scripts in this program were translated into American Sign …


Signal Processing With Neural Networks, Pero Smrzlic Jun 1993

Signal Processing With Neural Networks, Pero Smrzlic

Masters Theses

In this study, we introduce the Adaptive Back Propagation (ABP) learning algorithm, computationally superior to the standard Back Propagation. The ABP is based on the new activation function, with its corresponding adaptive learning parameter. By using the combination of computer simulations and analysis in the domain of activation function, the Method of One Hidden layer was developed for the effective utilization of units in one-hidden layer networks. A parallel version of the ABP was designed and implemented on a nCUBE-2 supercomputer with 128 processors.

The simulation results suggested a strong correlation between frequency of signals and the role of hidden …


Topology Based Routing Algorithms For Multilayer Ic Layout Design, Moazzem Hossain Apr 1993

Topology Based Routing Algorithms For Multilayer Ic Layout Design, Moazzem Hossain

Masters Theses

In this thesis, we consider the multilayer topological routing problem and also the geometric routing problem based on topological routing solution. We show that the problem of multilayer topological planar routing for any arbitrary routing region can be modeled as a problem in a simple closed routing region. We also show that the solution to the multilayer planar routing leads to a better result of the topological via minimization problem. We present a provably-good approximation algorithm for the multilayer topological planar routing problem for different routing regions.

We also propose a graph theoretic algorithm to find 2-layer topological solutions that …


Middle Terminal Cell Models For Efficient Over-The-Cell Routing, Siddharth Bhingarde Apr 1993

Middle Terminal Cell Models For Efficient Over-The-Cell Routing, Siddharth Bhingarde

Masters Theses

In this thesis, we introduce a new class of cell models called Middle Terminal Models (MTM) which combines the advantages of existing cell models: BTM and CTM. This class contains the models 2MTM, 3MTM-V, and 3MTM+V depending on the number of metal layers and the permissibility of vias in over-the-cell areas. In MTM, two rows of terminals are located in the middle of the cell. This partitions over-the-cell area into three regions and allows allocation of more nets to over-the-cell area in congested channels. We prove that when vias are allowed over-the-cell, in "almost all" cases the MTM based layouts …


Story Writing By Students With Hearing Impairments, Lois A. Ketchum Apr 1993

Story Writing By Students With Hearing Impairments, Lois A. Ketchum

Masters Theses

Students with hearing impairments (N = 21) wrote a personal narrative each academic year from 1990 to 1992. These narratives were rated on maturity of the story as a whole and maturity of the language used in the story by senior undergraduate students in the education department at Western Michigan University. The method used for rating was a holistic magnitude estimation technique.

Significant change over time was found for story scores, but not language scores. Grade level was found to have no significant effect on change from first to last ratings for either story scores or language scores. Degree of …


Non-Resonant Transfer And Excitation For S^13+ Projectiles Colliding With Neutral Gas Targets, Liang Duo Apr 1993

Non-Resonant Transfer And Excitation For S^13+ Projectiles Colliding With Neutral Gas Targets, Liang Duo

Masters Theses

Non-resonant Transfer and Excitation (NTE) by 20-70 Mev S,3+ projectiles in collisions with neutral gas targets of He, Ne and Ar is investigated. For NTE, positively charged projectiles undergo excitation and electron capture in a single collision in which the capture and excitation processes are independent events. The mechanisms involved in the NTE process are electron-nucleus interactions, and the combination of projectile excitation and capture is a two-step process. In this work, NTE cross sections, along with total K x-ray production cross sections and total single-electron capture and loss cross sections, were measured as a function of projectile energy. The …


Improved Filter-Pack Design For Hydrocarbon Recovery Wells In Unconsolidated Aquifers, Thomas R. Barrett Apr 1993

Improved Filter-Pack Design For Hydrocarbon Recovery Wells In Unconsolidated Aquifers, Thomas R. Barrett

Masters Theses

Laboratory sand tank experiments and two field studies were conducted to determine filter-pack designs that would increase the hydrocarbon flow rate into hydrocarbon recovery wells. Previous laboratory experiments have shown that using filter-packs of Teflon chips or sands treated with a water repellent spray will increase the rate of hydrocarbon recovery into wells in laboratory bail down test experiments.

The results of the laboratory investigations suggest that using a hydrophobic filter-pack with a median grain-size of 2.5-3.5 greater than that of the aquifer will provide the greatest rate of hydrocarbon recovery.

In two field studies, wells constructed with a hydrophobic …


A Comparison Of The Hutchings’ Low-Stress, Factor Analysis, Hand-Held Calculator, And Conventional Addition Algorithms For Speed, Accuracy, And Preference With Regular Education Students, John C. Hampel Apr 1993

A Comparison Of The Hutchings’ Low-Stress, Factor Analysis, Hand-Held Calculator, And Conventional Addition Algorithms For Speed, Accuracy, And Preference With Regular Education Students, John C. Hampel

Masters Theses

Three repeated measures experiments were conducted to determine the efficiency with which medium and low math-achieving, fourth- and fifth-grade students computed two sizes of addition problems using each of four different algorithms. The experimenter selected the conventional algorithm and the hand-held calculator because they are currently in popular use. The experimenter selected the Hutchings' low-stress and factor analysis algorithms because of their demonstrated performance enhancing characteristics and unique design features. The three written algorithms represented a design continuum that facilitated a powerful deductive analysis.

In all conditions the Hutchings' low-stress algorithm produced incrementally superior performance consistent with its unique features. …


Impurity Modes In Photonic Band Structures, Yi-Fen Chang Apr 1993

Impurity Modes In Photonic Band Structures, Yi-Fen Chang

Masters Theses

In this thesis I study a theoretical model of one-dimensional dielectric array (a layered system of dielectric slabs) which forms a periodic dielectric system in which band gaps are opened in the frequency spectrum. Specifically, we study such a one-dimensional array with linear impurities introduced in the periodic dielectric system. In these impurity structures narrow resonant modes are found in the band gaps as impurity modes and these impurity modes change with the dielectric constant. This impurity problem is similar to the donor and acceptor state problem in electronic semiconductors. The calculations presented in this thesis are based on numerically …


Ground-Water Contamination By Volatile Organic Compounds: Sources Of Error, Temporal And Spatial Variability, Gary Thomas Blinkiewicz Apr 1993

Ground-Water Contamination By Volatile Organic Compounds: Sources Of Error, Temporal And Spatial Variability, Gary Thomas Blinkiewicz

Masters Theses

Data on the distributions of VOC’s (volatile organic compounds), principally trichloroethane and dichloroethylenes, in a shallow sand and gravel aquifer near Rockford, IL have been collected for a number of years. Synoptic sampling events from a dense monitoring well network within a greater than 4 mi^2 area, provide the basis for the evaluation of sources of variability in concentrations in space and time. Sampling, and analysis-related variability in these data contribute less than 10% of total variance. Spatial and temporal variability over periods of months to years are significant Results suggest that contaminant distributions can be resolved best by using …


Simulation Model For Predicting The Impact Of Progressive Diseases In The U.S. Population By Tracking, Biju Suseelan Apr 1993

Simulation Model For Predicting The Impact Of Progressive Diseases In The U.S. Population By Tracking, Biju Suseelan

Masters Theses

Computer Aided Simulation is the process of designing a mathematical-logical model of a real system and experimenting with this model on a computer. Simulation encompasses a model building process as well as the design and implementation of an appropriate experiment involving that model. A simulation experiment involves observing the dynamic behavior of a model by moving from state to state in accordance with well-defined operating rules designed into the model. This research contains the development of a novel approach for the HIV transmission dynamics by using computer simulation to track the HIV positive individuals in a population and to determine …