Engineering Commons^™

Development Of An Integrated Sensor For The Measurement Of The Acoustic Local Volume Displacement Of Vibrating Beams, Randall Rozema

Masters Theses

Currently, the methods used for sensing the volume displacement of a vibrating structure entail the use of a polyvinylidene fluoride sensor that spans the entire length of the structure. However, this work shows that the surface behavior related to volume displacement can be measured through the use of a polyvinylidene fluoride sensor that spans only the area of interest. In this application it was shown that two-point sensors are required in addition to the distributed, polyvinylidene fluoride sensor to achieve an accurate measurement. As a result, a set of four beams with different end conditions were constructed so that the …

Maximum Acceptable Oral Reading Speed For Voice Input Systems, Nirari M. Oda

Masters Theses

The objective of this thesis was to study the effect of vocal duration period and background noise on psychophysical oral reading speed. Ten healthy white males (21-28 years old) were used as subjects. Experiment one was designed to determine Maximum Acceptable Oral Reading Speed (MAORS) for an 8-hour period using psychophysical methodology. Results indicate that 114 words/min was an acceptable oral reading rate for an 8-hour day. Furthermore, 2 hours and 20 minutes is an acceptable testing period ( equivalent to the 8-hour day). Acoustical and physiological variables support these findings. Experiment two was designed to study the effect of …

Investigation Of Quantum Resistor Networks For Electron Wave Computing, Diwakar Ramamurthy

Masters Theses

A new computing methodology using electron waves has been developed with three and four terminal Quantum Resistor Networks as the basic computational structure. Transmission probability matrices for these networks were derived from first principles from which the behavior of single and simultaneously incident electron waves have been accurately evaluated. Classification and scaling laws have also been provided according to their transmission behavior. Techniques for constructing devices from these networks analogous to the logic gates used in digital computing today have been explained. Numerous examples of such devices performing functions like Inversion, OR, and AND have been provided. The operating principles …

A Dynamic Programming-Based Approach To Microarray Image Comparison And Registration, Sunil Bosco Rodrigues

Masters Theses

"Microarray technology is increasingly used as a means of high throughput analysis of human, non-human and plant genomes. Manual methods of array production have inherent imperfections and variations of the quality of output data derived from these arrays. A dynamic programming-based approach is presented to validate the quality of such data prior to insertion into evolving databases in order to assign reliably, genetic aberrations to bio-medical functions. Dynamic programming is used for comparing normal and tumor microarray image pairs and a cost function is developed which gives a value representing the difference between the images. Quality of the image pairs …

System Security In An Open Lab Environment, Erik Quist

Masters Theses

This thesis presents a system security process for computer workstations in a university open lab environment, which was developed and implemented for the Lumpkin Hall Computer Labs at Eastern Illinois University (EIU). The system security includes the use of policies and NTFS permissions, registry hacks and script files. These techniques were applied to a mixture of Windows NT 4.0 service pack 6a and Windows 2000 Professional workstations in the Lumpkin Hall Computer Labs. They were then tested for appropriate security setup using a Network Security Checksheet and a survey. The Network Security Checksheet ensured that all of the workstations were …

Effects Of Compression Processing Parameters And Antioxidants On Molecular Degradation Of Biodegradable Poly-L-Lactide (Plla), Thomas J. Hannan Jr.

Masters Theses

The purpose of this research was to find a combination of poly (L-lactic acid), also known as poly-L-lactide or (PLLA) and antioxidants that would, together, produce a product whose degradation rate would be advantageous for use in biodegradable medical implants. Intrinsic viscosity tests were conducted on compression molded samples of PLLA that were molded at various processing parameters in order to find optimal parameters. The optimal processing parameters were found to be time 10 minutes, temperature 220°C, and pressure 1000 psi.

The molecular weight of PLLA sample was taken while pressure, time, and temperature were varied. As pressure increased, no …

Prediction Of Airfoil Stall In Icing Conditions Using Wing Surface Pressures, Erik Pederson

Masters Theses

This thesis presents work on a Normalized Lift Coefficient instrumentation system that predicts airfoil stall in icing conditions. The system uses four surface pressures, measured aft of the ice formation, from which the aircraft's normalized lift coefficient is determined. The pressure port locations were selected such that the calibration algorithm remains nearly constant as the leading edge ice shape and thickness change. Data collected in the Western Michigan University Wind Tunnel is presented for three ice formations varying in both shape and thickness. The ice and no ice conditions were compared and a set of four ports was found that …

Texture And Young’S Modulus Of Nickel/Gamma-Alumina Composites, Abdulaziz Alamr

Masters Theses

To improve Young's modulus of 2024-T3 rolled aluminum specimens, it was electroplated with nickel reinforced with nano-particles of γAl₂O₃. Taguchi method was used to investigate the effect of coating variables, which were current density, coating time, and mixing rate, on the coating thickness. The coatings were tested for crystallographic texture, using pole figures of (200) and (111) for nickel and (400) for γAl₂O₃. Surface topography was measured using WYKO Vertical Interference Microscope. The crystallographic texture of nickel in the coating depended on the coating conditions. A universal testing machine was- used to …

Residual Stress And Wear Resistance Of Composite Coatings Of Nickel/Gamma-Alumina, Khaled Abdulrahman Al-Ogab

Masters Theses

Nickel reinforced with nanoparticles of γ−Al₂O₃ have been successfully codeposited on 2024-T3 cold rolled aluminum alloy by electrodeposition with direct current. The effects of current density, particle concentration in the nickel sulfamate bath, air agitation, and coating time on Ni/γ−Al₂O₃ composite have been investigated. The residual stresses and wear resistance of the Ni/γ−Al₂O₃ composite have been measured using X-ray diffractometer and pin-on-disk techniques respectively. The residual stress and wear resistance behavior of the composite were compared with those of nickel-only deposits. An annealed ground nickel, which was mechanically removed from the …

Small Below-Endurance-Limit Cycle Damage Contributions In Variable Sequence Loading For 2024-T351 Aluminum Alloy, Christopher M. Ngiau

Masters Theses

It is a common practice in industry today to totally discard the presence of small below-endurance/fatigue limit cycles while calculating damage accumulation using the Palmgren-Miner rule. However, it was experimentally found in a number of studies that small cycles with stress amplitudes below the fatigue/endurance limit do in fact contribute significantly to the damage accumulation in all types of materials. There was a need to investigate cases where small cycles would only be present for a certain percentage of the material's life. An experimental study was done on 2024- T351 aluminum alloy. Loading was done in low and high cyclic …

The Development Of A Fmea Process For Design And Maintenance, Tearesa Lynn Wegscheid

Masters Theses

Failure Modes and Effects Analysis (FMEA) is a systematic way to identify and evaluate potential product and process related failure modes, the associated causes of failures, and the necessary actions to eliminate or reduce the chance of the failure. There are a number of published manuals and books on FMEA. The materials provide a definition of the FMEA form and examples of the Design and Process FMEA. However, there are many inconsistencies throughout the literature. As a result, FMEA is not always value-added.

The thesis is twofold. First, it documents a case study that uses Design FMEA extensively. The case …

Cfmms – Computerized Facilities Maintenance Management System, Prawit Rotsawatsuk

Masters Theses

Computerized facilities maintenance management systems, previously available only to very large facilities, are now accessible to small and medium-sized maintenance organizations. Advertisements for such products promise reductions in maintenance costs. Where a manual system of maintenance management is currently employed, moderate reductions in maintenance costs and facility downtime are fully possible. Where no formal maintenance management procedures are present, the structure and case of a computerized maintenance system can result in dramatic cost reductions and improvements in facility availability. There are, however, practical limits to the applicability of computerized maintenance systems. The objective of any maintenance program is to minimize …

A Cmos Chaotic Oscillator, Boonsin Chansilp

Masters Theses

A chaotic oscillator may be used as the basic component of an associative memory (AM). An AM is capable of pattern separation and noise reduction. Chua's circuit is a widely used chaotic oscillator. This circuit consists of a nonlinear resistor, two capacitors, an inductor and a resistor. A discrete implementation of Chua's circuit may be built using operational amplifiers, resistors, diodes, or discrete bipolar transistors. CMOS integrated circuit technology provides the opportunity for a compact implementation which enables construction of systems requiring a large number of oscillators. This thesis develops an integrated circuit design based on previous work performed by …

Learning Reinforced Concreyte Design Principles Using A Java-Vrml Based Design Studio, Amarneethi Vamadevan

Masters Theses

Dynamics involving reinforced concrete design are the first real engineering course encountered by the undergraduate construction engineering students. Quite often its associated rigorous theories makes it an uninteresting academic hurdle for many below mediocre students. However when the theory is exemplified with multimedia, interaction and visualization techniques, the conceptual understanding is enhanced. The teaching methodology presented in this thesis is based on presenting students with an individualized, interactive and guided learning environment. The main elements of this approach are: a means of assimilating the student's interactive learning knowledge and behavior (user model), representation of the instructor's guidance and assessment knowledge …

A Neural Network Methodology For Path Planning And Coordination Of Car-Like Robots, Prasanna Venkatesan Sadagopan

Masters Theses

"A car-like indoor mobile robot is a kinematically constrained robot that can be modeled as a 2D object translating and rotating in the horizontal plane among well- defined obstacles. The kinematic constraints impose that the linear velocity of the robot is along its main axis (no sideways motion is possible) and restrict the range of admissible values for the steering angle. The goal of this study is to combine neural network techniques and motion planning algorithms to create a new methodology for coordinating the motion of multiple car-like robots avoiding collision with polygonal obstacles in a work environment. An incremental …

Effect Of Antioxidants On Ultra High Molecular Weight Polyethylene (Uhmwpe), Clifford Schrader

Masters Theses

This thesis presents a study on the effects of antioxidants on the oxidative induction time (OIT), thermal behavior, and hardness property of ultra high molecular weight polyethylene (UHMWPE). The antioxidants were dissolved into methanol alcohol before the solution was mixed with UHMWPE powder. The mixture was degassed under vacuum, and then compression-molded into disks 1.25 in. in diameter.

Different antioxidants were evaluated at concentrations up to 0.6 percent. A 0.6 percent concentration was used to screen the effectiveness of various antioxidants. Effect of antioxidant concentration was investigated in the range between 0 and 0.6 percent. OIT was evaluated on UHMWPE …

Cellular Automata Study Of The Feasibility Of A Parallel Optical Computer, Jason Robert Lane

Masters Theses

"The speed of modern electronic computers has inherent design limitations which will soon be reached. A possible substitute is the optical computer. In this project, the feasibility of the optical computer is explored by designing and building a parallel optical system. This system is used to test the basic principles that would govern a parallel optical computer. The system is based on the principle of cellular automata, which is a simulation technique used to study interactions of objects in a system. The following goals were set. The system would be based on cellular automata. A one-dimensional array with nine cells, …

Reconstitution And Characterization Of Membrane Proteins, Sarah Mia Pates

Masters Theses

“A membrane protein, cytochrome c reductase, was crystallized and examined using transmission electron microscopy. Two-dimensional crystals were prepared by two methods. In Method 1, the protein was solubilized in 50 mM Tris-Acetate (pH 6.0)/0.5 mM EDTA70.05% (w/v) Triton X-100 and reconstituted into a mixture of phosphatidylcholine and phosphatidylserine (4:1), dissolved in the same buffer. The Triton X-100 was removed from the mixture by dialysis in the presence of Bio-beads (SM-2) at approximately 25-30 °C. Method 2 was the same as Method 1, except that the vesicles were fractionated before reconstitution, and the pH and temperature for crystallization were 7.0 and …

Investigation Of Pattern Classification And Feature Selection Of Gaussian Processes, Vivek Ramaprasad

Masters Theses

"This thesis focuses on the application of statistical techniques for pattern classification where the patterns are power spectra of the recorded acoustic signals of occluded objects. Different approaches used to classify are : The Bayes linear and piece-wise linear classifiers, the correlation classifier, classification using error spectra and the clustering algorithm. Classifiers were designed and experiments were conducted to investigate the performance. The performance is evaluated in terms of the percentage efficiency by counting the number of vectors identified correctly and the number of vectors which were misclassified. The feature vectors from primitive measurement space is then reduced to lesser …

Quantifying A Key Injection Molding Attribute Defect, Kristopher Bryan Horton

Masters Theses

A mounting demand for high quality, low cost plastic injection molded products brings with it goals such as low or even zero defects. In order to achieve these types of "world class" expectations, resources are used to monitor and control variable data such as cycle time, part weight or dimensions. Despite this emphasis on variable data, parts are often rejected based on attribute molding defects such as sink marks or splay that are measured by subjective criteria and therefore difficult to control. Appearance of a part once considered acceptable may no longer be, due to changing expectations or subjective interpretation …

Epoxy-Terminated Self-Assembled Monolayers As Molecular Glues For Polymer Layers, Duangrut Julthongpiput

Masters Theses

Dense, homogeneous, and complete self-assembled monolayers (SAMs) with epoxy surface groups were fabricated from epoxysilanes to serve as a template for chemical anchoring of polymer layers. A combination of scanning probe microscopy, ellipsometry, XPS, X-ray reflectivity, and contact angle measurements was used to study their morphology and surface properties. Self-assembly of epoxysilane molecules resulted in the formation of homogeneous SAMs 0.85 nm thick with the rms surface roughness 0.2 nm. Epoxysilane SAMs were truly monomolecular films with a virtually normal molecular orientation of densely packed molecules, which were firmly attached to the substrate.

Carboxylic acid and anhydride terminated polystyrenes of …

Development Of Mechanical Properties Micromapping For Composite Polymer Systems, Zheng Huang

Masters Theses

By adoption of classic indentation models (Hertzian, modified Hertzian, Sneddon, JKR), the elastic properties of polymeric material can be measured by AFM. Heterogeneous thin films were fabricated from polymer blends with a wide range of Young's moduli and thermal transition temperature to test the developed procedure. Results show that the micromapping of elastic properties can be obtained concurrently for glassy and rubber phases as well as across the interface with a lateral resolution better than 100 nm. Application of the elasticity micromapping on heterogeneous polymeric materials reveals thermal transition temperature that coincides very well with bulk values. Depth profile also …

Conform- A Computerized Job-Built Concrete Construction Formwork Design, Kajpong Pongponrat

Masters Theses

Economy in formwork design depends partly on the ingenuity and experiences of the form designer, whether a contractor or an engineer. The cost of formwork is significant, generally amounting to anywhere from 40% to 60% of the cost of a concrete structure. Judgment with respect to the development of a forming system could both expedite a project and reduce costs. The present paper addresses the development of CONFORM - an interactive menu driven PC based job-built concrete formwork design. The system is developed using Microsoft Visual Basic 6, Access 97 database, and Word 97, where a perfect integration of these …

Quantitative, Non-Destructive Calibration Of Scanned Probe Microscope Cantilevers, John Hazel

Masters Theses

Principles of surface science and engineering are applied to determine scanned probe microscope cantilever spring constants. The bi-component gold-ceramic cantilever composition is modeled analytically. Finite element analysis is applied to simulate deflection behavior of the probe tip. Data from experimental determination of resonant frequency are employed to infer material characteristics. Combination of the results from these three procedures is employed to infer material characteristics. Combination of the results from these three procedures is used to produce a spring constant assessment within 10% of actual values. An additional convenient program for assessment of scanning probe microscopy cantilever spring constants is developed …

Intellicranes – A Neural Network-Based Crane Selection System, André T. Mund

Masters Theses

Due to the central role of cranes in construction operations, specialists in the construction industries have cooperated in the development of structured methods and software for crane selection. Most of these software tools are for crane model selection and query the user for the type of crane to be used. Although research produced some fuzzy logic and expert system-based methods for crane type selection, no integrated systems that handle both crane selection phases are available.

IntelliCranes, a prototype integrated crane selection tool, assists in both crane type and crane model selection based on a set of inputs describing the construction …

Optimization Of Insertion Holes And Anchor Design For Cylinder Shaped Toggle Type Suture Anchors, Adam Fedenia

Masters Theses

This research was performed to optimize insertion holes and anchor design for cylinder shaped toggle type suture anchors. Four types of anchors were investigated in terms of pull strength and design in acrylic plate and pig bone. They included small type A and B anchors and large type A and B anchors.

Pull strength trends suggest that the small type anchors behave similarly since their external dimensions are identical, with the exception of type A anchor having a hole running from one end of the cylinder to the other like a pipe. It was found that the suture would fail …

The Hygrothermal Response And Physical Aging Of Polymer Matrix Textile Composites, Natalie L. Dixon

Masters Theses

"Woven graphite/epoxy composite laminate is one type of composite currently being investigated for use in aircraft engine components. However, polymers tend to become brittle with age, especially when exposed to elevated temperature. It is necessary to understand the physical changes in a material during the aging process in order to predict the long-term behavior.

In addition to aging, materials used in aircraft will be exposed to a wide variety of temperatures and relative humidity levels. Variations in temperature and moisture content affect both the physical and the mechanical properties of composites.

Experimental methods are described for hygrothermal testing of a …

Fitness Landscape Analysis Of Discrete Constrained Optimization Problems, Sai Prasanna Ravichandran

Masters Theses

The exponentially large size of the solution space of typical optimization problems precludes the use of any deterministic approach to search for an optimal solution. A more efficient and efficacious approach is to use heuristic algorithms based on rules of thumb to guide the search process in the solution space. Associated with every solution in the space is a real number called fitness that signifies the quality of a solution. This space and the fitness values together form the fitness landscapes. Knowledge about the topology of these fitness landscapes is vital for any heuristic search operator to expedite the search …

Adaptive Channel Equalization Techniques, Saied Razavilar

Masters Theses

Inter Symbol Interference (ISI) is a characteristic of band-limited communication channels that can severely degrade the digital communication system performance if not treated properly. Channel equalization techniques may be used to mitigate the effects of ISI in the system, thereby improving the system capacity and performance. In this thesis, the problem of Inter Symbol Interference caused by the nonlinear characteristics of band limited communication channels and adaptive equalization techniques to combat the effects of ISI are discussed. First, the analysis of ISI in a band limited communication channel using a concrete theoretical framework is presented. Next, various adaptive equalization techniques …

An Analysis Of Texture Resulting From Thermomechanical Processing Of Ti-6al-V, David J. Brock

Masters Theses

An investigation of texture and microstructure formation in Ti-6Al-4V after thermomechanical processing and heat treating was performed. X-ray diffraction was used to measure prismatic and pyramidal pole figures. These pole figures were used to calculate basal pole figures, which showed significant changes in texture from heavy rolling and near or above β-transus heat treatments. Primary texture components were found to be strengthened by near β-transus heat treatments. For heavily rolled material, above β-transus heat treatments were found to reverse the primary texture components order of dominants. Heavy rolling was found to reduce the RD component and strengthen the TD.