Engineering Commons^™

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 …

25th Conference On Senior Engineering Design Projects, College Of Engineering And Applied Sciences

Senior Engineering Design Conference

The 25th Conference on Senior Engineering Design Projects was held on November 30, 1999 at the College of Engineering and applied Sciences on the Parkview Campus of Western Michigan University. The college sponsors the conference to showcase the work of its graduating seniors, who are required to complete a capstone project that puts into practice what they have learned. Many of the projects are sponsored by business and industry.

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 …

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 …

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 …

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 …

Active Local Volume Displacement Cancellation Of A Vibrating Baffled Beam, Marcellin Zahui

Dissertations

An active noise control apparatus is developed. The device reduces the sound radiated from a vibrating clamped beam. The attenuation of the sound field is obtained through minimization of local volume displacements of the vibrating beam. Two single-input/single-output cancellation devices are used. Each device employs a motion sensor and an acoustic actuator. The actuator is a loudspeaker equipped with a pressure sensor to detect its volume displacement. The motion sensor signal is related to the local volume displacement of the structure which is then reduced by a loudspeaker driven with an equal but opposing volume displacement. The volume displacement sensors …

Intellicrances – 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 …

24th Conference On Senior Engineering Design Projects, College Of Engineering And Applied Sciences

Senior Engineering Design Conference

The 24th Conference on Senior Engineering Design Projects was held on April 13, 1999 at the College of Engineering and applied Sciences on the Parkview Campus of Western Michigan University. The college sponsors the conference to showcase the work of its graduating seniors, who are required to complete a capstone project that puts into practice what they have learned. Many of the projects are sponsored by business and industry.