Mechanical Engineering Commons^™

Development Of Phase Change Thermal Storage Medium: Cooking With More Power And Versatility, Martin Osei

Masters Theses

With an Insulated Solar Electric Cooker (ISEC), a 100 W solar panel directly cooks food while providing 5W off-grid electricity access; but it cooks slowly. Storing the day’s energy with phase change thermal storage allows ISEC to cook more rapidly as well as cook after sunset. The ISEC is made by sticking a 3ohm resistive to an aluminum pot (inner phase change assembly PCA) where another cooking pot fits. The resistive heater is surrounded by a bigger pot (outer PCA) that contains the PCM and is tightly sealed. The solar panel is connected to the resistive heater with a thermal …

A Study Of Acoustic Reflections To Determine The Location, Size, Shape, And Orientation Of Reflecting Objects, Brandon M. Heller

Masters Theses

This study was conducted to examine the properties of sound in relation to echolocation, specifically in relation to its use by humans. Through my thesis, objects of varying shape and size were subjected to a sound wave to determine details about the object from the reflected sound. The shapes' comparisons were conducted at varying distances, measuring the intensity of the returning sound wave at several frequencies. The results demonstrated a correlation between the intensity of the sound in regards to distances, area of the reflector, and the shape of the reflector.

Development Of Learning Objectives For An Undergraduate Computer-Aided Drafting And Design Animation Using The Delphi Technique, Gavin M. Wilk

Masters Theses

This study reflects on learning objectives created for an advanced computer aided drafting (CAD) learning module(s) or course with the emphasis on simulation and engineering animations. These objectives were derived by using the Delphi technique by access the support of a panel of subject matter experts (SME) from academia and industry that are interested in CAD. The results of this study are intended for the use of creating instructional modules for undergraduate studies.

A panel of experts were chosen through an electronic listserv of engineering and technology supporters. Two rounds of two different Delphi survey instruments were utilized to complete …

A Comparison Of The Level Of Maturity Of Manufacturers In The Lake Land College School District In Lean Manufacturing Techniques As Compared To Goodson's Survey Data, Mark W. Henderson

Masters Theses

The purpose of this study was to determine if manufacturers in the Lake Land College School District have implemented Lean Manufacturing techniques and score as high as the manufacturers in Goodson's Michigan study. Lean Manufacturing techniques have revolutionized the auto industry, with the Toyota Production system the benchmark in Lean Manufacturing techniques. A survey using Goodson's Rapid Plant Assessment compares the level of maturity in the utilization of the Lean Manufacturing techniques with the manufacturers in the Lake Land College School District and Goodson's survey of manufacturers in Michigan. The mean score of 57.67 for the manufacturers in the Lake …

The Effects Of Machining On Structure And Tribological Properties Of Ultra High Molecular Weight Polyethylene For Artificial Joint Prostheses, Jinshan Song

Masters Theses

Understanding the effect of machining on the structure and property of subsurface layer of ultra high molecular weight polyethylene (UHMWPE) can significantly facilitate the increase in longevity of artificial joints. This study was performed to investigate the machining effects on the polymeric structure and tribological properties. Machining parameters include cutting speed, tool feed rate and depth of cut. Temperature rise was studied during machining to assess the extent of thermal degradation due to machining. Polymeric structure of the semicrystalline polymer was characterized using differential scanning calorimetry (DSC) in terms of melting enthalpy, crystallinity and melting temperature. Surface texture and hardness …

Mechanical And Tribological Properties Of Composites Of Recycled High Density Polyethylene And Recycled Rubber, Jason G. Boulanger

Masters Theses

This thesis presents a study on the mechanical and tribological properties of composite materials of recycled high density polyethylene (HDPE) and recycled rubber tire particles. The materials were compounded by extrusion and formed into test specimens by injection molding.

The first experiment studied the effect of recycled rubber percentage on mechanical properties of composites of recycled HDPE and recycled rubber. The mechanical properties included tensile strength, percent elongation, hardness, and impact resistance. Recycled rubber concentrations of 0, 5, 10, 15, 20, 25, and 30 percent were tested. The second experiment investigated the tribological properties of recycled HDPE and recycled rubber …

Investigation Of Electrotribological And Arc Erosion Behavior Of Cu-15vol.%Cr In Situ Composite, Zhongyu Chen

Masters Theses

Electrotribological and arc erosion behavior of Cu-15vol.%Cr in situ composite was investigated in terms of coefficient of friction, interfacial resistance, bulk temperature, and wear rate as a function of normal pressure, sliding speed, and electrical current. Microstructural change due to electrical sliding was studied to understand wear mechanisms. Cu-15vol.%Cr in situ composite was selected in this research because it exhibits an excellent combination of mechanical strength and electrical/thermal conductivity.

It was found that the average coefficient of friction decreased with increasing electrical current under dry electrical sliding. The average coefficient of friction was lower under lubricated electrical sliding than that …