Mechanical Engineering Commons^™

Viability Of A Proposed Transparent Fluid Model For Analog Metal Casting Filling Process, Andres Segura Irazoqui

Dissertations and Theses @ UNI

No abstract provided.

Investigating The Production Of Cores By Using Reclaimed Foundry Green Sand, Kristopher Lee Boss

Dissertations and Theses @ UNI

Increasing environmental regulations, transportation cost, delivery interruptions leading to production concerns, disposal cost, and demand from other industries have influenced the way foundry’s view used sand. The purpose of this research was to determine a beneficial reuse of overflow-green sand that would normally be disposed. The reclamation process used is a combination of mechanical and wet reclamation. The focus was on the production of foundry cold box cores and if using this reclamation process could create a core with a similar quality performance compared to new sand. Research in reclamation could pave the way for a closed loop sand system, …

How Quality Management Has Been Impacted In The Face Of Covid-19, Eldina Siljkovic

Dissertations and Theses @ UNI

The Coronavirus pandemic has impacted many facets of the United States. This study focuses on its magnitude in comparison to prior pandemics such as Anthrax, SARS, and Ebola. In addition to this comparison its impact on Quality Management within the agricultural sector and food supply chain was also assessed. The results of these studies showcase that COVID-19 has grown exponentially in comparison to prior pandemics and will continue to do so as we enter the winter season. Agricultural equipment manufacturing companies saw a drastic decline in quarterly revenues within 2020 in comparison to 2019. Millions in net sales were lost …

3d Printed Relief Valve Analysis And Validation, John Anthony Dutcher Iii

Dissertations and Theses @ UNI

Additive Manufacturing allows for faster, lower cost product development including customization, print at point of use, and low cost per volume produced. This research uses Stereolithography produced prototypes to develop an improvement to an existing product, the internal pressure relief valve of a positive displacement pump. Four 3D printed prototype assemblies were developed and tested in this research. The relief valve assemblies consisted of additive manufacturing produced pressure vessel components, post processed, and installed on the positive displacement pump with no additional machining. Prototype designs were analyzed with Computational Fluid Dynamic simulation to increase flow through the valve. The simulation …

Development Of A Hydraulic Component Leakage Detecting System Using Pressure Decay Signal, Xuanju Shang

Dissertations and Theses @ UNI

It is preferable to detect leakage at the earliest phase in the manufacturing process, and then further assembly of hydraulic components with leakage problems can be avoided. Integrating a USB based microcontroller and a pressure sensor; this study developed a hydraulic leakage detection system in using air instead of hydraulic oil as medium, through measuring pressure decay signals captured by a real time data acquisition system. Compared with the conventional hydraulic system using oils, this system shows advantages in safety operation and little environmental concerns due to use a lower pressure clean air.

The low-cost hydraulic leakage detection system was …

Analysis Of Factors Causing Failure Mode For Automotive Hitch Control System Calibration In Agriculture Equipment, Setordji Yao Abotsi

Dissertations and Theses @ UNI

Traditionally, agricultural tractors have used hydro-mechanical draft control systems to mechanically sense implement draft. Technological development of low cost, reliable microprocessors has contributed to allowing greater flexibility in designing agricultural tractor control systems (Rutkowski & Welchens, 1986). To successfully control the depth of which an implement penetrates the ground, it has become imperative to incorporate a draft control system on agricultural tractors. The control system operates by responding to the draft load or force acting on the tractor. Increasing the draft load or force allows the implement to be raised and decreasing the draft load or force allows the implement …

Perceived Importance Of National Occupational Cadd Skill Standards Among Faculty Of Nait Accredited Institutions, Ronald Shava

Dissertations and Theses @ UNI

This study presents a descriptive survey that examined the importance and relevance of National Occupational CARD Skills based on the perceptions of faculty teaching at National Association of Industrial Technology (NAIT) accredited institutions. The major goal of the study was to determine what National Occupational CADD Skill Standards are relevant and important to faculty teaching CARD courses. The study was also designed to determine ratings of the perceived importance and relevance of National Occupational CADD Skill Standards by faculty teaching CADD courses at NAIT accredited institutions based on their area of specialization, professional ranking, and teaching experience. This study provided …

Building A Comprehensive Energy Model For Off-Highway Vehicles With Emphasis On Vehicle Thermal Control Systems, Ayhan Zora

Dissertations and Theses @ UNI

Utilizing machine and thermal system simulations (vehicle energy models) can be very helpful for vehicle manufacturing companies to develop a machine with acceptable component temperatures, less heat loads to the vehicle cooling systems, and reduced emissions that will also reduce overall product development cycle.

Energy models of vehicles were developed mostly in the automotive industry, and most of these studies were based on partial energy models.

The aim of this research study was to create a comprehensive energy model for agricultural machinery, which will be a basis for future work on similar products. A tractor model from a Midwest off-road …

The Design And Evaluation Of A Plc-Based Model Predictive Controller For Application In Industrial Food Processes, Bryan T. Griffen

Dissertations and Theses @ UNI

Model Predictive Control (MPC) is a viable control strategy for industrial processes that display relatively large variations in the process variable, have complex process variable interactions, or display a large amount of process deadtime. The objective of using MPC in manufacturing is to reduce overall process variability, the result being an increase in process accuracy, precision and efficiency. This study focused on the implementation of model predictive control techniques on an industrial sugar cooking process. The goal was to implement a successful MPC solution directly on a programmable logic controller (PLC) rather than on a personal computer (PC). Although there …

The Effects Of An Interactive Computerized Multimedia Tutorial On Knowledge Gain In Modular Fixturing Design Concepts, Veekit O'Charoen

Dissertations and Theses @ UNI

This study was designed to compare student knowledge gain from learning modular fixturing design concepts by computer tutorial versus traditional lecture. The use of computer tutorial to support engineering and technology classroom instructions has been a major issue for many studies. The undergraduate curricula in engineering and technology are becoming increasingly complex due to the today's modern wide variety of manufacturing processes. The concept of modular fixturing in tool design course is one of the technical competencies which most industries would like graduates to be able to apply their knowledge to real-world problems and situations.

An interactive computerized multimedia tutorial …

The Effect Of Heat On Fingertip Sensitivity Of Meat Processing Workers, Brian James Finder

Dissertations and Theses @ UNI

Current research indicates that acute non-freezing cold exposure elicits short-term performance problems; namely reduced upper extremity temperature, blood flow, tactile sensitivity, and dexterity. However, various animal-related studies indicate that humans are at increased risk of incurring semi-permanent upper extremity nervous system dysfunction as a result of repeated cold exposure.

The purpose of this research was to examine various factors that may contribute to hand/arm nervous system impairment of individuals who work in a refrigerated meat-processing environment. The methodology used was primarily the Experimental Method and from studies conducted by other researchers, was driven by the following questions:

(1) How would …

A Leadership Model And Supervisory Skills Perceived By Production Employees, Supervisors, And Managers As Important To The Improvement Of Employee Performance In Manufacturing, Douglas R. Hotek

Dissertations and Theses @ UNI

The purpose of this research was to provide to industry and education a better understanding of what makes a supervisor a good supervisor of today's educated and technically skilled work force. Manufacturing firms that depend on advanced technologies and employee-technology relationships have made an impact on the role of supervision. The modern supervisor has a new role in managing production operations. The role has changed from that of directing and controlling employees to that of effectively leading the improvement of employee performance. This study builds upon previous research in an effort to further identify and authenticate a leadership model with …

Simulation Of Optimal Drive Systems Consisting Of Gear-Cam Mechanisms With Brushless Dc Servomotors, Norbert Fritz

Dissertations and Theses @ UNI

This study presents the development of flexible tools for the numerical simulation of processing machine drives that consist of servomotors, mechanisms, and machine tools. The simulation allows predicting the motions or vibrations of linkages, forces and torques in joints, motor currents, and system response times as well as evaluating stability and characteristic frequencies of the drive system The simulation tools were implemented as macro components in macro component libraries using the EASY5* Dynamic System Modeling, Simulation, and Analysis software by the Boeing Company. Application of the developed macro components allows fast and efficient modeling of a variety of different drive …

An Evaluation Of The Aws Entry Level Welder Training Program, John R. Rice

Dissertations and Theses @ UNI

The purpose of this study was to evaluate the effectiveness of a training program for Entry Level Welders and to provide this information to the American Welding Society (AWS), industry, and educators. The problem of this study was to evaluate the AWS Entry Level Welder Training Program (ELWTP) by obtaining the opinions of faculty members who taught the program and welders who had completed the program.

Two groups comprised the research population for this study. The first group consisted of faculty members who were actually involved in teaching the course at institutions accredited by the AWS to offer the curriculum. …

A Design Of A Marine Radar Mast System For Minimum Vibration, Suey-Yueh Hu

Dissertations and Theses @ UNI

This experimental research focused on four areas: (a) the design of a new procedure for imitating the dynamic behavior of an electronic base plate on a radar mast system; (b) determination of a reasonable oscillation modal state; (c) avoidance of the destruction of the ability of the radar on the mast of a ship to receive and analyze incoming signals; and (d) design of a vibration absorber and vibration isolator based on an oscillation frequency. An adapted design for the vibration absorber and vibration isolator contributed to the prevention of excessive amplitude being produced by random forces acting upon a …

An Investigation Of Diameter Measurement Repeatability Using A Coordinate Measuring Machine And A Multi-Baseline Repeatability Assessment Methodology, Bruce Marsh

Dissertations and Theses @ UNI

The need for reliable and consistent measurement has become more acute with the use of statistical process control (SPC), gage repeatability and reproducibility (Gage R&R) assessment, and high precision, computer-controlled gaging systems. Although it is often overlooked, the inspection methodology under which various features are inspected has an impact on Gage R&R results. This notion was confirmed when a 1993 thesis study substantiated inspection methodology as a source of measurement variability in direct computer-controlled, coordinate measuring machines (DCC/CMMs). Although this study explored a methodology to bring measurement variability under statistical control, the tested assessment methodology--single baseline repeatability assessment--was not validated. …

Toward The Optimization Of Cell Operator Productivity In Computer Integrated Manufacturing, David Leonard Gobeski

Dissertations and Theses @ UNI

Computer integrated manufacturing (CIM) has been seen as the answer to maintaining the lead in American productivity. The cell operator was seen as being critical to the success of CIM. The design of the operator's job was seen as very important. As manufacturing engineers design cell jobs, including the roles and tasks, with the operators, it was believed important for the engineer to know what motivated the cell operator. However, past studies of supervisors and their subordinates have shown that supervisors are unable to predict the importance of the elements of job enrichment of the subordinates. It was questioned whether …

The System Design And Evaluation Of A Microprocessor Controlled Dispenser Using A Radar Ground-Speed Sensor, Yu-Charn Chen

Dissertations and Theses @ UNI

This experimental research focused on the design of a new approach to control seed dispensers and to analyze the performance characteristics of a Doppler radar ground speed sensor for a microprocessor control dispenser. The research focused on comparing the effectiveness of using a radar unit with a fifth-wheel encoder for measuring ground speed when both were connected to a microprocessor controlled seed dispenser.

The system designed for this study consisted of hardware and a computer program in 6502 assembly language. The hardware for this study consisted of a monitor device, microprocessor control unit, stepper motor, fifth-wheel encoder, Doppler radar and …

An Experimental Cost Model For The Analysis Of Quality Cost In A Manufacturing Enterprise, Wallace Charles Carlson Jr.

Dissertations and Theses @ UNI

The intent of the study was to construct a quality cost model for manufacturing enterprises. A quality cost model provides a manufacturing enterprise with a cost structure which enables it to gauge and measure the efficiency and effectiveness of its management and processes. The quality cost model was specifically constructed to aid a manufacturing enterprise in establishing a quality cost system for its operations and activities and contains three distinct initial implementation or decision areas; the quality cost management decisions area, the quality cost system applications area, and the quality cost system utilization area.

The quality cost model was evaluated …

Relationships Between Selected Features Of Helical Or Spur Gears And Size Distortions Due To Heat Treatment, Abolghassem Tolu Honary

Dissertations and Theses @ UNI

The purpose of this study was to determine the relationships between selected gear features and distortions due to heat treatment. An extensive review of the literature indicated that studies on gear distortions were mainly metallurgically oriented, and the relationships between gear geometrical features and dimensional distortions due to heat treatment had not been investigated.

This investigation obtained data from actual gear size adjustments that had been collected from many years of experimentations at the John Deere Component Works (JDCW), Waterloo, Iowa. Gear data were converted to uniform files and were classified, retrieved, and analyzed by computerized systems. Two groups of …