Engineering Commons^™

Nebraska Summary: S128 Massey Ferguson 393, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Nebraska Summary: S127 Massey Ferguson 253, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Nebraska Summary: S129 Massey Ferguson 396, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

Approaches To Control Of The Large Angle Magnetic Suspension Test Fixture, Mehran Ghofrani

Mechanical & Aerospace Engineering Theses & Dissertations

The Large Angle Magnetic Suspension Test Fixture is a five degree-of-freedom system, developed and built at NASA Langley Research Center. It is intended for study of control techniques in magnetic suspension systems with large angular capabilities. In this study, steps have been taken to prove the system in practice, using the existing hardware. A classical control approach, using dual phase advance compensators, is applied in simulation and hardware. A single decoupled degree-of-freedom of the system is stabilized and controlled in simulation. The procedure is then employed for all five degrees-of-freedom. The design and implementation of an analog and a digital …

Measurement Of The Coefficient Of Thermal Expansion Of Superconducting Thin Films Using Powder X-Ray Diffraction, Biju Chandran, R. Calvin Goforth, S. Nasrazadani

Journal of the Arkansas Academy of Science

The High Density Electronics Center (HiDEC) at the University of Arkansas, Fayetteville is developing the technology for High Temperature Superconductor Multi-Chip Modules (HTSC-MCM's). As part of this work, we are looking at the mechanical properties of HTSC materials. An important mechanical property which influences the mechanical integrity of the hybrid MCMis the coefficient of thermal expansion (CTE) of the HTSC films. As a first step in developing a procedure for the determination of the CTE of HTSC materials, the lattice parameters and the CTE of an alpha-alumina substrate have been determined by powder x-ray diffraction technique. An extension of this …

Extension Of Vlasov’S Semi-Membrane Theory To Reinforced Composite Shells, Victor Birman

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Governing equations for the statics and dynamics of reinforced composite shells are developed based on Vlasov's semi-membrane shell theory. These equations have closed-form solutions illustrated for buckling and free vibration problems. The buckling solution converges to the known result for unstiffened isotropic shells. © 1992 by ASME.

Machining Of Composite Materials. Part I: Traditional Methods, Serge Abrate, D. A. Walton

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Composite materials are more difficult to machine than metals mainly because they are anisotropic, non-homogeneous and their reinforcing fibers are very abrasive. During machining, defects are introduced into the workpiece, and tools wear rapidly. Traditional machining techniques such as drilling or sawing can be used with proper tool design and operating conditions. A review of traditional machining methods applied to organic and metal matrix composites is presented in this article. The use of non-traditional machining methods such as waterjet, laser and ultrasonic machining will be discussed in the second part. © 1992.

Effect Of Temperature On The Ultimate Strength And Modulus Of Whisker‐Reinforced Ceramics, Douglas R. Carroll, Lokeswarappa R. Dharani

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Whiskers are a very attractive means of reinforcing a ceramic material. It has been shown that the whiskers dramatically improve the ultimate strength and modulus of the materials at room temperature. However, recent studies indicate that at high temperatures the improvement is less pronounced, or there is no improvement at all. In this paper a model is developed to explain why the properties are degraded at high temperature. The parameters which seem most important for high‐temperature performance are the coefficients of thermal expansion and Poisson's ratios for the constituents, the heat treatment temperature, and the coefficient of friction between the …

Analysis Of Shear Bands In Simple Shearing Deformations Of Nonpolar And Dipolar Viscoplastic Materials, R. C. Batra

Mechanical and Aerospace Engineering Faculty Research & Creative Works

During the past few years, we have studied numerically the initiation and growth of shear bands in nonpolar and dipolar viscoplastic materials being deformed in simple shear, and in nonpolar materials undergoing plane strain deformations. We summarize here our work for the former problem. © 1992 American Society of Mechanical Engineers.

A Complete Model Characterization Of Brushless Dc Motors, N. Hemati, Ming-Chuan Leu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The authors address the modeling problem associated with brushless DC motors (BLDCMs) with nonuniform air gaps that operate in a range where magnetic saturation may exist. The mathematical model includes the effects of reluctance variations as well as magnetic saturation to guarantee proper modeling of the system. An experimental procedure is developed and implemented in a laboratory environment to identify the electromagnetic characteristics of a BLDCM in the presence of magnetic saturation. It is demonstrated that the modeling problem associated with the class of BLDCMs can be formulated in terms of mathematically modeling a set of multidimensional surfaces corresponding to …

Transition From Laminar To Turbulent Flow Around An Airfoil, Chang-Ren Chen

Doctoral Dissertations

"A computational fluid dynamics (CFD) code has been developed for two-dimensional incompressible turbulent flows and employed to solve the Navier Stokes equations around an airfoil of arbitrary shape. A low-Reynolds-number k — e turbulence model including curvature effect was used to consider the gain and loss of turbulent kinetic energy. To include laminar sublayer into the computational domain, a multi-layer grid and a cubic-slpine grid were introduced through a conservative form of coordinate transformation. The flow structure varies with the Reynolds numbers. For an airfoil at low Reynolds numbers (below ten thousand), distinct vortex shedding patterns can be found in …

Particle Size And Velocity Measurements In Two Phase Flows Using Laser Doppler Velocimetry, Joseph Parker

Honors Theses

Laser Doppler Velocimetry is used in fluid mechanics to measure the velocity of particles in fluid flows. A small particle exhibits motion closely corresponding to the fluid behavior because of its ability to follow high frequency flow fluctuations. Large particles do not follow the flow field precisely but represent a second phase. This project used LDV to measure the size and velocity of particles in two phase flows by computer analysis of the Doppler signal.

Limiting Solar Radiation Effects On Outdoor Air Temperature Measurement, Florida Solar Energy Center, Robin Vieira

FSEC Energy Research Center®

This experimental study compares various methods of reducing the effects of solar radiation on outdoor air temperature measurements. It indicates that radiation effects can introduce significant measurement error, even with the use of shielding devices and aspiration, and outlines efforts that were taken to lessen the error caused by radiation.

Two separate tests were conducted, one comparing naturally ventilated and fan-aspirated radiation shields, the other comparing seven identical fan-aspirated shields. Results from the first test showed that one of the naturally ventilated shields was generally more effective than a fan- aspirated unit-at some instances of high radiation giving daytime temperatures …

Explicit Multistage Schemes For The Solution Of The Three-Dimensional Compressible Euler/Navier-Stokes Equations, Alaa Ahmed Elmiligui

Mechanical & Aerospace Engineering Theses & Dissertations

The objective of this study was to develop a high-resolution-explicit-multi-block numerical algorithm, suitable for efficient computation of the three-dimensional, time-dependent Euler and Navier-Stokes equations. The resulting algorithm has employed a finite volume approach, using MUSCL-type differencing to obtain state variables at cell interface. Variable interpolations were written in the $\kappa$-scheme formulation. Inviscid fluxes were calculated via Roe's flux-difference splitting, and van Leer's flux-vector splitting techniques, which are considered state of the art. The viscous terms were discretized using a second-order, central-difference operator.

Two classes of explicit time integration has been investigated for solving the compressible inviscid/viscous flow problems--two-stage predictor-corrector schemes, …

Design And Development Of An Automated Assembly System In A Discrete Manufacturing Environment, Sandeep K. Desai

Theses

This work is dedicated to extend the technology of automated assembly to include small and thin parts, light in weight. As the parts are thin a problem exists in the feeding process and orientation. The objective of project is to overcome this difficulty. The main theme of this thesis is to reduce labor cost and to improve productivity and quality of assembly operations by introducing low cost automation in the companies having discrete manufacturing environment.

An example of assembly involving a thin part has been selected. Two components from an electrical switch assembly are chosen, namely the spring and rivet. …

Handling Of Glass Mat Thermoplastic From Manufacturing Station To Heating Station To Molding Machine, Ramulu Srinivas Neela

Theses

GMT composite sheets are a family of continuous glass fiber roving impregnated with thermoplastic resin with parts formed by compression molding. Significance of GMT sheets comes by its cost-effective performance sufficient to penetrate automotive, industrial, construction, and other markets not willing to pay for higher cost, fiber-reinforced composite systems. GMTs in comparison to traditional sheet metals and sheet molding compounds (SMCs) are lighter, corrosion resistant, require no special storage, exhibit faster cycle times, require no chemical reaction, produce less scrap, possess recycling benefits, are ready for painting, and exhibit maximum opportunities for parts consolidation due to exceptional strength, formability, lower …

Study Of A Non-Contact Gaging System Of Inspection, Gordhanbhai Ketan Patel

Theses

The quality control function has traditionally been performed using manual inspection methods and statistical sampling procedures. Manual inspection is generally a time - consuming procedure which involves precise, yet monotonous work. It often requires that parts be removed from the vicinity of the production machines to a separate inspection area. This causes delays and often constitutes a bottleneck in the manufacturing schedule.

As a solution to the above problem a Non - Contact Gaging System developed by Optical Gaging Products, Inc., has been used here to study the feasibility of using an automated inspection system and a procedure of developing …

A Graphic Editor And Real Time Simulator Of Petri Net, Tenian Tang

Theses

A structurally designed graphic editor and real time simulator of Petri nets (PN) is presented. The package is programmed by Turbo C language, which runs in IBM-PC environmental with graphics adaptor. Various kinds of PN systems such as ordinary, general and timed Petri net can be modeled and analyzed by firing the models with real time token movement animations. Some properties of analyzed PN such as reachability, deadlock, firing time can be studied. Several illustrative examples are presented. The possible further enhancements are also discussed.

Development Of An Expert System For The Safety Of Workers From Electrical Hazards At Work Place, Faizul Islam

Theses

This thesis presents the development of an expert system for the safety of workers from electrical hazards at work place.

The objective of this work is to show how an expert system within the workplace can be used in helping to create an effective safety program.

An effective expert system for electrical safety have been developed for the workers to prevent accidents from electrical hazards using the safety regulations of Occupational Safety and Health Administration.

The regulations developed by OSHA have been incorporated in rule based expert system which can be accessed by any non computer professional and the system …

Computer-Aided Process Planning (Capp) Sorich, Sohail Pirzada

Theses

The last two decades have witnessed the increasing role of the computer in the process planning function. This has been further enhanced by the advent of the knowledge based expert system, and its impact on Computer Aided Process Planning (CAPP). CAPP has emerged as a strategic link between design and manufacture. This thesis discusses the various methods used in the process planning function. Group Technology (GT) plays a pivotal role in establishing CAPP. The utilization of Artificial Intelligence techniques in CAPP is listed. This study also presents an Interactive Software adaptive to product/part configuration variables.

Redesign Of Parts And Simulation Of Flexible Assembly Cell For Safety Water Shower Assembly, Balraj Y. Gardilla

Theses

A Design for Assembly (DSA) method is used to analyze the safety water shower assembly and to redesign the components with emphasis on meeting the criteria of allowing for flexible Assembly Cell (FAS). An Expert System is developed to select the right Assembly using VP-Expert. This thesis contrasts the old and new safety water shower assembly designs and describes the design of a final Flexible Assembly Cell. A PUMA 550 robot was investigated for use in the cell design. The flexible Assembly cell is simulated on silicon graphics using the IGRIP software. The economics of each part presentation method is …

A Case Study On Petri Net Modeling, Animation, And Simulation, Suresh C. Gurala

Theses

Petri nets as a graphical tool has developed over the last decade into a suitable model for representing, modeling, designing, analyzing and studying concurrent systems. In this thesis, Petri nets are applied for analyzing, modeling and simulation of a flexible assembly station. An existing AT&T FWS200 flexible assembly workstation for printed circuit board is modeled using Petri nets without the consideration of insertion failures and other abnormalities in the system. The Petri net model is then simulated using Graphics simulation language (GSL).

Advanced Manufacturing Applications Of Cost Estimating Techniques For Metal Cutting Industries, Zubair Hamid

Theses

In this work, different cost estimating techniques in metal cutting industry were studied. A basic understanding of estimation concepts were given. The typical breakdown of total cost was also given and discussed in details. Practical applications of cost estimating is studied. The effect of different parameters which relate to the lot sizes or quantity were discussed. All these results show that total cost is minimum at a point which is called least cost point, after that cost increases because of the addition of extra resources, in terms of man, machine and increase in administrative expenses.

Development Of Cellular Manufacturing Systems For Overall Production Efficiency, Srinivas Lokula

Theses

For years the industrial job shop is facing an increase in complexity and decline in productivity due to increase in parts mix, volume of parts, plant size, machine production rates and part complexity. The development of Group Technology and Cellular Manufacturing seeks to eliminate or minimize complexity and to maximize productivity.

Cellular manufacturing is the physical division of job shop's manufacturing machinery into production cells. Each cell is designed to produce parts requiring similar machinery and machine operations. Cellular manufacturing is one of the best manufacturing techniques to support Just In Time manufacturing and Total Quality Management.

This thesis work …

Design For Manufacturability (Computer Aided Optimum Gear Design), Narayan R. Mareddy

Theses

Design for manufacturing has design as the first manufacturing step. It is important to recognize the importance of design clubing with manufacturing to reduce the production, set up time. In this thesis concepts of design, manufacturing and four different ways of bringing design and manufacturing together are discussed in detail.

As there are large number of variables in the gear rating equations, it is very difficult to achieve optimum design by manual methods unless an extensive trial and error process is carried out. An algorithm has been developed which allows rapid convergence to the optimum gear design. The algorithm has …

Implementing Computer Numerical Control Machine Tools In A Job Shop Environment, Rajesh Shah

Theses

Computer Numerical Control is one important phase to overall application of computer on the shopfloor. Today a large variety of CNC machine tools are offered by manufacturer following different standards. This thesis is organized with the purpose of comparing various technical and economical considerations for CNC machine tool purchase and application. The main purpose of study is to mention various features of CNC machine tools and its possible integration which can reduce product lead time and improve quality. General replacement minimum cost model is discussed with case study for economic justification of machine purchase. While discussing technical features emphasis is …

Unsteady Flow In Vertical, Converging Tubes, Hamid Johari, William W. Durgin

Office of the Provost Scholarship

The discharge of liquids from vertical tubes with various contraction geometries was studied via the unsteady Bernoulli equation. The temporal variations of the exit velocity and fluid level in the tube were found from the numerical integration of nonlinear differential equations. Sudden, quadratic, and exponential contraction geometries were considered. For inlet to exit area ratios greater than two, the flow initially accelerates to a maximum speed and then it decelerates for the geometries studied. The exponential contraction has the shortest discharge time. The solutions also reveal that the largest possible velocity and the shortest discharge time are achieved in a …

Evolution And Impact Of Changes Of Technological Development In Some Of The French Manufacturing Organizations, T S Nagabhushana

IIMB Management Review

No abstract provided.

Equipment Acquisition Lcc Approach, B S Chetty, K N Krishnaswamy

IIMB Management Review

The Life Cycle Costing (LCC) approach focuses attention on all funds to be expended during the useful life of a productive asset including associated activities directly linked to its use. LCC improves upon the procedure/evaluation criterion which is today totally biased towards short-term approach such as considering only first cost or price alone. The obvious benefits of the approach are discussed in detail in this paper for adaptation by organisations. However, the need for approriate data for applying this approach is also emphasised.

Test 1656: Ford 5640 (16x4) Diesel 16-Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

EXPLANATION OF THE TEST PROCEDURE General Tractors are tested at the University of Nebraska according to the Agricultural Tractor Test Code approved by the American Society of Agricultural Engineers and the Society of Automotive Engineers or official Nebraska test procedure. The manufacturer selects the tractor to be tested and certifies that it is a stock model. Each tractor is equipped with the common power consuming accessories such as power steering, power lift pump, generator, etc., if available. Power consuming accessories may be disconnected only when the means for disconnecting can be reached from the operating station. An official representative of …