Engineering Commons^™

Automating Tolerance Synthesis: A Framework And Tools, Stephen C.-Y. Lu, Robert G. Wilhelm

Department of Mechanical and Materials Engineering: Faculty Publications

This paper describes CASCADE-T—a new approach to tolerance synthesis that uses a complete representation of the conditional tolerance relations that exist between features of a part under design. Conditional tolerances are automatically determined from functional requirements and shape information. Tolerance primitives based on the virtual boundary requirements approach to tolerance representation are composed to form more complex tolerance relationships. Artificial intelligence techniques, including a constraint network, frame-based system, and dependency tracking are used to support flexible and detailed computation for tolerance analysis and synthesis.

Nondestructive Detection Of An Undeserable Metallic Phase, T1, During Processing Of Alumnum-L Thumalloys, Otto Buck, David J. Bracci, David C. Jiles, Lisa J.H. Brasche, Jeffrey E. Shield, Leonard S. Chumbley

Department of Mechanical and Materials Engineering: Faculty Publications

A method is disclosed for detecting the T1 phase in aluminum-lithium alloys through simultaneous measurement of conductivity and hardness. In employing eddy current to measure conductivity, when the eddy current decreases with aging of the alloy, while the hardness of the material continues to increase, the presence of the T1 phase may be detected.

Ultrasonic Nondestructive Evaluation Of Fibre-Reinforced Composite Materials - A Review, Vikram K. Kinra, Vinay Dayal

Vinay Dayal

This paper reviews various ultrasonic nondestructive evaluation techniques applicable to fibre-reinforced composites. The techniques are briefly described and key references are cited. Methods to evaluate the reduced stiffness of composites due to micro-damage are described. Results show that for composites through-the-thickness attenuation increases and stiffness does not change due to transverse cracks, but in-plane stiffness and attenuation changes are substantial and can be measured by the Lamb wave techniques.

Microcomputer Based Digital Image Processing System Developed To Count And Size Laser-Generated Small Particle Images, K. D. Ahlers, D. R. Alexander

Department of Mechanical and Materials Engineering: Faculty Publications

A microcomputer-based digital image processing system has been developed to count and size laser-generated small particle images. Processing rates of 5 to 600 frames per minute were achieved by utilizing a real-time digital image processor. Particles from 7 to 700 µm in the plane of focus were counted and sized. A major emphasis in this work was to determine the basic problems and limitations involved with using a digital image processing scheme to accurately size particles. Areas that were investigated include the effect of the threshold level on measured particle size, particle boundary diffraction gray-level gradients, and geometric nonlinearities introduced …

An Experimental And Analytical Investigation Of The Iosipescu Shear Test For Composite Materials, Barry Stuart Spigel

Mechanical & Aerospace Engineering Theses & Dissertations

Mechanical properties of composite materials under shear loading are difficult to determine. The Iosipescu Shear test, originally proposed for metals, has in recent years been applied to composites. It has the advantages of small specimen size, simple loading and a reasonably uniform shear stress in the test section.

The purpose of this work is to study the validity of the Iosipescu test method for measuring the shear modulus and shear strength of composites. Finite element analyses indicate that optimum specimen geometry and load locations depend upon the degree of orthotropy of the composite. Test results for a quasi-isotropic graphite/epoxy laminate …

Low Cost Fencing, Department Of Agriculture, Western Australia

Journal of the Department of Agriculture, Western Australia, Series 4

Fences with more wire and posts are not necessarily stronger.

Design using high tensile wire can save on materials and reduce costs.

Studies Of Bistable Fluid Devices For Particle Flow Control, Gerald H. Hogland

Dissertations and Theses

This study was directed toward the development of a bistable wall attachment Flip-Flop device which was capable of directionally controlling particle flow. The particles were transported by a fluid stream which under the influence of wall attachment. The dominant criteria in the development of the device was the achievement of the highest recovery of particles at the active output, without destroying the wall attachment of the fluid stream The experiment was conducted in several distinct stages; each of which was concerned with at least one aspect of wa1l attachment or particle flow. Results derived from one test were used to …

Comparative Study Of Lightweight And Normal Weight Concrete In Flexure, Mohammad Zareh

Dissertations and Theses

This investigation represents a comparative study of the flexural behavior of lightweight and normal weight concrete. Both theoretical and experimental moment-curvature characteristics of the tested specimens were used to study the flexural behavior.

A generalized computer program to determine the moment-curvature relationships of a singly reinforced rectangular concrete beam was developed.

For this limited study it was observed that lightweight concrete beams when compared to normal concrete beams achieve comparable moment capacity (about 92% of normal weight concrete) but exhibit higher deflections (about 40% more than normal weight concrete).

Concrete In Dairies, D Roger Buchanan

Journal of the Department of Agriculture, Western Australia, Series 4

PRIME requirements for exposed concrete surfaces in dairies are that they should be easily cleansed and should not deteriorate in contact with milk and milk products.

In milking stalls, animal races and on loading platforms hardwearing surfaces which offer good foothold are also necessary.

Controlled Environment Broiler Houses In Western Australia, D F. Hessels

Journal of the Department of Agriculture, Western Australia, Series 4

The three main features which contribute to the better returns from controlled environment broiler housing are higher density, better conversion and a reduction in labour.

The higher initial cost of housing and higher running costs are more than covered by these three advantages.

Siphon Tubes For Furrow Irrigation In The Kimberleys, K S. Cole

Journal of the Department of Agriculture, Western Australia, Series 4

Irrigation soils in the Ord River area have a high clay content and erode easily under the influence of running water.

To overcome the problem of erosion in cuts between the head channels and irrigation furrows polythene siphon tubes have been found the most satisfactory.

In this article K. S. Cole, B.Sc. (Agric), Agricultural Adviser, Kununurra, describes the use of siphon tubes for furrow irrigation in the Kimberleys.

Blasting. Part 2. Explosives On The Farm, G A. Greaves

Journal of the Department of Agriculture, Western Australia, Series 4

EXPLOSIVES will function with maximum reliability and efficiency only when they are carefully stored under cool, dry conditions so as to avoid deterioration.

When preparing charges the user should follow a correct procedure and use the proper tools. Always treat explosives with respect and remember they are made to explode. When they hit they hit hard.

Its Shearing Time, Department Of Agriculture, Western Australia

Journal of the Department of Agriculture, Western Australia, Series 4

SHEARING will soon be taking place on your property. For a smooth annual wool harvest, remember:—

Plan For Quality In Silage, Department Of Agriculture, Western Australia

Journal of the Department of Agriculture, Western Australia, Series 4

SILAGE making time is fast approaching in the South-West.

Last minute preparations before harvesting will help avoid delays at the time of making this valuable fodder, thereby reducing the amount of costly spoilage caused by hold-ups.

Blasting. Part 1. Explosives And The Farmer, G A. Greaves

Journal of the Department of Agriculture, Western Australia, Series 4

ABOUT 3,000 tons of commercial blasting explosives of various types are used every year in Western Australia of which approximately two thirds is utilised by mining industries and the remainder goes mainly to quarrying and public works.

The farmer and orchardist actually use only very small amounts but nevertheless explosives are a very useful working tool for the primary producer.

Australian Spark Arrester Tests : Spark Arrester For International B-250, W. F. Baillie, G. H. Vasey

Journal of the Department of Agriculture, Western Australia, Series 4

FORMAL tests on spark arresters are conducted by The Tractor Testing Committee at the Testing Station, Werribee, on behalf of those companies concerned with tractors, engines or spark arresters who wish to have these equipments tested.

Australian Spark Arrester Tests : Spark Arrester For Fordson Dexta, W. F. Baillie, G. H. Vasey

Journal of the Department of Agriculture, Western Australia, Series 4

FORMAL tests on spark arresters are conducted by The Tractor Testing Committee at the Testing Station, Werribee, on behalf of those Companies concerned with tractors, engines or spark arresters who wish to have these equipments tested.

The arrester is tested on the engine for which it is especially designed or if this is not convenient, it is tested on an engine having the characteristics and power for which the spark arrester is intended.

Jackscrews, Albert Lewis Kenyon

Student and Lippitt Prize essays

Definition, development, and description of the jackscrew, a device for the application of the screw to the moving of heavy weights.