This volume contains the edited version of lectures and selected research contributions presented at the NATO ADVANCED STUDY INSTITUTE on MECHANICAL BEHA VI OUR OF MATERIALS AT HIGH TEMPERATURE, held in Sesimbra, Portugal, 12th-22nd September 1995, and organized by 1ST-Lisbon Institute of Technology, PortugaL The Institute was attended by 88 participants, including 15 lecturers from 17 countries including five CP countries. The lecturers were leading scientists and technologists from universities, research institutions and industry. The students were mainly young PhD students and junior academic or research staff with postgraduate qualifications (MSc or PhD). Fourteen students were from the five CP countries. The students presented research papers or posters during the Institute reporting the current progress of their research projects. A total of thirty three lectures, ten research papers and fifty posters were presented. This book does not contain the poster presentations and seven research papers were selected for publication. All the sessions were very active and quite extensive discussions on scientific aspects took place during the Institute. The Advanced Study Institute provided a forum for interaction among scientists and engineers from different areas of research, and young researchers.

The International Conference on Fracture Mechanics in Engineering Applica tion convened at the r ational Aeronautical Laboratory (NAL) in Bangalore, India, March 26-30, 1979, with the presence of approximately 400 scientists and engi neers. The participants included individuals from all parts of India, United States of America, United Kingdom, Japan, Holland, France, Hong Kong, Korea, Sweden and Poland. The Conference was organized jointly by NAL, Bangalore;and Lehigh University, USA. Various organizations in India have also supported the Conference most generously. Professor S. Dhawan, Director of the Indian Institute of Science and Secre tary of Department of Space, delivered the inaugural speech. He said that the advance of science was the precondition of the development and survival of human society in the modern world. "It is true that in recent times, science and tech nology - and their practitioners - have been subjected to much public scrutiny, debate and severe criticism." On the other hand, the depletion of non-renewable resources, degradation of the natural environment and a host of other problems had been laid at the door of technology and science. One cannot deny that funda mental advances in the physics and chemistry of the structure of matter had led to spectacular engineering progress. Advanced technologies like nuclear energy and space exploration were but expression of the central role of computors, elec tronics, optics, polymers, etc., and all of these were heavily dependent on the successful application of material science and technology."

The IUTAM Symposium on "Combustion in Supersonic Flows" was held in Poitiers at Ecole Nationale Superieure de Mecanique et d'Aerotechnique (ENSMA) from 2 to 6 october 1995. The Symposium was hosted by the Laboratoire de Combustion et de Detonique (UPR - CNRS 9028) and was attended by 60 delegates from 10 countries. The formal presentations and invited lectures were focused on four main topics, related to combustion in supersonic streams and practical issues relative to the development of new propulsion system: fundamental studies on premixed and unpremixed combustion, fluid dynamic aspects of supersonic combustion, practical system including Scramjet, Ramaccelerators and Pulsed Detonation Engines, application of detonation to propulsion. Invited lectures presenting the state of the art on these topics as well as available data base were delivered by professors Paul A. Libby from University of California at San Diego, Vladimir Sabel'nikov from TsAGI (Russia), Paul Clavin from IRPHE (Marseille, France) and Drs Shmuel Eidelman from SAlC (USA), Gunter Smeets from the French-German Institut of Saint-Louis and Bruno Deshaies from LCD (poi tiers, France).

Petroleum engineers continue to need cost saving and environmentally sustainable products and methods for today's hydraulic fracturing operations. Hydraulic Fracturing Chemicals and Fluid Technology, Second Edition, continues to deliver an easy-to-use manual of fluid formulations to meet specific job needs. Enhanced with more environmental aspects, this reference helps engineers and fluid specialists select and use the appropriate chemicals for any hydraulic fracturing job. New information concerning nanotechnology applications such as wellbore sealant and proppants are added to enhance operations in a sustainable manner while saving on production costs. Other updates include low recovery of fracturing water in shale, surfactants for waterless hydraulic fracturing, and expanded produced water treatment. Rounding out with updated references and patents for easy reference, Hydraulic Fracturing Chemicals and Fluid Technology, Second Edition, gives engineers a critical guide on selecting better products to boost productions while strengthening environmental enhancement and consideration.

This book provides a simple and unified approach to the mechanics of discontinuous-fibre reinforced composites, and introduces readers as generally as possible to the key concepts regarding the mechanics of elastic stress transfer, intermediate modes of stress transfer, plastic stress transfer, fibre pull-out, fibre fragmentation and matrix rupture. These concepts are subsequently applied to progressive stages of the loading process, through to the composite fractures. The book offers a valuable guide for advanced undergraduate and graduate students attending lecture courses on fibre composites. It is also intended for beginning researchers who wish to develop deeper insights into how discontinuous fibre provides reinforcement to composites, and for engineers, particularly those who wish to apply the concepts presented here to design and develop discontinuous-fibre reinforced composites.

1) Presents a new type of S-N equation 2) Discusses empirical fracture equations of mixed mode crack 3) Applies the Wohler Curve Methods for a Low/Medium/High cycle fatigue in metallic materials 4) Enables the reader to analyse failure and fracture in metallic materials

Dislocation Based Crystal Plasticity: Theory and Computation at Micron and Submicron Scale provides a comprehensive introduction to the continuum and discreteness dislocation mechanism-based theories and computational methods of crystal plasticity at the micron and submicron scale. Sections cover the fundamental concept of conventional crystal plasticity theory at the macro-scale without size effect, strain gradient crystal plasticity theory based on Taylar law dislocation, mechanism at the mesoscale, phase-field theory of crystal plasticity, computation at the submicron scale, including single crystal plasticity theory, and the discrete-continuous model of crystal plasticity with three-dimensional discrete dislocation dynamics coupling finite element method (DDD-FEM). Three kinds of plastic deformation mechanisms for submicron pillars are systematically presented. Further sections discuss dislocation nucleation and starvation at high strain rate and temperature effect for dislocation annihilation mechanism.

1. Uses practical industry examples to illustrate key concepts of mechanics and stress analysis 2. Includes worked examples and MATHCAD programs 3. Presents the theory behind stress analysis with reference to multiple disciplines, making this a comprehensive book 4. Covers composite material stress analysis, plate analysis and Finite Element Method

This book demonstrates fatigue crack growth under random loading graphically. This state-of-the-art monograph introduces an expert system for crack growth predictions, particularly based on crack closure. The system is developed after years of research by the authors by using the Math-type software consisting of 5 parts. This system is unique as it is fundamentally different from previous systems as it focuses on fatigue crack growth predictions based on fatigue crack closure. This book can be a useful guide for practicing engineers, researchers, and students in the fields of mechanical, aerospace, or civil engineering.

1) Includes a chapter on early theories on fracture as well as modern understandings 2) Contains a chapter on fatigue crack and creep fatigue crack 3) Provides an in-depth discussion of both linear elastic and nonlinear fracture mechanics 4) Includes both solved and unsolved example problems and end of chapter problems, and instructor support materials are also available

Modern fracture mechanics considers phenomena at many levels, macro and micro; it is therefore inextricably linked to methods of theoretical and mathematical physics. This book introduces these sophisticated methods in a straightforward manner. The methods are applied to several important phenomena of solid state physics which impinge on fracture mechanics: adhesion, defect nucleation and growth, dislocation emission, sintering, the electron beam effect and fractal cracks. The book shows how the mathematical models for such processes may be set up, and how the equations so formulated may be solved and interpreted. The many open problems which are encountered will provide topics for MSc and PhD theses in fracture mechanics, and in theoretical and experimental physics. As a supplementary text, the book can be used in graduate level courses on fracture mechanics, solid matter physics, and mechanics of solids, or in a special course on the application of fracture mechanics methods in solid matter physics.

This textbook covers the collision of a moving, falling or flying object on a rigid barrier or a structural element, and the transmission of the transient action to the rest of the structural system. It is the only up-to-date book on this under-researched topic that confronts engineers on a day-to-day basis. The book deals with a range of real-life engineering problems and focuses on the application of knowledge and skillsets from structural analysis and structural dynamics. Fundamental principles and concepts on structural collision are first introduced, followed by their specific applications such as vehicular collision on bridge structures, boulder impact on rockfall barriers and collision by hail and windborne debris. Analytical solutions provided are in the form of closed-form expressions, which can be directly adopted in conventional manual calculations. The use of spreadsheets to simulate the dynamic response behaviour is also covered. The only standalone book covering the topic from a civil engineering perspective Practical guidance on real-life engineering problems, and use of computational and physical methods Conveys methodology validated experimentally The book provides an excellent guide for practitioners and sets out fundamental principles for graduate students in civil, structural and mechanical engineering.

- self-contained and well illustrated - complete and comprehensive derivation of mechanical/mathematical results with enphasis on issues of practical importance - combines classical subjects of fracture mechanics with modern topics such as microheterogeneous materials, piezoelectric materials, thin films, damage - mechanically and mathematically clear and complete derivations of results

Rock Fracture and Blasting: Theory and Applications provides the latest on stress waves, shock waves, and rock fracture, all necessary components that must be critically analyzed to maximize results in rock blasting. The positioning of charges and their capacity and sequencing are covered in this book, and must be carefully modeled to minimize impact in the surrounding environment. Through an explanation of these topics, author Professor Zhang's experience in the field, and his theoretical knowledge, users will find a thorough guide that is not only up-to-date, but complete with a unique perspective on the field.

This book is about the use of fracture mechanics for the solution of practical problems; academic rigor is not at issue and dealt with only in as far as it improves insight and understanding; it often concerns secondary errors in engineering. Knowledge of (ignorance of) such basic input as loads and stresses in practical cases may cause errors far overshadowing those introduced by shortcomings of fracture mechanics and necessary approximations; this is amply demonstrated in the text. I have presented more than three dozen 40-hour courses on fracture mechanics and damage tolerance analysis, so that I have probably more experience in teaching the subject than anyone else. I learned more than the students, and became cognizant of difficulties and of the real concerns in applications. In particular I found, how a subject should be explained to appeal to the practicing engineer to demonstrate that his practical problem can indeed be solved with engineering methods. This experience is reflected in the presenta tions in this book. Sufficient background is provided for an understanding of the issues, but pragamatism prevails. Mathematics cannot be avoided, but they are presented in a way that appeals to insight and intuition, in lieu of formal derivations which would show but the mathematical skill of the writer."

This book applies vibration engineering to turbomachinery, covering installation, maintenance and operation. With a practical approach based on clear theoretical principles and formulas, the book is an essential how-to guide for all professional engineers dealing with vibration issues within turbomachinery. Vibration problems in turbines, large fans, blowers, and other rotating machines are common issues within turbomachinery. Applicable to industries such as oil and gas mining, cement, pharmaceutical and naval engineering, the ability to predict vibration based on frequency spectrum patterns is essential for many professional engineers. In this book, the theory behind vibration is clearly detailed, providing an easy to follow methodology through which to calculate vibration propagation. Describing lateral and torsional vibration and how this impacts turbine shaft integrity, the book uses mechanics of materials theory and formulas alongside the matrix method to provide clear solutions to vibration problems. Additionally, it describes how to carry out a risk assessment of vibration fatigue. Other topics covered include vibration control techniques, the design of passive and active absorbers and rigid, non-rigid and Z foundations. The book will be of interest to professionals working with turbomachinery, naval engineering corps and those working on ISO standards 10816 and 13374. It will also aid mechanical engineering students working on vibration and machine design.

Presents a new physical and mathematical theory of irreversible deformations and ductile fracture of metals that acknowledges the continuous change in the structure of materials during deformation and the accumulation of deformation damage. Plastic deformation, viscous destruction, evolution of structure, creep processes, and long-term strength of metals and stress relaxation are described in the framework of a unified approach and model. The author then expands this into a mathematical model for determining the mechanical characteristics of quasi-samples of standard mechanical properties in deformed semi-finished products.

Many approaches have been proposed to solve the problem of finding the optic flow field of an image sequence. Three major classes of optic flow computation techniques can discriminated (see for a good overview Beauchemin and Barron IBeauchemin19951): gradient based (or differential) methods; phase based (or frequency domain) methods; correlation based (or area) methods; feature point (or sparse data) tracking methods; In this chapter we compute the optic flow as a dense optic flow field with a multi scale differential method. The method, originally proposed by Florack and Nielsen [Florack1998a] is known as the Multiscale Optic Flow Constrain Equation (MOFCE). This is a scale space version of the well known computer vision implementation of the optic flow constraint equation, as originally proposed by Horn and Schunck [Horn1981]. This scale space variation, as usual, consists of the introduction of the aperture of the observation in the process. The application to stereo has been described by Maas et al. [Maas 1995a, Maas 1996a]. Of course, difficulties arise when structure emerges or disappears, such as with occlusion, cloud formation etc. Then knowledge is needed about the processes and objects involved. In this chapter we focus on the scale space approach to the local measurement of optic flow, as we may expect the visual front end to do. 17. 2 Motion detection with pairs of receptive fields As a biologically motivated start, we begin with discussing some neurophysiological findings in the visual system with respect to motion detection.

The request to organize under its patronage at Poitiers in 1998 a Symposium entitled "Advanced Optical Methods and Applications in Solid Mechanics" by the International Union of Theoretical and Applied Mechanics (I.U.T.A.M.) was well received for the following two reasons. First, for nearly 20 years no Symposium devoted to optical methods in solids had been organized. Second, recent advances in digital image processing provided many new applications which are described in the following. We have the honour to present here the proceedings of this Symposium. st th The Symposium took place from august 31 to September 4 at the Institut International de la Prospective in Futuroscope near Poitiers. A significant number of internationally renowned specialists had expressed their wish to participate in this meeting. The Scientific Committee proposed 16 general conferences and selected 33 regular lectures and 17 poster presentations. Papers corresponding to posters are not differentiated in the proceedings from those that were presented orally. It is worth noting that a total of 80 participants, representing 16 countries, registered for this symposium.. The Scientific Committee deserves praise for attracting a significant number of young scientists, both as authors and as participants. Let us add our warm acknowledgements to Professor J.W. Dally and to Professor A.S. Kobayashi who, throughout the symposium preparation time, brought us valuable help.

It is difficult to do justice to fracture mechanics in a textbook, for the subject encompasses so many disciplines. A general survey of the field would serve no purpose other than give a collection of references. The present book by Professor E. E. Gdoutos is refreshing because it does not fall into the esoteric tradition of outlining equations and results. Basic ideas and underlying principles are clearly explained as to how they are used in application. The presentations are concise and each topic can be understood by advanced undergraduates in material science and continuum mechanics. The book is highly recommended not only as a text in fracture mechanics but also as a reference to those interested in the general aspects of failure analysis. In addition to providing an in-depth review of the analytical methods for evaluating the fundamental quantities used in linear elastic fracture mechanics, various criteria are discussed re: O. ecting their limitations and applications. Par ticular emphases are given to predicting crack initiation, subcritical growth and the onset of rapid fracture from a single criterion. Those models in which it is assumed that the crack extends from tip to tip rely on the specific surface energy concept. The differences in the global and energy states before and after crack extension were associated with the energy required to create a unit area of crack surface. Applications were limited by the requirement of self-similar crack growth."

Within the last thirty years there is a growing acknowledgement that prevention of catastrophic failures necessitates engagement of a large pool of expertise. Herein it is not excessive to seek advice from disciplines like materials science, structural engineering, mathematics, physics, reliability engineering and even economics. Today's engineering goals, independently of size; do not have the luxury of being outsideaglobalperspective.Survivaloftheintegratedmarketsand?nancialsystems require a web of safe transportation, energy production and product manufacturing. It is perhaps the ?rst decade in engineering history that multidisciplinary - proaching is not just an idea that needs to materialise but has matured beyond infancy. We can witness such transition by examining engineering job descriptions and postgraduate curricula. The undertaking of organising a conference to re?ect the above was not easy and de?nitely, not something that was brought to life without a lot of work and c- st mitment. The 1 Conference of Engineering Against Fracture from its conceptual day until completion was designed in a way of underlying the need of bringing all the key players on a common ground that once properly cultivated can ?ourish. To achieve that the conference themes were numerous and despite their, in principle notional differences, it was apparent that the attendees established such common ground through argumentation. The reader can see this from the variety of research areas re?ected by the works and keynote lecturers presented.

The updated and improved second edition of Direct Gear Design details a nonstandard gear design approach that makes it possible to significantly improve gear drive performance. Providing engineers with gear design solutions beyond standard limits, this book delivers engineers with practical and innovative solutions to optimize gearing technologies. The majority of modern gears are over-standardized, not allowing gear design engineers to see possible gear design solutions outside of standard limits. The book explores opportunities to improve and optimize gears beyond these limitations. The method of Direct Gear Design has been proven to maximise gear drive performance, increase transmission load capacity and efficiency, and reduce size and weight. Discussing the use of gears made from powder metal and plastic, the book surveys gear manufacture and makes use of extensive references to encourage further exploration of gear design innovation. Additionally, the book provides an overview of manufacturing technologies and traditional gear design, as well as covering topics such as asymmetric gears, tolerance selection and measurement methods of custom gears. Written accessibly, with a focus on practical examples, this fully updated edition will serve as a guidebook for all professionals exploring high-performance gearing system technologies.

In this volume various integral equations for multiple crack problems in plane elasticity are investigated. Formulation of the problems is based on relevant elementary solutions in which the complex variable function method is used. The multiple crack problem is considered as a superposition of many single crack problems while many more complicated cases, including bonded dissimilar materials and multiple thermally insulated crack problems, are considered. Miscellaneous problems, including the multiple rigid line problem and the multiple circular hole problem are studied. Solutions for three-dimensional multiple crack problems are also investigated by using the Fredholm integral equation, the hypersingular integral equation and the variational principle. Many programs for multiple crack problems using FORTRAN are featured. A CD-ROM containing solutions is also included.

Material technology has become so diversified in theories and the construction of novel microstructures that the researchers and practitioners are drifting further apart. This book is based on material presented at an International Symposium in Xanthi, Greece in July 1989. The symposium attracted a group of individual engineers and scientists from the East and West who tackled the question of why particular manipulations of a given material have particular effects. Emphasis is laid on the strain energy function because of the versatile role it plays in mechanics and physics. It has been used successfully not only in predicting the failure of solids but also in formulating constitutive relations in continuum mechanics. The material presented falls within the areas of: Fundamentals of Strain Energy Density, Damage Analysis on Strain Energy Density, Strain Energy Density as Failure Criterion, Applications, and Composites.