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The development of the high‐pressure expansive engine represented a watershed in the evolution of steam power technology, allowing the attainment of major fuel economies. In Britain, Cornish engineers took the lead in the exploration of this specific technological trajectory. Notwithstanding its superior fuel efficiency was immediately widely discussed, the high‐pressure expansive engine did not find widespread application in other steam‐using regions (in particular in Lancashire), where the Watt low‐pressure engine continued to be the favourite option. This article provides a reassessment of the factors accounting for the precocious adoption of the high‐pressure steam engine in Cornwall and for its delayed fortune in the rest of Britain.

The five chapters of this volume treat topics of current significance, demonstrating how essential electrochemisty is for technological progress. W.P. Gomes and H.H. Goosens analyze the kinetics of the electrochemical reactions used for etching gallium arsenide. The authors describe means by which information about the mechanisms may be obtained. Based on the understanding of the anodic dissolution of n-type and p-type GaAs, both in the dark and under illusmination, etching mechanisms for different oxydants with and without current are derived. H. Lehmkuhl, K. Mehler and U. Landau provide a summary of the criteria and problems associated with the electrodeposition of aluminium at ambient temperature. Special emphasis is given to the organo-aluminium electrolyte developed in the laboratory of Karl Ziegler, winner of the Nobel prize in 1963. Although difficult to handdle, these electrolytes offer sume unique advantages for the deposition of aluminium. Effects that cause non-uniformity in patterned electrodeposition of microscopic features are the subject of J.O. Dukovic's chapter. Mathematical models are used to identify process conditions which lead to flat profiled features of uniform height needed in electronic components. The emergence of computer-aided-design tools for electrochemical microfabrication is discussed. Y. Okinaka and T. Osaka descrive the fundamental aspects and technological applications of autocatalytic metal deposition processes. In view of that "electroless deposition" has found important applicaitons in the manufaccture of microelectronic devices, a review of the pertaining electochemical fundamentals should be useful. Following a concise revie of direct access storage devices, a treatise on the properties and electrochemistry of magnetically soft materials is provided by P.C. Andricacos and L.T. Pomankiw. The chapter is focused on the fundamentals of the magnetics and electrochemistry of Permalloy, a material which has similar importance in magnetic storage as has silicon in semiconductor devices

AbstractSystems engineering has been plagued by the problem of how to separate a system from its environment or context, in particular from its social context. We propose to include anything in the system that is necessary for performing its intended function and that may be the object of design. For certain engineering systems, such as civil aviation systems, this implies that human agents and social institutions have to be taken as integral parts of these systems. These 'socio‐technical' systems are of a hybrid nature because they are constituted by different kinds of elements, intentional and non‐intentional: social institutions, human agents and technical artefacts. This paper analyses two different roles that human agents, as elements of socio‐technical systems, may play with regard to technical artefacts. Furthermore, it discusses some conceptual problems concerning the modelling of socio‐technical systems that are due to the hybrid nature of these systems. Copyright © 2006 John Wiley & Sons, Ltd.

Preface -- Notation Frequently Used -- 1. Introduction -- I. Hilbert Space -- 2. Inner Product of Functions. Norm, Metric -- 3. The Space L2 -- 4. Convergence in the Space L2(G) (Convergence in the Mean). Complete Space. Separable Space -- 5. Orthogonal Systems in L2(G) -- 6. Hilbert Space -- 7. Some Remarks to the Preceding Chapters. Normed Space, Banach Space -- 8. Operators and Functionals, especially in Hilbert Spaces -- II. Variational Methods -- 9. Theorem on the Minimum of a Quadratic Functional and its Consequences -- 10. The Space HA -- 11. Existence of the Minimum of the Functional F in the Space HA. Generalized Solutions -- 12. The Method of Orthonormal Series. Example -- 13. The Ritz Method -- 14. The Galerkin Method -- 15. The Least Squares Method. The Courant Method -- 16. The Method of Steepest Descent. Example -- 17. Summary of Chapters 9 to 16 -- III. Application of Variational Methods to the Solution of Boundary Value Problems in Ordinary and Partial Differential Equations -- 18. The Friedrichs Inequality. The Poincaré Inequality -- 19. Boundary Value Problems in Ordinary Differential Equations -- 20. Problem of the Choice of a Base -- 21. Numerical Examples: Ordinary Differential Equations -- 22. Boundary Value Problems in Second Order Partial Differential Equations -- 23. The Biharmonic Operator. (Equations of Plates and Wall-beams.) -- 24. Operators of the Mathematical Theory of Elasticity -- 25. The Choice of a Base for Boundary Value Problems in Partial Differential Equations -- 26. Numerical Examples: Partial Differential Equations -- 27. Summary of Chapters 18 to 26 -- IV. Theory of Boundary Value Problems in Differential Equations Based on the Concept of a Weak Solution and on the Lax-Milgram Theorem -- 28. The Lebesgue Integral. Domains with the Lipschitz Boundary -- 29. The Space W2(k)(G) -- 30. Traces of Functions from the Space W2(k)(G). The Space W?2(k)(G). The Generalized Friedrichs and Poincaré Inequalities -- 31. Elliptic Differential Operators of Order 2k. Weak Solutions of Elliptic Equations -- 32. The Formulation of Boundary Value Problems -- 33. Existence of the Weak Solution of a Boundary Value Problem. V-ellipticity. The Lax-Milgram Theorem -- 34. Application of Direct Variational Methods to the Construction of an Approximation of the Weak Solution -- 35. The Neumann Problem for Equations of Order 2k (the Case when the Form ((v, u)) is not V-elliptic) -- 36. Summary and Some Comments to Chapters 28 to 35 -- V. The Eigenvalue Problem -- 37. Introduction -- 38. Completely Continuous Operators -- 39. The Eigenvalue Problem for Differential Operators -- 40. The Ritz Method in the Eigenvalue Problem -- 41. Numerical Examples -- VI. Some Special Methods. Regularity of the Weak solution -- 42. The Finite Element Method -- 43. The Method of Least Squares on the Boundary for the Biharmonic Equation (for the Problem of Wall-beams). The Trefftz Method of the Solution of the Dirichlet Problem for the Laplace Equation -- 44. The Method of Orthogonal Projections -- 45. Application of the Ritz Method to the Solution of Parabolic Boundary Value Problems -- 46. Regularity of the Weak Solution, Fulfilment of the Given Equation and of the Boundary Conditions in the Classical Sense. Existence of the Function w ? W2(k)(G) satisfying the Given Boundary Conditions -- 47. Concluding Remarks, Perspectives of the Presented Theory -- Table for the Construction of Most Current Functionals and of Systems of Ritz Equations -- References.