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A computational procedure is presented for the re‐analysis of large unsymmetric structural systems. The procedure is based on a novel partitioning strategy in which the responses of both the original and modified structures are approximated by linear combinations of symmetric and antisymmetric response vectors (or modes), each obtained by using a fraction of the degree of freedom of the finite element model of the structure. The other key elements of the procedure are: (a) lumping of the large number of design variables into a single tracing parameter; (b) operator splitting or restructuring of the governing finite element equations to delineate the symmetric and antisymmetric vectors constituting the responses of the original and modified structures; and (c) a stable and efficient iterative process for generating the response of the modified structure. The re‐analysis procedure is applied to linear static analysis of framed structures. Design modifications consisted of removing members resulting in topologically unsymmetric structures. The potential of the procedure on multiprocessor computers is discussed and its effectiveness is demonstrated by means of two numerical examples.

A computational procedure is presented for the efficient non‐linear dynamic analysis of quasi‐symmetric structures. The procedure is based on approximating the unsymmetric response vectors, at each time step, by a linear combination of symmetric and antisymmetric vectors, each obtained using approximately half the degrees of freedom of the original model. A mixed formulation is used with the fundamental unknowns consisting of the internal forces (stress resultants), generalized displacements and velocity components. The spatial discretization is done by using the finite element method, and the governing semi‐discrete finite element equations are cast in the form of first‐order non‐linear ordinary differential equations. The temporal integration is performed by using implicit multistep integration operators. The resulting non‐linear algebraic equations, at each time step, are solved by using iterative techniques. The three key elements of the proposed procedure are: (a) use of mixed finite element models with independent shape functions for the stress resultants, generalized displacements, and velocity components and with the stress resultants allowed to be discontinuous at interelement boundaries; (b) operator splitting, or restructuring of the governing discrete equations of the structure to delineate the contributions to the symmetric and antisymmetric vectors constituting the response; and (c) use of a two‐level iterative process (with nested iteration loops) to generate the symmetric and antisymmetric components of the response vectors at each time step. The top‐ and bottom‐level iterations (outer and inner iterative loops) are performed by using the Newton—Raphson and the preconditioned conjugate gradient (PCG) techniques, respectively. The effectiveness of the proposed strategy is demonstrated by means of a numerical example and the potential of the strategy for solving more complex non‐linear problems is discussed.

Error indicators are introduced as part of a simple computational procedure for improving the accuracy of the finite element solutions for plate and shell problems. The procedure is based on using an initial (coarse) grid and a refined (enriched) grid, and approximating the solution for the refined grid by a linear combination of a few global approximation vectors (or modes) which are generated by solving two uncoupled sets of equations in the coarse grid unknowns and the additional degrees of freedom of the refined grid. The global approximation vectors serve as error indicators since they provide quantitative pointwise information about the sensitivity of the different response quantities to the approximation used. The three key elements of the computational procedure are: (a) use of mixed finite element models with discontinuous stress resultants at the element interfaces; (b) operator splitting, or additive decomposition of the finite element arrays for the refined grid into the sum of the coarse grid arrays and correction terms (representing the refined grid contributions); and (c) application of a reduction method through successive use of the finite element method and the classical Bubnov—Galerkin technique. The finite element method is first used to generate a few global approximation vectors (or modes). Then the amplitudes of these modes are computed by using the Bubnov—Galerkin technique. The similarities between the proposed computational procedure and a preconditioned conjugate gradient (PCG) technique are identified and are exploited to generate from the PCG technique pointwise error indicators. The effectiveness of the proposed procedure is demonstrated by means of two numerical examples of an isotropic toroidal shell and a laminated anisotropic cylindrical panel.

A simple and efficient re‐analysis procedure is presented for large‐scale structural systems. The procedure is based on using a mixed formulation with the fundamental unknowns consisting of both stress and displacement parameters. The other key elements of the procedure are: (a) lumping of the large number of design variables into a single tracing parameter; (b) operator splitting or additive decomposition of the different arrays in the finite element equations of the modified structure into the corresponding arrays of the original structure plus correction terms; and (c) application of a reduction method through the successive use of the finite element method and the classical Bubnov‐Galerkin technique. The finite element method is first used to generate a few approximation vectors (or modes). Then the amplitudes of these modes are computed by using the Bubnov—Galerkin technique. The re‐analysis procedure is applied to the linear static and free vibration problems of plate and shell structures. Changes in both the sizing and shape (configuration) design variables are considered. The high accuracy of the proposed technique, for sizable changes in the design variables, is demonstrated by means of numerical examples of composite plates and shells.

A two‐step computational procedure is presented for reducing the size of the analysis model for an anisotropic symmetric structure to that of the corresponding orthotropic structure. The key elements of the procedure are: (a) decomposition of the stiffness matrix into the sum of an orthotropic and non‐orthotropic (anisotropic) parts; and (b) successive application of the finite element method and the classical Rayleigh—Ritz technique. The finite element method is first used to generate few global approximation vectors (or modes). Then the amplitudes of these modes are computed by using the Rayleigh—Ritz technique. The global approximation vectors are selected to be the solution corresponding to zero non‐orthotropic matrix and its various‐order derivatives with respect to an anisotropic tracing parameter (identifying the non‐orthotropic material coefficients). The size of the analysis model used in generating the global approximation vectors is identical to that of the corresponding orthotropic structure. The effectiveness of the proposed technique is demonstrated by means of numerical examples and its potential for solving other quasi‐symmetric problems is discussed.

Part II and last MECHETTI. Vienna FOUNDED in 1795 by Carlo Mechetti as a dealer; since 1807 in partnership with his nephew, Pietro; the publishing firm styled Carlo Mechetti & Neffe in 1809; after Carlo's death in 1811, Pietro became sole owner; he was succeeded in 1850 by his widow, Therese; c. 1855 the firm was taken over by A. Diabelli & co. (cp. Peter Cappi).

In 1990 we compiled an annotated bibliography of official state lists of endangered, threatened, and rare species. In gathering information for that bibliography, which appeared in Reference Services Review in Spring 1991, we found numerous unofficial sources of state lists, such as those developed by universities, institutes, and Natural Heritage Programs, which also provide valuable information on statuses of endangered, threatened, and rare species. A comprehensive search for unofficial lists results in this second bibliography.

Many organizations now utilize action learning, and it is applied increasingly throughout the world. Action learning appears in numerous variants, but generically it is a form of learning through experience, “by doing”, where the task environment is the classroom, and the task the vehicle. Two previous reviews of the action learning literature by Alan Mumford respectively covered the field prior to 1985 and the period 1985‐1994. Both reviews included books as well as journal articles. This current review covers the period 1994‐2000 and is limited to publicly available journal articles. Part 1 of the Review was published in an earlier issue of the Journal of Workplace Learning (Vol. 15 No. 2) and included a bibliography and comments. Part 2 extends that introduction with a schema for categorizing action learning articles and with comments on representative articles from the bibliography.

In the last four years, since Volume I of this Bibliography first appeared, there has been an explosion of literature in all the main functional areas of business. This wealth of material poses problems for the researcher in management studies — and, of course, for the librarian: uncovering what has been written in any one area is not an easy task. This volume aims to help the librarian and the researcher overcome some of the immediate problems of identification of material. It is an annotated bibliography of management, drawing on the wide variety of literature produced by MCB University Press. Over the last four years, MCB University Press has produced an extensive range of books and serial publications covering most of the established and many of the developing areas of management. This volume, in conjunction with Volume I, provides a guide to all the material published so far.

While the need for leadership in health care is well recognised, there is still the need to better understand how leadership contributes to improving healthcare services. The body of knowledge concerning improvement has grown significantly in recent years, but evidence about links between leadership and health services improvement remains poor, especially within the UK National Health Service. It remains unclear how and why leadership is important to service improvement, and how leadership development can optimise service improvement.This paper describes a study commissioned by The Health Foundation, exploring the links between leadership behaviours reported by clinicians and managers in NHS organisations and their service improvement work. The study highlights leadership behaviours that appear to be positively associated with NHS improvement work. This paper provides insights into which aspects of leadership are used for different types of improvement work and considers lessons for leadership development.