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This paper presents several methods for enhancing computational efficiency in both static and dynamic analysis of structural systems with localized non‐linear behaviour. A significant reduction of computational effort with respect to brute‐force non‐linear analysis is achieved in all cases at the insignificant (or no) loss of accuracy. The presented methodologies are easily incorporated into a standard computer program for linear analysis.

An assessment is made of a 4‐node quadrilateral membrane element with one rotational and two translational degrees of freedom per node, as formulated by Taylor and Simo. The element, QC9, is formed by degeneration of the 9‐node Lagrange element and condensation of the centre degrees of freedom. An 8‐point, modified reduced integration scheme is implemented in this element, QC9(8), to improve on the 3 × 3 quadrature performance, yet avoid the additional rank deficiency due to reduced integration (2 × 2). QC9(8) performs as good or better than all elements surveyed. It is shown that a similar degeneration of the 16‐node Lagrangian element can be carried out, but that the resulting element fails the patch test.

The advantages of a direct superposition of the Ritz vector in dynamic response analysis (developed by Wilson, Yuan, and Dickens in 1982 and termed the WYD method) are that: no iteration is involved; the method is at least four times faster than the subspace iteration method; and fewer Ritz vectors are necessary for the mode superposition of dynamic response analysis than exact eigenvectors are used. The major purpose of this paper is to illustrate that the WYD method can also be used as a general approximate algorithm to calculate eigenvalues and eigenvectors. The WYD and Lanczos algorithms are very similar and a formula that relates the two is given in this paper. Although the exact algebraic value of only a single eigenvector of a multi‐eigenvalue can be calculated using either the WYD or Lanczos methods, an artificial round‐off is presented that can be used to solve the eigenvalue problem. A method of estimating the error introduced by the WYD method is also developed. A dynamic substructuring technique, based on the WYD method, and which assumes that the connectivities on the interfaces among the substructures need not be considered is also presented.

The final report of the Butter Regulations Committee has now been published and it is earnestly to be hoped that Regulations based on the Committee's Recommendations will at once be framed and issued by the Board of Agriculture. It will be remembered that in an Interim Report the Committee recommended the adoption of a limit of 16 per cent. for the proportion of water in butter, and that, acting on this recommendation, the Board of Agriculture drew up and issued the “Sale of Butter Regulations, 1902,” under the powers conferred on the Board by Section 4 of the Food Act of 1899. In the present Report the Committee deal with the other matters referred to them, namely, as to what Regulations, if any, might with advantage be made for determining what deficiency in any of the normal constituents of butter, or what addition of extraneous matter other than water, should raise a presumption until the contrary is proved that the butter is not “genuine.” The Committee are to be congratulated on the result of their labours—labours which have obviously been both arduous and lengthy. The questions which have had to be dealt with are intricate and difficult, and they are, moreover, of a highly technical nature. The Committee have evidently worked with the earnest desire to arrive at conclusions which, when applied, would afford as great a measure of protection—as it is possible to give by means of legislative enactments—to the consumer and to the honest producer. The thorough investigation which has been made could result only in the conclusions at which the Committee have arrived, namely, that, in regard to the administration of the Food Acts, (1) an analytical limit should be imposed which limit should determine what degree of deficiency in those constituents which specially characterise butter should raise a presumption that the butter is not “genuine”; (2) that the use of 10 per cent. of a chemically‐recognisable oil in the manufacture of margarine be made compulsory; (3) that steps should be taken to obtain international co‐operation; and finally, that the System of Control, as explained by various witnesses, commends itself to the Committee.

Compiled by K.G.B. Bakewell covering the following journals published by MCB University Press: Facilities Volumes 8‐18; Journal of Property Investment & Finance Volumes 8‐18; Property Management Volumes 8‐18; Structural Survey Volumes 8‐18.

Index by subjects, compiled by K.G.B. Bakewell covering the following journals: Facilities Volumes 8‐18; Journal of Property Investment & Finance Volumes 8‐18; Property Management Volumes 8‐18; Structural Survey Volumes 8‐18.

Compiled by K.G.B. Bakewell covering the following journals published by MCB University Press: Facilities Volumes 8‐18; Journal of Property Investment & Finance Volumes 8‐18; Property Management Volumes 8‐18; Structural Survey Volumes 8‐18.

Compiled by K.G.B. Bakewell covering the following journals published by MCB University Press: Facilities Volumes 8‐18; Journal of Property Investment & Finance Volumes 8‐18; Property Management Volumes 8‐18; Structural Survey Volumes 8‐18.

Computational algorithms for finite element dynamic analysis of large‐scale structural problems that exploit both concurrent and parallel features of multiple instruction multiple data streams computers are presented. A new computer program architecture is used in which large finite element domains are automatically divided into subdomains. The number of subdomains generated is equal to the number of available processors. The spatial solution is obtained using a basis of orthogonal vectors. The temporal solution is computed exactly. Discussion is focused on the concurrent generation of global Ritz vectors. Examples run on a hypercube multiprocessor confirm the potential of the proposed scheme.