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Shells are widely used structural systems in engineering practice. These structures have been used in the civil, automobile and aerospace industries. Many shells are designed using the finite element analysis through the conventional and costly trial and error scheme. As a more efficient alternative, optimization procedures can be used to design economic and safe structures.

This paper presents developments, integration and applications of reliable and efficient computational tools for the structural optimization of variable thickness plates and free‐form shells. Topology, sizing and shape optimization procedures are considered here. They are applied first as isolated subjects. Then these tools are combined to form a robust and reliable fully integrated design optimization tool to obtain optimum designs. The unique feature is the application of a flexible integrally stiffened plate and shell formulation to the design of stiffened plates and shells.

This work showed the use of different optimization strategies to obtain an optimal design for plates and shells. Both topology optimization (TO) and structural shape optimization procedures were considered. These two optimization applications, as separate procedures produce new designs with a great improvement when compared to the initial designs. However, the combination of stiffening TO and sizing optimization using integrally stiffened shells appears as a more attractive tool to be used. This was illustrated with several examples.

This work represents a novel approach to the design of optimally stiffened shells and overcomes the drawbacks of both topology optimization and structural shape optimization procedures when applied individually. Furthermore, the unique use of integrally stiffened shell elements for optimization, unlike conventional shell‐stiffening optimization techniques, provided a general and extremely flexible tool.

The goal of structural optimization is to find the best possible configuration that minimizes the objective function and satisfies a set of constraints. Here we present a method based on the evolutionary structural optimization method, where the quality of the solution is improved by avoiding the chain‐like sets of elements which are sources of potential kinematic instabilities, and by including local error estimators. Both of these enhancements are employed to activate refining the mesh so as to obtain accurate and stable solutions as the volume removal proceeds. Several related contributions of Professor E. Hinton are cited.

The ENGINEERING, MARINE, WELDING AND NUCLEAR ENERGY EXHIBITION at Olympia to be opened by Sir Christopher Hinton, F.R.S., M.A., Hon.D.Eng., M.I.C.E., M.I.Mech.E., Managing Director (Industrial Group) U.K. Atomic Energy Authority, on Thursday, 29th August, is held in alternating years and draws both Home and Overseas visitors.

In finite element analysis of pile driving, the nodes of the finite element mesh are the most important locations for output stresses. Especially at the pile‐soil interface, it is essential to obtain accurate nodal stresses. Several global and local stress smoothing methods available in the literature were reviewed and examined. Global methods are found to be computationally expensive, so results obtained from several local stress smoothing methods are compared. It is shown that accurate nodal stresses can be obtained by approximating the stress distribution inside four‐element patches by a polynomial with order equal to the order of the shape functions. Equally good results can be obtained by approximating the stress distribution inside each element by a bilinear surface. When a method taking into account both equilibrium and boundary conditions was applied, a set of ill‐conditioned matrices was produced for the four‐element patches. Such methods are therefore not recommended.

SEPTEMBER, as always, sees us contemplating our activities for the winter months. Exigencies of publishing compel us to write these notes a short time before that month begins, and our contemplation of things this year is coloured by the now rather remote possibility that September may bring the invasion that has been the shadow ahead for a year or more. To plan in a twilight time, as it were, is more than ordinarily difficult, and yet it is a commonsense and correct course to go on, not as if nothing could happen, but to the full extent of our means as they exist. Otherwise general paralysis would occur every time our statesmen warned us of possible attacks. There is no fear of such premature paralysis, however, as our people only want to be up and doing “with a heart for any date.”

AT intervals the rules and regulations of libraries should be scrutinized. They are not in themselves sacrosanct as is the constitution of the Realm, but many exist which no longer have serviceable qualities. Nevertheless, so long as a rule remains in force it should be operative and its application be general and impartial amongst readers; otherwise, favouritism and other ills will be charged against the library that makes variations. This being so, it is imperative that now and then revision should take place. There is to‐day a great dislike of discipline, which leads to attacks on all rules, but a few rules are necessary in order that books may be made to give the fullest service, be preserved as far as that is compatible with real use, and that equality of opportunity shall be given to all readers. What is wanted is not “no rules at all,” but good ones so constructed that they adapt themselves to the needs of readers. Anachronisms such as: the rule that in lending libraries forbids the exchange of a book on the day it is borrowed; the illegal charge for vouchers; insistence that readers shall return books for renewal; the rigid limiting of the number of readers' tickets; or a procrustean period of loan for books irrespective of their character—here are some which have gone in many places and should go in all. Our point, however, is that rules should be altered by the authority, not that the application of rules should be altered by staffs. The latter is sometimes done, and trouble usually ensues.

This chapter introduces the volume’s theme by describing the challenges of sustainability in the agri-food industry and the critical role of agri-food supply chains. Following a description of traditional and sustainable supply chain management practices, we discuss the likely characteristics of sustainability-oriented innovations and how organizations pursuing higher levels of economic, social, and environmental performance will need to adapt their capabilities.

Drawing on the emerging concepts and practices from sustainable supply chain management as well as traditional and emerging concepts from innovation, we develop general propositions and expectations about how organizations might address sustainable effectiveness in their supply chains. The importance of the agri-food industry to all three pillars of sustainable effectiveness and predictions about the inability to feed future populations gives the discussion a certain urgency.

Sustainability-oriented innovations in the agri-food supply chain are different from traditional innovations. We develop propositions regarding the driving motivations, their nature and scope (i.e., more radical and systemic than incremental and focused), and the importance of a multi-stakeholder approach. The 10 cases presented in the volume are summarized.

THE article which we publish from the pen of Mr. L. Stanley Jast is the first of many which we hope will come from his pen, now that he has release from regular library duties. Anything that Mr. Jast has to say is said with originality even if the subject is not original; his quality has always been to give an independent and novel twist to almost everything he touches. We think our readers will find this to be so when he touches the important question of “The Library and Leisure.”

Aims to carry out a consumer intervention study to evaluate the impact of an over‐the‐counter herbal weight management product (Zotrim®) on weight and waist circumference.

Overweight women were recruited using local media and 61 passed initial screening to begin a four‐week intervention using a free sample of Zotrim at a dosage corresponding to manufacturers’ recommendations. A total of 56 subjects completed the study, but data on all 61 were included in the “intention to treat” analysis.

There was a self‐reported mean weight loss of 1.79kg (0.45kg per week) at week 4. Data on perceived hunger and fullness from three sets of questionnaires suggested that subjects felt less hungry between meals and fuller after meals at weeks 1 and 4 compared with base‐line. This is likely to have impacted on energy intake and may account for the weight loss. Average weight loss as a percentage of baseline was 2.3 per cent, but this masked a broad range, suggesting that some subjects benefited more than others. Taking into account adjusted guidelines for clinically significant weight loss, 23 per cent of subjects achieved this cut‐off, suggesting that their risk of chronic disease had reduced. Similarly, waist circumference (an independent measure of disease risk) decreased by an average of 4.3cm during the four‐week period. This reduced the number of subjects exceeding SIGN guidelines for central obesity from 93 per cent to 83 per cent.

Adds to the body of knowledge by proring that Zotrim can aid weight loss and help reduce waist circumference.