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The purpose of this paper is to present a hierarchical circuit synthesis system with a hybrid deterministic local optimization – multi‐objective genetic algorithm (DLO‐MOGA) optimization scheme for system‐level synthesis.

The use of a local optimization with a deterministic algorithm based on linear equations which is computationally efficient and improves the feasibility of designs, allows reduction in the number of MOGA generations required to achieve convergence.

This approach reduces the total number of simulation iterations required for optimization. Reduction in run time enables use of full transistor‐level models for simulation of critical system‐level sub‐blocks. Consequently, for system‐level synthesis, simulation accuracy is maintained. The approach is demonstrated for the design of pipeline analog‐to‐digital converters on a 0.35 μm process.

The use of a hybrid DLO‐MOGA optimization approach is a new approach to improve hierarchical circuit synthesis time while preserving accuracy.

Few areas of public service exist in which those who work to provide them receive the recognition their efforts justly deserve, and regretably no where more so than in the local health and consumer protection services. These services have a long history of public indifference, which in years past bordered on contempt. They were labelled “public servants” in a manner that implied they were the personal servants of ratepayers, apointed by them and paid from monies they provided.

In a recent reference to changes brought about by the local government reorganisation of 1974, we criticised some of the names given to the new areas. Some of these name changes have made difficulties for those who follow from afar the doings of local authorities, as well as raising the ire of local people. Local names, however, are not the only casualty. The creation of new and larger governmental organisations rarely, if ever, results in economy and as anticipated, it was not long before the new local authorities were being directed to embrace financial stringency and all that it incurs. One such other casualty has been the loss of so many of the annual reports of local authority departments, very few now arriving at BFJ offices. In every case, the reason has been the same—severe restrictions on spending. Not that this was not necessary in many fields, but in respect of annual reports, we are convinced it was false economy. For so many of the reports, it was our pleasure to review them in the pages of BFJ. A prominent Labour politician was once heard to refer to them as “hard and dry reports for hard and dry officials”. It all depends probably on what you are looking for in them. Statistics there must be but most enforcement officers and public analysts, endeavour to keep these to the minimum, the general impression being that these are “dry”. If you are looking for trends, for comparison of the year under review with preceding years and then for comparing the results reported in one part of the country with another, where the population, eating habits, consumer reactions may be different, the tables of statistics are highly important.

In a previous article we have called attention to the danger of eating tinned and bottled vegetables which have been coloured by the addition of salts of copper and we have urged upon the public that no such preparations should be purchased without an adequate guarantee that they are free from copper compounds. Copper poisoning, however, is not the only danger to which consumers of preserved foods are liable. Judging from the reports of cases of irritant poisoning which appear with somewhat alarming frequency in the daily press, and from the information which we have been at pains to obtain, there can be no question that the occurrence of a large number of these cases is to be attributed to the ingestion of tinned foods which has been improperly prepared or kept. It is not to be supposed that the numerous cases of illness which have been ascribed to the use of tinned foods were all cases of metallic poisoning brought about by the action of the contents of the tins upon the metal and solder of the latter. The evidence available does not show that a majority of the cases could be put down to this cause alone; but it must be admitted that the evidence is in most instances of an unsatisfactory and inconclusive character. It has become a somewhat too common custom to put forward the view that so‐called “ptomaine” poisoning is the cause of the mischief; and this upon very insufficient evidence. While there is no doubt that the presence in tinned goods of some poisonous products of decomposition or organic change very frequently gives rise to dangerous illness, so little is known of the chemical nature and of the physiological effects of “ptomaines” that to obtain conclusive evidence is in all cases most difficult, and in many, if not in most, quite impossible. A study of the subject leads to the conclusion that both ptomaine poisoning and metallic poisoning—also of an obscure kind—have, either separately or in conjunction, produced the effects from time to time reported. In view of the many outbreaks of illness, and especially, of course, of the deaths which have been attributed to the eating of bad tinned foods it is of the utmost importance that some more stringent control than that which can be said to exist at present should be exercised over the preparation and sale of tinned goods. In Holland some two or three years ago, in consequence partly of the fact that, after eating tinned food, about seventy soldiers were attacked by severe illness at the Dutch manœuvres, the attention of the Government was drawn to the matter by Drs. VAN HAMEL ROOS and HARMENS, who advocated the use of enamel for coating tins. It appears that an enamel of special manufacture is now extensively used in Holland by the manfacturers of the better qualities of tinned food, and that the use of such enamelled tins is insisted upon for naval and military stores. This is a course which might with great advantage be followed in this country. While absolute safety may not be attainable, adequate steps should be taken to prevent the use of damaged, inferior or improper materials, to enforce cleanliness, and to ensure the adoption of some better system of canning.

DURING the past 40‐odd years or so, a number of experimental aeroplane types have been invented, visualized, designed, constructed and even flown which, in a quite unorthodox manner, had neither behind the wing nor in front of it any sort of stabilizing and/or controlling surfaces.