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A great deal has been published recently concerning expert systems and the viability of using expert system shells and a useful feature published in Systems International, April, 1988, pp 23–38, provides a summary of these shells and their market. There is, of course, great activity in all aspects of development of these systems. For example, the European experts systems market alone is said to be growing at a rate of 50 per cent a year and should reach $1 billion by 1991. In an introduction to this summary it is stated that some 40 per cent of expenditure on artificial intelligence (AI) is on software, and of this a third comes from the sale of AI languages. This feature on expert systems looks at the human and organisational problems to be considered when implementing such a system. It also outlines the market for the systems, and surveys some of the products. Finally, the limitations inherent in the rules govering expert systems shells are discussed. In an article in this review Sue Ottley, a psychologist in the human factors group at ICLs Marketing and Technical Strategy Centre, warns of some human and organisational problems to consider when implementing an expert system, from capturing an expert's knowledge to gaining user acceptance. She says that there are wide ranging concerns at the organisational level, which includes changes in the information flow patterns within an organisation, changes that can be brought about to the authority and decision‐making hierarchies and the effects of changing the locus of control and/or authority within an organisation. This latter state can have a strong effect on the acceptance of an expert system and needs to be planned for in advance. Otherwise, unplanned change or uncontrolled change, can, she maintains, be disruptive to even the most well developed and stable organisation.

Because of the special “State of the States” issue of Library Hi Tech and other circumstances beyond my control, the four quarterly “Comp Lit” compilations for 1996 appear here in a single and possibly peculiar chunk. A lot changes in a year of personal computing, but on reflection it seemed useful to include the citations and comments as I originally wrote them.

The Protection of Consumers (Trade Descriptions) bill which, owing to the General Election, did not quite make the Statute Book in the last Parliament, is, at the moment of writing, passing through its readings, with every likelihood of becoming law in the near future. It has been criticised for the extent of the control to be exercised over general trading and that in “coddling the customer” it will place unreasonable responsibilities upon retailers. In fact, it is impossible to foresee just how far its provisions may extend, but there will be few who will disagree that new and more searching requirements are long overdue.

In the last few months I have been to two major conferences on work study related topics. One was in Toronto, the other in Cambridge! It is interesting to note the differences between the two.

IF THERE IS one thing that is troubling the Government — or should be — as it already is a prime worry to the population of Britain (and specially those immediately affected by it) it is the unacceptable level of unemployment.

The initial shock of devaluing the currency, after so many promises that it would not take place, has passed; only the uncertainty and apprehension remain. It seems an idle exercise to compare the present state of the country's economy with other periods in recent history, such as when in the first Labour Government, we went off the gold standard; at that time, shock was indeed profound and again, the French were cock‐a‐hoop, but the position was complicated by the huge inter‐indebtedness of the Allies in the First War. Or the first devaluation after the Second World War, but both periods were also characterized by public waste and profligate spending. Now, we have to obtain foreign loans and financial backing to keep going, and it is this aspect of the present devaluation which will probably far outweigh any positive advantages. The country's massive external debts were increased by approximately one‐seventh overnight, probably wiping out completely all the repayments made at such great effort since the War. Devaluation of the currency cannot be seen as anything but a grievous blow to the country, presaging hard times ahead for everyone. When promises were being made that devaluation would not take place, there can be little doubt that these were honestly made and, at the time, believed in, for no Government of a country with imports always exceeding exports, would impose such a burden on its people willingly. It must then have been forced upon them.

In this second part of the report on Printed Circuit World Convention IV held at the Tokyo Prince Hotel, Tokyo, from 3–5 June 1987, a general synopsis of the content of the papers presented in the eighteen technical sessions will be given. As three sessions were run in parallel throughout the 2½‐day conference, and therefore not all presentations were heard by those reporting on the technical programme, a number of them have been briefly summarised from the Convention Proceedings.

The purpose of this study is to highlight the direct fabrication of rapid tooling (RT) with desired mechanical, tribological and thermal properties using fused deposition modelling (FDM) process. Further, the review paper demonstrated development procedure of alternative feedstock filament of low-cost composite material for FDM to extend the range of RT applications.

The alternative materials for FDM and their processing requirements for fabrication in filament form as reported by various researchers have been summarized. The literature demonstrates the role of various post-processing techniques on surface finish of FDM prints. Further, low-cost materials for feedstock filament have been investigated experimentally to check their adaptability/suitability for commercial FDM setup. The approach was to realize the requirements of FDM (melt flow rate, flexibility, stiffness, glass transition temperature and mechanical strength), necessary for the successful run of an alternative filament. The effect of constituents (additives, plasticizers, surfactants and fillers) in polymeric matrix on mechanical, tribological and thermal properties has been investigated.

It is possible to develop composite material feedstock as filament for commercial FDM setup without changing its hardware and software. Surface finish of the parts can further be improved by applying various post-processing techniques. Most of the composite parts have high mechanical strength, hardness, thermal stability, wear resistant and better bond formation than standard material parts.

Future research may be focused on improving the surface quality of parts fabricated with composite feedstock, solving issues related to the uniform distribution of filled materials during the fabrication of feedstock filament which in turns further increases mechanical strength, high dimensional stability of composite filament and transferring the technology from laboratory scale to various industrial applications.

Potential applications of direct fabrication with RT includes rapid manufacturing (RM) of metal-filled parts and ceramic-filled parts (which have complex shape and cannot be rapidly made by any other manufacturing techniques) in the field of biomedical and dentistry.

This new manufacturing methodology is based on the proper selection and processing of various materials and additives to form high-performance, low-cost composite material feedstock filament (which fulfil the necessary requirements of FDM process). Finally, newly developed feedstock filament material has both quantitative and qualitative advantage in RT and RM applications as compared to standard material filament.