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The paper aims to present the processing pipeline of an assembly immersive simulation application which can manage the interaction between the virtual scene and user using stereoscopic display and haptic devices. A new set of elements are integrated in a Collaborative Virtual Environment (CVE) and validated using an approach based on subjective and objective users’ performance criteria. The developed application is intended for Assembly/Disassembly (A/D) analysis, planning and training.

A mobility module based on contact information is used to handle the assembly components’ movements through real-time management of collision detection and kinematically constraint guidance. Information on CVE architecture, modules and application configuration process are presented. Impact of device type (3 degrees of freedom (DoFs) vs 6 DoFs) over user’s experience is evaluated. Parameters (number of assembled components and components assembly time) are measured for each user and each haptic device, and results are compared and discussed.

Test results proved the efficiency of using a mobility module based on predefined kinematic constraints for reducing the complexity of collision detection algorithms in real-time assembly haptic simulations. Also, experiments showed that, generally, users performed better with 3 DoFs haptic device compared to 6 DoFs haptic equipment.

The proposed immersive application automates the kinematical joints inference from 3D computer-aided design (CAD) assembly models and integrates it within a haptic-based virtual environment, for increasing the efficiency of A/D process simulations.

In my original efforts, I designated and depicted no less than nine “men” of economics. Essentially, I contended, as man has always tended to create God in his own image and likeness, so economists have fashioned man largely in their discipline's perceived nature and scope. These generic homines economici, that is, have thus been and perhaps cannot really be other than economists' “men”, and the study thereof provides accordingly a meaningful alternative approach to the history, nature and scope of economics itself.

THERE is no doubt that a lot of literary rubbish is current under the name of children's books; there always was; but it has become rather more apparent in recent times. Mr. McColvin, in a useful article in The Library Review, presents a nostalgic sigh for the days of Henty and Fenn and even of the earlier Ballantyne and upon that builds a somewhat severe criticism of the modern children's library. As so often with writers on this theme, he uses no half‐tones and points a rather dismal scene in primary black and white, and his moral is that it would be better to be without these libraries than that they should supply ill‐written, badly devised and quite useless slush which makes no demands upon the child. If this were a complete picture we should agree. It is not; in the first place, it is based mainly on fiction, a very incomplete view of children's books. But, even considering fiction only, while such writers as Noel Streatfeild, Elizabeth Goudge, Arthur Ransome and David Severn (and a dozen others come to the pen) are supplying us with books, it cannot be wholly true. Then, as one of our correspondents implies elsewhere in these pages, children are of many ages and stages, and it is not wrong to give little ones simple things. It is vain to long for the return of the days when the Pilgrim's Progress, Foxe's Martyrs and the Dore editions of Paradise Lost and the Cary translation of Dante's Inferno adorned, and required dusting weekly, on every parlour table, and to many subsequent readers Ballantyne, except for Coral Island, is as dead as the Pharaohs. We do thank Mr. McColvin, however, for bringing children's librarians to that state of vexed irritation which will induce them to reconsider their work, increase their standards and recall the commonplace that their almost entire purpose is to produce intelligent adult readers. The T.L.S., in an appreciation of Mr. McColvin's article, suggests that the influence of the children's librarian can be even greater in this direction than the teacher's, but, if what he asserts is true, through our libraries many children may be deprived of the intellectual capacity to read anything worth while. Does Mr. McColvin really believe that?

WORK study owes much to the Association of British Chemical Manufacturers for the series of notes on the subject which it produces, a debt just increased by the fifth booklet which is a general guide to managers in the industry who may be considering the introduction of an incentive scheme.

The European Union (EU) is not a state, though it has some statelike attributes; it is not an empire, though it includes many former European imperial powers; and it is not a federation, though Euro-federalists seek to make it one. There is, however, no need to argue that the Union is a singularity, nor to invent novel terminology, such as that deployed by “neo-functionalists” and “intergovernmentalists” to capture its legal and political form. The EU is a confederation, but with consociational characteristics in its decision-making styles. This conceptualization facilitates understanding and helps explain the patterns of crises within the Union.

I'VE said it before, and I'll say it again: Eastbourne is an excellent place for a conference, and I set out for it after five years' absence with the hope that its handsome and genial presence would produce something better than the mixture of ordinary, obvious and sometimes inaudible papers that have been a constituent of more than one intervening conference. That towns can affect such occasions is no doubt a farfetched conceit, but they certainly affect me; as soon as I arrived the environmental magic worked, and old friends and new faces were seen in the golden light of perfect autumn weather.

PROJECTS launched early in National Productivity Year are still producing useful results. One of the most commendable of these was the circulation of a questionnaire which reached manufacturing firms in Monmouthshire. It was the idea of No. 3 sub‐committee of the country's Productivity Study Group.