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The reducing transformation and global optimization technique called Alienor has been developed in the 1980s by Cherruault and Guillez. These methods are based on the approximating properties of α ‐dense curves. The aim of this work is to give a very large class of functions generating α ‐dense curves in a hyper‐rectangle of Rⁿ.

In the paper the optimization procedure of a direct current motor with a hybrid excitation has been presented. The excitation system consists of a shunt field winding disposed around field pole and permanent magnet, both acting in parallel. The field distribution in motor for various magnet and field pole dimensions has been determined using finite element method. The flux linkage with the armature winding has been computed. Demagnetizing effect of armature current was taken into account. The optimal permanent magnet and the field pole dimensions, ensuring minimum total cost of purchase and work during assumed period of time were calculated. Motor characteristics e.g. rated torque, rated current, speed regulation limit were used as constraints. In worked up algorithm and computer program Carroll internal penalty function method was used. Some basic suggestions tor design of optimal hybrid excited dc motors with parallel permanent magnet and electromagnetic excitation are given.

THE use of liquid oxygen as an oxidizer for various fuels in liquid rocket propellent systems is not new. Professor Goddard used liquid oxygen in his rocket experiments and the well known German V‐2 rockets used this material as an oxidizer. However, its effect on non‐metallic materials ordinarily used in rocket systems was not investigated until recent years. This investigation was prompted by phenomena which had been experienced by rocket engine and rocket aircraft manufacturers and by suppliers of the material. It was observed that when some organic materials came in intimate contact with liquid oxygen they became prone to detonation when subjected to certain impact energies. This was undoubtedly due to the formation of unstable organo‐peroxide compounds which when impacted released high levels of energy resulting in an explosion. Specifically, when liquid oxygen was accidently spilled on asphalt and inadvertently stepped on, the asphalt would often explode. Also, leather gaskets immersed in liquid oxygen and subjected to surge impact detonated with disastrous effects.

I‐V characteristics of GaAs n‐i‐n structures are calculated by considering impact ionization of carriers. Impact ionization at reverse‐biased n‐i junction becomes a cause of steep current rise when an acceptor density in the i‐layer is high. It is shown that an optimum acceptor density exists to keep a good isolation. Photoconduction transients of GaAs n‐i‐n structures are also simulated, and are shown to be strongly affected by existence of n‐i junctions.

‘The application of computers to teaching and learning is a logical development in the evolution of educational technology, although at present the ultimate benefits can be but dimly foreseen. The realization of this potential will require concentrated research and development efforts which can only profitably flourish within the ambit of a national programme of work.’ So opens a recently published report of the National Council for Educational Technology addressed both to Ministers and to all engaged in the education industry. What lies behind this bald statement with its overtones of brash prophecy, veiled threat, and blatant jingoism? I would like to explore some of the reasons for thinking that a revolution in education, as far reaching as the Copernican revolution in astronomy, is now within the realm of possibility.

THE rapid growth and development of the aircraft industry has necessitated prompt decision and action in handling the many problems in connexion with the erection and equipment of aerodrome buildings, hangars, workshops and factories. In the urgency of providing the industry with all its varied requirements, it is not surprising that lire insurance planning has to a very large extent been crowded out. There are, no doubt, several reasons for this and in the welter of plans and designs that have been drawn and re‐drawn, the necessity of complying with the clients' requirements, numerous rules and regulations of local authorities and Acts of Parliament, etc., the benefits which accrue to wise planning from a fire insurance point of view have not always been fully appreciated. The need for increased output has in many cases pressed very heavily on those making the necessary preparations, and frequently no serious thought has been given to fire insurance planning. There are some persons who are under the impression that, having conformed with the numerous rules and requirements, they have carried out all that can be done in this direction.

An IBM PC Library Users Group was organized during the two‐day Library Software Conference held in Columbus, OH, October 2–4. Initial goals of the group and an early schedule of activities were agreed upon by the conferees who met until 10:30 p.m. in a room crowded to capacity. The M300 and PC REPORT will serve as the group's communication forum as well as its initial administrative agent.

The calculation of quasistationary magnetic fields and electrostatic fields of several objects is presented in the paper. In the range of the magnetic fields of coils and transformer systems parallelepiped calculation regions are assumed. In the range of electrostatic fields analysis of the field in tanks of different shape storing inflammable liquids was undertaken. Fast subroutines using finite differences [FDM] to calculate the field were employed. These subroutines are based on the Fast Fourier Transform (FFT).

The M300/IBM PC Users Group is rapidly gaining new members and has been offered a Bulletin Board in Des Moines, IA for its use. What is needed now are persons across the country who are willing to work with the administrative agent to establish a leadership structure, to plan the group's initial meeting during the Chicago 1985 ALA conference (July 6–11), to develop the parameters of the bulletin board, to set membership criteria, to develop users group goals and objectives, to develop and lead local chapters, and to report news and activities to M300. Back issues of M300 and PC REPORT contain an application form which may be used for membership, suggesting, or reporting purposes. We particularly need persons who are willing to be officers and volunteers.

When in‐plant and college‐based courses are run for supervisors and managers, it is conventional to use a U‐shaped seating arrangement in the training room to promote participation and discussion. However, at each class session, people will tend to sit with the same companions habitually, which may be more comfortable, but less productive than if they sat with different people each time.