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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.

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.

This paper outlines some of the factors which are important in helping or hindering women with learning disabilities to experience their sexuality in a positive and healthy way. Based on direct experience, the paper presents the factors which must be present for women with learning disabilities to enjoy their sexuality: making choices, giving consent, receiving information, experiencing mutuality, experiencing pleasure, having self‐esteem and having recourse to the law if abused. Conversely, the factors which need to be absent are coercion, oppression, guilt and shame, and unwanted physical consequences. The paper emphasises how important it is that women with learning disabilities and their supporters understand these factors.

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.

Even more than 50 years after the Civil Rights Act of 1964 prohibited discrimination toward a number of groups in employment settings in the United States, workplace discrimination remains a persistent problem in organizations. This chapter provides a comprehensive review and analysis of contemporary theory and evidence on the nature, causes, and consequences of discrimination before synthesizing potential methods for its reduction. We note the strengths and weaknesses of this scholarship and highlight meaningful future directions. In so doing, we hope to both inform and inspire organizational and scholarly efforts to understand and eliminate workplace discrimination.

The discrete Fourier transform (dft) of a fractional process is studied. An exact representation of the dft is given in terms of the component data, leading to the frequency domain form of the model for a fractional process. This representation is particularly useful in analyzing the asymptotic behavior of the dft and periodogram in the nonstationary case when the memory parameter d≥12. Various asymptotic approximations are established including some new hypergeometric function representations that are of independent interest. It is shown that smoothed periodogram spectral estimates remain consistent for frequencies away from the origin in the nonstationary case provided the memory parameter d < 1. When d = 1, the spectral estimates are inconsistent and converge weakly to random variates. Applications of the theory to log periodogram regression and local Whittle estimation of the memory parameter are discussed and some modified versions of these procedures are suggested for nonstationary cases.