Abstract
The images of Electrical Impedance Tomography are reconstructed using certain approximations and have a low spatial resolution. It is therefore proposed, in order to detect the presence of such tumors, to use neural networks for the recognition of typical patterns in the raw data rather than in the reconstructed images. The results obtained with several types of targets in vitro confirm the feasibility of this approach.

Abstract
This contribution describes a Videotex terminal with photographic capabilities based on a personal computer (PC). This system takes advantage of a recently available support - the Integrated Services Digital Network (ISDN) - which represents a significant improvement in the performance of communication systems, and is intended to offer a new and practical service while maintaining compatibility with the Alphamosaic Videotex.

Abstract

Abstract
We argue that in order to exploit both Independent And-and Or-parallelism in Prolog programs there is advantage in recomputing some of the independent goals, as opposed to all their solutions being reused. We present an abstract model, called the Composition-tree, for representing and-or parallelism in Prolog programs. The Composition-tree closely mirrors sequential Prolog execution by recomputing some independent goals rather than fully re-using them. We also outline two environment representation techniques for And-Or parallel execution of full Prolog based on the Composition-tree model abstraction. We argue that these techniques have advantages over earlier proposals for exploiting and-or parallelism in Prolog. © 1993 Ohmsha, Ltd. and Springer.

Abstract
The performance of frequency-modulated (FM) subcarrier-multiplexed systems is assessed using Volterra series analysis to model laser nonlinear distortion accurately. The intermodulation-power spectral density and the carrier-to-intermodulation ratio are then determined. The performance of these systems is investigated by considering all noise contributions: intermodulation and relative intensity noise in the transmitter and receiver thermal and shot noise. Optimum performance is also identified. A 62-channel FM video system occupying the bandwidth of 2.7-5.2 GHz provides an illustrative example.

Abstract
The paper describes the results to date of the RACE project R2005. The project addresses the optical generation and fibre delivery of mm-wave signals for future mobile radio and remote customer access connections. The authors identify potential application areas and appropriate performance targets for such fibre/mm-wave systems. The major issue identified is the need to achieve low-cost antenna units due to the large number of such units that would be required; this arises from the limited propagation distances achieveable at mm-wave frequencies. A brief review of current optical methods for the generation of mm-waves allows the identification of the inadequacies of these techniques and leads to a description of a new method, developed for the project, that overcomes most of the disadvantages outlined earlier.