S. K. Ghosh, S. K. Sarkar, S. Chakraborty
DESIGN AND DEVELOPMENT OF A FIBER OPTIC INTRINSIC VOLTAGE SENSOR

A direct and alternating voltage measurement scheme utilizing optical polarization phenomena has been reported. Accordingly a single mode fiber optic sensor has been developed which is intrinsic in nature. A polarization phase shift can be observed between input and output laser light when S.M. fiber of sufficient length is subjected to optimum electric field. The phase shift is due to electrostriction and electro optic Kerr effect. The phase shift is measured through polarization sensitive detection. Voltages (DC & AC) are calibrated in terms of phase shift. Theory has been formulated to depict the variation of phase shift with impressed alternating voltage on the set-up. Closeness between theoretical and experimental results is encouraging. The range of voltage measured through this technique is up to a few hundred volts for DC and AC with resolution of 1 Volt. As per construction of the fiber sensor sensitivity is dependent on the length of the fiber and spacing between electrodes. To minimize the measurement error referencing technique is preferable, at the same time to remove the nonlinear relationship between input and output ANN based linearization technique has been employed.

Karel Zalis
DEVELOPMENT OF COMPLEX SYSTEM FOR MEASUREMENT AND EVALUATION OF PD ACTIVITY

Expert systems are used for the evaluation of the actual state and future behaviour of insulating systems of electrical machines and equipment, especially for the evaluation of discharge activity in high voltage insulation by partial discharge (PD) measurement. Several rule-based expert systems were developed in the High Voltage Laboratory of the Czech Technical University in Prague for these purposes in the co-operation with top diagnostic workplaces in the Czech Republic. Nowadays, the complex system for the evaluation of PD measurement including software and hardware facilities has been developed. Two expert systems for the evaluation of PD activity work in this complex evaluating system: a rulebased expert system performs an amplitude analysis of PD impulses for determining the damage of the insulation system, and a neural network is used for a phase analysis of PD impulses to determine the kind of PD activity. Both expert systems operate simultaneously and special software ensures co-ordination between them.

C. Temneanu, O. Postolache, P. Girão, J. Pereira
FUZZY MODELING OF MEASUREMENT DATA IN WATER QUALITY ASSESSMENT

The paper discusses a possible solution for water quality assessment based on a virtual system and on intelligent processing structures. Referring to the intelligent processing, a practical approach concerning the fuzzy based solutions in data sensor correction is presented. Several types of fuzzy models are designed, tested and implemented in order to perform the on-line temperature correction of the acquired information from pH, turbidity and conductivity sensors. As the fuzzy architectures used are mentioned the Mamdani and TS by fuzzy clustering techniques. Elements related the virtual system hardware and LabVIEW * temperature fuzzy corrector" are also presented.

Jiří Novák, Petr Kocourek
TESTING THE DISTRIBUTED SYSTEMS FOR THE HARSH ENVIRONMENT

This paper is focused on comparison of three proposed methods for testing the modules and the complex installations of distributed systems (fieldbuses) for the use in a harsh industrial environment and applications, where the system reliability is a crucial requirement. The methods are defined, their advantages and disadvantages are explained and expected test results are presented. Special auxiliary test equipment required for testing is described, especially in terms of its necessary features. Both the test methods are intended for the equipment manufacturers, system integrators and possibly users of distributed systems. The Controller Area Network (CAN) standard is used as an application example, but most of the results are ommonly valid.

J. Mochol, G. Bencze, Z. Szillasi, P. Raics, Zs. Szabo, J. Molnar
OPTICAL POSITION MONITORING SYSTEM FOR THE CENTRAL MUON DETECTOR OF THE CMS EXPERIMENT AT CERN

The CMS experiment (Compact Muon Solenoid) [1,2] is one of the experiments on the future Large Hadron Collider at CERN (European Organization for Particle Physics). To achieve the best performance in the reconstruction of the particle tracks the knowledge of the positions of the tracking detectors is required. In this paper the optical position monitoring system of the Central Muon part of the CMS Detector is described.