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The evaluation of electromagnetic transients in overhead power lines due to nearby lightning return strokes requires accurate models for the calculation of both the incident lightning electromagnetic pulse (LEMP) and the effects of coupling of this field to the line conductors. Considering also the complexity of distribution networks in terms of their topology and the presence of power system components and protection devices, the implementation of the LEMP-to-transmission-line coupling models into software tools used to represent the transient behavior of the entire network is of crucial importance. This paper reviews the most significant results obtained by the authors concerning the calculation of lightning-induced voltages. First, the theoretical basis of advanced models for the calculation of LEMP-originated transients in overhead power lines is illustrated; then, the relevant experimental validation using: 1) reduced-scale setups with LEMP and nuclear electromagnetic pulse (NEMP) simulators and 2) full-scale setups illuminated by artificially initiated lightning are reported. Finally, the paper presents comparisons between simulations and new experimental data consisting of measured natural lightning- induced voltages on a real distribution network in northern Italy, correlated with data from lightning location systems. [ABSTRACT FROM AUTHOR]

The alpine village of Lamosano, Belluno, Italy, located near a wide and active landslide, has been seriously threatened by ground instabilities since 1960. In this paper, the results obtained by two different remote-monitoring techniques, synthetic aperature radar interferometry and three-dimensional laser-scanner imaging, planned for Lamosano hazard assessment, are presented. Both techniques compare images taken at different times to map and classify changes that occurred on the imaged scenario. The radar and laser data are gathered at the same dates with about ten-month temporal separation. The displacements measured separately by each of the two techniques highlight a similar sliding motion on the Lamosano village area, providing a good validation to each other and contributing to the definition of the village instability hazard. [ABSTRACT FROM AUTHOR]

The article presents information on the International Conference on Software Maintenance held in Bari, Italy which was sponsored by the IEEE Computer Society Technical Council on Software Engineering in 1997. The program for this conference addressed important maintenance issues, such as the year 2000 problem and preparing for the transition to network computing through paper presentations, industry reports panel discussions, tools demonstration and keynote addresses. The first paper under the title "Identifying Modules via Concept Analysis," by Michael Siff and Thomas Reps, presents a technique that addresses an important problem in reengineering and restructuring legacy code that is identifying modules. The second paper under the title "Measuring and Evaluating Maintenance Process Using Reliability, Risk and Test Metrics," by Norman F. Schneidewind, presents a measurement model that addresses an important problem in software maintenance measurement, measuring the stability of the maintenance process.