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DC urban light railway systems are used for public transportation in many towns worldwide. In these systems, short-circuit currents are often similar, both in steady-state magnitude and in rate-of-rise, to normal operation currents. In order to properly set the protection relays, to obtain short-circuit discrimination and to avoid nuisance trippings, it is important to analyze short circuit and normal operation current patterns. It is also important to highlight that normal operation current patterns are not only those related to rolling stock acceleration, but also to zone commutation. This paper presents the results of several measurement campaigns, performed for this purpose, on the tram network of Turin, Italy. The measurements results are then used to propose optimized settings for the installed overcurrent protections. [ABSTRACT FROM AUTHOR]

This paper presents the problem of power penetration of photovoltaic (PV) systems in urban networks. After a qualitative problem description, two different environments for PV systems have been analyzed: rural and urban networks. Concerning the rural network, a single line has been simulated in order to evaluate the relation between the number of PV systems installed along the line and the maximum PV power installable. In the second part of this paper, possible problems due to power penetration have been examined concerning a clustered PV system that will be installed in the city of Torino (Italy) within the ambit of the EU project called POLYCITY. [ABSTRACT FROM AUTHOR]

Grading programming assignments of courses on distributed programming can greatly benefit from extensive testing, especially if quality aspects such as portability, robustness, security, and performance have to be evaluated. This paper presents a framework that was developed at the Turin Polytechnic, Turin, Italy, to enable seamless and fast implementation of Web portals for automated management of student programming assignments. By using a computational grid facility to schedule testing jobs on different hosts, the framework offers high flexibility and scalability, thus enabling computationally intensive tests and some kinds of distributed tests, such as portability tests and field tests, which otherwise would be difficult to automate. The grid can be made of ordinary and even nondedicated or dismissed PCs, which, according to the authors' experience, is enough to offer students online extensive testing services. The framework was successfully used in two courses on distributed programming, located at different sites, partially overlapped in time, and attended by a total of 60 students. However, the framework should be scalable enough to work with increasing numbers of students and courses. [ABSTRACT FROM AUTHOR]