Journal:Informatica
Volume 23, Issue 3 (2012), pp. 405–425
Abstract
The paper deals with the problem of high-school time-tabling that is important in applications, but hard for solving. The algorithm is presented for timetabling based on Multi-start and Simulated Annealing with parameters adapted using the Bayes approach. The algorithm proposed is compared with other timetabling algorithms using the web-based software. A multi-start algorithm is a simple way to provide the convergence, if the number of uniformly distributed starting points is large. A disadvantage is slow convergence.
Therefore, the first aim of this paper is experimental comparisons of the efficiency of different versions of multi-start algorithms in the optimization of timetables. To obtain representative results, the algorithms should be compatible with the Lithuanian high school practice and flexible enough for adaptation to different high schools.
The second aim is a web-based implementation of these algorithms in a way convenient for high schools. The web-based software is important for evaluation and comparison of algorithms by independent experts, as well, since the efficiency of algorithms depends on subjective parameters specific to each school, so on-line calculations are needed to obtain representative data. It is useful for scientific cooperation and applications to different schools. In addition, the software for evaluating of real timetables is included to compare with the results of optimization.
Journal:Informatica
Volume 11, Issue 1 (2000), pp. 49–64
Abstract
Growing popularity of the mobile code requires to consider various aspects related to its security. In the aviation industry there is a case when additional information needs to be delivered to the pilot by uploading it from the ground station. It creates a need for a platform-independent solution and it raises a problem of the mobile code security as well. Organization of the security in the Base System (similar to extranets) as well as the security issues of the mobile code (or safelets for use in the aircrafts) delivered to the Remote Platform are discussed in the paper. Safelet implementation technologies and issues of code effectiveness and safety itself are discussed with Java and Juice/Oberon technologies been compared.