نشریه محاسبات نرم
سال دوم شماره 1 (پیاپی 3، بها و تابستان 1392)

In this paper a new method for speed control of BLDC motors is proposed. In this method، fractional order PID (FOPID) is used for control of BLDC motor. In order to determine the parameters of FOPID controller imperialist competitive algorithm (ICA) is employed for its high speed and accurate for solve of optimization problems. In order to verify the performance of proposed controller، some simulations have been carried out with different object functions in Simulink environment of MATALB and obtained results have been compared with results of conventional PID. Good performance of proposed controller is validated by results of simulations.

A type-2 fuzzy set (or fuzzy-fuzzy set) is a fuzzy set that has fuzzy membership degrees. Such a set is useful wherein it is difficult to determine the exact membership degrees. A type-2 fuzzy system is robust against uncertainties that occur in fuzzy rules and system parameters. In this paper، first، The history of type-2 fuzzy theory which is developed during 25 recently years briefly is reviewed. Then type-2 fuzzy set and systems briefly are introduced and its basic terminologies are reviewed. Then perceptual computing based on type-2 fuzzy sets and methods of resolving difficulties computing of type-2 fuzzy systems are expressed. Finally، the type-2 fuzzy logic applications briefly are reviewed and conclusions and discussion on its future research fields have been done.

The aim is to automate the process of bug localization in program source code. The cause of program failure could be best determined by comparing and analyzing correct and incorrect execution paths generated by running the instrumented program with different failing and passing test cases. To compare and analysis the execution paths، one approach is clustering the paths according to their similarity. To calculate similarities among execution paths، N-gram models could be created for each individual run. The constructed models are further analyzed using cross entropy to compute the similarities among their corresponding execution paths. By counting elements in each execution path، each element is known as uni-gram، we can compute MLE probabilities to create N-gram models، known as markov models. Then by further analyzing the cross-entropy of sequences in each cluster، a series of fault suspicious locations are identified and finally using majority voting among clusters، faulty locations are reported to the programmer as faulty subpath (s). Our experiments on Siemens benchmark suite show that the proposed method in this paper shows the location of faults with high accuracy.

The Spurt is led to increasing the workload for software engineers in context of producing reliable software. Given the importance of producing high quality software، software engineers created an independent process in cycle of software development that called Software Testing. One of the software testing methods that a lot of researches have been done on it is Mutation Testing. Most of the researches include reducing costs of mutant production and using it in various environments (such as security، web، etc.). What is observed as a gap is little attention to the importance of optimized test case generation in Mutation Testing. The paper intends to show importance of test case generation through a comprehensive review and comparison of conducted researches and prepares a road map for researchers who are interested in the field