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Health condition monitoring of induction motors is important because of their vital role and wide us in a variety of industries. A stator inter-turn fault (SITF) is considered to be the most common electrical failure according to statistical studies. In this paper, an algorithm for the detection of an SITF is presented. It is based on one of the blind source separation techniques called principal component analysis (PCA). The proposed algorithm uses PCA to discriminate between the faulty components of motor current signatures and motor voltage signatures from other components. The standard deviation of one of the decomposed vectors is used as a statistical SITF criterion. The proposed criterion is robust to non-fault conditions including voltage quality problems and large mechanical load changes as well as harmonic contaminants in the voltage supply. In addition, with a straightforward and low computational burden in the fault detection process, the proposed method is computationally efficient. To evaluate the performance of the proposed method, large numbers of practical and simulation scenarios are considered, and the results confirm the good performance, high degree of accuracy, and good convergence speed of the proposed method.

Today, radicalism ethnocentrism has become a primary source of violent armed conflicts inside the country and in some parts of the world and has entailed an attrition of nation-state's power. On the other hand, ethnic nationalism in some countries has targeted national integrity and the very foundation of the society. This paper seeks to respond to the question: What impacts does this ethnic scatteredness and diversity have on the order and security of the Islamic Republic of Iran? What solutions are there for the national integrity? That which is certain is the existence of various ethnic groups in Iran which have rarely caused conflicts and engagements; from the issue of Turkmen Sahra and Azarbayjan in the early Revolution to the strikes by Kurdish people in May 2010 which are all issues that have been effective on the public order and security of Iran. Therefore, it is necessary for Iran to adopt effective steps in the direction of national integrity while relying on converging components of the Iranian ethnic groups including shared religion, shared land, and also the issue of shared security. Of course, looking upon the 37 year old history of Iran, this demonstrates that the country has made huge progress in this regard. The methodology is descriptive-analytical and by using data and information, some solutions have been offered.