Specific parameters comparison of synchronous reluctance electric drives
The article presents the principles of comparison of different types of synchronous contactless electric drives. The mathematical description of the system is given for comparison. It is shown that classical unregulated synchronous electric drives are inferior to induction electric drives by 30–40%. It is caused by both a decrease in excitation and a decrease in the limiting load angle according to the conditions of static stability. The phase current of electric drives with FRRM has a rectangular shape which allows one to significantly improve the weight and dimensions. In this case, the electric drive with FRRM due to the compensation of the armature transverse response allows improving the system characteristics, so that the induction motor is 10–15% less than the FRRM.
A method of calculating the thermal state of an electric machine using three-dimensional numerical simulation programs
In this article, a procedure for numerical simulation of the temperature of electrical machine components with a combined cooling system is considered: by means of flowing cooling, part of the external surface of a motor housing is cooled with water and the internal area of the electrical machine is cooled with air. A comparison of results of simulation by the provided calculation procedure with the experimental data is given.
Automatic classification of TV news articles based on telop character recognition
The purpose of this study is to develop a multimedia database system for TV news video data. TV news video data consist of speech, characters and images. In this study, telop characters are recognized and given to the news articles as indices for classification. At first, telop frames which include telop characters are detected and then the telop characters are extracted and recognized. Through morphological analysis of the recognized telop characters, keywords are extracted which consist of more than two characters. Their keywords are used as indices to classify the TV news articles. We carried out experiments for 30 days of NHK 5 minutes news and obtained 95.4% telop character extraction rate, 81.4% character recognition rate and 83.8% article classification rate. We improved the article classification rate by 43.4% through character recognition improvement from 44.1% to 81.4%.