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Purpose -The purpose of this paper is to extract features from vibration signals measured from induction motors subjected to accelerated aging of bearings by fluting tests. Design/methodology/approach -Aging tests were performed according to IEEE test procedures. The data acquisition involved the measurement of vibration signals using accelerometers that were installed on the bearings and on the motor casing. In this application, only two accelerometers, which were placed near the process end of the motor bearing, are used for data analysis and feature extraction studies. After the data collection, information from the two sensors was combined using simple sensor fusion method under the linearity conditions, and then spectral analysis and time-scale analysis were performed. The fused vibration signal is decomposed into several scales using continuous wavelet transform (CWT) and its first scale is used to indicate the bearing degradation. Findings -Bearing damage characterization was determined between 2-4 kHz and some specific frequencies were calculated as harmonics of the bearing characteristic frequencies.Research limitations/implications -The bearing damage characteristics used in this study is occurred by the experimental study. In terms of the methodology, the use of the CWT shows the fault characteristics from the initial case. Practical implications -The experimental study and data acquisition are based on the accelerated aging of the motor bearings. Hence, the real aging is represented by the accelerated one. But, this situation reflects same properties of the aging occurred in industrial environments. The methodology is also applicable to the hardware application. Originality/value -There are two important aspects of this research: the experimental study and the application of CWT to get the potential defects, which will appear as a failure in future, from the healthy case of the motor bearings.

A detailed karyotype analysis was developed for Pistacia vera L. grown in Turkey. In vitro roots obtained from mature seeds were used as plant material. The chromosome number of P. vera L. was found to be 2n = 30 at c-metaphase of mitosis cell investigated for all of the materials. Centromere type of all chromosomes were determinated as median, submedian, subtelocentric, telocentric and total lengths of chromosome pairs were found between 35.4 and 5.97 microm. An idiogram was constructed from the average chromosome length, arm ratio and centomere type for each of the chromosome pairs.