The paper presents a measurement method for power quality analysis in electrical power systems. The method is the evolution of an iterative procedure already set up by the authors and allows the most relevant disturbances in electrical power systems to be detected, localized and estimated automatically. The detection of the disturbance and its duration are attained by a proper application, on the sampled signal, of the Continuous Wavelet Transform (CWT). Disturbance amplitude is estimated by decomposing, in an optimized way, the signal in frequency subbands by means of the Discrete Time Wavelet Transform (DTWT). The proposed method is characterized by high rejection to noise, introduced by both measurement chain and system under test, and it is designed for an agile disturbance classification. Moreover, it is also conceived for future implementation both in a real-time measurement equipment and in an off-line analysis tool. In the paper firstly the theoretical background is reported and briefly discussed. Then, the proposed method is described in detail. Finally, some case-studies are examined in order to highlight the performance of the method. © 1998 IEEE

In recent years, there has been a strong activity in the so-called precision agriculture, particularly the monitoring aspect, not only to improve productivity, but also to meet demand of a growing population. At a large scale, precise monitoring of cultivated fields is a quite challenging task. Therefore, this paper aims to propose a survey on techniques, applied to precision agriculture monitoring, through the use of drones equipped with multispectral, thermal and visible cameras. For each application, the main limitations are highlighted and the parameters to be considered before to perform a flight are reported.

A and B scan echography does not allow to measure separately the tickness of the three ocular layers, retina, choroid and sclera. This, however, is possible by radiofrequency signals. 48 eyes of normal subjects and 21 eyes of patient suffering from chronic glaucoma with ocular hypertension from 30 to 45 mm Hg were examined. The tickness of the retina and sclera was equal in the two groups, whereas the thickness of the choroid in the glaucomatous eyes showed an increase of 20% as compared with normal eyes.

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