An Octagonal Shaped Monopole Antenna for UWB Applications with Band Notch Characteristics

Wireless Personal Communications - This article presents a microstrip-fed octagonal shaped monopole antenna with dual band notched characteristics for UWB applications. Partial ground plane has...     

Design and development of virtual instrument for fault diagnosis in fractal antenna array

This paper deals with the development of a virtual instrument for fault diagnosis in fractal antenna array using Lab‐VIEW software. Faults in antenna array are considered on the basis of the radiation pattern. In this study, theta and gain values of radiation patterns for each fault are used in Lab‐VIEW for curve fitting. An artificial neural network (ANN) has been developed for fitted data points using the Leavenberg Marquard algorithm in MATLAB software and mean square error (MSE) is minimized. The designed ANN model has been embedded in the virtual instrument. The proposed virtual instrument system gets test patterns as input and generates output for several faults present in antenna array. Simulated and measured results of the fractal antenna array are validated experimentally. This virtual instrument model has not been developed for fractal antenna array so far.     

Pre-processing of data coming from a laser-EMAT system for non-destructive testing of steel slabs

Non destructive test systems are increasingly applied in the industrial context for their strong potentialities in improving and standardizing quality control. Especially in the intermediate manufacturing stages, early detection of defects on semi-finished products allow their direction towards later production processes according to their quality, with consequent considerable savings in time, energy, materials and work. However, the raw data coming from non destructive test systems are not always immediately suitable for sophisticated defect detection algorithms, due to noise and disturbances which are unavoidable, especially in harsh operating conditions, such as the ones which are typical of the steelmaking cycle. The paper describes some pre-processing operations which are required in order to exploit the data coming from a non destructive test system. Such a system is based on the joint exploitation of Laser and Electro-Magnetic Acoustic Transducer technologies and is applied to the detection of surface and sub-surface cracks in cold and hot steel slabs.     

Deconvolution of data from the filter difference spectrometer: from hardware to maximum entropy

The deconvolution of data from the filter difference spectrometer as presented as a case study in the evolution of data-analysis techniques in neutron scattering. Starting from the hardware filter difference solution, which lends its name to the instrument, we trace the path through the software solution put forward by Mezei to the present-day use of Maximum Entropy.