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Sasho Andonov, Marija Cundeva-Blajer
Some considerations about choosing a method for Tcal

The global trends in testing, diagnostics and inspections in manufacturing industry are strongly connected with development and implementation of Industry 4.0 framework. Two years ago, in the scope of initiative Metrology for Industry 4.0, the general idea for Touchless Calibration (TCal) was presented as a method for remote calibration of instruments in manufacturing industry. By implementing the TCal, instead sending the instruments, the companies will send only the Sensor/Transducer to the laboratory. Before that, in manufacturing premises they will provide Relative calibration. It is actually “pairing” (with other words: providing a ”mirror image”) of the Sensor/Transducer and Sensor/Actuators, without having the particular expensive standard (etalon). The method of transforming calibration data is actually determining the types and characteristics of Sensor/Transducer and Sensor/Actuators. Choosing a proper method, means not to increase the Type B uncertainties to the values which are comparable to the classical calibration. In this paper, authors will try to present some considerations regarding choosing a method based on transformation of calibration data into Time/Frequency which can be generated with extremely small uncertainties.

José Luis Prieto Calviño
Ambidexterity: Dimensions for a new scenario

The effects of the VUCA world (stands for Volatility, Uncertainty, Complexity, Ambiguity) affect all kind of organizations and sectors. So, those related to Testing, Inspection, Certification cannot be oblivious. They face the enormous disadvantage of having remained focused on their technical competence having forgotten the importance of management one and its related aspects. The new editions of the international standards of the ISO 17000 series, revised under the High Level Structure (HLS) of ISO Directives Part One, and in particular, the International Standard ISO/IEC 17025:2017 depicts a global approach to objectives and processes. So new challenges also appear in the horizon for sustainability in TIC organizations, especially oriented towards their organizational/managerial aspects where their staff must be focused on. Innovation-driven organizations will be their wide umbrella and a necessary evolution to achieve it is moving through two dimensions such as exploration and exploitation. When it is talking about ambidexterity, or its adjective ambidextrous, one is referring to the link between these two dimensions. This paper introduces the vision chosen from a metrology center such as LOMG to select one combination of exploration and exploitation that allows to face the new scenario with solidity and ensure its sustanaibility and this, through the consolidation of its minimum-viable innovation system (MVIS) which refers to the essential blocks to move to a business-oriented organization.

M. Caruso, A. O. Di Tommaso, R. Miceli, C. Spataro, F. Viola
Experimental Investigation on High-Efficiency Control Algorithms for Three-phase Induction Motors

This paper presents an experimental investigation regarding the power losses variations occurring in three-phase induction motors (IMs) as a function of the magnetization level of the machine. More in detail, the power losses identification is obtained by changing in real-time the working operating conditions of the IM drive and the IM reference flux. The sets of measurements are carried out by setting up a test bench and the obtained results confirm that the power losses occurring in induction motors can be minimized by adequately setting the direct axis current component for each IM working condition. This research represents the starting point for the conception of advanced real-time loss model control algorithms capable of enhancing the efficiency of the IM drive.

Andrea Mariscotti
Comparison of normative limits for electromagnetic emissions of electric machines and drives to use in different applications

Electric machines and power drives of various sizes and ratings are fundamental elements in many applications, such as electric appliances, electric propulsion, medical systems, all with specific limits of electromagnetic emissions, different from those of the original EMC product standards. As compliance should be assessed and guaranteed during design and procurement, this work compares the conducted and radiated emission limits and discusses the variability of results for the respective test setups and measurement methods, including the most relevant source of uncertainty.

Giuseppe Marsala, Carmelo Lodato, Giovanni Tinè
Identification of Equivalent Circuit of Transformer Insulation Parameters Assisted by Constrained GAandPSO Algorithms

Power transformer is a very valuable device of electrical transmission and distribution networks. The life of a power transformer mainly depends on the insulation system conditions. A nondestructive method used for monitoring this system is the Recovery Voltage Measurement (RVM), which allows estimating the polarization spectrum. Mathematical models of this spectrum are used to better understand the physical insulation properties in response to moisture and aging. These models are often used to identify the equivalent circuit of the insulation system. The parameters estimation of this circuit can be performed in different stages of the life of the transformer by RVM measured results. In this paper, the authors present two constrained optimization methods based on the heuristic algorithms GA and PSO to solve the parameter estimation problem. The performances of the two different approaches are compared.

M. Caruso, A.O. Di Tommaso, G. Lisciandrello, Rosario Miceli, C. Nevoloso, C. Spataro
An Accurate Measurement Procedure of Power Losses Variations in Electrical Drives

This paper presents a general procedure for the accurate measurement of power losses variations in electrical drives. More specifically, the paper addresses the issue related to the efficiency comparison of electrical drive controlled with different control algorithms. This procedure is applied to a permanent magnet synchronous motor drive, assessing its power losses by means of two different measurement systems, each one characterized by different accuracy and cost. The comparison between these two systems is carried out for different working conditions in terms of load, speed and magnetization in order to demonstrate that the power losses variations can be accurately measured even with not expensive instrumentation.

Petar Sekulic, Paola Regina, Luana Spadafina, Giuseppe Dentamaro, Alessandro Porcelli, Cristiano Bove, Slavko Kovacevic, Mirko Kalezic
Real-time flood prediction using Recurrent Neural Networks and Random Forest

Floods are one of the most destructive natural disasters as they cause severe material damage and often the loss of human life. Predicting a flood is a challenging task and recent progress in this field was brought by machine learning (ML) models. This paper aims to discover a dependency between spatial and temporal data patterns about the ground and weather that will subsequently lead to the floods. Taking into account features deriving from remote sensing images and weather stations, the proposed algorithm aims to predict whether the flood will happen or not by using Recurrent Neural Networks and Random Forests methods. The algorithm could be considered as a starting point of the research related to prediction of other natural disasters, such as landslides, heavy rainfall, droughts, weather forecasting, etc. The future direction of research aims at improving the accuracy of the algorithm by employing a broader and more structured data set built from validated sources.

Klaus Schilling, Andreas Nüchter
Formations of Small Satellites to Realize Sensor Networks for Earth Observation

At the level of small satellites with a mass of a few kilograms all capabilities of self-organizing sensor networks for Earth observation can be realized. Photogrammetry methods enable sensor data fusion to generate 3-dimensional images of a target area. Here appropriate satellite position information in combination with attitude determination and control provides precision pointing accuracies to generate suitable input for subsequent data processing. This way, on small satellites efficient methods for distributed sensor systems in orbit can be implemented.

Antonino D Alessandro, Giovanni Vitale
KRONOS: a low-cost data-logger for seismological applications

Modern seismology required high resolution, multichannel data-logger able to convert from analog to digital the signals acquired by multi-components broadband seismic sensors. Due to the high performance required, the high level of specialization and customization, and the limited market, a datalogger for seismological purposes is generally very expensive. In this paper we present a new 24 bit, 8 channels, 0.6 μV resolution data-logger called KRONOS, specifically designed for seismological applications and extensive use in seismic monitoring network. Project specifications are defined and laboratory test performed to determine the real resolution of the data-logger. The depth of knowledge of our data-logger performance, can allow us to configure it as best as possible as function of the input sensors, time to time, deciding the best compromise between sampling frequency and resolution as number of bits.

Ovidiu Bejenaru, Catalin Lazarescu, Marius-Vasile Ursachianu, Alexandru Salceanu
Multilayer Case Influence upon SAR Evaluation

The nowadays problem of human exposure to different types of electromagnetic field sources is a challenging one and should be considered an up to date issue due to actual trends, growth and progress of mobile communications technology. We have developed an experimental study over the measured values of specific absorption rate (SAR) for a new generation smartphone device, (frequencies in the range GSM-900 and GSM-1800), using a SATIMOCOMOSAR dosimetry system, provided by LICETER laboratory of ANCOM Romania. The measured SAR values have been compared (for the same exposure scenarios) with those obtained in the case when the mobile phone is protected by a multilayer case. Supplementary, a comparison of the SAR values obtained by direct measurements with those from international and local standards has been also done. Conclusions have been drawn for considered exposure scenarios cases.

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