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The energy source is one of the main constraints in many aspects of modern life. This fact is of crucial importance when addressing portable electronic devices operation. Portable devices, which can be considered as a distinctive characteristic of the 20th century last quarter, mostly rely on old battery technology as a source of energy. This fact is true for many autonomous electronic devices and is of vital importance when addressing Wireless Sensor Networks implementation. The most obvious energy source for a Wireless Sensor Network node is a battery. Batteries have nevertheless a number of drawbacks making them the main limitation when implementing these systems. Replacing batteries is therefore an important topic of both academic and industrial scientific work. This paper addresses software related implications of running a Wireless Sensor Network node that uses a complex communication protocol and is running on harvested energy. [ABSTRACT FROM AUTHOR]

Abstract: Most three-phase, squirrel-cage, induction motors (SCIMs) are oversized. In the European Union (EU), the average load factor of SCIMs is slightly lower than 60%. In fact, in some industrial sectors, a large part of SCIMs operates with a load factor as low as 25%. Therefore, since the motor load factor is an average of its load over the operating cycle, it can be said that a large quantity of IMs operates with a load under 60%. In oversized IMs, if the actual load cycle is known, it is possible to properly redesign the original stator winding in order to match the peak efficiency with the maximum or dominant load, by means of a magnetizing flux reduction, ultimately leading to the motor power decrease (i.e., downsizing). Moreover, since the original motor active material quantity is maintained, the iron and copper losses and the magnetic saturation level will be reduced, improving the motor efficiency and power factor. In some cases, it is possible to convert an oversized standard motor into a well-sized high-efficiency motor, particularly if best practice is applied during motor repair/rewinding. Even considering the typical 1% efficiency drop due to poor-quality motor repair/rewinding, the motor efficiency gain after downsizing can still be significant. The motor lifetime can also be extended, which is an environmentally advantageous aspect. In this paper, a short review on optimized redesign of oversized SCIM stator windings is presented. Additionally, a large-scale rewinding-based motor downsizing strategy is proposed and the associated savings potential in the EU is estimated. [Copyright &y& Elsevier]