Integrated-optic devices for use in high-voltage substations are reviewed. Specifically, two types of integrated-optic Mach-Zehnder and the integrated-optic Pockels cell are described and compared. A system for monitoring the condition offluid-and-paper insulation systems, such as are used in many current transformers and power transformer bushings, is also described. This condition monitoring ...

Early detection of avalanche breakdown in an embedded planar capacitor dielectric is addressed in this paper. These failures were observed during accelerated temperature and voltage aging of embedded planar capacitors. At the time of avalanche breakdown there was a sharp drop in the value of insulation resistance. There was no trend in the values of insulation resistance before failure, making ...

Power transformers are the most complex, important and critical components of the transition and distribution power systems. Insulation system is the key component of life extension, better availability and higher reliability of a transformer. In order to achieve both decreasing operational cost and reliable service conditionbased maintenance is needed. Monitoring and diagnostic methods and tec...

Membrane-type acoustic metamaterials are well known for low-frequency sound insulation. In this work, by introducing a flexible piezoelectric patch, we propose sound-insulation metamaterials with the ability of energy harvesting from sound waves. The dual functionality of the metamaterial device has been verified by experimental results, which show an over 20 dB sound transmission loss and a ma...

The Rab1-Nielsen formulas are used to make predictions for solar pond operations for four locations situated in different solar insulation zones in Iran. The inputs to the computer program for determining the temperature variation at the bottom of the pond are the total insulation (corrected for cloudiness). ambient temperature, insolating layer thickness, convection layer thickness and load. T...

Temperature, relative humidity and overhygroscopic moisture fields in a sandstone wall provided with interior thermal insulation were calculated in order to assess the hygric performance of the retrofitted wall. Computational simulations showed that during the time period of 10 years which was subject of investigation no overhygroscopic moisture appeared in the analyzed building envelope so tha...

Crosslinked polyethylene (XLPE) has become the globally preferred insulation for power cables, both for distribution and transmission system applications. This insulation system provides cost efficiency in operation and procurement, as well as lower environmental and maintenance requirements when compared to older impregnated paper systems. The purpose of this paper is to outline some of the de...

When insulation fault occurs in the ignition coil partial secondary winding discharges. Random pulses with various amplitudes appear in primary current and secondary voltage waveforms simultaneously. Moreover the secondary voltage may distort if the fault is serious. Traditional methods are difficult to identify the discharge pulses. This paper examines a measure to overcome the shortages of tr...

Background The issue of formaldehyde exposure in homes is long-standing and has been studied over time. Formaldehyde is frequently used in plywood, fiberboard, resins, glues, and several other construction components. In the past, formaldehyde was also used in insulation of many homes. In March of 1982, the U.S. Consumer Product Safety Commission (CPSC) called for a ban on urea foam formaldehyd...

Axonal insulation is of key importance for the proper propagation of action potentials. In Drosophila and other invertebrates, it has recently been demonstrated that septate junctions play an essential role in axonal insulation or blood-brain-barrier formation. Neurexin IV, a molecular component of Drosophila septate junctions, has been shown to be essential for axonal insulation in the PNS in ...