Cold protective clothing was studied in 2 European Union projects. The objectives were (a) to examine different insulation calculation methods as measured on a manikin (serial or parallel), for the prediction of cold stress (IREQ); (b) to consider the effects of cold protective clothing on metabolic rate; (c) to evaluate the movement and wind correction of clothing insulation values. Tests were...

Ester-based insulation fluids are being increasingly used in high-voltage insulation systems. The reasons are the advantages in the area of ecological compatibility and resource-saving provision. The intention to use ester-based insulation fluids in high voltage direct current (HVDC) equipment is new. The major challenge in designing the HVDC insulation system is, that the systems do not only e...

Motivated by a need within the aerospace industry to detect and characterize degradation in the insulation of onboard wires, this thesis reports testing of several extant methods and development of novel capacitive sensors. The work focuses on measuring the electrical parameters resistance and capacitance that are directly related to the material parameters conductivity and permittivity, respec...

Standard practice in response surface methodology performs factor screening and response surface exploration sequentially, using different designs. A novel approach is proposed to achieve the two objectives on the same experiment, based on one design. Running a uni-stage experiment has the advantages of saving experimentation time and run size. The approach is based on a two-stage analysis that...

in this study, the effect of wall orientation on the optimum insulation position in the wall from different perspectives is studied numerically. using crank- nicolson one dimensional transient heat conduction equation is solved for the wall with convection boundary conditions. outdoor temperature is considered as a periodic function of time. since natural night ventilation is used in the buildi...

polysulfide resins,with trade name of  g4 and g112, with short and long chain lengths respectively, were used as reactive modifiers to toughen epoxy resin. the effects of molecular weights of g4 and g112 on impact resistance, dielectric constant, thermal conductivity as well as decomposition  heat and adhesion properties of toughened epoxy were investigated. the impact strength and the dielectr...

This paper describes an accelerated ageing experiment of transformer oil/paper insulation with preset moisture levels. These samples were tested with return voltage and polarisation/depolarisation measurements. Molecular weight has also been measured with Gel Permeation Chromatography (GPC). Results suggested the impact of moisture on the ageing of oil/paper insulation. An attempt has been made...

Abstract The surface of epoxy composite material working in DC electric field for a long time is easy to accumulate charge and cause flashover, which seriously reduces its insulation level poses threat the safe operation electrical equipment. In this study, SiO x films were deposited on nano-SiO 2 /ER nanoparticles by atmospheric pressure dielectric barrier discharge plasma vapor deposition tec...

The recording characteristics of the monopolar needle in three dimensions have not been well established. A simple spherical recording territory is commonly assumed with the very tip proposed to have a greater spatial recording sensitivity by some authors. We demonstrate by enlarged physical modeling in a homogeneous volume conductor that the recorded amplitude diminishes more gradually radiall...