University of Windsor

About: University of Windsor is a education organization based out in Windsor, Ontario, Canada. It is known for research contribution in the topics: Population & Argumentation theory. The organization has 10654 authors who have published 22307 publications receiving 435906 citations. The organization is also known as: UWindsor & Assumption University of Windsor.

Chemical changes at the surface of RTV silicone rubber coatings on insulators during dry-band arcing

Abstract: Under wet and contaminated conditions dry band arcing occurs on the surface of HV outdoor insulators coated with room temperature vulcanizing (RTV) silicone rubber. The thermal impact of the arcing on the surface of the RTV causes chemical changes. The gradual loss of hydrophobicity due to dry band arcing is of considerable concern because it results in a reduction of the withstand voltage and subsequent failure of the insulator and power outage. In this study the RTV coatings were subjected simultaneously to salt-fog and electrical stress. Attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy and electron spectroscopy for chemical analysis (ESCA) were then employed to investigate the chemical changes. Possible chemical reactions and processes occurring under dry band arcing are suggested. The results of ATR-FTIR and ESCA indicate the formation of low molecular weight polydimethylsiloxane (PDMS), the reduction in the surface density of CH3 groups and crosslinking of the PDMS backbone chains at the surface. Chemical derivative analysis was also carried out to further elucidate the chemical changes on the surface of RTV coating. >

Stagnation flows of micropolar fluids with strong and weak interactions

Abstract: Plane and axially symmetric flows of a micropolar fluid, in contact with an infinite plate, and tending to potential flow at infinity, with a stagnation point on the plate, are considered Two different boundary conditions for the spin are considered: (a), vanishing spin; and (b), vanishing surface moment The equations of motion are reduced to dimensionless forms which include three dimensionless parameters, and integrated numerically by a Runge—Kutta method Results are presented both in tabular and graphical form, and the effects of the values of the parameters on the flow are discussed

Food Web Structure in Temporally-Forced Ecosystems

Abstract: Temporal variation characterizes many of Earth's ecosystems. Despite this, little is known about how food webs respond to regular variation in time, such as occurs broadly with season. We argue that season, and likely any periodicity, structures food webs along a temporal axis in an analogous way to that previously recognized in space; predators shift their diet as different resource compartments and trophic levels become available through time. These characteristics are likely (i) central to ecosystem function and stability based on theory, and (ii) widespread across ecosystem types based on empirical observations. The temporal food web perspective outlined here could provide new insight into the ecosystem-level consequences of altered abiotic and biotic processes that might accompany globally changing environments.

A linear programming approach to recursive digital filter design with linear phase

Abstract: A technique is presented whereby a class of recursive digital filters can be designed to approximate simultaneously given magnitude and linear phase characteristics. The underlying approach is to linearize the inherently nonlinear approximation problem, and thereby use linear programming to carry out the approximation. The linear phase is specified in terms of a desired constant group delay. Therefore, the constraints of the linear program become a function of desired group delay. Thus the design algorithm consists of carrying out a univariant search within a range of group delay values to obtain a minimum error of approximation. Several examples of design are presented to illustrate the usefulness of the method.