We show that there is a computable Boolean algebra B and a computably enumerable ideal I of B such that the quotient algebra B=I is of Cantor{Bendixson rank 1 and is not isomorphic to any computable Boolean algebra. This extends a result of L. Feiner and is deduced from Feiner's result even though Feiner's construction yields a Boolean algebra of in nite Cantor{Bendixson rank.

Image restoration has been an active research area. Dierent formulations are eective in high qualityrecovery. Partial Dierential Equations (PDEs) have become an important tool in image processingand analysis. One of the earliest models based on PDEs is Perona-Malik model that is a kindof anisotropic diusion (ANDI) lter. Anisotropic diusion lter has become a valuable tool indierent elds of image...

A novel and eective method based on Haar wavelets and Block Pulse Functions(BPFs) is proposed to solve nonlinear Fredholm integro-dierential equations of fractional order.The operational matrix of Haar wavelets via BPFs is derived and together with Haar waveletoperational matrix of fractional integration are used to transform the mentioned equation to asystem of algebraic equations. Our new met...

The dependence of the e€ective secondary electron yield on the potential distribution and the target materials was investigated by means of electron transport simulation in the sheath with the potential distribution calculated for the di€erent emission characteristics of Be (Zˆ 4), C (Zˆ 6), Mo (Zˆ 42) and W (Zˆ 74) as the target materials. For lower primary energy incidence the e€ective second...

We present a comparison between the di€erent methods reported in the literature to experimentally determine the electron mobility in the channel of a MOSFET. In order to accurately obtain the mobility for use in an I±V model a suitable determination of inversion charge and electric potential is shown to be relevant. Numerical simulation is demonstrated to be a powerful tool to carry out mobilit...

Despite increasing applications of arti®cial neural networks (NNs) to forecasting over the past decade, opinions regarding their contribution are mixed. Evaluating research in this area has been dicult, due to lack of clear criteria. We identi®ed eleven guidelines that could be used in evaluating this literature. Using these, we examined applications of NNs to business forecasting and predicti...