Research in recent years has supported the hypothesis that many properties of the electroencephalogram (EEG) are specific to an individual. In this study, the intra- and inter-individual variations of sleep EEG signals were investigated. This was carried out by analyzing the stability of the average EEG spectra individually computed for the Rechtschaffen and Kales (RK) sleep stages. Six EEG cha...

A Markov chain model has been proposed as a mechanism that generates human sleep stages. A method for estimating the parameters of the model, i.e., the transition probabilities (rates) between sleep stages, has been introduced and applied to 95 hypnograms taken from 23 subjects. The rates characterize interindividual differences and nightly variations of the sleep mechanism, related to sleep-on...

We consider the homogenization of nonlinear random parabolic operators. Depending on the ratio between time and spatial scales different homogenization regimes are studied and the homogenization procedure is carried out. The parameter dependent auxiliary problem is investigated and used in the construction of the homogenized operator.

Aalto University, P.O. Box 11000, FI-00076 Aalto www.aalto.fi Author Jiaran Qi Name of the doctoral dissertation Dispersion of dielectric composites: quasi-dynamic characterizations and applications Publisher School of Electrical Engineering Unit Department of Radio Science and Engineering Series Aalto University publication series DOCTORAL DISSERTATIONS 61/2011 Field of research Electromagneti...

We examine homogenization methods applied to sharp-interface and diffuse-interface models for gravity-driven flow in heterogeneous porous media. Our work specifically examines a matrix of models that includes (1) a variable media, diffuse-interface model, (2) a variable media, sharp-interface model, (3) a homogenized media, diffuse-interface model and (4) a homogenized media, sharp-interface mo...

In this paper we highlight how the Fonseca and Müller blow-up technique is particularly well suited for homogenization problems. As examples we give a simple proof of the nonlinear homogenization theorem for integral functionals and we prove a homogenization theorem for sets of finite perimeter.

Homogenization of electromagnetic periodic composites is treated as a two-scale problem and solved by approximating the fields on both scales with eigenmodes that satisfy Maxwell's equations and boundary conditions as accurately as possible. Built into this homogenization methodology is an error indicator whose value characterizes the accuracy of homogenization. The proposed theory allows one t...

Homogenization of duplicated genes is an important factor for gene family evolution. In the previous study, we developed a method, named 4-2-4 here, to detect partial homogenization with high sensitivity and high specificity using quartets. A quartet is a set of four genes generated by a duplication event and the subsequent speciation of two closely related species. We searched the human and ma...

the chemical composition and uniform distribution of alloying elements in the matrix of austempered ductile irons (adis) have significant influences on their properties, e.g. segregation of the alloying elements have detrimental effects on the mechanical properties of these materials. unlike previous studies, the homogenization treatment via partial melting was used in this study in order to re...