The division algebra of real quaternions, as the only noncommutative normed division real algebra up to isomorphism of normed algebras, is of great importance. In this note, first we present a brief introduction to quaternion matrices and quaternion linear algebra. This, among other things, will help us present the counterpart of a theorem of Herman Auerbach in the setting of quaternions. More ...

in this paper, time-domain dynamic analysis of dam - infinite reservoir is studied. a numerical method, discrete singular convolution (dsc), which seems to be efficient and simple, has been used to model the mixed boundary conditions. after a brief introduction, dsc is applied to model the equation of motion of fluid-structure with constant cross section subjected to el-centro (1940) earthquake...

The study of pheromones in non-human animals has a long pedigree. In contrast, the existence of human pheromones is controversial, although at its base this controversy may be largely semantic. Here we summarise the converging evidence from phylogeny, physiology, and behaviour that suggests that the human axilla may have some kind of communicative function, and that axillary secretions can infl...

* Associate Professor Department of Community, Occupational and Family Medicine National University of Singapore Address for Reprints: Dr Chia Kee Seng, Department of Community, Occupational and Family Medicine, National University of Singapore, Lower Kent Ridge Road, Singapore 119260. Introduction In modern medical research, it is rare to limit data analysis to merely two variables: a single e...

This note aims at giving a brief introduction to the field of statistical shape analysis looked at from an image analysis point of view. Basic techniques such as Procrustes analysis, tangent space projection and Principal Component Analysis (PCA) are presented and subsequently demonstrated and discussed in depth through a biometric case study of hands. Prerequisites are limited to basic knowled...