Geckos with adhesive toe pads rapidly climb even smooth vertical surfaces. We challenged geckos (Hemidactylus garnotii) to climb up a smooth vertical track that contained a force platform. Geckos climbed vertically at up to 77 cm s(-1) with a stride frequency of 15 Hz using a trotting gait. During each step, whole body fore-aft, lateral and normal forces all decreased to zero when the animal at...

We investigate the error surface of the XOR problem for a 2-2-1 network with sigmoid transfer functions. It is proved that all stationary points with finite weights are saddle points with positive error or absolute minima with error zero. So, for finite weights no local minima occur. The proof results from a careful analysis of the Taylor series expansion around the stationary points. For some ...

In this paper we develop a new technique that yields infinitely many surface bundles with non-zero signature. © 2007 Elsevier B.V. All rights reserved.

Rectangular lattices of microgels at interfaces self-assemble near zero surface pressure due to attractive quadrupolar capillary interactions and steric repulsion. They can be used for soft colloidal lithography.

We prove that if f is an orientation-preserving homeomorphism of a closed orientable surface M whose singular set Σ(f) is totally disconnected, then f is topologically conjugate to a conformal transformation.

The problem of determining the free surface due to a jet against a vertical plate is considered. The classical problem of free streamline flow of an ideal fluid has been studied by many authors [1− 4] . The first work in this type of problem is characterized by the use of the Schwartz-Christoffel formula. The latter can treat the flows of border, which combines rectilinear paroies and a free su...

in this paper, we generalize a theorem of shao [12] by assuming that is a sequence of linear negatively dependent random variables. also, we extend some theorems of chao [6] and thrum [14]. it is shown by an elementary method that for linear negatively dependent identically random variables with finite -th absolute moment the weighted sums converge to zero as where and is an array of real numbe...

This paper proposes a novel approach to early determination of zero-quantized 8× 8 discrete cosine transform (DCT) coefficients for fast video encoding. First, with the dynamic range analysis of DCT coefficients at different frequency positions, several sufficient conditions are derived to early determine whether a prediction error block (8× 8) is an all-zero or a partial-zero block, i.e., the ...

in this paper, we present an edge detection method based on wavelet transform and hessian matrix of image at each pixel. many methods which based on wavelet transform, use wavelet transform to approximate the gradient of image and detect edges by searching the modulus maximum of gradient vectors. in our scheme, we use wavelet transform to approximate hessian matrix of image at each pixel, too. ...