As the two dimensional version of the functional wavefront manipulation metamaterial, metasurface has become a research hot spot for engineering the wavefront at will with a subwavelength thickness. The wave scattered by the gradient metasurface, which is composed by the periodic supercells, is governed by the generalized Snell's law. However, the critical angle that derived from the generalize...

We present a generalization of Meyer's theory of the trilinear coupling between the smectic layers, the tilt angle of the optical axis with respect to the layer normal and the electric polarization which accounts for the spontaneous ferroelectricity in smectic C* liquid crystals. This coupling allows for the description of the electroclinic effect, I-ethe appearance of a polarization and a tilt...

This paper presents a new approach for the protection of Thyristor-Controlled Series Compensator (TCSC) line using Support Vector Machine (SVM). One SVM is trained for fault classification and another for section identification. This method use three phase current measurement that results in better speed and accuracy than other SVM based methods which used single phase current measurement. This...

Medical image segmentation is one of the key technologies in computer aided diagnosis. Due to the complexity and diversity of medical images, the wavelet multi-scale analysis is introduced into GVF (gradient vector flow) snake model. The modulus values of each scale and phase angle values are calculated using wavelet transform, and the local maximum points of modulus values, which are the conto...

We have performed scanning x-ray nanobeam diffraction experiments on single cells of the amoeba Dictyostelium discoideum. Cells have been investigated in 1), freeze-dried, 2), frozen-hydrated (vitrified), and 3), initially alive states. The spatially resolved small-angle x-ray scattering signal shows characteristic streaklike patterns in reciprocal space, which we attribute to fiber bundles of ...

the prediction of the joint angle position, especially during tremor bursts, can be useful for detecting, tracking, and forecasting tremors. thus, this research proposes a new model for predicting the wrist joint position during rhythmic bursts and inter‑burst intervals. since a tremor is an approximately rhythmic and roughly sinusoidal movement, neural oscillators have been selected to underli...

To evaluate their phase image characteristics, 61 patients with varying left ventricular contraction abnormalities were studied. In 16 normal patients, the left ventricular phase image revealed a homogeneous pattern, a narrow bell-shaped histogram and an orderly spatial progression of phase angle (phi). In 16 patients with segmental abnormalities, the left ventricular phase image showed a regio...

We present a perturbation theory for studying the instabilities of non-axisymmetric gaseous discs. We perturb the dynamical equations of self-gravitating fluids in the vicinity of a non-axisymmetric equilibrium, and expand the perturbed physical quantities in terms of a complete basis set and a small non-axisymmetry parameter ǫ. We then derive a linear eigenvalue problem in matrix form, and det...

We consider the diiusion problem for the standard map by examining the distribution functions both in the angle and the action. For small perturbations the diiusion occurs only in the presence of an external noise of small amplitude and it is well described by a local isochronous approximation which allows to compute analytically the diiusion coeecient. The angle diiusion is very fast since the...