An efficient modification by Douglas and Kim of the usual alternating directions method reduces the splitting error from O(k2) to O(k3) in time step k. We prove convergence of this modified alternating directions procedure, for the usual non-mixed Galerkin finite element and finite difference cases, under the restriction that k/h2 is sufficiently small, where h is the grid spacing. This improve...

We consider a bilinear reduced-strain finite element of the MITC family for a shallow Reissner-Naghdi type shell. We estimate the consistency error of the element in both membraneand bending-dominated states of deformation. We prove that in the membrane-dominated case, under severe assumptions on the domain, the finite element mesh and the regularity of the solution, an error bound O(h + t−1h1+...

The Earth will require sustainable electricity sources equivalent to 3 to 5 times the commercial power presently produced by 2050. Solar Power Satellite (SPS) is one option for meeting the huge future energy demand. SPS can send enormous amounts of power to the Earth as the form of microwave (MW). A highly efficient microwave power transmission (MPT) system is needed for SPS. A critical goal of...

For acoustic arrays (microphones or loudspeakers) the main beam width of the radiation pattern is determined by the spacing between the elements in terms of the wavelength. Thus the beam pattern depends on the frequency. It is demonstrated that by controlling the spacing and the frequency response of a pair of superposed arrays, constant directivity of the main beam lobe over a wide frequency r...

Vibratory roughness perception occurs when people feel a surface with a rigid probe. Accordingly, perceived roughness should reflect probe and surface geometry, exploratory speed, and force. Experiments 1 and 2 compared magnitude estimation of roughness with the bare finger and two types of probes, one designed to eliminate force moments, under the subject's active control. Experiments 3 and 4 ...

In this paper, we propose a technique based on two evolutionary algorithms simulated annealing and particle swarm optimization to design a linear array of half wavelength long parallel dipole antennas that will generate a pencil beam in the horizontal plane with minimum standing wave ratio (SWR) and fixed side lobe level (SLL). Dynamic range ratio of current amplitude distribution is kept at a ...

The problem of direction-of-arrival (DOA) estimation is investigated for co-prime array, where the co-prime array consists of two uniform sparse linear subarrays with extended inter-element spacing. For each sparse subarray, true DOAs are mapped into several equivalent angles impinging on the traditional uniform linear array with half-wavelength spacing. Then, by applying the estimation of sign...

We studied spatial integration at low contrasts by testing the detection thresholds of multi Gabor element displays, examining connguration parameters such as orientation uniformity, contour smoothness, continuity, spacing and relative phase. We nd that detectability depends on stimulus geometry and is constrained by collinearity and proximity spatial relations. For a \coherent" connguration (e...

A new stiffened composite pipe pile was developed for improving the foundation of reclaimed ground in ocean engineering. To study bearing capacity group, a combination field test and finite element method used. Firstly, tests were performed on proposed single pile. The model verified by comparing numerical simulation results with results. load transfer mechanism from core to cemented soil surro...

Long-term memory formation is sensitive to the pattern of training sessions. Training distributed over time (spaced training) is superior at generating long-term memories than training presented with little or no rest interval (massed training). This spacing effect was observed in a range of organisms from invertebrates to humans. In the present paper, we discuss the evidence supporting cyclic-...