This paper presents an algorithm to estimate the parameters of two closely spaced sinusoids, providing a frequency resolution that is more than 800 times greater than that obtained by using the Discrete Fourier Transform (DFT). The strategy uses a highly optimized grid search approach to accurately estimate frequency, amplitude and phase of both sinusoids, keeping at the same time the computati...

To prevent large error accumulation in multiple image registration considering real-time applications, we propose a new fast global mosaic method using sequential block matching in regularly spaced grid features. We use a specific graph structure called a sequential graph defined in each grid and propose a new shortestpath search algorithm to find exact matchings in a sequential manner. Using a...

using satellite altimetry derived mean sea level (msl), geopotential coefficients in terms of ellipsoidal harmonics from recent satellite gravimetry missions, gravity potential values over a grid consisting of 33,486 points at global sea areas are computed and the mean value of the gravity potential at msl is calculated as a new geoid’s potential value. in this way we have exactly followed the ...

We report a novel grid based Optofluidic Microscope (OFM) method where a closely spaced 2D grid of nanoapertures (diameter = 100 nm, separation = 2.5 mum) provided patterned illumination. We achieved a one-to-one mapping of the light transmissions through the nanoapertures onto a high-speed CCD camera. By optically tweezing a targeted sample across the grid in a controlled fashion and recording...

One of the challenges in personal positioning is the efficient numerical solution of the nonlinear filtering equations resulting from the fusion of different measurement sources. One approach to nonlinear filtering is based on approximating probability density functions with piecewise constant functions. In this work, a moving grid filter is outlined and it is applied to the hybrid local positi...

We present an advanced new sensor, the Greenhouse Gas Monitor (GGM), which will revolutionize the global measurement of greenhouse gas levels. The GGM is an ideal compact, passive instrument for deployment on future-generation small LEO satellites. The Kyoto summit on greenhouse gas and carbon emissions has demonstrated the urgent need for accurate, global monitoring of a range of greenhouse ga...

Planar closed contours are used in number of applications such as optical character recognition (OCR), content based image retrieval (CBIR), medical image processing, etc., for object representation, feature vector extraction and object recognition. Some feature generation techniques, for example Fourier descriptors (FDs), require contours to be represented with 2 number of equally spaced point...

The transition of oligonucleotides from the B to the A conformation has been studied by the use of simple geometric calculations aimed at finding possible hydration sites which could stabilize these conformations. The method involves the classification of equally spaced grid points, surrounding the oligonucleotide, into groups depending on whether a water molecule, so placed, could form single,...

We present a parallel quadtree algorithm that resolves between geometric objects, modeling space between objects rather than the objects themselves. Our quadtree has the property that no cell intersects more than one labeled object. A popular technique for discretizing space is to impose a uniform grid – an approach that is easily parallelizable but often fails because object separation isn’t k...