166 resultados para shape conversion


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The increasing use of 3D modeling of Human Face in Face Recognition systems, User Interfaces, Graphics, Gaming and the like has made it an area of active study. Majority of the 3D sensors rely on color coded light projection for 3D estimation. Such systems fail to generate any response in regions covered by Facial Hair (like beard, mustache), and hence generate holes in the model which have to be filled manually later on. We propose the use of wavelet transform based analysis to extract the 3D model of Human Faces from a sinusoidal white light fringe projected image. Our method requires only a single image as input. The method is robust to texture variations on the face due to space-frequency localization property of the wavelet transform. It can generate models to pixel level refinement as the phase is estimated for each pixel by a continuous wavelet transform. In cases of sparse Facial Hair, the shape distortions due to hairs can be filtered out, yielding an estimate for the underlying face. We use a low-pass filtering approach to estimate the face texture from the same image. We demonstrate the method on several Human Faces both with and without Facial Hairs. Unseen views of the face are generated by texture mapping on different rotations of the obtained 3D structure. To the best of our knowledge, this is the first attempt to estimate 3D for Human Faces in presence of Facial hair structures like beard and mustache without generating holes in those areas.

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1S,5R,7R)-(-)-10, 10-Dimethyl-3-ethyl-4-oxa--atricyclo[5.2.1.0(1,5)]dec-2-ene 2 was prepared in 95% yield from (1S)-1-amino-2-exo-hydroxyapocamphane 1. The chiral oxazoline could be alkylated (Lhttp://eprints.iisc.ernet.in/cgi/users/home?screen=EPrint::Edit&eprintid=31175&stage=core#tDA/THF/-78 degrees C/RX, RX = ethyl, n-propyl, n-butyl iodides or benzyl bromide) to 3 in 95% yield and > 95% diastereoselectivity, and the products hydrolysed to (R)-2-methylalkanoic acids 4 (43-47% yield, 93-98% e.e.). (C) 2000 Elsevier Science Ltd. All rights reserved.

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The extremities of chromosomes end in a G-rich single-stranded overhang that has been implicated in the onset of the replicate senescence. The repeated sequence forming a G-overhang is able to adopt a four-stranded DNA structure called G-quadruplex, which is a poor substrate for the enzyme telomerase. Small molecule based ligands that selectively stabilize the telomeric G-quadruplex DNA, induce telomere shortening eventually leading to cell death. Herein, we have investigated the G-quadruplex DNA interaction with two isomeric bisbenzimidazole-based compounds that differ in terms of shape (V-shaped angular vs linear).While the linear isomer induced some stabilization of the intramolecular G-quadruplex structure generated in the presence of Na+ the other, having V-shaped central planar core, caused a dramatic structural alteration of the latter, above a threshold concentration. This transition was evident from the pronounced changes observed in the circular dichroism spectra and from the get mobility shift assa involving the G-quadruples DNA. Notably, this angular isomer could also induce the G-quadruplex formation in the absence of any added cation. The ligand-quadruples complexes were investigated by computational molecular modeling, providing further information on structure-activity relationships. Finally, TRAP (telomerase repeat amplification protocol) experiments demonstrated that the angular isomer is selective toward the inhibition of telomerase activity.

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Preparation of Rb-beta -alumina was realized by the gel-to-crystallite conversion method. Reaction of hydrated aluminum hydroxide gel with RbOH in ethanol medium gave rise to the Rb+-inserted pseudoboehmite precursor under wet chemical conditions. The thermal decomposition of the precursor yielded Rb-beta -alumina. The Rb2O:Al2O3 ratio of monophasic Rb-beta -alumina ranged from 1:10 to 1:22. The extended stability in the compositional range is due to the fact that the conduction planes containing Rb+ and O2- ions can have lower occupancy of Rb+ ions for larger sized alkali ions, permitting the steric separation of the adjoining spinel blocks. High-resolution electron microscopy revealed that the decreasing occupancy of alkali ions in the conduction plane is balanced by changing widths of spinel blocks arising from the shift of tetrahedral Al3+ ions to octahedral sites and an accompanying increase in stacking defects. (C) 2000 Elsevier Science Ltd. All rights reserved.

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A simple technique for the measurement of the beam shape parameters of pulsed lasers, with just a single pulse of the laser is described. It involves the use of several beam dividers inclined at very small angles to the beam axis, reflecting the beam back to a screen or a phosphor placed near the exit of the laser. The reflected images are then photographed by a camera to yield the beam parameters.

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Description of gel-to-crystallite conversion process is made towards the synthesis of nanocrystalline titanates and aluminates. Thermodynamic and kinetic factors governing the conversion of a gel to meta-stable and stable nanocrystalline products(s) are discussed. Correlations between these factors and the preparative conditions employed for the syntheses of titanates and aluminates are arrived at.

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The method of structured programming or program development using a top-down, stepwise refinement technique provides a systematic approach for the development of programs of considerable complexity. The aim of this paper is to present the philosophy of structured programming through a case study of a nonnumeric programming task. The problem of converting a well-formed formula in first-order logic into prenex normal form is considered. The program has been coded in the programming language PASCAL and implemented on a DEC-10 system. The program has about 500 lines of code and comprises 11 procedures.

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The effect of thermal cycling on the load-controlled tension-tension fatigue behavior of a Ni-Ti-Fe shape memory alloy (SMA) at room temperature was studied. Considerable strain accumulation was observed to occur in this alloy under both quasi-static and cyclic loading conditions. Though, in all cases, steady-state is reached within the first 50-100 cycles, the accumulated steady-state strain, epsilon(p.ss), is much smaller in thermally cycled alloy. As a result, the fatigue performance of them was found to be significantly enhanced vis-a-vis the as-solutionized alloy. Furthermore, under load-controlled conditions, the fatigue life of Ni-Ti-Fe alloys was found to be exclusively dependent on epsilon(p.ss). Observations made by profilometry and differential scanning calorimetry (DSC) indicate that the 200-500% enhancement in fatigue life of thermally cycled alloy is due to the homogeneous distribution of the accumulated fatigue strain. (C) 2010 Elsevier B.V. All rights reserved.

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Coordination-driven self-assembly of 1,3,5-benzenetricarboxylate (tma; 1) and oxalato-bridged p-cymeneruthenium(II) building block Ru-2(mu-eta(4)-C2O4)(MeOH)(2)(eta(6)-p-cymene)(2)](O3SCF3)(2) (2) affords an unusual octanuclear incomplete prism Ru-8(eta(6)-p-cymene)(8)(tma)(2)(mu-eta(4)-C2O4)(2)(OMe)(4)](O3SCF3)( 2) (3), which exhibits a remarkable shape-selective binding affinity for neutral phenolic compounds via hydrogen-bonding interactions (p-cymene = p-(PrC6H4Me)-Pr-i). Such a binding was confirmed by single-crystal X-ray diffraction analysis using 1,3,5-trihydroxybenzene as an analyte.

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Ultraviolet radiation has been generated by tangentially phase-matched sum-frequency mixing in biaxial L-arginine phosphate (LAP) crystal for the first time using Nd:YAG output at 1064 nm and Rh 6G dye laser output at 560 nm as the two input sources. Characterization has also been made of such a cheap, biaxial crystal for its possible use in devices for tangentially phase-matched short wavelength generation. If the crystal is of proper cut, thickness and quality so that its maximum capability can be exploited it can replace the potassium dihydrogen phosphate (KDP) group of crystals for various applications.