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991.
992.
This paper introduces a system for mosaicking sequences of soccer images in a panoramic view for soccer game analysis. The continuous mosaic images of the soccer ground field allow the user to view a wide picture of the players’ actions. The initial component of our algorithm automatically detects and traces the players and some lines. The next component of our algorithm finds the parameters of the captured image coordinates and transforms them into ground model coordinates for automatic soccer game analysis. The results of our experimentations indicate that the proposed system offers a promising method for segmenting, mosaicking, and analyzing soccer image sequences.  相似文献   
993.
The lower critical solution temperature (LCST) properties and hydrolytic behaviour of thermosensitive biodegradable polyphosphazenes with monomethoxy‐poly(ethylene glycol), glycine ethyl ester and depsipeptide ethyl esters substituents have been studied. All the polymers synthesized show LCST properties. The LCSTs of the polymers are affected by the composition of the polymers and increase with the degradation of the polymers in aqueous solution. The higher content of depsipeptide ethyl esters in the polymers accelerates the LCST change and the degradation of the polymers in aqueous solution. Most polymers synthesized have half‐lives of less than 10 days in neutral solution. © 2002 Society of Chemical Industry  相似文献   
994.
This paper presents a novel approach for navigation of cleaning robots in an unknown workspace. To do so, we propose a new map representation method as well as a complete coverage navigation method. First, we discuss a triangular cell map representation which makes the cleaning robot navigate with a shorter path and increased flexibility than a rectangular cell map representation. Then, we propose the complete coverage navigation and map construction methods which enable the cleaning robot to navigate the complete workspace without complete information about the environment. Finally, we evaluate the performance of our proposed triangular cell map via the existing distance-transform-based path-planning method comparing it to that of the rectangular cell map. Also, we verify the effectiveness of the proposed methods through computer simulations.  相似文献   
995.
A combined biological denitrification and sulfate precipitation process was developed to treat and reuse the spent brine produced by a nitrate exchange system. Although the spent brine contained a relatively high salt concentration, more than 80% of NO3(-)-N fed into the denitrification reactors was removed at a nitrate-N loading rate of 2.2 g NO3(-)-N/l x day, regardless of the presence or absence of sulfate up to 8,000 mg/l. Sulfate present in the spent brine was successfully removed by the addition of BaCl2 and the settling velocity of BaSO4 suspension was remarkably enhanced by FeCl3 coagulation. Since most of the chloride consumed in regenerating the exhausted resins was replaced during chemical treatment with BaCl2 and FeCl3, it was possible to reuse the treated spent brine as a regenerant after compensating for the small amount of unreplaced NaCl.  相似文献   
996.
Silicon nitride ceramics seeded with 3 wt%β-Si3N4 whiskers of two different sizes were prepared by a modified tape casting and gas pressure sintering. The fine whiskers had a higher aspect ratio than the coarse whiskers. Quantitative texture analysis including calculation of the orientation distribution function (ODF) was used for obtaining the degrees of preferred orientation of sintered samples. The maximum multiples of random distribution (mrd) values of samples seeded with the fine and coarse whiskers were large, greater than 15 and 9, respectively. Meanwhile, the mrd value of a sample seeded with fine whiskers was only 9 when it was prepared by conventional tape casting. The microstructures and the XRD data revealed that the well-aligned whiskers grew significantly after sintering and dominated the texture. Differences among the degrees of preferred orientation of the samples were explained using Jeffrey's model on rotation of elliptical particles carried by a viscous fluid.  相似文献   
997.
To determine the optimum method of producing TiAl intermetallic compounds with an oriented lamellar microstructure the authors applied reactive diffusion and high-temperature deformation in a two-phase state on Ti-43 mol.%Al and Ti-46 mol.%Al. The reactive diffusion process produces an α single-phase state with orientations that reflect the texture of the starting titanium foils; the high-temperature deformation aims to rotate the lamellar interface by means of preferential activation of the crystal slip systems that are parallel to the interface. The reactive diffusion process can effectively control the texture in an α single-phase state, though many voids are formed at the initial stages of reactive diffusion. Furthermore, after the heating process for the construction of the lamellar microstructure, uniaxial compression at 1323 K is quite effective for ensuring that the lamellar interface is rotated parallel to the compression plane. Finally, the deformation causes about one half of all the lamellae to be arranged within 20 degrees of the compression plane.  相似文献   
998.
The mechanism of enhancement of the red emission efficiency from CaTiO3:Pr3+ thin film by Al addition has been investigated. Al-ions have been attracting interest as a sensitizer to improve the luminescent efficiency of phosphors. Also, influence of Al-doping on the crystallization, surface morphology and luminescent properties of CaTiO3:Pr3+ thin films have been discussed. CaTiO3:Pr3+ and Al-doped CaTiO3:Pr3+ films were grown using pulsed laser deposition technique on Al2O3 (0001) substrates under different substrate temperatures and oxygen pressures. The crystalline phase and surface morphology of the films were very dependent on the oxygen pressure and substrate temperature and they affected the luminescent brightness of the films. The crystalline structure and microstructure of these films have been characterized by X-ray diffraction and electron microscopy and their luminescent properties have been evaluated at room temperature using a luminescence spectrometer and excitation by a broadband incoherent ultraviolet light source with a dominant excitation wavelength of 325 nm. In particular, the incorporation of Al3+ ions into CaTiO3 lattice could induce a remarkable increase of photoluminescence. The enhancement of luminescence for Al-doped films may result not only from the improved crystallinity but also from the reduced internal reflections caused by rougher surfaces. Also, the luminescent intensity and surface roughness of the films exhibited similar behavior as a function of oxygen pressure.  相似文献   
999.
1000.
Cycloadditive reaction of fullerene[C60] with various 2'-azidoethyl per-O-acetyl glycopyranoside of D-mannose, D-galactose, D-glucose, D-xylose and D-maltose, respectively gave the glycosyl fullerene[C60] derivatives 2a-2e such as alpha-D-mannosyl fullerene[C60] under ultrasonication. Based on analyses using 1H- and 13C-NMR, UV-vis, FT-IR, and FAB-MS spectroscopies of the glycosyl fullerene[C60] derivatives, the products were composed of a mixture of [5,6]- and [6,6]-junction isomers which were predominantly the closed [5,6]-junction isomer.  相似文献   
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