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181.
182.
Text recognition captured in multiple frames by a hand-held video camera is a challenging task because it is possible to capture and recognize a longer line of text while improving the quality of the text image by utilizing the redundancy of the overlapping areas between the frames. For this task, the video frames should be registered, i.e., mosaiced, after compensating for their distortions due to camera shakes. In this paper, a mosaicing-by-recognition technique is proposed where the problems of video mosaicing and text recognition are formulated as a unified optimization problem and solved by a dynamic programming-based optimization algorithm simultaneously and collaboratively. Experimental results indicate that, even if the frames undergo various distortions such as rotation, scaling, translation, and nonlinear speed fluctuation of camera movement, the proposed technique provides fine mosaic image by accurate distortion estimation (around 90% of perfect estimation) and character recognition accuracy (over 95%). 相似文献
183.
Pb(Mg1/3 Nb2/3 )O3 –PbTiO3 (PMN–PT) thin films were prepared by spin coating using aqueous solutions of metal salts containing polyvinylpyrrolidone, where niobium oxide layers and lead—magnesium–titanium oxide layers were laminated on Pt(111)/TiO x /SiO2 /Si(100) substrates and fired at 750° or 800°C. 250 ± 20 nm thick 0.7PMN–0.3PT thin films of a single-phase perovskite could be prepared, and the film fired at 750°C had dielectric constants and dielectric loss of 1900 ± 350 and 0.13 ± 0.03, respectively, exhibiting polarization-electric field hysteresis with a remanent polarization of 5.1 μC/cm2 and a coercive field of 21 kV/cm. 相似文献
184.
K2 O activity in K+ -(α+β)-alumina was determined from emf data of the galvanic cell Pt,O2 ,(α+β)-alumina/K+ -β-alumina/K2 SO4 ,SO2 +SO3 +O2 ,Pt. K2 O activity in the K+ -(α+β)-alumina was expressed by the equation log ak2o (±0.038)=(−18295±120)(K/T)+(0.998±0.110), where 961 K+ -β-alumina are discussed: the standard Gibbs energy of formation of K2 O·11Al2 O3 from K2 O and α-Al2 O3 and from K, O, and Al; the thermodynamic stabilities of K+ -β-alumina in the atmospheres of SOx (x=2, 3) and CO2 ; the equilibrium vapor pressure of potassium over K+ -β-alumina under a constant O2 pressure; and the stability of K+ -β-alumina in the molten Na-K alloy. 相似文献
185.
The activity coefficient of oxygen in liquid tellurium at 753 nd 823 K w s measured by the coulometric titration method employing solid electrolyte. The oxygen was found to obey Henry’s law, and the standard Gibbs energy of solution of oxygen in liquid tellurium for l/2O2 O (1 t. pct) was determined to be: 1 $$\Delta G^O (inTe ) = ---21,840 + 10.3T (cal/g--atom)$$ 2 $$ = ---91,380 + 43.1T (J/g--atom)$$ . The standard Gibbs energy of formation of TeO2 was also determined by using similar electrochemical cell; the result is: 3 $$\Delta G^O (TeO_2 ) = - 79,920 + 46.5T(cal/mol)$$ 4 $$ = - 334,400 + 194.6T(J/mol)$$ The solubility of oxygen in liquid tellurium was calculated from the combination of these two results to be: 5 $$C_S = \exp (6.52 - 9119/T)(at.pct )$$ By comparison of the present results for tellurium with the published values for the other elements, thermodyn mic behavior of oxygen dissolved in liquid elements was discussed and compared with sulfur dissolved in liquid elements. 相似文献
186.
Furukawa J Shinohara Y Kuramoto H Miura Y Shimaoka H Kurogochi M Nakano M Nishimura S 《Analytical chemistry》2008,80(4):1094-1101
Changes in protein glycosylation profoundly affect protein function. To understand these effects of altered protein glycosylation, we urgently need high-throughput technologies to analyze glycan expression and glycan-protein interactions. Methods are not available for amplification of glycans; therefore, highly efficient sample preparation is a major issue. Here we present a novel strategy that allows flexible and sequential incorporation of various functional tags into oligosaccharides derived from biological samples in a practical manner. When combined with a chemoselective glycoblotting platform, our analysis enables us to complete sample preparation (from serum to released, purified, methyl-esterified, and labeled glycans) in 8 h from multiple serum samples (up to 96 samples) using a 96-well microplate format and a standard de-N-glycosylation protocol that requires reductive alkylation and tryptic digestion prior to PNGase F digestion to ensure maximal de-N-glycosylation efficiency. Using this technique, we quantitatively detected more than 120 glycans on human carcinoembryonic antigens for the first time. This approach was further developed to include a streamlined method of purification, chromatographic fractionation, and immobilization onto a solid support for interaction analysis. Since our approach enables rapid, flexible, and highly efficient tag conversion, it will contribute greatly to a variety of glycomic studies. 相似文献
187.
Fabrication and photoactivities of spherical-shaped BiVO4 photocatalysts through solution combustion synthesis method 总被引:3,自引:0,他引:3
Hai-qing Jiang Hiromitsu Endo Hirotaka Natori Masayuki Nagai Koichi Kobayashi 《Journal of the European Ceramic Society》2008,28(15):2955-2962
Spherical-shaped BiVO4 photocatalysts were prepared by the solution combustion synthesis method. The as-prepared photocatalysts were characterized by X-ray diffraction (XRD), nitrogen absorption for the BET specific surface area, field emission scanning electron microscopy (FE-SEM) and ultraviolet–visible diffraction reflection spectroscopy (UV–vis). The BiVO4 crystallites show a monoclinic structure with diameter of about 400–600 nm. UV–vis diffusion absorption spectra indicate that the band gap absorption edge of pure BiVO4 crystallites prepared by the SCS method and the SSR method are 523 nm and 540 nm, corresponding to the band gap energies of 2.45 eV and 2.40 eV, respectively. It is also found that the photocatalytic activity of degradation of methylene blue improves when the molar ratio of fuels to oxidizer is 5. 相似文献
188.
Micelle formation induced by disproportionation was attained for a diblock copolymer containing 2,2,6,6-tetramethylpyperidine-1-oxyl (TEMPO). Poly(4-vinylbenzyloxy-TEMPO)-block-polystyrene (PVTEMPO-b-PSt) showed no self-assembly in 1,4-dioxane, a nonselective solvent. Light scattering studies demonstrated that the copolymer self-assembled into micelles in this solvent with the addition of hydrochloric acid (HCl). The hydrodynamic diameter of the copolymer was estimated to be ca. 55 nm based on the cumulant analysis of the complete micellization. A UV analysis confirmed that the micellizarion proceeded through the disproportionation of the TEMPO into the oxoaminium chloride and the hydroxylamine by the reaction with HCl, because the absorption based on the oxoaminium chloride increased with an increase in the amount of HCl. ESR verified that the radical concentration of the TEMPO decreased with an increase in the HCl. Before the addition of HCl, the PVTEMPO-b-PSt copolymer showed broad signals based on the random orientation. As the amount of HCl increased, the broad signals changed to the typical triplet of TEMPO, accompanied by a decrease in the signal intensity. The g values had a negligible change throughout the micellization. Finally, 40% of the TEMPO remained unreacted when the micellization was completed. The micellization prevented the dispropotionation of the TEMPO, because the PVTEMPO blocks formed the micellar cores which were covered with the micellar coronas of the PSt blocks. TEM observations demonstrated that PVTEMPO-b-PSt formed spherical micelles through the dispropotionation-induced micellization. 相似文献
189.
Hiromitsu Taniguchi Hitoshi Sugimoto Shigeru Yokoyama 《Electrical Engineering in Japan》1997,119(1):17-23
In order to clarify the cause of lightning outages of a distribution line, simultaneous observation of lightning discharge channels and types of damage on distribution lines were carried out with still cameras from July 1993 through July 1995. High-voltage lines located in the observation area did not suffer from induced voltages due to indirect lightning strikes, even if such lightning strikes were nearby. One instance of a direct lightning strike on a distribution line was observed. The striking point was the span center of the overhead ground wire, and only a transformer fuse was blown on the high-voltage line. Damage to surge arresters was observed in the case of a lightning strike on a building located near a distribution line. The cause is thought to have been lightning current which flowed into the nearby distribution line through the damaged arresters. © 1997 Scripta Technica, Inc. Electr Eng Jpn 119(1): 17–23, 1997 相似文献
190.
Michihiro Uchiumi Hiromitsu Hayashi Kiyotaka Ueda Katsunori Muraoka Fumihiro Kinoshita Masanori Akazaki Toshikatsu Tanaka Chikahisa Honda 《Electrical Engineering in Japan》2001,134(2):11-18
Negative discharge induction experiments were performed with a rod‐to‐rod electrode configuration having a gap length of 0.8 m using a high‐power XeCl excimer laser of maximum output energy of 2 J/pulse and an impulse generator of maximum voltage of 1.2 MV. Development of a leader in the laser‐ionized plasma channel was observed by using an image converter camera. When an XeCl excimer laser is applied at a carefully controlled instant, the guiding effect for an impulse discharge is optimized. Three main results were obtained. First, the discharge started near the focal point and then developed bidirectionally toward the high‐voltage electrode and the grounded electrode. Midgap leaders were frequently observed. Second, it was observed that the lifetime of the laser‐ionized plasma channel was about 1 μs. Third, the discharge processes were classified into six stages. The mechanism of the streamer and leader propagation is discussed. © 2000 Scripta Technica, Electr Eng Jpn, 134(2): 11–18, 2001 相似文献