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101.
A novel and robust statistic as a similarity measure for robust image registration is proposed. The statistic is named as increment sign correlation because it is based on the average evaluation of incremental tendency of brightness in adjacent pixels. It is formalized to be a binary distribution or a Gaussian distribution for a large image size through statistical analysis and modeling. By utilizing the proposed statistical model, for example, we can theoretically determine a reasonable value of threshold for verification of matching. This sign correlation can also be proved to expectedly have the constant value 0.5 for any uncorrelated images to a template image, and then the property of the constancy can be utilized to analyze the high robustness for occlusion. The good performance for the case of saturation or highlight can also be proved through theoretical analysis and fundamental experiments. A basic algorithm for image scanning, search and registration over a large scene is represented with a technique for a fast version by the branch-and-bound approach. Many experimental evidences with real images are provided and discussed.  相似文献   
102.
A case undergoing conduit procedure for tetralogy of Fallot with pulmonary atresia was complicated postoperatively by bacteremia due to non-fermentative Gram-negative rods and by disseminated intravascular coagulation. He was able to be cured without any sequela. The patient was a 16-year-old male, who had undergone Blalock-Taussig anastomosis in his infancy. The present operation was carried out as follows: ventricular septal defect was closed with a Teflon-patch and discontinuity between the right ventricle and the pulmonary artery was corrected using a Hancock's valved conduit. Two weeks after the operation, pleural effusion in the right chest cavity was shown by a chest X-ray film. On the 32nd postoperative day, high fever with chills occurred, and subsequently developed pulmonary edema, shock and hemorrhagic tendencies with petechia. Pseudomonas aeruginosa, Flavobacterium and Alcaligenes faecalis were detected by the culture of pleural effusion. The platelet count decreased to about 10,000/microliters. Carbenicillin, tobramycin and minocycline were administered for the infection, and heparin and aprotinin were used for disseminated intravascular coagulation. By these treatments for about 6 months, the patient became well and was discharged without any sequela.  相似文献   
103.
104.
A total of 137 Enterococcus strains isolated from chicken meat were subjected to antimicrobial susceptibility tests. Strains with the vanCl gene were isolated from seven of nine samples of chicken meat processed in Japan and from all chickens from China and Brazil between July 2001 and April 2002. The pulsed-field gel electrophoresis (PFGE) patterns of the isolates were distinguishable from each other, suggesting that VanCl-type vancomycin-resistant Enterococcus is preferentially colonized in broiler chickens in these countries. The incidence of high-level gentamicin resistant (HLGR) enterococci that harbored the aac(6')-le-aph(2")-la or aph(2')-Id gene varied among the countries from which the chickens originated (Japan, 2 of 65; China, 11 of 43; Brazil, 6 of 29). Moreover, the PFGE patterns of the HLGR strains were distinguishable from each other, except for two strains obtained from chickens from Brazil. The results suggest that HLGR Enterococcus is highly prevalent in broiler chickens.  相似文献   
105.
Chemical structural analysis of tape-stripped surfaces at dark spots growing in organic electroluminescent (EL) devices during exposure to the atmosphere was done by time-of-flight secondary ion mass spectrometry (OF-SIMS). The EL devices consist of indium-tin-oxide, triphenylamine-tetramer, tris(8-hydroxyquinoline)aluminum (Alq3), and a Mg-Ag cathode deposited in order under vacuum on a glass substrate. It was found that the interface between the Alq3 layer and the Mg-Ag cathode was exposed as a result of tape-stripping, where a large number of dark spots were observed on both sides. Secondary ion images of O-, Mg+, and Alq2+ were observed from the dark spots on the cathode side. On the other hand, Mg+ and O- images with a nucleus in the center were observed from the Alq3 side. It is concluded from the results that the constituent element Mg of the cathode was oxidized at the interface adjacent to the Alq3 layer during exposure to the atmosphere, forming a dark spot with a nucleus in the center. Finally, it was confirmed that the TOF-SIMS analysis of the tape-stripped surface is useful for the analysis of the mechanism of dark spot formation.  相似文献   
106.
Wireless communications are expected to be the dominant mode of access technology in the next century. Besides voice, a new range of services such as multimedia, high-speed data, etc. are being offered for delivery over wireless networks. Mobility will be seamless, realizing the concept of persons being in contact anywhere, at any time. Two developments are likely to have a substantial impact on the mobile communications systems deployed in the twenty-first century: the adoption of International Mobile Telecommunications-2000 and wireless asynchronous transfer mode (ATM). They are two different but cooperative approaches to providing high-speed wireless access. The limitations of the radio-frequency spectrum and radio channel propagation impose special constraints on the technologies of systems to be deployed. To make future mobile systems globally acceptable, standardization efforts are underway in the International Telecommunications Union and the ATM Forum. This paper reviews the international standardization efforts, the challenges to the technologies imposed by the radio spectrum limitations, radio channel propagation-induced distortions, and possible solutions. Evolution, migration, and architecture issues also are discussed  相似文献   
107.
Enterococcus faecium and Enterococcus gallinarum strains were isolated from a commercial probiotic product and the effects of these strains on the growth of Salmonella enterica serovar Enteritidis strain IFO3313 were investigated. Viable cell counts of Salmonella Enteritidis in mixed cultures with the probiotic product isolate of E. faecium were significantly (P < 0.05) lower than those in pure cultures after 6, 8, and 24 h when the cultures were incubated in heart infusion broth at 37 and 41 degrees C. Significant differences in viable cell counts of Salmonella Enteritidis in mixed cultures with the probiotic product isolate of E. gallinarum and those in pure cultures were also observed after 8 and 24 h at 37 and 41degrees C. Similar observations were shown in mixed cultures of Salmonella Enteritidis with the reference strains of E. faecium GIFU8355 and E. gallinarum ATCC 49573. Significant differences in viable cell counts of these enterococcal strains were not shown among pure and mixed cultures with Salmonella Enteritidis. The pH values in pure and mixed cultures were 7.0 or 7.5 throughout the experiments. E. faecium strains were found to harbor the genes encoding enterocins A and B and showed inhibitory zones with a diameter of 4 to 6 mm against growth of Salmonella Enteritidis in the enterocin production assays. However, the E. gallinarum strains possessed neither of the enterocin genes tested and exhibited no inhibition zone in the enterocin production assays. These results indicated that enterococcal strains exhibit inhibitory effects on the growth of Salmonella Enteritidis and these effects were due to both enterocin and nonenterocin factors.  相似文献   
108.
109.
The authors point out that a TEOS/O3-oxide layer used as an interlevel dielectric enhances hot-carrier degradation of MOSFETs due to the water-related components (water and/or silanols) contained in the layer. This results mainly from enhanced hot-electron trapping in the gate oxide and also from interface-trap generation. By applying an ECR-SiO2 layer under the TEOS/O3-oxide layer, tolerance against hot-carrier damage is improved to the level of MOSFETs without the TEOS/O3 oxide. From ESR measurement results, it is found that the spin density of the ECR-SiO2 film under the TEOS/O3 oxide is two orders lower than that of the ECR-SiO 2 film only. It is suggested that the dangling bonds in the ECR-SiO2 film effectively trap water diffusing from the water-containing overlayer  相似文献   
110.
A Si single electron transistor (SET) was fabricated by converting a one-dimensional Si wire on a SIMOX substrate into a small Si island with a tunnelling barrier at each end by means of pattern-dependent oxidation. With this structure, the total capacitance was reduced to ~2aF, which enabled conductance oscillation of the SET at room temperature  相似文献   
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