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排序方式: 共有774条查询结果,搜索用时 31 毫秒
61.
62.
Computer vision for interactive computer graphics 总被引:3,自引:0,他引:3
Freeman W.T. Anderson D.B. Beardsley P. Dodge C.N. Roth M. Weissman C.D. Yerazunis W.S. Kage H. Kyuma I. Miyake Y. Tanaka K. 《Computer Graphics and Applications, IEEE》1998,18(3):42-53
Vision can be a powerful interface device for computers because of its potential for sensing body position, head orientation, direction of gaze, pointing commands, and gestures. Such unencumbered interaction can make computers easier to use. We describe vision algorithms for interactive graphics and present vision-controlled graphics applications using these algorithms. Some applications employ an artificial retina chip for image detection or preprocessing 相似文献
63.
Y. Miyake H. Hirayama S. Arai Y. Miyamoto Y. Suematsu 《Photonics Technology Letters, IEEE》1991,3(3):191-192
GaInAs-GaInAsP-InP SCH (separate-confinement heterostructure) multiquantum-film lasers with approximately 100-nm-wide wirelike active regions were fabricated by two-step low-pressure organometallic vapor-phase epitaxy (LP-OMVPE) growth and wet chemical etching and operated at room temperature. An increase in the threshold current density in such lasers was drastically reduced by using a preheating process in hydrogen atmosphere and a thin InP cover layer growth prior to the regrowth of a GaInAsP optical confinement layer. The fabrication processes presented can be very effective for realization of room-temperature operation of long-wavelength quantum-wire and quantum-box lasers based on GaInAs-InP materials.<> 相似文献
64.
Gennadiy A. Medvedkin Takao Nishi Yuji Katsumata Hideto Miyake Katsuaki Sato 《Solar Energy Materials & Solar Cells》2003,75(1-2):135-143
Point defects in CuGaSe2 single crystals as vacancies VSe, VCu and defect pair (2VCu−+GaCu2+) have been studied by means of electron paramagnetic resonance (EPR) and low-temperature photoluminescence (PL). EPR hyperfine structure has been found at temperatures as low as 1.45–45 K and the temperature dependence of EPR line is discussed. Photo-EPR spectrum reveals optically active behavior of intrinsic point defects in CuGaSe2 crystals. Three bands of PL emission show different origins and two low-energy bands at 1.55 and 1.58 eV have been found to be steady despite H2-, O2- and Se2-annealings. The experimental data added with electric characterization in accordance with the used annealings and together with a defect physics model allow consideration of the point defect ensemble in CuGaSe2 in more detail. 相似文献
65.
K Koike Y Sakamoto H Kiyama K Masuhara A Miyake M Inoue 《Canadian Metallurgical Quarterly》1997,52(2):326-329
Cytokine-induced neutrophil chemoattractant (CINC) is one of the chemokines and has chemotaxity for neutrophils. Recently, we found the presence of stress-sensitive CINC expression in the hypothalamic nuclei such as the paraventricular nucleus. Since CINC was predominantly co-localized with vasopressin in the supraoptic nucleus (SON), we investigated the effect of hyperosmotic challenge on CINC mRNA in the hypothalamus. We found that CINC mRNA expression in the hypothalamus was augmented within 30 min following osmotic stimulation and immediately returned to the basal level. The suckling, which is a stimulation to oxytocin neurons in the SON, has no effect on CINC mRNA expression in the hypothalamus. This is the first evidence that the chemokine in the brain is activated by osmotic stimulation. 相似文献
66.
Repeatable change in electrical resistance of Si surface by mechanical and electrical nanoprocessing
The properties of mechanically and electrically processed silicon surfaces were evaluated by atomic force microscopy (AFM). Silicon specimens were processed using an electrically conductive diamond tip with and without vibration. After the electrical processing, protuberances were generated and the electric current through the silicon surface decreased because of local anodic oxidation. Grooves were formed by mechanical processing without vibration, and the electric current increased. In contrast, mechanical processing with vibration caused the surface to protuberate and the electrical resistance increased similar to that observed for electrical processing. With sequential processing, the local oxide layer formed by electrical processing can be removed by mechanical processing using the same tip without vibration. Although the electrical resistance is decreased by the mechanical processing without vibration, additional electrical processing on the mechanically processed area further increases the electrical resistance of the surface. 相似文献
67.
Hydrogen production by combining two types of photosynthetic bacteria with different characteristics
Toshihiko Kondo Masayasu Arakawa Tatsuki Wakayama Jun Miyake 《International Journal of Hydrogen Energy》2002,27(11-12)
The double-layer photobioreactor using two types of photosynthetic bacteria, Rhodobacter sphaeroides RV and its reduced-pigment mutant, MTP4, was developed for efficient hydrogen production. The two types of bacteria had different characteristics on light energy, hydrogen production rate and conversion efficiency. MTP4 produced hydrogen more efficiently under high light conditions and RV did so under low light conditions. Illuminated light toward the surface of a photobioreactor quasi-exponentially declines as it penetrates into the reactor. When two types of bacteria were placed using the developed reactor according to this light distribution, the hydrogen production rate reached 3.64 l/m2/h at a light intensity of 500 W/m2 in 24 h and the conversion efficiency of light energy to hydrogen was 2.18%. These values were 33% higher than those of only using RV. The low light in the deep part of the reactor was utilized efficiently, resulting in a higher hydrogen production rate. 相似文献
68.
A multi-layered photobioreactor (MLPR), where the light paths were formed by the localization of bacterial cells, was constructed for efficient hydrogen production. The performance was investigated under several conditions in order to clarify the effect of this reactor on hydrogen production. An analysis of the hydrogen production profile showed that the MPLR utilizes both the light that directly illuminates its surface and the light induced and diffused from its light paths for hydrogen production. It was also found that the hydrogen productivity in the MLPR was more than twice that in a plate-type reactor. When a photosynthetic bacterium mutant with reduced pigment, MTP4, was used, the maximum hydrogen production rate reached 2.0 l/m2 h, which was 38% higher than that of a conventional plate-type reactor. The synergistic effect of the improvement in the reactor and the modification of the bacteria was brought about by the combination of the MLPR and MTP4, and resulted in an improvement in the hydrogen production. 相似文献
69.
The novel Fe/Nb co-doped SrCo1 ? 2x(Fe,Nb)xO3 ? δ (x = 0.05, 0.10) perovskite oxides were synthesized by the solid-state method. Structural and chemical stability of the SrCo1 ? 2x(Fe,Nb)xO3 ? δ (x = 0.05, 0.10) oxides were studied by differential scanning calorimetry (DSC), thermogravimetric analysis (TG) and X-ray diffraction (XRD). The results demonstrated that the structural and chemical stability of the Fe/Nb co-doped SrCo1 ? 2x(Fe,Nb)xO3 ? δ (x = 0.05, 0.10) is improved significantly. The oxygen sorption properties of the SrCo1 ? 2x(Fe,Nb)xO3 ? δ (x = 0.05, 0.10) oxides were investigated between 300–900 °C in air, and the high oxygen sorption capacity of 11.5 and 10.3 mL O2 (STP)/g oxide, respectively, are obtained. 相似文献
70.
Tajima T Sakata W Wada T Tsutsui A Nishimoto S Miyake M Takaguchi Y 《Advanced materials (Deerfield Beach, Fla.)》2011,23(48):5750-5754
A coaxial nanohybrid consisting of a single-walled carbon nanotube (SWCNT), fullerodendron, and SiO(2) shows high-efficiency light-driven hydrogen evolution from water. Upon visible light irradiation, SWCNT/fullerodendron/SiO(2) coaxial nanohybrid shows hydrogen evolution activity in the presence of methyl viologen (MV(2+)), benzyldihydronicotinamide (BNAH), and a colloidal polyvinyl alcohol(PVA)-Pt. 相似文献