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91.
92.
Real-Time Omnidirectional Image Sensors 总被引:1,自引:1,他引:0
Conventional T.V. cameras are limited in their field of view. A real-time omnidirectional camera which can acquire an omnidirectional (360 degrees) field of view at video rate and which could be applied in a variety of fields, such as autonomous navigation, telepresence, virtual reality and remote monitoring, is presented. We have developed three different types of omnidirectional image sensors, and two different types of multiple-image sensing systems which consist of an omnidirectional image sensor and binocular vision. In this paper, we describe the outlines and fundamental optics of our developed sensors and show examples of applications for robot navigation. 相似文献
93.
Tomoyuki Kitano Takayuki Wani Toshiyuki Ohnishi Jiang Li-Fen Yasushi Kuroda Atsutaka Kunai Kazuo Sasaki 《Catalysis Letters》1991,11(1):11-18
Catalytic oxidation of benzene in the gas phase has been studied as a function of the catalyst composition, reaction temperature and the feed conditions of reactant gases, hydrogen, oxygen, benzene as well as diluting inert gas. The catalyst tested is composed of Pd and Cu(I) ions, both of which are supported on silica gel. If one of the two metal species is lacked from the catalyst, no catalytic activity appears. The product is almost exclusively phenol and some accompanying benzoquinone, in particular at lower temperatures, as minor byproduct.On leave from Hua-Dong Institute of Technology, Nanjing, People's Republic of China. 相似文献
94.
Koichi Nagamoto Kunihisa Kato Satoshi Naganawa Takeshi Kondo Yasushi Sato Hisao Makino Naoki Yamamoto Tetsuya Yamamoto 《Thin solid films》2011,520(5):1411
We investigated the characteristics of highly transparent conductive Ga-doped ZnO (GZO) polycrystalline films of 100 nm thickness deposited on glass and polymer substrates. GZO films were deposited by ion plating with dc-arc discharge. We developed multiple-deposition method to obtain various deposition process temperatures lower than 100 °C. Cross-sectional SEM images show that all the GZO films have columnar structure. Analysis of data obtained by XRD measurements shows that all the GZO films with wurtzite structure exhibit highly (002) orientation perpendicular to the substrate. The resistivity of the GZO films deposited on polyester and glass substrates were 5.0 × 10-4 Ω · cm. The mechanical bending properties of the GZO films were investigated by comparing the sheet resistance determined before and after a bending test with various bending diameters. For the bending diameter of more than 30 mm, all the GZO films exhibited excellent bending properties with no change in sheet resistance. For the bending diameter of less than 20 mm, we found the sheet resistance affected by the bending. We demonstrated that our multiple-deposition method to achieve different controllable polyester substrate temperatures is highly suitable for improving the bending properties of GZO films. 相似文献
95.
The effect of reducing agents on the synthesis of Au(0) metallic nanoparticles (Au NPs) prepared in green solvent medium of β-d-glucose-water dispersions has been reported first. The different equivalent amounts of NaBH4 and pH values adjusted by NaOH were tested for the reduction of Au salt (HAuCl4·3H2O (hydrogen tetrachloroaurate (III) trihydrate) to obtain Au NPs. The type and the amount of reducing agent and the pH of the solution affected the size and morphology of the NPs. Addition of 4 equivalents of NaBH4 produced homogeneously dispersed 5.3 nm (σ = 0.7) diameter particles. Excess addition of NaBH4 caused the NPs to settle down as the precipitate forming mesh or wire structure. When salt was reduced by the addition of NaOH (pH = 8.0) the particles were larger (14.2 nm) and less homogeneous (σ = 2.8). At pH = 12.2 the NPs settled at the bottom of the vial when preparation was left overnight. The wire and mesh like structures were obtained at higher pH = 12.2. 相似文献
96.
A two-scale evaluation concept of remediation technologies for a contaminated site was expanded by introducing life cycle costing (LCC) and economic input-output life cycle assessment (EIO-LCA). The expanded evaluation index, the rescue number for soil (RNSOIL) with LCC and EIO-LCA, comprises two scales, such as risk-cost, risk-energy consumption or risk-CO2 emission of a remediation. The effectiveness of RNSOIL with LCC and EIO-LCA was examined in a typical contamination and remediation scenario in which dieldrin contaminated an agricultural field. Remediation was simulated using four technologies: disposal, high temperature thermal desorption, biopile and landfarming. Energy consumption and CO2 emission were determined from a life cycle inventory analysis using monetary-based intensity based on an input-output table. The values of RNSOIL based on risk-cost, risk-energy consumption and risk-CO2 emission were calculated, and then rankings of the candidates were compiled according to RNSOIL values. A comparison between three rankings showed the different ranking orders. The existence of differences in ranking order indicates that the scales would not have reciprocal compatibility for two-scale evaluation and that each scale should be used independently. The RNSOIL with LCA will be helpful in selecting a technology, provided an appropriate scale is determined. 相似文献
97.
Ayami Saga Masahiro Koseki Kotaro Kanno Jiuyang Chang Tomoaki Higo Daisuke Okuzaki Takeshi Okada Hiroyasu Inui Masumi Asaji Katsunao Tanaka Takashi Omatsu Sae Nishihara Yinghong Zhu Kaori Ito Hiroaki Hattori Ikuyo Ichi Yoshihiro Kamada Masafumi Ono Toshiji Saibara Tohru Ohama Shungo Hikoso Makoto Nishida Shizuya Yamashita Yasushi Sakata 《International journal of molecular sciences》2022,23(24)
Patients with psoriasis are at a higher risk of developing nonalcoholic fatty liver disease. We previously identified an oxidized derivative of cholesterol, 7-ketocholesterol (7KC), in diet-induced steatohepatitic mice. Here, we investigated whether 7KC exacerbates psoriasis-like dermatitis by accelerating steatohepatitis in mice. A high-fat/high-cholesterol/high-sucrose/bile salt diet (nonalcoholic steatohepatitis (NASH) diet) with or without 0.0125% 7KC was fed to C57BL/6 mice (7KC or control group) for three weeks to induce steatohepatitis. A 5% imiquimod cream was then applied to the ears and dorsal skin for four days to induce psoriasis-like dermatitis. Hepatic lipid accumulation and inflammatory cell infiltration were exacerbated in the 7KC group compared with the control group after three weeks. Serum tumor necrosis factor-α (TNF-α) levels were also elevated in the 7KC group (108.5 ± 9.8 vs. 83.1 ± 13.1 pg/mL, p < 0.005). Imiquimod cream increased the psoriasis area severity index (PASI) score in mice in the 7KC group (9.14 ± 0.75 vs. 5.17 ± 1.17, p < 0.0001). Additionally, Tnfa, Il23a, Il17a, and Il22 mRNA levels in the dorsal lesion were significantly upregulated. Finally, Th17 cell differentiation and the TNF signaling pathway were enhanced in the dorsal lesions and liver of mice in the 7KC group. These data suggest that steatohepatitis and psoriasis are linked by a potent, diet-related factor. 相似文献
98.
A classical many-body potential for transition metal carbide cluster is developed in the form of the bond-order type potential function. The parameter sets between carbon atoms and several transition metal atoms (Fe, Co and Ni) are constructed by fitting binding energies from Density Functional Theory (DFT) calculations. Using the potential function, clustering process of carbon atoms to a small metal cluster is studied by classical molecular dynamics (MD) simulation. The number of hexagonal rings in the Co cluster increases about twice as fast as in the Fe cluster. This implies that the graphitic lattice interacts more strongly with Co atoms than with Fe atoms. A Co cluster has a crystal structure where metal atoms are regularly allocated and embedded in the hexagonal carbon network in the simulation. In contrast, carbon atoms cover the entire surface in case of the Fe cluster. Additionally, the potential energy surface that a carbon atom feels from a 2D closed-packed facet is examined using a hypothetical FCC(1 1 1) facet of several transition metals. The potential energy minima are distributed on the hexagonal network showing the 2D closed-packed facet can be a template where a graphene is formed. 相似文献
99.
Yasushi Sumi Yutaka Ishiyama Fumiaki Tomita 《Computer Vision and Image Understanding》2007,105(3):218-230
This paper presents a new robot-vision system architecture for real-time moving object localization. The 6-DOF (3 translation and 3 rotation) motion of the objects is detected and tracked accurately in clutter using a model-based approach without information of the objects’ initial positions. An object identification task and an object tracking task are combined under this architecture. The computational time-lag between the two tasks is absorbed by a large amount of frame memory. The tasks are implemented as independent software modules using stereo-vision-based methods which can deal with objects of various shapes with edges, including planar to smooth-curved objects, in cluttered environments. This architecture also leads to failure-recoverable object tracking, because the tracking processes can be automatically recovered, even if the moving objects are lost while tracking. Experimental results obtained with prototype systems demonstrate the effectiveness of the proposed architecture. 相似文献
100.
A novel technique of spectroscopic imaging using a near-infrared (NIR) laser sheet beam was developed for visualization of liquid water in a proton-exchange membrane (PEM) sandwiched between two opaque electrodes set in a polymer electrolyte fuel cell (PEFC). In-plane two-dimensional distribution of water in the thin membrane was clearly visualized during the fuel cell operation. Under the condition of fuel feeding into the PEFC without humidification, water was generated by the fuel cell reaction in the whole electrode area. In contrast, under the condition of fuel feeding with humidification, the PEM got wet in the vicinity of a gas flow field locally. 相似文献