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51.
An Integrated Circuit for Two-Dimensional Edge-Detection with Local Adaptation Based on Retinal Networks 总被引:1,自引:0,他引:1
Hitoshi Yamada Takashige Miyashita Masahiro Ohtani Kimihiro Nishio Hiroo Yonezu Yuzo Furukawa 《Optical Review》2002,9(1):1-8
We designed an integrated circuit for edge detection of a two-dimensional image based on the vertebrate outer retina, which has wide dynamic range in image processing. The unit circuit is simple, and operates as a current-mode analog metal-oxide-semiconductor (MOS) circuit. In order to extract edges from an image composed of bright and dark domains, the circuit realizes a function called local adaptation in which the sensitivity adapts to local brightness of the image. Simulation results, using the simulation program with integrated circuit emphasis (SPICE), of two-dimensional Gaussian-distributed images in which the intensity ranged over four orders of magnitude, showed the local adaptation. As a result, the intensity of output images was in the range of one order of magnitude. Furthermore, as the simulation result of real images, it was shown that edges in the dark domain, which was five times darker than the bright domain, were successfully detected as the bright domain in which input photocurrents ranged over two orders of magnitude. 相似文献
52.
We proposed in this research a novel two-dimensional network based on the frog visual system, with a motion detection function
and a newly developed simple-shape recognition function, for use in object discrimination by integrated circuits. Specifically,
the network mimics the signal processing of the small-field cell in a frog brain, consisting of the tectum and thalamus, which
generates signals of the motion and simple shape of an object. The proposed network is constructed from simple analog complementary
metal oxide semiconductor (CMOS) circuits; a test chip of the proposed network was fabricated with a 1.2 μm CMOS process.
Measurements on the chip clarified that the proposed network can generate signals of the moving direction, velocity, and simple
shape, as well as perform information processing of the small-field cell. Results with the simulation program with integrated
circuit emphasis (SPICE) showed that the analog circuits used in the network have low power consumption. Applications of the
proposed network are expected to realize advanced vision chips with functions such as object discrimination and target tracking. 相似文献
53.
Hitoshi?Yamada Kimihiro?Nishio Masahiro?Ohtani Hiroo?YonezuEmail author Yuzo?Furukawa 《Optical Review》2004,11(5):320-327
Inspired by a mechanism of biological vision systems, a model and a network of analog metal oxide semiconductor (MOS) circuits are proposed which display an optical flow with local adaptation to the relative velocity of a background image. A function of displaying an optical flow successfully worked as a result of simulations using the simulation program with integrated circuit emphasis (SPICE). A function of varying an optical flow at a certain instant by local adaptation was also demonstrated. The proposed network is suitable for the realization of a large-scale integrated circuit (LSI), which displays an optical flow with local adaptation to the local velocity of a background. 相似文献
54.
Metallic Pr, Nd and Dy reacted with iodoethane at room temperature or 65°C in tetrahydrofuran (THF) but Gd, Ho and Er did not. The reaction of PhLnI complexes (Ln-Eu, Sm, Yb) with N,N-dimethylbenzamide gave benzophenone in good yields whilst the reaction of EtSmI with benzaldehyde afforded reduction and coupling products of benzaldehyde. 相似文献
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Kamigaito M Onishi I Kimura S Kotani Y Sawamoto M 《Chemical communications (Cambridge, England)》2002,(22):2694-2695
A fast and controlled radical polymerisation of acrylates and acrylamides can be achieved with a combination of a highly active metal catalyst, Fe2Cp2(CO)4, and a mild radical scavenger, iodine, in the presence of an iodide initiator. 相似文献
58.
Yoshiyuki Kani Shigeru Ohba Yuzo Nishida 《Acta Crystallographica. Section C, Structural Chemistry》2000,56(5):e194-e194
In the title complex, [Mn2(C16H14N2O2)2(C2H3O2)]ClO4, two [Mn(salen)] moieties [salen is bis(salicylidene)ethylenediamine] are connected through a μ‐acetate bridge in a syn–anti fashion. The Mn?Mn distance is 5.365 (1) Å. 相似文献
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Planar binuclear copper(II) complexes generally showed high catalytic activities for the decomposition of hydrogen peroxide compared with the relevant planar mononuclear copper(II) complexes. This result was explained on the assumption that the two-electron transfer occurs between H2O2 molecules via an intervening binuclear copper(II) complex. 相似文献