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排序方式: 共有457条查询结果,搜索用时 15 毫秒
31.
Takashi Nagano 《控制论与系统》2013,44(4):77-90
Abstract Most learning machines are of a single type. Input patterns are transformed into some other patterns by a processor then classified by a discriminant function. Such machines are considered to offer poor information processing capability. This paper proposes a new and unusual model of learning. In conventional machines only the classification of input patterns is learned; however, the new model can memorize the input patterns themselves in the learning, that is, an input pattern appears as an output if it has been seen sufficiently often. Basic to the formulation of the new model are the multiplexing of local processing and the use of connections which operate on a manner similar to presynaptic inhibition. 相似文献
32.
Tosaka T. Nagano I. Yagitani S. Yoshimura Y. 《Electromagnetic Compatibility, IEEE Transactions on》2005,47(2):352-360
In order to determine the relative permeability and conductivity of thin materials that could not be found using traditional methods, we constructed a shield box and developed a measuring system to estimate the unknown electric parameters of exotic shielding materials such as thin cloths. Thin electromagnetic shielding sheets of both nonmagnetic materials and ferromagnetic materials were used. The shielding effectiveness of the materials was measured as a function of frequency, and the results were compared with the calculated solutions for a multilayered model that was evaluated using the Sommerfeld integral that expresses near-field spherical waves by a composition of cylindrical waves. In these calculations, the relative permeability and conductivity were varied to determine the solution closest to the measured results. The least squares method was used to determine the best fitted values. Initially the nominal values of relative permeability were assumed, and the conductivity was found using the fitting technique. Then this determined value of the conductivity was assumed, and the relative permeability was found using the fitting technique. For the nonmagnetic materials, the estimated relative permeability was the same as the nominal values. For the ferromagnetic materials, the estimated relative permeability varied 0%-30% from the nominal values. For both types of materials, the estimated conductivities were 0%-9.8% different from nominal values. This research details a new method for evaluating the attenuation of interfering electromagnetic waves for thin materials. 相似文献
33.
This paper attempts to draw quantitative prospects of spent nuclear fuel (SNF) management in Japan, with emphasis on uncertainty of storage needs for SNF up to the year 2050. In a medium term up to the years 2020–2030, the storage need for SNF can be projected with relatively high accuracy as it steadily increases up to the level of 5000 tonnes of uranium (tU), which requires timely deployment of storage facilities accordingly. In a longer term up to 2050, a number of aspects may give influences on the SNF management strategy, which are analyzed in different sets of scenario assumptions. The results of quantitative simulation runs showed that the storage need for SNF will increase up to the level of 10,000 tonnes of heavy metals (tHM) in the Base Case, while it would further grow to 20,000–25,000 tHM in the Risk Management Cases. Careful attentions should be given to the point that not just quantity but characteristics of SNF to be stored will differ significantly among the simulation cases, such as from lower to higher burnup, uranium and MOX (mixed oxide) fuels. The results imply Japan's SNF management may require elaborate strategies, which consists of effective and timely measures into the future. 相似文献
34.
Dr. Masanobu Nagano Takumi Oguro Ryo Sawada Dr. Toru Yoshitomi Prof. Keitaro Yoshimoto 《Chembiochem : a European journal of chemical biology》2021,22(23):3341-3347
Dysregulation of tumor necrosis factor-α (TNFα), a pro-inflammatory cytokine, causes several diseases, making it an important therapeutic target. Here, we identified a novel DNA aptamer against human TNFα using in vitro selection, which included a high exclusion pressure process against non-binding and weak binders through microbead-assisted capillary electrophoresis (MACE) in only three rounds. Among the 15 most enriched aptamers, Apt14 exhibited the highest inhibitory activity for the interaction between TNFα and its cognate receptor in mouse L929 cells. For further improving the bioactivity of the aptamer, dimerization programed by hybridization was evaluated, resulting in the Apt14 dimer exhibited a twofold higher binding affinity and stronger inhibition compared to the monomer counterpart. Rapid identification of bioactive aptamers using MACE in combination with facile dimerization by hybridization accelerates the discovery of novel bioactive aptamers, paving the way toward replacing current monoclonal antibody therapy with the less expensive and non-immunogenic aptamer therapy. 相似文献
35.
Oda E. Nagano K. Tanaka T. Mutoh N. Orihara K. 《Solid-State Circuits, IEEE Journal of》1989,24(3):711-717
A 1920(H)×1035(V)-pixel high-definition CCD (charge-coupled-device) image sensor compatible with an 1125-scanning-lines and 16:9 aspect-ratio television system is described. The device basically uses an interline scheme with a vertical overflow drain. To maintain 74.25-MHz ultrahigh-data-rate operation, the device adopts a dual-channel configuration for the horizontal CCD (H-CCD) register. To accomplish both vertical signal charge transfer in the vertical CCD (V-CCD) register and signal charge distribution from the V-CCD registers into the dual-channel horizontal CCD registers simultaneously within a 3.77-μs short horizontal blanking period, a one-horizontal-period signal storage memory electrode and optical black memory are introduced. Bipolar buffer transistor chips are hybridized in the same package as the device, so as to reduce parasitic capacitance at CCD output terminals and maintain a wide-bandwidth operation. The device operates successfully and 1000-TV-line limiting resolution was obtained for both vertical and horizontal directions. Total random noise was evaluated to be 41 electrons. Dynamic range reached 66 dB. Signal-to-noise ratio for a black/white (B/W) camera was 51.5 dB under F4.0 and 2000-lux illumination conditions 相似文献
36.
Itoh A. Takahashi W. Nagano H. Kurisaka M. Iwasaki S. 《Selected Areas in Communications, IEEE Journal on》1991,9(8):1280-1288
The practical implementation of a trial large-scale asynchronous transfer mode (ATM) switching system and its packaging technologies are described. The architecture of the ATM switching system is discussed with an emphasis on system scalability. A building block architecture in which switching capacity can be expanded in a modular fashion is introduced. The design of the ATM switching system, including the ATM switch element, is described. The implementation of the VLSIs for the ATM switch which realize a highly modular system is explained. Bit-slice techniques are effectively used to realize a high-speed switch element as a CMOS VLSI chipset. An edge-to-edge orthogonal packaging technique is also presented 相似文献
37.
Degradation mechanism of H2 permselectivity under atmosphere of steam/N2 = 3 at 773 K was investigated among amorphous silica membranes on γ-Al2O3-coated α-Al2O3 or Ni-doped γ-Al2O3-coated α-Al2O3 synthesized by counter diffusion chemical vapor deposition. Helium and H2 permeance drastically decreased during the first few hours of hydrothermal exposure. On the other hand, N2 permeance fluctuated during hydrothermal treatment in silica membrane on γ-Al2O3-coated α-Al2O3. The degree of N2 permeance change depended on the hydrothermal stability of the intermediate layer. Hydrogen permselectivity was affected by both the densification of amorphous silica and the sintering of the intermediate layer during hydrothermal exposure. 相似文献
38.
Transport current and n-value of DyBCO-coated conductor pulled in tension were measured experimentally and their relation to crack-induced current shunting was analyzed with the partial crack-current shunting model. The following features were revealed. The shunting current increases with increasing transport current and with increasing crack size. At low voltage where shunting current is low, the transport current of cracked sample normalized with respect to the transport current in non-cracked state is described with the modified ratio of non-cracked area to overall cross-sectional area of superconducting layer. At high voltage where the shunting current is high, the normalized transport current becomes higher than the modified ratio of non-cracked area. The increase in shunting current with transport current (and voltage) leads to a decrease in n-value at high current (voltage). This phenomenon is enhanced by crack extension. 相似文献
39.
Y Sandowski M Nagano C Bignon J Djiane PA Kelly A Gertler 《Canadian Metallurgical Quarterly》1995,115(1):1-11
Zinc is an essential trace element necessary to life. This metal may exert some of its physiological effects by acting directly on cellular membranes, either by altering permeability or by modulating the activity of membrane-bound enzymes. On the other hand, calcium is an essential element in a wide variety of cellular activities. The aim of the present work was to study a possible interaction between zinc and calcium on intestinal transport of D-galactose in jejunum of rabbit in vitro. In media with Ca2+, when ZnCl2 was present at 0.5 or 1 mM, zinc was found to reduce the D-galactose absorption significantly. In Ca(2+)-free media, where CaCl2 was omitted and replaced isotonically with choline chloride, the sugar transport was not modified by zinc. Verapamil at 10(-6) M (blocking mainly Ca2+ transport) did not modify the inhibitory effect of zinc on D-galactose transport. When 10(-6) M of A 23187 (Ca(2+)-specific ionophore) was added with/without Ca2+ to the media, ZnCl2 produced no change in sugar transport. These results could suggest a possible interaction of calcium and zinc for the same chemical groups of membrane, which could affect the intestinal absorption of sugars. 相似文献
40.
Nagano H. Miyano K. Yamada T. Mizushima I. 《Semiconductor Manufacturing, IEEE Transactions on》2005,18(1):13-18
Robustness of a selective epitaxial growth of silicon is demonstrated. The process window of selectivity was estimated quantitatively using the Taguchi method and signal-to-noise ratio analysis for the first time. Both the number of the silicon nuclei on the mask layer and the growth rate of silicon on a silicon substrate were investigated as the output parameters of the Taguchi method. One of the most effective process parameters for the suppression of silicon nucleation on the mask layer without retarding the growth rate of silicon is revealed to be the flow rate of SiH/sub 2/Cl/sub 2/. By calculating the number of the silicon nuclei, which could not be detected by an available measurement method, the process window of the selectivity could be determined with which a wafer with selective epitaxial silicon layer having LSI-quality could be fabricated. A high-quality silicon-on-insulator (SOI) wafer that has both an SOI region and bulk-silicon region can be obtained, and a high-quality embedded device could be realized on the SOI wafer. 相似文献