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91.
Mattausch H.J. Gyohten T. Soda Y. Koide T. 《Solid-State Circuits, IEEE Journal of》2002,37(2):218-227
An associative-memory architecture for a fully parallel minimum Hamming distance search is proposed, which uses digital circuitry for bit comparison and fast analog circuitry for word comparison as well as winner-take-all (WTA) functionality. Following this original approach allows compact and high-performance integration in conventional CMOS technology. First, static encoding of word-comparison results as a current-sink capability reduces word-comparison circuitry to the theoretical minimum, namely, one transistor per bit and one signal line per word. Second, a new WTA principle, which we call self-adapting winner line-up amplification (WLA), regulates the winner row output automatically into the narrow maximum-gain region of a distance amplifier. Third, winner search circuit complexity scales linear with reference-word number and not quadratic as inevitable for digital approaches. Due to static distance encoding and WLA regulation, transient noise and fabrication process variations are largely tolerated. Only relative chip-internal transistor-parameter variations, creating effective mismatch of matched transistors, limit winner search result correctness. Practical feasibility is verified 相似文献
92.
93.
K. Hashimoto Y. Koide O. Tadanaga T. Oku N. Teraguchi Y. Tomomuea A. Suzuki Masanori Murakami 《Journal of Electronic Materials》1996,25(12):1823-1831
In order to explore a possibility of forming an intermediate semiconductor layer with low Schottky barrier by the conventional
deposition and annealing technique, the electrical properties of Cd and Te-based contacts on the nitrogendoped ZnSe substrates
have been investigated. Cd in the Cd/W contact reacted with the ZnSe substrate after annealing at temperatures above 250°C
and formed epitaxial Ccx}Zn1−xSe layers, leading to reduction of the “turn-on” voltage (VT) from about 11 to 6 V (here, a slash “/” between Cd and W means the deposition sequence). The reduction of the Vn} value by annealing at elevated temperatures was also observed for the Bi-Cd/W and In-Cd/W contacts. The average Cd composition
(x) in the Cdn}Zn1−xSe layers was measured to be larger than 0.9, which agreed with the values estimated from the calculated Cd-Zn-Se phase diagrams.
The ohmic behavior was strongly influenced by the thickness of the CdxZn1−xSe layer, the density of misfit dislocations formed at the interface between the Cdx Zn1−x Se and the ZnSe, and/or the total area of the Cd Zn. Se layers covering the ZnSe surface. The present result suggests that
formation of the large-areal CcxZn1−xSe layers with thin thickness is crucial to achieve further reduction of the VT value by the conventional deposition and annealing technique. Also, the VT reduction was not obtained for the Te/W contact even after annealing at temperatures close to 300°C, which was explained
to be due to absence of ternary ZnSe1−xTen intermediate layers. 相似文献
94.
T. Kagawa Yasuo Koide T. Oku H. Mori N. Teraguchi Y. Tomomura A. Suzuki Masanori Murakami 《Journal of Electronic Materials》1998,27(8):998-1002
The effects of formation of intermediate semiconductor layers at p-ZnSe/metals interfaces on carrier transport mechanisms
were studied by comparing contacts prepared by the deposition and annealing (DA) technique or the molecular beam epitaxy (MBE)
technique. Current density vs voltage (J-V) curves of the MBE contact with a p-ZnSe/p-ZnTe superlattice intermediate layer
showed ohmic behavior. However, J-V curves of the DA contact with a ZnTe intermediate layer showed rectifying behavior. The
difference of the electrical properties between these two contacts was due to existence of a highly resistive intermediate
layer with highly dense defects in the DA contact and a low resistance p-type conductive intermediate layer with relatively
small densities of crystalline defects in the MBE contacts. From the present results, it was concluded that formation of the
highly resistive semiconductor layer with dense crystalline defects prevented the DA contact to transit from non-ohmic J-V
behavior to ohmic. 相似文献
95.
Ju DY Bian P Kumazawa T Nakano M Matsuura H Umetani K Komdo T Uozumi Y Makino K Noda N Koide K Akutsu M Masuyama K 《Journal of nanoscience and nanotechnology》2011,11(10):8738-8743
In this study, the composite magnetic nanoparticles of coated SiO nano film with about 8 nm size and high saturation magnetization value, were synthesized by liquid phase precipitation method. The magnetic nanoparticles can be dispersed in various liquid media, widely known as magnetic fluids or ferrofluids with both magnetic and liquid properties. The materials been collected great interests and more and more attentions to focus into Drug Delivery System (DDS) as a new technology in this paper. We use the composite nanoparticles to disperse H2O and inject the solutions into rat's in-vivo organs. And, in the experiments by using a strong photon beam of SPring-8 Synchrotron Radiation facility, the distribution stat and the effects of magnetic field as well as drug delivery behaviour of nanoparticles in the rat' kidney are verified by the in-vivo observations. 相似文献
96.
Abstract The long-term safety assessment of CO_2 aquifer storage requires a deep understanding of permeability evolutionduring inelastic deformations in sedimentary rocks. The permeability change has been measured in the entire process fromelastic, plastic, post-failure to axial stress unloading for Shirahama sandstone subjected to triaxial compressions undervarious confining pressures. The measurements revealed that the confining pressure plays an important role in controllinginelastic deformation behavior and the tendency of the permeability evolution. In the brittle faulting regime under a lowconfining pressure, significant increase in permeability accompanied by dilatancy can be observed. In brittle-ductile transition 相似文献
97.
A parallel redundancy has been researched in a great amount of literature on reliability theory. In the real circumstances, however, it is seldom observed except some systems that require much higher reliability. This is because most of the literature only look at the manufacturer’s point of view. The present study carries out an economic analysis of an n-unit parallel redundant system against a single unit system based on a Stackelberg game formulation considering both the consumer’s viewpoint and the manufacturer’s one. It clarifies quantitatively in what situation the manufacturer can increase his profit by dealing in the parallel redundant system. 相似文献
98.
Hanaoka R. Nakamichi H. Takata S. Koide H. Hatta Y. 《Dielectrics and Electrical Insulation, IEEE Transactions on》2006,13(3):526-531
The basic properties of electrohydrodynamic (EHD) pumping and dielectric strength were examined for two insulating oils, rapeseed ester oil and silicone oil, which were denatured by a bonding of hydrofluorocarbon (HFC)134a gas components decomposed using a barrier discharge reactor. In this work, the mechanism of a pure conduction pumping contributed to the evaluation of the electrical pumping in sample oils. Dielectric strength of oils was evaluated from the impulse creeping discharge characteristics and the 60 Hz breakdown voltage test. Experimental results revealed that the creation of radicals such as C-F and C-H in denatured oils led to a slight deterioration of the insulation ability compared to standard oils, but the pumping ability was reinforced significantly. Such additional EHD function may be utilized as a new cooling method in oil-filled power apparatuses in view of the dielectric strength. 相似文献
99.
Flexible Ultraviolet Photodetectors with Broad Photoresponse Based on Branched ZnS‐ZnO Heterostructure Nanofilms 下载免费PDF全文
100.
BACKGROUND: To clarify an effect of cimetidine on bile acid metabolism, we evaluated whether an increased deconjugation of bile acids would occur in healthy humans who have received cimetidine. We examined: 1) whether healthy volunteers taking cimetidine would have positive bile acid breath tests because of bacterial overgrowth in the jejunum; 2) whether the isolated bacteria would exhibit deconjugation ability; and 3) whether a change in gastric pH was related to the bacterial overgrowth. METHODS: We evaluated 73 healthy Japanese volunteers; 53 of them received cimetidine and 20 did not. Deconjugation of bile acids was detected as 14CO2 specific activity of expired air measured by a bile acid breath test giving 5 muCi of oral glycine-1-(14)C labeled glycocholate. Aspiration of jejunal fluids was performed by a double lumen tube with a rubber cover on the tip, and deconjugation ability of bacteria was evaluated using thin layer chromotography. RESULTS: Samples of expired breath from the 53 healthy volunteers showed a significant increase in 14CO2 specific activity after the administration of cimetidine rather than before the administration of cimetidine. Bacterial over-growth was found in the jejunal fluid after the administration of cimetidine. The administration of tetracycline to 27 subjects significantly reduced the 14CO2 specific activity. The following species were identified in the jejunal fluid samples obtained from the subjects: enterococcus, Lactobacillus bifidus, Bacteroides vulgatus, B uniformis, Eubacterium lentum, E parvum, and Escherichia coli. Except for E coli, all of the bacterial species identified deconjugated bile acids. We observed a significant relationship between 14CO2's specific activity and gastric pH before and after administration of cimetidine, respectively. CONCLUSIONS: Healthy volunteers who received cimetidine showed an increased deconjugation of bile acid caused by overgrowth of bacteria in the jejunum, which can deconjugate bile acids. The bacterial overgrowth is probably associated with a shift to neutral pH in the gastric juice caused by cimetidine. 相似文献