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41.
Kobayashi S 《Applied optics》2002,41(14):2679-2685
A point-spread function (PSF) is commonly used as a model of an optical disk readout channel. However, the model given by the PSF does not contain the quadratic distortion generated by the photo-detection process. We introduce a model for calculating an approximation of the quadratic component of a signal. We show that this model can be further simplified when a read-only-memory (ROM) disk is assumed. We introduce an edge-spread function by which a simple nonlinear model of an optical ROM disk readout channel is created. 相似文献
42.
43.
Kino K Murakami-Nitta T Oishi M Ishiguro S Kirimura K 《Journal of Bioscience and Bioengineering》2004,97(1):82-84
With the objective of developing an odorless biodegradation process for dimethyl sulfoxide (DMSO), Hyphomicrobium sp. WU-OM3 was isolated. During the cultivation of strain WU-OM3 cells with 20 mM dimethyl sulfone (DMSO2) as the sole carbon source, DMSO2 was completely consumed within 48 h and sulfate ion accumulated in the culture broth. Methanesulfonate was also detected as an intermediate of DMSO2 degradation. By combining the DMSO-oxidizing microorganism and strain WU-OM3 cells, 0.64 mM (50 mg/l) DMSO was degraded to sulfate ion with 80% molar conversion ratio. 相似文献
44.
The purpose of this research was to investigate the ice growth of a single crystal in three dimensions. Three-dimensional pattern of ice crystal growth in supercooled water was observed using Mach–Zehnder spectro-interferometer. Temperature was varied from −0.3 to −1.6 °C. It was found that the ice crystal began to grow as a single crystal at the tip of the capillary tube and propagated freely in supercooled water. Time variation of the shape of dendrite on a–c plane was obtained. It was found that half parabola fits the shape very closely, and the coefficient of squared term, a, of a quadratic function was calculated. The coefficient, a varied in time but at quasi steady state it was found to be depending mostly upon the degree of supercooling. Furthermore, the growth velocity in c-axis at the flat surface was calculated from the thickness measured. It was found that the velocity in c-axis is independent of the degree of supercooling but depends upon time, in other words, the thickness in c-axis. 相似文献
45.
46.
Transparent hexagonal BN films were deposited onto copper substrates from the reactant gas BCl3-NH3-H2 at temperatures in the range 250–700°C. The lowest deposition temperature of the films was about 250°C. The films deposited at temperatures below 450°C were unstable in moist atmosphere and devitrified; a 20%–30% decrease in weight was observed when these films were heated above 600°C in an argon atmosphere. In contrast, the films deposited at temperatures above 600°C were very stable, decreased in weight by 1%–2% on heating and were stable in air at temperatures below 750°C. 相似文献
47.
In this paper, the authors propose a method that incorporates mechanisms for handling ambiguity in speech and the ability of humans to create associations, and for formulating conversations based on rule base knowledge and common knowledge. Go beyond the level that can be achieved, using only conventional natural language processing and vast repositories of sample patterns. In this paper, the authors propose a method for computer conversation sentences generated using newspaper headlines as an example of how the common knowledge and associative ability are applied. 相似文献
48.
On the heat removal characteristics and the analytical model of a thermal energy storage capsule using gelled Glauber's salt as the PCM 总被引:1,自引:0,他引:1
Akio Saito Seiji Okawa Tadafumi Shintani Ryuichiro Iwamoto 《International Journal of Heat and Mass Transfer》2001,44(24):4693-4701
An analytical and experimental investigation was performed on a heat removal process of the thermal energy storage (TES) capsule, using gelled Glauber's salt. Transient heat flux at the capsule wall was measured for various cooling conditions. In cases where the initial temperature was lower than the saturation temperature of the phase change material (PCM), numerical analyses were performed, approximating the process by a relaxation phenomenon where crystals grew around crystal nuclei. The results of the numerical solution agreed very well with the experimental results. 相似文献
49.
We discuss the general theoretical arguments advanced earlier for the T=0 global phase diagram of antiferromagnetic Kondo lattice systems, distinguishing between the established and the conjectured. In addition to the well-known phase of a paramagnetic metal with a “large” Fermi surface (PL), there is also an antiferromagnetic phase with a “small” Fermi surface (AFS). We provide the details of the derivation of a quantum non-linear sigma-model (QNLσM) representation of the Kondo lattice Hamiltonian, which leads to an effective field theory containing both low-energy fermions in the vicinity of a Fermi surface and low-energy bosons near zero momentum. An asymptotically exact analysis of this effective field theory is made possible through the development of a renormalization group procedure for mixed fermion-boson systems. Considerations on how to connect the AFS and PL phases lead to a global phase diagram, which not only puts into perspective the theory of local quantum criticality for antiferromagnetic heavy fermion metals, but also provides the basis to understand the surprising recent experiments in chemically-doped as well as pressurized YbRh2Si2. We point out that the AFS phase still occurs for the case of an equal number of spin-1/2 local moments and conduction electrons. This observation raises the prospect for a global phase diagram of heavy fermion systems in the Kondo-insulator regime. Finally, we discuss the connection between the Kondo breakdown physics discussed here for the Kondo lattice systems and the non-Fermi liquid behavior recently studied from a holographic perspective. 相似文献
50.
Surface properties of carbon micro-coils oxidized by a low concentration of oxygen gas 总被引:1,自引:0,他引:1
Vapor-grown carbon micro-coils were oxidized under a low O2 flow-rate for introducing oxygen-containing functional groups on the surface. The surface characteristics were then examined. The O1s/C1s intensity ratios of the XPS spectra measured on the surface increased on using the oxidation treatment. The maximum O1s/C1s ratio of 11.4 at.% was obtained under the following conditions: (a) the flow-rate of the mixed gas of O2+Ar (O2/Ar=1/10) was 82.5 sccm; (b) the oxidation temperature was 600°C; and (c) the treatment time was 30 min. The maximum O1s/C1s ratio is about 3.5 times that of the source carbon coils. The specific surface area significantly increased due to the oxidation treatment and attained a maximum value of 1050 m2 g−1, which is about 10 times that of the source carbon coils. As the specific surface area increased, the surface morphology of the carbon coils became more complicated on a nanometer scale. 相似文献