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51.
Yuzuru Eguchi 《国际流体数值方法杂志》2002,39(11):1037-1052
In the present paper, the author shows that the predictor/multi‐corrector (PMC) time integration for the advection–diffusion equations induces numerical diffusivity acting only in the streamline direction, even though the equations are spatially discretized by the conventional Galerkin finite element method (GFEM). The transient 2‐D and 3‐D advection problems are solved with the PMC scheme using both the GFEM and the streamline upwind/Petrov Galerkin (SUPG) as the spatial discretization methods for comparison. The solutions of the SUPG‐PMC turned out to be overly diffusive due to the additional PMC streamline diffusion, while the solutions of the GFEM‐PMC were comparatively accurate without significant damping and phase error. A similar tendency was seen also in the quasi‐steady solutions to the incompressible viscous flow problems: 2‐D driven cavity flow and natural convection in a square cavity. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献
52.
Higher order effects such as third-order dispersion, shock effect, and soliton self-frequency shift on all-optical logic gates that use asymmetric nonlinear optical fiber couplers are investigated with the beam propagation method, and it is found that third-order dispersion seriously affects the operations of logic devices. In contrast to the case of nonvanishing third-order dispersion, the radiation is stimulated, and consequently the operations of the logic devices are degraded. In order to diminish the degradation, the bandwidth limited amplification is introduced. The logic functions can be improved by trapping only the soliton components in the finite gain-bandwidth 相似文献
53.
54.
Hitomi Murakami Gunkichi Sato Shuichi Matsumoto Tatsuhiko Hirabayashi Hideo Yamamoto Wallance W. Donald Erik Bachmann 《International Journal of Satellite Communications and Networking》1986,4(3):127-137
This paper describes field test results of multi-channel digital TV transmission using a PSK/FDMA system and the related subjective test results of received TV pictures. The picture quality of the multi-channel 15 or 30 Mb/s transmission for both NTSC and PAL systems through the INTELSAT POR satellite are subjectively evaluated for various bit-error rates. In addition, subjective evaluations were made at various values of earth-station e.i.r.p. to compare the picture quality of digital transmissions with that of current half-transponder FM transmission. 相似文献
55.
Shinto Eguchi 《Annals of the Institute of Statistical Mathematics》1986,38(1):385-398
Summary This paper is concerned with estimation for a subfamily of exponential-type, which is a parametric model with sufficient statistics.
The family is associated with a surface in the domain of a sufficient statistic. A new estimator, termed a projection estimator,
is introduced. The key idea of its derivation is to look for a one-to-one transformation of the sufficient statistic so that
the subfamily can be associated with a flat subset in the transformed domain. The estimator is defined by the orthogonal projection
of the transformed statistic onto the flat surface. Here the orthogonality is introduced by the inverse of the estimated variance
matrix of the statistic on the analogy of Mahalanobis's notion (1936,Proc. Nat. Inst. Sci. Ind.,2, 49–55). Thus the projection estimator has an explicit representation with no iterations. On the other hand, the MLE and
classical estimators have to be sought as numerical solutions by some algorithm with a choice of an initial value and a stopping
rule. It is shown that the projection estimator is first-order efficient. The second-order property is also discussed. Some
examples are presented to show the utility of the estimator. 相似文献
56.
57.
Hiroshi KIYONO Tatsuhiko AZEGAMI 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2015,91(8):423-439
The oral cavity is the beginning of the aero-digestive tract, which is covered by mucosal epithelium continuously under the threat of invasion of pathogens, it is thus protected by the mucosal immune system. In the early phase of our scientific efforts for the demonstration of mucosal immune system, dental science was one of major driving forces due to their foreseeability to use oral immunity for the control of oral diseases. The mucosal immune system is divided functionally into, but interconnected inductive and effector sites. Intestinal Peyer’s patches (PPs) are an inductive site containing antigen-sampling M cells and immunocompetent cells required to initiate antigen-specific immune responses. At effector sites, PP-originated antigen-specific IgA B cells become plasma cells to produce polymeric IgA and form secretory IgA by binding to poly-Ig receptor expressed on epithelial cells for protective immunity. The development of new-generation mucosal vaccines, including the rice-based oral vaccine MucoRice, on the basis of the coordinated mucosal immune system is a promising strategy for the control of mucosal infectious diseases. 相似文献
58.
59.
Ohno O Chiba T Todoroki S Yoshimura H Maru N Maekawa K Imagawa H Yamada K Wakamiya A Suenaga K Uemura D 《Chemical communications (Cambridge, England)》2011,47(46):12453-12455
Novel sesquiterpene alkaloids, halichonines A (1), B (2), and C (3), were identified from the marine sponge Halichondria okadai Kadota. By spectroscopic analyses and synthesis, their structures were revealed to include a 6,6-bicyclic ring system and two prenylated amine moieties. In addition, 2 induced apoptosis in HL60 human leukemia cells. 相似文献
60.
Kidera M Seto Y Takahashi K Enomoto S Kishi S Makita M Nagamatsu T Tanaka T Toda M 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,78(3):1215-1219
We developed a detection technology for vapor forms of chemical warfare agents (CWAs) with an element analysis system using an electron cyclotron resonance ion source. After the vapor sample was introduced directly into the ion source, the molecular material was decomposed into elements using electron cyclotron resonance plasma and ionized. The following CWAs and stimulants were examined: diisopropyl fluorophosphonate (DFP), 2-chloroethylethylsulfide (2CEES), cyanogen chloride (CNCl), and hydrogen cyanide (HCN). The type of chemical warfare agents, specifically, whether it was a nerve agent, blister agent, blood agent, or choking agent, could be determined by measuring the quantities of the monatomic ions or CN(+) using mass spectrometry. It was possible to detect gaseous CWAs that could not be detected by a conventional mass spectrometer. The distribution of electron temperature in the plasma could be closely controlled by adjusting the input power of the microwaves used to generate the electron cyclotron resonance plasma, and the target compounds could be detected as molecular ions or fragment ions, enabling identification of the target agents. 相似文献