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91.
Yasunori Igasaki Fanghong Li Narihiro Yoshida Haruyoshi Toyoda Takashi Inoue Naohisa Mukohzaka Yuji Kobayashi Tsutomu Hara 《Optical Review》1999,6(4):339-344
To realize a high efficiency electrically addressable phase-only modulator, we have coupled a liquid crystal display (LCD) to an optically addressed parallel-aligned nematic liquid crystal spatial light modulator (PAL-SLM) with a set of lenses. Phase modulation exceeding 3ϖ at 532 nm wavelength was obtained. We obtained linear transfer characteristics for phase modulation at various desired phase levels after calibration and adjustment of the transfer characteristics of the PAL-SLM and the LCD. Diffraction efficiency of 40% for binary phase grating and of 90% for 8-level blazed phase grating, which were very close to the simulation values, were observed. The power loss of the readout light was caused when passed through a half mirror, therefore, we examined a setup using an oblique readout light at the modulator. Very high diffraction efficiency was obtained from the setup by optimizing the polarization direction and optical path for this light, and the orientation of liquid crystals. Since the modulator can perform at better than 90% diffraction efficiency and at nearly 100% reflectivity, various high efficiency systems utilizing such modulators are expected. 相似文献
92.
Yasunori Fujikoshi Takashi Kanda Megu Ohtaki 《Annals of the Institute of Statistical Mathematics》1999,51(4):707-721
This paper deals with some inferential problems under an extended growth curve model with several hierarchical within-individuals design matrices. The model includes the one whose mean structure consists of polynomial growth curves with different degrees. First we consider the case when the covariance matrix is unknown positive definite. We derive a LR test for examining the hierarchical structure for within individuals design matrices and a model selection criterion. Next we consider the case when a random coefficients covariance structure is assumed, under certain assumption of between-individual design matrices. Similar inferential problems are also considered. The dental measurement data (see, e.g., Potthoff and Roy (1964, Biometrika, 51, 313-326)) is reexamined, based on extended growth curve models. 相似文献
93.
94.
Hongyuan Wang Toshinari Ugomori Yong Wang Kazuhiro Tanaka Hidetoshi Kita Ken‐Ichi Okamoto Yasunori Suma 《Journal of Polymer Science.Polymer Physics》2000,38(13):1800-1811
Poly(ethylene oxide imide) segmented copolymer (PEO‐PI) membranes were crosslinked by the chemical reaction between ethylene glycol diglycidyl ether and benzylalcohol groups of diamine moieties in polyimide segments at high temperatures. Sorption and diffusion of penetrants took place in poly(ethylene oxide) segment microdomains. Sorption and desorption behavior of pure vapors such as benzene (Bz), cyclohexane (Cx) and n‐hexane (Hx) was classified as the Fickian diffusion. Sorption isotherms of binary liquid mixtures could be represented by the Flory–Rehner model, but the model overpredicted the sorption amounts of Cx and Hx, leading to small predictions of sorption selectivity αS for Bz/Cx and Bz/Hx systems. UNIFAC‐FV model fairly well predicted the sorption amounts of aromatic hydrocarbons, but significantly overestimated those of nonaromatic ones, leading to too small predictions of αS. Pervaporation (PV) behavior of PEO‐PI membranes was governed by sorption behavior followed by membrane swelling. Diffusion coefficient weakly depended on the minimum cross section of a penetrant. The diffusivity selectivity αD hardly depended on the feed composition and was about 1.4 and 0.75 for Bz/Cx and Bz/Hx, respectively. PV selectivity αPV was larger for Bz/Hx than for Bz/Cx because of larger αS. PEO‐PI membranes displayed high specific permeation flux Ql and reasonably high αPV for aromatic/nonaromatic hydrocarbons; for example, Ql = 60 Kg μm/(m2 h) and αPV = 8 for a feed mixture containing Bz, Tol, Hx, n‐Ot and i‐Ot of 20 wt % at 353 K. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 1800–1811, 2000 相似文献
95.
96.
Yasunori Fujikoshi Takafumi Noguchi Megu Ohtaki Hirokazu Yanagihara 《Annals of the Institute of Statistical Mathematics》2003,55(3):537-553
This paper is concerned with cross-validation (CV) criteria for choice of models, which can be regarded as approximately unbiased
estimators for two types of risk functions. One is AIC type of risk or equivalently the expected Kullback-Leibler distance
between the distributions of observations under a candidate model and the true model. The other is based on the expected mean
squared error of prediction. In this paper we study asymptotic properties of CV criteria for selecting multivariate regression
models and growth curve models under the assumption that a candidate model includes the true model. Based on the results,
we propose their corrected versions which are more nearly unbiased for their risks. Through numerical experiments, some tendency
of the CV criteria will be also pointed. 相似文献
97.
98.
Minoru Isobe Yasunori Funabashi Yoshiyasu Ichikawa Shigeru Mio Toshio Goto 《Tetrahedron letters》1984,25(19):2021-2024
A stereoselective synthesis of both syn- and anti-diastereoisomers (3 and 4) was established by a method involving heteroconjugate addition, as the key step, with various nucleophiles such as alkoxyvinyllithiums which can be functionalized after the addition. Two examples with aliphatic and carboxylic groups are demonstrated in high specificity. 相似文献
99.
Masao Kawai Tooru Taga Yoshihisa Miwa Yasuo Butsugan 《Journal of chemical crystallography》1992,22(2):131-137
(25R)-2,3,25,27-Tetrahydrophysalin A dimethanol solvate, C30H42O12, a derivative of 13,14-seco-16,24-cyclosteroid physalin A, crystallizes in the orthorhombic space groupP212121, witha=15.486(5),b=14.794(4), 12.248(6) Å andZ=4. The crystal structure has been solved by direct methods, and refined to an R-value of 0.053 for 2345 observed reflections.1H NMR spectral data of physalin A and its hydrogenated derivatives measured in dimethylsulfoxide-d6 solutions have been elucidated, based on the crystal structure of the tetrahydrophysalin A, enabling the assignment of all the proton signals of physalin A. The-proton of C(11)-methylene has been shown to resonate at remarkably higher field due to anisotropic shielding effect of carbonyl group at C(15). 相似文献
100.
A method for the determination of copper(II) complexes with humic acids was developed by batch operation with the cation exchanger sulphopropyl-Sephadex C-25 (C-25). The copper-binding ability (conditional stability constants and copper-complexing capacities) of humic acids which were extracted from peat in Hokkaido was evaluated. A solution containing copper(II) ions and humic acids was shaken with the C-25 exchanger. The copper-humic acid complexes remained in the supernatant and the uncomplexed free copper ion was retained on the C-25. The copper-humic acid complexes were determined by flame atomic absorption spectrometry. The copper-binding ability of nitrilotriacetic acid (NTA) as a model ligand was similarly determined with a Scatchard plot. The conditional stability constant obtained at pH 4.5 was in good agreement with the reported value. The copper-binding abilities of the humic acids from peat were estimated using a Scatchard plot adopting a two-site model. The functional groups in the humic acids which contribute to the complexation with copper were investigated by conductimetric and pH titration, and the relationship between the copper-binding sites and functional groups in the humic acids was investigated. 相似文献