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131.
Masami Kurano Masami Yasuda Jun-Ichi Nakagami Yuji Yoshida 《Fuzzy Optimization and Decision Making》2004,3(4):367-374
Stimulated by Zadeh's paper (Journal of Statistical Planning and Inference,2002, 105, 233--264), we will try to consider a perceptive analysis of the optimal stopping problem. In this paper, the fuzzy perception value of the expectation of the optimal stopped reward is characterized and calculated by a new recursive equation. Also, a numerical example described by triangular fuzzy numbers is given. 相似文献
132.
Hiroshi Tabata Kinya Kumazawa Masami Funakawa Jun-ichi Takimoto Makio Akimoto 《Optical Review》1996,3(2):139-145
This paper describes the mechanism generating the beautiful wing colors of various male butterflies and the relationship between the wing material and the color appearance. The microstructure of the scales covering the upper surface of the wings was analyzed with the aid of a scanning electron microscope. The basic mechanism of color generation of structurally colored scales is determined for the first time in accordance with the theory of optical interference in thin film layers using a model of wing scales. Optical properties were found in relation to the three-dimensional spectral reflectance of the samples, and differences were observed between the brightness perceived in subjective evaluations and calculated values based on the reflective spectra of the structurally colored wings. The results of this study suggest that the microroughness of the upper wing surface may influence the perceived gloss of structurally colored wings. 相似文献
133.
134.
T Nagatomo J Aono A Tajiri T Nakamura H Tsuchihashi 《Chemical & pharmaceutical bulletin》1988,36(3):1122-1127
135.
H. Ohde S. Lin A. Minoh F. O. Shimizu M. Aono T. Suzuki 《Applied physics. B, Lasers and optics》1996,62(1):15-19
A down-conversion to the mid-infrared region by using Stimulated Electronic Raman Scattering (SERS) in potassium vapor is described. The pump radiation is a frequency-doubled regeneratively amplified Ti:Sapphire laser with a pulse duration of 2 ps, pulse energy of 0.2 mJ, and repetition rate of 10 Hz. With the pumping frequency tuned around the potassium 4s-5p transition, nearly transform-limited infrared radiation tunable between 2.2 and 3.4 m has been generated with a peak infrared energy of 12 µJ, corresponding to a quantum efficiency of 17%, and with a pulse duration of 2 ps. The present tuning range could be extended by extending the tuning range of the pump laser. In comparison, intense infrared radiation of 90 µJ energy but with a very narrow tunability around 2.9 m has also been generated by SERS in barium vapor. 相似文献
136.
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
137.
Y Kohno Y Hiraki Y Takeda S Awai K Murakami T Noriyasu M Yamamoto K Aono Y Nakata 《Radioisotopes》1988,37(6):325-329
Xenon-133 ventilation study were used to measure regional ventilation in seven patients with pulmonary sarcoidosis and in four normal subjects. For the purpose of analyzing the washout curves on the whole lungs, two ventilation indexes were calculated, which were TA/H and T1/2. TA/H is that the area under the curve divided by the difference in mean count rate during equilibrium and at 120 s after washout started. T1/2 value represents the time required to 50% of the mean count rate during equilibrium. The average time of TA/H on the whole lung was 13.5 +/- 1.1 s in normal subjects (n = 4), 13.0 +/- 4.3 s in stage I (bilateral hilar lymphadenopathy without lung involvement on chest X-ray) sarcoidosis (n = 3), 21.3 +/- 1.8 s in stages I, II (lung involvement) sarcoidosis (n = 4). The average time of T1/2 on the whole lung was 43.7 +/- 4.7 s in normal subjects, 42.3 +/- 16.0 s in stagel sarcoidosis, 72.5 +/- 28.6 s stages II, III sarcoidosis. The ventilation indexes on the regional lungs showed almost a similar tendency to that on the whole lung. The ventilation indexes in patients with stage II, III sarcoidosis were significantly longer than in normal subjects and in patients with stage I sarcoidosis. It was suggested that 133Xe washout test might detect regional ventilation abnormalities which were not recognized on chest X-ray in pulmonary sarcoidosis. 相似文献
138.
Takehiko Nishio Megumi Tabata Hiroyuki Koyama Masami Sakamoto 《Helvetica chimica acta》2005,88(1):78-86
The photochemical reactions of various ‘N‐methacryloyl acylanilides’ (=N‐(acylphenyl)‐2‐methylprop‐2‐enamides) have been investigated. Under irradiation, the acyl‐substituted anilides 1a – 1c and 1o afforded exclusively the corresponding quinoline‐based cyclization products of type 2 (Table 1). In contrast, irradiation of the benzoyl (Bz)‐substituted anilides 1e – 1h afforded a mixture of the open‐chain amides 4e – 4h and the cyclization products 2e – 2h . Irradiation of the para‐acyl‐substituted anilides 6a – 6e and 6h afforded the corresponding quinoline‐based cyclization products of type 5 as the sole products (Table 2). The formation of the cyclization products 2a – 2c and 2o can be rationalized in terms of 6π‐electron cyclization, followed by thermal [1,5] acyl migration, and that of compounds 3p, 5a – 5e , and 5h can be explained by a 6π‐electron cyclization only. The formation of the open‐chain amides 4e – 4h probably follows a mechanism involving a 1,7‐diradical, C and a spirolactam of type D (Scheme). Long‐range ζ‐H abstraction by the excited carbonyl O‐atom of the benzoyl group on the aniline ring is expected to proceed via a nine‐membered cyclic transition state, as proposed on the basis of X‐ray crystallographic analyses (Fig. 2). 相似文献
139.
Seiki Saito Norio Bunya Masami Inaba Toshio Moriwake Sigeru Torii 《Tetrahedron letters》1985,26(43):5309-5312
Chiral β-hydroxy-α-amino acids such as erythro-β-hydroxy-L-aspartic acid and erythro-β-hydroxymethyl-L-serine derivatives have been synthesized in optically pure form from L- and D-tartaric acids through a novel oxirane ring-opening reaction and a selective reduction of α-hydroxy ester as key steps. 相似文献
140.
Kyung‐Youl Baek Masami Kamigaito Mitsuo Sawamoto 《Journal of polymer science. Part A, Polymer chemistry》2002,40(5):633-641
Various star‐shaped copolymers of methyl methacrylate (MMA) and n‐butyl methacrylate (nBMA) were synthesized in one pot with RuCl2(PPh3)3‐catalyzed living radical polymerization and subsequent polymer linking reactions with divinyl compounds. Sequential living radical polymerization of nBMA and MMA in that order and vice versa, followed by linking reactions of the living block copolymers with appropriate divinyl compounds, afforded star block copolymers consisting of AB‐ or BA‐type block copolymer arms with controlled lengths and comonomer compositions in high yields (≥90%). The lengths and compositions of each unit varied with the amount of each monomer feed. Star copolymers with random copolymer arms were prepared by the living radical random copolymerization of MMA and nBMA followed by linking reactions. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 633–641, 2002; DOI 10.1002/pola.10145 相似文献