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61.
Power reduction of micro‐electro‐mechanical system shutter display by temporal smoothing of image signal 下载免费PDF全文
Power reduction technique for micro‐electro‐mechanical system (MEMS) shutter display employing a time‐division pulse‐width‐modulation gray scale expression method has been proposed. By temporally smoothing the column data signal, transition frequency between open and closed states of the MEMS shutter decreases, resulting in power reduction. In order to suppress color distortion due to the smoothing, the number of smoothing subfield is limited. In addition, the number of smoothing subfield is adjusted for each pixel after calculating color difference between the original and smoothed pixels. Simulated experiments show about 20% reduction of the transition number of MEMS shutter state when the color‐difference tolerance is 0.8 and the maximum number of smoothing subfield is 3. 相似文献
62.
Okura Fumio Akaguma Takayuki Sato Tomokazu Yokoya Naokazu 《Multimedia Tools and Applications》2017,76(2):2671-2695
Multimedia Tools and Applications - Indirect augmented reality (IAR) employs a unique approach to achieve high-quality synthesis of the real world and the virtual world, unlike traditional... 相似文献
63.
Fumikazu Akamatsu Tomokazu Hashiguchi Yukari Igi Hanae Izu Tsutomu Fujii 《Food Analytical Methods》2017,10(8):2792-2799
Carbon stable isotope analysis of ethanol is an established method for determining the authenticity of alcoholic beverages, but there is no accepted method for measurements of glucose carbon stable isotopic composition (δ 13C). This study aims to establish two methods to determine accurately the δ 13C value of glucose isolated from sake by high-performance liquid chromatography (HPLC) after three clean-up steps using ion exchange chromatography and in simple freeze-dried sake (total nonvolatile matter) and to examine two methods that yield different δ 13C values. In the glucose isolation procedure, the δ 13C values of glucose were not significantly affected by the glucose concentration, solvent (water or aqueous acetonitrile), drying method (freeze-dry or nitrogen-spraying), the clean-up step using ion exchange chromatography (weakly acidic cation-exchange, strongly acidic cation-exchange, and weakly basic anion-exchange resins), or HPLC isolation. Glucose nitrogen spray-dried after isolation by ion exchange chromatography and HPLC showed a carbon isotope discrimination value of <0.1 ‰. The glucose δ 13C values ranged from ?26.8 to ?25.5 ‰ in authentic sake and from ?27.0 to ?11.0 ‰ in commercial sake samples. This HPLC isolation approach may provide a first step toward visualizing the brewing process via isotopic carbon flow during fermentation. Additionally, there was no significant difference between the δ 13C values of glucose and total nonvolatile matter from sake. The δ 13C measurement of simple freeze-dried sake can substitute for glucose δ 13C measurement using HPLC isolation, thus aiding high-throughput detection of carbon derived from C4 plants in sake. 相似文献
64.
Tomokazu Yoshimura Yasuhiro Kiridoshi Yoshifumi Koide Hideto Shosenji Kunio Esumi 《Journal of surfactants and detergents》2002,5(2):159-164
N-(α-Carboxyalkyl)acrylamide telomer-type surfactants (xC
n−1
AmAc where n is alkyl chain length=6, 8, 10, 12; and x is degree of polymerization=3.3–13.1) were synthesized by the telomerization of monomer (C
n−1
AmAc) in the presence of the corresponding alkanethiol as a chain transfer agent and then investigated for their surface-active
properties. xC
n−1
AmAc telomers lowered the surface tension of aqueous solutions that were at pH 9–10. The critical micelle concentrations (CMC)
of the telomers were lower than those of the monomers with the same alkyl chain length, and the CMC values shifted to lower
concentrations with both increasing alkyl chain length and polymerization degree. xC9AmAc with x=3.3–6.3 gave the highest efficiencies in lowering the surface tension. The cross-sectional molecular areas per molecule of
xC
n−1
AmAc telomers were smaller than the values estimated on the assumption that they are assemblies of C
n−1
AmAc monomer units. The foaming abilities and the foam stabilities were both in the orders of xC7AmAc>xC9AmAc>xC5AmAc>xC11AmAc. Mixtures of aqueous solutions of xC
n−1
AmAc telomers and toluene formed oil-in-water emulsions. The emulsion-stabilizing abilities were in the orders of xC7AmAc>xC5AmAc>xC9AmAc=xC11AmAc. The addition of Ca2+ to the mixed solutions of telomers and toluene resulted in formation of water-in-oil type emulsions. Thus, the surface-active
properties of the telomers were influenced significantly by the alkyl chain length and the polymerization degree of the telomers.
In addition, these properties could be correlated with the hydrophilic-lipophilic balance (HLB); the highest surface activities
were observed by using xC
n−1
AmAc with HLB of 14–18. 相似文献
65.
Tomokazu Umeyama Kensuke Naka Mia D. Bravo Akiko Nakahashi Yoshiki Chujo 《Polymer Bulletin》2004,52(3-4):191-199
Summary
Cross-linked poly(vinylene-arsine)s (4) were synthesized by a free-radical terpolymerization of phenylacetylene (2), hexaphenylcyclohexaarsine (l), and p- or m-diethynylbenzene (p- or m-3) at different compositions in the presence of a catalytic amount of AIBN. The number-average molecular weights of the resulting polymers were a few thousands estimated by gel permeation chromatography (GPC) analysis. By gas chromatography (GC) analysis p-3 was found to be more reactive during the polymerization than m-3 and the resulting cross-linked polymer (p-4) showed lower solubility than that of m-4. The cross-linked poly(vinylene-arsine)s showed higher glass transition temperature in the measurement of differential scanning calorimetry (DSC) and more red-shifted emission in chloroform solution than that of the linear poly(vinylene-arsine). These properties could be tuned by varying the monomer feed ratio. 相似文献
66.
Kosuke InoAuthor VitaeAtsuko IshidaAuthor Vitae Kumi Y. InoueAuthor VitaeMasato SuzukiAuthor Vitae Masahiro KoideAuthor Vitae Tomoyuki YasukawaAuthor VitaeHitoshi ShikuAuthor Vitae Tomokazu MatsueAuthor Vitae 《Sensors and actuators. B, Chemical》2011,153(2):468-473
We have developed an electrorotation (ER) chip that has a sandwich structure in which interdigitated array (IDA) electrodes are arranged face-to-face. These IDA electrodes on the top and bottom of the chip were orthogonally arranged to form over 2000 square regions having rotating electric fields between the IDA electrodes. Since rotating electric fields can be generated by arranging the electrical connections to produce a π/2 phase difference between adjacent electrodes, a large number of measurement areas for ER were incorporated within a single ER chip. The ER properties of glass microrods at the individual measurement areas were investigated using this ER chip. The present ER chip was found to be a useful tool for performing high-throughput assays to analyze the dielectric properties of microparticles. 相似文献
67.
Yamanaka T Aso I Togashi S Tanigawa M Shoji K Watanabe T Watanabe N Maki K Suzuki H 《Water research》2002,36(10):2636-2642
Not only sulfur-oxidizing bacteria but also an acidophilic iron-oxidizing bacterium (or bacteria) were found in the corroded concrete from several sewerage systems in Japan. The surface pH of concrete test piece exposed to an atmosphere containing hydrogen sulfide of the concentrations more than 600 ppm in the systems was usually below 2 after a month. This was attributable to ability of the sulfur-oxidizing bacteria to grow in the thin water layer which contained hydrogen sulfide and covered the piece even when the surface pH of concrete was 12-13. When the sulfuroxidizing bacteria grew in the surface of concrete and produced sulfuric acid, the pH of the inner parts of concrete was lowered where the bacteria were hardly found. Probably, sulfuric acid formed by the bacteria in the surface parts penetrated into the inner parts. The different species of sulfur-oxidizing bacteria were found in different sewerage systems. The growth of the sulfur-oxidizing and acidophilic iron-oxidizing bacteria was completely inhibited by formates, especially by calcium formate of concentrations more than 50 mM. Calcium formate can protect concrete in sewerage systems from bacterial corrosion. 相似文献
68.
69.
70.
Omachi S. Inoue M. Aso H. 《IEEE transactions on pattern analysis and machine intelligence》2001,23(3):315-322
Decorated characters are widely used in various documents. Practical optical character reader is required to deal with not only common fonts but also complex designed fonts. However, since the appearances of decorated characters are complicated, most general character recognition systems cannot give good performances on decorated characters. In this paper, an algorithm that can extract character's essential structure from a decorated character is proposed. This algorithm is applied in preprocessing of character recognition. The proposed algorithm consists of three procedures: global structure extraction, interpolation of structure and smoothing. By using multiscale images, topographical features, such as ridges and ravines are detected for structure extraction. Ridges are used for extracting global structure and ravines are used for interpolation. Experimental results show character structures can be clearly extracted from very complex decorated characters 相似文献