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981.
Yoichi Kageyama Hiromichi Kameya Makoto Nishida Chikako Ishizawa 《IEEJ Transactions on Electrical and Electronic Engineering》2013,8(Z1):S88-S94
A method to recognize speed limit signs in night scene images is proposed in this paper. The proposed method involves two main stages. First, sign candidates are detected by using the outline of white domain on the signs. This region has little influence on the change of color information or size. Next, the feature and common parts in speed limit signs are distinguished on the basis of their layout. We extract a suitable label from sign candidates and recognize it as a sign through a matching experiment. Experimental results for 596 images show that the proposed method is able to recognize speed limit signs with an accuracy of 94.3%. It is also shown that 423 images without speed limit signs are perfectly distinguished as images having no speed limit signs. © 2013 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
982.
Ammonium nitrate (AN)‐based composite propellants have several major problems, namely, a low burning rate, poor ignitability, low energy, and high hygroscopicity. The addition of a burning catalyst proved to be effective in improving the burning characteristics of AN‐based propellants. In this study, the burning characteristics of AN‐based propellants supplemented with MnO2 as a burning catalyst were investigated. The addition of MnO2 is known to improve the ignitability at low pressure. The most effective amount of MnO2 added (ξ) for increasing the burning rate is found to be 4 %. The increasing ratio with ξ is virtually independent of the burning pressure and the AN content. However, the pressure exponent unfortunately increased by addition of MnO2. The apparent activation energy of the thermal decomposition for AN and the propellant is decreased by addition of MnO2. From thermal decomposition kinetics it was found that MnO2 could accelerate the thermal decomposition reaction of AN in the condensed phase, and therefore, the burning characteristics of the AN‐based propellant are improved. 相似文献
983.
Bon Ju Gu Wang Hoon Lee Kazuaki Sawada Makoto Ishida 《IEEJ Transactions on Electrical and Electronic Engineering》2012,7(3):337-341
This paper presents a low‐power radio frequency (RF) transmitter using dual‐pulse position modulation (DPPM) for a smart micro‐sensing chip (SMSC) with sensors and large scale integrated circuit (LSI) on the same chip. The DPPM method is presented by a fixed pulse and a variable pulse within the same time frame. The distance between the fixed pulse and the variable pulse describes the amplitude of the input signal. A modulator and a ring oscillator were designed for the RF transmitter using the DPPM method. In the modulator, the pulse width modulation (PWM) signal is generated by the intersective method, and narrow pulses are extracted at the rising and falling positions of the generated PWM signal. The designed oscillator has the function of an oscillation controller. The RF transmitter was fabricated with sensors for an SMSC by complementary metal–oxide–semiconductor (CMOS) technology. The power consumption of the fabricated modulator was 4.5 mW. The power consumption of the proposed RF transmitter was measured as 7.0–7.3 mW at an input signal of 0.8–2.5 V. The RF transmitter using the DPPM method was able to reduce the power consumption by a maximum of 50.3% compared to a transmitter using the PWM method, because in the latter the dissipated power was 8.4–14.5 mW at the same input signal. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
984.
Hideharu Mori Yosuke Saito Eri Takahashi Kazuhiro Nakabayashi Atsuhiko Onuma Makoto Morishima 《Polymer》2012,53(18):3861-3877
Four vinyl sulfonate ester derivatives, methyl ethenesulfonate (MES), ethyl ethenesulfonate (EES), 2,2,2-trifluoroethyl ethenesulfonate (TFES), and 2,2,2-trichloroethyl ethenesulfonate (TCLES), which are protected forms of vinyl sulfonic acids, were polymerized by reversible addition-fragmentation chain transfer (RAFT) polymerization. Polymers having relatively narrow molecular weight distributions and pre-determined molecular weights were obtained by the polymerization of all monomers using a suitable xanthate-type chain transfer agent (CTA). The RAFT polymerizations of EES and TCLES were found to proceed in controlled fashions under suitable conditions, as confirmed by the formation of narrow polydispersity products, molecular weights controlled by the monomer/chain transfer agent ratio, and linear increases in molecular weight with conversion. Deprotection of the ethyl group of poly(EES) by LiBr in refluxing 2-butanone proceeded smoothly to give water-soluble poly(lithium vinyl sulfonate). Poly(potassium vinyl sulfonate) was also obtained by the deprotection of poly(TCLES) using potassium tert-butoxide. The syntheses of thermoresponsive block copolymers involving poly(lithium vinyl sulfonate) segments were conducted by RAFT polymerization of N-isopropylacrylamide using poly(EES) macro-CTA, followed by deprotection. The thermally-induced phase separation behavior and assembled structures of the block copolymers were also studied in aqueous solution. 相似文献
985.
Nansai K Oguchi M Suzuki N Kida A Nataami T Tanaka C Haga M 《Environmental science & technology》2012,46(9):4933-4940
Heavy metals like mercury that are emitted into the environment remain there indefinitely, posing a long-term threat to both the environment and human health. Elemental mercury is volatile and is in gaseous form, and because of the long residence time, transported over long distances. Comprehensive control of mercury emissions therefore remains an important international issue. The crucial steps for designing effective approaches for such control include the quantification of mercury emissions by sources and the identification of geographical characteristics of the emissions. In this study a detailed, high-resolution inventory of Japanese mercury emissions in 2005 was developed to improve understanding of their geographical distribution. Proceeding from a national emissions inventory per source category, emissions were spatially allocated with increasing geographical resolution in a stepwise procedure using statistics from geographic information resources, yielding mercury emissions per prefecture, per municipality and per grid cell of approximately 1 × 1 km. The five prefectures with the highest emissions were Fukuoka, Yamaguchi, Hyogo, Oita, and Hokkaido, accounting for 35.2% of all emissions. In each prefecture a small number of municipalities account for a major share of emissions. Distribution by grid cell is characterized by a concentration of 50% of all emissions in a mere 32 of the 255?954 grid cells over which emissions are distributed in this study. It was also quantitatively confirmed that use of larger grid cells leads to greater uncertainty in emissions distribution. Problems with data collection are clarified and measures to improve the accuracy of future estimation are proposed. 相似文献
986.
Asami Nakamura Akiyuki Hamasaki Sachihiko Goto Masaru Utsunomiya Makoto Tokunaga 《Advanced Synthesis \u0026amp; Catalysis》2011,353(6):973-984
An irreversible hydrolysis reaction of allyl esters ( 1 ) into carboxylic acids ( 2 ) and propanal ( 3 ) was achieved with a ruthenium/palladium (Ru/Pd) dual catalyst system. The optimized catalysts consists of a 1:1:1 mixture of (cyclopentadienyl)tris(acetonitrile)ruthenium hexafluorophosphate {[RuCp(MeCN)3] PF6}, bis(acetonitrile)palladium dichloride [PdCl2(MeCN)2] and 1,6‐bis(diphenylphosphanyl)hexane (DPPHex). The reaction proceeds via isomerization of allyl esters to 1‐propenyl esters and hydrolysis of them to give 2 and 3 . The first isomerization step was virtually catalyzed by the Ru components and the second hydrolysis step was mainly catalyzed by the Pd components. The optimized bidentate phosphine (DPPHex) which has long alkylene chain effectively generates two vacant sites on the Ru centers by bridging coordination. When a chelating bidentate phosphine such as DPPE was employed, only one vacant site remained on the Ru center and resulted in a low activity. This chelating Ru complex of DPPE formed even in the presence of 2 equivalents of Ru or additional 1 equivalent of Pd. These differences in coordination behaviour between DPPHex and 1,2‐bis(diphenylphosphanyl)ethane (DPPE) cause the differences of the catalytic activity in the first step. The phosphine coordination to Pd center slightly decreases the activity of second hydrolysis step but which was compensated by the increasing of the stability of Pd. On the whole, the optimized Ru/Pd dual catalyst system exhibited good performances on the irreversible hydrolysis of allyl esters. 相似文献
987.
Koji Yonehara Yasuyuki Miyoshi Aki Tsukajima Takeo Akatsuka Makoto Saito 《Advanced Synthesis \u0026amp; Catalysis》2011,353(7):1071-1075
The methodology in this article is a palladium(II)/copper(II)‐ or palladium(II)‐catalyzed intermolecular cyclization of acrylic acid with alkenes to produce α‐methylene‐γ‐butyrolactone derivatives using molecular oxygen as an environmentally benign oxidant. In this system, the carboxylato, especially trifluoroacetato, or trimethylacetato ligand, plays a quite important role to afford a high catalytic activity by suppressing the deposition of palladium(0) black. 相似文献
988.
Makoto Izumiya Miyu Haniu Katsuya Ueda Haruka Ishida Chuang Ma Hirokazu Ideta Atsushi Sobajima Koki Ueshiba Takeshi Uemura Naoto Saito Hisao Haniu 《International journal of molecular sciences》2021,22(14)
Many biomaterials have been evaluated using cultured cells. In particular, osteoblast-like cells are often used to evaluate the osteocompatibility, hard-tissue-regeneration, osteoconductive, and osteoinductive characteristics of biomaterials. However, the evaluation of biomaterial osteogenesis-inducing capacity using osteoblast-like cells is not standardized; instead, it is performed under laboratory-specific culture conditions with different culture media. However, the effect of different media conditions on bone formation has not been investigated. Here, we aimed to evaluate the osteogenesis of MC3T3-E1 cells, one of the most commonly used osteoblast-like cell lines for osteogenesis evaluation, and assayed cell proliferation, alkaline phosphatase activity, expression of osteoblast markers, and calcification under varying culture media conditions. Furthermore, the various media conditions were tested in uncoated plates and plates coated with collagen type I and poly-L-lysine, highly biocompatible molecules commonly used as pseudobiomaterials. We found that the type of base medium, the presence or absence of vitamin C, and the freshness of the medium may affect biomaterial regeneration. We posit that an in vitro model that recapitulates in vivo bone formation should be established before evaluating biomaterials. 相似文献
989.
Alberto Ferro Elena Gaio Manabu Takechi Makoto Matsukawa Luca Novello 《Fusion Engineering and Design》2013,88(9-10):1509-1512
The JT-60SA satellite tokamak will be built in Naka, Japan. One of the main aims of this machine is to achieve steady-state high-beta plasmas. To reach this result, passive stabilizing plate (SP) and resistive wall modes (RWM) active control system based on 18 in-vessel coils will be installed. In the present design, these coils are placed on the plasma side of the SP, behind the first wall. This solution maximizes the efficiency in producing fast magnetic fields into the plasma by minimizing the shielding effect of the passive structures. Then, if the power supply (PS) and the control system have sufficient dynamic performance, it is possible to control the RWM with very low magnetic fields. This allows minimizing the Ampere-turns and the power requested to control the RWM. Conversely, the very fast dynamics required represents one of the main issues for the design of the RWM control system. This paper, after having recalled the main specification data for the RWM control system deriving from the physics studies, describes the analyses performed to complete the set of requirements necessary for the PS design. The characterization of coils and feeders is shown and the voltage necessary to produce the required current and bandwidth is quantified. Possible connections among PS and coils are analyzed in order to achieve the highest possible flexibility in controlling the RWM with a reduced set of independent PS. Finally, considerations on reasonable voltage margins to cope with load uncertainties are given. 相似文献
990.
Makoto Nanko 《Science and Technology of Advanced Materials》2013,14(2):129-134
Oxidation behavior of ceramic matrix composites dispersed with metallic particles is discussed to establish materials design for high-temperature applications. Oxidation kinetics of ceramic matrix composites dispersed with metallic particles is understood from the viewpoint of the diffusion properties and defect chemistry of matrix oxides. High-temperature oxidation of Ni(p)/partially stabilized zirconia, Ni(p)/Al2O3 and Ni(p)/MgO was described as examples. 相似文献