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531.
Dynamic response analysis of monorail bridges under moving trains and riding comfort of trains 总被引:4,自引:0,他引:4
Chang Hun Lee Chul Woo Kim Mitsuo Kawatani Nobuo Nishimura Takumi Kamizono 《Engineering Structures》2005,27(14):21-2013
This paper introduces an analytical procedure to derive equations of motion for the monorail train–bridge interaction based on Lagrange’s formulation to investigate riding comfort of moving monorail trains on bridges. A 15 degrees-of-freedom dynamic model is assumed for a car in a monorail train that consists of driving, steering, and stabilizing wheels. It is based on the finite element method for modal analysis using three-dimensional models for a monorail bridge. Dynamic behaviors of a rationalized monorail bridge with a simplified structural system are investigated in comparison with those of a conventional monorail bridge using the developed analytical method. The riding comfort of running trains on the rationalized monorail bridge based on ISO 2631 is estimated using 1/3 octave band spectral analysis. Observations indicate that a rational type bridge does not engender difficulties related to the riding comfort of the monorail train, even when considering the longest traveling time of passengers between terminals. 相似文献
532.
Kenji Matsubayashi Tadashi Goto Kyoko Togaya Ken Kokubo Takumi Oshima 《Nanoscale research letters》2008,3(7):237-241
The introduction of pin-up oxygen on C60, such as in the oxidized fullerenes C60O and C60On, induced noticeable increase in the antioxidant activity as compared to pristine C60. The water-soluble inclusion complexes of fullerenes C60O and C60On reacted with linoleic acid peroxyl radical 1.7 and 2.4 times faster, respectively.
相似文献
Ken KokuboEmail: |
533.
Akiyama T Yamazaki T Tanamoto K 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2011,52(1):40-46
The identification test for thickening polysaccharides containing neutral saccharides and uronic acids was investigated by GC analysis of constituent monosaccharides. The reported method, in which monosaccharides were converted to diethyldithioacetal derivatives with ethanethiol followed by trimethylsilylation, was improved in terms of operability and reproducibility of GC/MS analysis. The suitability of the improved diethyldithioacetal derivatization method was determined for seven thickening polysaccharides, i.e., carob bean gum, guar gum, karaya gum, gum arabic, gum ghatti, tragacanth gum and peach gum. The samples were acid-hydrolyzed to form monosaccharides. The hydrolysates were derivatized and analyzed with GC/FID. Each sugar derivative was detected as a single peak and was well separated from others on the chromatograms. The amounts of constituent monosaccharides in thickening polysaccharides were successfully estimated. Seven polysaccharides were distinguished from each other on the basis of constituent monosaccharides. Further examination of the time period of hydrolysis of polysaccharides using peach gum showed that the optimal times were not the same for all monosaccharides. A longer time was needed to hydrolyze glucuronic acid than neutral saccharides. The findings suggest that hydrolysis time may sometimes affect the analytical results on composition of constituent monosaccharides in polysaccharides. 相似文献
534.
Akiyama T Yamanaka M Date Y Kubota H Nagaoka MH Kawasaki Y Yamazaki T Yomota C Maitani T 《Shokuhin eiseigaku zasshi. Journal of the Food Hygienic Society of Japan》2002,43(6):348-351
A sensitive method for detecting bromate in bread by ion chromatography with inductively-coupled plasma mass spectrometry (IC/ICP-MS) was developed. Bromate was extracted from bread with water. The clean-up procedure included a 0.2 micron filter, a C18 cartridge for defatting, a silver cartridge to remove halogen anions, a centrifugal ultrafiltration unit to remove proteins, and a cation-exchange cartridge to remove silver ions. A 500 microL sample solution was applied to IC/ICP-MS. The detection limit and the quantitation limit of bromate in the solution were 0.3 ng/mL and 1.0 ng/mL, expressed as HBrO3, respectively, which corresponded to 2 ng/g and 5 ng/g, respectively, in bread. Recovery of bromate was about 90%, and the CV was about 2%. Based on the detection limit in solution and recovery from bread, the detection limit of bromate in bread was estimated to be 2 ng/g. 相似文献
535.
Tanino T Ito T Ogino C Ohmura N Ohshima T Kondo A 《Journal of Bioscience and Bioengineering》2012,114(2):209-211
Four kinds of transporters, HXT1 and HXY7 from Saccharomyces cerevisiae, and GXF1 and GXS1 from Candida intermedia, were overexpressed in xylose-metabolizing S. cerevisiae harboring a xyloseisomerase-based pathway. Overexpression of transporter enhanced sugar consumption and ethanol production, and GXF1 was efficient for ethanol fermentation from both glucose and xylose. 相似文献
536.
Tetsuyuki Ishii Takumi Takashima Kenji Otani 《Progress in Photovoltaics: Research and Applications》2011,19(2):170-179
Various kinds of photovoltaic (PV) modules have been developed and practically operated as PV systems up to present. Investigation of the long‐term reliability of PV modules is indispensable for the use of PV systems as reliable energy sources. In this study, we show the results of outdoor exposure test in which the performance of 14 PV modules composed of five different kinds made by six different PV manufacturers have been measured since July 2004. The average performance is calculated in each year from 2005 to 2008, and the performance degradation is quantitatively evaluated. The results are that the magnitude of the performance degradation can be clearly classified by the kinds of the PV modules. The performance difference of the single‐crystalline silicon (sc‐Si) modules between 2005 and 2008 is from 1.9% to 2.8%. Polycrystalline silicon (pc‐Si) modules show performance degradation from 0.7% to 1.4%. The performance of an amorphous silicon/crystalline silicon (a‐Si:H/c‐Si) decreased by 0.7%. Although a pair of a‐Si modules had been already exposed to sunlight for about 6 months, the pair of modules show 4.4% of performance degradation. More than half of the performance degradation happened during the initial period from 2005 to 2006. This indicates that it takes about 2 years until the performance of a‐Si modules is stable. The performance is quite stable after 2006. Interestingly, the performance of the cupper indium gallium diselenide modules in 2008 is about 0.8% higher than that in 2005. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
537.
Keisuke Sasaki Michiyo Motoyama Jumpei Yasuda Tadashi Yamamoto Mika Oe Takumi Narita Mai Imanari Shinobu Fujimura Mitsuru Mitsumoto 《Meat science》2010
‘Tenderness’ has been an important sensory characteristic for beef, although ‘tenderness’ has not been commonly defined. On the other hand, ISO5492:1992 provides internationally established vocabularies for sensory analysis with simple definition. The aim of this study was texture characterization for three beef muscles cooked to four end-point temperatures using ISO5492:1992 texture terms in Japanese to develop objective sensory evaluation terms for beef texture other than ‘tenderness.’ Longissimus, semitendinosus, and psoas major muscles harvested from three Holstein steers were cooked to 45, 60, 72, and 92 °C end-point temperatures and evaluated by a trained sensory panel. Correspondence analysis indicated that the ‘chewiness’ and ‘hardness’ defined in ISO5492 were distinguished in each muscle. Changes in the ‘chewiness’ and ‘hardness’ qualities during cooking were different from each other. These findings suggest that both ‘chewiness’ and ‘hardness’ as defined in ISO5492:1992 should be evaluated simultaneously to determine the sensory texture of beef. 相似文献
538.
In recent years, IP networks have become increasingly complex and the range of network applications has widened. As a result,
the need for experimental evaluation of application performance has increased. We introduce a measurement‐based performance
evaluation method that combines a function to generate various patterns of application traffic with one to measure end‐to‐end
network performance at the application level. For our method, we also propose traffic models of various applications that
can represent the characteristics of these applications, for example, the burstiness of traffic. This method has already been
implemented as a benchmarking tool on UNIX operating systems.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
539.
Takuya Fukahori Takumi Tokiyoshi Toshihide Igari Yasuharu Chuman Nobuyoshi Komai 《Energy Materials: Materials Science and Engineering for Energy Systems》2017,12(3):194-207
Utilising the random-fracture-resistance model of grain boundaries, micro-macro combined creep damage simulation was applied to the prediction of the distribution of small defects in the FGHAZ (fine-grained heat-affected zone) of longitudinal welds in an actual-size elbow of modified 9Cr-1Mo (9Cr-1MoVNb) steel subject to internal pressure at 923 K. Based on the simulation results, a prediction scheme for the final rupture life of welds was considered using the damage mechanics concept together with effective stress. The applicability of nonlinear fracture mechanics was also discussed, assuming the initial crack length determined from the microscopic simulation results. The results thus obtained are summarized as follows: As the simulation results showed, the peaks of small defect density in the subsurface could be predicted, corresponding well with the observed results. Final failure life prediction based on the damage mechanics concept was found to be applicable, by considering both the final failure surface connecting the weakest grain boundaries and the effective stress against this surface. The fracture mechanics approach was also found applicable when assuming the initial crack length from the high peaks of the simulated small defects in the last stage of creep life. 相似文献
540.
Akihiro Matsuyama Hironori Mizutani Takumi Kozuka Hiroshi Inoue 《International Journal of Hydrogen Energy》2017,42(35):22622-22627
Crystal structure and electrochemical properties of the Zr1?xTixNi (0.05 ≤ x ≤ 0.5) alloys were investigated. X-ray diffraction spectra showed that the primary phase of all Zr1?xTixNi alloys had the B33-type orthorhombic crystal structure, which was characteristic of ZrNi, and the unit cell volume of the primary phase linearly decreased with an increase in the x value. In the charge–discharge tests with the Zr1?xTixNi alloy negative electrodes, the initial discharge curves for the alloys with x ≥ 0.3 had two plateaus. Both plateau potentials negatively shifted with an increase in the x value. The initial discharge capacity for the Zr0.6Ti0.4Ni alloy negative electrode was 349 mAh g?1 at 25 mA g?1 and 333 K, which was the highest in this study. The high-rate dischargeability and cycle performance were also improved by the partial replacement of Zr by Ti. 相似文献