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71.
In this paper we establish the exact solution for a hollow sphere with a rigid-plastic pressure-sensitive matrix and subjected to hydrostatic tension or compression. The matrix is assumed to obey to a parabolic Mises–Schleicher criterion. The closed-form expressions of the velocity field and of the stress field are provided. These exact solutions, expressed by means of the Lambert W function, allow to assess and discuss existing results. 相似文献
72.
Presently, many wind turbine generators (WTGs) are connected to the power grid. While the penetration of wind power to the power system is increasing, FIT price is decreasing. Therefore, wind generation companies want to increase the electric power output from wind farms (WFs). In this article, we propose a control technique to reduce the influence of the wake by changing a power coefficient of each WTG in a WF for the purpose of improving electric power output of WFs. We showed the optimization technique of a power coefficient of each WTG and the effect of reducing the influence of the wake using measurement data from WFs. In addition, we formulated the wake effect as a function of distance between WTGs. We verified 1% improvement of generated energy in a year compared to the conventional control method by simulation. Furthermore, we quantified the improvement of generated energy output, using the distance between WTGs and the occurrence rate of the direction of the wind as a variable. 相似文献
73.
Piezoresistivities of vapor‐grown carbon fiber/silicone foams for tactile sensor applications
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Due to the growing demand for tactile sensors, the possibility of detecting an external uniaxial pressure by the piezoresistive measuring of a conductive filler/elastomer composite was investigated. A series of piezoresistive models are discussed. Novel highly sensitive piezoresistive foams with excellent elasticity were fabricated using vapor‐grown carbon fiber (VGCF), two‐component silicone elastomer and a new type of thermally expandable micro beads foaming agent to overcome the disadvantages of the silicone elastomer in the utilization of a tactile sensor. Deformations of the foams caused by uniaxial pressure were observed using scanning electron microscopy from cross‐sections. Effects of the VGCF and the foaming agent on the piezoresistivitiy were investigated. The piezoresistive mechanisms of the foams are discussed according to the measurements, and good fit was found between the theoretical calculations and the experimental piezoresistivity measurements. It is found that the addition of the micro beads foaming agent can improve the piezoresistivity of the VGCF/silicone foam and increase the sensitivity and repeatability for its application in a tactile sensor. © 2016 Society of Chemical Industry 相似文献
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76.
K. Jonkers G. E. Derrick C. Lopez-Illescas P. Van den Besselaar 《Scientometrics》2014,101(2):1179-1194
This micro-level study explores the extent that citation analysis provides an accurate and representative assessment of the use and impact of bioinformatics e-research infrastructure. The bioinformatic e-research infrastructure studied offers common tools used by life scientists to analyse and interpret genetic and protein sequence information. These e-resources therefore provide an interesting example with which to explore how representative citations are as acknowledgements of knowledge in the life sciences. The examples presented here suggest that there is a relation between number of visits to these databases and number of citations; however, a parallel finding shows how citation analysis frequently underestimates acknowledged use of the resources offered on this e-research infrastructure. The paper discusses the implications of the findings for various aspects of impact measurement and also considers how appropriate citation analysis is as a measurement of knowledge claims. 相似文献
77.
Quantum discord is studied for two-qubit systems with different settings under the influence of the Bloch channel which is characterized by the longitudinal and transversal relaxation times and the environmental temperature. The relaxation of the quantum discord strongly depends on the ratio of the two relaxation times and the environmental temperature. It is found that the ratio of the quantum discord to the total correlation becomes finite or zero asymptotically, depending on the ratio of the relaxation times and the system setting. Furthermore, the optimal setting for sharing the quantum discord is discussed for given environmental temperature and ratio of the relaxation times. 相似文献
78.
Koizumi Hiroyasu Morio Naoki Ishikawa Alto Kondo Takumi 《Journal of Superconductivity and Novel Magnetism》2022,35(9):2357-2370
Journal of Superconductivity and Novel Magnetism - We theoretically study the superconductivity in hole-doped cuprate superconductors by employing a model composed of surface and bulk CuO $$_2$$... 相似文献
79.
Katsuki Hirabayashi Yoshiya Tashiro Nobuhiro Kondo Sachio Hayashi 《Journal of Applied Glycoscience》2017,64(2):33
We report production of the functional disaccharide gentiobiose β-D-Glcp-(1→6)-D-Glc by a hydrolysis reaction of hydrothermally treated Aureobasidium pullulans β-1,3-1,6-glucan as the substrate and Kitalase as the enzyme. Gentiobiose was produced over the pH range 4−6 and the concentration of gentiobiose produced decreased above pH 7. The maximum value of gentiobiose production was unaffected by the enzyme concentration. The maximum concentration of gentiobiose produced was dependent on the substrate concentration whereas the maximum ratio of gentiobiose to glucose was not. The production of gentiobiose from yeast β-1,3-1,6-glucan was lower than that from A. pullulans β-1,3-1,6-glucan. 相似文献
80.
Naoki Kawara Hisashi Kurachi Takafumi Seto Seiji Kamba Takashi Kondo 《Aerosol science and technology》2016,50(6):535-541
Metal screens with uniform micrometer-sized opening were employed to sieve aerosol particles by suppressing the adhesion of particles smaller than the openings. The collection efficiencies of monodispersed polystyrene latex (PSL) particles were experimentally determined using the metal screens with 1.2, 1.8, 2.5, and 4.2 μm openings at various filtration velocities. The particles smaller than the mesh opening adhered on the metal screen at a low filtration velocity, but the bounce-off of particles on the mesh surface suppressed the adhesion at a high velocity. As a result, we found that the adhesion of PSL particles larger than 0.3 μm mostly suppressed at a filtration velocity higher than 10 m s?1 and therefore we can sieve aerosol particles according to the opening size of metal screens. We also found that the particle number concentration could be determined by measuring the increase in pressure drop since the clogging of metal screen openings takes place by the individual particles.© 2016 American Association for Aerosol Research 相似文献