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991.
Takatoshi Shindo Hideki Motoyama Akira Sakai Noriyasu Honma Jun Takami Masahito Shimizu Kiyoshi Tamura Kazuo Shinjo Fumio Ishikawa Yoshiyuki Ueno Masateru Ikuta Daisuke Takahashi 《IEEJ Transactions on Electrical and Electronic Engineering》2012,7(3):251-257
We summarize the lightning data for 17 years from 1992 to 2008 obtained with lightning location systems of nine electric power utilities in Japan and analyze them. The observed annual number of lightning flashes of which the current is more than 10 kA is 400 000–800 000 and the 50% value of the cumulative distribution of lightning peak currents is about 23 kA in recent times. The variation of lightning occurrence characteristics by areas, seasons, and so on, is clarified. Comparison of the obtained data with those obtained by another lightning location system is also made. The relationship between lightning occurrence and climate is discussed. © 2012 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
992.
对于“直流电机+滚珠丝杠”驱动机构,摩擦是实现大行程具有纳米级分辨率点位控制的主要障碍.通过设计高增益PID控制器,可以抑制摩擦的影响并在大范围内实现纳米定位,只是系统的性能受到执行机构饱和的影响.通过将时间优化的Bang—Bang控制器与该PID控制器结合在一起构成变结构控制系统,使用PID闭环控制跟踪Bang—Bang控制下的理论减速轨迹,并实现最终定位,从而消除了饱和所造成的超调.实验和仿真结果显示,该系统可以在较大摩擦力和模型参数变化的情况下获得大范围无超调的纳米定住,并且响应时间最优. 相似文献
993.
Junko Oi Akira Obuchi Gratian R. Bamwenda Atsushi Ogata Hiroshi Yagita Satoshi Kushiyama Koichi Mizuno 《Applied catalysis. B, Environmental》1997,12(4):483-286
The catalytic decomposition of nitrous oxide to nitrogen and oxygen was studied overRh/ZnO, Rh/CeO2, Rh/ZSM-5, CuZSM-5 and CoAlCO3HT (hydrotalcite). The effects of metal loading and calcination conditions upon the catalytic performance were examined on Rh/ZnO. A 0.5 wt.% Rh/ZnO catalyst was found to be the most active catalyst, whose reaction rate was 4.0 × 104 μmol(N2O) · g−1 · h−1 under the conditions of 950 ppm N2O and 5% O2 at 300°C. The oxidized Rh/ZnO showed a higher activity than that calcined in a reducing atmosphere. The TEM and EDX observations revealed the formation of particles of ca. 50Åin diameter. They consisted of rhodium and zinc oxides as major and minor components, respectively. The activities of all these catalysts decreased when NO2 and H2O were added to the feed. 相似文献
994.
Akira Takami 《Powder Technology》1976,14(1):1-6
A mathematical analysis of the distribution of pressure (vertical stress) in powder mass filled in a conical vessel is presented, taking into account the variation of pressure with the distance from the axis of the cone. The free surface of the powder mass is assumed to be heaped. It is assumed that vertical stress and horizontal stress are interrelated by Rankine's law. From the equilibrium condition of powder mass a fundamental equation has been derived to determine the pressure as a function of both the depth and the distance from the axis of the cone. A solution satisfying the boundary condition at the free surface has been obtained. It is shown that the analysis fits the experimental curves of the distribution of vertical stress 相似文献
995.
Sakai M Hashimoto A Yoshida N Suzuki S Kameshima Y Nakajima A 《The Review of scientific instruments》2007,78(4):045103
An analysis system was developed to evaluate the sliding behavior of a liquid droplet on a hydrophobic surface. This system enables continuous and simultaneous measurement of both the sliding acceleration and shape deformation during the sliding of a liquid droplet. Moreover, the velocity vector of the internal fluidity of a sliding droplet was obtained by employing particle image velocimetry in the analysis system. This evaluation method pioneers the measurement of the dynamic wettability of a hydrophobic solid surface. 相似文献
996.
Yuusuke Tanaka Akira Tanabe Katsumi Suzuki Tsutomu Miyatake Masaki Hirose 《Journal of Electronic Materials》1998,27(8):936-940
The effects of synchrotron x-ray irradiation on the device characteristics and hot-carrier resistance of n- and p-channel
metal oxide semiconductor field effect transistors (MOSFETs) with 4 nm thick gate oxides are investigated. In p-channel MOSFETs,
device characteristics were significantly affected by the x-ray irradiation but completely recovered after annealing, while
the device characteristics in n-channel MOSFETs were not noticeably affected by the irradiation. This difference appears to
be due to a difference in interface-state generation. In p-channel MOSFETs, defects caused by boron-ion penetration through
the gate oxides may be sensitive to x-ray irradiation, causing the generation of many interface states. These interface states
are completely eliminated after annealing in hydrogen gas. The effects of irradiation on the resistance to hot-carrier degradation
in annealed 4 nm thick gate-oxide MOSFETs were negligible even at an x-ray dose of 6000 mJ/cm2. 相似文献
997.
J Nie S Sakamoto D Song Z Qu K Ota T Taniguchi 《Canadian Metallurgical Quarterly》1998,424(1-2):27-32
Ataxia telangiectasia (AT) cells display a profound sensitivity to ionizing radiation, exhibiting more frequent chromosomal breaks, increased micronuclei formation and abnormal DNA repair kinetics following exposure. Despite the recent cloning of the ATM gene there remains a need for a simple and rapid means of discriminating AT heterozygotes from normal individuals. Caffeine (1,3,7-trimethyl xanthine), known to inhibit the repair of double-strand DNA breaks following ionizing radiation, increases the frequency of radiation induced chromosomal breaks in normal cells. Here we report that caffeine potentiates the induction of chromosomal breaks in G2 arrested AT heterozygote and normal lymphoblastoid cells, but not in homozygous AT lymphoblastoid cells. This observation parallels the findings reported by others that caffeine fails to potentiate the effect of ionizing radiation in radiation-sensitive yeast strains and radiation sensitive CHO cells. It also suggests that caffeine may somehow mimic the effect of the ATM gene product in normal cells. We also report that caffeine is unlikely to be useful in helping to discriminate AT heterozygotes from normal individuals. 相似文献
998.
An optical-heterodyne-detection method for a 60-GHz radio-on-fiber uplink is proposed and verified in this paper. The main point of this proposal is that all the functions needed for the optical heterodyne detection, i.e., the local/carrier light sources, the automatic frequency control of these light sources, and a polarization-diversity-detection circuit, are consolidated in one transmitting-side module to realize a simple system configuration. This proposal realizes an adequate optical uplink budget with low-cost optical receivers that consist of just one IF-band photodetector and one envelope detector. A 1.0-Gb/s transmission experiment over 10 km of single-mode fiber, which represents access-network transmission, is demonstrated using a 61.0-GHz amplitude-shift-keying signal as a 60 GHz-band uplink signal. A BER of less than 10-9 was obtained at an uplink SSB signal power of -40 dBm regardless of the polarization state of the optical uplink signal, and no significant dispersion-induced degradation was noted. 相似文献
999.
This paper proposes deep and fundamental structures of communication among persons in a “coexistential” setting. The basic
framework for this formalization of communication structures is Leibnizian notions of space and time together with the notion
of the Existential Graph by C. S. Peirce and that of the Petri net, more precisely, the occurrence net. The fundamental structures
of coexistential communication are then formalized as co-creation of Leibnizian space and time in such a manner that they
are used to link the communicated messages, thus establishing the “coexistential atmosphere and field” (“Ba” in Japanese)
among the individuals. This framework is then applied to the analysis of theater play communication. Finally, the framework
of information edaphology is also introduced to discuss the growth processes of individuals and communities through coexistential
communication. 相似文献
1000.
Kazuichi Hayakawa Yu Onoda Chihiro Tachikawa Morio Yoshita Akira Toriba Takayuki Kameda 《Polycyclic Aromatic Compounds》2013,33(4-5):382-391
Binding activities and estrogenic/antiestrogenic activities of polycyclic aromatic hydrocarbons (PAHs) and hydroxylated PAHs (OHPAHs) having 2 to 6 rings were evaluated by competition assay and yeast two-hybrid assay expressing human estrogen receptor (hER), respectively. PAHs did not bind to hER and did not show any activity. On the other hand, OHPAHs bound to hER and several OHPAHs showed estrogenic or antiestrogenic activity. Relative estrogenic activity (REP E ) and antiestrogenic activity (REP AE ) were calculated from the values of E 2 and 4-hydroxytamoxyfen as positive controls, respectively. Several OHPAHs having 4 rings showed strongly estrogenic activity. 4-Hydroxybenzo[a]anthracene exhibited the strongest estrogenic activity (REP E = 7.5 × 10?3 ) followed by 3-hydroxybenzo[a]anthracene and 2-hydroxychrysene (REP E = 4.2 × 10?3 ). Several other 4-ring OHPAHs showed strongly antiestrogenic activity. 3-Hydroxybenzo[c]phenanthrene exhibited the strongest antiestrogenic activity (REP AE = 190) followed by 2-hydroxybenzo[c]phenanthrene (REP AE = 69) and 2- hydroxybenz [a]anthracene (REP AE = 0.42). The results suggested that there is a strong structure – activity relationship. 相似文献