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Manipulation of Micro Solid Particles and Induced Flows in Water by Laser Irradiation

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Journal of Thermal Science 2007年第2期16卷 176-180页

作者： masahiro OTA Hiroshi OKANO Makoto YOSHIDA Division of Mechanical Engineering Tokyo Metropolitan University1Minami-osawaHachi-ojiTokyo 192-0397Japan

Q-switch for pulsing laser beam and Galvano scanner for rapid scanning laser beam were adapted to manipulate micro solid particles in a water droplet. The trapping of fine particles at micron-sized diameters by a YAG laser system, induced flows, and the induced motion of the particles by laser beam irradiations are discussed. Particle rotations are observed by using anisotropic micro objects, and moreover the rotational rate with clockwise direction is 22 r/min. The fragments of a cover glass were mixed in a water droplet, and their size and shape are uneven. The rotation of that non-spheres without scanning by the Galvano scanner is also observed in water.

关键词： Laser trapping non-sphere particle optical radiation pressure laser scanning laser drive rotation

Analysis of molten metal spreading and solidification behaviors utilizing moving particle full-implicit method

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Frontiers in Energy 2021年第4期15卷 959-973页

作者： Ryo YOKOYAMA masahiro KONDO Shunichi SUZUKI Koji OKAMOTO Department of Nuclear Engineering and Management The University of Tokyo7-3-1 HongoBunkyo-kuTokyo 113-8656Japan Research Center for Computational Design of Advanced Functional materials(CD-FMat) Department of Materials and ChemistryNational Institute of Advanced Industrial Science and Technology(AIST)Central 21-1-1UmezonoTsukubaIbaraki 305-8568Japan Institute of Engineering Innovation School of EngineeringThe University of Tokyo7-3-1 HongoBunkyo-kuTokyo 113-8656Japan Nuclear Professional School The University of Tokyo2-22 ShirakataTokai-muraIbaraki 319-1188Japan

To retrieve the fuel debris in Fukushima Daiichi Nuclear Power Plants(1F),it is essential to infer the fuel debris *** particular,the molten metal spreading behavior is one of the vital phenomena in nuclear severe accidents because it determines the initial condition for further accident scenarios such as molten core concrete interaction(MCCI).In this study,the fundamental molten metal spreading experiments were performed with different outlet diameters and sample amounts to investigate the effect of the outlet for spreading-solidification *** the numerical analysis,the moving particle full-implicit method(MPFI),which is one of the particle methods,was applied to simulate the spreading *** the MPFI framework,the melting-solidification model including heat transfer,radiation heat loss,phase change,and solid fraction-dependent viscosity was developed and *** addition,the difference in the spreading and solidification behavior due to the outlet diameters was reproduced in the *** simulation results reveal the detailed solidification procedure during the molten metal *** is found that the viscosity change and the solid fraction change during the spreading are key factors for the free surface condition and solidified ***,it is suggested that the MPFI method has the potential to simulate the actual nuclear melt-down phenomena in the future.

关键词： molten metal spreading solidification particle method severe accident fuel debris decommissioning

The structural elucidation of Eisenstein's formula

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Science China Mathematics 2010年第9期53卷 2341-2350页

作者： HASHIMOTO masahiro KANEMITSU Shigeru Department of Mathematics Wakayama College of TechnologyNoda-machi Gobo-shi 649-15Japan Graduate School of Advanced Technology Kinki University IizukaFukuoka 820-8555Japan

In this paper,we shall give a complete structural description of generalizations of the classical Eisenstein formula that expresses the first periodic Bernoulli polynomial as a finite combination of cotangent values,as a relation between two bases of the vector space of periodic Dirichlet *** shall also determine the limiting behavior of them,giving rise to Gauss' famous closed formula for the values of the digamma function at rational points on the one hand and elucidation of Eisenstein-Wang's formulas in the context of Kubert functions on the other.W shall reveal that most of the relevant previous results are the combinations of the generalized Eisenstein formula and the functional equation.

关键词： Eisenstein formula Hurwitz zeta-function polylogarithm function Gauss formula

Two-Dimensional Parabolic Inverse Source Problem with Final Overdetermination in Reproducing Kernel Space

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Chinese Annals of Mathematics,Series B 2014年第3期35卷 469-482页

作者： Wenyan WANG masahiro YAMAMOTO Bo HAN Department of Mathematics Harbin Institute of Technology Department ofMathematics Northeast Forestry University Graduate School of Mathematical Sciences The University of Tokyo

A new method of the reproducing kernel Hilbert space is applied to a twodimensional parabolic inverse source problem with the final overdetermination. The exact and approximate solutions are both obtained in a reproducing kernel space. The approximate solution and its partial derivatives are proved to converge to the exact solution and its partial derivatives, respectively. A technique is proposed to improve some existing methods. Numerical results show that the method is of high precision, and confirm the robustness of our method for reconstructing source parameter.

关键词： Inverse source problem Final overdetermination Parabolic equation Reproducing kernel

Angiogenesis and neuronal remodeling after ischemic stroke

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Neural Regeneration Research 2020年第1期15卷 16-19页

作者： masahiro Hatakeyama Itaru Ninomiya Masato Kanazawa Department of Neurology Brain Research Institute Niigata University

Increased microvessel density in the peri-infarct region has been reported and has been correlated with longer survival times in ischemic stroke patients and has improved outcomes in ischemic animal *** raises the possibility that enhancement of angiogenesis is one of the strategies to facilitate functional recovery after ischemic *** vessels and neuronal cells communicate with each other using various mediators and contribute to the pathophysiology of cerebral ischemia as a *** this mini-review,we discuss how angiogenesis might couple with axonal outgrowth/neurogenesis and work for functional recovery after cerebral *** occurs within 4 to 7 days after cerebral ischemia in the border of the ischemic core and ***-ischemic angiogenesis may contribute to neuronal remodeling in at least two ways and is thought to contribute to functional ***,new blood vessels that are formed after ischemia are thought to have a role in the guidance of sprouting axons by vascular endothelial growth factor and laminin/β1-integrin ***,blood vessels are thought to enhance neurogenesis in three stages:1)Blood vessels enhance proliferation of neural stem/progenitor cells by expression of several extracellular signals,2)microvessels support the migration of neural stem/progenitor cells toward the peri-infarct region by supplying oxygen,nutrients,and soluble factors as well as serving as a scaffold for migration,and 3)oxygenation induced by angiogenesis in the ischemic core is thought to facilitate the differentiation of migrated neural stem/progenitor cells into mature ***,the regions of angiogenesis and surrounding tissue may be coupled,representing novel treatment targets.

关键词： angiogenesis axonal outgrowth cerebral ischemia coupling functional recovery guidance neurogenesis stroke

Unstable Head-Flow Characteristic Generation Mechanism of a Low Specific Speed Mixed Flow Pump

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Journal of Thermal Science 2006年第2期15卷 115-120,144页

作者： masahiro MIYABE Hideaki MAEDA Isamu UMEKI Yoshinori JITTANI Department R & D Torishima Pump Mfg. Co. Ltd. 1-1-8 Miyata-cho Takatsuki-shi Osaka 569-8660 JAPAN

This paper treats the flow instabilities in a mixed flow pump with a vaned diffuser. Test pump has a positive slope of a head-flow performance curve at 65% flow rate of BEP (Best Efficiency Point) because of a rotating stall. Dynamic Particle Image Velocimetry (PIV) and pressure fluctuation measurements are used for investigating the propagation mechanism of a rotating stall. It was found that unstable performance was caused by periodical large scale abrupt backflow generated from the vaned diffuser to the outlet of impeller. Further, the relation between the static pressure at the inlet of diffuser vane and the internal flow condition was clarified. From these experimental results, in order to improve the positive slope of a head-flow performance curve, to suppress the growth of strong vortex toward the inlet of diffuser vane was proved to be a key point.

关键词： mixed flow pump vaned diffuser flow instabilities rotating stall dynamic PIV

Earthquake engineering research needs in light of lessons learned from the 2011 Tohoku earthquake

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Earthquake Engineering and Engineering Vibration 2014年第S1期13卷 141-149页

作者： Masayoshi Nakashima Oren Lavan masahiro Kurata Yunbiao Luo Disaster Prevention Research Institute (DPRI) Kyoto University Professor Disaster Prevention Research Institute (DPRI) Kyoto UniversityGokashoUjiKyotoJapan Faculty of Civil and Environmental Engineering Technion–Israel Institute of TechnologyHaifaIsrael Assistant Professor Post Doctoral Fellow

Earthquake engineering research and development have received much attention since the first half of the twentieth century. This valuable research presented a huge step forward in understanding earthquake hazard mitigation,which resulted in appreciable reduction of the effects of past earthquakes. Nevertheless,the 2011 Tohoku earthquake and the subsequent tsunami resulted in major damage. This paper presents the timeline of earthquake mitigation and recovery,as seen by the authors. Possible research directions where the authors think that many open questions still remain are identified. These are primarily based on the important lessons learned from the 2011 Tohoku earthquake.

关键词： research needs earthquake engineering quick recovery 2011 Tohoku earthquake

Analysis on IPv4 Address's Running Out Day in China

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光学学报 2003年第S1期23卷 749-750页

作者： masahiro OJIMA HITACHI China R&D Ubiquitous IT dep. Beijing China

IPv6 related research is widely developed. It is important to China also. So this report describes current IPv4 address allocation status of China. Then it analyzes address usage. After describing the factors above, this report makes several assumptions and gets the result of IPv4 address's running out day in China. Conclusion is in 2006 IPv4 address in China will run out and IPv6 related applications are to be on the stage.

关键词： in IP on Analysis on IPv4 Address’s Running Out Day in China have ASN that of from line

Stereoselective Total Synthesis of Mycalamides

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复旦学报（自然科学版） 2005年第5期44卷 813-814页

作者： masahiro Toyota Department of Chemistry Graduate School of Science Osaka Prefecture University Sakai Osaka 599-8531 Japan

Mycalamides A (1a) and B (1b) are potent antiviral compounds from a New Zealand sponge of the genus Mycale. Apart from their antitumor property, mycalamide A (1a) exhibits immunosuppressive action by blocking T-cell activation in mice and is significantly more potent than FK-506 and cyclosporine A. Because of their intriguing biological activity, unique structures and scarce supply of these natural products, mycalamides A (1a) and B (1b) have attracted considerable attention as target molecules for total synthesis, and total, formal, or partial syntheses of this family of compounds have been reported[1,2].

关键词：立体选择性微生物抗滤过性病原体抗癌抗菌素免役抑制