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Effects of uniaxial compressive strain on the electronic- transport properties of zigzag carbon nanotubes

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Nano Research 2016年第5期9卷 1267-1275页

作者： Masato Ohnishi Ken Suzuki Hideo miura Fracture and Reliability Research Institute Graduate School of Engineering Tohoku University Sendai 980-8579 Japan

Recently, substantial attention has been paid to the strain sensitivity of the carbon nanotubes＇（CNTs＇） electronic properties. In this study, the relationships between the geometric structures and electronic states of zigzag CNTs under uniaxial compressive strain were investigated. We found that different factors dominate the electronic states of zigzag CNTs depending on the strain regions： the initial stage of the strain loading, which lasts until column-buckling deformation begins, and the strain regions corresponding to column- and shell-buckling deformations. Because shell-buckling deformation significantly increases the re-orbital angle, the angle between the π orbital axis vectors of adjacent atoms, strong localization of the density of states （LDOS） occurs in the buckled area. We also analyzed the current able to pass through deformed CNTs using a tight-binding-based Green＇s function approach and determined that the current can be significantly suppressed by applying uniaxial compressive strain. Our method of predicting the electronic state of a deformed CNT based on the π-orbital angle is expected to be useful for predicting the electronic properties of CNT-based electronic devices and sensors.

关键词： carbon nanotube strain buckling deformation Green's function method electronic-transport property

Experimental Investigation of Stator Flow in Diagonal Flow Fan

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Journal of Thermal Science 2008年第4期17卷 356-360页

作者： Jie Wang Yoichi Kinoue norimasa Shiomi Toshiaki Setoguchi Kenji Kaneko Yingzi Jin Zhejiang Sci-Tech University Xiasha Higher Educatinal Zone Hangzhou 310018 China Department of Mechanical Engineering Saga University 1 Honjo Saga 840-8502 Japan

Experimental investigations were conducted for the internal flow of the stator of the diagonal flow fan. Comer separation near the hub surface and the suction surface of the stator blade are focused on. At the design flow rate, the values of the axial velocity and the total pressure at stator outlet decrease near the suction surface at around the hub surface by the influence of the comer wall. At low flow rate of 80-90 % of the design flow rate, the comer separation between the suction surface and the hub surface can be found, which become widely spread at 80 % of the design flow rate.

关键词： diagonal flow rotor axial flow stator internal flow corner separation

Last deglacial relative sea level variations in Antarctica derived from glacial isostatic adjustment modelling

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Geoscience Frontiers 2013年第6期4卷 623-632页

作者： Jun’ichi Okuno Hideki miura National Institute of Polar Research 10-3 Midori-choTachikawaTokyo 190-8518Japan Research Institute for Global Change Japan Agency for Marine-Earth Science and Technology3173-25 Showa-machiKanazawa-kuYokohama 236-0001Japan

We present relative sea level （RSL） curves in Antarctica derived from glacial isostatic adjustment （GIA）predictions based on the melting scenarios of the Antarctic ice sheet since the Last Glacial Maximum （LGM）given in previous ***,Holocene-age RSL observations obtained at the raised beaches along the coast of Antarctica are shown to be in agreement with the GIA *** differences from previously published ice-loading models regarding the spatial distribution and total mass change of the melted ice are *** models were also derived from GIA modelling; the variations can be attributed to the lack of geological and geographical evidence regarding the history of crustal movement due to ice sheet ***,we summarise the previously published ice load models and demonstrate the RSL curves based on combinations of different ice and earth *** RSL curves calculated by GIA models indicate that the model dependence of both the ice and earth models is significantly large at several sites where RSL observations were *** particular,GIA predictions based on the thin lithospheric thickness show the spatial distributions that are dependent on the melted ice thickness at each *** characteristics result from the short-wavelength deformation of the ***,our predictions strongly suggest that it is possible to find the average ice model despite the use of the different models of lithospheric *** sea level and crustal movement observations,we can deduce the geometry of the post-LGM ice sheets in detail and remove the GIA contribution from the crustal deformation and gravity change observed by space geodetic techniques,such as GPS and GRACE,for the estimation of the Antarctic ice mass change associated with recent global warming.

关键词： Antarctic ice sheet Relative sea level Glacial isostatic adjustment Melting history Lithospheric thickness

Analysis and control of vibration of ropes in a high-rise elevator under earthquake excitation

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Earthquake Engineering and Engineering Vibration 2019年第2期18卷 447-460页

作者： Thuan Xuan Nguyen Nanako miura Akira Sone Faculty of Mechanical Engineering Kyoto Institute Technology Matsugasaki

In this research, the vibration of elevator ropes, including the main rope and compensation rope are investigated simultaneously in a high-rise elevator system under earthquake excitation. Moreover, the paper presents a new control method to restrain the sway of both ropes. This study considers varying rope lengths during elevator operation which cause other system parameters such as natural frequency, and damping ratio to be time-variant variables. The dynamics of the ropes are analyzed by solving the governing non-stationary, nonlinear equation numerically. In order to mitigate the vibration of ropes in several motion conditions, particularly upwards movement, downward movement, stopped at the lowest position, and stopped at the highest position, an active equipment is installed at the compensation sheave. The stability of the system using the controller is analyzed at four states: without disturbance and static car, without disturbance and mobile car, including disturbance and static car, and including disturbance and mobile car. The efficiency of the controller used for dampening the vibration of elevator ropes is validated by numerical simulation results.

关键词： elevator ropes high-rise elevator vibration controller stability

Quantitative classification of Camellia japonica and Camellia rusticana(Theaceae)based on leaf and flower morphology

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Plant Diversity 2021年第3期43卷 216-224页

作者： Harue Abe Hiroki miura Yoshitaka Motonaga Center for Sustainable Agriculture and Forestry Faculty of AgricultureNiigata University94-2 KodaSadoNiigata952-2206Japan Aomori Prefectural Asamushi Aquarium 1-25 BabayamaAsamushiAomoriAomori039-3501Japan Faculty of Agriculture Niigata University8050 Ikarashi-ninochoNishi-kuNiigata950-2181Japan

In Japan,Camellia japonica and Camellia rusticana are naturally *** differences in their habitats and morphologies,they have been classified by various researchers as either varieties,subspecies,or *** taxonomic position of *** and *** remain unclear because morphological comparisons have been restricted to limited areas and quantitative data are *** grows in snowy places,unlike *** *** displays ornithophily,*** displays *** species have adapted to different growing environments and pollinators,which have altered the morphology of flowers and *** therefore quantitatively estimated the differentiation between these two taxa by comparing the morphologies of leaf hypodermis,flower form,petal color,and filament color in twenty *** findings allowed us to differentiate these two species by the presence or absence of a leaf *** also discovered an intermediate type of leaf hypodermis,which might also be caused by *** component analysis(PCA)indicated that the flower morphologies between these species were significantly *** petal and filament colors were also significantly *** quantitative analysis suggests that speciation caused by differences in both pollinators and environment is one of the factors involved in this *** findings in *** and *** help to explain speciation processes for other species as well.

关键词： Camellia japonica Camellia rusticana Ecological isolation Pollinator shift Pollination syndrome Reproductive isolation

Combined disturbance-observer-based control and iterative learning control design for pulsed superconducting radio frequency cavities

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Nuclear Science and Techniques 2021年第6期32卷 11-22页

作者： Feng Qiu Shinichiro Michizono Toshihiro Matsumoto Takako miura High Energy Accelerator Research Organization 1-1 OhoTsukubaIbaraki 305-0801Japan The Graduate University for Advanced Studies HayamaKanagawa 240-0193Japan Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China

The development of iterative learning control combined with disturbance-observer-based(DOB)control for the digital low-level radio frequency(LLRF)system of the International Linear Collider project is *** objective of this study is to compensate for both repetitive(or predictable)and unpredictable disturbances in a radio frequency system(e.g.,beam loading,Lorentz force detuning,and microphonics).The DOB control approach was verified using the LLRF system at the Superconducting Test Facility(STF)at KEK in the absence of a *** method comprising DOB control combined with an iterative learning control algorithm was then demonstrated in a cavity-simulator-based test bench,where a simulated beam was *** results showed that the performance of the LLRF system was improved,as expected by this combined control *** plan to further generalize this approach to LLRF systems at the STF and the future International Linear Collider project.

关键词： Low-level radio frequency Disturbance observer Iterative learning control

Application of Brillouin Optical Correlation Domain Analysis for Crack Identification in Concrete Structure

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Photonic Sensors 2013年第4期3卷 377-384页

作者： Michio IMAI Satoru miura Kajima Technical Research Institute Tokyo 1820036 Japan

This paper investigates the application of distributed optical fiber strain sensors to civil engineering structures, because no other tool can satisfactorily detect the location of the unpredictable phenomenon. In fact, the locations of cracks in the concrete structure are unknown a priori; therefore, a fully distributed sensor is necessary to detect them. The Brillouin optical correlation domain analysis （BOCDA）, which offers high spatial resolution by using stimulated Brillouin scattering along the whole length of the optical fiber, is used in a wide range of civil engineering applications, and the same has undergone significant development over the last decade. In this paper, it is demonstrated how a BOCDA-based strain sensor can be employed to monitor cracks in concrete. Crack monitoring on the surface of the concrete member provides useful information for evaluating stiffness and durability of the structure, particularly for early detection of tiny cracks, which is essential for preventing crack growth and dispersion. The crack-induced strain distribution was analytically investigated, and it was proved that BOCDA can identify even a small crack before its visual recognition by a beam test. Moreover, periodical crack monitoring was successfully executed on a pedestrian deck for five years.

关键词： Stimulated Brillouin scattering optical fiber sensor strain measurement distributed sensing

Effects of Aspect Ratio in a Transonic Shock Tube Airfoil Flow

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Journal of Thermal Science 2012年第5期21卷 435-440页

作者： Masashi KASHITANI Keita miura Shinichiro NAKAO Yutaka YAMAGUCHI Department of Aerospace Engineering National Defense Academy1-10-20 Hashirimizu Yokosuka 239-8686 JAPAN Department of Mechanical Engineering Nagasaki Institute of Applied Science 536 Aba-MachiNagasaki 851-0193 JAPAN

In the present study, the flow visualizations were performed around the NACA 0012 models which differ in aspect ratios. We discussed the effects of the aspect ratio in the test models. Additionally the unsteady, two-dimensional, compressible Euler equations were solved for the NACA 0012 airfoil. Experiments were performed utilizing the conventional gas driven shock tube as the intermittent transonic wind tunnel. The aspect ratios of the models are about 0.86 and 1.5, respectively. The Mach numbers M 2 are about 0.84. The Reynolds numbers of the present experimental conditions were constant that Re based on chord length is about 4.0×10 5 . The results are as follows: in different aspect ratios, the difference of the shock wave location is confirmed though the Mach number and Reynolds number are same. It indicates the different correction Mach number by the effects of the side wall boundary layer though the nominal Mach number measured the same value. Also, on the difference of shock wave location for the effects of the aspect ratio, the tend of CFD shows the qualitative agreement with the result of an experiment.

关键词： Shock tube Aerodynamics Transonic flows Aspect ratio Wind tunnel correction

Role of gut microbiota and Toll-like receptors in nonalcoholic fatty liver disease

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World Journal of Gastroenterology 2014年第23期20卷 7381-7391页

作者： Kouichi miura Hirohide Ohnishi Department of Gastroenterology Akita University Graduate School of MedicineAkita 010-8543Japan

Emerging data have shown a close association between compositional changes in gut microbiota and the development of nonalcoholic fatty liver disease(NAFLD).The change in gut microbiota may alter nutritional absorption and *** addition,gut microbiota are a source of Toll-like receptor(TLR)ligands,and their compositional change can also increase the amount of TLR ligands delivered to the *** ligands can stimulate liver cells to produce proinflammatory ***,the gut-liver axis has attracted much interest,particularly regarding the pathogenesis of *** abundance of the major gut microbiota,including Firmicutes and Bacteroidetes,has been considered a potential underlying mechanism of obesity and NAFLD,but the role of these microbiota in NAFLD remains *** reports have demonstrated that certain gut microbiota are associated with the development of obesity and *** instance,a decrease in Akkermansia muciniphila causes a thinner intestinal mucus layer and promotes gut permeability,which allows the leakage of bacterial *** to increase Akkermansia muciniphila improve the metabolic parameters in obesity and *** children,the levels of Escherichia were significantly increased in nonalcoholic steatohepatitis(NASH)compared with those in obese *** can produce ethanol,which promotes gut ***,normalization of gut microbiota using probiotics or prebiotics is a promising treatment option for *** addition,TLR signaling in the liver is activated,and its downstream molecules,such as proinflammatory cytokines,are increased in *** data,TLR2,TLR4,TLR5,and TLR9 have been shown to be associated with the pathogenesis of ***,gut microbiota and TLRs are targets for NAFLD treatment.

关键词： Nonalcoholic fatty liver disease Nonalcoholic steatohepatitis Gut microbiota Toll-like receptor Probiotics Prebiotics