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Effect of Exit Geometry of Tail Pipe on the Performance of Pulse Jet Engines

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Journal of Thermal Science 2006年第3期15卷 263-268页

作者： Toshihiro nakano ShigeruMATSUO KenbuTERAMOTO ToshiakiSETOGUCHI Department of Mechanical Engineering Saga University1 Honjo-machiSaga-shiSaga 840-8502Japan

In this paper,the effect of geometries of tube open end on the shock,compression and expansion wavespropagating in the tube was investigated numerically and *** of them is a conventional straightshock tube with an open *** other has a divergent tail tube at the *** a divergent tail tube(flaretube)to an open end shock tube,the period of one-cycle process could be shortened and the pressure behind theexpansion wave produced at the exit of the shock tube could be lowered much more below the atmosphericpressure than that produced in the straight *** results suggested that the intake air into the engine wassignificantly increased by applying a flare tube instead of a straight tube.

关键词： compressible flow shock wave expansion wave pulse jet numerical simulation

Methane emissions from wetlands on the Qinghai-Tibet Plateau

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Chinese Science Bulletin 1999年第24期44卷 2282-2286页

作者： nakano Tomoko Department of Geography Tokyo Metropolitan University 192-03 Japan

The areal extent of cold freshwater wetlands on the Qinghai-Tibet Plateau (QTP) is estimated at 0.133 × 106 km2, suggesting a significant methane potential. Methane fluxes from wet alpine meadows, peatlands, Hippuris vulgaris mires and secondary marshes were 43.18, 12.96, -0.28 and 45.90 mgf33m-2f33d-1, respectively based on the transect flux studies at the Huashixia Permafrost Station (HPS) from July to August 1996. Average CH4 fluxes in the

关键词： QTP wetland ecosystems CH4 emission spatiality and seasonality fluxes.

Ideal Drift Response Curve for Robust Optimal Damper Design for Elastic-Plastic MDOF Structures under Multi-Level Earthquakes Dedicated to Professor Karl *** for his 95th birthday

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Computer Modeling in Engineering & Sciences 2021年第12期129卷 1181-1207页

作者： hiroki Akehashi Izuru Takewaki Department of Architecture and Architectural Engineering Graduate School of EngineeringKyoto UniversityKyotodaigaku-KatsuraNishikyoKyoto615-8540Japan

A new method of robust damper design is presented for elastic-plastic multi-degree-of-freedom(MDOF)building structures under multi-level ground motions(GMs).This method realizes a design that is effective for various levels of *** robustness of a design is measured by an incremental dynamic analysis(IDA)curve and an ideal drift response curve(IDRC).The IDRC is a plot of the optimized maximum deformation under a constraint on the total damper quantity *** design level of the *** total damper quantity corresponds to the total cost of the added ***,a problem of generation of IDRCs is ***,its solution algorithm,which consists of the sensitivity-based algorithm(SBA)and a local search method,is *** the application of the SBA,the passive added dampers are removed sequentially under the specified-level *** the other hand,the proposed local search method can search the optimal solutions for a constant total damper quantity under GMs’increased *** this way,combining these two algorithms enables the comprehensive search of the optimal solutions for various conditions of the status of the GMs and the total damper *** influence of selecting the type of added dampers(oil,hysteretic,and so on)and the selection of the input GMs on the IDRCs are ***,a robust optimal design problem is formulated,and a simple local search-based algorithm is proposed.A simple index using the IDRC and the IDA curve of the model is used as the objective *** is demonstrated that the proposed algorithm works well in spite of its simplicity.

关键词： Optimal damper placement robust damper design multi-level earthquake ideal drift response curve elastic-plastic MDOF model viscous damper hysteretic damper

A New Approach to Graph Recognition and Applications to Distance-Hereditary Graphs

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Journal of Computer Science & Technology 2009年第3期24卷 517-533页

作者： Shin-ichi nakano Ryuhei Uehara Takeaki Uno Department of Computer Science Faculty of EngineeringGunma UniversityGunma 376-8515Japan School of Information Science Japan Advanced Institute of Science and TechnologyIshikawa 923-1292Japan National Institute of Informatics Tokyo 101-8430Japan

Algorithms used in data mining and bioinformatics have to deal with huge amount of data efficiently. In many applications, the data are supposed to have explicit or implicit structures. To develop efficient algorithms for such data, we have to propose possible structure models and test if the models are feasible. Hence, it is important to make a compact model for structured data, and enumerate all instances efficiently. There are few graph classes besides trees that can be used for a model. In this paper, we investigate distance-hereditary graphs. This class of graphs consists of isometric graphs and hence contains trees and cographs. First, a canonical and compact tree representation of the class is proposed. The tree representation can be constructed in linear time by using prefix trees. Usually, prefix trees are used to maintain a set of strings. In our algorithm, the prefix trees are used to maintain the neighborhood of vertices, which is a new approach unlike the lexicographically breadth-first search used in other studies. Based on the canonical tree representation, efficient algorithms for the distance-hereditary graphs are proposed, including linear time algorithms for graph recognition and graph isomorphism and an efficient enumeration algorithm. An efficient coding for the tree representation is also presented; it requires [3.59n] bits for a distance-hereditary graph of n vertices and 3n bits for a cograph. The results of coding improve previously known upper bounds （both are 2^O（nlogn）） of the number of distance-hereditary graphs and cographs to 2^[3.59n] and 2^3n, respectively.

关键词： algorithmic graph theory cograph distance-hereditary graph prefix tree tree representation

CREB-binding proteins (CBP) as a transcriptional coactivator of GATA-2

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Science China(Life Sciences) 2008年第3期51卷 191-198页

作者： TOMOMI Takahashi TORU nakano Department of Pathology Medical School and Graduate School of Frontier Biosciences Osaka University Yamada-oka 2-2 Suita Osaka 565-0871 Japan

The GATA family consists of six members, GATA 1-6. In this study, we focused on GATA-2, which is expressed predominantly in hematopoietic progenitor cells and plays the key role in keeping these cells in the undifferentiated status. CREB-binding proteins (CBP) are essential transcriptional coacti- vators for a large number of regulated DNA-binding transcription factors, including GATA-1. But there have been no reports on whether CBP is still a co-activator of GATA-2. Here, we used the immunopre- cipitation and pull-down experiments to show that the GATA-2 and CBP were physically binding to- gether, and clarified the binding sites CH1, CH3 , CH452 and CT1430 in CBP and N-finger, C-finger and N-C-finger in GATA-2. Luciferase assay results in our experiment indicated that CBP could increase GATA-2 transcriptional activity in the dose-dependent manner. GATA-1 is mainly expressed in differen- tiated hematopoietic cells, but still has overlap expression with GATA-2. CBP is a coactivator of GATA-2 and GATA-1. The investigation on the mechanism that could decide whether CBP binds to GATA-2 to keep hematopoietic cells in the progenitor status or to GATA-1 to start differentiation will be a very in- teresting and very meaningful project in the near future.

关键词： CBP TATA-2 coactivator hematopoietic cells

Enhanced vibrational resonance in a single neuron with chemical autapse for signal detection

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Chinese Physics B 2020年第12期29卷 556-563页

作者： Zhiwei He Chenggui Yao Jianwei Shuai Tadashi nakano Department of Mathematics Shaoxing UniversityShaoxing 312000China College of Mathematics Physics and Information EngineeringJiaxing UniversityJiaxing 314000China Department of Physics State Key Laboratory of Cellular Stress BiologyInnovation Center for Cell Signaling NetworkXiamen UniversityXiamen 361102China Graduate School of Frontier Biosciences Osaka University5408570Japan

Many animals can detect the multi-frequency signals from their external *** understanding for underlying mechanism of signal detection can apply the theory of vibrational resonance,in which the moderate high frequency driving can maximize the nonlinear system's response to the low frequency subthreshold *** this work,we study the roles of chemical autapse on the vibrational resonance in a single neuron for signal *** reveal that the vibrational resonance is strengthened significantly by the inhibitory autapse in the neuron,while it is weakened typically by the excitatory *** is generally believed that the inhibitory synapse has a suppressive effect in neuronal ***,we find that the detection of the neuron to the low frequency subthreshold signal can be improved greatly by the inhibitory *** finding indicates that the inhibitory synapse may act constructively on the detection of weak signal in the brain and neuronal system.

关键词： neuronal dynamics autapse vibrational resonance synchronization time delay

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

A Wire-Driven Series Elastic Mechanism Based on Ultrasonic Motor for Walking Assistive System

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Chinese Journal of Mechanical Engineering 2023年第3期36卷 179-190页

作者： Weihao Ren hiroki Yoshioka Lin Yang Takeshi Morita State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and AstronauticsNanjing 210016China Graduate School of Frontier Sciences The University of TokyoKashiwa 2778563Japan

In order to improve the elderly people's quality of life,supporting their walking behaviors is a promising ***,based on one ultrasonic motor,a wire-driven series elastic mechanism for walking assistive system is proposed and investigated in this *** contrast to tradition,it innovatively utilizes an ultrasonic motor and a wire-driven series elastic mechanism to achieve superior system performances in aspects of simple structure,high torque/weight ratio,quiet operation,quick response,favorable electromagnetic compatibility,strong shock resistance,better safety,and accurately stable force *** proposed device is mainly composed of an ultrasonic motor,a linear spring,a steel wire,four pulleys and one rotating *** overcome the ultrasonic motor's insufficient output torque,a steel wire and pulleys are smartly combined to directly magnify the torque instead of using a conventional gear *** the pulleys,there is one tailored pulley playing an important role to keep the reduction ratio as 4.5 ***,the prototype is manufactured and its actual performance is verified by experimental *** a one-second operating cycle,it only takes 86 ms for this mechanism to output an assistive torque of 1.6 N·*** this torque,the ultrasonic motor's speed is around 4.1 rad/***,experiments with different operation periods have been conducted for different application *** study provides a useful idea for the application of ultrasonic motor in walking assistance system.

关键词： Ultrasonic motor Wire-driven Series elastic mechanism Walking assistive system Pulley Reduction ratio

Linear Stability Analysis on the Influences of the Spatial Variations in Thermal Conductivity and Expansivity on the Flow Patterns of Thermal Convection with Strongly Temperature-Dependent Viscosity

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Journal of Earth Science 2014年第1期25卷 126-139页

作者： Arata Miyauchi Masanori Kameyama hiroki Ichikawa Geodynamics Research Center Ehime University

A series of linear stability analysis is carried out on the onset of thermal convection in the presence of spatial variations of viscosity, thermal conductivity and expansivity. We consider the temporal evolution of an infinitesimal perturbation superimposed to a static （motionless） and con- ductive state in a basally-heated planar layer. From the changes in flow patterns with increasing the amplitudes of temperature dependence of viscosity, we identified the transition into the ＂stagnant-lid＂（ST） regime, where the convection occurs only beneath a thick and stagnant-lid of cold fluid at the top surface. Detailed analysis showed a significant increase of the aspect ratio of convection cells in ST regime induced by the spatial variations in thermal conductivity and/or expansivity： the horizon- tal length scale of ST convection can be enlarged by up to 50% with 10 times increase of thermal conductivity with depth. We further developed an analytical model of ST convection which success- fully reproduced the mechanism of increasing horizontal length scale of ST regime convection cells for given spatial variations in physical properties. Our findings may highlight the essential roles of the spatial variation of thermal conductivity on the convection patterns in the mantle.

关键词： mantle convection stagnant-lid temperature-dependent viscosity pressure- dependent thermal conductivity pressure-dependent thermal expansivity linear stability analysis.