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Finite-element implementation of reverse-time migration for anisotropic media

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Finite-element implementation of reverse-time migration for ...

中国科学院地质与地球物理研究所2004学术年会

作者： Meigen Zhang,Xiaofan Li and Miaoyue Wang Institute of Geology and Geophysics,chinese Academy of sciences,beijing 100029 china

Reverse-time migration for post-stack seismic data in anisotropic media is implemented using the finite-element *** an accurate digital method,the finite-element method is flexible for dealing with complicated geological structures,inner and man-made boundaries despite its intensive *** it in reverse-time migration may produce accurate images for anisotropic *** eliminate man-made boundary reflections,the absorbing boundary condition for anisotropic elastic waves is also *** efficient and stable absorbing boundary scheme is presented combining a discrete transparent boundary condition with an attenuation boundary condition.

关键词： finite-element method reverse-time migration absorbing boundary condition

Study on the Ultrastructures of Antennal Sensilla in Helicoverpa armigera

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Agricultural sciences in china 2002年第8期1卷 896-899页

作者： WANG Gui-rong, GUO Yu-yuan and WU Kong-ming( State Key Laboratory of Plant Disease and Insect Pests, The Institute of Plant Protection , chinese Academy of Agricultural sciences, beijing 100094 , P. R . china ) State Key Laboratory of Plant Disease and Insect Pests The Institute of Plant Protection Chinese Academy of Agricultural Sciences Beijing 100094 P. R . China

The morphology and structures of antennal sensilla of Helicoverpa armigera are observed under scanning and transmission electron microscopes. Antennae of Helicoverpa armigera are made up of scapus, pedicel and flagellum that the latter consists of 70 - 82 segments. The inner side surface of antenna is cat-aphracted and most of the antennal sensilla lie on its outer, upper and lower surfaces. Both the antennae of male and female contain five kinds of antennal sensilla, namely, sensillum trichodeum, sensillum basicon-icum, sensillum chaeticum, ear-shaped sensillum and sensillum coeloconicum, and the kinds, number and distribution of antennal sensilla of both sexes are similar. There are a large number of serrate cuticular processes on antennal surface, especially on the middle and basic parts of antenna. Sensillum trichodeum and sensillum basiconicum, the main chemical odor receptors on antennae of Helicoverpa armigera, consist of cuticular-wall, sheath cells, lymph and dendrites. There are significant differences between the internal structures of the two kinds of sensilla. In sensillum trichodeum, the cuticular-wall is thicker, less lipophilic pore channels and has one or a few dendrites, while in sensillum basiconicum, the cuticular-wall is thinner, abundant lipophilic pore channels and has much more dendrites.

关键词： Helicoverpa armigera Antennal sensillum Ultrastructures Scanning electron microscope Transmission electron microscope

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Cratonization and the Ancient North china Continent:A summary and review

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Cratonization and the Ancient North China Continent:A summar...

中国科学院地质与地球物理研究所第11届（2011年度）学术年会

作者： ZHAI MingGuo~* Key Laboratory of Mineral Resources,Institute of Geology and Geophysics,chinese Academy of sciences,beijing 100029,china

Cratonization is a key geological process to form stable continental masses with a considerable *** Precambrian global cratonization and formation of supercratons in the world is an unrepeated event in the history of the Earth’s formation and *** based on study of early Precambrian geology in Eastern Hebei Region and combining other Archean regions in the North china Craton(NCC),the author proposes a two-stage cratonization model of the *** first stage took place at the end of Neoarchean of～2.5 Ga(boundary time between Archean and Proterozoic),when several micro-blocks were amalgamated together with amphibohte-granuhte facies metamorphism and intrusion of crustal-melting granites to form the present-scale *** second cratonization event is cratonic reworking,corresponding to rifting-subduction-collision at 2.3-1.97 Ga and subsequent extension-uplifting related to upwelling mantle at 1.97-1.82 Ga,which could be linked to,respectively, assembly and breaking up of the Columbia *** main Paleoproterozoic mobile belts in the NCC record that small remnant Neoarchean ocean basins and continental rift basins within the craton were opened and finally closed, and metamorphosed to greenschist-amphibolite facies at～2.0-1.97 *** that,high-grade granulite facies(HT-HP and HT-UHT) metamorphism with abnormally high heat occurred at 1.97-1.82 Ga.A metamorphism-migmatization event that includes lower crust of the NCC uplifting as a whole,intrusion of mafic dyke swarms,continental rifting and anorogenic magmatic action took place in 1.82-1.65 Ga,marking that the second cratonization of the NCC was finally accomplished and started to evolve to a period of stable continent(platform).

关键词： cratonization North china ancient continent

ADAPTIVE VARIABLE STRUCTURE CONTROLLERS AND APPLICATION TO ENGINE IDLE SPEED CONTROL SIMULATION

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chinese Journal of Mechanical Engineering 2003年第2期16卷 171-174页

作者： Hui Qing Quyang MinggaoState Key Laboratory of AutomotiveSafety and Energy,Tsinghua University,beijing 100084, china Tsinghua University State Key Laboratory of Automotive Safety and Energy 北京 100084

A neural-network-based adaptive variable structure control methodology isproposed for the tracking problem of nonlinear discrete-time input-output systems. The unknowndynamics of the system are approximated via radial basis function neural networks. The control lawis based on sliding modes and simple to implement. The discrete-time adaptive law for tuning theweight of neural networks is presented using the adaptive filtering algorithm with residueupper-bound compensation. The application of the proposed controller to engine idle speed controldesign is discussed. The results indicate the validation and effectiveness of this approach.

关键词： variable structure control adaptive control neural networks nonlineardiscrete-time systems idle speed control

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A study of the ionogram derived effective scale height around the ionospheric hmF2

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A study of the ionogram derived effective scale height aroun...

中国科学院地质与地球物理研究所2006学术年会

作者： Libo Liu,Weixing Wan,and Baiqi Ning Institute of Geology and Geophysics,chinese Academy of sciences,beijing 100029,china

The diurnal,seasonal,and solar activity variations of the ionogram derived scale height around the ionospheric F layer peak(Hm) are statistically analyzed at Wuhan(114.4°E, 30.6°N) and the yearly variations of Hm are also investigated for Wuhan and other 12.stations where Hm data is ***,as a measure of the slope of the topside electron number density profiles,is calculated from the bottomside electron density profiles derived from vertical sounding ionograms using the UMLCAR *** indicate that the value of median Hm increases with increasing solar *** is highest in summer and lowest in winter during the daytime,while it exhibits a much smaller seasonal variation at night.A common feature presented at these 13 stations is that,Hm undergoes a yearly annual variation with a maximum in summer during the *** annual variation becomes much weak or disappears from late night to *** addition,a moderate positive correlation is found between Hm with hmF2 and a strong correlation between the bottomside thickness parameter B0 and *** later provides a new and convenient way for empirical modeling the topside ionospheric shape only from the established B0 parameter set.

关键词： ionosphere scale height electron profile annual variation

Impact of East Asian winter monsoon on rainfall over southeastern china and its dynamical process

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Impact of East Asian winter monsoon on rainfall over southea...

作者： Lian-Tong Zhou* Center for Monsoon System Research,Institute of Atmospheric Physics,chinese Academy of sciences,beijing,china

The present study investigates the impact of the East Asian winter monsoon(EAWM) on winter(January, February,and March,or JFM in short) rainfall over southeastern china(including South china and central eastern china) and its dynamical process by using station observations for the period 1951-2003 and the ERA-40 reanalysis for the period *** is found that there is a significant correlation between interannual variations of the EAWM and JFM rainfall over southeastern *** show that in weak EAWM years southwesterly anomalies at 700 hPa dominate over South china Sea,which transports more moisture into southeastern china,favouring rainfall *** the same time,the East Asian westerly jet weakens and displaces southward,contributing to the increase in ascending motion over southeastern *** air temperature over southeastern china shows an obvious decrease at 300 hPa and increase near the *** enhances the convective instability and weakens the potential vorticity(PV),which explains the strengthening of ascending motion and the increase in JFM rainfall over southeastern *** addition,the EAWM has impacts independent of El Nino Southern Oscillation(ENSO) on JFM rainfall over southeastern ***,the rainfall anomalies over central eastern china are more closely related to the EAWM than that in South *** ? 2010 Royal Meteorological Society

关键词： EAWM rainfall convective instability potential vorticity

Heading date QTL in rice derived from an analysis of chromosome segment substitution lines

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Heading date QTL in rice derived from an analysis of chromos...

第十一届全国植物基因组学大会

作者： Yongsheng Zhang~(+1),Ling Jiang~(+1),Xi Liu~1,Shijia liu~1,Liangming Chen~1,Huqu Zhail~3,Jianmin Wan~(1,2,*) 1 State Key Laboratory of Crop Genetics and Germplasm Enhancement/Jiangsu Plant Gene Engineering Research Center,Nanjing Agricultural University,Nanjing 210095,china 2 Institute of Crop sciences,chinese Academy of Agricultural sciences,beijing 100081,china 3 chinese Academy of Agricultural sciences,beijing,china

The inheritance of heading date in rice was investigated using a set of lines in which chromosome segments of the photoperiod-and temperature-sensitive male sterile line Peiai 64S had been incorporated into a genetic ...

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Intermittent hypobaric hypoxia protects the heart against ischemia-reperfusion injury through activation of α1-adrenoceptors

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中国病理生理杂志 2012年第11期 2020-2021页

作者： GAO Ling1,CHEN Le1,LU Zhi-zhen2,ZHANG You-yi 2,ZHANG Cai-mei1,CHEN Yi-xiong1,YANG Huang-tian1(1Key Laboratory of Stem Cell Biology and Laboratory of Molecular Cardiology,Institute of Health sciences,Shanghai Institutes for Biological sciences,chinese Academy of sciences,Shanghai 200025,china 2Institute of Vascular Medicine,Peking University Third Hospital & Key Laboratory of Molecular Cardiovascular sciences Ministry of Education,beijing 100191,china)

AIM:Cumulated evidence have shown that intermittent hypobaric hypoxia(IHH)can protect the heart against ischemia-reper-fusion(I/R)injury by improving major manifestations such as infarct size,post-ischemic contractile... 详细信息

关键词： Intermittent hypobaric hypoxia protects the heart against ischemia-reperfusion injury through activation of adrenoceptors AIM MMP

Poroelastic wave equation including the Biot/squirt mechanism and the solid/fluid coupling anisotropy

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Poroelastic wave equation including the Biot/squirt mechanis...

中国科学院地质与地球物理研究所2002学术年会

作者： Dinghui Yang~a,Zhongjie Zhang~b a.Department of Mathematical sciences,Tsinghua University,beijing 100084,PR china. b.Institute of Geophysics,chinese Academy of sciences,beijing 100101,PR china

There is relative motion and inertial coupling between solids and fluids during seismic and acoustic propagation in rocks with *** inertial coupling is anisotropic because of the microvelocity anisotropy of the fluid relative to solid in an anisotropic *** Biot mechanism and the squirt-flow mechanism are the two most important mechanisms of solid/fluid interaction in *** extend the Biot/squirt(BISQ) theory to include the solid/fluid coupling anisotropy and develop a general poroelastic wave equation including both mechanisms *** new model estimates velocity/frequency dispersion and attenuation of waves propagating in the 2D PTL (periodicthinlayers)+EDA(extensive dilatancy anisotropy) medium with *** attenuation and dispersion of the two quasi-P-waves and the quasi-SV-wave,which are related to the solid/fluid coupling density and the permeability tensors,are *** anisotropy are simultaneously affected by the anisotropics of the solid skeleton,the permeability,and the solid/fluid coupling effect of the *** modeling suggests that variations of attenuation of both the fast quasi-P-wave and the quasi-SV-wave strongly depend on the permeability *** the low-frequency range,the maximum attenuation is in the direction of the maximum permeability for the fast quasi-P-wave and in the direction of the minimum permeability for the *** attenuation behaviors of the two waves in the high-frequency range,however,are opposite to those in the low-frequency *** paper also presents numerically how the attenuation and velocity dispersion of both the fast quasi-P-wave and the quasi-SV-wave are influenced by the anisotropic solid/fluid coupling *** model results demonstrate when the wave propagation is perpendicular to the direction of maximum solid/fluid coupling density,the wave motion exhibits maximum attenuation(Q-1) and maximum velocity dispersion for the fast quasi-P-wave,and m

关键词： Poroelastic wave equation Biot/squirt anisotropy