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| 1 | Shock solution for quasilinear singularly perturbed Robin problem显示文摘The shock solution for the quasilinear singularly perturbed Robin problem is considered. Under suitable conditions and using the theory of differential inequalities the existence and asymptotic behavior of the shock solution for the original boundary value problems are studied. | MO Jiaqi and WANG Hui(1. Anhui Normal University, Wuhu 241000, China 2. National Natural Science Foundation of China, Beijing 100085, China) | 2002 | Progress in Natural Science:Materials International2002，12，12： | 70 |
| 2 | 完全匹配层吸收边界条件研究显示文摘为了提高人为截断边界的吸收效率,提出了一种完全匹配层边界吸收衰减因子——正、余弦型吸收衰减因子。采用声波波动方程,并应用统一格式的高阶交错网格有限差分法来构建正演递推算子实现声波全波场正演计算(边界处差分阶数依次递减)。以单层均匀介质模型为例,研究不同吸收层厚度与介质速度和声波模拟主频的关系。数值试算结果表明,不同吸收层厚度所消耗的时间按一定的函数关系变化,边界吸收层厚度与速度和最大频率之间无明确的对应关系,边界吸收层厚度所占节点数不小于6个时就可以得到较好的边界吸收效果。以Marmousi模型为例研究了完全匹配层边界吸收衰减因子在复杂地质模型中的边界吸收效果,与解析解的对比可知,该边界吸收衰减因子能在复杂地质模型中取得满意的边界吸收效果。 | 陈可洋 | 2010 | 石油物探2010，49，5： | 63 |
| 3 | A CLASS OF NONLOCAL BOUNDARY VALUE PROBLEMS OF NONLINEAR ELLIPTIC SYSTEMS IN UNBOUNDED DOMAINS显示文摘The nonlocal boundary value problems for nonlinear elliptic systems in the unbounded domain are considered. Under suitable conditions the existence of solution and comparison theorem for the boundary value problems are studied. | 莫嘉琪 欧阳成 | 2001 | Acta Mathematica Scientia2001，21，1： | 64 |
| 4 | A CLASS OF SINGULARLY PERTURBEDBOUNDARY VALUE PROBLEMS FOR NONLINEARDIFFERENTIAL SYSTEMS显示文摘The singularly perturbed nonlinear problem εy' = f(x, y’)y + g(x, y’), 0 | MO Jiaqi (Department of Mathematics, Anhui Normal University, Wuhu 241000, China) | 1999 | Systems Science and Mathematical Sciences1999，12，1： | 51 |
| 5 | Carbon isotope excursions across the Permian-Triassic boundary in the Meishan section, Zhejiang Province, China显示文摘Both gradual and sharp decrease in organic and carbonate carbon isotope values were detected across the Permian-Triassic boundary in the Meishan section, Changxing, Zhejiang Province, China. The gradual decrease in organic carbon isotope values started at the bottom of Bed 23, coinciding with the strong oscillations of total organic carbon (TOC) contents, indicates increasing fluxes from carbonate to organic carbon reservoir during this interval. A 2.3‰ sharp drop of inorganic carbon isotope values occurred at the uppermost part of Bed 24e. A 3.7‰ sharp drop of organic carbon isotope values occurred in Bed 26. The dramatic drop of inorganic carbon isotope value of 8‰ reported previously is not confirmed from the unweathered carbonate samples in Bed 27. The large-scale fluctuation of organic carbon isotope values in the Yinkeng Formation reflects different extent of mixing of marine and terrestrial organic matters. The gradual depletion and subsequent sharp drop of carbon isotopes near the | Changqun Cao Wei Wang Yugan Jin | 2002 | Chinese Science Bulletin2002，47，13： | 33 |
| 6 | A CLASS OF SINGULARLY PERTURBED REACTION DIFFUSION INTEGRAL DIFFERENTIAL SYSTEM显示文摘In this paper a class of singularly perturbed initial boundary value problems for the reaction diffusion integral differential system are considered. Using the iteration method and the differential inequalities, the existence, uniqueness and its asymptotic behavior of solution for the initial boundary value problems are studied. | 莫嘉琪 | 1999 | Acta Mathematicae Applicatae Sinica1999，15，1： | 31 |
| 7 | A boundary value problem for hypermonogenic functions in Clifford analysis显示文摘This paper deals with a boundary value problem for hypermonogenic functions in Clifford analysis. Firstly we discuss integrals of quasi-Cauchy's type and get the Plemelj formula for hypermonogenic functions in Clifford analysis, and then we address Riemman boundary value problem for hypermonogenic functions. | QIAO Yuying | 2005 | Science China Mathematics2005，48，z1： | 29 |
| 8 | SIMS U-Pb zircon age of a tuff layer in the Meishucun section, Yunnan, southwest China: Constraint on the age of the Precambrian-Cambrian boundary显示文摘Determination of the age of the Precambrian-Cambrian boundary is critical in understanding early evolution of life on Earth. SIMS U-Pb zircon analyses of the Bed 5 tuff layer of the Meishucun section were carried out closely following the guidance of cathodoluminescence images, and the majority of analyses were conducted on the oscillatory zircon grains. Thirteen measurements yield a highly reliable Concordia U-Pb age of 536.7 ± 3.9 Ma for the Bed 5 horizon. A grand mean of 206Pb/238U age of 535.2± 1.7 Ma (MSWD = 0.53) is calculated based on 13 concordant SIMS measurements of this study and 4 nano-SIMS measurements of Sawaki et al., which is the best estimate of the deposition age of the tuff layer within Bed 5 in the Meishucun section. This age has provided a robust age constraint on the significant Precambrian-Cambrian boundary strata in southern China, which independently suggested the placement of the Precambrian-Cambrian boundary at the bottom of the Xiaowaitoushan Member (Marker A). | RiXiang Zhu XianHua Li XianGuang Hou YongXin Pan Fei Wang ChengLong Deng HuaiYu He | 2009 | Science China Earth Sciences2009，52，9： | 24 |
| 9 | Direct numerical simulation of shock/turbulent boundary layer interaction in a supersonic compression ramp显示文摘A direct numerical simulation of the shock/turbulent boundary layer interaction flow in a supersonic 24-degree compression ramp is conducted with the free stream Mach number 2.9.The blow-and-suction disturbance in the upstream wall boundary is used to trigger the transition.Both the mean wall pressure and the velocity profiles agree with those of the experimental data,which validates the simulation.The turbulent kinetic energy budget in the separation region is analyzed.Results show that the turbulent production term increases fast in the separation region,while the turbulent dissipation term reaches its peak in the near-wall region.The turbulent transport term contributes to the balance of the turbulent conduction and turbulent dissipation.Based on the analysis of instantaneous pressure in the downstream region of the mean shock and that in the separation bubble,the authors suggest that the low frequency oscillation of the shock is not caused by the upstream turbulent disturbance,but rather the instability of separation bubble. | LI XinLiang1,FU DeXun2,MA YanWen2 & LIANG Xian1 1 Key Laboratory of High Temperature Gas Dynamics,Institute of Mechanics,Chinese Academy of Sciences,Beijing 100190,China 2 The State Key Laboratory of Nonlinear Mechanics,Institute of Mechanics,Chinese Academy of Sciences,Beijing 100190,China | 2010 | Science China(Physics,Mechanics & Astronomy)2010，53，9： | 24 |
| 10 | Dynamic dam-reservoir interaction analysis including effect of reservoir boundary absorption显示文摘Based on the scaled boundary finite-element method, the governing equations for the analysis of dam-reservoir interaction including the reservoir boundary absorption are developed. Coupling with the equation of dam-unbounded foundation interaction, it can effectively carry out the earthquake response analysis of dameservoir-foundation system. The proposed approach has the advantages that the effect of compressibility of reservoir water as well as the energy absorption of reservoir boundary on the earthquake response of arch dams and gravity dams can be efficiently evaluated and higher accuracy can be achieved. In comparison with the methods available in the literature, the computational cost can be reduced to a great extent. It facilitates the application of earthquake response analysis of dam-reservoir-foundation system including reservoir boundary absorption to the engineering practice. | LIN Gao DU JianGuo HU ZhiQiang | 2007 | Science China(Technological Sciences)2007，50，z1： | 23 |
| 11 | The mechanism of breakdown in laminar-turbulent transition of a supersonic boundary layer on a flat plate-temporal mode显示文摘Temporal mode direction numerical simulation has been done for the transition of a supersonic boundary layer on a flat plate with Mach number 4.5. Analysis of the result showed that during the breakdown process in laminar-turbulent transition, the mechanism causing the mean flow profile to evolve swiftly from laminar to turbulent was that the modification of mean flow profile by the disturbances,when they became larger,led to a remarkable change of its stability characteristics. Though the most unstable T-S wave was of second mode for laminar flow, the first mode waves played the key role in the breakdown process in laminar-turbulent transition. | HUANG Zhangfeng 1, CAO Wei 1,2 & ZHOU Heng 1,2 1. Department of Mechanics, Tianjin University, Tianjin 300072, China 2. Liu-Hui Center of Applied Mathematics, Nankai University and Tianjin University, Tianjin 300072, China | 2005 | Science China(Physics,Mechanics & Astronomy)2005，48，5： | 23 |
| 12 | Numerical simulations of self-propelled swimming of 3D bionic fish school显示文摘Numerical simulations of self-propelled swimming of a three dimensional bionic fish and fish school in a viscous fluid are carried out. This is done with the assistance of a parallel software package produced for 3D moving boundary problems. This computational fluid dynamics package combines the adaptive multi-grid finite volume method, the immersed boundary method and VOF (volume of fluid) method. By using the package results of the self-propelled swimming of a 3D bionic fish and fish school in a vis- cous fluid are obtained. With comparison to the existing experimental measurements of living fishes, the predicted structure of vortical wakes is in good agreement with the measurements. | WU ChuiJie1 & WANG Liang2 1 State Key Laboratory of Structural Analysis for Industrial Equipment, Dalian University of Technology, Dalian 116024, China 2 Research Center for Fluid Dynamics, People’s Liberation Army University of Science and Technology, Nanjing 211101, China | 2009 | Science China(Technological Sciences)2009，52，3： | 23 |
| 13 | THE PHYSICAL STRUCTURE OF THE WINTER FOG IN CHONGQING METROPOLITAN AREA AND ITS FORMATION PROCESS显示文摘Chongqing is a very famous foggy metropolitan in China.The Chongqing Fog Experiment Group carried out com-prehensive experiments on a large and extensive scale in the Chongqing urban area from 15 December 1989 to 15 Janua-ry 1990.And several items were further observed from 7 December 1990 to 7 January 1991.Based on the analysis of theobservational data,some important characteristics of the Chongqing winter fog and the boundary layer structure havebeen revealed.It is found that such factors as topography,mountain wind,rivers,the urban heat island and airpollution,all contribute to the formation of the Chongqing fog in addition to the radiation conditions. | 李子华 张利民 张庆鸿 | 1994 | Acta meteorologica Sinica1994，8，3： | 23 |
| 14 | Genetic Contribution of Paleopolyploidy to Adaptive Evolution in Angiosperms显示文摘Ancient whole-genome duplications (WGDs or polyploidy) are prevalent in plants, and some WGDs occurred during the timing of severe global environmental changes. It has been suggested that WGDs may have contributed to plant adaptation. However, this still lacks empirical evidence at the genetic level to support the hypothesis. Here, we investigated the survivors of gene duplicates from multiple ancient WGD events on the major branches of angiosperm phylogeny, and aimed to explore genetic evidence supporting the significance of polyploidy. Duplicated genes co-retained from three waves of independent WGDs (~120 million years ago [Ma], ~66, and <20 Ma) were investigated in 25 selected species. Gene families functioning in low temperature and darkness were commonly retained gene duplicates after the eight independently occurring WGDs in many lineages around the Cretaceous-Paleocene boundary, when the global cooling and darkness were the two main stresses. Moreover, the commonly retained duplicates could be key factors which may have contributed to the robustness of the critical stress-related pathways. In addition, genome-wide transcription factors (TFs) functioning in stresses tend to retain duplicates after waves of WGDs, and the coselected gene duplicates in many lineages may play critical roles during severe environmental stresses. Collectively, these results shed new light on the significant contribution of paleopolyploidy to plant adaptation during global environmental changes in the evolutionary history of angiosperms. | Shengdan Wu Baocai Han Yuannian Jiao | 2020 | Molecular Plant2020，13，1： | 21 |
| 15 | Magma underplating and Hannuoba present crust-mantle transitional zone composition: Xenolith petrological and geochemical evidence显示文摘On the basis of mineral assemblage, mineralogy, petrology, and major, trace ele-mental and isotopic geochemistry of the underplated granulite- and eclogite-facies accumulate, peridotite and pyroxenite xenoliths entrained in Hannuoba Cenozoic basalts, this work con-strained the petrological constituents for the crust-mantle transitional zone, which is supported by the results of high-temperature and pressure velocity experiments on rocks and geophysics deep survey. Present lower part of lower crust is mainly composed of granulite-facies mafic accumu-lates (dominantly plagioclase websterite) and crust-mantle transitional zone dominantly com-posed of eclogite-facies pyroxenites with or without garnet and spinel lherzolites; Archaean ter-rain granulite is only nominally early lower crust. Magma underplating in the crust-mantle boundary led to the crustal vertical accretion and the formation of the crust-mantle transitional zone, which is a significant mechanism for the chemical adjustment of the crust-mantle boundary since the Phanerozoic. | FAN Qicheng1,2, ZHANG Hongfu1, SUI Jianli1, ZHAI Mingguo1, SUN Qian2 & LI Ni2 1. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 2. Institute of Geology, China Seismological Bureau, Beijing 100029, China | 2005 | Science China Earth Sciences2005，48，8： | 20 |
| 16 | Nonlinear boundary value problem for biregular functions in Clifford analysis显示文摘The biregular function in Clifford analysis is discussed. Plemelj’s formula is obtained andnonlinear boundary value problem: is considered. Applying the methodof integral equations and Schauder fixed-point theorem, the existence of solution for the above problem is proved. | 黄沙 | 1996 | Science China Mathematics1996，39，11： | 19 |
| 17 | Microbialite of anoxic condition from Permian-Triassic transition in Guizhou,China显示文摘Spherical microfossils are present in the Hindeodus parvus zone of the Lower Triassic in Ziyun,Guizhou Province. They generally range from 0.15 to 0.30 mm across,with micritic wall and filled by micro-sparry calcites,and are evenly scattered in micritic matrix. Their abundance makes the rock as-signed to microbialites. The accompanied organisms include ostracods and algal mat,but no gastro-pods or bivalves. Presence of small (<7 μm) pyrite framboids indicates that this bed formed in anoxic conditions. In some sections,this bed is overlain and underlain by tidal-flat micritic limestone with microgastropods and small burrows. Occurrence only in deposits on reef top indicates that the micro-bial organism was benthic,and needed sunlight in life. The size of the microbial fossil exceeds that of any bacteria or cyanobacteria. Thus,it does not belong to these two phyla. It may belong to lower green algae,and is assigned to a new species in a new genus,Ziyunosphaeridium sinensis gen. et sp. nov. Up to now,the rocks described as microbialites from the Permian-Triassic transition include six types: (1) porous micritic limestone such as that descried from Japan by Sano and Nakashima (1997),(2) limestone with rich globular microfossils such as that described from the Nanpanjiang Basin in China by Lehrmann (1999),(3) dendroidal limestone such as that described from the vicinity of Chongqing by Kershaw et al. (1999),(4) spherical microbial limestone adapted to anoxic environments described from Ziyun,Guizhou reported in this paper,(5) limestone with cyanobacterial fossils such as that described by Wang et al. (2005),and (6) stromatolites. All these microbialites are not reefs in the proper sense,and the argument that Permian reef ecosystems extended into the Mesozoic is incorrect. | WU YaSheng JIANG HongXia YANG Wan FAN JiaSong | 2007 | Science China Earth Sciences2007，50，7： | 18 |
| 18 | On the Controllability of an Advection-diffusion Equation with Respect to the Diffusion Parameter:Asymptotic Analysis and Numerical Simulations显示文摘The advection-diffusion equation y_t~ε-εy_(xx)~ε+ M y_x~ε= 0,(x, t) ∈(0, 1) ×(0, T) is null controllable for any strictly positive values of the diffusion coefficient ε and of the controllability time T. We discuss here the behavior of the cost of control when the coefficient ε goes to zero, according to the values of T. It is actually known that this cost is uniformly bounded with respect to ε if T is greater than a minimal time T_M, with T_M in the interval [1, 2×3^(1/2)]/M for M > 0 and in the interval [2×2^(1/2), 2(1 +3^(1/2))]/|M | for M < 0. The exact value of TM is however unknown.We investigate in this work the determination of the minimal time T_M employing two distincts but complementary approaches. In a first one, we numerically estimate the cost of controllability, reformulated as the solution of a generalized eigenvalue problem for the underlying control operator, with respect to the parameter T and ε. This allows notably to exhibit the structure of initial data leading to large costs of control. At the practical level, this evaluation requires the non trivial and challenging approximation of null controls for the advection-diffusion equation. In the second approach, we perform an asymptotic analysis, with respect to the parameter ε, of the optimality system associated to the control of minimal L^2-norm. The matched asymptotic expansion method is used to describe the multiple boundary layers. | Youcef AMIRAT Arnaud MNCH | 2019 | Acta Mathematicae Applicatae Sinica2019，35，1： | 18 |
| 19 | ON SOLUTION OF A KIND OF RIEMANN BOUNDARY VALUE PROBLEM WITH SQUARE ROOTS显示文摘Solution of the Riemann boundary value problem with square roots (1.1) for analytic functions proposed in [1] is reconsidered, which was solved under certain assumptions on the branch points appeared. Here the work is continued without these assumptions and the problem is solved in the general case. | 路见可 | 2002 | Acta Mathematica Scientia2002，22，2： | 18 |
| 20 | The Influences of Boundary Layer Parameterization Schemes on Mesoscale Heavy Rain System显示文摘The mesoscale numerical weather prediction model (MM4) in which the computations of the turbulentexchange coeffcient in the boundary layer and surface fluxes are improved, is used to study the influences ofboundary layer parameterization schemes on the predictive results of the mesoscale model. Seven differentexperiment schemes (including the original MM4 model) designed in this paper are tested by theobservational data of several heavy rain cases so as to find an improved boundary layer parameterizationscheme in the mesoscale meteorological model. The results show that all the seven different boundary layerparameterization schemes have some innuences on the forecasts of precipitation intensity, distribution ofrain area. vertical velocity. vorticity and divergence fields, and the improved schemes in this paper can improve the precipitation forecast. | 许丽人 赵鸣 | 2000 | Advances in Atmospheric Sciences2000，17，3： | 17 |
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