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GRACE时变重力场的高斯平滑研究 被引量:9
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作者 周新 邢乐林 +1 位作者 邹正波 李辉 《大地测量与地球动力学》 CSCD 北大核心 2008年第3期41-45,共5页
利用各向同性和非各向同性两种GRACE时变重力场平滑方法试算了2006年1月至2月的全球大地水准面变化。研究表明,非各向同性的高斯滤波器的频谱不仅依赖于阶也依赖于次,但能够提高纬度方向的分辨率,在经度方向的分辨率和各向同性滤波器的... 利用各向同性和非各向同性两种GRACE时变重力场平滑方法试算了2006年1月至2月的全球大地水准面变化。研究表明,非各向同性的高斯滤波器的频谱不仅依赖于阶也依赖于次,但能够提高纬度方向的分辨率,在经度方向的分辨率和各向同性滤波器的相当;计算得到了与各向同性高斯平滑同精度的时变重力场反演结果。 展开更多
关键词 GRACE时变重力场 高斯平滑 非各向同性 频谱 大地水准面
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非均质岩体爆破设计方案优化 被引量:5
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作者 陈亚军 《煤炭技术》 CAS 北大核心 2012年第5期71-72,共2页
在非均质岩体露天矿山的爆破设计和施工中,由于忽略了爆破网路的安全性和合理性,造成炮区拒爆和出现爆破安全事故。因此,对爆破设计方案进行优化,可以有效提高爆破效果,增加爆破作业的安全性。
关键词 非均质 爆破设计 优化
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MIXED LEGENDRE-HERMITE PSEUDOSPECTRAL METHOD FOR HEAT TRANSFER IN AN INFINITE PLATE 被引量:4
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作者 Tian-jun Wang Ben-yu Guo 《Journal of Computational Mathematics》 SCIE EI CSCD 2005年第6期587-602,共16页
A new mixed Legendre-Hermite interpolation is introduced. Some approximation results are established. Mixed Legendre-Hermite pseudospectral method is proposed for non-isotropic heat transfer in an infinite plate. Its ... A new mixed Legendre-Hermite interpolation is introduced. Some approximation results are established. Mixed Legendre-Hermite pseudospectral method is proposed for non-isotropic heat transfer in an infinite plate. Its convergence is proved. Numerical results show the efficiency of this approach. 展开更多
关键词 non-isotropic heat transfer Infinite plate Mixed Legendre-Hermite pseudospectral method
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Poincaré and Sobolev Inequalities for Vector Fields Satisfying Hrmander's Condition in Variable Exponent Sobolev Spaces 被引量:2
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作者 Xia LI Guo Zhen LU Han Li TANG 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2015年第7期1067-1085,共19页
In this paper, we will establish Poincare inequalities in variable exponent non-isotropic Sobolev spaces. The crucial part is that we prove the boundedness of the fractional integral operator on variable exponent Lebe... In this paper, we will establish Poincare inequalities in variable exponent non-isotropic Sobolev spaces. The crucial part is that we prove the boundedness of the fractional integral operator on variable exponent Lebesgue spaces on spaces of homogeneous type. We obtain the first order Poincare inequalities for vector fields satisfying Hormander's condition in variable non-isotropic Sobolev spaces. We also set up the higher order Poincare inequalities with variable exponents on stratified Lie groups. Moreover, we get the Sobolev inequalities in variable exponent Sobolev spaces on whole stratified Lie groups. These inequalities are important and basic tools in studying nonlinear subelliptic PDEs with variable exponents such as the p(x)-subLaplacian. Our results are only stated and proved for vector fields satisfying Hormander's condition, but they also hold for Grushin vector fields as well with obvious modifications. 展开更多
关键词 Poincare inequalities the representation formula fractional integrals on homogeneousspaces vector fields satisfying Hormander's condition stratified groups high order non-isotropic Sobolev spaces with variable exponents Sobolev inequalities with variable exponents
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鱼雷声纳自噪声及环境噪声仿真及其应用 被引量:1
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作者 杨云川 崔怀林 李志舜 《计算机仿真》 CSCD 2004年第9期10-13,共4页
环境噪声与航行噪声通过其强度对自噪声级的影响与方向性对基阵阵增益的影响 ,降低了鱼雷自导分辨率并增大估计误差 ,对鱼雷自导工作性能有着严重的影响。该文通过对鱼雷自导航行自噪声与环境噪声的仿真与试验研究 ,对半实物仿真航行自... 环境噪声与航行噪声通过其强度对自噪声级的影响与方向性对基阵阵增益的影响 ,降低了鱼雷自导分辨率并增大估计误差 ,对鱼雷自导工作性能有着严重的影响。该文通过对鱼雷自导航行自噪声与环境噪声的仿真与试验研究 ,对半实物仿真航行自噪声与环境噪声的方案进行了论证与分析 ,讨论了各向同性噪声场与非各向同性噪声场的空间相关性与仿真生成的方法 。 展开更多
关键词 噪声场 仿真 自噪声 环境噪声 各向同性 非各向同性 鱼雷声纳
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High frequency S wave envelope synthesis using a multiple non-isotropic scattering model: application to aftershocks from the 2008 Wenchuan earthquake 被引量:1
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作者 Lin Gao Jing Yueling Li Jianbo 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2013年第2期185-194,共10页
Based on the formulation of a multiple non-isotropic scattering process, a characteristic source time is introduced to define the initial impulse width of energy density at the source. An analytical expression of the ... Based on the formulation of a multiple non-isotropic scattering process, a characteristic source time is introduced to define the initial impulse width of energy density at the source. An analytical expression of the initial intensity spectral density of a seismic wave is incorporated into the integral equation of seismic wave energy density. And, a recursive formula of Green's function is derived to obtain the higher order Green's function, which is included to describe the stronger non-isotropic scattering process. Then, the effect of the scattering pattern on the energy density envelope is investigated by the modified scattering theory. Significant differences arc found in the decay of the energy density envelopes with distances using different scattering patterns. The envelope synthesized by the forward dominated scattering pattern is larger than the results obtained by the isotropic and backward dominated scattering pattern. Different scattering patterns are also used to fit the observation data from the aftershocks of the 2008 Wenchuan earthquake. It is concluded that the envelopes synthesized by the forward scattering pattern can match the data better than the isotropic and backward dominated scattering cases, and a new interpretation of the coda wave is given. Finally, using the forward dominated scattering pattern, the envelope broadening of the observed data is reproduced. 展开更多
关键词 non-isotropic scattering coda wave envelope broadening energy transport theory (radiative transfer theory) directional scattering coefficient ground motion
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热分层湍流计算机模拟的数学模型研究 被引量:1
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作者 高殿武 赵春刚 顾泽元 《黑龙江矿业学院学报》 1999年第3期26-30,39,共6页
以湍流标准k-ε模型为基础,综合考虑代数应力模型(ASM)及湍流热流输运方程,建立了热分层流动的热浮力湍流修正数学模型。理论及在液纳空腔内的热分层湍流计算机模拟中的应用表明,该模型在一程度上反映了由于流动过程中温度不均而... 以湍流标准k-ε模型为基础,综合考虑代数应力模型(ASM)及湍流热流输运方程,建立了热分层流动的热浮力湍流修正数学模型。理论及在液纳空腔内的热分层湍流计算机模拟中的应用表明,该模型在一程度上反映了由于流动过程中温度不均而导致的各向异性特征,并为解决热分层流中温度随时间变化的计算机模拟难题提供了一个较为简单、稳定的模型。 展开更多
关键词 热分层 热浮力 湍流模型 各向异性 计算机模拟
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Rough Marcinkiewicz Integrals with Mixed Homogeneity on Product Spaces
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作者 Feng LIU Huo Xiong WU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2013年第7期1231-1244,共14页
In this paper, the parabolic Marcinkiewicz integral operators on the product spaces R^m × R^n(m, n ≥ 2) are studied. The LP-boundedness for such operators are established under rather weak size conditions of t... In this paper, the parabolic Marcinkiewicz integral operators on the product spaces R^m × R^n(m, n ≥ 2) are studied. The LP-boundedness for such operators are established under rather weak size conditions of the kernels, which essentially improve or extend certain previous results. 展开更多
关键词 Marcinkiewicz integrals non-isotropic dilations maximal functions rough kernels product spaces
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A NON-ISOTROPIC MULTIPLE-SCALE TURBULENCE MODEL
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作者 陈谦斌 郭宽良 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1991年第10期981-991,共11页
This paper describes a newly developednon-isotropic multiple-scale turbulence model (MS/ASM) for complex flow calculations. This model focuses on the direct modeling of Reynolds stresses and utilizes split-spectrum co... This paper describes a newly developednon-isotropic multiple-scale turbulence model (MS/ASM) for complex flow calculations. This model focuses on the direct modeling of Reynolds stresses and utilizes split-spectrum concepts to model multiple-scale effects in turbulence. Validation studies on free shear flows, rotating flows and recirculating flows show that the current model performs significantly better than the single-scale k-e model. The present model is relatively inexpensive in terms of CPU time which makes in suitable for broad engineering flow applications. 展开更多
关键词 turbulence model multiple-scale non-isotropic
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Initial-boundary Value Problem for a Class of Quasilinear Degenerate Parabolic Equations
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作者 Nie Lei Xu Chaojiang 《Wuhan University Journal of Natural Sciences》 CAS 1996年第2期179-183,共5页
in this work,we study the quasilinear initial-boundary value problem , where is a system of real smooth vector fields which is defined on an open domain M of R'', and satisfies the Hormanderls condition,.Assu... in this work,we study the quasilinear initial-boundary value problem , where is a system of real smooth vector fields which is defined on an open domain M of R'', and satisfies the Hormanderls condition,.Assume that is non characteristic for the system X,,..',Xm. Under some hypothesis for the boundary of domain and the elliptic structure condition for nonlinear coerfficients Aij, Bj, C,(i, j= 1, ..', m), we have proved that the existence and regularity of solution for aboveinitialboudary value problems. 展开更多
关键词 degenerate parabolic equation vector fields non-isotropic Holder's space initial-boundary value problem
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Non-isotropic weighted L^p estimates for the -equation on piecewise smooth strictly pseudoconvex domains
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作者 Heungju AHN Hong Rae CHO Jong-Do PARK 《Science China Mathematics》 SCIE 2008年第12期2161-2171,共11页
In this paper we obtain non-isotropic weighted Lp estimates with the boundary distance weight function for the-equation on piecewise smooth strictly pseudoconvex domains under a hypoth- esis of complex transversality ... In this paper we obtain non-isotropic weighted Lp estimates with the boundary distance weight function for the-equation on piecewise smooth strictly pseudoconvex domains under a hypoth- esis of complex transversality in Cn using the explicit formula of solutions by Berndtsson-Andersson. 展开更多
关键词 non-isotropic norm Cauchy-Riemann EQUATION PIECEWISE strictly PSEUDOCONVEX domain
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Maximal Operators and Singular Integrals with Non-Isotropic Dilation on Product Domains
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作者 Zhong Kai LI Bo Lin MA Huo Xiong WU 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2010年第10期1847-1864,共18页
In this paper, the authors study the with non-isotropic dilation on product domains. LP-mapping properties of certain maximal operators As an application, the LP-boundedness of the corre- sponding nomisotropic multipl... In this paper, the authors study the with non-isotropic dilation on product domains. LP-mapping properties of certain maximal operators As an application, the LP-boundedness of the corre- sponding nomisotropic multiple singular integral operator is also obtained. Here the integral kernel functions Ω belong to the spaces L(logL)a(E1 × E2) for some a 〉 0, which is optimal. 展开更多
关键词 non-isotropic singular integral maximal function product domain rough kernel
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Spatial Nonparametric Regression Estimation: Non-isotropic Case
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作者 Zu-di Lu, Xing ChenInstitute of Systems Science, Academy of Mathematics and Systems Sciences, Chinese Academy of Sciences. Beijing 100080, ChinaDepartment of Statistics, Yunnan University, Kunming 650091, China 《Acta Mathematicae Applicatae Sinica》 SCIE CSCD 2002年第4期641-656,共16页
Data collected on the surface of the earth often has spatial interaction. In this paper, a non-isotropic mixing spatial data process is introduced, and under such a spatial structure a nonparametric kernel method is s... Data collected on the surface of the earth often has spatial interaction. In this paper, a non-isotropic mixing spatial data process is introduced, and under such a spatial structure a nonparametric kernel method is suggested to estimate a spatial conditional regression. Under mild regularities, sufficient conditions are derived to ensure the weak consistency as well as the convergence rates for the kernel estimator. Of interest are the following: (1) All the conditions imposed on the mixing coefficient and the bandwidth are simple; (2) Differently from the time series setting, the bandwidth is found to be dependent on the dimension of the site in space as well; (3) For weak consistency, the mixing coefficient is allowed to be unsummable and the tendency of sample size to infinity may be in different manners along different direction in space; (4) However, to have an optimal convergence rate, faster decreasing rates of mixing coefficient and the tendency of sample size to infinity along each direction are required. 展开更多
关键词 Bandwidth kernel estimator mixing non-isotropic spatial data spatial conditional regression weak consistency and rates
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Bubble Tree ConVergence for the Harmonic Sequence of Harmonic Surfaces in CP^n
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作者 Xiao Huan MO Fang SUN 《Acta Mathematica Sinica,English Series》 SCIE CSCD 2010年第7期1277-1286,共10页
We show that any harmonic sequence determined by a harmonic map from a compact Riemannian surface M to CP^n has a terminating holomorphic (or anti-holomorphic) map from M to CP^n, or a "bubble tree limit" consisti... We show that any harmonic sequence determined by a harmonic map from a compact Riemannian surface M to CP^n has a terminating holomorphic (or anti-holomorphic) map from M to CP^n, or a "bubble tree limit" consisting of a harmonic map f: M → CP^n and a tree of bubbles hλ^μ: S^2 --→ CP^n. 展开更多
关键词 bubble tree harmonic sequence non-isotropic energy identity
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各向异性H^P(R^n)上的乘子定理(英文) 被引量:1
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作者 陆善镇 杨大春 周祖胜 《北京师范大学学报(自然科学版)》 CAS CSCD 北大核心 1997年第1期1-9,共9页
记t>0且1=α1≤α2≤…≤αn·设At=diag(t(α1)…,t(αn))是Rn\{0}上各向异性连续交换群.对L∞(Rn)中的函数m,以及适当选取的中的函数η和任意的δ>0,定义mδ(ξ)=m(Aδξ)η(ξ).证明了当0<P<1,且属于各向... 记t>0且1=α1≤α2≤…≤αn·设At=diag(t(α1)…,t(αn))是Rn\{0}上各向异性连续交换群.对L∞(Rn)中的函数m,以及适当选取的中的函数η和任意的δ>0,定义mδ(ξ)=m(Aδξ)η(ξ).证明了当0<P<1,且属于各向异性的Herz空间时,m是各向异性HP(Rn)上的乘子.进一步,当p=1时,如果将替换成一个稍小的空间K(ω),得到了类似的结论. 展开更多
关键词 各向异性 HERZ空间 乘子定理 哈代空间
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一种各向异性多重尺度的湍流模型 被引量:1
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作者 郭宽良 陈谦斌 《应用数学和力学》 EI CSCD 北大核心 1991年第10期917-925,共9页
本文给出了一种适用于复杂湍流流动计算的各向异性、多重尺度的湍流模型(MS/ASM).这种模型对雷诺应力进行直接的模拟,并可模拟湍流流动的多重尺度影响.对自由应力流动、旋转流动和回流的湍流流动的计算表明,它比常用的单重尺度的k-ε模... 本文给出了一种适用于复杂湍流流动计算的各向异性、多重尺度的湍流模型(MS/ASM).这种模型对雷诺应力进行直接的模拟,并可模拟湍流流动的多重尺度影响.对自由应力流动、旋转流动和回流的湍流流动的计算表明,它比常用的单重尺度的k-ε模型有明显的改进.由于计算机工作量增加得不多,所以它在工程计算中,具有广泛的应用前景. 展开更多
关键词 多重尺度 湍流模型 各向异性
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非标准增长拟线性椭圆型方程非平凡解的存在性
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作者 王向东 《河南科学》 1994年第4期267-274,共8页
应用没有P.S条件的广义越山引理证明了非标准增长的拟线性椭圆型方程非平凡解的存在性。
关键词 拟线性 椭圆型方程 存在性
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THE CHARACTERISTIC POLYNOMIAL OF A GEOMETRIC LATTICE IN SYMPLECTIC GEOMETRY OVER FINITE FIELDS
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作者 陈冬生 万哲先 《Chinese Science Bulletin》 SCIE EI CAS 1991年第12期974-978,共5页
Let F be a field and V= V<sub>n</sub>(F)={(a<sub>1</sub>,…, a<sub>n</sub>)|a<sub>i</sub>∈F} be the row vector space of finite dimension n over F. Let be a finite s... Let F be a field and V= V<sub>n</sub>(F)={(a<sub>1</sub>,…, a<sub>n</sub>)|a<sub>i</sub>∈F} be the row vector space of finite dimension n over F. Let be a finite set ofsubspaces of Vsuch that U=(0). And let L= L((?)) be the set of intersections of dements of. Partial order L by reverse inclusion has V as its minimal element and as its set of atoms. We denote the partial order- 展开更多
关键词 GEOMETRIC LATTICE non-isotropic SUBSPACE CHARACTERISTIC polynomial.
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房屋采用浅基础的探讨
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作者 丁学兴 《萍乡高等专科学校学报》 2007年第3期36-37,共2页
论述了采用浅基房屋的破坏机理,用公式计算了非均质土的地基承载力,可供设计人员参改。
关键词 房屋采用浅基础 非均质土层 承载力计算
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The Gagliardo-Nirenberg-Sobolev Inequality for Non-lsotropic Riesz Potentials
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作者 Inan Cinar 《Journal of Mathematics and System Science》 2015年第2期83-85,共3页
In this study, the inequality of Gagliardo-Nirenberg-Sobolev type are established for non-isotropic Generalized Riesz Potential depending on 2-distance.
关键词 non-isotropic distance POTENTIALS
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