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1.
Chen Yongnian 《模糊系统与数学》1995,(1)
ANTIFUZZYVECTORSPACES(Ⅱ)ChenYongnian(DepartmentofMathematics,XinjiangNormalUniversity,830054,Xinjiang,P.R.China)ANTIFUZZYVECT... 相似文献
2.
Uncertainty about the nature and significance of nonlinearities and the manner in which dynamics affect future realizations makes model specification the most difficult aspect of modeling dynamic systems. By interpreting several popular fishery models as subcases of a nesting dynamic Taylor series approximation, we isolate the specification differences between these models in a way that accounts for commonalities. On the argument that the differences due to alternative nonlinear forms are likely to be small compared to more mundane considerations such as delay difference and general dynamic lag specification, we propose an alternative model that uses the terms from the first order approximation common to all models combined with a data-based determination of the appropriate lags using the methods of state space time series analysis. Finally, the success of the alternative models is judged in an application to Pacific halibut data. 相似文献
3.
4.
桂质廷(1895~1961),我国著名的地球物理学家.他是建国初期中国科学院地球物理组专门委员,第一个巡测了我国境内地磁常量的中国人.他最先和学生一道在国内进行了高空电离层的常规观测.他所创建的武汉大学游离层实验室,50年来未曾间断电离层的观测研究.本文着重介绍他的生平简历、教学态度、学术成就和爱国主义思想. 相似文献
5.
Nazakat Ullah 《Pramana》1993,41(2):171-174
A formulation is developed to derive exact analytic expressions for electron-electron correlation and density of electrons
in momentum space using hydrogenic wave functions. It is shown that for large atoms the expression for density of electrons
has a simple form. 相似文献
6.
There are 281 subgroups of index 4 for the 17 types of 2-dimension space groups: p1:7, p2:31, pm:19, pg:7, cm:11, p2mm:67, p2mg:23, p2gg:11, c2mm:31, p4:11, p4mm:31, p4gm:11, p3:4, p3m1:4, p31m:4, p6:4, p6mm:5. Every subgroup has been identified by its conventional cell disposition with respect to the conventional cell of the starting group. These subgroups may be arranged in 96 automorphism classes and 184 conjugation classes according to their starting groups. 相似文献
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8.
研究了参数型Marcinkiewicz积分高阶交换子并证明了其从H1b(Rn)到L1(Rn)有界,其中b∈BMO. 相似文献
9.
John D. Ramshaw 《Journal of statistical physics》1989,56(1-2):149-158
Phase space density representations of inviscid fluid dynamics were recently discussed by Abarbanel and Rouhi. Here it is shown that such representations may be simply derived and interpreted by means of the Liouville equation corresponding to the dynamical system of ordinary differential equations that describes fluid particle trajectories. The Hamiltonian and Poisson bracket for the phase space density then emerge as immediate consequences of the corresponding structure of the dynamics. For barotropic fluids, this approach leads by direct construction to the formulation presented by Abarbanel and Rouhi. Extensions of this formulation to inhomogeneous incompressible fluids and to fluids in which the state equation involves an additional transported scalar variable are constructed by augmenting the single-particle dynamics and phase space to include the relevant additional variable. 相似文献
10.