共查询到20条相似文献,搜索用时 15 毫秒
1.
耦合径向基函数与多项式基函数的无网格方法 总被引:3,自引:1,他引:2
耦合径向基函数和多项式基函数,形成一种新的近似函数.该近似函数对散乱分布的离散数据点进行逼近时,只需节点信息,不需要划分网格.详细描述了耦合近似函数的建立、属性、插值行为及其形函数和形函数导数的性质.最后引入修正变分原理和单位分解积分技术求解边值问题,并给出了计算实例,表明耦合径向基函数和多项式基函数是一种非常有效的方法. 相似文献
2.
We prove that a pair-potential which is continuous,L
1, and of positive type satisfies a condition of the superstability kind with best-possible constants. The applications to statistical thermodynamics are mentioned. 相似文献
3.
W e i-Norm an分解对于分析矩阵微分方程的解是比较成熟的理论,含有幺正演化矩阵的薛定谔方程是矩阵微分方程,所以可以利用W e i-Norm an分解来分析求出多能级量子系统的解。由于W e i-Norm an分解适用的范围是小时间变化的邻域,为了求出量子系统在任意时刻的幺正演化矩阵,根据量子系统的特性,提出了对量子系统的控制时间进行分段,利用W e i-Norm an分解来获得每段小时间的幺正演化矩阵。最后通过一个两能级的例子进行仿真,根据实验结果总结出该量子系统的状态与控制场作用之间的关系。 相似文献
4.
In this Letter, we present a new approach to the notion of hypergeometric functions. 相似文献
5.
The equation of state(EOS) for hard-sphere fluid derived from compressibility routes of Percus-Yevick theory(PYC) is extended. The two parameters are determined by fitting well-known virial coefficients of pure fluid.The extended cubic EOS can be directly extended to multi-component mixtures, merely demanding the EOS of mixtures also is cubic and combining two physical conditions for the radial distribution functions at contact(RDFC) of mixtures.The calculated virial coefficients of pure fluid and predicted compressibility factors and RDFC for both pure fluid and mixtures are excellent as compared with the simulation data. The values of RDFC for mixtures with extremely large size ratio 10 are far better than the BGHLL expressions in literature. 相似文献
6.
The equation of state (EOS) for hard-sphere fluid derived from compressibility routes of Percus-Yevick theory (PYC) is extended. The two parameters are determined by fitting well-known virial coefficients of pure fluid. The extended cubic EOS can be directly extended to multi-component mixtures, merely demanding the EOS of mixtures also is cubic and combining two physical conditions for the radial distribution functions at contact (RDFC) of mixtures. The calculated virial coefficients of pure fluid and predicted compressibility factors and RDFC for both pure fluid and mixtures are excellent as compared with the simulation data. The values of RDFC for mixtures with extremely large size ratio 10 are far better than the BGHLL expressions in literature. 相似文献
7.
去除图像中的椒盐噪声可转化为二维曲面的重建问题。选用Multi-Quadric函数对图像中损失的信息构造插值格式,自动选择待插值点和插值参考点并求解插值方程组得到处理后的图像。实验证明,本方法可以在很少破坏图像细节的情况下去除大部分甚至全部噪声,并且在噪声密度非常大的情况下仍然可以还原相当多的图像信息。对噪声密度为50%和90%的单色Lena图像进行处理,该方法得到的信噪比比自适应中值滤波高6dB以上。 相似文献
8.
Suphawat Asawasamrit Muhammad Aamir Ali Sotiris K. Ntouyas Jessada Tariboon 《Entropy (Basel, Switzerland)》2021,23(8)
Quantum information theory, an interdisciplinary field that includes computer science, information theory, philosophy, cryptography, and entropy, has various applications for quantum calculus. Inequalities and entropy functions have a strong association with convex functions. In this study, we prove quantum midpoint type inequalities, quantum trapezoidal type inequalities, and the quantum Simpson’s type inequality for differentiable convex functions using a new parameterized q-integral equality. The newly formed inequalities are also proven to be generalizations of previously existing inequities. Finally, using the newly established inequalities, we present some applications for quadrature formulas. 相似文献
9.
For classical transformation (q1,q2) → (Aq1 + Bq2, Cq1 + Dq2), where AD - CB ≠ 1, we find its quantum mechanical image by using LDU decomposition of the matrix (A B C D ). The explicit operators L, D, and U axe derived and their physical meaning is revealed, this also provides a new way for disentangling some exponential operators. 相似文献
10.
In the framework of event-enhanced quantum theory the dynamical equation for the reduced density matrix of a quantum system interacting with a continuous classical system is derived. The asymptotic behavior of the corresponding dynamical semigroup is discussed. The example of a quantum–classical coupling on Lobatchevski space is presented. 相似文献
11.
Devvrat Tiwari Kavalambramalil G. Paulson Subhashish Banerjee 《Annalen der Physik》2023,535(2):2200452
In this article, single, and two-qubit central spin systems interacting with spin baths are considered and their dynamical properties are discussed. The cases of interacting and non-interacting spin baths are considered and the quantum speed limit (QSL) time of evolution is investigated. The impact of the size of the spin bath on the quantum speed limit for a single qubit central spin model is analyzed. The quantum correlations for (non-)interacting two central spin qubits are estimated and their dynamical behavior with that of QSL time under various conditions are compared. How QSL time could be availed to analyze the dynamics of quantum correlations is shown. 相似文献
12.
用原子分子反应静力学与群论的方法,推导了AlH、AlD及AlT的基电子状态为1Σ+。在QCISD/6-311G水平上对氢化铝进行了计算,导出了其MurrelSorbie势能函数,并计算了氢同位素分子及其铝化物的能量E和熵S。设用总能量中的电子和振动能量近似代表AlH、AlD和AlT分子处于固态时的能量,用总熵中的电子和振动熵近似代表这些分子处于固态时的熵,进而计算了铝吸附H2,D2和T2分子过程的ΔH°,ΔS°,ΔG°和平衡压力,并导出它们与温度的函数关系,计算指出了同位素分子效应,结果合理。 相似文献
13.
The negativity of the discrete Wigner functions (DWFs) is a measure of non-classicality and is often used to quantify the degree of quantum coherence in a system. The study of Wigner negativity and its evolution under different quantum channels can provide insight into the stability and robustness of quantum states under their interaction with the environment, which is essential for developing practical quantum computing systems. The variation of DWF negativity of qubit, qutrit, and two-qubit systems under the action of (non)-Markovian random telegraph noise (RTN) and amplitude damping (AD) quantum channels is investigated. Different negative quantum states that can be used as a resource for quantum computation and quantum teleportation are constructed. The success of quantum computation and teleportation is estimated for these states under (non)-Markovian evolutions. 相似文献
14.
15.
Kari Ylinen 《Foundations of Physics》2009,39(6):656-675
The notion of an instrument in the quantum theory of measurement is studied in the context of transformation valued linear
maps on von Neumann algebras and their *-subalgebras. An extension theorem is proved which yields among other things characterizations of the Fourier transforms of
instruments and their noncommutative analogues. As an application, an ergodic type theorem for a general class of transformation
valued functions on a locally compact group is obtained. 相似文献
16.
Jiangbo Wang Jianghua Fang Jiarong Wang Haoqi Gao 《Journal of Macromolecular Science: Physics》2013,52(8):1525-1536
The thermal decomposition kinetics of epoxy resin (EP) containing polyepoxyphenylsilsesquioxane (PEPSQ) was studied by thermogravimetric analysis (TGA) in a nitrogen atmosphere. Kissinger and Flynn–Wall–Ozawa methods were both used to analyze the thermal decomposition process under nonisothermal conditions. The results showed that a slight increase of activation energy was observed in the presence of PEPSQ, which indicated that the addition of PEPSQ retarded the thermal decomposition of EP. The Flynn–Wall–Ozawa method further revealed that PEPSQ significantly increased the activation energy of the whole EP thermal decomposition, especially in the final stage of the thermal decomposition process, which is attributed to the PEPSQ stabilizing the char layer and improving the flame retardancy of EP. 相似文献
17.
We develop the theory of operators defined on a space of holomorphic functions. First, we characterize such operators by a suitable space of holomorphic functions. Next, we show that every operator is a limit of a sequence of convolution and multiplication operators. Finally, we define the exponential of an operator which permits us to solve some quantum stochastic differential equations. 相似文献
18.
By means of devices of geometric algebra the general decomposition of spin connection on the sphere bundle of a compact n-dimensional Riemannian manifold has been studied in detail. Using this decomposition theory it is shown that the Gauss-Bonnet-Cherniensity of the Euler-PoincarB characterictic can be expressed in terms of a smooth vector field φ and take the form of the 6 function δ(φ). The topological structure in Gauss-Bonnet-Chern theorem is reviewed. 相似文献
19.
LIN Qiong-Gui 《理论物理通讯》2006,45(5):919-922
In quantum mechanics the center of a wave packet is precisely defined as the center of probability. The center-of-probability velocity describes the entire motion of the wave packet.
In classical physics there is no precise counterpart to the
center-of-probability velocity of quantum mechanics, in spite of the fact that there exist in the literature at least eight different velocities for
the electromagnetic wave. We propose a center-of-energy velocity to
describe the entire motion of general wave packets in classical
physical systems. It is a measurable quantity, and is well defined
for both continuous and discrete systems. For electromagnetic wave
packets it is a generalization of the velocity of energy transport.
General wave packets in several classical systems are studied and the
center-of-energy velocity is calculated and expressed in terms of the
dispersion relation and the Fourier coefficients. These systems
include string subject to an external force, monatomic chain and
diatomic chain in one dimension, and classical Heisenberg model in
one dimension. In most cases the center-of-energy velocity reduces to
the group velocity for quasi-monochromatic wave packets. Thus it also
appears to be the generalization of the group velocity. Wave packets
of the relativistic Dirac equation are discussed briefly. 相似文献
20.
The aim of this paper is to calculate the binary and triplet distribution functions for one and two component Plasmas in terms of Green's function technique. We obtained the triplet distribution function in two form; one of them is based on the Kirkwood Superposition Approximation (KSA) which is consisting of the assumption that the potential in a set of three particles is the sum of the three pair potentials, this is equivalent to assuming that the triplet distribution function is the product of the three binary distribution functions, but the other form is calculated from BBGKY hierarchy. (© 2014 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献