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141.
More recently, sixteen families of Jacobian elliptic function solutions of mKdV equation have been foundby using our extended Jacobian elliptic function expansion method. In this paper, we continue to improve our methodby using another eight pairs of the closed Jacobian elliptic functions. The mKdV equation is chosen to illustrate theimproved method such that another eight families of new Jacobian elliptic function solutions are obtained again. Thenew method can be more powerful to be applied to other nonlinear differential equations.  相似文献   
142.
In this paper, we give some evaluation formulas for Tornheim's type of alternating series by an elementary and combinatorial calculation of the uniformly convergent series. Indeed, we list several formulas for them by means of Riemann's zeta values at positive integers.

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143.
This note investigates two long-standing conjectures on the Krull dimension of integer-valued polynomial rings and of polynomial rings in the context of (locally) essential domains.

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144.
We use frequency-dependent capacitance–voltage spectroscopy to study the dynamic charging of self-assembled InAs quantum dots. With increasing frequency, the AC charging becomes suppressed, beginning with the low-energy states. By applying an in-plane magnetic field, we generate an additional magnetic confinement that alters the tunneling barrier and hence the charging dynamics. In traveling through the potential barrier, the electrons acquire an additional momentum k0, proportional to the magnetic field B. As the tunneling is enhanced, when k0 matches the maximum of the electronic wave function Ψ (in momentum representation), we are able to map out the shape of Ψ by varying B.  相似文献   
145.
双核系统核子转移驱动势与复合核的最佳激发能   总被引:2,自引:1,他引:1  
计算了以208Pb为靶的一系列重离子熔合反应双核系统核子转移驱动势.它制约由输运方程所支配的核子转移速率,因而确定了双核系统形成复合核的几率.并由此可确定形成复合核所必须的最低激发能,即形成最稳定复合核的最佳激发能,得到了与已知实验值基本符合的结果. Particle transfer driven potentials in Di nuclear System (DNS) in heavy ion collisions based on 208Pb target are calculated. The driven potential controls the particle transfer velocity in the process governed by the diffusion equation, and as a consequence determines the compound nuclear formation probability of DNS. The minimum excitation energy to form a compound nucleus, which is the optimum excitation energy to form the most stable compound nucleus, has been calculated, and the results are basica...  相似文献   
146.
In this paper, we investigate the exact distribution of the waiting time for ther-th ℓ-overlapping occurrence of success-runs of a specified length in a sequence of two state Markov dependent trials. The probability generating functions are derived explicitly, and as asymptotic results, relationships of a negative binomial distribution of orderk and an extended Poisson distribution of orderk are discussed. We provide further insights into the run-related problems from the viewpoint of the ℓ-overlapping enumeration scheme. We also study the exact distribution of the number of ℓ-overlapping occurrences of success-runs in a fixed number of trials and derive the probability generating functions. The present work extends several properties of distributions of orderk and leads us a new type of geneses of the discrete distributions.  相似文献   
147.
By using the methods of the matrix decomposition and expansion of the hard-edged aperture function into a finite sum of complex Gaussian functions, the recurrence propagation expressions for a flattened Gaussian beam (FGB) through multi-apertured optical imaging systems of B = 0 are derived and illustrated with numerical examples. Comparisons with the straightforward numerical integration of the Collins formula and with the previous work are made. It is shown that the main advantages of our methods and results are the more accuracy and great reduction of computer time.  相似文献   
148.
Two structure functions W1(x,Q2) and W2(x,Q2) are determined by using the cross sections measured in the deep inelastic electron-proton scattering experiments at Stanford Linac in the energy range of 5 to 20 GeV. In this paper an alternative mathematical approach have been used in such determination, resulting in a larger number of points in the graphs of the structure functions.  相似文献   
149.
射束有效宽度与成像系统MTF关系的研究   总被引:1,自引:0,他引:1  
邵军明  路宏年  候涛 《光学技术》2003,29(2):242-244
射线成像系统的射线有效宽度是评定系统成像分辨率的重要成像指标。以试验的方法,通过测试系统成像的MTF,通过对成像分辨率与射线有效宽度的关系进行研究,为射线数字成像(DR)及工业CT系统设计提供了参考。  相似文献   
150.
压缩偶相干态的制备及其非经典特性   总被引:12,自引:3,他引:9       下载免费PDF全文
嵇英华 《物理学报》2003,52(2):332-336
通过保持非耗散介观LC电路的固有频率不变,而使电路参数作阶跃函数变化,就可将介观LC电路由初始的偶相干态制备到压缩偶相干态;在压缩偶相干态下,介观电路系统不仅有非经典的量子压缩效应,而且有非经典的反聚束效应. 关键词: 介观LC电路 单位阶跃函数 压缩算符 压缩偶相干态  相似文献   
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