关于Fejer点上的一种复有理型插值的一致逼近阶

设D是一个Jordan,Г为其边界，并设Г满足Aльпер条件。本文得到了一种基于Fejer点的有理型插值算子对于f(z)∈C（Г）的一致逼近阶。     

On the Rank of the Semigroup TE(X)

${\cal T}_X $ denotes the full transformation semigroup on a set $ X $. For a nontrivial equivalence $E$ on $X$, let \[ T_E (X) =\{ f\in {\cal T}_X : \forall \, (a,b)\in E,\, (af,bf)\in E \} . \] Then $T_E (X) $ is exactly the semigroup of continuous selfmaps of the topological space $X$ for which the collection of all $E$-classes is a basis. In this paper, we first discuss the rank of the homeomorphism group $G$, and then consider the rank of $T_E (X)$ for a special case that the set $X$ is finite and that each class of the equivalence $E$ has the same cardinality. Finally, the rank of the closed selfmap semigroup $\Gamma(X)$ of the space $X$ is observed. We conclude that the rank of $G$ is no more than 4, the rank of $T_E (X)$ is no more than 6 and the rank of $\Gamma(X)$ is no more than 5.     

Decomposition of a hierarchy of nonlinear evolution equations

The generalized Hamiltonian structures for a hierarchy of nonlinear evolution equations are established with the aid of the trace identity. Using the nonlinearization approach, the hierarchy of nonlinear evolution equations is decomposed into a class of new finite-dimensional Hamiltonian systems. The generating function of integrals and their generator are presented, based on which the finite-dimensional Hamiltonian systems are proved to be completely integrable in the Liouville sense. As an application, solutions for the hierarchy of nonlinear evolution equations are reduced to solving the compatible Hamiltonian systems of ordinary differential equations.     

Decentered twisted Gaussian Schell-model beams and their propagation through a misaligned first-order optical system

The propagation properties of decentered twisted Gaussian Schell-model (DTGSM) beams passing through a misaligned first-order optical system are studied. The explicit expressions for the cross-spectral density function and Wigner distribution function of the output beam are derived, which retain their form unchanged. It is shown that the DTGSM beams preserve their closed property. The second-order moments matrix and the Wigner distribution function evolve with the usual laws, whereas the first-order moments matrix varies, as if a ray passes through such system. The propagation of DTGSM beams through an aligned first-order optical system is treated as the limiting case that corresponds to the vanishing misalignment parameters.     

Flow-injection spectrophotometric determination of sulfadiazine and sulfamethoxazole in pharmaceuticals and urine.

A rapid and sensitive flow-injection spectrophotometric method is proposed for the determination of sulfadiazine and sulfamethoxazole. This method is based on the diazotization of sulfonamide with sodium nitrite, and a coupling reaction of the diazo-compound with alpha-naphthylamine. The optimum experimental conditions are obtained by using the controlled and weighted centroid simplex method. The linear ranges for the determination of sulfadiazine and sulfamethoxazole are 0.2-20 microg ml(-1) and 0.1-20 microg ml(-1), and their detection limits are 0.06 microg ml(-1) and 0.05 microg ml(-1), respectively, and the sampling frequency is 130 samples per hour. The method has been used to determine sulfadiazine and sulfamethoxazole in pharmaceuticals and urine without separation. The results are in agreement with those obtained by a high-performance liquid chromatograph technique at the 95% confidence level.     

The complex correlation between current density and pore density based on non-SCR effects

The controllability of pore density and diameter is critical for emerging applications, e.g., non-lithographic photonic-crystal formation; however pore density and diameter could either increase or decrease self-orderedly with enhanced current density. In this letter, similar paradoxical phenomena were demonstrated; the etch rate as a function of field strength was evidenced and interpreted in light of current-burst-model. Based on a hybrid of SCR (space charge region) and breakdown effects, a semi-quantitative model was established in order to disentangle the paradox: such a model could also potentially serve as a design reference for various applications as far as breakdown comes into play. The paradox was finally found to be dominated by physics on patterned samples.     

关于三维Minkowski空间中直线汇的一些注记

本文研究了三维Minkowski空间中直线汇的一些性质,特别是关于类时线汇的性质．讨论了线汇基本元素的存在性,并证明了关于三维Minkowski空间中类时线汇的配分参数的一个结果,推广了苏步青1927年的—个成果．     

多重向量值正交小波包

本文引入多重向量值小波包的概念,提供一类多重向量值正交小波包的构造方法,并运用积分变换和算子理论,讨论了多重向量值正交小波包的性质．利用多重向量值正交小波包,构造了空间L2(R,Cs×s)的新的正交基．     

IPv4/IPv6翻译网关的研究

In this paper, a model of translation gateway is proposed. The communications between IPv4 network and IPv6 network are realized by using the Microsoft intermediate driver technology in environment of Windows 2000.