On the operator of exterior derivation on the Riemannian manifolds with cylindrical ends

We formulate some conditions for the normal and compact solvability of the operator of exterior derivation on the cylindrical manifolds equipped with some Riemannian metrics. Some analogous results were obtained in the particular case of warped cylinders [1].     

Banach空间中不适定线性算子方程的最佳逼近解

设X,Y为Banach空间,T为从X到Y的线性算子.T的值域R(T)≠Y且为逼近紧子空间,T的零空间N(T)≠{θ}.证得不适定算子方程Tx=y的最佳逼近解对任意y∈Y均存在的充分必要条件是N(T)为X的迫近子空间.     

连续小波在医学图像处理中的一种应用

本文构造了一类具有紧支撑的无限次可导的对称小波，提出了适应医学图像处理的边缘检测算法，并给出了计算实例。     

Unique crystalline structure and performance of poly(ethylene terephthalate) melt spun fibers

Modification of the threadline dynamics has effected significant alternations in the structure and improvements in the properties of high-speed melt spun poly(ethylene terephthalate) (PET) fibers. Key process parameters extant in the threadline dynamics, such as temperature, tensile stress, and deformation time, were independently controlled through proper implementation of on-line perturbations. The placement of a liquid isothermal bath in close proximity to the spinneret in the melt spinning threadline provided tremendous increase in the spinning stress while at the same time controlled the filament temperature corresponding to development of the desired fiber structure. Characterization of the fiber structure and physical properties has been carried out using birefringence measurements, density, shrinkage, x-ray diffraction, DSC, FTIR spectroscopy, and tensile tests. The results provided sufficient evidence to support the existence of a unique crystalline morphology that led to the significantly improved tensile properties and excellent dimensional stability of the resulting fibers. This unique crystalline morphology was typically characterized by the presence of a larger amount of extended chain segments and an enhanced molecular connectivity. ©1995 John Wiley & Sons, Inc.     

Numerical simulation of free shear flows and far-field sound pressure directivity

An implicit spatial differencing technique with fourth-order accuracy has been developed based on the Pade compact scheme. A dispersion-relation-preserving concept has been incorporated into the numerical scheme. Two-dimensional Euler computation of a spatially developing free shear flow with and without external excitation has been performed to demonstrate the capability of the numerical scheme developed. Results are in good agreement with theory and experimental observation regarding the growth rate of the fluctuating velocity, the convective velocity and the vortex-pairing process. The far-field sound pressure generated by the computed shear flow solution using Lighthill's acoustic analogy shows a strong directivity with a zone of silence at the flow angle.     

非紧致一秩对称空间上某种极大函数的可和性

ＮｏěｌＬｏｈｏｕé证明了复对称空间上某种极大函数ｆ＋（ｘ）＝ｓｕｐｔ＞０（１＋ｔ）３２｜Ｐｔｆ（ｘ）｜的可和性可归结为‖（Δ０）１２ｆ‖（ｘ）的可和性．作者证明了上述结果对奇数维实双曲空间成立．由于偶数维实双曲空间的热核表达式不同，因此有必要对偶数维实双曲空间的情形单独给出证明．本文的目的就是证明上述结果对偶数维实双曲空间亦成立．     

Few remarks and questions on pseudoradial and related spaces

Some new results concerning pseudoradial and related spaces are presented. Particular emphasis is given to the class of semiradial spaces. In addition, some known facts are collected in order to provide motivations for various questions.     

纱线动态加捻的理论研究 第二部分:对一些理想加捻过程的分析

在前文即第一部分中已推导了动态加捻的基本方程和捻度的波动方程,并讨论了它们的动力学特征。在这一部分中则将利用上述基本方程和结论,分析一些典型理想加捻过程,包括加捻的过渡过程以及传统纺纱和自由端纺纱的稳态加捻问题。     

Fixed Point Theorems for Increasing Operators of None－continuity and None－compactness Conditions

ＦｉｘｅｄＰｏｉｎｔＴｈｅｏｒｅｍｓｆｏｒＩｎｃｒｅａｓｉｎｇＯｐｅｒａｔｏｒｓｏｆＮｏｎｅ－ｃｏｎｔｉｎｕｉｔｙａｎｄＮｏｎｅ－ｃｏｍｐａｃｔｎｅｓｓＣｏｎｄｉｔｉｏｎｓＺｈａｎｇＱｉｎｇｚｈｅｎｇ（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉｃｓ，...