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41.
Java自发布以来 ,作为一种面向对象的程序设计语言深受广大计算机业者的青睐。而Java2的出现使得支持应用程序开发的环境日益成熟 ,表现在超强的数据处理能力与网络集成开发能力 ,以及由于其跨平台能力和可移植性所带来人机交互能力与分布式计算能力。正是由于后者 ,给出一个非线性规划算法解决一个飞行管理问题。 相似文献
42.
This work deals with the global existence of weak solutions for a Kazhikhov–Smagulov type system with a density which may or not vanish. Our model is formally equivalent to the physical compressible model with Fick’s law, in contrast to those in previous works. This model may be used for addressing environmental problems such as propagation of pollutants and avalanche modelling. We also explain why this system may be seen as a physical regularization of the standard nonhomogeneous incompressible Navier–Stokes equations and we give an existence result with an initial density less regular but away from the vacuum. 相似文献
43.
HeSuxiang HanHua 《高校应用数学学报(英文版)》2005,20(2):243-251
The dual algorithm for minimax problems is further studied in this paper. The resulting theoretical analysis shows that the condition number of the corresponding Hessian of the smooth modified Lagrange function with changing parameter in the dual algorithm is proportional to the reciprocal of the parameter,which is very important for the efficiency of the dual algorithm. At last ,the numerical experiments are reported to validate the analysis results. 相似文献
44.
713C天气雷达的回波强度定标 总被引:5,自引:3,他引:2
为了抵消天气雷达的参数变化所引起的雷达回波强度的误差 ,根据天气雷达回波强度定标的基本原理 ,结合我们多年来在天气雷达的参数测量、系统调整及回波强度定标中累积的经验 ,将详细地论述 713C天气雷达回波强度定标的内在过程 :给出了回波强度定标的软件流程、介绍了雷达定标前的准备工作及定标过程、说明了 713C天气雷达回波强度定标文件的形成方法、又提出了几种对天气雷达定标结果的验证方法。这样才能使得定标后天气雷达残存的回波强度误差在整个接收系统对数动态线性范围内控制在 2dB以内 ,保证天气雷达定量探测降水回波的准确性 相似文献
45.
从力敏传感器测力的原理出发,总结了用力敏传感器测量液体表面张力系数实验的诸多优点,并阐述了这个实验的现实意义. 相似文献
46.
对随机位相屏产生的动态散斑可以根据照明方式及光路设计方法进行分类研究。根据T.Yoshimura的文章所提出的理论公式,我们对高斯光束照明的单透镜成像系统的动态散斑进行了实验测量。实验证明理论公式正确,实验结果与理论予期值符合也说明我们所使用的实验方法可行。在实验过程中,我们提出一种新的拟合方法,从而解决了实验常数的确定问题。 相似文献
47.
Pilar Izu María Eugenia Muoz Juan J. Pea Anton Santamaría 《Journal of Polymer Science.Polymer Physics》1993,31(3):347-356
Viscosity measurements on two commercial thermotropic liquid crystalline polymers (LCPs) (a copolyester and a polyesteramide) were performed using both capillary and slit die methods. The results are in agreement with those presented in the literature for the same LCPs, when the measurements are carried out with a L/D = 30 die; these results are affected more by Bagley corrections for the polyesteramide than for the copolyester. For both LCPs, viscosities measured in the slit die are lower than those obtained by capillary rheometry. Nevertheless, the difference is much bigger in the case of the polyesteramide, for which a reduction by a factor of 3 is observed. This is not due to the preshear or thermal history, since the same piston-barrel system and thermal treatment were applied in both types of measurements. Depending on the polymer sample and temperature, concave and convex curvatures were observed in the pressure profiles during the slit flow. From these curvatures, the pressure coefficient α of viscosity was evaluated. However, in the case of the polyesteramide the convex curvature leads to a negative coefficient (the viscosity decreases with pressure, instead of increasing). This result may be explained by envisaging a change in the structure of the melt along the slit length. © 1993 John Wiley & Sons, Inc. 相似文献
48.
Yong Ding Senhua Lan 《分析论及其应用》2006,22(4):339-352
Let A be a symmetric expansive matrix and Hp(Rn) be the anisotropic Hardy space associated with A. For a function m in L∞(Rn), an appropriately chosen function η in Cc∞(Rn) and j ∈ Z define mj(ξ) = m(Ajξ)η(ξ). The authors show that if 0 < p < 1 and (m)j belongs to the anisotropic nonhomogeneous Herz space K11/p-1,p(Rn), then m is a Fourier multiplier from Hp(Rn) to Lp(Rn). For p = 1, a similar result is obtained if the space K10,1(Rn) is replaced by a slightly smaller space K(w).Moreover, the authors show that if 0 < p ≤ 1 and if the sequence {(mj)V} belongs to a certain mixednorm space, depending on p, then m is also a Fourier multiplier from Hp(Rn) to Lp(Rn). 相似文献
49.
Shijun Zheng 《分析论及其应用》2006,22(4)
Let H be a Schr(o)dinger operator on Rn. Under a polynomial decay condition for the kernel of its spectral operator, we show that the Besov spaces and Triebel-Lizorkin spaces associated with H are well defined. We further give a Littlewood-Paley characterization of Lp spaces in terms of dyadic functions of H. This generalizes and strengthens the previous result when the heat kernel of H satisfies certain upper Gaussian bound. 相似文献
50.
The authors consider a model of ferromagnetic material subject to an electric current, and prove the local in time existence of very regular solutions for this model in the scale of Hk spaces. In particular, they describe in detail the compatibility conditions at the boundary for the initial data. 相似文献