一种参数曲线间Hausdorff距离的计算方法

针对一般的连续参数曲线,提出一种快速计算曲线间Hausdorff距离的方法.由于曲线的近似折线能很好的表示曲线,所以,许多软件中,采用曲线的近似折线绘制曲线.为此,证明了在任意给定误差范围下,可以将曲线间的Hausdorff距离转化为折线间的Hausdorff距离,进一步转化为点到线段间的距离进行计算,并辅之必要的剪枝策略和增量式算法以提高计算效率.该方法计算速度快,逼近度高,基本解决了参数曲线间Hausdorff距离的计算问题,在几何设计、图像匹配、图像识别等领域有广泛应用.     

关于m+1分非均匀Cantor集的Hausdorff测度的充分必要条件

本文考虑由一类线性迭代系统产生的多分非均匀Cantor集,讨论了这类非均匀Cantor集的几何结构,获得了相关的性质,给出了这类多分非均匀Cantor集Hausdorff测度的一个充分必要条件。     

On the Universal Curve in Superplasticity Mechanics

We have carried out a series of tests (tensile, compression, torsion, and tension+torsion) of a superplastic titanium alloy VT9 at 950°C, with strain-rate intensity _e = 5 10^-4 - 1 10^-2 s ^-1 . By plotting and analyzing the stress intensity vs strain-rate intensity curves for this material, we justified the validity of the universal curve hypothesis for finite strains with an accuracy acceptable in engineering practice.     

Hausdorff矩问题的解

本文利用矩阵论的方法研究Hausdorff矩问题。     

On the Representation of Turbulent Stresses for Computing Blood Damage

Computational prediction of blood damage has become a crucial tool for evaluating blood-wetted medical devices and pathological hemodynamics. A difficulty arises in predicting blood damage under turbulent flow conditions because the total stress is indeterminate. Common practice uses the Reynolds stress as an estimation of the total stress causing damage to the blood cells. This study investigates the error introduced by making this substitution, and further shows that energy dissipation is a more appropriate metric of blood trauma.     

On the Way to Determination of the Vapor-Pressure Curve of Pure Water

The determination of the physical properties of pure water, especially the vapor-pressure curve of water, is one of the major issues identified by the Consultative Committee for Thermometry of the International Committee for Weights and Measures (CIPM) to improve the accuracy of the national references in humidity. At the present time the saturation-pressure data, corresponding to ice or liquid?Cvapor equilibrium, at low temperature are scarce and unreliable. This study presents new measurements of vapor and sublimation pressures of, respectively, water and ice, using a static apparatus. Prior to saturation-pressure measurements, the temperature and pressure sensors of the static apparatus were calibrated against reference gauges in use at the LNE- CETIAT laboratories. The effect of thermal transpiration has been studied. The explored temperature range lies between 250 K and 374 K, and the pressure range between 70?Pa and 10⁵ Pa. An automatic data acquisition program was developed to monitor the pressure and temperature. The obtained results have been compared with available literature data. The preliminary uncertainty budget took into account several components: pressure measurements, temperature measurements, and environmental error sources such as thermal transpiration and hydrostatic correction.     

论量值溯源和量值传递

介绍量值溯源及量值传递的定义,论述两者之间的关系。     

用分析－数值法求解非线性包装系统的产品破损边界曲线

应用非线性动力学方程的分析－数值解法，推导了矩形冲击时非线性包装系统的破损边界曲线，研究了非线性项对破损边界曲线的影响，分析了影响破损边界曲线安全区范围大小的因素。     

以标准化手段助推广州云计算落地发展

本文综述了广州市云计算发展现状及存在问题,并在此基础上,结合标准化实践经验,提出了加快广州云计算落地发展的相关建议,以期在全球云计算信息变革中,能为广州抢占云计算产业发展制高点,提高国家中心城市竞争力,建设智慧广州提供参考。     

Sierpinski垫片的Hausdorff测度的下界

本文证明 Sierpinski垫片 S的 H ausdorff测度满足 Hs(S)≥ 13     

论公共行政价值的层次性

公共行政价值是一个关系范畴，包括价值主体的需要、价值客体的活动和行为以及价值客体的活动和行为对价值主体需要的满足关系。公共行政价值是公共行政学的重要研究课题，同时明确公共行政价值，对于公共行政实践具有重要的指导意义。文章认为公共行政价值由三个层次构成：作为基础性价值的秩序、作为核心价值的效率以及作为终极价值的正义。