费马大定理一个奇妙的证明

本文利用x+y=A和0相似文献   

Systematical Scrutiny into Special Relativity

This paper examines some basic propositions of the special relativity theory. A Gedanken experiment is proposed to disprove Einstein's light speed invariance; the 4-dimension invariant seems invalid because it is impossible for the time and spatial coordinate variables to be orthogonal, because of their presumed cross-correlations; and the Lorentz transformation is therefore bounded to have an intrinsic arbitrariness. In addition, the well-known topic of the "relativity of simultaneity" turns out to be a false proposition, because of at least one logical error made by Einstein that violates the two postulates of his own theory. Einstein's theory is flooded with vital errors and flaws, and must be reexamined thoroughly as soon as possible.     

Superconducting Properties and Microstructure in MgB2 Bulks, Wires and Tapes

We prepared a series of MgB2 bulk samples under different temperatures, holding time and increasing rates in temperature by the solid state reaction. The thermodynamic behavior and phase formation in the Mg-B system were studied by using DTA, XRD and SEM. The results indicate that the formation of the MgB2 phase is very fast and the high increasing rate in temperature is necessary to obtain high quality MgB2. In addition, the effects of the Zr-doping in Mg1-xZrxB2 bulk samples fabricated by the solid state reaction at ambient pressure on phase compositions, microstructure and flux pinning behavior were investigated by using XRD, SQUID magnetometer, SEM and TEM. Critical current density Jc can be significantly enhanced by the Zr-doping and the best data are achieved in Mg0.9Zr0.1B2. For this sample, Jc values are remarkably improved to 1. 83 × 106 A/cm2 in self-field and 5. 51 × 105 A/cm2in 1T at 20K. Also, high quality MgB2/Ta/Cu wires and tapes with and without Ti-doping, MgB2/Fe wires and 18 filamen     

带烧蚀发汗冷却控制研究的特点——兼评“发汗冷却控制研究数学模型”一文

本文指出带烧蚀发汗冷却控制研究三方面的特点。同时指出,由于理解上的不当,文献[2]所指文献[1]的错误是不存在的。     

Unification and Comparison between Two Concepts of Radar Target Angular Glint

This paper provides a general proof of unification between two concepts of radar target angular glint. The analysis of a two-point target model, consisting of a electrically and a magnetically ideal dipole, shows the relation, difference and equivalent condition between them more clearly. Angular glint has been synthesized from the measured data of radar echo phase, and compared with the theoretical result.     

紧支正交小波的参量化法和波数字滤波器

本文详细分析了小波变换，镜像滤波器（ｑｕａｄｒａｔｕｒｅｍｉｒｏｒｆｉｌｔｅｒ－ＱＭＦ）组和波数字滤波器散射矩阵之间的关系，提出了由散射矩阵的基本因子来构造镜像滤波器对，从而得出了具有任意消失矩的紧支正交小波的参量化法。并给出了基于正则性约束的参量优化和一个有效的实现小波变换的格型结构。     

Status and Perspectives of Process Systems Engineering

The definitions, methodology, applications, and perspectives of process systems engineering are discussed from a strategic point of view. The focal points in future development of process systems engineering are to break through in methodology, to expand application fields, and to develop a new generation of process simulation systems.     

关于烧蚀发汗控制方程及其数学仿真

本文提出二维加热且具有表面烧蚀的发汗控制物理模型。利用热层内微元能量平衡的原理,推导出活动边界分布参数控制方程式。给出了第三边值条件。得到了控制参数不仅出现在方程中,同时出现在边界条件中的分布参数控制系统。采用时间跨半步的交替方法,将二维活动边界分布参数控制数学模型差分化。得到三对角方程组。对电磁炮弹飞行进行数学仿真表明,该数学模型符合实际物理过程,而且控制参数不仅能有效地控制热层温度,同时能有效地控制边界活动规律。