Space time-index plots for probing dynamical nonstationarity

We propose a simple method to efficiently probe dynamical nonstationarity in observed time series. In a space time-index plot, the density distributions as a function of normalized time-index are V-shaped due to nonstationarity. We show that this method is workable for short data sets and typical examples are illustrated.     

两个不等式的加强与证明

本文利用幂平均加强了林同坡不等式和Ｓｔｏｌａｒｓｋｙ不等式，并给出了证明．     

Concerning the multiplicators of Fourier series in the trigonometric system

In this paper we prove theorems on multiplicators of Fourier series inL _p, where the conditions depend on a parameterp. An example illustrating the importance of these conditions is constructed. Translated fromMatematicheskie Zametki, Vol. 63, No. 2, pp. 235–247, February, 1998.     

高功率飞秒脉冲激光器的进展

概述了超短激光脉冲技术发展的历程。详尽的论述了啁啾脉冲放大技术的原理和一些关键技术 ,并对当今飞秒激光器研究发展的状况进行了综述。在分析其应用前景的基础上 ,进一步指出了这一技术领域未来的发展趋势。结果表明 ,脉冲激光放大系统以后的发展方向是 :更短脉冲 ;追求更高峰值功率 ;连续光谱调谐化 ;向小型化乃至全光纤化发展。     

高功率横流CO2激光器脉冲预电离过程研究

本文给出了对高功率横流CO_2激光器脉冲预电离过程的理论和实验研究.表明了预电离过程中光电离的重要作用.实验结果表明,脉冲预电离可增大高功率横流CO_2.激光器的pd值(p为放电气压、d为放电间隔),增大放电区注入功率密度.对于提高此类型激光器的放电稳定性和输出激光功率是一种技术简单而有效的手段.     

磁控溅射技术制备ZnO透光薄膜

采用RF磁控溅射方法,在玻璃衬底上制备了择优取向的ZnO薄膜;通过台阶仪、X射线衍射技术、原子力显微镜和分光光度计分别测量了不同溅射功率条件下淀积的ZnO薄膜厚度(淀积速率)、结晶质量、表面形貌与粗糙度、透光光谱,报道了该薄膜结晶质量、薄膜粗糙度与其在可见光区透光率的关系.     

p+209Bi核反应微观数据的理论计算

利用光学模型、激光模型、蒸发模型及扭曲波玻恩近似理论,对入射能量从阈能到300MeV,p+²⁰⁹Bi的中子反应截面、剩余核截面、出射粒子的多重数进行了理论计算及分析,并将计算结果与实验数据进行了比较.同时得到一组能量到50?0MeV与实验数据符合很好的光学势参数.     

Long-term optimal operation of series parallel reservoirs for critical period with specified monthly generation and average monthly storage

We present in this paper an efficient approach for solving the problem of planning the long-term (multiyear) operation of a multireservoir hydroelectric power system for the critical period with a monthly variable load. This load is equal to a certain percentage of the total generation at the end of the year, subject to satisfying a number of constraints on the hydrosystem, using the minimum norm formulation.The proposed method is efficient in computing time and in calculating the total expected benefits from the system during the critical period. Numerical results are reported for a real system in operation consisting of two rivers. Each river has two series reservoirs.This work was supported by the Natural Science and Engineering Research Council of Canada, Grant No. A4146.     

平面上随机级数的性质

研究了平面上系数{Xn,n≥0}为(?)-混合序列在满足,(q>1)等条件下的随机级数的增长性及值分布,得到了比较好的结果．     

高功率微波高斯馈源口面场分析

 用波导本征模展开方法对用于高功率微波发射系统的方角锥高斯馈源口面场进行分析，提出结合馈源远场辐射特性和避免高功率击穿折衷选定相应的高斯模注腰半径，进而确定多个波导模幅值，从而为运用模匹配或耦合波理论设计高斯馈源提供依据。