Exact Analytical Solutions of Static Electroelastic and Thermoelectroelastic Problems for a Transversely Isotropic Body in Curvilinear Coordinate Systems

An approach to the solution of three-dimensional static problems for a transversely isotropic (rectilinear anisotropy) body is expounded and the solutions for piezoceramic canonical bodies are systematized. The result of the study is explicit analytical solutions of three-dimensional problems. Bodies are examined whose boundary surface is the coordinate surfaces in coordinate systems that permit the separation of the variables in the three-dimensional Laplace equation. The stress concentration in bodies near necks, cavities, inclusions, and cracks is investigated. The stress intensity factors of the force field and electric induction near elliptic and parabolic cracks are determined. The contact interaction of a piezoceramic half-space with elliptic and parabolic dies is studied. The bodies are under various mechanical, thermal, and electric loads     

高阶退化Bernoulli数和多项式

本文研究了高阶退化Berrioulli数和多项式的两个显明公式，得到了一个包含高阶Bemoulli数和Stirling数的恒等式，并推广了F．H．Howard，S．Shirai和K．I．Sato的结果。     

剩余寿命增补变量法在排队模型M/GI/1/K中的应用

本文尝试用剩余寿命作为增补变量，建立了经典排队模型M／GI／1／K的密度演化方程，并应用递归的方法得到了模型队长平稳分布的精确解．     

关于开尔文表述和克劳修斯表述的等价性的一点讨论

讨论了热力学第二定律的开尔文表述和克劳修斯表述的等价性的一个问题     

Improving simple explicit methods for unsteady open channel and river flow

A rigorous study of the explicit Lax–Friedrichs scheme for its application to one‐dimensional shallow water flows is presented. The deficiencies of this method are identified and the way to overcome them are presented. It is compared to the explicit first order upwind scheme and to the explicit second order Lax–Wendroff scheme by means of the simulation of several test cases with exact solution. All three schemes in their best balanced version are applied to the simulation of a real river flood wave leading to very satisfactory results. Copyright © 2004 John Wiley & Sons, Ltd.     

一类专家意见的不确定性量化法与不确定性决策

以不确定性信息的数学处理理论为基础,建立了一类专家意见的不确定性量化表达式,定义了表达式间的运算与运算律,给出此类专家意见合成的不确定性决策模型.     

n级梯形电阻网络的研究

介绍了n级梯形电阻网络的等效电阻计算方法，并得到其具体表示公式。     

一类带双指标常系数齐次递推关系的显式解

本文推广了屠规彰＾［１］的结果，得到了一类带双指标的常系数齐次递推关系的一个明显解公式。有关结果，不论是在理论还是在实际方面，都有一定的意义。     

重组tPA及其突变体纤溶活性的比较

将重组基因rtPA及其突变体rtPAm分别克隆到原核表达载体pET his上,通过平板筛选,双酶切和PCR鉴定获得阳性克隆子,重组质粒转化大肠杆菌BL21(DE3).经IPTG诱导,表达出的两种tPA蛋白都形成不可溶的包涵体.SDS PAGE结果显示两种tPA蛋白分子量为4.0×104左右,表达产量较高.包涵体经尿素变性,透析复性后柱层析纯化,纤溶平板法测定激活纤溶蛋白酶的活性,结果显示rtPAm比活性比rtPA高70%左右.     

黑曲霉脂肪酶基因的克隆及其在毕赤酵母中的表达

根据黑曲霉F044脂肪酶N-端氨基酸序列，运用生物信息学方法，找到与黑曲霉脂肪酶基因同源的候选基因A84689．根据该基因序列，设计引物直接经RT—PCR扩增得到黑曲霉脂肪酶全长基因anl．anl全长1044bp，含3个内含子，编码297个氨基酸（含信号肽27个氨基酸），与其他脂肪酶基因没有明显的同源性．将成熟脂肪酶基因连接到pPIC9K载体上得到重组表达质粒，转化P．pastoris GSll5．脂肪酶基因在P．pastoris GSll5中实现了分泌性表达．