:弹性波在孔洞上的散射问题可采用复变函数方法求解,用含有待定系数的"域函数"表示散射波的位移势函数,如何准确地求解该待定系数是获得问题解答的关键.本文根据孔洞边缘的径向和切向应力为零的边界条件用最小二乘法建立求解待定系数的线性方程组,得到有限项系数的近似解.通过圆孔、椭圆孔和方孔的数值算例,分析了P波作用下不同形状孔洞边缘的动应力集中系数的特征,讨论了孔边的径向和切向应力计算误差与待定系数项数的关系.计算结果表明,采用最小二乘法求解散射波的待定系数,能够获得满足一定精度要求的孔附近动应力集中系数的解答.

Complex function and general conformal mapping methods are used to investigate the scattering of elastic shear waves by an elliptical cylindrical cavity in a radially inhomogeneous medium.The conformal mappings are introduced to solve scattering by an arbitrary cavity for the Helmholtz equation with variable coefficient through the transformed standard Helmholtz equation with a circular cavity.The medium density depends on the distance from the origin with a power-law variation and the shear elastic modulus is constant.The complex-value displacements and stresses of the inhomogeneous medium are explicitly obtained and the distributions of the dynamic stress for the case of an elliptical cavity are discussed.The accuracy of the present approach is verified by comparing the present solution results with the available published data.Numerical results demonstrate that the wave number,inhomogeneous parameters and different values of aspect ratio have significant influence on the dynamic stress concentration factors around the elliptical cavity.

采用波函数展开法给出了具有圆柱型正交各向异性半圆形沉积谷地形对SH波散射的解答,研究了入射波特性和沉积谷的各向异性对地面运动的影响.稳态SH波入射时,在圆柱型正交各向异性沉积谷中波函数的径向函数满足非整数阶的Bessel方程.数值结果表明:沉积谷地表位移的幅值大小与入射波的频率、入射方向、沉积谷介质的径向与环向剪切模量比及半空间与沉积谷剪切波速比和密度比密切相关,当沉积谷介质比半空间介质软时,沉积谷地表位移幅值明显增大,与各向同性介质的沉积谷地相比,沉积谷介质的各向异性对地面运动的影响非常显著.

The dynamic stress concentration on quadratic and U-shaped cavities in half space, which are similar to the cross-section of the tunnels, is solved in this paper impacted by SH-wave. The analytical solution for the cavity in elastic half space is gained by the complex function method. In the complex plane, the scattering wave which satisfies the zero-stress condition at the horizontal surface can be constructed, the problem can be inverted into a set of algebraic equations to solve coefficients of the constructed scattering wave by least square method. For the earthquake-resistance researches, the numerical examples of the dynamic stress concentration around the quadratic and U-shaped cavities impacted by SH-wave are given. The influences of the dynamic stress concentration by the incident wave number and angle, the depth and shape of the cavity are discussed. It is showed that the interaction among the wave, the surface and the shallow buried tunnels should be cared in half space. In this situation, the dynamic stress concentration around the tunnel is greater obvious than the whole space.

Summary form only given. In general, analytical solution for the scattering problem of SH plane wave by a cavity in half-space primarily focused on the circular structure case. However, the case for U-shaped cavities, which are similar to the cross-section of the tunnels, was seldom mentioned in former references. The analytical solution for U-shaped cavity in elastic half space is gained by the multi-polar coordinate system and conformal mapping method. A scattering wave function satisfying zero-stress condition on horizontal surface is constructed in the complex plane, the problem can be inverted into a set of algebraic equations to solve coefficients of the scattering wave by least square method. The numerical examples of the dynamic stress concentration around U-shaped cavities and ground motion on subsurface U-shaped cavity impacted by SH-wave are given. The influences of the incident wave number, angle and depth are discussed. The research indicates that the shallow U-shaped tunnel has significant impact on wave propagation, and interaction between the U-shaped tunnel and the horizontal surface will complicate characteristics of ground motion, and will bring about great increase on dynamic stress around cavity. In this situation, enough attention should be paid on the interaction between the subsurface cavity and the horizontal surface in the seismic design of ground and underground structures.

随着抗甲状腺药物和碘剂的临床应用,甲状腺切除术后发生甲状腺危象已极其少见,而非甲状腺手术术后并发甲亢危象更是罕见.本院收治2例急腹症患者术后并发甲亢危象,经及时诊治痊愈,现报告如下.

例1,患者，男，45岁，因上腹部疼痛2 h，加剧1 h抬送入院。诊断为弥漫性腹膜炎，胃十二指肠溃疡并穿孔。入院查体：T 36.8 ℃，P 100次/分，BP 110/70 mmHg，腹平坦，板状腹，全腹压痛、反跳痛。腹部平片提示膈下新月形游离气体。完善术前准备，急诊行胃大部分切除术。术中患者出现高热、燥烦不安，心率120～140次/分，大汗淋漓，甚至谵妄。予以胃肠减压，积极抗炎及对症治疗，上述症状持续加重。追问患者有甲亢病史，查T3 2.97 ng/ml,T4 133.5 ng/ml,FT3 17.18 pmol/L,FT4 66.30 pmol/L。考虑为甲状腺功能亢进(甲亢)危象，予以：(1)Lugol溶液2 ml＋生理盐水20 ml灌肠，每天1次；(2)丙基硫氧嘧啶300 mg灌肠，每天1次；(3)心得安10 mg舌下含服，每4 h 1次； (4)利血平1 mg