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全身麻醉双腔支气管下电子纤维支气管镜联合肺支气管动脉栓塞介入治疗支气管扩张大咯血的临床应用研究

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中国医药指南 2024年第13期22卷 19-22页

作者：田家勇山东省临沭县人民医院重症医学科临沂276700

目的探讨全身麻醉双腔支气管下电子纤维支气管镜联合肺支气管动脉栓塞介入在支气管扩张大咯血治疗中的应用。方法按照治疗方式的不同将2019年10月至2023年10月我院收治的56例支气管扩张大咯血患者分为4组,A组实施内科保守治疗,B组实... 详细信息

目的探讨全身麻醉双腔支气管下电子纤维支气管镜联合肺支气管动脉栓塞介入在支气管扩张大咯血治疗中的应用。方法按照治疗方式的不同将2019年10月至2023年10月我院收治的56例支气管扩张大咯血患者分为4组,A组实施内科保守治疗,B组实施单纯纤维支气管镜止血治疗,C组实施单纯支气管动脉栓塞术治疗,D组则采取全身麻醉双腔支气管下电子纤维支气管镜联合肺支气管动脉栓塞介入治疗,对比四组治疗效果。结果与A、B、C组相比,D组临床总有效率较高,D组全咯血量较少、肺动脉压较低、停止血液流动时间较长、住院时间较短,D组不良反应发生率较低(P 0.05);治疗后1 h及治疗后1 d,与A、B、C组相比,D组PaO_(2)均较高,PaCO_(2)均较低(P <0.05)。结论通过采取全身麻醉双腔支气管下电子纤维支气管镜联合肺支气管动脉栓塞介入治疗支气管扩张伴大咯血患者可获得突出的综合治疗效果,患者的血气功能指标得到明显调节及改善,且操作期间并无明显不良反应,整体安全性有保证。

关键词：全身麻醉双腔支气管下电子纤维支气管镜肺支气管动脉栓塞介入支气管扩张大咯血

ACOUSTOELASTIC THEORY FOR FLUID-SATURATED POROUS MEDIA

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Acta Mechanica Solida Sinica 2014年第1期27卷 41-53页

作者： Huaqing Wang jiayong tian Institute of Crustal Dynamics China Earthquake Administration

Based on the finite deformation theory of the continuum and poroelastic theory, the aeoustoelastic theory for fluid-saturated porous media （FSPM） in natural and initial coordi- nates is developed to investigate the influence of effective stresses and fluid pore pressure on wave velocities. Firstly, the assumption of a small dynamic motion superimposed on a largely static pre- deformation of the FSPM yields natural, initial, and final configurations, whose displacements, strains, and stresses of the solid-skeleton and the fluid in an FSPM particle could be described in natural and initial coordinates, respectively. Secondly, the subtraction of initial-state equations of equilibrium from the final-state equations of motion and the introduction of non-linear constitu- rive relations of the FSPM lead to equations of motion for the small dynamic motion. Thirdly, the consideration of homogeneous pre-deformation and the plane harmonic form of the small dynamic motion gives an acoustoelastic equation, which provides analytical formulations for the relation of the fast longitudinal wave, the fast shear wave, the slow shear wave, and the slow longitudinal wave with solid-skeleton stresses and fluid pore-pressure. Lastly, an isotropic FSPM under the close-pore jacketed condition, open-pore jacketed condition, traditional unjacketed condition, and triaxial condition is taken as an example to discuss the velocities of the fast and slow shear waves propagating along the direction of one of the initial principal solid-skeleton strains. The detailed discussion shows that the wave velocities of the FSPM are usually influenced by the effective stresses and the fluid pore pressure. The fluid pore-pressure has little effect on the wave velocities of the FSPM only when the components of the applied initial principal solid-skeleton stresses or strains are equal, which is consistent with the previous experimental results.

关键词： acoustoelasticity fluid-saturated porous media wave velocity the effective stress fluid pore pressure

DYNAMIC CONTACT STIFFNESS OF VIBRATING RIGID SPHERE CONTACTING SEMI-INFINITE TRANSVERSELY ISOTROPIC VISCOELASTIC SOLID

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Acta Mechanica Solida Sinica 2008年第6期21卷 580-588页

作者： jiayong tian Zhoumin Xie Institute of Crustal Dynamics China Earthquake Administration P.O. Box 2855 Beijing 100085 China

Dynamic contact stiffness at the interface between a vibrating rigid sphere and a semi-infinite transversely isotropic viscoelastic solid is investigated. An oscillating force superimposed onto a static compressive force in the vertical direction excites the vibration of a rigid sphere, which causes variable contact radius and contact pressure distribution in the contact region. The assumption of a sufficiently small oscillating force yields a dynamic contact-pressure distribution of a constant contact radius, which gives dynamic contact stiffness at the interface between the rigid sphere and the semi-infinite solid. Numerical calculations show the influence of vibration frequency of the sphere, and elastic constants of the transversely isotropic solid on dynamic contact stiffness, which benefits quantitative evaluation of elastic constants and orientation of single hexagonal grains by resonance-frequency shifts of the oscillator in resonance ultrasound microscopy.

关键词： dynamic contact wave propagation rigid sphere transversely isotropic viscoelasticsolid

Contact vibration analysis of the functionally graded material coated half-space under a rigid spherical punch

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Applied Mathematics and Mechanics(English Edition) 2022年第8期43卷 1187-1202页

作者： Xin LYU Liaoliang KE jiayong tian Jie SU School of Mechanical Engineering Tianjin UniversityTianjin300350China National Institute of Natural Hazards Ministry of Emergency Management of ChinaBeijing100085China

This paper studies the contact vibration problem of an elastic half-space coated with functionally graded materials(FGMs)subject to a rigid spherical punch.A static force superimposing a dynamic time-harmonic force acts on the rigid spherical ***,we give the static contact problem of FGMs by a least-square fitting ***,the dynamic contact pressure is solved by employing the perturbation ***,the dynamic contact stiffness with different dynamic contact displacement conditions is derived for the FGM coated *** effects of the gradient index,coating thickness,internal friction,and punch radius on the dynamic contact stiffness factor are discussed in detail.

关键词： contact vibration functionally graded material(FGM) spherical punch perturbation method

GENERALIZED REVERBERATION MATRIX FORMULATION FOR WAVE PROPAGATION IN MULTILAYERED MEDIUM

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Acta Mechanica Solida Sinica 2010年第3期23卷 189-199页

作者： jiayong tian~★(Institute of Crustal Dynamics,China Earthquake Administration,P.O.Box 2855,Beijing 100085,China) Institute of Crustal Dynamics China Earthquake Administration Beijing China

Generalized reverberation matrix （GRM） formulation is presented to investigate elastic wave propagation in a complex multilayered solid by the combination of reverberation-ray matrix （RRM） method and stiffness matrix （SM） method. RRM method formulates a reverberation matrix, which reflects the reflection or refraction of the elastic waves in the multilayered solid. However, the dimension of RRM increases as the sublayer number increases, which may result in lower calculation efficiency of the generalized rays. SM formulation yields a system matrix of the constant dimension to promise higher calculation efficiency, but it is difficult to identify the generalized rays. In order to calculate the generalized rays in the complex multi-layered solid efficiently, the RRM formulation is applied to the interested sublayer for the evaluation of the generalized rays and SM formulation to the other sublayers, to construct a generalized reverberation matrix of the constant dimension, which is independent of the sublayer number. Numerical examples show that GRM formulation has higher calculation efficiency for the generalized rays in the complex multilayered-solid configuration compared with RRM formulation.

关键词： elastic waves multilayered medium generalized reverberation matrix stiffness matrix

SH波对界面圆柱形弹性夹杂散射及动应力集中

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爆炸与冲击 1999年第2期19卷 115-123页

作者：刘殿魁田家勇哈尔滨工程大学建筑工程系

运用Ｇｒｅｅｎ函数法求解ＳＨ波对界面圆柱形弹性夹杂的散射。首先，给出含有半圆柱形弹性夹杂的弹性半空间表面上任意一点、承受时间谐和的出平面线源荷载作用时的位移函数。其次，取该位移函数作为Ｇｒｅｅｎ函数，推导出定解积分方... 详细信息

运用Ｇｒｅｅｎ函数法求解ＳＨ波对界面圆柱形弹性夹杂的散射。首先，给出含有半圆柱形弹性夹杂的弹性半空间表面上任意一点、承受时间谐和的出平面线源荷载作用时的位移函数。其次，取该位移函数作为Ｇｒｅｅｎ函数，推导出定解积分方程。最后，给出介质参数对界面圆柱形弹性夹杂的动应力集中系数的影响。

关键词：界面圆柱形弹性夹杂 SH波散射动应力集中

有限长正交各向异性圆柱壳中瞬态轴对称弹性波的传播

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北京大学学报（自然科学版） 2000年第3期36卷 365-372页

作者：田家勇苏先樾北京大学力学与科学工程系北京100871

分析了计及剪切变形和转动惯性的有限长正交异性圆柱壳中弹性瞬态波的传播问题 ,采用回传矩阵法 ,在相空间中给出了位移和内力的表达式。再利用Laplace逆变换 ,得到正交异性圆柱壳受轴对称冲击作用时弹性瞬态波解 ,然后将其分解为若干... 详细信息

分析了计及剪切变形和转动惯性的有限长正交异性圆柱壳中弹性瞬态波的传播问题 ,采用回传矩阵法 ,在相空间中给出了位移和内力的表达式。再利用Laplace逆变换 ,得到正交异性圆柱壳受轴对称冲击作用时弹性瞬态波解 ,然后将其分解为若干广义射线积分之和 ,并用数值方法求解之。

关键词：圆柱壳正交各向异性轴对称冲击弹性瞬态波

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基于声弹理论的地应力超声测量方法

岩石力学与工程学报 2006年第z2期25卷 3719-3724页

作者：田家勇王恩福中国地震局地壳应力研究所北京100085

首先描述岩石的声弹理论,给出岩石的应力与弹性波波速之间的理论关系;其次利用岩石应力与弹性波波速之间的理论关系提出地应力超声测量方法,即通过测量套孔应力解除前后的孔壁超声波波速的变化,利用声弹理论反演出地应力。通过数值算例... 详细信息

首先描述岩石的声弹理论,给出岩石的应力与弹性波波速之间的理论关系;其次利用岩石应力与弹性波波速之间的理论关系提出地应力超声测量方法,即通过测量套孔应力解除前后的孔壁超声波波速的变化,利用声弹理论反演出地应力。通过数值算例讨论地应力对孔壁超声波速的影响,其结果表明,该方法可以有效地确定地应力的大小和方向。

关键词：岩石力学声弹理论地应力超声波波速

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岩石三阶弹性模量的高精度测定研究

岩石力学与工程学报 2010年第A02期29卷 3558-3561页

作者：田家勇满元鹏齐辉中国地震局地壳应力研究所北京100085 哈尔滨工程大学建筑工程学院黑龙江哈尔滨150001

基于岩石的声弹理论,通过脉冲回波方法测量双轴加载条件下沿薄板岩样厚度方向传播的超声纵、横波波速变化,来测定岩石的三阶弹性模量。试验结果表明:将横波和纵波传感器放置于岩样中心部位的相对表面上,测量同一地点的纵、横波波速,不... 详细信息

基于岩石的声弹理论,通过脉冲回波方法测量双轴加载条件下沿薄板岩样厚度方向传播的超声纵、横波波速变化,来测定岩石的三阶弹性模量。试验结果表明:将横波和纵波传感器放置于岩样中心部位的相对表面上,测量同一地点的纵、横波波速,不仅减弱了双向加载端部效应,而且克服了岩石的非均质性对测量结果的影响。此外,通过脉冲回波方法测量多次回波信号的时间差,来克服耦合剂和测量电路对走时差的影响。该方法可以实现岩石三阶弹性模量的高精度测定,从而为地应力测量声弹法的实现提供技术保障。

关键词：岩石力学三阶弹性模量声弹理论脉冲回波法