查询词典 boundary element method

In quasi-static conditions, the closed expressions far from source in the air and the earth is derived for electric dipole source, and by using it as the outer boundary conditions of the finite element method, difficulties in loading the boundary conditions is solved.

在准静态近似条件下，分别推导了水平电偶极子在空中和大地的远区电场闭合表达式，并以此作为有限元计算中的外边界条件，解决了边界条件加载的困难。

The governing equation is the mild-slope equation. Finite element method has advantage to treat complicated boundary. The second order radiation boundary condition is expanded to improve the wave model for large incident wave angles. The validity of the second order radiation condition is examined through varying arbitrary wave incident angles.

模式将以包含波浪绕射及反射之缓坡方程式建立数值模式，利用有限元素法易於处理不规则边界的优点，引用二阶近似辐射边界条件，扩展波场模式处理大角度波浪入射的能力，探讨在未碎波的情形下，二阶辐射边界条件对於任意角度波浪入射之适用情形。

Heat conduction equation ; Galerkin boundary element method ; Indirect boundary integral equation ; Simple layer potential2000 MSC:35F99; 35K05; 80M15

热传导方程； Galerkin边界元法；间接边界积分方程；单层位势

The gap element method is proposed in the paper for two kinds of problems, which include contact problem and gap joint problem. Elasticity contact problem falls into the category of unknown boundary value problems. It follows that the contact area and contact conditions or states can never be determined without special mathematical analysis, which is a very difficult work. The boundary conditions of the contact surfaces are deduced.

文中给出了间隙元法在空间可动部件接触问题中的应用，推导了其几何边界条件和力学边界条件，利用虚功原理推导了含间隙元弹性接触问题的有限元方程式，给出了其数值解法的迭代步骤，并指出了利用间隙单元进行分析的特点。

Boundary element method for pressure calculation of arbitrary shape and mixed boundary reservoir

以任意形状二维均质油藏的定解问题为基本的数学模型，推导了实空间和拉氏空间中的边界元数值计算方法。

Firstly it describes the development ,basic principle and application and propagation characteristic of mobile channel , then investigates the system structure of DAB transmitter and receiver separately and the key technology of realization of the digital audio broadcast system.And then discusses the system component of FFT －the demodulation module of OFDM .The 409- points FFT module employs a radix-4 decimation-in-frequency algorithm, includes arithmetic element , read and write address element ,twiddle factor element and control element , is realized by FPGA. In the end , the result is verified in the matlab .

首先概述了OFDM的发展、基本原理和应用以及移动信道的传播特性，接着分别研究了数字音频广播接收机和发射机的系统结构，以及数字音频广播系统实现的关键技术，然后详细论述了OFDM解调模块FFT的系统结构，主要研究了4096点FFT采用基－4按频率抽取实现的算法，整个FFT模块包括了运算单元、读写地址单元、旋转因子单元以及控制单元，并且在FPGA中进行了硬件实现，并在matlab环境下对结果进行了验证。

The invention also discloses a system of searching path, the said system is composed of an establishing element of auxiliary chart and arithmetic element. The said establishing element of auxiliary chart is used to establish an auxiliary chart for reflecting all the usable link resource in network and established path pair of minimum cost. The said arithmetic element is used to search a path for satisfying the reliability constraint in the auxiliary chart after receiving the service connection request.

本发明还公开了一种寻找路径的系统，该系统包括辅助图建立单元和运算单元：所述辅助图建立单元用于建立反映了网络中所有能够使用链路资源及能够建立的最小代价路径对的辅助图；所述运算单元用于在收到业务连接请求后，在所述辅助图建立单元建立的辅助图中寻找到满足可靠度约束的路径。

The results indicate that the effect of alloying elements V and Cr on mechanical properties at room-temperature, creep behavior and microstructures are similar. With increasing contents of V and Cr, their mechanical properties produce little change, the creep resistant property decreases and microstructure grows, which is mainly due to their characteristics of β-stability element and smaller atomic radius compared with Ti. On the contrary, the effects of V and Cr on the thermal stability are quite different. With increasing V content or decreasing Cr content the thermal stability for the alloy becomes better, which may be due to the different solution characteristics of V and Cr element in titanium alloy that V belongs to isomorphous β-stability element and Cr belongs to eutectoid β-stability element.

结果表明：合金元素V和Cr对Ti40合金室温力学性能、蠕变行为和组织的影响具有相似性，即随V和Cr含量的降低，合金室温综合力学性能变化不明显、抗蠕变能力减弱、组织粗化：这与V和Cr同属于β稳定元素、且原子半径都小于Ti原子有关；而V和Cr对于热稳定性能的影响则完全相反，V含量的增加或Cr含量的降低含金热稳定性能优化，其主要原因可能与V属于同品型β稳定元素而Cr属于共析型β稳定元素有关。

The blood pressure of.1 of pathology physiology mechanism that SAS causes CVD breathes time-out to be able to bring about airframe in elevatory Morpheus anoxic, sympathetic is excessive and excited, element of serous catechu phenolic amine, kidney and hemal endodermis element are elevatory, bring about hemal easy of hemal convulsion; to shrink the function is disorder, can make blood-vessel flowing flesh happening reframes and fleshy, systemic blood-vessel obstruction adds element of the kidney when; is chronic and anoxic, system of hemal and nervous element is activationed, bring about blood pressure to lift. Obstruction of way of energy of life of patient of OSAS of disease of blood of 1.2 low oxygen increases, cause air current to interrupt, breath pauses, at the same time airframe gets used to low oxygen environment gradually, breathing centre drops to low oxygen and sensitivity of disease of blood of tall carbonic acid, breath suspends a frequency increasing, farther aggravating airframe is anoxic. 1.3 heads are self-adjusting the function drops normal person changes quickly in systematic circulation blood pressure when, the head can be passed adjust independently functional generation protects effect, make change of cerebral blood flow not big.

SAS诱发CVD的病理生理机制。1血压升高睡眠中呼吸暂停可导致机体缺氧，交感神经过度兴奋，血浆儿茶酚胺、肾素以及血管内皮素升高，导致血管痉挛；血管舒缩功能紊乱，可使血管平滑肌发生重构和肥厚，全身血管阻力增加；慢性缺氧时肾素—血管紧张素系统被激活，导致血压升高。1.2低氧血症OSAS患者气道阻力增加，造成气流中断、呼吸暂停，同时机体逐渐适应低氧环境，呼吸中枢对低氧和高碳酸血症敏感性下降，呼吸暂停次数增加，进一步加重机体缺氧。1.3脑自动调节功能下降正常人在体循环血压快速变化时，脑可通过自主调节功能产生保护效应，使脑血流量变化不大。

Based on the shell element degraded from the continuous body, concrete and configured steels are modeled by the layered shell element, and the vertical steels burdened with added loads are completed by the combined shell element. Then, with the smeared crack model, associated flow rule and Madrid hardening model, the material nonlinearity of the concrete is depicted. The stiffness matrix of nonlinear thin-walled shell element is deduced. As for RC multi-T girders subjected to transverse loads, the properties, such as crack expanding and steel yielding, are studied.

基于实体退化壳单元理论，采用分层单元模拟了混凝土和构造钢筋，采用组合单元模拟了受力纵筋；并利用弥散裂缝模型、关联流动法则和Madrid强化准则等来描述了混凝土的材料非线性，推导了非线性薄壁壳单元的统一单元模式，研究了横向荷载作用下RC多T梁上部结构的裂缝发展和钢筋屈服等性能。

The statistical analysis of this large set of mutations has led us to propose a diagnostic strategy that should help with the molecular work-up of optic neuropathies.

这一大系列基因突变的统计学分析引导我们提出一个诊断策略，可以帮助我们对视神经病变进行分子学的诊断检查。

The results show that the pipe grouting changes the mechanical parameters of surrounding rocks to achieve the security of engineering objectives by reinforcing surrounding rocks and bolcking the water.

研究表明：小导管注浆一方面改变了围岩的力学参数，另一方面利用浆液的固结特性可以实现堵水和加固围岩的工程目标，使隧道在开挖过程中的安全得到保障。