数值方程

The stability of numerical methods for the linear Volterra delay integro differential equation was studied. A sufficient condition such that the implicit block θ-methods preserved the delay-independent stability of its exact solutions was obtained.

研究了线性中立型Volterra延迟积分微分方程数值方法的稳定性，给出了块隐式θ-方法保持系统解析解不依赖于延迟的稳定性质的一个充分条件。

The numerical calculation and influencing factors of casing well resistivity logging are studied.The response equation of resistivity logging is established based on the electromagnetic field theory and the distribution characteristics of the electric field in the intermediate zone.

根据电磁场理论和中场区电场分布特点，建立套管井地层电阻率测井测井响应方程，用传输线理论分析了套管井测井数值计算的可行性，分析了水泥环、地层电阻率、套管厚度等因素对测井响应的影响。

The asymptote behavior of intermediate point in the Mean Value Theorem for integrals ;2. Based on numerical integrals , the model parameters are estimated from the differential equation without iterations, the method is very effective in overcoming large amounts of measurement noise in the output.

提出一种简单但鲁棒性强的传感器动态建模方法，该方法基于数值积分思想，能有效克服测量噪声，无需迭代即可直接从微分方程辨识出模型参数，所建模型阶次较低、准确度较高，且较易实现递推算法，为传感器改善动态特性、实现动态补偿提供一种有效方法。

The main results of the study are obtained as follows:1 In order to analyze and study the physical and mechanical characteristics of Lianyungang marine soft clay deeply, large numbers of basic mechanical characteristics tests and tri-axial shear tests are completed.2 In order to investigate the loaded and failure characteristics of the cement-soil, the cement-soils for the different ratio and different cure time are studied in the laboratory, and their unconfined compression tests and tri-axial shear tests are performed.3 Based on the solution of one-dimension consolidation, the one-dimension consolidation of the double-layered foundation is solved for two-grade loading in virtue of transcendental equation; Simultaneously, the one-dimension consolidation of the double-layered foundation is solved by means of Laplace transform for two-grade loading, and Stehfest numerical transform is applied in Laplace's inverse transformation; Furthermore, according to the practical foundation shapes, the consolidation models of the soil between piles and the substratum are built and solved respectively.4 The effect of each parameters on the consolidation of the double-layered foundation is discussed, and the solution of load transfer method for double-layered foundation is applied in A1-A4 section of Lian-Xu expressway. The results of calculating settlement of the double-layered consolidation theory are basic agreement with the measuring settlement results.

取得了以下几方面的研究成果：1针对连云港海相软土进行一维固结和三轴剪切试验，深入分析连云港海相软土的物理力学特性。2模拟水泥土搅拌桩施工，在室内制备不同配比、不同龄期的水泥土试样，并进行无侧限抗压试验和三轴剪切试验，揭示水泥土的受力特性及破坏特性。3运用超越方程，以双层地基一维固结解析解为基础，推导出二级加荷条件下双层地基的固结解析解；同时，通过荷载传递法并借助Laplace变换对双层地基的固结问题进行了数值求解；此外，根据实际的地基结构，建立了桩间土和下卧层的固结模型并分别进行求解分析。4分析探讨了双层地基中各参数对双层地基固结的影响程度，并运用荷载传递法的解答计算了连-徐高速公路A1-A4标水泥土搅拌桩处理段的六个断面，计算结果与实测数据有较好的一致性。

Inverse M-matrices often occur in relation to systems of linear or non-linear equations or eigenvalues problems in a wide variety of areas including finite difference methods for partial differential equations, input-output production and growth model in economics, iterative methods in numerical analysis, and Markov processes in probability and statistics.

其中包括偏微分方程的有限差分法、经济中的投入产出和增长模型、数值分析中的迭代法以及概率论和数理统计中的马尔可夫过程。

Most of the current finite element software packages treat it using the net-radiation method or absorbed radiation method based on the assumption of isothermal surface with uniform radiation heat flux,which brings the conflict between the precision and the quantity of grids.

进行了选用高阶单元、采用高斯积分精确计算单元表面变辐射热流方法的研究，从而摆脱了一致表面温度和辐射热流的假设，使得在相同网格密度的情况下计算精度大大提高；同时，从包含辐射换热问题的有限元计算方程出发，采用与有限元数值计算时相同的积分方案，只在独立的积分点处计算辐射热流，克服了积分方法计算效率低的缺点。

The forward finite difference and Newton iterance are used in the light of box model and other heavy gas dispersion models, such as IIT Heavy Gas Models and virtual point source model, to solve the differential equations of controlling heavy gas cl.

文中从控制重气云团扩散行为的微分方程入手，根据箱模型及其他一些重气扩散模型，如IITHeavyGasModels模型和虚点源模型，采用向前插分和牛顿迭代的方法，针对ThorneyIslandTrialNo 。0 0 8试验进行了数值模拟，得到了重气云团外形尺寸和空气卷吸量随时间的变化关系以及下风向固定点处地面最大浓度值。

It is necessary to analyze the convergence of a special class of such step- parallel iteration methods for delay differential equations.

针对延迟微分方程分析了一类特殊的并行迭代法的收敛性，数值算例表明这种算法是有效的。

Simulation of PN junction diode lays the foundation for the simulations of other semiconductor elements.

本文结合非耦合数值方法，通过求解半导体方程对PN结二极管进行模拟分析，得到了一些重要物理参量分布，这为深入研究电磁辐射对半导体元件的干扰奠定了基础。

Preliminary numerical results for the Laplace equation and Navier system are presented, and tricky issues associated with these methods, such as the ill-conditioning with the interpolation matrix and effect of shape parameter, are investigated.

文中给出了Laplace方程和Navier方程组的数值结果，考察了插值矩阵的病态性以及径向基函数中形参数的影响。

For a big chunk of credit-card losses; the number of filings (and thus charge-off rates) would be rising again, whether

年美国个人破产法的一个改动使得破产登记急速下降，而后引起了信用卡大规模的亏损。

Eph. 4:23 And that you be renewed in the spirit of your mind

弗四23 而在你们心思的灵里得以更新