反演问题

In the fourth chapter, we build the model of coefficient on one dimension partial differential equation and adopt finite element method to discrete partial differential equation and in the fifth chapter, we employ GP to identify and build the model of right-side function and adopt over-relaxation or alternating direction implicit method to solute difference equation.

在求解这些偏微分方程连续系数反演或右端连一一一~武卫1里鱼立二大一至」夔里匕崖匕位止透二立一一一一续函数的适应值评价中，我们都采用H'一范数正则化来解决连续参数的识别问题。

Because of taking only advantage of the first item in scattering series, method of Born approximation inversion is only suitable to little disturbance imaging. And it will produce great error in condition of great perturbation.

考虑到上述问题，本文在Bleistein和Cohen等人对Born近似的深入研究基础上，运用地震逆散射理论进行深度成像，反演地层奇性界面的位置。

In chapter 5 a 2D inverse technique is presented, in which the distorted Born approximation is used to speed up the convergence and the preceding INMM is employed to achieve a high speed.

第五章介绍二维低频电磁问题反演方法。为了加速收敛，采用了变形Born近似。

Its ill problem of coefficient matrix seriously restrains the vertical velocity and the others variable retrieval and stops the further development of VVP.

由此可见，VVP方法的理论构想自提出后，一直未能得到根本的实现，它的系数矩阵的病态问题严重制约了垂直速度场及其它参数的有效反演，也制约了VVP方法的进一步发展。

If directly process parameters inversion within the cross-examination variance as the objective function, we can solve this problem effectively.

如果直接以交叉检验方差为目标函数进行参数反演，则可以有效地解决这个问题。

In offshore oil and gas field development, the number of wells drilled, the application of seismic data play an important role in gas field management, especially for the problems of lateral changes of reservoir physical properties and the distribution of remaining oil, which are hard to be solved by using conventional hydrocarbon detection and wave impendence inversion at the late stage of gas field development.

在海上开发的油气田中，由于钻井数量，地震资料的应用在气田的管理中具有非常重要的作用，特别是在气田开发的中后期，常规的烃类检测技术和波阻抗反演技术已经无法解决储层物性横行变化的问题和剩余气分布的问题。

This article focuses on research of prediction of rock-burst happened in Cangling extreme long-tunnel engineering, comparison of tunnel carving details in the performing stage and prevention measures.

通过对苍岭特长隧道岩爆问题的预测研究和施工阶段洞身开挖情况对比，以及针对本工程的岩爆防治措施研究，探讨了岩爆预测判据对苍岭隧道工程的适用性，揭示了苍岭隧道围岩的岩性特征和初始应力场，掌握了苍岭隧道岩爆发生的烈度和基本分布规律，提出了对岩爆问题的工程防治措施，另外，根据工程区地质条件和岩石物理力学性能参数，建立了相应的地质力学模型，采用有限元法建模反演分析，其结果与通过钻孔水压致裂试验测得的地应力结果比较，显得较为吻合，并得到施工阶段通过洞壁应力恢复法分析结果的验证，验证表明理论模型和有限元模型的适用性及分析应力场是较为准确和合理的，并在此基础上对苍岭隧道岩爆进行分段预测和采取了较有成效的工程防治措施，具有较高的工程应用价值。

Employment of a neural network in LAI reversions can improve such issues to a certain extent, but the ill-posed nature for canopy reflectance model inversion is yet to be resolved.

神经网络算法的介入可在一定程度上改善这一问题，但是模型反演的病态问题至今仍无法很好地解决。

Three-layer tissues model, which is consisted of thin skin, fat and the semi-infinite muscle, is adopted.

该方法为一种有效的正问题计算方法，可直接应用于需要利用二次磁场信息反演有耗媒质分布的正问题计算。

The Xujiahe formation in south Sichuan basin is featured by continental clastic sedimentary, thin sand mud interbed, and the welldeveloped sandstone in this area, however, its lithology is tight and its physical properties is poor. In the case of gas bearing, the acoustic velocity difference between the sandstone and the shale is too little to make clear responses on seismic data, as a result, it is very difficult to conduct the gasbearing prediction and to analyze the gasbearing range distribution by means of conventional impedance inversion and hydrocarbon detection.

四川盆地蜀南地区上三叠统须家河组为一套砂泥岩互层的陆相碎屑岩沉积，砂岩发育，但岩性致密，物性较差，砂岩储层含气后的速度与页岩速度相差不大，在地震剖面上无明显的响应，因而采用常规波阻抗反演和含气检测技术不能有效解决该类含气储层识别问题和含气范围展布问题。

Chrysanthemum of 10 thousand birthday is lax to edaphic requirement, with the arenaceous qualitative loam with fecund, good drainage had better.

万寿菊对土壤要求不严，以肥沃。排水良好的砂质壤土为好。

He unstepped the mast and furled the sail and tied it.

他拔下桅杆，把帆卷起，系住。