simple方法求不可压缩问题

下垂控制的PSCAD模型，可完美运行，供参考学习(PSCAD model droop control)

Nelder and Mead Optimization Search Method

SPECFEM2D，模拟二维各向异性粘弹性介质的地震波传播。(SPECFEM2D simulates seismic wave propagation in two-dimensional anisotropic viscoelastic or coupled viscoelastic-acoustic media.)

一篇论文，对研究转子动力学初学者有参考价值，题目为叶片振动影响下双盘转子-轴承系统的稳定性与分岔。(Paper, the study of rotor dynamics beginners reference value, titled double-disc rotor blade vibration under the influence- bearing system stability and bifurcation.)

PSCAD软件对STATCOM（静止同步无功补偿器）建模仿真例程(PSCAD software STATCOM (Static Synchronous Var Compensator) modeling and simulation routines)

ABAQUS中用户材料子程序UMAT的开发主要解决两方面的问题：本构模型的建立和积分算法的选择。 本文主要研究非线性材料的UMAT实现方法，并重点研究其迭代算法部分，目前，用户材料子程序UMAT的迭代算法主要是常刚度法，常刚度法的优点在于算法原理较简单，程序编写较方便，缺点是当遇到复杂非线性材料时，其迭代次数较多，收敛速度也较慢，在这个情况下，本文采取的是一种迭代次数较少且收敛速度较快的切线刚度法，具体就是采用FORTRAN语言编制了基于Von-Mises模型的接口程序,并采用切线刚度算法，通过与ABAQUS自带本构关系计算的结果相比较，验证其正确性。(This paper studies the user subroutine UMAT of ABAQUS development methods, the use of FORTRAN language isotropic hardening material model of the interface program, studied the effects of such material is extremely elastic-plastic constitutive relation method. This article UMAT tightly around the secondary development of technology, the first principle of its interface detail, and then for the theory of nonlinear finite element incremental stiffness of the regular tangent stiffness method and the theory of algorithms to do an in-depth analysis of deduced a regular tangent stiffness and rigidity of the law of the specific expression of algorithm theory, and then the preparation of the two algorithms, respectively, of the UMAT program, and finally the establishment of a specific model checking, bringing with ABAQUS elasto-plastic constitutive relation of the calculated results compared to verify the correctness of the two.)

说明：  1跨35米的车桥耦合程序。Fortran编写(1, 35 meters span bridge coupling procedures. Fortran write)

Abaqus UMAT code 适用于平面应变，轴对称弹塑性本构关系，也适用于大应变情况，使用显示积分算法。(Abaqus UMAT code applies to plane strain, axisymmetric elastoplastic constitutive relation, also applicable to large strain, using the integration algorithm.)

ABAQUS中各种不同本构的内聚力单元fortran用户子程序(ABAQUS in a variety of constitutive cohesive unit fortran user subroutines)

实现地震射线追踪和反演的frotran程序，适合地震勘探的同行(Seismic ray tracing implementation and inversion frotran procedures, seismic exploration for suitable peer)