超混沌系统的动力学性质及同步问题的研究

选取一个超混沌Qi系统,详细分析其动力学性质。采取基于观测器的方法来实现系统在不同初值条件下的同结构投影同步,并采用反馈法的思想设计合适的控制器,以实现Qi系统和Liu系统不同结构之间的完全同步。通过Lyapunov稳定性定理证明控制器的合理性,并对两种同步方法进行数值仿真来证明其可行性和有效性。     

分数阶超混沌系统的动力学分析及同步

对一个新的超混沌系统通过分数阶线性系统稳定性理论分析得出其分数阶形式,并利用matlab仿真得出该系统的混沌吸引子图像.接着对该分数阶系统的同阶数和不同阶数两种形式进行异结构的同步分析,设计自适应同步控制器,实现该系统的异结构同步,数值仿真的结果表明设计控制器很好的实现了驱动系统和响应系统的同步.     

Donor impurity-related optical absorption coefficients and refractive index changes in a rectangular GaAs quantum dot in the presence of electric field

Within the quasi-one-dimensional effective potential model and effective mass approximation, we obtain the wavefunctions and energy eigenvalues of the ground (j=1) and first 2 excited states (j=2 and 3) of a donor impurity in a rectangular GaAs quantum dot in the presence of electric field. The donor impurity-related linear and nonlinear optical absorption as well as refractive index changes for the transitions j=1-2 and j=2-3 are investigated. The results show that the impurity position, incident optical intensity and electric field play important roles in the optical absorption coefficients and refractive index changes. We find that the impurity effect induces the blueshift for j=1-2 and redshift for j=3-2 in the absence of the electric field, but it leads to redshift for j=1-2 and blueshift for j=3-2 in the existence of the field. Also, the optical coefficient for the higher energy transitions j=2-3 is insensitive to variation of impurity positions, while that for the low energy transition j=1-2 depends significantly on the positions of impurity. In addition, the saturation and splitting phenomenon of the optical absorption are observed as the incident optical intensity increases.     

分数阶混沌系统自适应有限时间追踪控制

基于实现一类参数未知三维分数阶混沌系统有限时间追踪控制的目的,采用分数阶系统稳定性地理对分数阶Zhang混沌系统进行了动力学性质分析,采用有限时间控制法设计了一个自适应有限时间追踪控制器,通过理论计算和MATLAB数值仿真,验证了该控制器的有效性,实现了参数未知分数阶混沌系统的自适应有限时间追踪控制;在保持系统各个参数不变的情况下加入外部随机扰动,通过MATLAB数值仿真可知,该控制器具有抗干扰性.     

磁场作用下的一个含类氢施主杂质二维量子环中的电子能态

Using the finite element method, we investigate the lowest and first few excited state energies in a twodimensional GaAs quantum ring(QR) with a hydrogenic donor impurity and effective mass approximation under a uniform magnetic field perpendicular to the ring plane. We study in detail the dependence of the energy spectrum with different angular momentum on the inner radius, the outer radius and width of the QR, the magnetic field and impurity position. The results reveal that the electron energies increase with the inner radius while decrease with the outer radius and width of the QR; for a fixed ring, the magnetic field induces the increase of the electron energies. Moreover, the existence of impurity reduces energy levels, and the energy levels depend highly on the impurity position, which decreases as the impurity is far away from the center of the QR. Also, the dependence of the angular momentum on the energy spectrum is analyzed in detail.     

断裂分形理论的应用

断裂分布和结构形态具有明显的分形结构特征。详细阐述了断裂分维理论在断裂分布和结构形态方面的应用。结果表明断裂分维理论能够正确分析断裂分布特征,预测断层面的粗糙程度、断裂面结构力学性质,研究断裂的活动规律,预测油气的分布。应加强多重分维研究,对正确解决有关断裂形成、分布、断裂结构面及断裂填充物特征具有重要的意义。     

三肇凹陷T2断层分维特征及与扶杨油层油气关系

三肇凹陷扶杨油层断裂发育具有规模小、密度大且密集成带的特点,其与油气关系不清楚.为此,利用分形理论研究断裂的复杂程度,并探讨了断裂维数与油气分布的关系.扶杨油层断裂盒式维数和信息维数集中分布在1.5～1.7.维数为断裂面密度、总长度、组合模式及成因机制综合度量参数,走滑成因、部分斜拉扭动成因和伸展成因的断裂密集带维数普遍大于1.65,油气主要分布在维数为1.45～1.55的区域,表明断裂密集带不是主要的富油构造.基于断裂活动规律分析,认为成藏关键时刻明水组末期活动的断裂为油气"倒灌"运移的通道,这些断裂多为断裂密集带的边界断裂,倒灌过程中通道断层的下盘阻力小,是油气主要的分流方向,因此油气主要富集在断裂密集带边界断裂下盘河道砂中.