西宁市林家崖滑坡稳定性研究

林家崖滑坡是一个具有上下两个滑体的滑坡系统，本文首先阐述其特性，对其变形控制因素及机理进行分析研究，并将常规Sarma法和基于Sarma法的基本原理的一种新的计算公式结合起来对该滑坡系统的稳定性进行了分析研究。指出，对于这种双层滑体滑坡，在进行稳定性分析时应视情况而增加考虑上滑体滑动效应，以使结果更合理，为滑坡治理设计提供更科学的依据。     

非轴对称陀螺体自激运动的定性分析

研究非轴对称陀螺体在自激控制力矩作用下的姿态运动．将无力矩状态的两个初积分的积分常数T和G^2作为描述自激运动的状态变量建立其微分方程．利用受扰运动在(T，G^2)空间中的相轨迹判断稳态运动的稳定性，并进行了数值验证．     

刚性椭球对固定面的三维摩擦碰撞

讨论刚性椭球对固定面的三维摩擦碰撞．以法向冲量为自变量，建立碰撞过程中接触点切向速度的微分方程．利用相平面的奇点理论对碰撞过程中切向滑动的全局性态作定性分析，并导出切向滑动的解析积分．     

运用Matlab的线性供应链仿真控制策略研究

由于供应链终端需求的不确定性,需求信息在向上级传递过程中逐渐放大,容易造成"牛鞭效应".通过分析线性供应链的系统特征,并研究其稳定性的条件,并运用不同的策略,对其进行仿真模拟,结果表明:综合考虑近邻、次近邻的库存需求和终端消费者的需求变化时各供应商的库存波动得到明显的改善.在仿真模拟结果中,最大库存波动值是2.48,且考虑终端消费者的权重是0.248时,波动消失,说明最大库存波动值对终端消费者的敏感性较强,结果表明改进后的策略能抑制牛鞭效应对供应商库存波动的影响.     

全二维气相色谱-质谱法定性分析土壤中有机氯农药、酞酸酯和多氯联苯

建立了土壤中20种有机氯农药、16种酞酸酯和18种多氯联苯的全二维气相色谱-质谱分离和定性方法。土壤样品与无水Na2SO4(1:1,m/m)混匀后,用丙酮、正己烷(1:1,V/V)在微波快速溶剂萃取仪上以1600W的功率,在20 min内从室温升至110℃,并保持20 min的条件进行萃取。通过优化升温速率、调制周期及热喷时间等参数,该方法能够在40.5 min内分离目标化合物及土壤萃取杂质,并通过二维谱图和质谱检索对54种目标化合物准确定性。     

Stability analyses of the mass abrasive projectile high-speed penetrating into concrete target. Part Ⅰ： Engineering model for the mass loss and nose-blunting of ogive-nosed projectiles

The mass loss and nose blunting of a projectile during high-speed deep penetration into concrete target may cause structural destruction and ballistic trajectory instability of the penetrator,obviously reducing the penetration efficiency of penetrator.Provided that the work of friction between projectile and target is totally transformed into the heat to melt penetrator material at its nose surface,an engineering model is established for the mass loss and nose-blunting of the ogive-nosed projectile.A dimensionless formula for the relative mass loss of projectile is obtained by introducing the dimensionless impact function I and geometry function N of the projectile.The critical value V c0of the initial striking velocity is formulated,and the mass loss of projectile tends to increase weakly nonlinearly with I/N when V0〉V c0,whilst the mass loss is proportional to the initial kinetic energy of projectile when V0     

Fokas方程的显示孤立尖波解和周期尖波解

利用一个独立变换和动力系统方法对Fokas方程:u_(tx)=(1+v(?)■_x~2)sin(u),x∈R,t0进行研究.在对该方程所对应的平面动力系统进行定性分析的基础上,得到了该方程所有可能的显式孤立尖波解和周期尖波解.     

未知控制方向的简单线性对象间接自适应跟踪系统的稳定性分析（英文）

本文研究一类一阶线性连续时间对象的自适应跟踪器,并给出不同估计量和修正确定性等价控制律.我们克服了确定损失的困难(或控制)的系统增益的估计值是零,纠正了米德尔顿和Kokotovic的文章(1992)对上述对象的间接自适应调节的一些实质性的错误的结果.在构建的自适应跟踪系统中,得到相平面轨迹或完全描述闭环系统的非线性行为的显式解的显式表达式,并对所设计的自适应跟踪系统可能由损失估计模型的稳定性所带来问题进行分析.讨论了这些结果对高阶线性连续时间对象的间接自适应跟踪情况的影响.同时通过类似的模式讨论了未知的控制方向和模型参数.     

Stabilization of optical solitons in chirped PT-symmetric lattices

We investigate the stability properties of optical solitons in a chirped PT-symmetric lattice whose frequency changes in the transverse direction. Linear-stability analysis together with the direct propagation simulations demonstrates that the chirped lattice can improve the stability of optical solitons dramatically. The instability of fundamental solitons can be completely suppressed if the chirp rate exceeds a critical value. A broad stability area of dipole solitons appears if the lattice is appropriately chirped. Thus, we propose an effective way to suppress the instability of solitons in PT-symmetric potentials.     

A Lattice Hydrodynamic Model for Traffic Flow Accounting for Driver Anticipation Effect of the Next-Nearest-Neighbor Site

In this paper, a new lattice hydrodynamic model is proposed by incorporating the driver anticipation effect of next-nearest-neighbor site. The linear stability analysis and nonlinear analysis show that the driver anticipation effect of next-nearest-neighbor site can enlarge the stable area of traffic flow. The space can be divided into three regions： stab/e, metastable, and unstable. Numerical simulation further illuminates that the driver anticipation effect of the next-neaxest-neighbor site can stabilize tramc flow in our modified lattice model, which is consistent with the analytical results.