首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 125 毫秒
1.
研究一类竞争一合作生态数学模型平衡点的渐近稳定性,得到了保证该系统平衡点是渐近稳定的一组充分条件.  相似文献   

2.
研究一类竞争—合作生态数学模型平衡点的渐近稳定性,得到了保证该系统平衡点是渐近稳定的一组充分条件.  相似文献   

3.
同步发电机数学模型是电力系统稳定性分析的关键。结合电力系统稳定性分析需求,建立了用于电力系统稳定性分析的同步发电机数学模型,论述了用于电力系统稳定性分析的同步发电机数学模型的应用内容与要点,以期为电力系统稳定性分析提供参考。  相似文献   

4.
建立了一个由流域、湖泊和引水工程组成的非线性水资源控制系统。运用水量平衡原理建立了系统的数学模型。通过构建Lyapunov函数估计了该系统控制变量的临界值,讨论了系统的稳定性。  相似文献   

5.
针对数学模型是两个方程的非线性常微分方程组,讨论一种多层离散的格式及其稳定性条件,从而由此格式计算该方程组的数值近似解.  相似文献   

6.
基于Matlab的电力系统暂态稳定仿真实验与分析   总被引:2,自引:0,他引:2  
提出了适用于时域仿真的数学模型。对实例进行分析,考虑单机无穷大系统和三机系统,使用Matlab编程求解所得的数学模型,仿真暂态过程中发电机转子摇摆曲线,从而判定电力系统的暂态稳定性。单机系统的仿真结果表明:发电机阻尼越大,故障切除时间越短,系统越容易稳定;三相短路故障时系统最容易失稳。多机系统的仿真结果表明:Tj越大,达到稳定所需的时间越长;当KV满足静态稳定要求时,KV越大,系统的暂态稳定性越好。对于多机系统,讨论了重合闸对暂态稳定的影响。该方法丰富了Matlab在电力系统暂态稳定方面的应用。  相似文献   

7.
针对变化风场尤其是大气紊流严重影响无人机飞行安全的问题,通过构建大气紊流数学模型并分析其对飞行的影响,为非线性无人机建立了六自由度模型,设计了一种模糊自整定PID控制器并进行了Matlab仿真。仿真结果表明,该控制器可提高无人机在变化风场中的稳定性和稳态精度。  相似文献   

8.
陈冬玲 《柳州师专学报》2015,(2):125-127,135
针对干熄焦提升机定位系统具有多变量及存在随机电磁干扰的特点,通过采用RBF神经网络学习算法,实时在线辨识,建立被控对象的精确数学模型并用于控制,实现了当定位系统受强电磁干扰时,系统仍然能够保障提升机正常运行.应用结果表明,该智能控制系统既保证了干熄焦提升机定位系统的稳定性,又提高了对工况电磁干扰的适应性.  相似文献   

9.
主要利用了构造Lyapunov函数的方法探讨一类浮游生物数学模型的正周期解的渐近稳定性的一些充分条件。  相似文献   

10.
本文主要针对常微分方程组类型的生态数学模型,应用常微分方程稳定性理论作出稳定性分析,主要使用李雅普诺夫第二方法讨论多种群落的全局稳定性。  相似文献   

11.
基于Matlab仿真软件,考虑弹性水击对水轮机调节系统的影响,建立弹性水击水轮机微分代数模型,并与调速器和发电机共同构成水轮机调节系统非线性模型。在此基础上运用非线性动力学分叉理论对PID调速器参数进行Hopf分叉行为研究,得出PID参数三维分叉曲面、二维分叉曲线及稳定域,并通过对时域图、相轨迹图等的综合分析,得到取不同调速器参数时系统的非线性动力学特性,为机组PID参数选择提供理论依据。最后通过系统仿真得出,在小扰动下线性模型和非线性模型均能适用,在大扰动下非线性模型能更真实地反映机组动态特性。  相似文献   

12.
本文对网络控制系统中网络诱导时延问题进行了讨论,建立了时延网络控制系统的模型,采用混杂系统的理论分析了系统的稳定性,提出了网络诱导时延的补偿方法。  相似文献   

13.
分析了谐振传感系统的稳定性条件,并根据稳定性误差得到了稳定性能指标。在理论的基础上,对谐振传感系统作了具体设计,得到了以振子的振动速度作为输出以稳定系统的频率的设计思想,以及增加AGC环节以稳定振幅并获得较理想的正弦波的设计思想。建立了振子电磁耦合模型,并对整个系统进行了仿真,验证了所作设计的正确性。  相似文献   

14.
基于麦克斯威尔方程,给出导电薄板的非线性磁弹性振动方程,以及磁场环境下的电动力学方程和电磁力表达式。在此基础上,应用伽辽金法导出相应的非线性振动微分方程组,研究横向恒定磁场中周期载荷作用下梁式薄板的稳定性问题。根据李雅普诺夫近似稳定性理论,对稳态解的稳定性进行分析,得到稳定性的判定条件。通过对算例特征值的求解对振动的稳定性进行分析。  相似文献   

15.
一种实时模拟血管中引导线变形的有限元模型   总被引:1,自引:0,他引:1  
为了实时仿真微创介入手术过程中引导线在外力作用下的变形,提出了一种适合于描述纤细物体力学特性的模型.通过对引导线的仿真,医生可以在术前预演手术,并选择最佳的手术方案.模型采用多体结构离散化引导线,根据弹性理论推导出引导线的弹性能是节点位移的多项式函数,病人的血管四面体网格模型可从血管的三角面网格模型拓广得到,并将共轭梯度法能量下降的过程应用于引导线变形过程的模拟.实验结果表明:由于模型的弹性能和节点位移呈多项式函数关系,共轭梯度法的求解得到了有效的简化,模型的效率有显著提高.与目前广泛采用的显式计算模型相比不仅稳定且更快速.模型可应用于血管中引导线变形的实时仿真.  相似文献   

16.
Updated Bayesian detection of foundation parameters in the specific foundation mechanical model was studied based on Jeeves pattern search theory. Firstly, the updated Bayesian objective function for general foundation parameters was derived which could synchronously take the stochastic property of systematic parameters and systematic responses into account. Then the governing differential equations for the Winkler foundation model were gained with elastic Mindlin plate theory and the Fourier close form solution of the foundation model was achieved with the Fourier transform method. After the step length of pattern movement was determined with the quadratic parabolic interpolation method, the updated Bayesian detection of stochastic foundation parameters was resolved with Jeeves pattern search theory and then the corresponding detection procedure was completed. Through particular example analysis, the updated Bayesian detection of stochastic foundation parameters has excellent numerical stability and convergence during iterative processes. Jeeves pattern search theory is unconcerned with the partial derivatives of systematic responses to foundation parameters, and undoubtedly has satisfactory iterative efficiency compared with the available Kalman filtering or conjugate gradient detections of the significant foundation parameters. If the iterative processes are efficiently convergent, it is an important prerequisite that the systematic response assignment should be accurate enough. The derived Jeeves pattern search method with updated Bayesian theory can be applied in other kinds of foundation parameters.  相似文献   

17.
The space effects of deep pit slope are analyzed by an elastic mechanics principle. The interaction among the critical slide angle, the friction coefficient, the cohesion, and the horizontal radius of the deep pits is derived in this paper. It indicates that the deeper the pit is excavated, the greater the critical slide angle is. Both the theory for reducing stripping waste rock in deep pit and the approach to determining the configuration of the stable slope are developed from the interaction. The theory in this paper comprises the preceding principles of stability analysis of slopes and is suitable for analyzing that of deep pit.  相似文献   

18.
The ‘student voice’ is highly profiled in UK higher education, yet highly under-theorised. Over the past 20 years UK universities have gone from a taxpayer-funded, free at the point of use model, to one supported through tuition fees via Government-backed loans. Subsequently, there is a growth of discourse about universities as businesses and students as paying customers/consumers whose opinions and demands must be considered. This article outlines four possible theoretical lenses (or frameworks) through which student voice can be analysed, enabling an exploration of the vested interests and power relations entailed. These lenses draw on (1) research on student voice and power in compulsory education; (2) regulatory capture from Economics; (3) the notion of students voice as part of an incomplete whole and (4) non-representational theory, developed in Human Geography by Nigel Thrift.  相似文献   

19.
河洛文化是中华民族的核心文化,是中华文化的源头。中华民族的多元及文化的多元无不昭示祖先文化的强健与活力。河洛文化的兼容性,表现为内在的阳刚与形态的阴柔、多元的灵魂、文化与政治联袂以及随地生根的活力。本文拟从她的兼容性特征入手,分析其兼容性的基石、形态、表现与途径,为实现祖国统一及现代化进行学理性分析。  相似文献   

20.
To investigate the cage stability of high-speed oil-lubricated angular contact ball bearings, a dynamic model of cages is developed on the basis of Gupta’s and Meeks’ work. The model can simulate the cage motion under oil lubrication with all six degrees of freedom. Particularly, the model introduces oil-film damping and hysteresis damping, and deals with the collision contact as imperfect elastic contact. In addition, the effects of inner ring rotational speed, the ratio of pocket clearance to guiding clearance and applied load on the cage stability are investigated by simulating the cage motion with the model. The results can provide a theoretical basis for the design of ball bearing parameters.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号