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1.
1.IntroductionInthispaperweshallconsideradiscontinuousnonlinearnonmonotoneellipticboundaryvalueproblem,i.e.aquasilinearelliptichemivariationalinequalitywhereAn=--Z:=,hat(x,u,7u) ac(x,usac)an4thesymbolaldesignatesclarke'sgeneralizedgradientofalocallyL...  相似文献   

2.
This paper presents some recent works on the control of dynamic systems,which have certain complex properties caused by singularity of the nonlinear structures,structure~varyings, or evolution process etc. First, we consider the structure singularity of nonlinear control systems. It was revealed that the focus of researches on nonlinear control theory is shifting from regular systems to singular systems. The singularity of nonlinear systems causes certain complexity. Secondly, the switched systems are considered. For such systems the complexity is caused by the structure varying. We show that the switched systems have significant characteristics of complex systems. Finally, we investigate the evolution systems. The evolution structure makes complexity, and itself is a proper model for complex systems.  相似文献   

3.
研究了具有常量速度强化因子的两相流动模型,证明了在忽略弥散效应的情况下模型将导致不适定问题,提出如果不考虑任何滞后效应常量速度强化因子将导致聚合物油波前沿上的聚合物聚集.对于IPV(InaccessiblePoreVolume)速度强化效应建立了渗滤模型,该模型中的速度强化因子是水相饱和度的函数,所对应的偏微分方程系统不存在椭圆区域的完全双曲型系统,它不存在常量速度强化因子所固有的稳定性问题.  相似文献   

4.
研究生产计划和控制中带交货期约束且子任务之间具有先序关系的资源选择问题,证明了该问题是NP完全问题,目前该问题还没有多项式时间求解算法.建立了该问题的非线性整数规划模型,分析了模型中目标函数和约束函数的单调性,并根据该单调性构造了分支定界求解算法.与招投标算法比较,表明分支定界算法具有求解问题的规模大、运算速度快的优越性.  相似文献   

5.
1 Formulation of Dirichlet Problem and Neumann Problem fOrParabolic SystemsLet O be a bounded domain in Rn and the boundary On E C2. Denote Q = g x I,I =0 < t 5 T, 0 < T < ool 0Q = Sl U S2 is the parabolic boundary where S1 = a x {t = 0} is thebottom and S2 = an x I is the lateral boundary. We consider the nonlinear parabolic systemof second order equationsFh(t, xl ut D.u, D:u) -- Hukt = 0 in Q, k = 1, 2,'',m. (l.l)Under certain conditions, system (1.1) can be reduced to the fOrmw…  相似文献   

6.
Nonlinear constrained optimization problem(NCOP) has been arisen in a diverse range of sciences such as portfolio, economic management, airspace engineering and intelligence system etc.In this paper, a new multiobjective imperialist competitive algorithm for solving NCOP is proposed.First, we review some existing excellent algorithms for solving NOCP; then, the nonlinear constrained optimization problem is transformed into a biobjective optimization problem. Second, in order to improve the diversity of evolution country swarm, and help the evolution country swarm to approach or land into the feasible region of the search space, three kinds of different methods of colony moving toward their relevant imperialist are given. Thirdly, the new operator for exchanging position of the imperialist and colony is given similar as a recombination operator in genetic algorithm to enrich the exploration and exploitation abilities of the proposed algorithm. Fourth, a local search method is also presented in order to accelerate the convergence speed. At last, the new approach is tested on thirteen well-known NP-hard nonlinear constrained optimization functions, and the experiment evidences suggest that the proposed method is robust, efficient, and generic when solving nonlinear constrained optimization problem. Compared with some other state-of-the-art algorithms, the proposed algorithm has remarkable advantages in terms of the best, mean, and worst objective function value and the standard deviations.  相似文献   

7.
1.IntroductionTheconceptsofrelativedegreeandzerodynamicshavebeenproposedbyByrnes,Isidoriandotherstotreatlocalfeedbackstabilizationproblemofnonlinearcolltrolsystems.Oneofthekeypointsforthismethodistousecelltermanifoldtheory.[1]wasoneoftheearliestworksusingcentermanifoldtechniqueinthisarea.Firstofall,wewilldescribethecentermanifoldmethodthroughanexampletoshowhowthecentermanifoldmethodcanbeusedtosolvethestabilizationproblem.Forconvenience,wecitesomebasicresultsfrom[2].Theorem1.1Considerasystemw…  相似文献   

8.
针对非线性滤波组合导航中四元数无迹估计器(unscented quaternion estimator, USQUE)规范性约束导致的算法计算量大、实时性差等问题, 提出一种基于双欧拉角姿态表示的无迹卡尔曼滤波(dual-Euler unscented Kalman filter, DEUKF)算法。通过正、反欧拉角相互切换, 在正、反欧拉微分方程精华区进行姿态滤波更新, 避免了奇异性, 确保了滤波精度。捷联惯性导航系统/全球定位系统直接式组合导航仿真试验与车载实验结果表明, 相比较于USQUE算法, DEUKF算法计算量小、实时性好, 水平姿态角估计精度与USQUE相当。  相似文献   

9.
基于核函数变换的PLS非线性回归模型既吸取了核函数能够拟合适应任意连续变化曲线的优点,又借鉴了偏最小二乘回归方法能够有效解决自变量集合高度相关的技术。在本文中针对多元加法模型,从理论和仿真试验的角度分别验证了,对于多个独立自变量对单因变量为非线性关系的数据系统,基于核函数变换的PLS回归方法不仅能够有效实现自变量对因变量的整体预测,而且能够提取各雏自变量对因变量的单独非线性作用特征,从而确定数据系统内部的复杂非线性结构关系,增强了模型的可解释性。  相似文献   

10.
A finite-time tracking control scheme is proposed in this paper based on the terminal slid- ing mode principle for motor servo systems with unknown nonlinear dead-zone inputs. By using the differential mean value theorem, the dead-zone is represented as a time-varying system and thus the inverse compensation approach is avoided. Then, an indirect terminal sliding mode control (ITSMC) is developed to guarantee the finite-time convergence of the tracking error and to overcome the singu- larity problem in the traditional terminal sliding mode control. In the proposed controller design, the unknown nonlinearity of the system is approximated by a simple sigmoid neural network, and the ap- proximation error is diminished by employing a robust term. Comparative experiments on a turntable servo system are conducted to show the superior performance of the proposed method.  相似文献   

11.
1.TheirregularObliqueDerivativeProblemanditsWell-PosednessforNonlinearEllipticSystemsLabDbean(N 1)-connectedboundeddomaininthez=x ic-planeCwithboundaryFECI(0相似文献   

12.
Target tracking using distributed sensor network is in general a challenging problem because it always needs to deal with real-time processing of noisy information. In this paper the problem of using nonlinear sensors such as distance and direction sensors for estimating a moving target is studied. The problem is formulated as a prudent design of nonlinear filters for a linear system subject to noisy nonlinear measurements and partially unknown input, which is generated by an exogenous system. In the worst case where the input is completely unknown, the exogenous dynamics is reduced to the random walk model. It can be shown that the nonlinear filter will have optimal convergence if the number of the sensors are large enough and the convergence rate will be highly improved if the sensors are deployed appropriately. This actually raises an interesting issue on active sensing: how to optimally move the sensors if they are considered as mobile multi-agent systems? Finally, a simulation example is given to illustrate and validate the construction of our filter.  相似文献   

13.
模糊基函数网络学习算法及其应用   总被引:1,自引:0,他引:1  
本文在文献[1]的基础上提出了模糊基函数网络(FBFN)改进的学习算法。改进的正交最小方差算法(MOLS)解决了原算法逼近多维函数的性能很差的问题,并且提高了该算法实际的逼近性能和收敛性。最后给出了FBFN应用于雷达数据关联的实验结果。  相似文献   

14.
具有建设成本的占线中心选址问题及其竞争算法设计   总被引:1,自引:1,他引:0  
研究待选址个数不确定的动态选址问题. 在实际选址过程中,经常会在全部需要建立的设施个数未知的前提下,决定在哪里建立初始的设施(或设施集),同时要求,当增加建立设施时,已经建立的设施不能被删除.此外,基于实际,待建立的设施间的初始建设成本是不同的. 建立了满足上述约束的占线选址动态模型,并给出一个竞争算法,最后证明该算法具有常数的竞争比.  相似文献   

15.
CONTINUATIONMETHODOFNONLINEARINTEGRALEQUATIONS¥YANGFenghang;SUNJing(DepartmentofMathematics,TianjinUniversity,Tianiin300072,C...  相似文献   

16.
In references,some authors have succeeded in obtaining existence re-sults of the superlinear wave equation without the assumption of monotonicity forthe nonlinear term.In this paper,we present existence results for this problem byusing local linking idea and improve some previous results.  相似文献   

17.
采用混合单亲遗传算法求解一类资源-时间优化问题   总被引:5,自引:0,他引:5  
针对资源有限最短时间的一类资源 -时间优化问题 ,提出了混合单亲遗传算法进行求解 .作为一类 NP完全问题 ,该问题求解难度相当大 ,尤其问题规模大时寻找最短时间优化解就更困难 .针对问题的特点本文引入的算法结合了启发式规则 ,给出了算法全局收敛的理论分析 ,并给出实际应用表明该算法的有效性.  相似文献   

18.
在商户广告投资内生化和双边平台特性下,建立两阶段动态博弈模型,研究网上交易平台的最优定价及利润.研究表明:1)平台定价策略受广告效果和平台固有效果两种作用的影响.广告效果相对平台固有效果较小时,商户实力(与投资预算有关)的相对差距较小,平台定价策略倾向于让所有商户都加入;广告效果相对较大时,平台会根据商户实力的相对差距制定定价策略,差距越小(大),平台希望吸引的商户就越多(少).2)商户价格敏感性较高时,平台定价较低,利润较小.商户外部性较大时,平台应吸引更多的商户.特别地,广告效果相对较小时,商户外部性越大,平台定价越高.  相似文献   

19.
一种新的基于神经网络的非线性组合预测方法   总被引:18,自引:0,他引:18  
一种新的基于神经网络的非线性组合预测方法文新辉牛明洁(西安电子科技大学,710071)(新疆石油学院,乌鲁木齐830000)ANewNonlinearCombinedForecastingMethodontheBasisofNeuralNetwork...  相似文献   

20.
1 IntroductionThis paper presents a quasi-Newton method in infinite-dimensional spaces for identifyingparameters involved in a time-variant continuous, nonlinear system of differential equations.It is well known that quasi-Newton methods are considered to be those of the most success-ful algorithms used for numerically solving optimization problems in finite-dimensional spaces.But, few papers discuss these methods in system identification research. Because many iden-tification problems can be…  相似文献   

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