共查询到20条相似文献，搜索用时 976 毫秒
1.
P.N. Paraskevopoulos 《Journal of The Franklin Institute》1979,308(5):475-486
This paper considers the problem of matching the transfer function matrix of a given two-dimensional (2-D) system to that of a desired 2-D model using state feedback. The approach followed refers to systems having square transfer function matrices and reduces the problem to that of solving a linear system of equations. Furthermore, necessary and sufficient conditions are established for exact matching. An example is included to illustrate the proposed method. 相似文献
2.
R. Padma Sree 《Journal of The Franklin Institute》2006,343(2):152-160
The method of identifying first order plus time delay transfer function model proposed for unstable systems by Ananth and Chidambaram [Closed loop identification to transfer function model for unstable systems, J. Franklin Inst. 336 (1999) 1055-1061] is modified to avoid the stability problems [Cheres, Parameter estimation of an unstable system with a PID controller in a closed loop configuration, J. Franklin Inst., 2005, accepted for publication] of the method. Two modifications are proposed. In the first modification of the method, the under-determined algebraic equations problem is converted into an optimization problem for calculation of the three parameters of the first order plus time delay (FOPTD) model. A simple method is given for the initial guess values of the model parameters. In the second approach, from the definition of Laplace transform of the output response, a third equation is formulated. The resulted three equations, in terms of the three parameters of the transfer function model, are then numerically solved. Simulation results are given for the second order plus time delay transfer function considered by Cheres 2005 [Parameter estimation of an unstable system with a PID controller in a closed loop configuration, J. Franklin Inst., 2005, accepted for publication]. The responses of the identified models with the same PID controllers are compared with that of the actual system. PID controllers are designed based on the identified models. The closed loop responses of the controllers on the original system are evaluated and compared. The present methods give better control performances. 相似文献
3.
4.
《Journal of The Franklin Institute》2022,359(11):5272-5287
In the 3-D path planning, the undulation of terrain have a significant impact on the roll angle of autonomous vehicle (AV). However, the existing 3-D path planning methods rarely consider the roll angle, which may lead to the rollover of AV. To solve this problem, a 3-D path planning system considering the rollover and path length (3DPPS-CRPL) is presented in this work. The 3DPPS-CRPL can plan a shorter path on the basis of inhibiting the roll angle of AV. In order to inhibit the roll angle, a novel roll angle evaluation model based on the undulation of terrain is developed, and the amount of computation is also greatly reduced because complex dynamics is avoided. In order to optimize the path length, both 2-D and 3-D path length are evaluated synthetically by a path length evaluation model. In order to optimize the parameters of 3DPPS-CRPL, a fuzzy-based optimizer is proposed to determine the weight of roll angle and path length. The simulation results prove that 3DPPS-CRPL has excellent performance for inhibiting roll angle and optimizing the path length in 3-D environment. 相似文献
5.
This paper investigates the problem of sliding mode control (SMC) for discrete-time two-dimensional (2-D) systems subject to external disturbances. Given a 2-D Fornasini–Marchesini (FM) local state space model, attention is focused on designing the 2-D sliding surface and sliding mode controller, which guarantees the resultant closed-loop system to be asymptotically stable. Particularly, this problem is solved using the model transformation based method. First of all, sufficient conditions are formulated for the existence of a linear sliding surface guaranteeing the asymptotic stability of the equivalent sliding mode dynamics. Based on this, a sliding mode controller is synthesized to ensure that the associated 2-D FM system satisfies the reaching condition. The efficiency of the proposed 2-D SMC law design is shown by a numerical example. This paper extends the idea of model transformation to the 2-D systems and solves the SMC problem of a more general 2-D model in FM type for the first time. 相似文献
6.
Ayd?n K?z?lkaya 《Journal of The Franklin Institute》2005,342(1):39-67
In this paper, the problem of estimating the parameters of a two-dimensional autoregressive moving-average (2-D ARMA) model driven by an unobservable input noise is addressed. In order to solve this problem, the relation between the parameters of a 2-D ARMA model and their 2-D equivalent autoregressive (EAR) model parameters is investigated. Based on this relation, a new algorithm is proposed for determining the 2-D ARMA model parameters from the coefficients of the 2-D EAR model. This algorithm is a three-step approach. In the first step, the parameters of the 2-D EAR model that is approximately equivalent to the 2-D ARMA model are estimated by applying 2-D modified Yule-Walker (MYW) equation to the process under consideration. Then, the moving-average parameters of the 2-D ARMA model are obtained solving the linear equation set constituted by using the EAR coefficients acquired in the first step. Finally, the autoregressive parameters of the 2-D ARMA model are found by exploiting the values obtained in first and second steps. The performance of the proposed algorithm is compared with other 2-D ARMA parameter and spectral estimation algorithms available in the technical literature by means of three different criteria. As a result of this comparison, it is shown that the parameters and the corresponding power spectrums estimated by using the proposed algorithm are converged to the original parameters and the original power spectrums, respectively. 相似文献
7.
研究了一种基于正面人脸照片的真实感三维人脸自动重建方法,并运用计算机视觉图OpenCV和图形开发库OpenGL ,在VC＋＋6．0环境下开发了三维人脸自动建模系统。该系统对输入的人脸照片首先进行人脸检测,在检测到的区域进行人脸关键特征提取,并根据检测到的特征点的几何信息对CANDIDE-3模型进行整体和局部调整,得到个性化的三维几何人脸,最后从人脸图像上获取面部纹理信息并得到真实感的三维人脸。 相似文献
8.
《Journal of The Franklin Institute》1987,323(3):373-383
Two techniques are developed for approximating a given three-dimensional (3-D) digital filter by a 3-D rational function. The one is by a general 3-D rational function and the other by a 3-D rational function which is separable in the denominator. Each technique relies on the use of mixed first and second information, in the form of a finite portion of the impulse response and its autocorrelation sequence. The approximation is performed by solving a set of linear equations. The separable-denominator approximation is more advantageous due to the guaranteed stability and reduced amount of calculations. 相似文献
9.
The problem of designing a linear state feedback controller for single-input single-output decoupling of linear multivariable 2-D (two-dimensional) systems is discussed. A method is presented for the determination of the decoupling controller matrices which, when applied to the open-loop system, yield a closed-loop system whose transfer function matrix is diagonal and nonsingular. Necessary and sufficient conditions are established for the state feedback decoupling problem to have a solution. Two examples are included to illustrate the proposed decoupling method. 相似文献
10.
11.
Imran Ghous Zhaoxia Duan Jahanzeb Akhtar Muhammad Jawad 《Journal of The Franklin Institute》2019,356(16):9407-9431
This paper aims to solve the problem of sliding mode control for an uncertain two-dimensional (2-D) systems with states having time-varying delays. The uncertainties in the system dynamics are constituted of mismatched uncertain parameters and the unknown nonlinear bounded function. The proposed problem utilizes the model transformation approach. By segregating the proper Lyapunov–Krasovskii functional in concert with the improved version of Wirtinger-based summation inequality, sufficient solvability conditions for the existence of linear switching surfaces have been put forward, which ensure the asymptotical stability of the reduced-order equivalent sliding mode dynamics. Then, we solve the controller synthesis problem by extending the recently proposed reaching law to 2-D systems, whose proportional part is appropriately scaled by the factor that does not depend on some constant terms but rather on current switching surface’s value, which in turn ensures the faster convergence and better robustness against uncertainties. Finally, the proposed results have been validated through an implementation to a suitable physical system. 相似文献
12.
丘陵山区地块尺度耕地社会保障功能价值研究 总被引：8，自引：0，他引：8
在构思地块尺度耕地社会保障功能价值测算方法,测算调查水田、旱地地块社会保障功能价值的基础上,识别耕地社会保障功能价值影响机理,构建促进耕地社会保障功能价值供需平衡的综合措施体系.结果表明:①水田地块的社会保障功能价值水平总体高于旱地地块,耕地地块复种指数越高、经济作物种植比例越高,越利于耕地地块社会保障功能作用的发挥;②耕地地块社会保障功能价值受到农户家庭人均耕地面积和农户家庭农业人口人均非农纯收入因子的显著负影响,受到耕地地块地均纯收益因子的显著正影响;③要促进耕地社会保障功能供需平衡,一要通过增加耕地资源数量和提高耕地资源的物质产品产出能力来提升耕地资源的社会保障功能供给能力,二要从提高农户家庭的非农收入水平、加快农村人口向城镇转移、进一步加强农村社会保障体系的建设与完善来减弱人类对耕地资源社会保障功能的依赖程度. 相似文献
13.
Delay-dependent guaranteed cost control for uncertain 2-D discrete systems with state delay in the FM second model 总被引：1，自引：0，他引：1
This paper is concerned with the problem of delay-dependent guaranteed cost control for uncertain two-dimensional (2-D) state delay systems described by the Fornasini and Marchesini (FM) second state-space model. Given a scalar α∈(0,1), a sufficient condition for the existence of delay-dependent guaranteed cost controllers is given in terms of a linear matrix inequality (LMI) based on a summation inequality for 2-D discrete systems. A convex optimization problem is proposed to design a state feedback controller stabilizing the 2-D state delay system as well as achieving the least guaranteed cost for the resulting closed-loop system. Finally, the simulation example of thermal processes is given to illustrate the effectiveness of the proposed result. 相似文献
14.
本文提出基于典型相关分析的国家重大工程科技资源配置行为测度模型,对科技资源配置行为的投入产出边际弹性进行敏感性分析,并以"奥运科技(2008)行动计划"支持的项目数据库中能源环保类分数据库项目数据进行实证分析,结果表明投入指标中科技人力资源的边际弹性远高于科研经费和研发时间的边际弹性,产出指标中报告的边际弹性为负,投入的三个原始变量对于产出指标中论文的边际弹性优于其他指标,并给出相应的建议分别是应注重建立科技供给与需求及时、有效对接的、以政府为主导的多部门联合的组织协调机制,高度重视国际学术交流与合作,以及通过激励和约束机制,引导科研人员发表高水平和高质量的科研论文。 相似文献
15.
16.
《Journal of The Franklin Institute》2021,358(15):7413-7425
This paper deals with the problem of stabilization via synchronous state-feedback control for two-dimensional (2-D) discrete-time Roesser systems with stochastic parameters involving switchings and multiplicative stochastic noises. The switching process is driven by an inhomogeneous Markov chain whose transition probability matrix is piecewise time-invariant and external disturbances are of the type of white noises, which get multiplied into both system state and input vectors. Stability and tractable controller design conditions are derived based on a 2-D mode-dependent Lyapunov function approach, which are validated by a numerical example with simulations. 相似文献
17.
Zhaowen Xu Hongye Su Renquan Lu Zheng-Guang Wu 《Journal of The Franklin Institute》2017,354(14):6234-6246
This paper investigates the non-fragile dissipative filtering problem for a class of two-dimensional (2-D) switched systems. Based on the well-known Roesser model, a 2-D switched system is considered. A stochastic process subject to a so-called sojourn probability is utilized as the switching rule. The non-fragile concept is introduced to design the filter in which the additive gain variation is assumed to occur randomly. Sufficient conditions for the existence of a desired dissipative filter are presented and the design scheme is given by convex optimization techniques. A numerical example is provided to show the effectiveness and the superiority of the proposed new design technique. 相似文献
18.
This paper studies the two-dimensional (2-D) expected power bound (EPB) for 2-D digital filters with multiplicative noise in the Fornasini-Marchesini local state-space (FMLSS) model. By virtue of a class of linear matrix inequalities (LMIs), the novel existence criterion of 2-D EPB for 2-D digital filters in the considered model is obtained. The corresponding stabilization controller design method is presented based on the above criterion. Finally, two examples are presented to verify the effectiveness of our results. 相似文献
19.
20.
The use of lower-order models in obtaining approximate solutions in optimal control problems has been of much interest during the past few years. Two new procedures for order reduction, based on interpreting the system impulse response (or transfer function) as an input–output map, are presented. The relationship between the states of the original system and the states of its reduced-order model is investigated. The lower-order model is used to obtain suboptimal controllers in linear regulator problems. Several computational examples are given. 相似文献