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Sound Transmission Loss Analysis of a Double Plate-Acoustic Cavity Coupling System with In-Plane Functionally Graded Materials
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作者 Changzhong Chen Mingfei Chen Wenliang Yu 《Journal of Applied Mathematics and Physics》 2024年第6期2333-2345,共13页
In this paper, the isogeometric analysis (IGA) is employed to develop an acoustic radiation model for a double plate-acoustic cavity coupling system, with a focus on analyzing the sound transmission loss (STL). The fu... In this paper, the isogeometric analysis (IGA) is employed to develop an acoustic radiation model for a double plate-acoustic cavity coupling system, with a focus on analyzing the sound transmission loss (STL). The functionally graded (FG) plate exhibits a different material properties in-plane, and the power-law rule is adopted as the governing principle for material mixing. To validate the harmonic response and demonstrate the accuracy and convergence of the isogeometric modeling, ANASYS is utilized to compare with numerical examples. A plane wave serves as the acoustic excitation, and the Rayleigh integral is applied to discretize the radiated plate. The STL results are compared with the literature, confirming the reliability of the coupling system. Finally, the investigation is conducted to study impact of cavity depth and power-law parameter on the STL. 展开更多
关键词 Isogeometric Analysis Sound Transmission Loss Double-Plate system functionally Graded Materials Acoustic Structure Coupling
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Functional Confirmation Using a Medical X-Ray System of a Semiconductor Survey Meter
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作者 Katsunao Suzuki Toru Negishi +2 位作者 Yoh Kato Yasuhisa Kono Michiharu Sekimoto 《Open Journal of Radiology》 2024年第1期1-13,共13页
In recent years, semiconductor survey meters have been developed and are in increasing demand worldwide. This study determined if it is possible to use the X-ray system installed in each medical facility to calculate ... In recent years, semiconductor survey meters have been developed and are in increasing demand worldwide. This study determined if it is possible to use the X-ray system installed in each medical facility to calculate the time constant of a semiconductor survey meter and confirm the meter’s function. An additional filter was attached to the medical X-ray system to satisfy the standards of N-60 to N-120, more copper plates were added as needed, and the first and second half-value layers were calculated to enable comparisons of the facility’s X-ray system quality with the N-60 to N-120 quality values. Next, we used a medical X-ray system to measure the leakage dose and calculate the time constant of the survey meter. The functionality of the meter was then checked and compared with the energy characteristics of the meter. The experimental results showed that it was possible to use a medical X-ray system to reproduce the N-60 to N-120 radiation quality values and to calculate the time constant from the measured results, assuming actual leakage dosimetry for that radiation quality. We also found that the calibration factor was equivalent to that of the energy characteristics of the survey meter. 展开更多
关键词 Semiconductor Survey Meter functional Confirmation Medical X-Ray system Calibration Factor Time Constant
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基于自由曲面和L-system的红掌生长模型
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作者 邹一波 褚诗贤 +1 位作者 葛艳 陈明 《湖南农业大学学报(自然科学版)》 CAS CSCD 北大核心 2024年第1期85-90,共6页
针对红掌花卉生长可视化中参数难以确定的问题进行研究,提出推导控制点的方法,建立红掌器官模型:采用Bezier曲线结合扫描成型的方法来构造叶柄模型,采用双三次NURBS曲线对佛焰苞进行建模;运用红掌的相关表型数据拟合生长函数,提出基于... 针对红掌花卉生长可视化中参数难以确定的问题进行研究,提出推导控制点的方法,建立红掌器官模型:采用Bezier曲线结合扫描成型的方法来构造叶柄模型,采用双三次NURBS曲线对佛焰苞进行建模;运用红掌的相关表型数据拟合生长函数,提出基于红掌生长规律的微分L-system,可有效模拟红掌的拓扑结构和生长过程;通过虚拟器官表示红掌器官的几何属性,降低微分L-system的复杂度。试验验证提出的方法对红掌各项生长指标拟合度可达0.89以上,并可对每个生长阶段的红掌进行模拟,能有效地对红掌的生长过程进行建模。 展开更多
关键词 红掌 自由曲面建模 L-system 生长函数 虚拟器官
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Nutritional Support under the Neuman Systems Model for Stroke Patients
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作者 Meifen Lv Jinyue Jiang +7 位作者 Luoqiong Lei Yuhua Gui Qiongfang Hu Fang Ye Lijuan Lu Hong Yang Na Yan Shiying Zhang 《Open Journal of Nursing》 2024年第7期329-343,共15页
Objective: To explore nutritional support under the Neuman systems model in treating dysphagia in stroke patients. Methods: In this retrospective study, we enrolled 97 patients with dysphagia after stroke admitted to ... Objective: To explore nutritional support under the Neuman systems model in treating dysphagia in stroke patients. Methods: In this retrospective study, we enrolled 97 patients with dysphagia after stroke admitted to our hospital, and randomly divided them into the Neuman group (n = 51) given nursing intervention based on Neuman systems model and a control group (n = 46) given routine nursing intervention. Both groups received nutritional support for 3 months. Nutritional indexes (serum total protein, plasma albumin, serum albumin, hemoglobin and transferrin levels) and immune indexes (immunoglobulin (Ig) A, IgG, IgM and total lymphocyte count (TLC) in both groups were recorded and compared. Pulmonary function recovery, video fluoroscopic swallowing study score, water swallowing test score, complication rate, and health knowledge mastery level were also compared between the two groups. Results: After the intervention, the Neuman group showed less decrease in the nutritional and immune index scores (serum total protein, plasma albumin, hemoglobin, serum albumin;IgA, IgG, IgM, and TLC;all P Conclusion: For patients with stroke and dysphagia, comprehensive nursing intervention (e.g., nutritional support) under theNeuman systems model can promote the recovery of immune, swallowing, and pulmonary function, reduce complication incidence and facilitate comprehensive rehabilitation, ensuring adequate nutritional intake. 展开更多
关键词 STROKE DYSPHAGIA Neuman systems Model Nutritional Support Pulmonary function
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Systemic-Functional Grammar and English Extensive Reading
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作者 陈小敏 《海外英语》 2011年第12X期37-38,共2页
Systemic Functional Linguistics is known to people by its special functionalism and social meaning. The study of Systemic Functional Linguistics is also accepted by more and more people. In addition, it means a lot to... Systemic Functional Linguistics is known to people by its special functionalism and social meaning. The study of Systemic Functional Linguistics is also accepted by more and more people. In addition, it means a lot to the learning of lexis, English writing and extensive reading. 展开更多
关键词 systemic-functional GRAMMAR ENGLISH learning EXTENSIVE READING
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Application of Systemic-Functional Grammar in Reading Teaching
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作者 巩茗珠 《疯狂英语(理论版)》 2016年第4期45-46,49,共3页
Based on M.A.K.Halliday's systemic-functional grammar,the paper puts forward some ideas on how to develop reading skills,analyzing how the ideational,interpersonal and textual functions are reflected and their int... Based on M.A.K.Halliday's systemic-functional grammar,the paper puts forward some ideas on how to develop reading skills,analyzing how the ideational,interpersonal and textual functions are reflected and their interrelationship in reading materials,with an attempt to improve the reading ability. 展开更多
关键词 systemic-functional GRAMMAR Reading skills
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The Application of Systemic-Functional Linguistics in Discourse Analysis
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作者 王斌花 《海外英语》 2013年第20期241-243,共3页
Systemic-functional linguistics considers function and semantics as the basis of human language and communicative activity. In recent years, Systemic-functional linguistics has been applied in such areas as natural la... Systemic-functional linguistics considers function and semantics as the basis of human language and communicative activity. In recent years, Systemic-functional linguistics has been applied in such areas as natural language processing, early language learning, language education, stylistics, foreign language teaching, translation and stylistics. It sheds new light on the further application of this linguistic theory in other fields. 展开更多
关键词 systemic-functional LINGUISTICS functionAL linguis
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The Jaffa Transform for Hessian Matrix Systems and the Laplace Equation
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作者 Daniel A. Jaffa 《Journal of Applied Mathematics and Physics》 2024年第1期98-125,共28页
Hessian matrices are square matrices consisting of all possible combinations of second partial derivatives of a scalar-valued initial function. As such, Hessian matrices may be treated as elementary matrix systems of ... Hessian matrices are square matrices consisting of all possible combinations of second partial derivatives of a scalar-valued initial function. As such, Hessian matrices may be treated as elementary matrix systems of linear second-order partial differential equations. This paper discusses the Hessian and its applications in optimization, and then proceeds to introduce and derive the notion of the Jaffa Transform, a new linear operator that directly maps a Hessian square matrix space to the initial corresponding scalar field in nth dimensional Euclidean space. The Jaffa Transform is examined, including the properties of the operator, the transform of notable matrices, and the existence of an inverse Jaffa Transform, which is, by definition, the Hessian matrix operator. The Laplace equation is then noted and investigated, particularly, the relation of the Laplace equation to Poisson’s equation, and the theoretical applications and correlations of harmonic functions to Hessian matrices. The paper concludes by introducing and explicating the Jaffa Theorem, a principle that declares the existence of harmonic Jaffa Transforms, which are, essentially, Jaffa Transform solutions to the Laplace partial differential equation. 展开更多
关键词 Hessian Matrices Jacobian Matrices Laplace Equation Linear Partial Differential Equations systems of Partial Differential Equations Harmonic functions Incompressible and Irrotational Fluid Mechanics
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An Overview of Systematic-Functional Grammar
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作者 瞿冬梅 《海外英语》 2012年第3X期260-262,共3页
The key notions in Halliday's Systematic Grammar and Functional Grammar are first summarized, and then contrasted with Chomsky's Transformational-Generative Grammar. Results show that Systematic-Functional Gra... The key notions in Halliday's Systematic Grammar and Functional Grammar are first summarized, and then contrasted with Chomsky's Transformational-Generative Grammar. Results show that Systematic-Functional Grammar could be viewed as complementa ry to Transformational-Generative Grammar. They combine to reveal the whole picture of language. 展开更多
关键词 systemIC GRAMMAR functionAL GRAMMAR TRANSFORMATION
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Grain production space reconstruction and land system function tradeoffs in China 被引量:2
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作者 Fei Li Zhangxuan Qin +4 位作者 Xiaolin Liu Zehui Chen Xiaoli Wei Qiumeng Zhang Min Lei 《Geography and Sustainability》 2021年第1期22-30,共9页
Grain production space reconstruction referred to the changes in the quantity,quality and pattern of grain produc-tion space caused by functional tradeoffs and conflicts between grain production space,urban-rural deve... Grain production space reconstruction referred to the changes in the quantity,quality and pattern of grain produc-tion space caused by functional tradeoffs and conflicts between grain production space,urban-rural development space,and ecological service space.Exploring tradeoffs between land system functions caused by grain produc-tion space reconstruction was particularly important for ensuring food security,promoting the construction of ecological civilization,and achieving sustainable development.Therefore,this study identified four relationships of land system functions during the process of grain production space reconstruction(1980-2018)in China by using Set Pair Analysis.Research results showed that the reconstruction of grain production space was achieved mainly through three pathways:Grain for Green,deforestation and reclamation,and urban expansion.Generally,ecological service had spatial negative correlation with grain production,economic development and population carrying capacity(P<0.01),but grain production,economic development and population carrying capacity were positively correlated with each other(P<0.01).In the process of grain production space reconstruction,eco-logical services and economic development,ecological services and population carrying capacity had all shown inverse synergies;there was a tradeoffbetween grain production and ecological services,a codirectional tradeoffbetween grain production and economic development,but a strong synergy between economic development and population carrying capacity.However,the functions of land systems only appeared as synergies or tradeoffs,and there were no inverse synergies and codirectional tradeoffs in the separate processes of Grain for Green,deforestation and reclamation,and urban expansion.It can be concluded that the relationships between land system functions were relatively simple in a single process,but it became complex and diverse when multiple processes were integrated for system analysis. 展开更多
关键词 Land system function TRADEOFFS SYNERGY Grain production space reconstruction Set Pair Analysis
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EXISTENCE OF POSITIVE SOLUTION FOR A TWO-PATCHES COMPETITION SYSTEM WITH DIFFUSION AND TIME DELAY AND FUNCTIONAL RESPONSE 被引量:12
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作者 LiBiwen ZengXianwu 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2003年第1期1-8,共8页
By using the continuation theorem of coincidence theory, the existence of a positive periodic solution for a two patches competition system with diffusion and time delay and functional responsex [FK(W1*3/4。*2/3]... By using the continuation theorem of coincidence theory, the existence of a positive periodic solution for a two patches competition system with diffusion and time delay and functional responsex [FK(W1*3/4。*2/3]′ 1 (t)=x 1(t)a 1(t)-b 1(t)x 1(t)-c 1(t)y(t)1+m(t)x 1(t)+D 1(t)[x 2(t)-x 1(t)], x [FK(W1*3/4。*2/3]′ 2 (t)=x 2(t)a 2(t)-b 2(t)x 2(t)-c 2(t)∫ 0 -τ k(s)x 2(t+s) d s+D 2(t)[x 1(t)-x 2(t)], y′(t)=y(t)a 3(t)-b 3(t)y(t)-c 3(t)x 1(t)1+m(t)x 1(t)is established, where a i(t),b i(t),c i(t)(i=1,2,3),m(t) and D i(t)(i=1,2) are all positive periodic continuous functions with period w >0, τ is a nonnegative constant and k(s) is a continuous nonnegative function on [- τ ,0]. 展开更多
关键词 periodic solutions competition diffusive system functional response continuation theorem of coincidence degree topological degree.
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REFLECTIVE FUNCTION AND PERIODIC SOLUTION OF DIFFERENTIAL SYSTEMS 被引量:7
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作者 Zhou ZhengxinDept.of Math.,College of Science,Yangzhou Univ.,Yangzhou 225002. 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第1期13-23,共11页
This article deals with the reflective function of the mth-order nonlinear differential systems.The results are applied to discussing the stability property of periodic solutions of these systems.
关键词 higher-order system reflective function periodic solution stability.
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Analysis of the Energy and Environmental Sustainability of a Built Space System: The Case of Patte d’Oie University Campus in Ouagadougou
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作者 Daouda Sawadogo Ousmane Coulibaly +1 位作者 Xavier Chesneau Belkacem Zeghmati 《Energy and Power Engineering》 2024年第5期197-215,共19页
The aim of this study was to carry out a dynamic simulation of the energy and environmental performance of a built space system, with a view to assessing its energy and environmental class. The use of a simulation and... The aim of this study was to carry out a dynamic simulation of the energy and environmental performance of a built space system, with a view to assessing its energy and environmental class. The use of a simulation and modeling tool, supported by various methodological references, formed the basis of our approach. Adopting a systemic perspective, we described the structural and functional aspects of the systems making up built spaces, as well as the associated energy flows. Our approach was also based on a typology, taking into account typical days, structural and functional configurations at different scales and angles of observation. The analysis tool we developed in Java was applied to the built space system of the Patte d’Oie university campus in Ouagadougou. Annual electricity consumption was measured at 124387.34 kWh, closely aligned with the average annual electricity bill (125224.31 kWh), with a maximum relative deviation of 1%, followed by a carbon emission balance of 58337.66 kg eq CO<sub>2</sub> per year. This validation confirmed the effectiveness of our tool. In addition, following the analysis of electricity consumption using our tool, the university campus was classified in energy class B and environmental class C. These results will be based on the emission factors of the energy mix of the West African Economic and Monetary Union (WAEMU) territory, with particular emphasis on Burkina Faso. 展开更多
关键词 Energy function Energy Class Carbon Footprint Built Space Consumption Item systemic Approach Typological Approach
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The Application of Systemic Functional Grammar to the Analysis of Features of American Spokesman’s Language 被引量:1
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作者 李玲玉 《海外英语》 2020年第1期246-247,249,共3页
The spokesman's language is official,flexible and public-oriented,to study how it makes sense through varied linguis-tic function is of great importance.Under the framework of systemic-functional grammar,this thes... The spokesman's language is official,flexible and public-oriented,to study how it makes sense through varied linguis-tic function is of great importance.Under the framework of systemic-functional grammar,this thesis focuses on the linguistic fea-tures of American spokesman's language from perspectives of ideational,interpersonal and textual functions.This thesis includes three parts.Part One introduces background and layout of the study.Part Two is a analysis of America spokesperson's language by SF grammar.Part Three ends with the conclusion. 展开更多
关键词 SPOKESMAN systemic-functional Grammar Linguistic Features
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Modified scaling function projective synchronization of chaotic systems 被引量:1
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作者 徐玉华 周武能 方建安 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第9期110-114,共5页
This paper investigates a kind of modified scaling function projective synchronization of uncertain chaotic systems using an adaptive controller. The given scaling function in the new method can be an equilibrium poin... This paper investigates a kind of modified scaling function projective synchronization of uncertain chaotic systems using an adaptive controller. The given scaling function in the new method can be an equilibrium point; a periodic orbit, or even a chaotic attractor in the phase space. Based on LaSalle's invariance set principle, the adaptive control law is derived to make the states of two chaotic systems function projective synchronized. Some numerical examples are also given to show the effectiveness of the proposed method. 展开更多
关键词 chaotic system function projective synchronization scaling function
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Static/dynamic Analysis of Functionally Graded and Layered Magneto-electro-elastic Plate/pipe under Hamiltonian System 被引量:1
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作者 代海涛 《Chinese Journal of Aeronautics》 SCIE EI CSCD 2008年第1期35-42,共8页
The 3-dimensional couple equations of magneto-electro-elastic structures are derived under Hamiltonian system based on the Hamilton principle. The problem of single sort of variables is converted into the problem of d... The 3-dimensional couple equations of magneto-electro-elastic structures are derived under Hamiltonian system based on the Hamilton principle. The problem of single sort of variables is converted into the problem of double sorts of variables, and the Hamilton canonical equations are established. The 3-dimensional problem of magneto-electro-elastic structure which is investigated in Euclidean space commonly is converted into symplectic system. At the same time the Lagrange system is converted into Hamiltonian system. As an example, the dynamic characteristics of the simply supported functionally graded magneto-electro-elastic material (FGMM) plate and pipe are investigated. Finally, the problem is solved by symplectic algorithm. The results show that the physical quantities of displacement, electric potential and magnetic potential etc. change continuously at the interfaces between layers under the transverse pressure while some other physical quantities such as the stress, electric and magnetic displacement are not continuous. The dynamic stiffness is increased by the piezoelectric effect while decreased by the piezomagnetic effect. 展开更多
关键词 functionally graded magneto-electro-elastic material Hamiltonian system symplectic algorithm
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Systematic analysis of corporate environmental responsibility:elements,structure,function,and principles 被引量:4
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作者 Hong Wang 《Chinese Journal of Population,Resources and Environment》 2016年第2期96-104,共9页
Corporate Environmental Responsibility(CER) is the subsystem of Corporate Social Responsibility(CSR),which continues to increase prominence in the global economy.Nowadays,CER becomes more important in corporate sustai... Corporate Environmental Responsibility(CER) is the subsystem of Corporate Social Responsibility(CSR),which continues to increase prominence in the global economy.Nowadays,CER becomes more important in corporate sustainable development.Based on Carroll's pyramid mode of CSR,this article explores the systematic feature of CER.From a systematic perspective,it sorts out its elements,structure,function,and principles of CER.And the four levels of economic,legal,ethical,and charitable structure are emphasized.With these considerations interpreted into practice,success will be achieved in potential cost savings,technological innovation,increased public acceptance,and better relations with governments. 展开更多
关键词 Corporate Social Responsibility(CSR) Corporate Environmental Responsibility(CER) system STRUCTURE function PRINCIPLE
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Metaphor in Advertising Language from Systemic Functional Grammar Perspective
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作者 王晓芳 张希永 《海外英语》 2012年第20期259-263,共5页
Metaphor is a common phenomenon in real life.It refers to a figure of speech in which an implied comparison is made between two unlike things that actually have something in common.As for advertising,foreign studies f... Metaphor is a common phenomenon in real life.It refers to a figure of speech in which an implied comparison is made between two unlike things that actually have something in common.As for advertising,foreign studies focus on the analysis of ap plication and effects of metaphor.Based on the historical and current studies on metaphor,this paper aims at analyzing metaphor and its functions in advertising from systemic functional grammar perspective.It pointed out that metaphor,a rhetoric method in advertising language,has many functions,namely,politeness,imagination,subjectivity,objectivity,and textual cohesion,etc.Thus,metaphor can be seen as an important sales strategy,helping the advertisers to establish a good interpersonal relationship with the target audience so as to reach their business aims.In addition,it is also of great importance in that it can stimulate our in terest to learn English,and help us to improve English reading,understanding and writing. 展开更多
关键词 systemIC functionAL GRAMMAR METAPHOR ADVERTISING l
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THE EXISTENCE OF A LIAPUNOV FUNCTIONAL FOR LINEAR DELAY SYSTEM 被引量:1
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作者 ZhangShengxiang ZhengZuxiu 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2002年第3期273-276,共4页
The delay systemx·(t)=Ax(t)+Bx(t-r)is considered. The necessary and sufficient conditions of the existence of a kind of Liapunov functional for the system are given.
关键词 delay system Liapunov functional all-delay stability.
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Construction of Control Lyapunov Functions for a Class of Nonlinear Systems 被引量:5
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作者 CAI Xiu-Shan HAN Zheng-Zhi WANG Xiao-Dong 《自动化学报》 EI CSCD 北大核心 2006年第5期796-799,共4页
The construction of control Lyapunov functions for a class of nonlinear systems is considered. We develop a method by which a control Lyapunov function for the feedback linearizable part can be constructed systematica... The construction of control Lyapunov functions for a class of nonlinear systems is considered. We develop a method by which a control Lyapunov function for the feedback linearizable part can be constructed systematically via Lyapunov equation. Moreover, by a control Lyapunov function of the feedback linearizable part and a Lyapunov function of the zero dynamics, a control Lyapunov function for the overall nonlinear system is established. 展开更多
关键词 Nonlinear systems control Lyapunov functions semiglobal stabilization zero dynamics.
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