Aqueous zinc-ion batteries are a kind of attractive power supply devices due to their high energy, environmental benignity, and intrinsic safety. In recent years, tremendous enthusiasm has been devoted to the function...Aqueous zinc-ion batteries are a kind of attractive power supply devices due to their high energy, environmental benignity, and intrinsic safety. In recent years, tremendous enthusiasm has been devoted to the functionalities of aqueous zinc-ion batteries, aiming to extend their potential applications in multiple dimensions and multiple scales. Here, the latest advances in the design, construction, and performance evaluation of aqueous zinc-ion batteries are summarized. The focus is on various functionalities such as flexibility, self-healing, self-charging, and miniaturization. We also highlight the materials and structures that have been engineered to realize these functionalities. Finally, we offer some general insights into the challenges and chances in such exciting field.展开更多
Sodium-sulfur(Na–S)batteries that utilize earth-abundant materials of Na and S have been one of the hottest topics in battery research.The low cost and high energy density make them promising candidates for next-gene...Sodium-sulfur(Na–S)batteries that utilize earth-abundant materials of Na and S have been one of the hottest topics in battery research.The low cost and high energy density make them promising candidates for next-generation storage technologies as required in the grid and renewable energy.In recent years,extensive efforts have been devoted to the diversity and functionalities of Na–S batteries,aiming to extend their potential applications across multiple temporal and spatial dimensions.Here,we summarize the unconventional designs for the functionalities of Na–S batteries such as flexible batteries,solid-state cells,flame resistance,and operation at extreme temperatures.By highlighting these design strategies that help to realize the functionalities,we hope this review offers a pathway to foster the bright future of Na–S batteries in diverse applications.展开更多
This paper presents a procedure to develop fragility curves of structures equipped with TMD considering multiple failure functions.The failure criteria considered are maximum inter-story drift ratio as a safety criter...This paper presents a procedure to develop fragility curves of structures equipped with TMD considering multiple failure functions.The failure criteria considered are maximum inter-story drift ratio as a safety criterion,maximum absolute acceleration as a convenience criterion and TMD stroke length.The relationship between intensity measure and responses of the structure was assumed to follow the power-law model,and a regression analysis was used to estimate its properties.A nonlinear eight-story shear building subjected to near-fault earthquakes was used for the numerical studies.Fragility curves using multiple and single failure functions for an uncontrolled structure and a structure equipped with optimal TMDs were developed.Numerical analysis showed that using multiple failure functions led to increasing the fragility when compared with using the single failure function for both the uncontrolled and controlled structures.However,TMDs slightly reduced the seismic fragility and have the capability to improve the reliability of the structure.Also,it was found that the fragility was significantly influenced by the values of the capacity thresholds of both the acceleration of the structure and TMD stroke length,which should be selected by considering the target performance and application of the structure and control device.展开更多
In this paper, both Fritz John and Karush-Kuhn-Tucker necessary optimality conditions are established for a (weakly) LU-efficient solution in the considered nonsmooth multiobjective programming problem with the mult...In this paper, both Fritz John and Karush-Kuhn-Tucker necessary optimality conditions are established for a (weakly) LU-efficient solution in the considered nonsmooth multiobjective programming problem with the multiple interval-objective function. Further, the sufficient optimality conditions for a (weakly) LU-efficient solution and several duality results in Mond-Weir sense are proved under assumptions that the functions constituting the considered nondifferentiable multiobjective programming problem with the multiple interval- objective function are convex.展开更多
In the present paper the transformation of symmetric Markov processes by symmetric martingale multiplicative functionals is studied and the corresponding Dirichlet form is formulated.
This paper is devoted to investigating the solutions of refinement equations of the form Ф(x)=∑α∈Z^s α(α)Ф(Mx-α),x∈R^s,where the vector of functions Ф = (Ф1,… ,Фr)^T is in (L1(R^s))^r, α =(...This paper is devoted to investigating the solutions of refinement equations of the form Ф(x)=∑α∈Z^s α(α)Ф(Mx-α),x∈R^s,where the vector of functions Ф = (Ф1,… ,Фr)^T is in (L1(R^s))^r, α =(α(α))α∈Z^s is an infinitely supported sequence of r × r matrices called the refinement mask, and M is an s × s integer matrix such that lim n→∞ M^-n =0, with m = detM. Some properties about the solutions of refinement equations axe obtained.展开更多
The present work aims to determine the solution of trigonometric functional equation f with involution from group to field by using the properties of involution function, and the solution and Ulam-Hyers stability of t...The present work aims to determine the solution of trigonometric functional equation f with involution from group to field by using the properties of involution function, and the solution and Ulam-Hyers stability of the trigonometric functional equation are also discussed. Furthermore, this method generalizes the main theorem and gives the supplement in some reference.展开更多
The basic principles of the partial and multiple coherence ananlysis and their utilization on vibration source identification are discussed in detail in this paper. The partial coherence analysis is the effective meth...The basic principles of the partial and multiple coherence ananlysis and their utilization on vibration source identification are discussed in detail in this paper. The partial coherence analysis is the effective method of vibration source identification in multiple input single output systems.Formerly, there was not any this kind of function in the signal processor, and there was not any special software too. The software which we developed and used in the 7T 17S signal processor has this function. This software can be used not only for the partial and multiple coherence analysis of signal, but also for the correlation analysis, power spectrum analysis, transfer function analysis et al.We used this software to make the identifcation of the vibration source of the car floor board of electrical measuring vehicle, and to find the main factors which effect the vibration of the car board.The excellent result was obtained. This method can also be used for making the identifications of noise source and other sources.展开更多
The notion of a sort of biorthogonal multiple vector-valued bivariate wavelet packets,which are associated with a quantity dilation matrix,is introduced.The biorthogonality property of the multiple vector-valued wavel...The notion of a sort of biorthogonal multiple vector-valued bivariate wavelet packets,which are associated with a quantity dilation matrix,is introduced.The biorthogonality property of the multiple vector-valued wavelet packets in higher dimensions is studied by means of Fourier transform and integral transform biorthogonality formulas concerning these wavelet packets are obtained.展开更多
[ Objective] The multiple mean generational function (MMGF) method was applied to forecast the annual number of typhoons (TYs) over the Western North Pacific (WNP). [Method]The method yields a number of predicto...[ Objective] The multiple mean generational function (MMGF) method was applied to forecast the annual number of typhoons (TYs) over the Western North Pacific (WNP). [Method]The method yields a number of predictors by mean generational function based on the rolling 50- year data of TYs frequency and sunspot number, and was repeated to generate forecasts year after year by optimal subset regression. [ Result] The results showed a reasonably high predictive ability dudng period 2000 -2010, with an average root mean square (RMSE) value of 1.92 and a mean absolute error (MAE) value of 1.64. [ Conclusion] Although the MMGF method needs further validation in the practical operation, it already has strong potential for the improvement of skill at forecasting annual frequency of TYs in the WNP.展开更多
The order of magnitude of multiple Fourier coefficients of complex valued functions of generalized bounded variations like (∧^1,.. .,∧^N)BV^(p) and r-BV, over [0,2π]^ N, are estimated.
This paper investigates the finite-time H<sub>∞</sub> control problem of switched nonlinear systems via state-dependent switching and state feedback control. Unlike the existing approach based on time-dep...This paper investigates the finite-time H<sub>∞</sub> control problem of switched nonlinear systems via state-dependent switching and state feedback control. Unlike the existing approach based on time-dependent switching strategy, in which the switching instants must be given in advance, the state-dependent switching strategy is used to design switching signals. Based on multiple Lyapunov-like functions method, several criteria for switched nonlinear systems to be finite-time H<sub>∞</sub> control are derived. Finally, a numerical example with simulation results is provided to show the validity of the conclusions.展开更多
Based on winter nursery and shuttle breeding, Hainan National Breeding and Multiplication (HNBM), with off-season breeding and seed production as the essence, has become a national strategic resource. The way of HNB...Based on winter nursery and shuttle breeding, Hainan National Breeding and Multiplication (HNBM), with off-season breeding and seed production as the essence, has become a national strategic resource. The way of HNBM rising to the national strategy was analyzed through the aspects of technology features, historical characteristics, irreplaceability, function and value hierarchy, and the key problems. As the major achievement of the practice of scientific research and historical selec- tion, HNBM played an irreplaceable role in the climatic conditions, scientific breed- ing, and seed production in disaster relief, protecting the safety of the seed industry and Iocational advantages. Based on the analysis on the functions, values and ex- isted problems of HNBM, the function and value hierarchical structure of HNBM was established through introducing concepts of value engineering, industrial clusters and regional economy. But to fully achieve the industrial clustering development and functional values of HNBM, it needed to solve the key problems existed in top-level planning, experimental bases, system design, hardware construction and ecological security. Some suggestions were put forward in this paper, including setting up key scientific research protection zones, improving the regulations and policies safeguard mechanism and management system of HNBM, drawing up and carrying out the base development planning of HNBM, and striving for financial support from national policies.展开更多
The exponential stabilization problem for finite dimensional switched systems is extended to the infinite dimensional distributed parameter systems in the Hilbert space. Based on the semigroup theory, by applying the ...The exponential stabilization problem for finite dimensional switched systems is extended to the infinite dimensional distributed parameter systems in the Hilbert space. Based on the semigroup theory, by applying the multiple Lyapunov function method, the exponential stabilization conditions are derived. These conditions are given in the form of linear operator inequalities where the decision variables are operators in the Hilbert space; while the stabilization properties depend on the switching rule. Being applied to the two-dimensional heat switched propagation equations with the Dirichlet boundary conditions, these linear operator inequalities are transformed into standard linear matrix inequalities. Finally, two examples are given to illustrate the effectiveness of the proposed results.展开更多
This paper deals with the problem of switching between an open-loop estimator and a close-loop estimator for compensating transmission error and packet dropout of networked control systems. Switching impulse is consid...This paper deals with the problem of switching between an open-loop estimator and a close-loop estimator for compensating transmission error and packet dropout of networked control systems. Switching impulse is considered in order to reduce the error between theory and application, a sufficient condition for exponential stabilization of networked control systems under a given switching rule is presented by multiple Lyapunov-like functions. These results are presented for both continuous-time and discrete-time domains. Controllers are designed by means of linear matrix inequalities. Sim- ulation results show the feasibility and efficiency of the proposed method.展开更多
This paper is concerned with controller synthesis for linear switched systems with actuator saturation. Based on common Lyapunov function technique and multiple-Lyapunov function technique, two methods for designing s...This paper is concerned with controller synthesis for linear switched systems with actuator saturation. Based on common Lyapunov function technique and multiple-Lyapunov function technique, two methods for designing state feedback controller are proposed respectively in terms of linear matrix inequalities for the switched systems with saturation. An approach on enlarging the attractive domain is then investigated, The application of the presented approach is illustrated finally by a numerical example.展开更多
This paper focuses on the H_∞ model reference tracking control for a switched linear parameter-varying(LPV)model representing an aero-engine. The switched LPV aeroengine model is built based on a family of linearized...This paper focuses on the H_∞ model reference tracking control for a switched linear parameter-varying(LPV)model representing an aero-engine. The switched LPV aeroengine model is built based on a family of linearized models.Multiple parameter-dependent Lyapunov functions technique is used to design a tracking control law for the desirable H_∞ tracking performance. A control synthesis condition is formulated in terms of the solvability of a matrix optimization problem.Simulation result on the aero-engine model shows the feasibility and validity of the switching tracking control scheme.展开更多
The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to...The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.展开更多
A sufficient condition for the existence of nonfragile state-feedback controllers and a switching law for a class of uncertain switching fuzzy time-delay systems are proposed based on the multiple Lyapunov functions t...A sufficient condition for the existence of nonfragile state-feedback controllers and a switching law for a class of uncertain switching fuzzy time-delay systems are proposed based on the multiple Lyapunov functions technique, under the assumption that the controller gain to be designed has variations. The corresponding results are all formulated in terms of linear matrix inequalities (LMIs). Simulation results show the effectiveness of the design method.展开更多
This paper proposes a method for the stability analysis of deterministic switched systems.Two motivational examples are introduced (nonholonomic system and constrained pendulum).The finite collection of models consi...This paper proposes a method for the stability analysis of deterministic switched systems.Two motivational examples are introduced (nonholonomic system and constrained pendulum).The finite collection of models consists of nonlinear models,and a switching sequence is arbitrary.It is supposed that there is no jump in the state at switching instants,and there is no Zeno behavior,i.e.,there is a finite number of switches on every bounded interval.For the analysis of deterministic switched systems,the multiple Lyapunov functions are used,and the global exponential stability is proved.The exponentially stable equilibrium of systems is relevant for practice because such systems are robust to perturbations.展开更多
基金Sponsored by the Fundamental Research Program of Shanxi Province (Grant No.202103021223019)the Science and Technology Major Project of Shanxi (Grant No. 202101030201022)+1 种基金the National Natural Science Foundation of China (Grant Nos.52172219, 51872192)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China (Grant No.19KJA170001)。
文摘Aqueous zinc-ion batteries are a kind of attractive power supply devices due to their high energy, environmental benignity, and intrinsic safety. In recent years, tremendous enthusiasm has been devoted to the functionalities of aqueous zinc-ion batteries, aiming to extend their potential applications in multiple dimensions and multiple scales. Here, the latest advances in the design, construction, and performance evaluation of aqueous zinc-ion batteries are summarized. The focus is on various functionalities such as flexibility, self-healing, self-charging, and miniaturization. We also highlight the materials and structures that have been engineered to realize these functionalities. Finally, we offer some general insights into the challenges and chances in such exciting field.
基金supported by the National Natural Science Foundation of China(52172219 and 51872192)the Natural Science Foundation of the Jiangsu Higher Education Institutions of China(19KJA170001)+1 种基金the Fundamental Research Program of Shanxi Province(202103021223019)Science and Technology Major Project of Shanxi(No.202101030201022)
文摘Sodium-sulfur(Na–S)batteries that utilize earth-abundant materials of Na and S have been one of the hottest topics in battery research.The low cost and high energy density make them promising candidates for next-generation storage technologies as required in the grid and renewable energy.In recent years,extensive efforts have been devoted to the diversity and functionalities of Na–S batteries,aiming to extend their potential applications across multiple temporal and spatial dimensions.Here,we summarize the unconventional designs for the functionalities of Na–S batteries such as flexible batteries,solid-state cells,flame resistance,and operation at extreme temperatures.By highlighting these design strategies that help to realize the functionalities,we hope this review offers a pathway to foster the bright future of Na–S batteries in diverse applications.
文摘This paper presents a procedure to develop fragility curves of structures equipped with TMD considering multiple failure functions.The failure criteria considered are maximum inter-story drift ratio as a safety criterion,maximum absolute acceleration as a convenience criterion and TMD stroke length.The relationship between intensity measure and responses of the structure was assumed to follow the power-law model,and a regression analysis was used to estimate its properties.A nonlinear eight-story shear building subjected to near-fault earthquakes was used for the numerical studies.Fragility curves using multiple and single failure functions for an uncontrolled structure and a structure equipped with optimal TMDs were developed.Numerical analysis showed that using multiple failure functions led to increasing the fragility when compared with using the single failure function for both the uncontrolled and controlled structures.However,TMDs slightly reduced the seismic fragility and have the capability to improve the reliability of the structure.Also,it was found that the fragility was significantly influenced by the values of the capacity thresholds of both the acceleration of the structure and TMD stroke length,which should be selected by considering the target performance and application of the structure and control device.
文摘In this paper, both Fritz John and Karush-Kuhn-Tucker necessary optimality conditions are established for a (weakly) LU-efficient solution in the considered nonsmooth multiobjective programming problem with the multiple interval-objective function. Further, the sufficient optimality conditions for a (weakly) LU-efficient solution and several duality results in Mond-Weir sense are proved under assumptions that the functions constituting the considered nondifferentiable multiobjective programming problem with the multiple interval- objective function are convex.
基金in partby the National Natural Science Founda-tion of China(1 950 1 0 36)
文摘In the present paper the transformation of symmetric Markov processes by symmetric martingale multiplicative functionals is studied and the corresponding Dirichlet form is formulated.
基金Supported by the National Natural Science Foundation of China (10071071)
文摘This paper is devoted to investigating the solutions of refinement equations of the form Ф(x)=∑α∈Z^s α(α)Ф(Mx-α),x∈R^s,where the vector of functions Ф = (Ф1,… ,Фr)^T is in (L1(R^s))^r, α =(α(α))α∈Z^s is an infinitely supported sequence of r × r matrices called the refinement mask, and M is an s × s integer matrix such that lim n→∞ M^-n =0, with m = detM. Some properties about the solutions of refinement equations axe obtained.
文摘The present work aims to determine the solution of trigonometric functional equation f with involution from group to field by using the properties of involution function, and the solution and Ulam-Hyers stability of the trigonometric functional equation are also discussed. Furthermore, this method generalizes the main theorem and gives the supplement in some reference.
文摘The basic principles of the partial and multiple coherence ananlysis and their utilization on vibration source identification are discussed in detail in this paper. The partial coherence analysis is the effective method of vibration source identification in multiple input single output systems.Formerly, there was not any this kind of function in the signal processor, and there was not any special software too. The software which we developed and used in the 7T 17S signal processor has this function. This software can be used not only for the partial and multiple coherence analysis of signal, but also for the correlation analysis, power spectrum analysis, transfer function analysis et al.We used this software to make the identifcation of the vibration source of the car floor board of electrical measuring vehicle, and to find the main factors which effect the vibration of the car board.The excellent result was obtained. This method can also be used for making the identifications of noise source and other sources.
基金Supported by Natural Science Foundation of Henan Province(0511013500)
文摘The notion of a sort of biorthogonal multiple vector-valued bivariate wavelet packets,which are associated with a quantity dilation matrix,is introduced.The biorthogonality property of the multiple vector-valued wavelet packets in higher dimensions is studied by means of Fourier transform and integral transform biorthogonality formulas concerning these wavelet packets are obtained.
基金Supported by the Natural Science Fund of Education Department of Anhui Province (KJ2012Z097)
文摘[ Objective] The multiple mean generational function (MMGF) method was applied to forecast the annual number of typhoons (TYs) over the Western North Pacific (WNP). [Method]The method yields a number of predictors by mean generational function based on the rolling 50- year data of TYs frequency and sunspot number, and was repeated to generate forecasts year after year by optimal subset regression. [ Result] The results showed a reasonably high predictive ability dudng period 2000 -2010, with an average root mean square (RMSE) value of 1.92 and a mean absolute error (MAE) value of 1.64. [ Conclusion] Although the MMGF method needs further validation in the practical operation, it already has strong potential for the improvement of skill at forecasting annual frequency of TYs in the WNP.
文摘The order of magnitude of multiple Fourier coefficients of complex valued functions of generalized bounded variations like (∧^1,.. .,∧^N)BV^(p) and r-BV, over [0,2π]^ N, are estimated.
文摘This paper investigates the finite-time H<sub>∞</sub> control problem of switched nonlinear systems via state-dependent switching and state feedback control. Unlike the existing approach based on time-dependent switching strategy, in which the switching instants must be given in advance, the state-dependent switching strategy is used to design switching signals. Based on multiple Lyapunov-like functions method, several criteria for switched nonlinear systems to be finite-time H<sub>∞</sub> control are derived. Finally, a numerical example with simulation results is provided to show the validity of the conclusions.
基金Supported by the Natural Science Foundation of Hainan Province(313114)the Sanya Science Project(2013YD89)the Social Science Project(SYSK14-08)~~
文摘Based on winter nursery and shuttle breeding, Hainan National Breeding and Multiplication (HNBM), with off-season breeding and seed production as the essence, has become a national strategic resource. The way of HNBM rising to the national strategy was analyzed through the aspects of technology features, historical characteristics, irreplaceability, function and value hierarchy, and the key problems. As the major achievement of the practice of scientific research and historical selec- tion, HNBM played an irreplaceable role in the climatic conditions, scientific breed- ing, and seed production in disaster relief, protecting the safety of the seed industry and Iocational advantages. Based on the analysis on the functions, values and ex- isted problems of HNBM, the function and value hierarchical structure of HNBM was established through introducing concepts of value engineering, industrial clusters and regional economy. But to fully achieve the industrial clustering development and functional values of HNBM, it needed to solve the key problems existed in top-level planning, experimental bases, system design, hardware construction and ecological security. Some suggestions were put forward in this paper, including setting up key scientific research protection zones, improving the regulations and policies safeguard mechanism and management system of HNBM, drawing up and carrying out the base development planning of HNBM, and striving for financial support from national policies.
基金The National Natural Science Foundation of China(No.61273119,61104068,61374038)the Natural Science Foundation of Jiangsu Province(No.BK2011253)
文摘The exponential stabilization problem for finite dimensional switched systems is extended to the infinite dimensional distributed parameter systems in the Hilbert space. Based on the semigroup theory, by applying the multiple Lyapunov function method, the exponential stabilization conditions are derived. These conditions are given in the form of linear operator inequalities where the decision variables are operators in the Hilbert space; while the stabilization properties depend on the switching rule. Being applied to the two-dimensional heat switched propagation equations with the Dirichlet boundary conditions, these linear operator inequalities are transformed into standard linear matrix inequalities. Finally, two examples are given to illustrate the effectiveness of the proposed results.
基金This work was supported by the National Natural Science Foundation of China (No.60574013, 60274009), and the Natural Science Fundation ofLiaoning Province (No.20032020).
文摘This paper deals with the problem of switching between an open-loop estimator and a close-loop estimator for compensating transmission error and packet dropout of networked control systems. Switching impulse is considered in order to reduce the error between theory and application, a sufficient condition for exponential stabilization of networked control systems under a given switching rule is presented by multiple Lyapunov-like functions. These results are presented for both continuous-time and discrete-time domains. Controllers are designed by means of linear matrix inequalities. Sim- ulation results show the feasibility and efficiency of the proposed method.
基金This work was supported by the National Natural Science Foundation of China(No. 60474034).
文摘This paper is concerned with controller synthesis for linear switched systems with actuator saturation. Based on common Lyapunov function technique and multiple-Lyapunov function technique, two methods for designing state feedback controller are proposed respectively in terms of linear matrix inequalities for the switched systems with saturation. An approach on enlarging the attractive domain is then investigated, The application of the presented approach is illustrated finally by a numerical example.
基金supported by the National Natural Science Foundation of China(61304058,61233002)IAPI Fundamental Research Funds(2013ZCX03-01)
文摘This paper focuses on the H_∞ model reference tracking control for a switched linear parameter-varying(LPV)model representing an aero-engine. The switched LPV aeroengine model is built based on a family of linearized models.Multiple parameter-dependent Lyapunov functions technique is used to design a tracking control law for the desirable H_∞ tracking performance. A control synthesis condition is formulated in terms of the solvability of a matrix optimization problem.Simulation result on the aero-engine model shows the feasibility and validity of the switching tracking control scheme.
基金supported by National Natural Science Foundation of China(No.50675209)the Scientific Research Foundation for the Returned Overseas Chinese Scholars,Ministry of Education of China(No.200724).
文摘The strength of composite plate with different hole-shapes is always one of the most important but complicated issues in the application of the composite material. The holes will lead to mutations and discontinuity to the structure. So the hole-edge stress concentration is always a serious phenomenon. And the phenomenon makes the structure strength decrease very quickly to form dangerous weak points. Most partial damage begins from these weak points. According to the complex variable functions theory, the accurate boundary condition of composite plate with different hole-shapes is founded by conformal mapping method to settle the boundary condition problem of complex hole-shapes. Composite plate with commonly hole-shapes in engineering is studied by several complex variable stress fimction. The boundary integral equations are founded based on exact boundary conditions. Then the exact hole-edge stress analytic solution of composite plate with rectangle holes and wing manholes is resolved. Both of offset axis loadings and its influences on the stress concentration coefficient of the hole-edge are discussed. And comparisons of different loads along various offset axis on the hole-edge stress distribution of orthotropic plate with rectangle hole or wing manhole are made. It can be concluded that hole-edge with continuous variable curvatures might help to decrease the stress concentration coefficient; and smaller angle of outer load and fiber can decrease the stress peak value.
基金supported by the National Natural Science Foundation of China (No.60874024, 60574013, 90816028)the Specialized Research Fund for the Doctoral Program of Higher Education of China (No.200801450019)
文摘A sufficient condition for the existence of nonfragile state-feedback controllers and a switching law for a class of uncertain switching fuzzy time-delay systems are proposed based on the multiple Lyapunov functions technique, under the assumption that the controller gain to be designed has variations. The corresponding results are all formulated in terms of linear matrix inequalities (LMIs). Simulation results show the effectiveness of the design method.
基金supported by the Ministry of Science and Technological Development of the Republic of Serbia (No. TR-3326)
文摘This paper proposes a method for the stability analysis of deterministic switched systems.Two motivational examples are introduced (nonholonomic system and constrained pendulum).The finite collection of models consists of nonlinear models,and a switching sequence is arbitrary.It is supposed that there is no jump in the state at switching instants,and there is no Zeno behavior,i.e.,there is a finite number of switches on every bounded interval.For the analysis of deterministic switched systems,the multiple Lyapunov functions are used,and the global exponential stability is proved.The exponentially stable equilibrium of systems is relevant for practice because such systems are robust to perturbations.