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Mobile payment (m-payment) is no longer an unknown technological innovation due to mobile technology advancement. While many past studies have been conducted in this area, they assume that a user will only need to consider m-payment without cash impediments. Hence, they fail to consider the influence of cash within the study of m-payment. Given this limitation, the study draws on migration, regret, innovation resistance, status quo bias, and incentive theories to examine the switching intention from cash to m-payment based on a push-pull-mooring framework. A total of 250 usable sample sizes were adopted, with the conceptual model empirically validated using a PLS-SEM. All the findings in this study were supported except for the relationship between perceived monetary rewards and switching intention, and the risk barrier and inertia. The findings of this study benefit managers and practitioners from both theoretical and practical backgrounds. [ABSTRACT FROM AUTHOR]

In response to the Scientific Revolution of the 17th century, Immanuel Kant put forward a transcendental philosophy which distinguished between the appearance and the thing-in-itself (das Ding an sich), in the belief that people can only know appearances, but not things-in-themselves. The fact that contemporary philosophy has gone far beyond transcendental philosophy can be seen clearly in the following respects: the response to the Scientific Revolution; the dualistic theory of qualities; the two concepts of the thing-in-itself; and how to know the thing-in-itself. In order to deepen the discussion of the thing-in-itself, it is necessary to introduce probing new questions and attempt to elucidate a switching theory of reality that distinguishes between the meaning-impoverished thing-in-itself and the meaning-rich thing-in-itself, and advocates placing the focus of philosophical thinking on the latter. Basing ourselves on the switching theory of reality and the total perspective concept that it implies allows us to better understand man's place in the universe and the mission of philosophy in the post-metaphysical era. [ABSTRACT FROM AUTHOR]

In this study, we consider a new aspect of belief function or Dempster-Shafer theory to define a belief set and cosine similarity measure between two belief sets under uncertainty. For this purpose, firstly, the concept of belief sets will be represented as a triple vector space that is characterized by truth-belief degree, uncertainty-belief degree; and falsity-belief degree. Then, the cosine similarity measure between two belief sets is proposed to determine the degree of similarity between them. This measure is directly defined upon the framework of Dempster-Shafer theory without switching by other theories. Finally, an application of a new method in the decision-making process is provided in the medical diagnosis, when values were presented on the structure of belief set. Furthermore, a numerical example of the medical diagnosis is presented to show the effectiveness and flexibility of the proposed method. [ABSTRACT FROM AUTHOR]

Nowadays, manufacturing systems are seeking control architectures that offer efficient production performance and reactivity to disruptive events. Dynamic hybrid control architectures are a promising approach as they are not only able to switch dynamically between hierarchical, heterarchical and semi-heterarchical structures, they can also switch the level of coupling between predictive scheduling and reactive control techniques. However, few approaches address an efficient switching process in terms of structure and coupling. This paper presents a switching mechanism framework in dynamic hybrid control architectures, which exploits the advantages of hierarchical manufacturing scheduling systems and heterarchical manufacturing execution systems, and also mitigates the respective reactivity and optimality drawbacks. The main feature in this framework is that it monitors the system dynamics online and shifts between different operating modes to attain the most suitable production control strategy. The experiments were carried out in an emulation of a real manufacturing system to illustrate the benefits of including a switching mechanism in simulated scenarios. The results show that the switching mechanism improves response to disruptions in a global performance indicator as it permits to select the best alternative from several operating modes. [ABSTRACT FROM PUBLISHER]

This article develops a new sampling scheme by variables inspection, namely a quick switching sampling (QSS) system based on the process yield index for lot determination when the quality characteristic is normally distributed with two specification limits. The QSS system can provide a flexible sampling procedure by switching decision policies, normal inspection and tightened inspection. The operating characteristic curve of the proposed QSS system is derived and required to pass through two designed points, acceptable quality level and limiting quality level for satisfying risks simultaneously suffered by the producer and the consumer. The proposed sampling system’s performance is investigated and a comparison with the conventional variables single sampling (VSS) plan is also examined. The results indicate that the proposed system outperforms the VSS plan by requiring a smaller sample size for inspection while retaining the same protection. For practical purposes, the plan parameters’ tables are provided on the basis of various selected quality requirements and risks. Finally, we demonstrate the proposed sampling system using an example taken from a silicone LED lens industry. [ABSTRACT FROM PUBLISHER]

This paper addresses a tool switching problem of a flexible machine with the objective of minimizing the frequency of movements of the tool transporter. A flexible machine must process a set of parts with its production sequence already prescribed. It is assumed that the tool magazine cannot hold enough tools for the parts. Thus, tools may have to be switched between two successive parts in the part sequence. Tools that are required but unavailable at the magazine are transferred from the tool crib by an automatic tool transporter with a limited carrying capacity. We suggest an optimal tooling policy utilizing the concept of early insertions of tools and show the effects of early insertions through computational tests on randomly generated test problems. [ABSTRACT FROM AUTHOR]

Tracking of command constant references is a tracking control problem of fundamental importance. This problem for linear time-varying delay systems in the presence of actuator failures is solved in this article. The linear time-varying delay system with actuator failures is modelled as a switched linear time-varying delay system by utilising switching systems theory and a suitable control scheme. The polytopic technique is employed in order to cope with the time-varying, delay-derivative term in case its absolute value might exceed one. On the grounds of the average dwell-time approach, a switching tracking control law that is immune to actuator failures is designed and the conditions are derived such that the output of the linear time-varying delay system tracks given constant command references. Two illustrative examples along with the respective numerical and simulation results are presented to demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

The problem of medium term production planning and control is compounded in many manufacturing concerns by the wide variety of products and by the presence of stochastic variables. This paper presents a simple heuristic approach to the problem by essentially combining a simple linear decision rule with a switching algorithm to give multi-product control operating within capacity limits. The approach is examined in depth by description of an industrial study and the results of the study suggest that the method requires little computing time, that it is conceptually simple and that it gives good results. It is suggested that the approach could he extremely useful in a wide variety of batch manufacturing environments. [ABSTRACT FROM AUTHOR]

To study why the altruistic cooperation can emerge and maintain among self-interested individuals, researchers across several disciplines have made contributions for the solutions of this fascinating problem. Among this, a most-often used framework to describe cooperative dilemma is the evolutionary game theory. In traditional settings, an ideal hypothesis that individuals can feasibly obtain related partners' pay-offs for strategy updating is often adopted. However, considering the impracticality in acquiring accurate pay-offs of referential objects at each round of interaction, we propose switching probability which is independent of pay-offs and denotes the willingness of any individual shifts to another strategy. Here we provide results for the evolutionary dynamics driven by the switching probability in a three-strategy game model, played by the fully connected populations. The findings inform the befitting design of switching probabilities which maximally promote cooperation. We also derive general results that characterise the interaction of the three strategies: coexistence of multiple strategies or domination by some strategy. [ABSTRACT FROM AUTHOR]

In this paper, we focus on ergodicity and transience of SDEs driven by symmetric -stable processes () with Markovian switching. Some sufficient conditions for ergodicity of several classes of stable processes with Markovian switching are given. Furthermore, an almost necessary and sufficient condition for ergodicity of Ornstein-Uhlenbeck type driven by symmetric -stable processes with Markovian switching is presented. As applications, some examples are provided to illustrate our results. [ABSTRACT FROM AUTHOR]

In this paper, the event-triggered stabilisation problem for a class of switched systems with actuator saturation is investigated. Based on multiple Lyapunov function method and the average dwell time approach, a sufficient condition for exponential stability of such systems under event-triggered state-feedback controller is derived. To avoid Zeno behaviour, it is shown that there exists a positive lower bound for any two consecutive inter-event instants. Finally, two examples are presented to illustrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

In this paper, the cooperative output regulation problem for heterogeneous multi-agent systems is addressed by considering a switched leader dynamics. The switched leader dynamics consists of multiple linear models and a switching rule governing the switches among them. A switched leader is capable of generating various sophisticated reference signals for more complicated multi-agent coordination tasks. A novel distributed hybrid impulsive switching control scheme is proposed to achieve cooperative output regulation. Distributed switching stability is established using the average dwell-time technique with multiple Lyapunov functions. Moreover, the associated distributed control synthesis conditions are formulated in terms of linear matrix inequalities plus linear matrix equations. As a result, both switching rules for the leader and distributed switching protocols for the followers can be jointly synthesised via efficient semi-definite programming. An example has been used to demonstrate the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

This paper considers controllability of multi-agent systems with periodically switching topologies and switching leaders. The concept of m-periodic controllability is proposed, and a criterion for m-periodic controllability is established. The effect of the duration of subsystems on controllability is analysed by utilising a property of analytic functions. In addition, the influence of switching periods on controllability is investigated, and an algorithm is proposed to search for the fewest periods to ensure controllability. A necessary condition for m-periodic controllability is obtained from the perspective of eigenvectors of the subsystems’ Laplacian matrices. For a system with switching leaders, it is proved that switching-leader controllability is equivalent to multiple-leader controllability. Furthermore, both the switching order and the tenure of agents being leaders have no effect on the controllability. Some examples are provided to illustrate the theoretical results. [ABSTRACT FROM AUTHOR]

This paper studies the problem of global finite-time output feedback stabilisation for a class of switched high-order nonlinear systems under arbitrary switchings. Based on adding one power integrator technique, we design a common homogeneous controller to guarantee finite-time stability of the closed-loop switched nonlinear system. An example is given to illustrate the effectiveness of the proposed control scheme. [ABSTRACT FROM AUTHOR]

This paper addresses the adaptive formation control of a group of vertical take-off and landing (VTOL) unmanned aerial vehicles (UAV) with switching-directed interaction topologies. In addition, to tackle the adverse effect of disturbances, a couple of smooth bounded estimators are involved in the procedure design. Exploiting an extraction algorithm, we take advantage of the fully actuated rotational dynamics, to control the translational dynamics of each vehicle. We propose a distributed control scheme such that all vehicles track a desired reference velocity signal while keeping a desired prespecified formation. In this framework, the underlying topology of the agents may switch among several directed graphs, each having a spanning tree. The stability of the overall closed-loop system is proved through Lyapunov function. Finally, simulation results are given to better highlight the effectiveness of the proposed control scheme. [ABSTRACT FROM AUTHOR]

This paper introduces an effective four-level voltage switching state algorithm for direct torque controlled open end winding induction motor drive with two-two level inverters in dual mode. In the recent days, direct torque control of open end winding induction motor drive became an interesting area for researchers because it provides high dynamic performance and instantaneous control of stator flux and torque. It is more important especially in applications like propulsion and hybrid electric vehicles they require ripple free torque. The direct torque control provides high flux, torque ripple, and variable switching frequency. This paper introduces an effective voltage switching state algorithm for an open end winding induction motor drive to reduce torque and flux ripple at different frequencies of operation. The experimental results show that the proposed algorithm reduces torque and flux ripples without losing features of conventional direct torque control (DTC) algorithm and in addition it provides multi-level operation. [ABSTRACT FROM AUTHOR]

In this paper, the problem of adaptive fuzzy tracking control is investigated for switched nonlinear pure-feedback systems under arbitrary switching. By utilising mean value theorem, the considered pure-feedback systems are transformed into a class of switched nonlinear strict-feedback systems. Compared with the existing results, a priori knowledge of control directions is not required. On the other hand, differing from the existing literatures, the piecewise switched adaptive laws are designed to replace the common adaptive laws, which can reduce the conservativeness. Furthermore, the difficulties from how to deal with the unknown control directions and design common virtual control are overcome. Based on the backstepping technique and the common Lyapunov functions, an adaptive fuzzy control scheme is developed to guarantee that all the signals in the closed-loop system are semi-globally uniformly ultimately bounded with the tracking error converging to a neighbourhood of the origin. Simulation results are provided to demonstrate the effectiveness of the proposed techniques. [ABSTRACT FROM PUBLISHER]

This paper studies the differentiability properties of the control-to-state mapping for entropy solutions to a scalar hyperbolic conservation law onwith respect to the switching times of an on/off-control. The switching times between on-modes and off-modes are the control variables of the considered optimization problem, where a general tracking-type functional is minimized. We investigate the differentiability of the reduced objective function, also in the presence of shocks. We show that the stateat some observation timedepends differentiably on the switching times in a generalized sense that implies total differentiability for the composition with a tracking functional. Furthermore, we present an adjoint-based formula for the gradient of the reduced objective functional with respect to the switching times. [ABSTRACT FROM AUTHOR]

This paper presents the first attempt to design a reaching law-based discrete-time sliding mode controller with a relative degree 2 switching variable. The current value of this variable is only affected by the control signal and disturbance generated two time instants ago. It is demonstrated that the new reaching law-based strategy offers a smaller quasi-sliding mode band width when compared to a similar control scheme with relative degree 1 switching variable. This in turn leads to reduced system output error in the control system proposed in the paper. [ABSTRACT FROM AUTHOR]

This paper is concerned with the fixed-time consensus problem of multi-agent systems. Unlike conventional consensus-based investigations, where nonlinear inherent dynamics satisfying the Lipschitz continuous condition is assumed or simply no inherent dynamics is involved for each agent, we are dealing with a more general case: agents with discontinuous nonlinear inherent dynamics. By using non-smooth analysis and fixed-time stability techniques, distributed protocols are proposed to achieve the fixed-time consensus over fixed and switching topology. Then, for a class of linear multi-agent systems, a new distributed controller is proposed to further reduce the calculation cost while achieving the agreement. A distinctive feature of the work is that the estimation of settling time for consensus is independent of initial states of agents, which provides flexibility for applications implemented in unknown environment. Finally, numerical simulations are given to demonstrate the effectiveness of the theoretical results. [ABSTRACT FROM AUTHOR]

Stability of certain classes of nonlinear time-delay switched systems is studied. For the corresponding families of subsystems, conditions of the existence of common Lyapunov–Razumikhin functions are found. The fulfilment of these conditions provides the asymptotic stability of the zero solutions of the considered hybrid systems for any switching law and for any nonnegative delay. Some examples are presented to demonstrate the effectiveness of the obtained results. [ABSTRACT FROM AUTHOR]

This paper considers a class of switched nonlinear systems with time-scaling transformation. A newconcept named ‘time-scaling transformational average dwell time’ is proposed, based on which two stability conditions for the original switched system are established that rely on each mode's dynamics of the transformational switched system and the characteristic of the time-scaling transformation. The new observation significantly extends existing stability results, especially for the case with unstable modes. A numerical example is given to illustrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

A planar three-link passive–active–active (PAA) underactuated mechanical system is a kind of nonlinear system with a passive first joint. The position–posture control objective for the planar PAA system is to move the end effector from an initial position to a target position with a specified posture. This paper presents a switch control strategy to solve the position–posture control problem. First, a Lyapunov function is constructed based on the system control objective. Then, a set of main controllers based on this Lyapunov function are designed. However, the main controllers may make the system stabilise at one of equilibrium points, which is not the system target position. To avoid the above phenomenon, when the system is about to stabilise at one non-target position, the main controllers are switched to a set of sub-controllers, which are designed according to another Lyapunov function constructed based on the control objective of the active links. When the sub-controllers are running, their design parameters are adjusted to try to keep the derivative of the first Lyapunov function being a non-positive function. Therefore, the switch control between the main controllers and the sub-controllers realises the position–posture control objective of the system. Finally, the simulation results demonstrate the effectiveness of the switch control strategy. [ABSTRACT FROM AUTHOR]

In this article, we investigate the pricing of European-style options under a Markovian regime-switching Hull–White interest rate model. The parameters of this model, including the mean-reversion level, the volatility of the stochastic interest rate, and the volatility of an asset’s value, are modulated by an observable, continuous-time, finite-state Markov chain. A closed-form expression for the characteristic function of the logarithmic terminal asset price is derived. Then, using the fast Fourier transform, a price of a European-style option is computed. In a two-state Markov chain case, numerical examples and empirical studies are presented to illustrate the practical implementation of the model. [ABSTRACT FROM AUTHOR]

We propose herein a new portfolio selection method that switches between two distinct asset allocation strategies. An important component is a carefully designed adaptive switching rule, which is based on a machine learning algorithm. It is shown that using this adaptive switching strategy, the combined wealth of the new approach is a weighted average of that of the successive constant rebalanced portfolio and that of the 1/N portfolio. In particular, it is asymptotically superior to the 1/N portfolio under mild conditions in the long run. Applications to real data show that both the returns and the Sharpe ratios of the proposed binary switch portfolio are the best among several popular competing methods over varying time horizons and stock pools. [ABSTRACT FROM PUBLISHER]

In this study, the authors consider the consensus tracking problem for second-order nonlinear multi-agent systems with switching topologies and a time-varying reference state. The dynamics of each agent consists of nonlinear inherent dynamics. In order to reach consensus tracking, a class of nonsmooth control protocols is proposed which only depends on the agent's own information and its neighbours’ information. With the aid of algebraic graph theory, matrix theory, and Lyapunov theory, some corresponding sufficient conditions guaranteeing consensus tracking under the proposed control protocols are derived. Finally, the numerical simulations are given to illustrate the effectiveness of the developed theoretical results. [ABSTRACT FROM AUTHOR]

Robust stabilisation andL2-gain analysis for a class of switched systems with actuator saturation are studied in this paper. The switching signal of the controllers lags behind that of the system modes, which leads to the asynchronous switching between the candidate controllers and the subsystems. By combining the piecewise Lyapunov function method with the convex hull technique, sufficient conditions in terms of LMIs for the solvability of the robust stabilisation and weightedL2-gain problems are presented respectively under the dwell time scheme. Finally, a numerical example is given to demonstrate the feasibility and effectiveness of the proposed results. [ABSTRACT FROM AUTHOR]

This paper investigates the cluster consensus problems of generic linear multi-agent systems with switching topologies. Sufficient criteria for cluster consensus, which generalise the results in existing literatures, are derived for both state feedback and observer-based control schemes. By using an averaging method, it is shown that cluster consensus can be achieved when the union of the acyclic topologies contains a directed spanning tree within each cluster frequently enough. We also provide a principle to construct digraphs with inter-cluster cyclic couplings that promote cluster consensus regardless of the magnitude of inter-agent coupling weights. Finally, numerical examples are given to demonstrate the effectiveness of the proposed approaches. [ABSTRACT FROM AUTHOR]

This paper is concerned with theH∞filtering problem for a class of continuous-time linear switched systems with the asynchronous behaviours, where ‘asynchronous’ means that the switching of the filters to be designed has a lag to the switching of the system modes. By using the Lyapunov-like functions and the average dwell time technique, a sufficient condition is obtained to guarantee the asymptotic stability with a weightedH∞performance index for the filtering error system. Moreover, the results are formulated in the form of linear matrix inequalities that are numerical feasible. As a result, the filter design problem is solved. Finally, an illustrative numerical example is presented to show the effectiveness of the results. [ABSTRACT FROM AUTHOR]

This paper considers the stabilisation of switching nonlinear models by switching between the subsystems. We assume that arbitrary switching between two subsystems is possible once a subsystem has been active for a predefined number of samples. We use a Takagi–Sugeno representation of the models and a switching Lyapunov function is employed to develop sufficient stability conditions. If the conditions are satisfied, we construct a switching law that stabilises the system. The application of the conditions is illustrated in several examples. [ABSTRACT FROM AUTHOR]

This paper studies robust stability of positive switched systems (PSSs) with polytopic uncertainties in both discrete-time and continuous-time contexts. By using multiple linear copositive Lyapunov functions, a sufficient condition for stability of PSSs with dwell time is addressed. Being different from time-invariant multiple linear copositive Lyapunov functions, the Lyapunov functions constructed in this paper are time-varying during the dwell time and time-invariant afterwards. Then, robust stability of PSSs with polytopic uncertainties is solved. All conditions are solvable via linear programming. Finally, illustrative examples are given to demonstrate the validity of the proposed results. [ABSTRACT FROM PUBLISHER]

This paper studies practical output tracking of switched nonlinear systems inp-normal form. No solvability of the practical output tracking problem for subsystems is required. A constructive scheme to solve the problem for a switched nonlinear system is set up by exploiting the single Lyapunov function method and the tool of adding a power integrator. Also, we design a proper switching law and construct state-feedback controllers of subsystems. A two inverted pendulums as a practical example, which cannot be handled by the existing approaches, illustrates our theoretical result. [ABSTRACT FROM PUBLISHER]

The output regulation problem of switched linear multi-agent systems with stabilisable and unstabilisable subsystems is investigated in this paper. A sufficient condition for the solvability of the problem is given. Owing to the characteristics of switched multi-agent systems, even if each agent has its own dwell time, the multi-agent systems, if viewed as an overall switched system, may not have a dwell time. To overcome this difficulty, we present a new approach, called an agent-dependent average dwell time method. Due to the limited information exchange between agents, a distributed dynamic observer network for agents is provided. Further, a distributed dynamic controller based on observer is designed. Finally, simulation results show the effectiveness of the proposed solutions. [ABSTRACT FROM PUBLISHER]

Many actual engineering applications can be modelled as large-scale switched system, while switching behaviours often occur in some short finite time intervals; thus, it is significant to ensure the finite-time boundedness of large-scale switched system in practical terms. In this paper, the problems of finite-time stability analysis and stabilisation for large-scale switched system are addressed. First, considering different switching signals for subsystems, the concepts of decentralised finite-time boundedness (DFTB) and decentralised finite-timeH∞controllers are introduced, which focus on the dynamical transient behaviour of large-scale switched system during finite intervals. Under these concepts, several sufficient conditions are given to ensure a class of large-scale systems decentralised finite-time stable based on the decentralised average dwell times, and then the results are extended toH∞finite-time boundedness of large-scale switched system. Finally, based on the results on DFTB, optimal decentralisedH∞controllers and average dwell times are designed under the minimum value ofH∞performance. Numerical examples are given to illustrate the effectiveness of the proposed approaches in this paper. [ABSTRACT FROM AUTHOR]

Consensus problem of high-order integral multi-agent systems under switching directed topology is considered in this study. Depending on whether the agent’s full state is available or not, two distributed protocols are proposed to ensure that states of all agents can be convergent to a same stationary value. In the proposed protocols, the gain vector associated with the agent’s (estimated) state and the gain vector associated with the relative (estimated) states between agents are designed in a sophisticated way. By this particular design, the high-order integral multi-agent system can be transformed into a first-order integral multi-agent system. Also, the convergence of the transformed first-order integral agent’s state indicates the convergence of the original high-order integral agent’s state, if and only if all roots of the polynomial, whose coefficients are the entries of the gain vector associated with the relative (estimated) states between agents, are in the open left-half complex plane. Therefore, many analysis techniques in the first-order integral multi-agent system can be directly borrowed to solve the problems in the high-order integral multi-agent system. Due to this property, it is proved that to reach a consensus, the switching directed topology of multi-agent system is only required to be ‘uniformly jointly quasi-strongly connected’, which seems the mildest connectivity condition in the literature. In addition, the consensus problem of discrete-time high-order integral multi-agent systems is studied. The corresponding consensus protocol and performance analysis are presented. Finally, three simulation examples are provided to show the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

In this paper, we focus on the consensus problem for leaderless and leader–followers multi-agent systems with periodically intermittent control. The dynamics of each agent in the system is a linear system, and the interconnection topology among the agents is assumed to be switching. We assume that each agent can only share the outputs with its neighbours. Therefore, a class of distributed intermittent observer-based consensus protocols are proposed for each agent. First, in order to solve this problem, a parameter-dependent common Lyapunov function is constructed. Using this function, we prove that all agents can access a prescribed value, under the designed intermittent controller and observer, if there are suitable conditions on communication. Second, based on the investigation of the leader-following consensus problem, we design a new distributed intermittent observer-based protocol for each following agent. Finally, we provide an illustrative example to verify the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

This paper is concerned with a continuous-time and infinite-horizon optimal stopping problem in switching diffusion models. In contrast to the assumption commonly made in the literature that the regime-switching is modeled by an independent Markov chain, we consider in this paper the case of state-dependent regime-switching. The Hamilton–Jacobi–Bellman (HJB) equation associated with the optimal stopping problem is given by a system of coupled variational inequalities. By means of the dynamic programming (DP) principle, we prove that the value function is the unique viscosity solution of the HJB system. As an interesting application in mathematical finance, we examine the problem of pricing perpetual American put options with state-dependent regime-switching. A numerical procedure is developed based on the DP approach and an efficient discrete tree approximation of the continuous asset price process. Numerical results are reported. [ABSTRACT FROM AUTHOR]

The accurate mathematical model of converter is very important in the process of designing high performance switch power. Nonlinear, multimodal and time-varying are the characteristics of the DC-DC converter. So it is necessary to study it in a new way. This paper presents a mathematical model of Boost converter circuit by state space average method. The closed-loop PI controller based on the Boost converter model was designed. The static and dynamic performance of the closed-loop system was tested in Simulink which demonstrated a good behavior of the system to meet the requirements of user. [ABSTRACT FROM AUTHOR]

This paper addresses the global adaptive stabilisation via switching and learning strategies for a class of uncertain nonlinear systems. Remarkably, the systems in question simultaneously have unknown control directions, unknown input disturbance and unknown growth rate, which makes the problem in question challenging to solve and essentially different from those in the existing literature. To solve the problem, an adaptive scheme via switching and learning is proposed by skilfully integrating the techniques of backstepping design, adaptive learning and adaptive switching. One key point in the design scheme is the introduction of the learning mechanism, in order to compensate the unknown input disturbance, and the other one is the design of the switching mechanism, through tuning the design parameters online to deal with the unknown control directions, unknown bound and period of input disturbance and unknown growth rate. The designed controller guarantees that all the signals of the resulting closed-loop systems are bounded, and furthermore, the closed-loop system states globally converge to zero. [ABSTRACT FROM AUTHOR]

This paper deals with the design of anti-windup compensator for discrete-time switched systems subject to input saturation. The cases of static and dynamic anti-windup controllers are addressed aiming at maximising the estimate of the basin of attraction of the origin for the closed-loop system. Two aspects of the switching law are taken into account during the design: either it is arbitrary or it is a part of the complete control law. Theoretical conditions allowing to synthesise the anti-windup compensator are mainly described through linear matrix inequalities. Computational oriented conditions are then provided to solve convex optimisation problems that are able to give a constructive solution. [ABSTRACT FROM AUTHOR]

This article describes a novel resonant gate driver for charging the gate capacitor of power metal-oxide semiconductor field-effect-transistors (MOSFETs) that operate at a high switching frequency in power converters. The proposed resonant gate driver is designed with three small MOSFETs to build up the inductor current in addition to an inductor for temporary energy storage. The proposed resonant gate driver recovers the CV2gate loss, which is the largest loss dissipated in the gate resistance in conventional gate drivers. In addition, the switching loss is reduced at the instants of turn on and turn off in the power MOSFETs of power converters by using the proposed gate driver. Mathematical analyses of the total loss appearing in the gate driver circuit and the switching loss reduction in the power switch of power converters are discussed. Finally, the proposed resonant gate driver is verified with experimental results at a switching frequency of 1 MHz. [ABSTRACT FROM AUTHOR]

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In this study, a new design method and efficient designs for radix-radders are proposed for carbon nanotube field effect transistor (CNFET) FET nanotechnology. This application also investigates the capability of the nanoscale device for designing high-performance analogue circuits. The proposed designs benefit from the unique electrical properties of CNFET, such as near-ideal current voltage characteristics, very high transconductance, high-performance switches and very high-performance and high-gain binary inverters, at nanoscale. Moreover, adjustable threshold voltage and the same mobility of electrons and holes in a CNFET facilitate the design and modification procedures. The proposed design can be considered as an instance of a general adder, capable of adding radix-rdigits with high precision. It is noteworthy that a very limited number of carbon nanotube diameters for designing the proposed adder are needed, which enhance the manufacturability. The proposed circuits are designed based on arithmetic relations and are also verified at 32 nm feature size using HSPICE and the Stanford standard SPICE model. [ABSTRACT FROM PUBLISHER]

In an effort to reduce switching and gate-drive losses in power converters when the energy density is increased by increasing the switching frequency, various resonant gate drivers (RGDs) based on a current source have been proposed to drive metal–oxide–semiconductor field-effect transistors in low-voltage high-current power converters. The resonant gate drivers enable high efficiency owing to energy recovery and the reduction of switching losses. Recently, many studies have been performed on the design of new topologies and loss analyses. Despite numerous proposed studies on RGDs, a comparative study based on a theoretical analysis has not been carried out. In this paper, a theoretical loss analysis in terms of the conduction, switching and gate-drive losses is presented according to the operation stages. In particular, the conduction loss has been expressed in terms of a general loss model that can generally applied to all topologies. Five RGD topologies are evaluated for their efficiency performance with analytical expressions and features based on several operating conditions. [ABSTRACT FROM PUBLISHER]

Lead zirconate titanate (PZT) ceramics have been extensively used for electronic applications due to their ability to couple mechanical and electrical energy, a so-called piezoelectric effect. This effect is caused by the shift of Ti4+or Zr4+ion relative to neighbouring atoms. The movement of the ions due to an external load causes reorientation of the ferroelectric polarization. Microscopically, the detail of the shift of Ti ion, reflecting polarization switching behaviour, can be analyzed by X-ray absorption near-edge structure (XANES) technique. The aim of this project is to investigate the shift of Ti4+ion in PZT under the application of electric field by in-situ X-ray absorption technique. For this project, the special custom-built high voltage sample chamber installed at synchrotron XANES beam line at Synchrotron Light Research Institute, Thailand, was employed to conduct the experiment. XANES spectrum of bulk PZT was collected under the different amplitudes of an applied electric field. Ti K-edge X-ray absorption spectra were analyzed by IFEFFIT software package. The results showed that the pattern of XANES changed with the alternation of the applied field amplitude. The change of XANES spectrum was caused by the movement of Ti4+ion reflecting the change of ferroelectric polarization. From the analysis, it was found that this technique could be used to investigate the Ti4+ion shifting of PZT bulk ceramics. [ABSTRACT FROM AUTHOR]

We propose a slot-width switching (SWS) silicon–organic hybrid waveguide for broadband and efficient wavelength conversion. By switching the slot width of different lengths, the quasi-phase-matching can be obtained. Compared with width-modulated silicon-on-insulator (SOI) waveguide, the non-linear absorption can be ignored in slot waveguide which is filled with p-toluene sulphonate. Consequently, the conversion efficiency at a particular signal wavelength is improved, and the 3-dB conversion bandwidth is also extended. The numerical simulation results indicate that, for a continuous-wave pump at 1550 nm, a conversion bandwidth of 570 nm and a peak conversion efficiency of 11.32 dB can be realized in a 7.5-mm-long SWS waveguide, which is better than that of width-modulated SOI waveguide. [ABSTRACT FROM AUTHOR]

In this paper, we discuss the interval consensus problem of multi-agent systems by providing a special Laplacian of directed graphs. As one of the most important issues in the coordination control of multi-agent systems, the consensus problem requires that the output of several spatially distributed agents reach a common value that depends on the states of all agents. For the given consensus protocol and initial states, a fixed consensus value is obtained. The resulting consensus value, however, may not be ideal or meet the quality that we require from the multi-agent system. In this paper, by introducing two state-dependent switching parameters into the consensus protocol, the system given by the proposed protocol can globally asymptotically converge to a designated point on a special closed and bounded interval. In other words, the system given by the proposed protocol can globally asymptotically reach interval consensus and then the system can also achieve a generalised interval average consensus if the directed graph is balanced. Simulations are presented to demonstrate the effectiveness of our theoretical results. [ABSTRACT FROM PUBLISHER]

The simultaneous effect of disturbance and imprint on the polarization switching behaviors of ferroelectric poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) thin films has been investigated. The results show that the switching characteristics are affected obviously by the imprint as well as the disturbing process. The switching characteristics are well analyzed using the “single read-dual integration” pulse protocol. It is found that the decrease of M-value (“M-value” model is defined as the differences between a switching and a non-switching polarization) with disturb is much faster than that of the pure imprint both before and after fatigue. This result is useful for the design of the related ferroelectric devices. [ABSTRACT FROM AUTHOR]

In this work, switching characteristics of poly(vinylidene fluoride-trifluoroethylene) (P(VDF-TrFE)) copolymer films are investigated over wide ranges of thickness. It is found that the thickness dependence of the coercive field is in accordance with the classical crystallization model. The leakage current shows a higher value of 140nC/cm2as the thickness of P(VDF-TrFE) film is reduced to 50 nm. In addition, an electroactive interlayer has been employed to improve the ferroelectric properties of P(VDF-TrFE) film. After more than 106cycles of switching, the cell still has good polarization performance at both 25 and 60°C even as the thickness of P(VDF-TrFE) film is down to 50 nm. [ABSTRACT FROM AUTHOR]

Switching function optimization for minimum source harmonic injection for a static VAR compensator is presented. The static VAR compensator is configured with a fixed capacitor and insulated-gate bipolar transistor controlled reactor. The switching function is optimized for minimum source harmonic injection considering the desired fundamental voltage across load terminals. A gravitational search algorithm is employed for this purpose. It is observed that the proposed switching scheme with two different switching angles per half-cycle provides lower source harmonic injection compared to conventional switching, hence improving the source current harmonics. The switching angles are computed off-line using the gravitational search algorithm for varying modulation indices considering the minimum total harmonic distortion of the reactor voltage. The switching angles are stored in a processor as a function of the modulation index for on-line application using a piecewise mixed model approximation technique for low memory usage. It is observed that the proposed switching improves the source current total harmonic distortion on an average of 4 to 5% over most of the operating range compared to conventional switching without optimization. Various simulation and experimental results are presented on different loads to validate the proposed concept. [ABSTRACT FROM PUBLISHER]