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A distributed H ∞ filtering issue is addressed in this paper for discrete-time nonlinear systems in the face of replay attacks over sensor networks, where an indicator variable is introduced to describe whether a replay attack is launched by the adversaries. First, an interesting pattern dependent on three parameters including a time-varying one is established to account for the temporal behavior of malicious attacks. Then, taking advantage of such a model, the resulting filter dynamic is transformed into a switching system with a subsystem with time-varying delays. By means of the famous switching system theory, a sufficient condition guaranteeing the H ∞ performance is derived to disclose the tolerant attack condition, that is, the attack-active duration and proportion. In addition, the applicable filter gains are achieved with the aid of the solutions of matrix inequalities. Finally, an example is purposively given to adequately illustrate the availability of the developed secure filtering strategy. [ABSTRACT FROM AUTHOR]

In this work, we propose a context-aware switching of routing protocol scheme for specific application requirements of IoT in real-time using a softwaredefined networking controller in wireless sensor networks. The work planned has two stages i) Selection of suitable routing protocol (RP) for given IoT applications using higher cognitive process and ii) Deployment of the corresponding routing protocol. We use the supervised learning-regression method for classification of the routing protocol while considering the network parameters like stability, path delay, energy utilization, and throughput. The chosen routing protocol will be set in the sensor network using a software-defined networking controller in an exceedingly flexible manner during the second stage. Extensive simulation has been done and results are evaluated to point out the strength of the proposed work, while dynamically varying the specific requirements of IoT applications. We observe that the work proposed is path-breaking the prevailing methods, where a specific routing protocol is employed throughout the period of time. It's clearly shown that the proposed, Low-cost Context-Aware Protocol Switching (LCAPS) scheme is efficient in improving the performance of the sensor network and also meets the specific application requirements of IoT by using Software-Defined Wireless Sensor Networks SDWSNs. [ABSTRACT FROM AUTHOR]

This paper investigates the switching control issue for uncertain vehicle suspension systems, meanwhile, actuator failure is taken into account. Takagi-Sugeno (T-S) fuzzy model is utilized to describe the considered uncertain suspension systems. Consider that most existing analysis results related to suspension systems are independent of membership functions, which may cause conservatism, thus, a novel membership functions-dependent Lyapunov function is employed in the stability analysis. In the proposed analysis technique, both of the information of membership functions and their derivatives are applied to reduce the conservativeness. A switching control strategy is proposed to assure that suspension constraint requirements are satisfied by using the information of time-derivative of membership. Lastly, a simulation example is shown to identify the availability of the approach put forward in this paper. [ABSTRACT FROM AUTHOR]

Abstract In this paper, we propose a new time-switching relaying (TSR) protocol for multi-destination dual-hop underlay cognitive radio relay networks with simultaneous wireless information and power transfer (SWIPT) technique. The proposed protocol maintains the same receiver complexity of the conventional TSR protocol with the ability for implementing both of them using the same hardware. We study the performance of the proposed TSR protocol and compare it with the conventional TSR and power-splitting relaying (PSR) protocols. Unified analytical expression is derived for the outage probability, in addition to studying the performance at high signal-to-noise ratio (SNR) values where unified approximate and simple expressions for the outage probability are provided. The results show that the proposed TSR protocol outperforms the conventional TSR protocol in terms of outage probability. Also, findings illustrate that applying the SWIPT technique in multi-destination underlay cognitive relay networks results in a unity diversity order. In contrast to conventional relaying networks, results show that the best location for the relay node in SWIPT relay networks is either near the source or the destinations, but not in between. [ABSTRACT FROM AUTHOR]

Flower pollination algorithm (FPA) is a new swarm intelligence optimization algorithm which simulates flower pollination. For all intelligent optimization algorithms, the performance analysis of parameters can affect the convergence speed, convergence precision and global optimization ability. In this paper, an enhanced variation of flower pollination algorithm (MFPA) was proposed. The convergence speed and algorithm searching precision are determined by the switching probability andƛin Levy flight. The simulation experiments are carried out by using the six typical test functions to discuss this influence. The simulation results show that the switching probability is less sensitive to the MPFA algorithm. With reasonable setting of MFPA parameters, the search precision and convergence speed can be improved effectively. [ABSTRACT FROM AUTHOR]

Concerned with descriptor systems, this paper extends recent results on nonquadratic controller design. The proposal employs an exact Takagi-Sugeno model of the descriptor redundancy form and a fully nonquadratic Lyapunov function. Based on these elements, a switching control law is proposed that achieves stabilization up to the modelling area by feeding back the time derivatives of the membership functions: these are obtained from a Levant’s robust differentiator. Conditions thus obtained turned up to be linear matrix inequalities. Via suitable examples, the methodology is shown to outperform previous approaches on the subject. [ABSTRACT FROM AUTHOR]

This paper is concerned with the H∞ filtering problem for switched Takagi-Sugeno (T-S) fuzzy systems with asynchronous switching, where “asynchronous” means that the switching of the filters has a lag to the switching of system models. In the switched T-S fuzzy systems, every subsystem is represented by the well-known T-S fuzzy model. Using the multiple Lyapunov functions approach and mode-dependent average dwell time technique, a sufficient condition is developed to ensure the filtering error system to be globally uniformly asymptotically stable with a weighted H∞ performance index. Moreover, the desired asynchronous H∞ filters can be constructed by solving a set of linear matrix inequalities. Finally, an example about the continuous stirred tank reactor is provided to demonstrate the applicability of the obtained results. [ABSTRACT FROM AUTHOR]

This paper investigates the mixed H ∞ and passive filtering problem for switched Takagi-Sugeno (T-S) fuzzy systems with average dwell time (ADT) in both continuous-time and discrete-time contexts. To deal with this problem, a new performance index is proposed for switched systems. This new performance index can be viewed as the mixed weighted H ∞ and passivity performance index. Based on this new performance index, the weighted H ∞ filtering problem and the passive filtering problem for switched T-S fuzzy systems can be solved in a unified framework. Combining the multiple Lyapunov functions approach with a matrix decoupling technique, new sufficient conditions for the existence of mixed weighted H ∞ and passive filters are obtained for switched T-S fuzzy systems. All these conditions are expressed in terms of linear matrix inequalities (LMIs). The desired filters can be constructed by solving these LMIs. Finally, numerical examples and practical examples are provided. [ABSTRACT FROM AUTHOR]

The paper provides relaxed designs of fault estimation observer for nonlinear dynamical plants in the Takagi–Sugeno form. Compared with previous theoretical achievements, a modified version of fuzzy fault estimation observer is implemented with the aid of the so-called maximum-priority-based switching law. Given each activated switching status, the appropriate group of designed matrices can be provided so as to explore certain key properties of the considered plants by means of introducing a set of matrix-valued variables. Owing to the reason that more abundant information of the considered plants can be updated in due course and effectively exploited for each time instant, the conservatism of the obtained result is less than previous theoretical achievements and thus the main defect of those existing methods can be overcome to some extent in practice. Finally, comparative simulation studies on the classical nonlinear truck-trailer model are given to certify the benefits of the theoretic achievement which is obtained in our study. [ABSTRACT FROM AUTHOR]

This paper is concerned with the problem of finite-time control for a class of interconnected impulsive switched systems with neutral delay in which the time-varying delay appears in both the state and the state derivative. The concepts of finite-time boundedness and finite-time stability are respectively extended to interconnected impulsive switched systems with neutral delay for the first time. By applying the average dwell time method, sufficient conditions are first derived to cope with the problem of finite-time boundedness and finite-time stability for interconnected impulsive switched systems with neutral delay. In addition, the purpose of finite-time resilient decentralized control is to construct a resilient decentralized state-feedback controller such that the closed-loop system is finite-time bounded and finite-time stable. All the conditions are formulated in terms of linear matrix inequalities to ensure finite-time boundedness and finite-time stability of the given system. Finally, an example is presented to illustrate the effectiveness of the proposed approach. [ABSTRACT FROM AUTHOR]

This paper studies the dynamic behavior of a piezoelectric micro-lens actuator driven by a feedback system. The feedback system consists of the actuator in the forward path and an optical displacement sensor and a 90 o phase shifter multiplied by a gain as feedback elements. The piezo-electric micro-lens actuator is fabricated and characterized for its dynamic performance by varying the feedback gain. The results show that the settling time and quality factor of the actuator are reduced by a factor of more than 100 and 10 dB, respectively when the gain is increased from 0 to 0.0134. The micro-lens actuator demonstrated switching time of 2.5ms at a resonance frequency of 750 Hz without affecting its static deflection characteristic. This is significantly fast in comparison to other reported switching times for micro-lens actuator. [ABSTRACT FROM AUTHOR]

We present a monolithic CMOS biosensor system comprised of a switch-matrix-based array of carbon nanotube field-effect transistors (CNT-FETs) and an associated readout circuitry. The switch-matrix allows for flexible selection and simultaneous routing of 96 sensor elements to the readout channels. The resistances of the CNT-FETs were measured by applying a constant voltage and measuring the resulting current. Variation of the first-stage-amplifier gain and bandwidth allows for measuring resistances in the range between 50 kΩ and 20 MΩ at a bandwidth of up to 20 kHz. A parallel integration of the CNT-FETs has been achieved by using a floating electrode dielectrophoresis (DEP) manipulation technique. [ABSTRACT FROM AUTHOR]

This paper investigates the problems of actuator fault estimation and accommodation for discrete-time switched systems with state delay. By using reduced-order observer method and switched Lyapunov function technique, a fault estimation algorithm is achieved for the discrete-time switched system with actuator fault and state delay. Then based on the obtained online fault estimation information, a switched dynamic output feedback controller is employed to compensate for the effect of faults by stabilizing the closed-loop systems. Finally, an example is proposed to illustrate the obtained results. [ABSTRACT FROM AUTHOR]

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The decision about spending time on an activity, switching to the next activity and transport mode used to travel to the next activity location depends on money value of time; opportunity cost of time at activity. Optimal condition of transition between two activities occurs when their marginal utility of time is equal. The presented framework in this paper models the marginal utility of activity to express the money benefit earned by spending each unit of time at the given activity. The proposed model is generalized for the schedule with any number of activities as contrast to previous studies, where such models were used for schedules with fixed number of activities. This framework can be used to calculate the loss in value of time due decreased activity participation resulting from travel delays. [ABSTRACT FROM AUTHOR]

The principle of operation, its practical realization and measurement research of a reconfigured system of a signal conditioner are presented. A two-sourced conditioner supplied by direct current with four resistance sensors and four switching keys was experimentally tested. In the example application the resistance of sensors in the function of the same point load, caused by perpendicular force, was measured. In order to compare the results achieved with the use of a conditioning circuit, similar tests were carried out for a four-channel Wheatstone's bridge-based commercial acquisition card. The research aimed at confirming the possibility of implementing the constructed signal conditioner in cheap measurement equipment. [ABSTRACT FROM AUTHOR]

The article contains evaluation of effect of different winding switching methods for synchronous motor with permanent magnet excitation (SMPM) on energetic efficiency, possibility of enlarging the ranges of working speeds and torques, adaptation of regulating characteristics with the aim of using it in particular electric drive. The evaluation is performed at similar values of relative speed and relative inductance. The conditions, which make sensible the usage of 120-degree or 180-degree switching, meanwhile all considered SMPM characteristics are not worse than those under vector control, are defined. It is proved, that there is a possibility to minimize engine's energy consumption by regulating switching angle, as well as change it's mechanical characteristics. In particular, it is possible to get mechanical SMPM characteristic, typical for direct-current motor with series excitation, suitable for usage in electric traction drive. [ABSTRACT FROM AUTHOR]

This paper addresses the fault detection problem of switched systems with servo inputs and sensor stuck faults. The attention is focused on designing a switching law and its associated fault detection filters (FDFs). The proposed switching law uses only the current states of FDFs, which guarantees the residuals are sensitive to the servo inputs with known frequency ranges in faulty cases and robust against them in fault-free case. Thus, the arbitrarily small sensor stuck faults, including outage faults can be detected in finite-frequency domain. The levels of sensitivity and robustness are measured in terms of the finite-frequency H − index and l 2 -gain. Finally, the switching law and FDFs are obtained by the solution of a convex optimization problem. [ABSTRACT FROM AUTHOR]

This paper considers a three-dimensional trajectory design problem for horizontal well. The problem is formulated as an optimal control problem of switched systems with continuous state inequality constraints. Since the complexity of such constraints and the switching instants is unknown, it is difficult to solve the problem by standard optimization techniques. To overcome the difficulty, by a time-scaling transformation, a smoothing technique and a penalty function method, an efficient computational method is proposed for solving this problem. Convergence results show that, for a sufficiently large penalty parameter, any local optimal solution of the approximate problem is also a local optimal solution of the original problem. Two numerical examples are presented to illustrate the efficiency of the approach proposed. [ABSTRACT FROM AUTHOR]

This paper investigates the consensus seeking problem of mobile sensor networks (MSNs) with random switching topologies. The network communication topologies are composed of a set of directed graphs (or digraph ) with a spanning tree. The switching of topologies is governed by a Markov chain. The consensus seeking problem is addressed by introducing a global topology-aware linear quadratic (LQ) cost as the performance measure. By state transformation, the consensus problem is transformed to the stabilization of a Markovian jump system with guaranteed cost. A sufficient condition for global mean-square consensus is derived in the context of stochastic stability analysis of Markovian jump systems. A computational algorithm is given to synchronously calculate both the sub-optimal consensus controller gains and the sub-minimum upper bound of the cost. The effectiveness of the proposed design method is illustrated by three numerical examples. [ABSTRACT FROM AUTHOR]

A PV-integrated utility grid environment using steepest ascent maximum power point tracking algorithm for PV system and an adaptive finite time fast terminal sliding mode (FTFTSM) controller-based voltage source converter (VSC) is proposed in this study. The interfacing VSC in between PV system and grid is subjected to an I-V-based control approach, where control output variables are depending on current at PCC and PV side VSC voltage. During solar insolation, the active power is injected from PV to local load and grid, whereas the load reactive power compensation is being taken care of by the utility grid. The proposed adaptive FTFTSM control strategy is implemented for the VSC to ensure a fast error tracking capability with finite convergence time. Moreover, the adaptive nature of the proposed sliding mode control provides more robustness, less sluggish fault recovery compared with ordinary terminal sliding control and conventional PI control. The comprehensive numerical model is demonstrated in MATLAB script environment with various power system disturbances like changes in solar insolation, changes in local load, converter parametric changes, and faults on the converter and inverter buses, and partial shading condition of the PV array. The simulation of proposed system is being carried out in MATLAB/SIMULINK environment to validate the control scheme. A detailed switched model verification is also elaborated on EMTDC/PSCAD platform. [ABSTRACT FROM AUTHOR]

This paper describes research into a novel control strategy of traction converter for the AC-Trolley Line with the middle frequency transformer (MFT). Attention is paid to the problematics of finding a suitable control algorithm that will provide minimal magnetic saturation. This could be ensured by variable pulse widths, determined according to the actual value of input voltage. Special attention is focused on the single-phase matrix converter topology and the best commutation solution. Two basic methods of controlling the switches in the matrix converter are discussed. The first method requires some knowledge of the converter output current polarity and the second method assumes some knowledge of the input voltage polarity. In addition, the article describes the switching method in uncertain states - when the voltage or current cross zero. Moreover, the paper presents a new modular topology with several separate middle frequency transformers. The proposed algorithm is described and implemented in the laboratory model. [ABSTRACT FROM AUTHOR]

Catastrophe theory (Thom, 1972, 1993) is the study of the many ways in which continuous changes in a system's parameters can result in discontinuous changes in 1 or several outcome variables of interest. Catastrophe theory--inspired models have been used to represent a variety of change phenomena in the realm of social and behavioral sciences. Despite their promise, widespread applications of catastrophe models have been impeded, in part, by difficulties in performing model fitting and model comparison procedures. We propose a new modeling framework for testing 1 kind of catastrophe model--the cusp catastrophe model--as a mixture structural equation model (MSEM) when cross-sectional data are available; or alternatively, as an MSEM with regime-switching (MSEM-RS) when longitudinal panel data are available. The proposed models and the advantages offered by this alternative modeling framework are illustrated using 2 empirical examples and a simulation study. [ABSTRACT FROM AUTHOR]

The paper deals with a methodology of switching latency measurement in switched Ethernet networks. The switching latency is parameter necessary for simulation and design of low-latency networks that are often intended for real-time control inherent to many industrial applications. The proposed measurement methodology provides a simple way of switching the latency determination and vendor quoted latency values verification directly at the physical layer. Numerous experimental measurements were carried out to support the arguments in this paper and to demonstrate the usability of the proposed methodology. All results are presented and analysed up to 10GBase-R Ethernet including OpenFlow switches. [ABSTRACT FROM AUTHOR]

The estimation of losses plays a key role in the process of building any electrical machine. How to estimate those losses while designing any machine; by obtaining the characteristic of the electrical steel from the catalogue and calculate the losses. However, this way is inaccurate since the electrical steel performs several manufacturing processes during the process of building any machine, which affects directly the magnetic property of the electrical steel and accordingly the characteristic of the electrical steel will be affected. That means the B–H curve of the steel that was obtained from the catalogue will be changed. Moreover, during loading and rotating the machine, some important changes occur to the B–H characteristic of the electrical steel such as the stress on the laminated iron. Accordingly, the pre-estimated losses are completely far from the actual losses because they were estimated based on the data of the electrical steel obtained from the catalogue. So in order to estimate the losses precisely significant factors of the manufacturing processes must be included. The paper introduces the systematic estimation of the losses including the effect of one of the manufacturing factors. Similarly, any other manufacturing factor can be included in the pre-designed losses estimations. [ABSTRACT FROM AUTHOR]

In this paper, a novel cascaded transformer multilevel inverter is proposed. The number of the switching devices is reduced in the proposed topology. This topology comprises of a DC source, several single phase low-frequency transformers, two main power switches and some bidirectional switching devices. In this topology, only one bidirectional switch is employed for each transformer. However, in conventional cascaded transformer multilevel inverter, four switching devices are required for each transformer. Therefore, more output voltage levels can be obtained using fewer switching components. Reduction in the number of switching devices which also means reduction in the number of gate drivers results in smaller size and low implementation cost. Switching power losses are also reduced in this topology. Selective harmonic elimination (SHE) technique is applied to the proposed inverter to obtain a high quality output voltage. Simulation and experimental results are also provided to verify the feasibility of the proposed converter. [ABSTRACT FROM AUTHOR]

To increase the utility of switched-reluctance motors (SRMs) in electric vehicles it is required to increase torque per unit volume (torque density) while maintaining low cost and low torque ripple. This paper presents the design of three new control methods for in-wheel axial-flux SRMs that increase torque density using switching angles and optimal current profiles. All three control methods are compared to two reference control methods from the literature. The second method is shown to be superior in terms of the precision of its switching angle calculations to the first, and speed to the third, though the first method produces lower torque ripple, and the third uses a better model of switching dynamics. In addition, both first and second methods reveal improved performance compared to the control methods adopted from the literature. Thus, all three proposed control methods can be used to improve the performance of in-wheel SRMs, but the second method produces the highest torque density. The second method can be used for in-wheel motor applications which need online switching angle calculations that balance the requirements of high torque density and low torque ripple. [ABSTRACT FROM AUTHOR]

This paper deals with a switching robust tracking feedback design for a corona-effect ozone generator. The generator is considered as a switched systems in the presence of bounded model uncertainties as well as external perturbations. Three nonlinear dynamic models under arbitrary switching mechanisms are considered assuming that a sample-switching times are known. The stabilization issue is achieved in the sense of a practical stability. We apply the newly elaborated (extended) version of the conventional attractive ellipsoid method (AEM) for this purpose. The same analysis was efficient to obtain the minimal size of region where the tracking error between the trajectories of the ozone generator and reference states converges. The numerically implementable sufficient conditions for the practical stability of systems are derived based on bilinear matrix inequalities (BMIs). [ABSTRACT FROM AUTHOR]

A new hybrid control method for blood glucose concentration is developed which switches between two operation modes. The effects of meal-induced disturbances on blood glucose concentrations are expected to be more serious than the time-varying behaviour of glucose metabolism during nocturnal phases. Thus, the control method determines insulin impulses (boli) as a manipulated variable during the day and calculates continuous insulin infusion (basal rates) at night. To test the controller-based insulin therapy in vivo, animal trials with diabetic Göttingen minipigs are used as a proxy for human studies. The controller parameters are selected by in silico studies based on mathematical minipig models, and the resulting individualised controllers are experimentally verified. For this, two control performance requirements must be taken into account: blood glucose concentrations below the critical threshold of 50 mg/dl have to be avoided, and blood glucose peaks caused by ingestion of minipig diet have to be quickly counteracted. Results from these animal experiments show that the closed-loop system satisfies both control requirements and improves insulin therapy compared with a standard therapeutic protocol. [ABSTRACT FROM AUTHOR]

Micro precision X-Y stages have several applications in industry ranging from metal machining to positioning of optical instruments. This paper deals with the evaluation of relationship between jerk in micro precision stages and harmonics in voltage of the motor by which the stage is driven and subsequently proposes an algorithm on Arduino Mega micro controller board to reduce the jerk by shaping the velocity profile while varying the microstepping rate in motor voltage. A micro precision stage with a resolution of 1 micron, driven with a bipolar stepper motor drive is used to evaluate the algorithm. A MEMS accelerometer (ADXL 345) is placed rigidly on the stage, and the acceleration at varying speeds is measured and logged in the micro controller. The micro controller sends commands to the motor driver (L6470 driver) for driving the motor using Serial Peripheral interface. The motor driver is configured in microstepping mode. Experiments confirm the fact that there is a strong correlation between jerk in micropositioning stage and motor supply voltage harmonics. A methodology to reduce the jerk has also been facilitated. This involves use of microstepping mode in stepper motor driver with dynamic sliding in microstepping rate. A threshold value of jerk is considered and based on that, the microstepping rate is varied which subsequently reduces voltage harmonics. Reduction in voltage harmonics reduces the jerk in the stage. Maximum jerk reduction of 97.3 % was achieved in the process. [ABSTRACT FROM AUTHOR]

The anti-islanding protection of synchronous generators is typically performed by voltage and frequency relays. However, one of the main issues related to setting these relays is to identify and differentiate the magnitude and frequency variations of an islanding event from other disturbances that may occur along the system, such as severe load switching. By using an artificial neural network (ANN) based approach, it is possible to recognize existent patterns on the distributed generator voltage waveform, which makes possible to obtain an accurate response about islanding events. However, the ANN training process is not so easy, because it involves important issues such as the definition of the ANN architecture, the size of data window, sampling rate, and selection of a representative training set for the studied problem. In this context, this paper discusses the fundamental aspects for training an ANN used for islanding detection of synchronous distributed generators. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we propose a novel routing protocol, PRO, for profile-based routing in pocket switched networks. Differing from previous routing protocols, PRO treats node encounters as periodic patterns and uses them to predict the times of future encounters. Exploiting the regularity of human mobility profiles, PRO achieves fast (low-delivery-latency) and efficient (low-message-overhead) routing in intermittently connected pocket switched networks. PRO is self-learning, completely decentralized, and local to the nodes. Despite being simple, PRO forms a general framework, that can be easily instantiated to solve searching and querying problems in adhoc smartphone networks. We validate the performance of PRO on real world traces and compare its performance with that of previous approaches. [Copyright &y& Elsevier]

The series resonant DC/DC converter with isolation transformer is investigated. When switching frequency of input inverter bridge is above the resonant one a shortening of the naturally half-waves of current through a L-C resonant circuit takes place resulting in a circulating current through the DC supply source reducing a mean value of supply current and also reducing load voltage in respect to the one at normally resonant case. The main relations for the case with strong voltage supply source are obtained and operation regimes at raised switching frequency investigated using a computer modeling. Some conclusions are made for proper calculation of parameters. It is shown that the shape of the resonant circuit current at raised frequency grows to the triangular one and that asks for proper correction of the expressions obtained for sinusoidal case. Applying qZ input link processes quite differ from observed for the strong supply - arise charging of the capacitors of the link by influence of circulating current and this phenomena impedes to reducing of the load voltage. That qZ link does not allow to create proper regulation of load parameters. [ABSTRACT FROM AUTHOR]

Highlights: [•] Hybrid systems. [•] Identification of a switched linear systems. [•] Identification of active mode. [•] Discrete Particle Swarm Optimization (DPSO). [•] Application to: buck–boost converter. [Copyright &y& Elsevier]

This paper introduces the general linear magnetic circuit model of a novel 5-phase segment type switched reluctance motor (ST-SRM) of which rotor cores are embedded in an aluminum block as well as to improve the performance characteristics under simultaneous two-phase (bipolar) excitation of windings. The developed model implements the magneto motor force (mmf) that is necessary to produce short and exclusive magnetic flux paths minimizing the commutation switching and eddy current losses in the laminations. For this purpose, an equivalent magnetic circuit for newly developed ST-SRM and the underlying assumptions are given. The concept of apparent inductance and torque equations of two-phase simultaneously excited ST-SRM is introduced and the effectiveness and deficiencies of the linear model are given. [ABSTRACT FROM AUTHOR]

Abstract: The containment control problem for multi-agent systems with transmission noises is considered. Due to the existence of the noises, a decaying gain function is introduced to attenuate the noises. Both dynamically switching topologies and randomly switching topologies are considered. Sufficient conditions on the communication graph and control gain function are derived to guarantee the mean square containment. Some numerical examples are provided to verify the results. [Copyright &y& Elsevier]

Electromagnetic effects influence the design of power converters switching in MHz frequency region. In these converters, the high switching frequency in combination with sudden changes in current and voltage levels generate higher order harmonics which causes Electro Magnetic Interference (EMI). To study the effects of increased switching frequency on conducted EMI, the harmonics amplitudes are analyzed by increasing the switching frequency of a two wire input half bridge power converter from 1.32 MHz to 3 MHz. In order to suppress the Common Mode (CM) conducted EMI, different possibilities of connecting the Y - capacitor in a two wire universal input half bridge converter are discussed and the conducted EMI is measured and analyzed by connecting the Y - capacitor at different points. The line filters are designed, characterized and implemented in order to suppress conducted EMI. The effects of increased switching frequency on the line filter design are studied by analysing the EMI spectrum of both the converters. The analysis of results indicates that the filter size is reduced by increasing the switching frequency of the power converter. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, the iterative learning control (ILC) is considered for a class of linear discrete-time switched systems with arbitrary switching signals. It is assumed that the switched system is operated during a finite time interval repetitively, and then the first order P-type ILC scheme can be used to achieve perfect tracking over the whole time interval. By the super vector approach, a convergence condition for such ILC systems in the iteration domain can be given. The theoretical analysis is supported by simulations. [Copyright &y& Elsevier]

Abstract: This paper studies adaptive coordination control of Euler-Lagrange (EL) systems with unknown parameters in system dynamics and possible switching topology. By introducing a novel adaptive control architecture, decentralized controllers are developed, which allow for parametric uncertainties. Based upon graph theory, Lyapunov theory and switching control theory, the stability of the proposed algorithms are demonstrated. A distinctive feature of this work is to address the coordination control of EL systems with unknown parameters and switching topology in a unified theoretical framework. It is shown that both static and dynamic coordinations can be reached even when the communication is switching. Simulation results are provided to demonstrate the effectiveness of the obtained results. [Copyright &y& Elsevier]

Abstract: Most of the hybrid wireless sensor networks MAC protocols are based on conventional Carrier Sense Multiple Access (CSMA) wireless protocols. Z-MAC is an efficient hybrid protocol which alternates between CSMA and TDMA. It utilizes CSMA in low channel contention and switch to TDMA mode in high channel contention. In this paper, we show that Z-MAC does not perform well under high traffic load. It also proposes few enhancements to achieve better performance. [Copyright &y& Elsevier]

Highlights: [•] DFT study of the structural, mechanical, and chiroptical properties of n-(phenylazo)-azobenzenes (n =1–10). [•] Photo-switching capability from a “strip”-like conformation (all-trans) to a “spring”-like conformation (all-cis). [•] Good match between the predicted and the experimental geometries. [•] Surprising nexus between the geometrical and elastic parameters and the Golden Ratio. [Copyright &y& Elsevier]