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The purpose of this paper is to show the existence results for adapted solutions of infinite horizon doubly reflected backward stochastic differential equations with jumps. These results are applied to get the existence of an optimal impulse control strategy for an infinite horizon impulse control problem.

The main methods used to achieve the objectives of this paper are the properties of the Snell envelope which reduce the problem of impulse control to the existence of a pair of right continuous left limited processes. Some numerical results are provided to show the main results.

In this paper, the authors found the existence of a couple of processes via the notion of doubly reflected backward stochastic differential equation to prove the existence of an optimal strategy which maximizes the expected profit of a firm in an infinite horizon problem with jumps.

In this paper, the authors found new tools in stochastic analysis. They extend to the infinite horizon case the results of doubly reflected backward stochastic differential equations with jumps. Then the authors prove the existence of processes using Envelope Snell to find an optimal strategy of our control problem.

This paper aims to analyze transient and steady state processes in series resistive capacitive-circuits when the supplied voltage is a sequence of periodic rectangular pulses. The purpose is to obtain an analytical formula for the capacitor voltage at any instant of time, both for the transient and the steady-state processes.

The main approach is to use a combination of differential and recurrence equations.

An analytical expression (formula) for obtaining the capacitor voltage at any instant of time has been found.

The results obtained are new. They are much more convenient to use than the results obtained by the Fourier series. The exposed approach can also be used in other circuits and other forms of the supplied voltage.

The working hypothesis, on which this paper is built, is that it is advantageous to look at protocols of robot rehabilitation in the general context of human-robot interaction in haptic dyads. The purpose of this paper is to propose a new method to detect and evaluate an index of active participation (AC index), underlying the performance of robot-assisted movements. This is important for avoiding the slacking phenomenon that affects robot therapy.

The evaluation of the AC index is based on a novel technique of assistance which does not use constant or elastic forces but trains of small force impulses, with amplitude adapted to the level of impairment and a frequency of 2 Hz, which is suggested by recent results in the field of intermittent motor control. A preliminary feasibility test of the proposed method was carried out during a haptic reaching task in the absence of visual feedback, for a group of five stroke patients and an equal group of healthy subjects.

The AC index appears to be stable and sensitive to training in both populations of subjects.

The main original element of this study is the proposal of the new AC index of voluntary control associated with the new method of pulsed haptic interaction.

Orbital maneuver of the spacecraft can cause large-amplitude vibration of its flexible solar array, which leads to large dynamic stress and a risk of structural failure and fatigue failure. This paper aims to provide a method to reduce such vibration.

Through controlling the rotation at the root of the solar array, a method of vibration reduction is proposed using zero-placement input shaping technique. Experimental research on a beam scale model of the solar array is performed to verify the effectiveness of the method. Simulation of a detailed example is carried out to investigate whether the method can be applied in engineering.

The experimental results demonstrate the effectiveness of such method. The simulation results indicate that, by adopting the presented method, the vibration induced by orbital maneuver can be diminished remarkably.

Studies on the robustness of the method are left for further work. Additionally, since only the first-order bending vibration of the flexible solar array is eliminated, further improvements are required such that the stated method can be applied to suppress multi-mode vibration.

An effective method is proposed for spacecraft designers planning to actively suppress the vibration of flexible solar array during the process of orbital maneuver.

This paper fulfils a source of theoretical and experimental studies for orbital maneuver system design and offers practical help for spacecraft designers.

Purpose – To present the argument that the paradigm of spontaneously self-ordering open adaptation is common to Hayek's thesis on the mind (The Sensory Order) and to his presentations of social science (the social order).

Methodology/approach – To show how Hayek's methodological stance for social science interrelates with his theoretical work in neuroscience and psychology, where the ‘connectionist’ paradigm is relevant to extensive writings upon the human condition.

Findings – •close parallels across biological, psychological and social adaptations give a basis for determining which methods are appropriate to gain knowledge about knowledge;•broad confirmation is evident that methods of proven worth to physical science have little relevance for the analysis of psychological and social phenomena, which are more complex than the phenomena of the material world.

Research limitations/implications – •that the social order rests upon common beliefs;•that no simple distinction separates subjective and objective knowledge;•that any drive for social science to match the precision of physical science is misguided;•that in seeking an objective focus, behaviourism eliminates crucial introspective insights upon motivation and goals.

Originality/value of paper – The presentation is one of exegesis showing the relevance of Hayek's seminal work in theoretical psychology to the broadest themes of human understanding and social adaptation.

The model for digitally controlled three-phase pulse width modulation (PWM) boost rectifiers is a sampled data model, which is different from the continuous time domain models presented in previous studies. The controller, which is tuned according to the model in continuous time domain and discretized by approximation methods, may exhibit some unpredictable performances and even result in unstable systems under some extreme situations. Consequently, a small-signal discrete-time model of digitally controlled three-phase PWM boost rectifier is required. The purpose of this paper is to provide a simple but accurate small-signal discrete-time model of digital controlled three-phase PWM boost rectifier, which explains the effect of the sampling period, modulator and time delays on system dynamic and improves the control performance.

Based on the Laplace domain analysis and the waveforms of up-down-count modulator, the small signal model of digital pulse width modulation (DPWM) in the Laplace domain is presented. With a combination of state-space average and a discrete-time modeling technique, a simplified large signal discrete time model is developed. With rotation transformation and feed-forward decoupling, the large-signal model is decoupled into a single input single output system with rotation transformation. Then, an integrated small signal model in the Laplace domain is constructed that included the time delay and modulation effect. Implementing the modified z-transform, a small-signal discrete-time model is derived from the integrated small signal model.

In a digital control system, besides the circuit parameters, the location of pole of open-loop transfer function is also related to system sampling time, affecting the system stability, and the time delay determines the location of the zero of open-loop transfer function, affecting the system dynamic. In addition to the circuit parameters discussed in previous literature, the right half plane (RHP) zero is also determined by the sampling period and the time delay. Furthermore, the corner frequency of the RHP zero is mainly determined by the sampling period.

The model developed in this paper, accounting for the effect of the sampling period, modulator and time delays on the system dynamic, give a sufficient insight into the behavior of the digitally controlled three-phase PWM rectifier. It can also explain the effect of sampling period and control delay time on system dynamic, accurately predict the system stability boundary and determine the oscillation frequency of the current loop in critical stable. The experimental results verify that the model is a simple and accurate control-oriented small-signal discrete-time model for the digitally controlled three-phase PWM boost rectifier.

The two‐dimensional discrete Huygens’ modelling or TLM simulation is presented for the TE electromagnetic field problems. The TLM element or node with variable traveling speed and characteristic impedance is applied to several practical problems including scattering at the edge of a wall and over periodic grids or grooves, wave propagation along a dielectric structure, and a mode coupling between two parallel optical waveguides. The TLM solutions are compared with the theoretical ones or the results of other numerical methods and reasonable agreement is achieved.

The purpose of this paper is to investigate the vibration suppression of industrial track robot and propose a practical solution.

Root‐cause analysis through dynamic modeling, and vibration suppression using the acceleration smoother.

The vibration is due to insufficient damping based on the model analysis. The solution achieved significant performance improvement without redesign of robot hardware and controller.

The design of the proposed acceleration smoother is still empirical based, which is unable to achieve optimal design.

This solution is very easy to implement. It is robust, reliable and is able to generate consistent results.

A very practical industrial solution, especially useful for upgrading the existing systems in the field without redesign the hardware and controller.

Based on the analysis of the data of the landscape live performances which have already been performed, this paper combs the development process of the live performances and other information of the performance types so that the public can have a clearer and clearer understanding of the live performances. Through time-frequency domain analysis method, the characteristic elements of waveform music are extracted and classified into sub-music segments in different rough emotional domains according to certain classification methods. And the application weights of the feature values of each music feature are defined in different emotion domains, which makes the input of the system more rational. For the output of the light action control data, this article has a certain interpretation of the DMX512 data, making the interpretation of the output more intuitive. The basic characteristics of music include speed, mode, beat, tone, volume, and the pitch, pitch, and length of notes. Therefore, in the future, the method of realizing music visualization in architectural lighting design and the method of realizing interaction with people will have more possibilities.