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This brief studies distributed event-triggered law design of the Nash equilibrium seeking for noncooperative games under strongly connected graphs. Each player is desired to maximize its payoff function by updating its own action based on other players’ actions. An event-triggered law is proposed, and each player estimates all other players’ actions and exchanges the estimated information with their neighbors only when the triggering conditions are satisfied. Theoretical demonstration is presented to verify that the actions and estimates of players all converge to the unique Nash equilibrium under the proposed event-triggered law and Zeno behavior is excluded. Simulations are provided to show the effectiveness of the main results.

As an important entrance for human-robot interaction, the hand gesture recognition based on wireless sensor has received great attention in recent years. By recognizing fine-grained arm movements, remotely deployed collaborative robot could work more accurately to satisfy human demands. Existing approaches mostly use wearable sensors or wireless devices to recognize human movement, which is with strict position requirements. In this paper, we propose a robust gesture recognition method based on double Doppler radars. Specifically, we use two Doppler radars to collect two sources of doppler signal of a gesture. Then 6 types of gestures with different angles between people and the radar were classified by employing an improved dynamic time warping (DTW) algorithm. Furthermore, we demonstrate the practicability of the proposed method by developing a cooperative robot control system and the average recognition accuracy is 96%.

Hemicellulose-based composites have become promising candidates for eco-friendly packaging applications because of their biodegradability and cost-effectiveness. However, the inherently poor mechanical properties of hemicellulose-based composites largely hinder their potential for targeted application. Fortunately, nanocrystalline cellulose (NCC), an eye-catching nanomaterial, may offer opportunities for addressing the above issue due to its outstanding mechanical properties and environmental friendliness. Herein, a comparative study was conducted on the effect of unmodified and cationically modified nanocrystalline cellulose (CNCC) on the overall properties of the as-prepared hemicelluloses (HC)/sorbitol (SB) films. Scanning electron microscopy (SEM) image shows that the addition of CNCC imparted a relatively smooth surface to the obtained HC/SB films in comparison to NCC. Furthermore, CNCC reinforced HC/SB films exhibited improved thermal stability as compared to that with NCC. From rheological behavior evaluation, the presence of NCC, particularly CNCC, had an important effect on thickening HC/SB suspensions. The tensile stress of the composite films with 9% NCC and 9% CNCC was 9.18 and 10.44 MPa, respectively, which was increased by 14 and 30% in comparison to that of pure HC/SB film (8.05 MPa). The marked increase in elastic modulus as a function of the added NCC or CNCC was also identified. This result strongly supports the conclusion that the addition of NCC or CNCC was effective in improving the mechanical properties of HC/SB films.

This paper develops a distributed discrete-time algorithm to seek Nash equilibrium for games under Markovian switching topologies. In the game problem considered in this paper, all players are assumed to use gradient-like descent method to update their own actions based on the estimation of all the other players’ actions with the intention to minimize their cost functions. All players exchange their estimation information with their neighbors at each discrete time instant through some undirected graphs that are Markovian switching. Suppose that the transition probability matrix is specified and the union of all switching topologies is connected, it is shown that the players’ actions can converge to the unique Nash equilibrium in the mean square sense for any initial condition. The convergence result is established by utilizing Lyapunov stability theory for discrete-time stochastic systems.

With the development of the information and communication technologies, demand response (DR) can be realized more easily and considered as one of effective methods to provide regulation services for the power system. Among the flexible loads for DR, thermostatically controlled loads (TCLs) are regarded as one of the most important loads, because of the large share of power consumption and suitable regulation characteristics without impacting customers’ comfort. However, the dispatching potential of TCLs is difficult to be evaluated due to the limitation of measuring equipment. Faced with this issue, this paper proposes a method for evaluating the dispatching potential of TCLs based on the realistic customer electricity data in China. The relationship between the dispatching potential of TCLs and the ambient temperature is obtained. In this way, the system operator can calculate the dispatching potential of TCLs according to the weather forecast. The effectiveness of the proposed model and method is verified in the case studies.

Electrocoagulation (EC) dephosphorization kinetics plays an important role in design and amplification of EC reactors for phosphate removal. However, the existing EC dephosphorization kinetic models including both statistical model and adsorption model, fail to establish a direct law between the electric field characteristics and the dephosphorization process, which limit their efficient applications in practice. In this study, three classic adsorption isotherm models, i.e., Langmuir, Freundlich and Dubinin-Radushkevich model, were compared to describe the phosphorus adsorption in EC reactor. The experimental data is better fitted with Langmuir model than the other two models, indicating that adsorbed molecules are monolayered dispersed. Afterwards, an advanced EC dephosphorization kinetic model is developed by combining Faraday's law with Langmuir model. Laundry wastewater is used to illustrate the effects of current densities, plate spacing and initial phosphorus concentrations on the model parameters. Finally, the relationships among current efficiency, current density, plate spacing, initial concentration are established by using response surface methodology. Our new EC kinetic model successfully describe the phosphorus removal process of laundry wastewater, which might pave the way for the optimal design of EC reactor.

Human behavior recognition is an effective way to realize natural human-computer interactions. Existing wireless sensing enabled gesture recognition technologies require a single person environment or an absolutely fixed position between the device and the user, which is not practical for daily use. In this paper, we present a non-contact radar-based gesture recognition system, named Gesture-Radar, which is able to capture arm gestures with low environmental dependence using a single Doppler radar. Our prototype design of Gesture-Radar is based on the dual channel Doppler information which contains specific Doppler shift and some other information reflected from the user while performing a certain gesture, and concretely we propose a two-stage classification method to identify arm gestures. Experimental result shows while in a single user environment, Gesture-Radar achieves up to 96.4% average classification accuracy for recognizing 5 different kinds of gestures and can work effectively while the distance between the user and the radar is within 3 meters. We also demonstrate that Gesture-Radar can be well adapted to multi-person environments.

With the development of electric market reform, electricity spot market pilot is about to be launched in China. However, facing more complex settlement process in a competing environment, the existing power metering system may not meet the requirements of modern power market. Thus, it is an urgent problem to determine the improvements performances based on the existing power metering system. This paper will focus on this problem and propose suggestions based on the experience of domestic and foreign electricity market. In this paper, electric power metering systems of Australia, Britain and China (Guangdong Province) is firstly studied and presented in five significant aspects, including market participants, market structure, metering point, acquisition cycle and business managements. Then, their commons and differences will be further analysed and compared as reference of Chinese practice. Finally, suggestions of power metering system construction are proposed in China’ electric power market reform.