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Projective synchronization investigates the synchronization of systems evolve in same orientation, however, in practice, the situation of same orientation is only minority, and the majority is different orientation. This paper investigates the latter, proposes the concept of rotating synchronization, and verifies its necessity and feasibility via theoretical analysis and numerical simulations. Three conclusions were elicited: first, in three-dimensional space, two arbitrary nonlinear chaotic systems who evolve in different orientation can realize synchronization at end; second, projective synchronization is a special case of rotating synchronization, so, the application fields of rotating synchronization is more broadly than that of the former; third, the overall evolving information can be reflected by single state variable's evolving, it has self-similarity, this is the same as the basic idea of phase space reconstruction method, it indicates that we got the same result from different approach, so, our method and the phase space reconstruction method are verified each other.

Projective synchronization between two nonlinear systems with different dimension was investigated. The controllers were designed when the dimension of drive system greater than the one of response system. The opposite situation also was discussed. In addition, we found an approach to control the chaotic (hyperchaotic) system to exhibit the behaviors of hyperchaotic (chaotic) system. The numerical simulations were implemented on different chaotic (hyperchaotic) systems, and the results indicate that our methods are effective.

The solar energy conversion driven by the solar sensor (or the so-called solar cell) has become an important and feasible way to solve global energy crisis while at the same time minimizing environmental pollution. The solar charge controller is the key of its active system for the signal processing circuits involved. In this paper, a fully integrated solar charge controller is presented. The charger has wide input voltage range about 10–28 V for the solar-powered panel. The input loop regulation is used here as the maximum power point tracking protection. This charger also provides different kinds of battery voltages about 4–12 V. The controller system uses just one error amplifier (EA) and no external compensation components is needed. Besides, this controller has 600-kHz pulse-width modulation (PWM) and offers the over-current/over-voltage protection. Other components like bandgap, reference generator, saw-tooth generator, register controller and driver circuits are all implemented in this circuit. This chip is fabricated in a 0.4-μm 5 V/40 V 2P4M process. The power consumption of this full-integrated solar charge controller IC is about 10 mA.

Refining and petrochemical processing facilities utilize various process control applications to raise productivity and enhance plant operation. Client–server communication model is used for integrating these highly interacting applications across multiple network layers utilized in distributed control systems. This paper presents an optimum process control environment by merging sequential and regulatory control, advanced regulatory control, multivariable control, unit-based process control, and plant-wide advanced process control into a single collaborative automation platform to ensure optimum operation of processing equipment for achieving maximum yield of all manufacturing facilities. The main control module is replaced by a standard real-time server. The input/output racks are physically and logically decoupled from the controller by converting them into distributed autonomous process interface systems. Real-time data distribution service middleware is used for providing seamless cross-vendor interoperable communication among all process control applications and distributed autonomous process interface systems. Detailed performance analysis was conducted to evaluate the average communication latency and aggregate messaging capacity among process control applications and distributed autonomous process interface systems. The overall performance results confirm the viability of the new proposal as the basis for designing an optimal collaborative automation platform to handle all process control applications. It also does not impose any inherent limit on the aggregate data messaging capacity, making it suitable for scalable automation platforms.

Oil and gas processing facilities utilize various process automation systems with proprietary controllers. As the systems age; older technologies become obsolete resulting in frequent premature capital investments to sustain their operation.

This paper presents a new design of automation controller to provide inherent mechanisms for upgrades and/or partial replacement of any obsolete components without obligation for a complete system replacement throughout the expected life cycle of the processing facilities.

The input/output racks are physically and logically decoupled from the controller by converting them into distributed autonomous process interface systems. The proprietary input/output communication between the conventional controller CPU and the associated input/output racks is replaced with standard real-time data distribution service middleware for providing seamless cross-vendor interoperable communication between the controller and the distributed autonomous process interface systems. The objective of this change is to allow flexibility of supply for all controller’s subcomponents from multiple vendors to safeguard against premature automation obsolescence challenges.

Detailed performance analysis was conducted to evaluate the viability of using the standard real-time data distribution service middleware technology in the design of automation controller to replace the proprietary input/output communication. The key simulation measurements to demonstrate its performance sustainability while growing in controller’s size based on the number of input/output signals are communication latency, variation in packets delays, and communication throughput. The overall performance results confirm the viability of the new proposal as the basis for designing cost effective evergreen process automation solutions that would result in optimum total cost of ownership capital investment throughout the systems’ life span. The only limiting factor is the selected network infrastructure.

Multi-level Inverters (MLIs) are increasingly employed in grid-connected Photovoltaic (PV) systems to optimize power quality. The use of MLIs offers several benefits over traditional inverters, including improved output waveform quality, reduced Total Harmonic Distortion (THD) and increased efficiency. However, the control of MLI is complex, and a precise control system is required to ensure that the system operates at optimal conditions. Therefore, an Adaptive Chaotic Mapping Philippine Eagle Optimization (ACM-PEO) algorithm-based Three degrees of freedom Fractional Order Proportional Integral Derivative with Dual Filter (3DOF-FOPID²-DF) controller is proposed. The dual derivative and dual filter component introduced in the 3DOF-FOPID controller improve the transient response of the system even under sudden load changes. The ACM-PEO algorithm further enhances the system performance of the 3DOF-FOPID²-DF controller by optimizing the parameter gains. The proposed ACM-PEO-based 3DOF-FOPID²-DF control technique is simulated in MATLAB and the simulation results demonstrate that it has improved transient and dynamic response, reduced THD, faster convergence and better tracking of the reference signal. These benefits enhance the efficiency and reliability of the systems.

In this paper, we discuss in detail the local stability, Hopf bifurcation and pitchfork bifurcation of an inertial two-neuron system with time delays by applying the second-order approximation approach and analyzing the associated transcendental equation, respectively. Comparison has been made between the two methods. Numerical results have been presented to verify the analytical predictions. Specially, numerical examples show the time-varying control and the impulsive control which can both improve the stability of the system effectively.

In this paper, the methods to rapidly deploy closed-loop control systems are presented. A flexible real-time embedded platform based on reconfigurable computing technologies is established, on which control blocks consisting of optimized control algorithms are set up. By employing control blocks, a set of tools aiming to shorten the development cycle of embedded control systems are developed. Compare to conventional ways, the tools give controller developers much faster ways to construct required controllers with higher flexibility.

A microcontroller-based control system is a direct outgrowth of the extensive advances in the Integrated Circuit design and microelectronic device processing technology. This has led to the development of new forms of technologies. This paper presents a technique of microcontroller based control system for controlling the lights of a room. Using the technique, according to the intensity of the sunlight in a room, the states of light of that room will change. Therefore we need to collect data or information from the environment using light sensors to control lights. The microcontroller collects the information from the atmosphere and changes the state of different lights. The analog data collected by the sensors are converted to digital form by an Analog to Digital Converter (ADC) and then fed to the microcontroller. The output data stream of the microcontroller is in digital form by which analog device lights will be controlled.

The analog fuzzy intelligent controllers for autonomous mobile robot to avoid static and dynamic obstacles in its local environment are presented. The controller designed for the robot is reconfigurable in nature in terms of number of rules in database i.e. flexibility for online rule change as per the frequency of obstacle in the local environment. The controller is proposed with adjustable membership function in terms of shape and degree of overlapping with dynamic rule base. New accurate MAX and MIN circuits are introduced. The controller is simulated using Tanner^® tool. The two-input single-output fuzzy controller with 25 rules is implemented in 0.25µm CMOS technology. The maximum delay was found to be 9.915ns for the processing of 25 rules and the value of FLIPS was found to be 100.85 MFLIPS.

Present-day computer systems have drastically transformed from the ones in days of basic file sharing, peripheral sharing or the hosting of companywide applications on a server to much more sophisticated, small and faster systems. These systems have further expanded to include cloud-based networks, virtualized desktops, servers, etc. The capabilities of evolving heterogeneous computer systems require advanced control plane. Software-defined networking (SDN) proposes to control the network from a centralized controller instead of a distributed configuration. SDN makes it easier for network operators to evolve network capabilities. Even though SDN proposes a logically centralized system, the controllers may not represent a single, centralized device, instead the control plane may consist of logically centralized but physically distributed controllers wherein each controller manages different administrative domains of the network or different parts of the flow space. There are mainly two types of control plane architecture: flat control plane and hierarchical control plane. In this paper, we have analyzed the reliability and availability of the hierarchical SDN control plane. We take into consideration work-load capacities of the controllers, link failures, node failures and controller-end failures to determine the reliability of the system.

This paper presents a design and model of a powered elbow exoskeleton to assist the movement of elbow joint. This exoskeleton will strengthen the elbow joint by providing a controllable torque in addition to that generated by elbow joint muscles. Therefore, it can be used for healthy people and for physically weak people, such as disabled or elderly people, in performing their daily activities. The proposed design focuses on using EMG signals recorded from biceps and triceps muscles (which are responsible for elbow joint movements) to control the exoskeleton in performing elbow flexion/extension. The EMG signals and elbow flexion angle were recorded from four healthy subjects whilst performing different tasks of elbow flexion/extension. Pre-processing and conditioning of EMG signals were performed by system hardware while MATLAB/Simulink was used for further signal processing and for designing the whole system of arm and exoskeleton. EMG signals from biceps and triceps muscles were used as reference inputs to the model giving the intended motion. In the design, the parameters of the components, such as the DC motor, gear box and conditioning circuits, were taken from available (off the shelf) cheap components to make it easy and cheap to implement the proposed exoskeleton. In addition, all the torques: the forearm and exoskeleton torques and the torque generated by the muscles, were taken into consideration in the design for being as close as possible to the practice. Future work will be to develop a prototype to implement the proposed design.

Software Defined Network (SDN) decouples the control plane from the data plane, yielding a vast flexibility for networks. This paper focuses on the optimal placement for heterogeneous controllers. First, SDN networks are modeled using graph theory. Therefore, the controller placement problem is transformed into a specified graph partitioning problem. Then, an optimal controller placement scheme is proposed based on multi-level graph partitioning. Finally, Simulation experiments are conducted on real network topologies. The results indicate that our scheme can achieve nearly optimal controller load balance and is of application value to wide-area SDN deployments.

This paper introduces the PID controller based on the human simulation intelligent control algorithm and analyzes the human simulation intelligent PID control algorithm in the MATLAB simulation environment for comparison with the traditional PID control algorithm. An intelligent PID controller is designed through the simplification of the intelligent PID algorithm into a program run in single-ship. It is has improved control effects and is adaptable to standard serial communication protocol, with characteristics of cheap production and simple configuration.

The AT89C51 microcontroller is regarded as the control center in intelligent alarm system for fire, and the system can receive and take a treatment on the concentration and temperature signal of smoke output by the fire detector with sound-light alarm. It can monitor the temperature and smoke concentration, etc. by sending inspection signal to the site continually, and have a feedback to alarm controller constantly. The controller compares the accepted signal with the normal value in storage to judge and determine whether there is a fire. When the smoke and temperature in site are anomalies, or fire occurs, it can realize sound-light alarm, the set of alarm limit of smoke concentration and temperature, self-diagnosis breakdown, delayed alarm, etc., which has a certain practical value.