Current Issue : January - March Volume : 2016 Issue Number : 1 Articles : 6 Articles
The growing complexity of optimization problems in distributed systems (DSs) has motivated computer scientists to strive for\nefficient approaches. This paper presents a novel cooperative algorithm inspired by chaosââ?¬â??order transition in a chaotic ant swarm\n(CAS). This work analyzes the basic dynamic characteristics of a DS in light of a networked multi agent system at microlevel\nand models a mapping from state set to self-organization mechanism set under the guide of system theory at macro level. A\ncollaborative optimization algorithm (COA) inDS based on the chaosââ?¬â??order transition of CAS is then devised. To verify the validity\nof the proposed model and algorithm, we solve a locality-based task allocation in a networked multi agent system that uses COA.\nSimulations show that our algorithm is feasible and effective compared with previous task allocation approaches, thereby illustrating\nthat our design ideas are correct....
Due to the well condition and the un-expected imbalance movement of the pumping unit in use,\nthe energy consumes a lot. The existing balancing equipment cannot adjust and monitor the pumping\nunits in real time. Therefore this paper introduces the new adaptive balancing equipmentââ?¬â?\nfan-shaped adaptive balancing intelligent device, projects a design of such control system based\non PLC, and determines the principle of the control system, the execution software and the design\nflow. Site commissioning effect on Daqing Oilfield shows this fan-shaped adaptive balancing intelligent\ndevice can effectively adjust and monitor the pumping unit in real time, the balance even\nadjusts from 0.787 to 0.901, and integrated energy saving rate is 14.2%. It is approved that this\ncontrol device is professionally designed, with strong compatibility, and high reliability....
This paper focuses on the enforcement of nonlinear constraints in Petri nets. An integer linear programming model is formulated\nto transform a nonlinear constraint to a minimal number of conjunctive linear constraints that have the same admissible marking\nspace as the nonlinear one does in Petri nets. The obtained linear constraints can be easily enforced to be satisfied by a set of control\nplaces with a place invariant based method.Thecontrol places make up a supervisor that can enforce the given nonlinear constraint.\nFor a case that the admissible marking space decided by a nonlinear constraint is nonconvex, another integer linear programming\nmodel is developed to obtain a minimal number of constraints whose disjunctions are equivalent to the nonlinear constraint with\nrespect to the reachable markings. Finally, a number of examples are provided to demonstrate the proposed approach....
This paper deals with the problems of ââ?¬Å?explosion of term,ââ?¬Â uncertain parameter in static synchronous compensator (STATCOM)\nsystem with nonlinear time-delay. An improved adaptive controller is proposed to enhance the transient stability of system states\nand reduce computational complexity of STATCOM control system. In contrast to backstepping control scheme in high order\nsystems, the problem of ââ?¬Å?explosion of termââ?¬Â is avoided by designing dynamic surface controller. The low pass filter is included\nto allow a design where the model is not differentiated and thus has prevented the mathematical complexities effectively. In\naddition, unlike the traditional adaptive control schemes, the certainty equivalence principle is not required for estimating the\nuncertain parameter by system immersion and manifold invariant (I&I) adaptive control. A smooth function is added to ensure\nthat the estimation error converges to zero in finite time.The effectiveness of the proposed controller is verified by the simulations.\nCompared with adaptive backstepping and proportion integration differentiation (PID), the oscillation amplitudes of transient\nresponse are reduced by nearly half, and the time of reaching steady state is shortened by at least 11%....
Therobust adaptive exponential synchronization problem of stochastic chaotic systemswith structural perturbations is investigated\nin mean square. The stochastic disturbances are assumed to be Brownian motions that act on the slave system and the normbounded\nuncertainties exist in all parameters after decoupling. The stochastic disturbances could reflect more realistic dynamical\nbehaviors of the coupled chaotic system presented within a noisy environment. By using a combination of the Lyapunov functional\nmethod, the robust analysis tool, the stochastic analysis techniques, and adaptive control laws,we derive several sufficient conditions\nthat ensure the coupled chaotic systems to be robustly exponentially synchronized in the mean square for all admissible parameter\nuncertainties. This approach cannot only make the outputs of both master and slave systems reach ...
SCADA (Supervisory Control and Data Acquisition) is concerned with gathering process information\nfrom industrial control processes found in utilities such as power grids, water networks,\ntransportation, manufacturing, etc., to provide the human operators with the required real-time\naccess to industrial processes to be monitored and controlled either locally (on-site)or remotely\n(i.e., through Internet). Conventional solutions such as custom SCADA packages, custom communication\nprotocols, and centralized architectures are no longer appropriate for engineering this\ntype of systems because of their highly distribution and their uncertain continuously changing\nworking environments. Multi-agent systems (MAS) appeared as a new architectural style for engineering\ncomplex and highly dynamic applications such as SCADA systems. In this paper, we propose\nan approach for simply developing flexible and interoperable SCADA systems based on the\nintegration of MAS and OPC process protocol. The proposed SCADA system has the following advantages:\n1) simple (easier to be implemented); 2) flexible (able to adapt to its environment dynamic\nchanges); and 3) interoperable (relative to the underlying control systems, which belongs\nto diverse of vendors). The applicability of the proposed approach is demonstrated by a real case\nstudy example carried out in a paper mill....
Loading....