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Computerized interlocking systems have been studied for many years. Available interlocking systems mainly are centralized control systems. The great progress of distributed control technology and intelligent terminals make it possible to develop distributed interlocking system. To standardize operations of devices in distributed railway signaling system, this article takes the process of train entering...
The main contribution of this paper is to present a new stability criterion of a kind of uncertain systems with time-varying delay. While the system matrices endure segment uncertainty, we show that there is an extreme criterion for the asymptotic stability of the given systems. Such result make it possible to check several vertex conditions. It is proved that, under our assumption, the interval system...
This paper addresses the H∞ control problem for networked control systems (NCSs) over multiple communication channels. A new method on the H∞ controller design is proposed to reduce the negative influences of communication constraints including signal transmission delay, data packet dropout and quantization effect. The proof techniques rely on Lyapunov function and linear matrix inequality (LMI) tools...
In the actual power system three-phase voltages are distorted and asymmetric and contain a large number of negative sequence components. Traditional ip-iq method which detect harmonic currents based on instantaneous reactive power theory will be inaccurate, so the positive sequence voltage component of A-phase need be extracted. Improved instantaneous symmetrical components structured a rotary phases...
There are two major factors restricting current loop bandwidth, switching frequency and digital delay. Digital delay includes A/D sampling time and PWM duty cycle update. The calculating delay is the major source of delay in the loop. The bandwidth expansion strategy was proposed. Double stator current sampling and double PWM duty cycle update were achieved in a carrier period. This paper chooses...
This paper addresses the H∞ control problem for linear systems where sensors, controllers and plants are connected by a network medium. A novel control scheme is proposed to stabilize an unstable plant by employing a time-varying sampling period method. Furthermore, the method may also compensate packet dropout and network-induced delays. The simulation results illustrate the effectiveness of the...
On the basis of robust H∞ control, the output feedback controller is presented for a class of dynamic time-varying delay network systems. The objective of designing robust H∞ controller is to achieve the desired queue size and to guarantee the asymptotic stability of the close-loop. The sufficient condition for the existence of a dynamic output feedback controller is presented via matrix inequalities...
In ongoing efforts to reduce the congestion of the airspace and the cost of company, optimization stands as a fundamental research problem. This paper proposes a new method by establishing a SIMMOD simulate model and a controller workload objective function to address the dynamic slot-route assignment problem of the air traffic. Genetic Algorithms was used that offers a dynamic optimization required...
The vehicle control system based on Network communication becomes increasingly complicated recently. The traditional research only focuses on the improvement of network communication quality or system control performance. The network configuration had been carried out to study the vehicle chassis integrated control system. Based on the MATLAB/Simulink and TrueTime Toolbox, the distributed CAN network...
This paper is devoted to study the problem of a partially dependent predator-prey model with time delay. The effect of delay on the stability of the interior positive equilibrium is investigated, and the conditions for existence of Hopf bifurcations are given. Finally, numerical simulations are carried out to illustrate our analytical results, the largest Lyapunov exponent is computed, and the chaotic...
In this paper, one studies the existence and uniqueness of almost periodic mild solutions to fractional delayed differential equations of the form Dtα x(t) = Ax(t) + Dtα-1 f(t, xt) where 1 <; α <; 2, A: D(A) ⊂ X → X is a linear densely defined operator of sectional type on a complex Banach space X and f: R × X → X is jointly continuous. Let f(t, x) be almost periodic in t ∈ R uniformly for x...
This report presents a technique of chaotification based on the optimal time-delay feedback that can make a system chaotic with large chaotic parameters range. The bifurcation analysis is done to determine the stability of the time-delay system. An implicit performance index and an optimization strategy are proposed for the time-delay control scheme that can be effectively carried out to obtain the...
To improve the efficiency and the topology mismatch problem of P2P overlay network, a new method of topology construction, CLSP2P, was introduced. The topology construction of CLSP2P not only consideration the physical location of nodes, but also consideration the semantic information of nodes: Nodes in CLSP2P were first organized as autonomous domain based on their physical location, then the nodes...
This paper presents a new data transmission protocol in Delay Tolerant Mobile Wireless Sensor Networks, which divides the data transmission process into two phases: data reception phase and data forwarding phase, mainly fulfilling through analyzing the state of mobile nodes and using Hand up mechanism. Simulation result shows that, through the implementation of two phases, we can obtain a higher message...
In present paper, the time-delayed feedback is coupled with a ratio-dependent predator-prey model of Holling □ type. This predator-prey system can be seen as a human-controlled biological system. Regarding the delay as parameter, we investigate the existence of local Hopf bifurcations. By using the Hassard method and the center manifold argument, we derive the explicit formulas determining the stability,...
Contention-based forwarding (CBF) has proven to achieve a good performance in routing in mobile and vehicular ad hoc networks. CBF's main advantage is that it does not require the knowledge about the local neighborhood, eliminating, therefore, the periodic beacon exchange that causes degradation in the network performance, especially when the density of the neighborhood is high. On the other hand,...
In wireless communication system, power saving mechanism is a key issue since a mobile station operates depending on limited power. Hence, the IEEE 802.16e system provides three types of power saving classes (PSC I, PSC II and PSC III) for the mobile station (MS) to reduce power consumption. Many models have been made to analyze the performance of power saving mechanism (PSM) of the IEEE 802.16e system...
Cognitive radio (CR) technology has been considered promising to enhance spectrum efficiency via opportunistic transmission at link level. To make CR useful, networking CRs to form a cognitive radio network (CRN) is able to support end-to-end transmission from CR source to CR destination. However, the opportunistic nature of CR link for interference avoidance to primary users degrades the quality-of-service...
In this paper, the results of outdoor-to-indoor multiple-input multiple-output (MIMO) channel measurements at 780 MHz are presented. The motivation for these measurements was to provide actual measurement data needed to extend the International Mobile Telecommunications -Advanced (IMT-A) channel models to the frequencies around 400 - 900 MHz. There are publications reporting measurement results for...
In wireless mesh networks, scheduling is the bottleneck of the cross-layer design approach. Thus, it is surprising that CSMA is utility-optimal if it is used traffic-adaptive. However, the price to pay is short-term fairness and thus end-to-end delay. In this paper, we propose a step size adaptation algorithm that combines the advantages of small and large step sizes in a way that the convergence...
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