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The paper introduces a full-open experimental platform for doubly-fed induction generator (DFIG), which based on wind energy conversation system. The paper starts from the working principles of doubly-fed induction generator (DFIG), then the controlling strategies of gird-connection and variable- speed-constant-frequency (VSCF) and maximum-power-point- tracking. The effects of the controlling strategies...
With increasing capacity of converter system, technology of paralleling modular has become a research hot spot in power electronics field. According to the frequency and amplitude of output AC voltage, converter constituted of paralleling modular can be divided into constant voltage constant frequency (CVCF), variable voltage variable frequency (VVVF), variable voltage constant frequency (VVCF). CVCF...
Hybrid cloud computing paradigm has recently be widely advocated, where Software-as-a-Service (SaaS) providers can extend their local services into the public clouds seamlessly. In this way, dynamic user request workload to a SaaS can be elegantly handled with the rented computing capacity in public cloud. However, although a hybrid cloud may save cost compared with the private cloud, it still introduces...
For emergent production interruptions in supply chain affected by disasters, an emergency decision model with multi-objective and multi-constraints for distribution plan is proposed. In this model, two objectives, profit level and shortage cost, are considered by characterizing the performance and demand of satisfaction of decision-makers. According to preferences of decision makers, three rules of...
This paper proposes the software watermarking algorithm based on Chinese remainder theorem, and introduces the authentication center to certify the watermark, to solve the problem that equation re-sorting algorithm are easily attacked by the random re-sequencing technology. The algorithm further disposals the sequence obtained, the selected divisor sequence and the multiple to generate the key, which...
The surge fault is the severe fault of the mine main ventilator. In order to improve the reliability of the surge diagnosis of the mine main ventilator, this paper presents a new surge diagnosis method based on the multi-sensor information fusion. A novel calculating method of the mass function based on the fuzzy set is put forward. According to the characteristics of the surge diagnosis of the mine...
Missing sensor data is a common problem which severely influences the overall performance of today's dataintensive applications. In order to address this important issue, a resilient Extended Kalman Filter is proposed for discrete-time nonlinear stochastic system and measurement equations with sensor failures and random gain perturbations. The failure mechanisms of multiple sensors are assumed to...
In this paper, an optical simulation model of the off-axis parabolic mirror focusing system based on the ray tracing method has been built up. By analyzing the influence of the detuning angle of the incident beam and the off-axis angle of the off-axis parabolic mirror on the energy concentration of short-pulse laser's focal spot, the regularity conclusions are presented. The spatial position offset...
In order to select proper ammunition to attack a certain target, we proposed a new method for ammunition target matching sequencing based on rough set and weighted TOPSIS. After depicting the mechanism of ammunition damage and target anti-damage, the authors constructed the ammunition target matching index system. Rough set theory was applied to reduce index and decide the weights of key index. The...
In recent years, cognitive radio technology (CR) has been proposed to allow unlicensed secondary users (SUs) to opportunistically access the channels unused by primary users. As a result, there is a lot of recent interests on studying cognitive radio cellular networks (CogCells) that can support both PUs and SUs. Due to the limited transmission range of SUs, in this work we consider supporting Multi-hop...
Distributed storage systems store a substantial amount of data and maintain data integrity by storing redundancy in a large number of storage nodes. When storage nodes fail, the lost data should be regenerated on replacement nodes. Regenerating codes minimize the volume of network traffic brought by the regeneration process. However, regenerating codes consume less traffic by requiring a larger number...
Gaussian mixture model (GMM) is one of the most popular methods to estimate the underlying density function. In this paper, a parameter determination method (PSOGMM) for GMM based on particle swarm optimization (PSO) is proposed. PSOGMM optimizes parameters in GMM based on a new error criterion which is derived based on the integrated square error between the true density function and the estimated...
A new method for optimization control problem based on generalized work principle of optimal control principle is presented. The method of estimating mathematical model with the more precise ballistic parameters is obtained. So solution to optimum control of a non-linear system by criterion of generalized activity is introduced. A universal computing method in construction of optimum control MLRS...
This paper analyzed physical process of movement of geosynchronous satellites, amendment of booster and measurement of Earth station, established the mathematical models and their linearization; On this base, it gave mathematical model for Kalman filter. Executed simulation for the given mathematical model on the Simplified actual date, simulation result is: Kalman filter effectively reduce estimation...
A nanopower subthreshold bandgap reference with 30ppm/°C from −30°C to 150°C has been implemented in 0.18µm CMOS. This design is based on weighted ΔVGS and is free of resistors. The major advantage of this design is that with nanopower consumption, the temperature range is extremely wide. To achieve high performance of subthreshold bandgap operating in high temperature (above 80°C), a leakage current...
Three-dimensional unsteady Reynolds averaged incompressible Navier-Stokes equations are used to simulate the aerodynamic performance of a horizontal axis wind turbine. The numerical method that adopted in this paper is proved to be effective to predict horizontal axis wind turbine aerodynamic characteristics by contrasting the numerical results to the wind turbine experimental data. And the curve...
In this paper, we address the issue of tracking moving objects in the video sequence by a bionic system. In such a task, information collection and feature extraction are both the cores and difficulties which need to be of easy extraction and strong robustness to describe the object completely. We, inspired by the compound eye of mantis shrimps, analyze the special mechanism for motion tracking in...
In this paper, the subspace methods for Wiener systems with state space model are considered, in which a general condition for the static nonlinear maps is proposed. By means of differential analysis and Singular Vector Decomposition, the subspace of extended controllability matrix can be obtained, and then All parameter matrices in linear subsystems and nonlinear function can be estimated. In mild...
A novel state dependent control approach for continuous-time nonlinear systems with general performance criteria is presented in this paper. This controller is optimally robust for model uncertainties and resilient against control feedback gain perturbations in achieving general performance criteria to secure quadratic optimality with inherent asymptotic stability property together with quadratic...
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