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Smart-card-based user authentication is a significant security mechanism that allows remote users to be granted access to services and resources in distributed computing environments like clouds. In this paper, we revisit two password authentication schemes with smart cards proposed by Mishra et al. and Wu et al. in 2015, respectively. We demonstrate that: (1) Despite being armed with a formal security...
This paper presents a novel circularly polarized (CP) printed antenna with wide bandwidth and wide axial ratio (AR) beamwidth. The presented antenna is realized by bending a linearly polarized dipole into “S” shape with variable line width, which achieves circularly polarized radiation. Key parameters in designing such an “S” antenna are discussed and studied. It is found that this “S” antenna has...
The target of path planning of mobile multi-vehicle system is to find a suitable path from departure to destination in a uncertain environment, by which the multi-vehicle system can pass through the obstacle area safely and free collision during the marching process. In order to ensure the communication and sensor covering between robots on the path, the robots should not disperse excessively. Therefore,...
Common testability design method of simulated modeling, analysis and optimization for launch vehicle is introduced in this paper. The technical difficulties of testability design for launch vehicle are proposed firstly, subsequently the multi-signal model is adopted and the dependence matrix is established based on Warshall algorithm in order to analyze the testability specification for launch vehicle...
Some potential danger, such as robbery, steal, and drug-dealing activity, can be avoided effectively by detecting loitering behavior in advance. In this paper, we propose a loitering detection algorithm by analyzing the trajectory of pedestrian. Firstly, we propose a trajectory extraction method combined with motion estimation and object detection to adapt to the tracking under a static camera scene...
DC voltage control and power distribution are significant requirements for multi-terminal HVDC control system. The common voltage droop control has the drawback of failing to keep the dc voltage at a fixed value if active power is fluctuating, and voltage margin method actually controls dc voltage only by one converter at a time. A novel control strategy-Coordinated DC Voltage Control-is thus proposed...
This paper proposes a novel control strategy-Coordinated DC Voltage Control (CDVC)-to enhance the AC fault ride through capability of Multi-terminal HVDC system. It is able to keep DC voltage constant and distribute power fast and smoothly, independent on line impedance parameters. Combined with this original control strategy, a series of AC fault ride through methods, including voltage reduction,...
Based on a five-terminal HVDC system connected with offshore wind farms, this paper investigates a three-level control strategy for AC fault ride through, including voltage droop, power reduction and DC chopper control, in order to enhance the system ac fault ride through capability. The restrictions of individual control level are respectively investigated before a trigger mechanism of the three-level...
In this paper, a local discontinuous Galerkin(LDG) method is designed for solving the Schrödinger equation with three-order spatial derivatives. Our schemes extend the previous work of Xu and Shu [8] on solving the nonlinear Schrödinger equations on LDG method. The L2 stability of the LDG methods is proved for general solutions. Numerical results are shown to illustrate the accuracy and capability...
In this paper, a local discontinuous Galerkin (LDG) method is is designed for solving the BBM-Burgers equation with four-order spatial derivatives. Our schemes extend the previous work of Xu and Shu [8] solving the nonlinear Schrödinger equations on LDG method. The L2 stability of the LDG methods is proved for general solutions. Numerical results are shown to illustrate the accuracy and capability...
The hot-rolling strip process is a typical complex industrial processes, and the effect of the traditional control strategy is not perfect. Human-simulated intelligent controller, which does not rely on the accurate mathematical model and also has a good control effect for complex industrial system with delay or random disturbance, simulates the brain of experts. This paper has designed a fuzzy human-simulated...
Pulsed Power Supply (PPS) applied in the electromagnetic launch system must have a compact design and high reliability. In this paper, a PPS for electromagnetic launch system has been built up. The main parts in PFU (Pulsed Forming Unit) are energy storage capacitors (8kV/75kJ), pulse-shaping inductor (10µH), pulse thyristor, crowbar diode and a Rogowski coil for current measuring. The energy storage...
As the development of next-generation wireless broadband cellular networks, base station (BS) cooperation has become a promising tool to increase the per-cell spectral efficiency as well as cell-edge user throughput. In this paper, we introduce a new multi-cell cooperation strategy, where each cooperating BS simultaneously serves two co-channel users, one from the cell edge and the other from the...
Since the entry of WTO, SOEs in China are facing more and more competitions from the market. For many researchers considered SOEs to be low in efficiency, reforms have been carried out in the SOEs, though there still are barriers. Some case studies in different countries showed that the power of culture seemed to be minimized when the corporation's real situation was known by most of the staffs. This...
A depth-averaged 2D numerical model is set up to simulate the hydrodynamics and salinity of the Changjiang Estuary with Delft3D-FLOW, which has been well calibrated and validated with the observed data of the tidal level, velocity and salinity of the Changjiang Estuary. The changes of the salinity under the different narrowing schemes in the North Branch of the Changjiang Estuary during a spring tide...
The boosting algorithm which we introduce is a representational ensemble classification methodology. It is well known that the boosting algorithm can improve the accuracy of any given learning algorithm and train the strong classifiers efficiently. A specific embedded hardware is designed for target identification task. This paper also evaluates the performance and implementation issues for the boosting...
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