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In order to verify the feasibility of replacing silver layer with cold sprayed copper coating on the static electrical contact surface of high voltage switch，an electronic universal testing machine was used to apply certain pressure on the test samples with surface treatments of silver plating and cold sprayed copper coating，and the contact resistance of such samples was measured by micro-resistance tester，the influence of different surface treatments on the contact resistance of samples was analyzed，and then the temperature rise test of conductors with two different surface treatments was carried out on 252 kV GIL prototype.Results showed that the contact resistance of electrical contact surface with cold sprayed copper coating was lower，and the temperature rise value obtained from the temperature rise test was also lower than that of silver plated electric contact surface，indicating that the cold sprayed copper coating can replace the silver plating treatment on the electrostatic contact surface and reduce the manufacturing cost of high-voltage switch.

To deal with the attacks employing unknown security vulnerabilities or backdoors which are difficult for traditional defense techniques to eliminate,mimic security defense (MSD) that employs “dynamic,heterogeneity,redundancy (DHR)” mechanism can increase the difficulty and cost of attack and uncertainty of system so as to improve network security.Based on the software defined networking (SDN),an implementation architecture of MSD was proposed.First,diverse functional equivalent variants for the protected target were constructed,then leverage the rich programmability and flexibility of SDN to realize the dynamic scheduling and decision-making functions on SDN controller.Simulation and experimental results prove the availability and the intrusion tolerant ability of the architecture.

When fault arises in the rolling bearing it usually takes on cyclical characteristics. Firstly, the desired source signal is extracted coarsely and the weight separation matrix ... is obtained by the proposed algorithm using the estimated fundamental period of the desired fault signal. Then, the fixed-point algorithm is applied to the observed signals using ... as its initial weight matrix and more accurate desired source signal is derived. The proposed method has the following advantages over the constrained independent component analysis (CICA) : it neither need to estimate the fundamental period τ of the desired source accurately nor need to construct the reference signal precisely which is otherwise for the CICA method. Besides, the proposed method has a higher accuracy over the recent BSE methods. At last, the above stated advantages of the proposed method are verified through simulation and the fault diagnosis test of rolling bearings. [ABSTRACT FROM AUTHOR]

Dynamic tracking (DT) is a kind of dynamic positioning (DP) in a broad sense, and it is often employed to enable the ship to reach its required position within a limited time. In this paper, main interest is placed on research achievements of DT. Both full-actuated ships and under-actuated ships are elaborated in respects of theoretical method, numerical simulation and experimental validation, etc. Unlike DP system, the motion equations of DT must be still nonlinear. Meanwhile, added mass, Coriolis and centripetal forces, nonlinear damping and the disturbances due to wind, current and wave etc. should also be considered. Being complex, nonlinear control system can be designed by methods from backstepping to adaptive backstepping, full state feedback, output feedback, sliding mode control and neural network control with performance of DT becoming better and better. In general, Lyapunov stability theory is used to study the control stability of the DT. This paper is beneficial to further study of DT. [ABSTRACT FROM AUTHOR]

This paper designs a post-disaster relief robot system. The system is divided into a remote monitoring control station and a robotic body. The robotic body is equipped with sophisticated sensor systems, motion control planning system, real-time communications and reliable actuators etc, and mounted night vision CCD camera with 512 X 582 resolution. Real-time images are obtained by pyroelectric infrared detection module which detects human radiation energy, and looks upon rescue personnel. An automatic obstacle avoidance device is designed to prevent the robot collision. Remote monitor control station is equipped with the corresponding management software. Through the transmission of image, the station real-time remote controls the robot, observes and analyzes image information, gets the position of the second accident -prone, such that rescue efficiency and safety are improved. Robotic system data and image information are transmitted through a wireless way, which has small size, fast response, practical usage, and it has a broad market prospect. [ABSTRACT FROM AUTHOR]

Objective: To study the effects of amiloride, an inhibitor of urokinase, on pathological and pathophysiological changes of chronic obstructive pulmonary disease (COPD) model, and to investigate the role of urokinase plasminogen activator system components in the pathogenesis of COPD., Methods: Healthy Wistar rats (n = 24) were randomly divided into a control group, a model group and an amiloride group. After 7 weeks, lung function measurements were performed. The total and different white blood cell counts of bronchoalveolar lavage fluid (BALF) were determined, and collagen deposition of lung sections was observed by picrosirius staining. The expressions of u-PA, u-PAR and PAI-1 in bronchial lung tissues were examined by immunohistochemical analysis., Results: In the model group the expiratory resistance (Re) was significantly higher than that of the control group and the amiloride group, while forced expiratory volume in the 0.3 s/forced expiratory capacity (FEV(0.3)/FVC%) and peak expiratory flow (PEF) were significantly lower than those of the other two groups. Significant increase in total white blood cells and percentage of neutrophils and macrophages in BALF was found in the model group as compared to the control group and the amiloride group. The collagen deposition, mainly type I collagen, in airway walls was significantly increased in the model group. The levels of u-PA, u-PAR and PAI-1 in the model group [(0.166 +/- 0.010), (0.158 +/- 0.024), (0.171 +/- 0.012), respectively] were significantly higher than those in the control group [(0.137 +/- 0.015), (0.122 +/- 0.009), (0.144 +/- 0.005), respectively] and the amiloride group [(0.126 +/- 0.004), (0.120 +/- 0.010), (0.122 +/- 0.004), respectively]. F values were 32.463, 4.094, 79.562 respectively, and all P < 0.001. Moreover, u-PAR protein level was positively correlated with neutrophils in BALF in the model group (r = 0.754, P = 0.031)., Conclusion: Administration of u-PA inhibitor-amiloride significantly alleviated airway inflammation and the pathological changes in COPD rats, suggesting that the u-PA system components are key mediators regulating the inflammatory reaction and tissue remodeling in the pathological process of COPD.

Objective: To observe the changes of tumor necrosis factor alpha (TNF alpha), interleukin 8 (IL-8) in liver ischemia/reperfusion injury and the protective effect of hydrophilic Salvia monomer MP-1 on them., Methods: Hypothermic hypoxia reoxygenation model of human liver sinusoidal endothelial cell line and ischemia/reperfusion model of isolated rat liver were used. TNF alpha and IL-8 were measured with ELISA kits. Cell injury was excluded by trypan blue stain, sinusoidal endothelial cell function was assessed by hyaluronic acid uptake rate through RIA. Liver function was assayed by alanine transaminase (ALT), aspartate aminotransferase (AST) and lactate dehydrogenase (LDH) release as well as output of bile flow., Results: During hypoxia reoxygenation, sinusoidal endothelial cell injury, TNF alpha and IL-8 increased significantly in time-dependent manner, while sinusoidal cell function decreased. Cell injury was positively correlated to the released amount of TNF alpha (r = 0.949, P < 0.05) and IL-8 (r = 0.892, P < 0.05), respectively, the mortality could be reduced within 6 hrs by adding anti-TNF alpha monoclonal antibody and increased by treating with recombinant human TNF alpha. Function of isolated rat liver lowered alone the increasing of low temperature ischemia/reperfusion time. MP-1 could markedly lower the mortality of endothelial cells and TNF alpha and IL-8 release, it also could alleviate ischemia/reperfusion injury to isolated rat liver., Conclusion: TNF alpha participated in liver ischemia/reperfusion injury directly, and MP-1 might alleviate the injury through inhibiting TNF alpha and IL-8.