Applied Mechanics and Materials Vols. 519-520

Abstract: In pipeline leak detection, collected fault signal will inevitably influenced by all kinds of industrial noise, sometimes even the useful signals submerged by the noise, so before data analysis, we shall be carried out in a first filtering processing. According to the theory of virtual instrument, this paper design the Kalman filter in the LabVIEW program module, and the pressure signal the of the test simulation system is collected real-time filtering, to eliminate noise interference and improve signal-to-noise ratio. It also use the signal after being filtered to give an alarm and location of the leakage of oil pipeline. The experimental data shows that Kalman filter is an efficient recursive filter, it can estimate the states of the dynamic system from a series of contains noise measurement. Kalman filter designed can largely improve the alarming reliability and orientation precision of oil pipeline. Applied to the pipeline leakage fault diagnosis, it obtained the expected effect.

Abstract: To strengthen the comprehensive management of water resources and water environment in the Hai Basin, and improve the quality of water environment in Bohai Sea. On the basis of international advanced Evapotranspiration (ET) technology monitored by remote sensing, the GEF Haihe project put forward water management concept of water consumption and applying it in the river basin and key demonstration counties, This paper mainly presented the ET system design supported by remote sensing and GIS technology, and its application on the basin. The system construction includes the ET center construction, ET system development, ET data production, ET application tools development, training and promotion. Currently, it has been applied on the basin water balance analysis, groundwater management, and water management in some provinces and counties. The results indicated that the system was an effective and feasible case, and it can be extended to the similar water scarcity basins.

Abstract: Extrapolation nowcasting of radar echoes is implemented based on reflectivity data and radial velocity data of Doppler weather radars. VAD algorithm is used to retrieve wind fields, which are used as motion vectors to implement the extrapolation for the reflectivity data within 60 mins. Extrapolation nowcasting results of a weather case by the method agree well with the fact according to radar echo images and statistics. However, nowcasting accuracy decreases as the extrapolation time increases.

Abstract: The main objective of this paper is to establish a class of new nonlinear Volterra-Fredholm type sum-difference inequality with two variables. By technique of change of variable, amplification method, difference and summation and inverse function, upper bound estimations of unknown functions are given. The derived results can be applied in the study of solutions of Volterra-Fredholm type difference equations.

Abstract: Based on integrated control strategy with spraying pesticides and releasing natural enemies at different fixed moments, we establish a pest management model with impulsive control. Using Floquet theorem of impulsive differential equations and comparison theorem, we obtain the sufficient conditions of globally asymptotical stability of the pest-eradication periodic solution and permanence of the model.

Abstract: For building high precision yarn tension control model, grey prediction method was first employed in this paper. The commonly used GM(1,1) model was modified by means of changing the coefficient a and b. Then the next tension value was forecasted from the previous test values by the modified GM(1,1) model. Then the forecasted values and the referred value were import into the self-adaption PID model. And the PID model output the control sign to magnetic particle clutch. The simulation of the control algorithm was completed in MATLAB 7.0. The simulation result showed that the proposed control algorithm had better precision than general PID and general grey prediction control algorithm.

Abstract: This paper analyzes the object-oriented modeling technology of IEC 61850 standard and the modeling steps of condition monitoring intelligent electronic devices (IED). Aiming at the problem of the existing configuration tools poor scalability for the IEC 61850 standard, a new design method of the IED configuration tool is brought up. Information model of transformer condition monitoring IED is established including logical device (LD), logical node (LN), data object (DO), data attribute (DA), dataset and report control block with the method mentioned above, and described with substation configuration description language.

Abstract: The air trajectory planned studied of the high-altitude long-range gliding unmanned underwater vehicle (HALRG-UUV) based on segmented control strategy is proposed. The aim of this research is twofold. On the one hand, specifying an altitude penetration strategy at the end of the gliding stage was presented with the aim of improving the vehicle glide ratio and achieving penetration. On the other hand, a rocket deceleration strategy was applied to adjust the speed and attitude of the vehicle in order to meet the water entry requirement. Besides, six-degrees-of-freedom mathematical model of the HALRG-UUV was developed based on the Newton’s law. Dynamic simulations of the vehicle under various conditions were performed with the aid of the MATLAB/Simulink codes. The result shows that the vehicle has a glide ratio of 1/9 in the air trajectory and meets the water entry requirement above water. This study lays the foundation for the further research of maneuverability and water impact of the vehicle.

Abstract: This paper proposes a procedure and method for assessing the operation efficiency of electric power grid. The analysis of factors reflecting the operation situation is inosculated in the overall goals. An incentive regulation model based on the improved data envelopment analysis model is presented.

Abstract: For the lack of computing, storage, information integration and other aspects in traditional electric power computing platform, it is necessary to introduce cloud computing to it and to build a cloud computing platform based on open source Hadoop to meet the requirements of smart grid. As the single point of failure of Hadoop cannot guarantee the high availability that electric power system requires, this paper gives a solution that based on hot standby mechanism and automatically failover controlled by Zookeeper, analyses availability and disaster recovery times to ensure the electric power system provides fast and accurate service.