Advanced Materials Research Vol. 650

Abstract: The capacity of electrical cables buried in the same cross section depends on the capacity to dispose of heat into the ground around him. This depends on many factors: soil characteristics, moisture, installation mode etc. The CEI 20-21 regarding the uses expressions that sometimes are not very cautious and dimensioning of insufficient capacities for cables. This work has been done a study of the behavior of underground cable based on using a forecasting model that uses the techniques of cfd. This model was validated with a physical model in miniature, made from data collected in situ measurement campaigns carried out in underground conduits in the province of Foggia (Italy) that allowed the choice of the mesh to get more 'correct solution to of the problem. Thus it was possible to evaluate the differences with the CEI and attribute the correction factors that lead to more realistic values.

Abstract: This report offers the solution that allows increasing the correlation leak detectors accuracy to a certain extend. This solution is based on signals frequency spectrum data and signal analysis time-frequency correlation method development. The idea is to analyze the correlation of two signals, to determine valid signal frequency limits and to set on this basis frequency filters parameters to improve signal-to-noise ratio.

Abstract: Aiming at the limitations of the orbital dynamic equations based star sensor navigation method, a star sensor /geomagnetic information utilized aircraft autonomous navigation method is proposed. Dynamic equations applicable to general aircrafts are established. System observation equations are deduced. The angle between geomagnetic and starlight vector is used as observation in the algorithm. Extended Kalman filter is used to estimate position and velocity of aircraft in the algorithm. Singular value decomposition method is used to analyze observability of the system. Simulation results show that the algorithm has many advantages including high precision, good filtering convergence and stability, and non-accumulated error. The algorithm can be used as aided navigation of inertial navigation or in occasions, which only require a general navigation precision.

Abstract: This paper researches on Open Numerical Control System based on the PC platform, in which the motion controller works as the control core, can realize the multiaxis motion control in real time and the sequential logic control. This paper sets out from the hardware structure, use the Real-time trajectory interpolation algorithm, and choose the proper motion-control function. it can realize fast, stable and continuous movement with multistage path, and ensure that the system is open, real-time and reconfigurable.

Abstract: Traffic incident detection is critical to the core of the traffic incident management process. In order to study the highway traffic incident detection algorithm and the layout spacing of the fixed detector, under the assumptions of the linear traffic flow, to detect traffic incidents as the goal, using TransModeler traffic simulation software to simulate the highway traffic conditions from Xian to Hanzhong, getting the changes in the macroscopic traffic parameters before and after the traffic incident, and analysis of the data, finally puts forward the optimal layout of spacing of basic road traffic incident detection.

Abstract: In order to resolve the message safety problem in vehicular ad hoc networks (VANET) and improve traffic efficiency, a privacy-preserving and scalable scheme was proposed for VANET messages authentication, in which identity (ID)-based signcryption was used to help vehicles to secretly receive a secret member key from an RSU, and then the vehicles can anonymously send messages on behalf of the group. The efficiency of the proposal is at least 33% higher better than other existed scheme.

Abstract: Power unit coordinated control (PUCC) problem was being focused by many optimizers as a serious task to be tackled in several aspects. Through this paper differential evolution (DE) and particle swarm optimization (PSO) algorithms are implemented to solve the PUCC problem. With considering four objectives to be optimized: minimization of tracking error in load power demand, fuel consumption, throttling losses due to steam control valve, and feeding water. Simulation experiments are made through case-study by aid of MATLAB programs to develop the required comparison through the two algorithms.

Abstract: Composite grinding machine for non-circular shaft parts, on the workpiece servo spindle high requirements.In order to overcome the vector control coordinate calculation of complex, slow response speed and other defects, this paper adopts the direct torque control scheme of asynchronous motor spindle servo control research.Using the Matlab/Simulink module library provides the basic module, built asynchronous electric spindle direct torque control system model.Coordinate transformation process were established, flux adjust step, flux observation, link and loop PID position control module, and the use of subsystem package technology package.The current loop, speed loop, ring in position and torque simulation test, the results show that, the method of direct torque control of asynchronous motor spindle control drive control system can obtain good static and dynamic response characteristics and the closed-loop response performance.

Abstract: This paper explains the development and functioning of AC driven electrodes based sensor which is used for the study of condensation phenomena of steam. Time for the AC signals starts form 20 msecond to 1 second. Data acquisition system is employed against each time interval and the output data is fed into EIDORS (a free software algorithm). Images show the clear boundaries between pure steam, its interface and water.

Abstract: Based on the analysis and design of the entire AGV system, this paper explores the function allocation and module partition of the AGV control system. The on-board control system for AGV is divided into five functional modules such as control, communication, position, safety and driving-steering module, and the hardware choice and designing for each module is described according to the AGV’s overall performance requirements. On this basis, the software structure of AGV is designed, providing a reliable and high-performance experimental platform for AGV motion control algorithm.