Applied Mechanics and Materials Vols. 511-512

Abstract: In order to overcome the low speed serial links of the bandwidth low, easy to produce decline, low rate of transmission characteristics, This paper design a transmission optimization system, In the system, this paper proposes a forward error correction and data compression transmission optimization combined method, Transmission optimization technology in recent years has been widely used in the field of network communication. Transmission optimization technology has been shown to improve the utilization rate of bandwidth, improve transmission efficiency. In this paper, the transmission optimization of the forward error correction technology has carried on the simulation test, And the analysis of experimental data were compared before and after the optimization, The experimental results show that the proposed transmission optimization method for low speed serial links the data transmission efficiency has been obviously increased . Transmission Optimization Technology Transmission optimization techniques include forward error correction, data compression, and adaptive protocol of three parts, combined guarantee bad message transmission efficiency in transmission environment. This paper mainly studies the transmission on the wireless communication channel environment serial links optimization techniques. Bandwidth Compression Technology. Bandwidth compression is transmitted through compression technology after traditional smaller packets, such as real time transmission of packets is more than the number of packets before compression, so as to realize the goal of improving transmission speed. Bandwidth compression technology is not really to data compression, because the network of packet size and length size has strict rules, if the size of the data has changed, and is also change his nature. So the true meaning of bandwidth compression is part of the data in other ways to replace, including cache corresponding not change information data or with short data instead of long, Then after receiving inverse substitution process, complete the purpose of saving bandwidth. The most commonly used three kinds of compression algorithm: Huffinan coding, dictionary coding and arithmetic coding [.

Abstract: An improved pure pursuit path tracking algorithm is presented for a four-wheel steering (4WS) carrier vehicle to follow a desired path automatically. A bicycle vehicle model considering the 4WS carrier vehicles structural and steering features is applied in the method. Real vehicle tests in an open large outdoor warehouse showed that the lateral tracking error was less than 0.56m at 20km/h. And we can conclude that the enhanced method for 4WS vehicle has good tracking ability on flat road.

Abstract: In this paper we consider a procedure for the estimation of origin-destination (O-D) matrices for a multimodal transit network. The structure of urban multimodal transport system is fully analyzed and then a bi-level programming model is established for O-D demand matrices estimation, where the upper-level problem seeks to minimize the sum of error measurements in traffic counts and O-D matrices, while the lower-level problem is to assign a target O-D matrix onto the network according to the user equilibrium principle. And a heuristic algorithm is proposed, finally a numeral example is given which indicates that the solution approach can be applied in practice.

Abstract: In this paper, a new interpolation operator is designed basin onred-black coarsening. Combining the interpolation operator, acascadic algebraic two-grid (CATG) method and a cascadic algebraictwo-level (CATL) method for the elliptic problems of second orderare presented. Numerical experiments show that the betterapproximate value is obtained without smoothing on finer level, andthe new methods reduce computational cost.

Abstract: Reasonable Optimization of maintenance schedules for railway signal equipment can avoid or reduce the excess or lack of maintenance in the maintenance process to achieve high efficiency and economy. This paper establishes the constrained minimum cost model to optimize the interval timing replacement for equipment. The model takes the minimum cost as the objective function with availability and fault risk as the constraint condition and takes the actual survey data of someone station as a basis for case study.The optimization program of maintenance plan that is acquired by the established model and its solving method as well as the Monte Carlo simulation verify the validity and practicality of the optimization model.

Abstract: The sense of behaving reality in the container crane simulator depends on the dynamic model of the crane spreader in three-dimensional space. The movement of simulating objects in the crane container simulator is discussed. Simulating objects include gantry, trolley and spreader. The paper adopts the second Lagrange equation. Through reasonable hypothesis, 4-DOF dynamic model of the spreader is derived in the generalized coordinates system. With the different length of sling and acceleration of the trolley, 4-DOF model is analyzed by dynamic simulation. Matters needing attention are summarized for the process of container handling. At last the paper gives a simulation example.

Abstract: Based on adaptive nonlinear feedback technique, two appropriate controllers are designed to suppress the chaotic behavior of the whole family of the generalized Lorenz system. The derived controllers have nonlinear compensator mechanisms to compensate the system nonlinearities and external disturbances. As a result the output trajectory control is accomplished. According to Lyapunov stability theory the stability analysis of the closed-loop control system is deduced. By numeric simulation, it has been shown that the designed controllers can successfully regulate the chaotic motion of the whole family of the system to a given point or make the output state to track a given bounded signal with great robustness. At the same time the required closed loop behavior is obtained. The most important effect of this letter is that under the actions of the universal controllers deduced from the adaptive technique the problem of chaos suppression of all the Lorenz-type systems can be solved successfully. Moreover the controllers have the ability of attenuating disturbances and the controller parameters are easy to tune according to rigorous analysis of stability. Based on theoretic analysis the designed controllers also provide a heuristic approach for other chaos suppression problems.

Abstract: In view of the traditional double motor constant pressure water supply system without tower in the operation process of the problem of short service life, the design of a new type of dual voltage no tower water supply control system. The control system uses PLC, soft starter and frequency converter technology, the soft starter can make the motor to realize soft start and soft stop, no impact on the motor, can extend the service life of the motor, avoid pumping station "door" damage, reduce repair costs and repair work. The running results show that, after the reformation of water supply system can save more than 21% energy, but also improve the quality and reliability of the water supply.

Abstract: In this paper, the problem of function projective synchronization is investigated for complex networks with stochastic effects. A hybrid feedback control method is designed to achieve function projective synchronization for the complex networks. Using Gronwally' inequality, we obtain some conditions to guarantee that the complex networks can realize mean square synchronization and mean square exponential synchronization, respectively.

Abstract: For the failure of current sensor on maglev train, an active fault tolerance control strategy based on feedback gain reconfiguration is proposed. Fault diagnosis unit based on state observer is designed to detect the output of current sensor, the diagnosis result is used to switch the control strategy. Simulation result indicates that the fault tolerance strategy meets the demands of the system.