Applied Mechanics and Materials Vols. 457-458

Abstract: This paper designed a kind of DES algorithm implementation based on DSP technology, application of TI company C54x series general DSP implementation mechanisms, with the introduction of DSP, this paper proposes a new DES algorithm implementation approaches, and the implementation scheme is presented. The method is simple and practical, the hardware resources is relatively less, high transmission efficiency , suitable for low data rate data encryption of small wireless data transmission system, can be widely used in various kinds of terminal positioning and small digital wireless receiving system.

Abstract: Weak security of RFID system is concerned by more and more people because of the fast development of internet of things. Some existing RFID authentications protocols begin to be analyzed, such as Mutual three-pass authentication, randomized Hash-Lock, which has some problem of being difficult to resist a variety of network attacks such as forgery tag attacks and a new bidirectional security authentication protocol,A multiple security authentication protocol is proposed to overcome the disadvantage of being vulnerable to cyber attacks. Analysis shows that this approach is of good security and privacy, low cost, and high efficiency.

Abstract: The paper is based on the one-quarter vehicle vibration model of air suspension system with auxiliary chamber and stiffness adjustment theory and control characteristic of air suspension are discussed. On the basis, fuzzy control theory without mathematical precise model was applied to design the air suspension controller, and then an electronic control unit for air suspension is developed.

Abstract: The safe obstacle avoidance is a basic problem on mobile robotics research. The premise of realizing safe obstacle avoidance is achieving the accurate information for obstacle avoidance which provides reliable indication on the surrounding environment for mobile robot obstacle avoidance processing. The sensors are used to measure and obtain the obstacle avoidance information for obstacle detection and ranging. Based on "Future Star" platform, a remote control application of ultrasound obstacle avoidance has been developed to implement obstacle avoidance capabilities on the study of ultrasound obstacle avoidance strategy and path planning.

Abstract: The theory of modern immunology provides a novel idea to study network intrusion detection and defense system. With the concepts of self, nonself, close degree and membership in an intrusion detection and prevention system presented in this paper, a model of detector generation based on immune recognition and redundancy optimization is proposed, in which detectors are generated by clone selection, genetic variation and evolutionary algorithm, as well as the improved redundancy optimization algorithm. The simulation experiments show that the model has higher detection rate and lower false detection rate.

Abstract: Automatic grouting is a very important part in the well drilling process. The stability of grouting system is one of the factors affecting the drilling accident. This paper presents a automatic grouting method based on network control system. In order to find out the influence on the control performance after using network in the system, paper sets up the system model with the simulation toolbox TrueTime-2.0 of MATLAB and separately studies the influence on the control effect by network delay and data packet loss according to the simulation result. The results prove that both the network delay and data packet loss all make great differences on the control performance of system, so we need to take appropriate strategies to reduce the influence in the actual designs.

Abstract: This paper describes the new method that improves the processing and storing of data, which was used during the development of distance teaching system. Usage of a modern methodologies and good practice has reduced the time cost for working with information, helps to identify the out of day information, operate potential risks and shows how to receive competitive advantages.

Abstract: According to characteristics of the thick overburden dam and the current and main problems on seepage of the thick overburden concrete face rock-fill dam, this paper takes finite element method to analyze the three-dimensional seepage field of thick overburden CFRD after the joint sealing failure, and studies the seepage field distribution of the CFRD after sealing failure, and analyzes the sealing failure position and influences of seam length on each seepage elements variation. In this paper, taking the thick overburden CFRD in xinjiang as an example, effects of the joint sealing failure on seepage related factors are discussed , the change rules of saturated faceseepage discharge and seepage gradient of the thick overburden CFRD are obtained by studying,. The research results can provide a reference for a parallel engineering design and construction.

Abstract: The synthetic efficiency of hydroturbine is the foundation and important basis of economic operation of hydropower plants. However, the traditional calculation methods have large amount of calculation, large errors and other problems. To solve the problems better, this paper introduces the Elman neural network and BP neural network to calculate the synthetic efficiency of hydroturbine. Comparing the results of the Elman neural network and the traditional BP neural network, the result shows that, Elman neural network is an effective way to improve the learning speed, effectively suppress the minimum defects that the traditional neural network is easily trapped in, and reduce the error. The result suggests that the Elman neural network has better nonlinear mapping capability than the BP neural network.

Abstract: The bidirectional DC/DC converter is an important part for the power energy storage system,this paper adopts a triple bidirectional DC/DC converter in view of the features on super capacitor energy storage wide output voltage range. Establish the switch average model of bidirectional DC/DC equivalent model, put forward a double close-loop control strategy in view of charge and discharge conditions of the super capacitor, the triple bidirectional DC/DC simulation model based on super capacitor is built. The simulation results show that, the triple bidirectional DC/DC converter can effectively reduce the inductive current and current stress demand of the switch devices, improve the converter power grade. The control strategy can effectively control the super capacitor charge and discharge and it is suitable for application in the power energy storage system.