Applied Mechanics and Materials Vols. 427-429

Abstract: In this paper, a novel extended interaction klystron output cavity is presented. With the help of a three-dimensional (3D) particle-in-cell (PIC) simulation, design and optimization geometry of the cavity is performed, which is composed of ladder loaded rectangular waveguide. In present work, the output continue wave (CW) power 724W is achieved, the efficiency and bandwidth reaches 7.5% and 1300MHz, which is operating at beam voltage and beam current is 16 kV and 0.6A , respectively.

Abstract: In large and high power laser facility, Vacuum system is an important subsystem of laser facility. It provides reliable, stable and clean vacuum environment for physical experiments. Because of its huge scale, vacuum system stands on a spread and broad district. The vacuum system is composed of some independent subsystems, and every subsystem is composed of PLC control system. So, distribution network control mode is just adopted for the vacuum control system. Each sub PLC system and main PLC system compose large laser facility vacuum control system. Main control system uses monitor computer to control each subsystem and communicates with upper control system through Ethernet. Field equipments drive the vacuum preparation equipments by switch or data format. Through main PLC, field control PLC and equipments obtain, it can gather accurate vacuum gauge pressure data and control all vacuum pumps and valves no mistake.

Abstract: Wireless communication technology has become another research focus in the field of industrial control. It, which is a revolutionary technology that can increase the scope of application of industrial measurement and control system, can be used not only as a supplement to the wired network, but also as a independent network. This article focuses on the wireless network communication protocol commonly used in modern industrial control, and highlights the wireless communication protocol ZigBee based on IEEE 802.15.4 and its characteristics. From the low-power, low-cost point of view the overall design of embedded wireless communication system which is based on ZigBee technology in industrial control are proposed, meanwhile it put forward the basic framework of wireless network nodes ZigBee, and the options of industrial site networking mode.

Abstract: In past few years, with the rapid expansion of computer networks, security has become an important issue for modern computer systems. Intrusion detection technology is an effective way to detect illegitimate use to ensure network security. In this paper, we proposes an intrusion detection system based on a feedforward neural network-aided grey model (FNNAGPM), by integrating a first-order single variable grey model (GM(1,1)) and a feedforward neural network. There are three phases in the system process, including initialization phase, GM(1,1) prediction phase and FNNAGPM prediction phase.

Abstract: This paper introduces a design of liquid crystal GPS positioning terminal based on microcontroller, the system consists of a GPS module, 12864 liquid crystal display module, MCU minimum system module, power module. The paper mainly puts forward the scheme and software design idea, hardware design and debug, the extraction system can realize the positioning and navigation information parameters of GPS global positioning system and the information parameters is analyzed.

Abstract: RMB contains a large number of coins in circulation in the financial and other fields, this coin inventory and classification, is through manual means, this mode of operation and low work efficiency and give the operator a great trouble, the labor intensity greatly, and not accurate. In the paper, an automatic sorting and measuring machine has been designed and mainly used for sorting, counting, packaging to a variety of coin. The main function of automatic sorting and measuring machine are automatic sorting, counting and packaging. The machine mainly consists of mechanical systems and control systems. It is applied to the modern innovative design and it is the device meeting the need in places for many small denominations of currency. The machine has achieved automation, improved labor productivity, and also brought many conveniences to life. The machine is the inevitable trend of future development.

Abstract: Intelligent Mouse is a micro-robot with special wisdom and it is a typical electro-mechanical integration system. This document has detailedly described the facture of mechanical structure, circuit design, software algorithm and other hardware system configurations. For the hardware, the control center of this mouse has used LM3S615 microcontroller which is based on the ARM® CortexTM-M3 v7M architecture developed by Luminary. This document also introduced that, the left/right-hand searching of the mouse, mapping, and calculation of the shortest path.

Abstract: This paper studies the realization method of QPSK modulation and demodulation circuit based on FPGA.And the simulation results are given under the environment of MAX+PLUSII .In this paper, the scheme uses phase selection method, compared with the modulation and demodulation method commonly used, design more simple, more suitable for FPGA implementation, the reliability of the system is higher.Through the analysis of the simulation waveform shows, the very good realization of the QPSK modulation and demodulation function.

Abstract: Quadrature Phase Shift Keying as a efficient modulation mode to be used in wireless communication. it is significant to study its implement. This paper presents a method to design QPSK modulator and demodulator, which use field programmable gate array. We will analysis the principle of QPSK modem and will give the design method, display the block diagram of the system in this paper and discuss its feasibility. The whole system is divided into several small models. Because space is limited, we can only introduce some key modules. Such as carrier recover and bit synchronization

Abstract: An evaluation scheme of skywave radar coverage of ship target is researched. On the basis of fifteen kinds of indexes of the skywave radar coverage, a sort of model of coverage quantitative evaluation with three levels of hiberarchy is established by means of the modified analytical hierarchy process (AHP) based on grey relational grade (GRG), the quantitative calculation method of all level indexes is discussed, and the effectiveness ofthe model is verified. This method solve the problem in AHP effectively. The result shows that the evaluation scheme of skywave radar coverage is feasibility.