Applied Mechanics and Materials Vols. 427-429

Abstract: The voltage-controlled beam scanning antenna array based on the CRLH transmission line is designed with series power divider and three small antenna. The resonant frequency of the open-termination power divider is 2.5GHz, and the varactor bias voltage of the small antenna is from 8V to 2V. At the operating frequency of 2.5GHz, the horizontally polarized pattern of the antenna array is measured. When the bias voltage of the varactor is changed, the antenna array radiation beam scanning range is up to 96 degrees, and its radiation from backward to forward can be achieved by controlling the varactor bias voltage.

Abstract: In view of the problem of robust tracking of maneuvering target under LOS/NLOS condition, an IMM algorithm based on AR prediction model is proposed (ARIMM). First of all AR prediction model is adopted to model the motion state, and secondly UKF and RUKF are utilized separately for the reason that the state LOS and NLOS have different distribution of observation noise, and the IMM filter is used to estimate the position of BS, and finally the position is used to update the current parameters in AR prediction model and make the AR model more matched with the true motion state. Simulation result demonstrates that the proposed algorithm performs better robustness under LOS/NLOS condition compared with the traditional UKF and RUKF.

Abstract: Nowadays with the increases of the density of large scale integrated circuits, researches of Design for Test (DFT) become more and more important, JTAG (JTAG: Joint Test Action Group, also called Boundary Scan ) has been widely used in test area , which improves the testability and reliability of mixed-signal circuits. This paper puts forward a scheme to design a Built-in Test System (BITS) based on boundary scan technology. The BITS is realized in a weapon electronic control system, which is composed of mixed-signal circuits including ARM, AD/DA, FPGA, etc. With this method, several test experiments are carried out in the BITS, which include infrastructure integrity test, interconnect test, cluster test, AD/DA test and so on. The results of experiments show that the Built-in Test System based on JTAG can work normally, which is able to reduce effectively the complexity and the time of test. In a word, the capability of BITS is viable and the system is a virtual tool in the process of DFT design and application.

Abstract: Based on platinum resistance as temperature medium, according to the measurement precision requirements during geothermal testing process, optimize the circuit design and segmented curve fitting were used, discussed the feasibility of realize high precision temperature detection. Combined with high precision temperature measurement circuit, through the single chip microcomputer control, segmented curve fitting the temperature sampling value, get the corresponding D-t curve, and compensate the nonlinear relationship of platinum resistance in the practical work, to achieve the purpose of accurate measurement of the temperature.

Abstract: The system equivalent rotary inertia and frequency control capability are decreased with growing continuously of wind power penetration, because the doubly fed induction generator (DFIG) is decoupled from system frequency, which will bring a new challenge to the large wind power integration. On the basic of analyzing power-speed characteristic of DFIG which operates at different wind speeds, the de-load operating strategy of DFIG based on coordinated controlling of over-speed and changing pitch was proposed, at the same time the de-load operating curve of DFIG was given through calculating, and the enhancing of kinetic energy was proved by theoretical analysis. And the power reserve capacity of system is enhanced.

Abstract: A novel broad band and wide beam microstrip helical antenna is proposed based on the modification of traditional helical antennas. Through selecting the appropriate operating mode between the axial mode and the normal mode, this new antenna can broad both the beamwidth and the bandwidth. To improve the gain of the antenna, An antenna array with 1*16 elements is designed and fabricated. Meanwhile, cavity-loaded feeding network is utilized for probe station measurement. The simulated impedance and radiation pattern are studied. The proposed antenna shows a wide impedance bandwidth from 7.6GHz to 9.6GHz for |S11|<-10dB, with wide 3dB beamwidth of E-plane about 120⁰, respectively.

Abstract: In order to improve software reusability of automated test scripts, presents a keyword-driven test automation framework (KDTFA). First, the current existing automated testing framework for inductive analysis; then raised KDTFA system architecture; finally, an example of the android interface application framework and the existing framework for KDTFA actual contrast verification results show that the framework has a reduced scale of test scripts to improve the overall test efficiency and other advantages.

Abstract: In this paper, the methods of gas producing automation control transformation and related experiences of a gas plant were investigated. During the project, the equipments for instrument testing were transformed, the valve control system was improved, a blower converter was set up, and the DCS System was applied to test and control the flow of gas production. In addition, the plant developed the automatic coal-refilling system, the blower frequency conversion control system and the gas load balance adjustment control system according to the characteristics of productive technology and equipments. After the project, the automatic control capability of gas production of the full material bed was improved. The gas production was stabilized and the operators' labor intensity was reduced to a new low. Various technical and economic indicators were greatly improved.

Abstract: In order to meet the testing requirement of positive and reverse operation large torque load for new rudder, an electrical load simulator is designed. The system mathematical model is established and the feedforward compensation control of torque and rudder angle is adopted to restrain the surplus torque according to the principle of invariance. The high precision large torque load under positive and reverse operation for rudder is realized by torque and position hybrid control. The practical application shows that the proposed method can effectively restrain surplus torque and the system meets the high precision torque load under positive and reverse operation for rudder very well.

Abstract: This paper mainly Study the satellite emergency communication characteristics of reliable data transfer protocol, combined with the UDP protocol and the TCP protocol of the advantages and disadvantages. The article puts forward an improved expanded with reissue of double reliable D-RCUDP protocol. This paper introduces the application background, the hierarchical structure, the core mechanism, application platform and experimental results.