Advanced Materials Research Vols. 791-793

Abstract: Role-based access control policy has been widely applied to various access control system design. In order to improve the flexibility of authorization check design and convenience of management, this paper uses the principle of dynamic proxy design to optimize this process, also provide a method which is Spring AOP based of transaction management for program running. The role-create method proposed can configure the users authority flexible. The improved design concept can achieve the basic requirements if role-based access control policies, and improve the efficiency of project development and security of application system maximum.

Abstract: In order to guarantee the high rate, high throughput and low latency and reliable service provided by TD-LTE system under various mobility conditions, handover (HO) procedure and its performance are of high importance. Based on research on structure of TD-LTE system and RRC (Radio Resource Control) layer, this paper proposed intra-system handover procedure in RRC layer of UE side. Simulation of the proposed design and implementation on SDL (Specification and Description Language) /TTCN (Tree and Tabular Combined Notation) verified its conforming to 3GPP conformance protocol specification. Finally, proposed design was verified on the chip ARM1176JZF-S with the corresponding software.

Abstract: Consistency test is an important part in protocol development. This paper not only introduces standard of TTCN-3 and structure of LTE system layer 2, but also set an example of RLC layer to analyze the test model and designed a new test method through the development of TTCN-3 abstract test set. Based on the TTCN-3 test set of TTworkbench platform from Test Technology, the protocol consistency in RLC layer is verified and the effectiveness of the new method in consistency test is proved. Now the scheme has been applied in the project LTE system TTCN expanding test set instrument.

Abstract: EVT transmission in Planetary Gear Hybrid Electric Vehicles makes it available that the engine works on the optimal curves; yet because of the speed limitation of motor MG1, the maximum output power of the engine is a function of vehicle speed. The maximum traction and regenerative braking power is also a function of vehicle speed. Based on this, the vehicle drive modes consist of EV mode, economy mode and power mode, and braking modes include the regenerative braking mode and electromechanical braking mode.

Abstract: Based on the techniques of dynamic current injection, common source node resonance, second-order linearity performance and the application of CMOS technology, a 1.8V power supply voltage active folding Gilbert-type zero intermediate frequency mixer has been designed by using Candense design system. The result of circuit stimulation shows, single sideband noise figure is 6.109dB when the mixer locates at 1MHz, 6.71dB at 100KHz, 10.631dB at 10KHz. Frequency conversion gain is 11.389dB and input third-order intermodulation point is 4.639dBm.

Abstract: A new converter with spherical cap for energy harvesting is proposed. Based on the method of separated variables within the toridal coordinate system, a corresponding analytical model for spherical cap converter is further established so as to obtain the analytic expressions of the topology capacitance and the output voltage. The concept of energy increment factor is specifically defined to denote the improvement of energy storage efficiency.

Abstract: In the design of CAN network system, as CAN bus topology will affect network performance and cost, it is important to optimize the network topology. This paper analyzes the CAN busload based on CAN protocol, calculates the upper limit of transmission message frames in a single CAN bus. As the amount of information on the bus is increasing, a single CAN bus cannot meet the communication requirements, we put forward dividing the network into multiple homogeneous segments via multi-objective optimization method, developing a genetic algorithm strategy and solving the problem in a MATLAB platform. Finally utilize the method to design a pure electric vehicle network topology.

Abstract: The paper discusses the neuron chip based on MC143150 and single-chip microcomputer AT89S51 double CPU structure AI node hardware and software design process. In the hardware introduced the ADC0809 modulus conversion chip data acquisition system,AT89S51 and MC143150 interface and MC143150 and physical network interface. In the software introduces the data acquisition, parallel slave-A mode of communication and utilization of network variables to send information from three aspects of the program design.

Abstract: The electromagnetic force which influenced by rail launcher armature position have been researched in this paper. As an important indicator, Inductance Gradient (IG) denotes the performance of rail launch, which can make the railgun performance to achieve optimal results by better design. A rectangular cross-sectional rail launcher model was built based on the Biot-Savart law in this paper. Furthermore, the analytical expression of inductance gradient can be obtained by this model. Finally, the electromagnetic force can be calculated. Some numerical simulations are made to test the validity and capability of the proposed model.

Abstract: In order to analyze the operational capability of the low voltage ride through ( LVRT) of a gird-connected wind turbine with doubly fed induction generator (DFIG) effectively, it is necessary to evaluate operation characteristics of DFIG under a grid fault.By using the transient principle of the flux of stator and rotor, the expressions of transient currents of stator and rotor of DFIG are derived under the grid voltage sag. The transient process is analyzed by using the Matlab to derive the correctness of the expression. A control strategy is presented to eliminate harmonic currents by proposing the essential factors of over-current of stator and rotor. The output active power and reactive power are calculated by using the derived expression with different voltage sags. Based on the theoretical analysis, a DFIG is established to analysis the model of LVRT. Simulation results show that the control strategy is able to eliminate the harmonic currents and achieve the requirements of LVRT.