Advanced Materials Research Vols. 756-759

Abstract: In order to extract characteristic values of graphene, a method based on a series of digital image processing algorithms was proposed in this paper. Using the method, we can automatically analyze topology structure and calculate amount of carbon atoms, and even calculate chiral vector indices (n, m) during in-situ TEM scanning of graphene. At last, we also write the correlative software with c++, which applying the digital image processing algorithms, and give out the processing result of several classic TEM image of graphene.

Abstract: In this paper, we describe an real-time algorithm to detect 3D hand gestures from depth images. Firstly, we detect moving regions by frame difference; then, regions are refined by removing small regions and boundary regions; finally, foremost region is selected and its trajectories are classified using an automatic state machine. Experiments on Microsoft Kinect for Xbox captured sequences show the effectiveness and efficiency of our system.

Abstract: The Passive Location of Emitter based on Fuzzy Method.[Purpos The use of passive observation station to achieve the precise location has been an important topic of monitoring the electromagnetic spectrum resources and the environment. In order to locate the emitter accurately, a new method called fuzzy method is presented in this papers. [MethoBased on the distribution of points of intersections that are figured out by the LOB(Lines of Bearing), the paper put forward a fuzzy method for the passive location of emitter based on membership function to achieve the location of emitter. We compared this method with Pages method using 100 sets experimental data through the Monte Carlo simulated experiment. [Result The results showed that this method can effectively achieve the location of emitter, and improve the location accuracy. [Conclusion The positioning precision of this algorithm is obviously superior to Pages algorithm.

Abstract: Based on the analysis of the characteristics of sine-wave pulse-width modulation (SPWM) and space vector pulse width modulation (SVPWM) [, the key points are the algorithm of various sampling methods of PWM signals and the analysis of those signals spectrum with MATLAB[4]. The foundational features of the harmonic distributions and advantages and disadvantages of various sampling methods are obtained. According to the analysis, some suggest can be given for the evaluation of pulse width modulation scheme. In the same time, some methods of optimization of pulse wave are advised to provide theoretical guidance for the system design.

Abstract: Pulse wave signal is analyzed in this paper especially the type I smooth pulse is selected to be further discussed. CPU is designed by using FPGA chips. This CPU contains various IP cores components, and can carry out multiple calculations and driving peripheral function. This paper implements the extractions the feature points of the specific pulse waves by using the CPU. The result of the design is basically ideal and achieves the expected target.

Abstract: This paper studied GPS location information of the collection, processing, GPRS data transmission network, intelligent building security system features. Based on this techniques, we designed an embedded GPS/GPRS intelligent building security system, which is composed of ARM9 microprocessor S3C2410, GPS/GPRS module and some peripheral devices. The system is running under Linux OS. The characteristics of the system are flexible, powerful, and high practicality.

Abstract: Based on working Principle of the direct-drive wind power systems grid-connected inverter was research, the mathematical model for inverter in Three-phase rotating coordinate was established and analyzed. A double-loop control strategy that based on feed forward decoupling were introduced, Meanwhile, combining the implementation effective control of the AC-side output current by the Space Vector Pulse Width Modulation method (SVPWM), it could generate sine wave current that had the same frequency and the same phase with network voltage. To a great degree, reduced harmonic pollution in power system, moreover, improved the Grid-connected wind power systems efficiency and reliability.

Abstract: With the Asynchronous wind generators as research object, this paper analyzes the problems of the voltage stability and the generation mechanism of the reactive power compensation during the wind farms connected operation. For paralleling capacitor bank has shown obvious defects, therefore this paper employs dynamic reactive power compensation to improve reactive characteristics of grid-connected wind farms. With the influences of different wind disturbances and grid faults on wind farms, wind farm model is set up and dynamic reactive power compensation system and wind speeds are built in the Matlab/Simulink software, The simulation result shows that they can provide reactive power compensation to ensure the voltage stability of the wind farms. But STATCOM needs less reactive compensation capacity to make sure the voltage and active power approaching steady state before the faults more quickly, Therefore STATCOM is more suitable for wind farms connected dynamic reactive power compensation.

Abstract: The paper introduces an electrical design to dilute heavy crude oil. The design is based on the feedback principle and includes detection part, control part and actuator part. The practice proves the design is reliable and accurate to realize the proportion between the crude oil flow and dilution liquid flow.

Abstract: This paper proposes an adaptive power allocation in multiple-input multiple-output (MIMO) spatial multiplexing slow fading channels, which improves spectral efficiency and reduces the complexity of systems at the same time. Under the constraint of the same signal-to-interference and noise ratio (SINR) at each receive antenna, an iteration formula of power allocation algorithm for transmit antennas is derived. Besides, for a certain channel gain matrix, the same SINR value at each receive antenna is proved to have the limit value. The simulations of the proposed adaptive power allocation show that the algorithm is effective and can reach the convergence fast.