Applied Mechanics and Materials Vols. 48-49

Abstract: According to zero-copy idea and the application of multi-core binding to realize a high-performance packet capture platform based on multi-core binding(MCPCP).By modifying the memory management mode about sk_buff in kernel,realize the user space program to directly access the data packet, which is a kind of universal significance of the zero-copy scheme. And then through the multi-core binding technique, for each CPU core scheduling and control, with multi-threaded user programs can minimize the cache jitter to improve the efficiency of packet capture. Experiments show that in the case of low-end configuration, the throughputs of MCPCP for 64Byte and 1500Byte messages are 620 ,000pps (about 320Mbps) and 78,000pps (about 941Mbps) respectively. In the high-end configuration, can reach 1.46 million pps (748Mbps) and 81,000 pps (979Mbps).MCPCP surpasses the traditional ones' in performance.

Abstract: To get more appropriate louvered fin structure of a series of subcompact radiators, Fluent was used to analyze the subcompact radiator louvered fins numerically. The fin model was verified availably by testing the error between the simulation results and experimental ones. Through modifying the critical dimension of louvered fin models, the friction factor f and the heat factor j of subcompact radiator louvered fins under different fin height were obtained. The regression analysis indicated that the friction factor was linear with fin height, and the heat factor was the power function of fin height. The dimensionless parameter j/f1/3was introduced to evaluate the comprehensive performance of fins, and the research indicated that the performance would be best when the fin height was 8.94mm. The result has a certain practical value for improving the performance of subcompact radiators.

Abstract: Aiming at the turning issue of PID control in industrial processes, a strategy of applying variable PID parameters was presented. This paper utilized the characteristic that genetic algorithm can rapidly optimize globally, performance indexes can form corresponding fitness functions through real number encoding of parameters of the controller, and best parameters of the controller can be obtained through adopting self-adaptive mutation rate for repeated genetic manipulation. Simulation results show that the method improves the optimal performance of parameters, and can achieve better dynamics performance and control effect.

Abstract: This paper proposes a distributed intelligent system for forest fire detection based on integration of information from several distributed sensors. An automatic fire detection system with ultraviolet fire detector and CCD camera is developed. The system is based on a set of image processing functions, and it also involves data fusion algorithms for cooperative perception. The experimental results verify that the method can improve the whole detection system in accuracy, and it can detect and alarm the fire of 1 over 1500m distance precisely.

Abstract: This paper discusses training structure and procedure about inversible system of neural network. Subsequently, selection of input signals is focused on. Finally, the paper proposes some principles and ways to obtain training sample of inversible system.

Abstract: A new type of steel wire rope non destructive evaluation (NDE) apparatus is presented. It is composed of Hall sensor and signal processing system based on embedded micro processor. The apparatus detects flaws of steel wire rope real-time and on-line. The detection principle, hardware structure and software design of the apparatus are introduced. Examples of the application are given. The experiment results show that quantitatively defect detection of steel wire rope is attained. The apparatus can also be used for the test of the ferromagnetic bars.

Abstract: In this paper, a new gait research for humanoid robot is presented. By computing the trajectory of center of mass (CoM) for humanoid robot, trajectory of hip joint and ankle joint are developed based on 3D inverted pendulum model. The actual location of the waist position obtained by multi-link model through the center of mass for humanoid robot is in coordinate of the waist of humanoid robot. Trajectory of hip joint and ankle joint are calculated. This paper presents a gait generation method with curve fitting. Using genetic algorithm, humanoid robot can autonomously search for a good gait trajectory. The experimental results show that gait trajectory for humanoid robot can be generated by applying to genetic algorithm. Our proposed method is verified satisfactorily.

Abstract: During the space electronic system in carries out the exploratory mission in the deep space, it maybe faced with kinds of violent natural environment, to electric circuit's performance, the volume, the weight and the stability proposed a higher request, the traditional circuit design method already more and more with difficulty satisfied this kind of request. The traditional circuit design method already more and more with difficulty satisfied this kind of request. But unifies the programmable component and the evolutionary algorithms hardware may the dynamic change hardware's structure adapt the adverse circumstance, resume the damage of the function, the adaptation for the duty change. In view of the Xilinx Company's FPGA unique feature, proposed one kind of evolutionary algorithms which uses in the space electronic system circuit optimization design and through the experiment proved, the algorithm obtains the circuit structure to surpass the tradition circuit design method.

Abstract: A set of TWACS system is designed and implemented in this paper by analyzing the transmission characteristics of the TWACS signals in the industrial power. And its synchronization information is modulated by pseudo-noise code, and the synchronous detection is conducted by using signal synthesis and time-frequency analysis to determined the demodulation domain, then data demodulation is realized by using cross-correlation technique. This method is able to adapt to the bad channel environment in the industrial power.

Abstract: The characteristics of the continuous wavelet transform scalogram of the aeroengine vibration signal could show the fault symptomatic in the 2-dimensional space and identify the rub-impact fault of the aeroengine. In order to get the precise feature for fault analysis, the statistical features of the scalogram which incorporated the Tamura vision features were proposed to diagnose the aeroengine rub-impact faults quantitatively. The experiments on the aeroengine test data demonstrate these statistic characteristics of the scalogram effectively diagnose the rub-impact faults.