Applied Mechanics and Materials Vols. 511-512

Abstract: Dispersion and nonlinear effect of fiber is the main factor limiting the performance of the long-haul and high speed optical transmission system. This paper focuses on the analysis and modeling of nonlinear phase noise in quasi-linear optical transmission system. The analytical expression for the nonlinear phase noise is obtained basing on the first order perturbation theory. And the numerical calculation of the nonlinear phase noise is deduced. The calculation results show that when the noise source and the end point of the system is equidistant from the optical phase conjugation (OPC), the nonlinear phase noise added by the optical amplifiers can be compensated by the OPC located after the optical amplifiers.

Abstract: This paper presents a novel improvement to the LMS method which seeks to set different step sizes to different weights depending on their relative sizes. Sample numerical simulations carried out to identify different plant configurations shows that the proposed method provides an early convergence and thus identifies the plant earlier.

Abstract: This paper proposed a fuzzy curve detection method based on lateral acceleration.First, the dynamics model under the curve driving condition was created.Then, the relationship between the lateral acceleration and curve was analysed. The fuzzy curve detection algorithm based on lateral acceleration and its rate of change was realised. The test results showed that this method is feasible and the detection result can be used in automobile electric control system, for example automatic transmissions control system, etc. The security under the curve driving condition was also improved.

Abstract: Pedestrian detection based on images is one key technology of intelligent vehicles, and it is also widely applied in intelligent robots, intelligent surveillance. This paper mainly focuses on implementing a pedestrian detection system, which is classified by linear SVM with optimized Hog (Histograms of Oriented Gradients) as the extracted features. Then some experiments were done to find out that how the changing resolution of training set, times of bootstrapping iterations and different size and steps of the sliding windows affect the overall performance of detecting systems.

Abstract: In this paper, two digital elevation models of debris flow in Yingxiu mountain area are generated; one is from contour lines with manual interpretation before earthquake and the other is from high resolution aerial photos using MapMatrix software. By analyzing three random points which are not in the same edge, a new formula for calculating the volume from these three points to their projection on the datum plane is derived. Then, the volumes of the two DEMs before and after earthquake can be calculated, and the volume of the total debris flow is the difference of those two.

Abstract: Using YanHua USB-4718 eight-channel thermocouple input module, PC machines as the main hardware,the Labview of National Instruments (NI) company as the software development platform, building thermocouple test data recording sheet, automatic collection standards and the tested thermocouple mill volt values and the related standards. According to thermocouple calibration data processing formulas, will calculate the error of the thermocouple each test point automatically. It will achieve visual user interface, save test data, test certificates and achieve other functions.

Abstract: This study focuses on the development of transducers for Osstell^® Mentor in measuring stability of various implant systems. Experiments are performed to verify the compatibility of a self-made transducer. An acoustic signal analysis system is introduced to analyze the acoustic signal emitted from the Osstell^® Mentor probe, and the frequency with peak amplitude in the amplitude-frequency plot is identified. The resonance frequency obtained is found to be linearly dependent upon the ISQ value by Osstell^® Mentor. This finding is helpful for developing compatible transducers for various implant systems.

Abstract: Key structure of multi-planetary gear transmission such as gear box body, planetary carrier should be monitored by non-destructive testing technology under work to ensure reliable operation. However, temperature of such components under operation is not normal, which will affect the detection result. Temperature influence upon ultrasonic on-line detection was researched. Such factors as ultrasonic propagation velocity, ultrasonic attenuation, ultrasonic probe emissive power and refraction angle of angle probe were analyzed. Multi-planetary gear transmission ultrasonic monitoring case has been completed.

Abstract: The speed is the most common frequency signal among a lot of the automotive signal which may be collected, Acquisition for frequency signal generally use the counter input capture. The number of sampling rate not only depends on clock frequency counter, but mainly the number of the frequency of the signal itself, it is bound to take a very long time to collect speed signal when the speed is very low. For most of the data acquisition card, which usually adopt asynchronous acquisition between various channels, that is, only one channel can collect data at any time, so for the multi-signal acquisition system which has a high requirement for real-time, it is undue to collect directly low frequency signal. This paper adopt method of frequency-voltage converter to change the frequency signal to analog signal and collect data, thus, which can greatly improve the system's sampling rate.

Abstract: Project Moiré Interferometry system includes fringes projection system,image acquiring system and image processing system. Laser beam is changed to planar optical wave by expanded beam collimation system.The ideal grating is produced when planar optical wave passes through spatial light modulator. The emergence of light waves which include the information of grating are projected on the model surface.The fringes image modulated by the height of model surface is formed. The image is captured by image acquiring system to be processed.After the distortion brought by camera perspective transform is eliminated,the image is added with reference stripes.The Moiré fringes containing information of model surface can be obtained.Quantitative continuous data of model surface shape can be gained after fartherly image processing.