Applied Mechanics and Materials Vols. 556-562

Abstract: With the gradually development of wireless sensor network technology, intelligence of hazard monitoring has been promoting. A major hazard sources monitoring system based on wireless sensor network (WSN) is proposed to solve problem of deploying the monitoring system.Compared it with the conventional supervisory control and data acquisition system,monitoring system based on WSN solves the problem of complex wiring, sophisticated maintenance, etc. The hardware platform is composed of IRIS series node and Stargate Netbridge Gateway. The application is developed by nesC based on TinyOS. EKo View that embed in Stargate display and analyze the data. Monitoring information can be explored by enterprise and department of work safety quickly and intuitively via the web.

Abstract: Leakage of the heat distribution pipeline will seriously affect the safety of residents and cause economic losses. This paper presents the transient electromagnetic method (TEM) for detecting the corrosion of buried heat distribution pipeline, which mainly introduced the principle of the TEM to detect the pipeline and the general detection method. Combining with an instance of corrosion detection of buried heat distribution pipeline in a certain street in China Hohhot, the detection results were analyzed and the feasibility of this method was proved through excavation. The results show that the TEM can detect the uniform corrosion distribution of buried metal pipeline and it’s effective and practical for detecting the buried heat distribution pipeline. The TEM could provide a new method for guaranteeing the safe operation of the heat distribution pipeline.

Abstract: The application of advanced composite materials in airplane is becoming more and more. Along with the increase of its service time, it may be abnormal. It needs to take an anomaly detection. The electrical impedance spectroscopy (EIS) is applied to the anomaly detection of composite material components in airplane. A uniplanar sensor with double-electrode and two carbon fiber composite samples are made, an experiment circuit is designed. In order to verify the effectiveness of the experimental circuit, the EIS of the Randles unit model circuit is measured, as well as the two composite material samples using the dual-electrode measurement method. The picture of EIS is drawn in Matlab and comparison and analysis are carried out. The preliminary experimental results indicate that the anomalies can be seen by measuring the EIS of the composite materials. It is feasible for the EIS to be applied in the anomaly detection of the composite materials in airplane.

Abstract: For the deficiencies of traditional PC-style vehicle fault diagnostic system, this paper proposes a kind of standardized PC-style vehicle fault diagnostic system which based on the standardized diagnostic interface device, selects MDI which conformed to SAE J2534 standard, studies the communication mechanism of MDI and SAE J2534 standard, optimizes the data read rate, develops the diagnostic system software using the design ideas of hierarchical architecture and function modularization. Through vehicle testing and analysis, this system allows the fault diagnosis, maintenance help, real-time monitoring and online refresh for vehicle electronic control system, has a good versatility and scalability, has a reference for developing standardized diagnostic device and provides the favorable tools for vehicle diagnosis and maintenance.

Abstract: The safety traffic of intellectual vehicles is mainly carried out through environmental sensory perceptual system. This thesis uses the data collected by the vehicle-mounted laser radar and puts forward to a kind of improved straight-line feature pick-up algorithm SEF-LSM-BO. It experiments on the four kinds of algorithm using the same frame of laser radar data. It turns out that compared with SEF, LSM and SEF-LSM; SEF-LSM-BO can quickly and accurately detect and merge boundaries, mark surrounding obstacles and provide traversable areas.

Abstract: In order to speed up and enhance the robustness of speech recognition system, this paper proposes a speech recognition algorithm based on segment-level features of GFCC. In training and testing stage we use segment-level features of GFCC which is more robust to noise instead of the widely used MFCC features. Experiment results show that both the training time and test time decreased, while the accuracy of system was made to improve.

Abstract: An improved background subtraction algorithm based on color separation method is improved to solve the problem of high rate of missing detection of moving targets in video surveillance. First, the algorithm implements the background subtraction of the current frame and the background frame for pixel blocks in independent RGB channels. Then the three foreground targets after denoising extracted respectively from three channels are combined by or operation to get a complete moving target. And then this algorithm removes the shadow in color model. After that the background frame from each channel is updated individually by recursive algorithm. The algorithm adopts a nonlinear way to change the learning factor for background updating. The experiments show that this improved algorithm can extract effectively foreground targets which are similar to the background’s grey level, with better accuracy and robustness.

Abstract: Melnikov function is currently the only way to theoretically resolve the chaotic threshold. Considering the calculation difficulties of Melnikov function, Gauss-Legendre numerical method is accepted in this paper to ascertain the chaotic threshold of a nonlinear system. Two forms of numerical technique, namely Lyapunov exponents and phase plan are adopted to validate the computation results. The method is applied to the ship-roll system and the chaos threshold is numerically computed in the end.

Abstract: This paper introduces a transformer automatic test system based on virtual instrument (LabVIEW) and PCI hardware platform, and being Improved separately from hardware and software section. use remote control functions to achieve relay testing automatic commutation function and remote automatic control; Increase the voltage and the current automatic locking feature in the empty / load test, and not only improve the security and accuracy of the test system, but also greatly improve the automation of the test system.

Abstract: The study of tracking algorithm of moving objects is a key technique in computer vision; therefore, the work done by this thesis has important theoretical significance and wide practical value. An algorithm based on the improved three-frame-differencing is introduced in this paper. Firstly, three continuous edge images are obtained by edge extract from three continuous images, then, the motion information is detected with three-frame-differencing, finally, the target is extracted by threshold segmentation and morphology. The method is simple in calculation. The experimental results show that the strong robustness and can accurately detect the moving target. In addition, using the algorithm based on the characteristics of the objects can clearly record the object’s trajectory. Experiments show that the algorithm is effective and feasible in the motion object detection.