Applied Mechanics and Materials Vols. 541-542

Abstract: This paper presents a novel sensory system for monitoring situations of riding bicycle. The proposed system can be used to measure and save in real-time not only the motion of bicycle rider but also the situation near the vehicle. Multiple inertial sensors being attached to human body are employed to measure the motion of the rider. Two laser scanners installed in the front of the bicycle and two cameras of wide view angle were used to detect the environmental change including pedestrians and static/dynamic objects. The system configuration was designed for the synchronization of multiple sensors according to the position information of the vehicle. Particularly, the human motion of riding bicycle is captured with the system and analyzed with the measurement data in this paper.

Abstract: Water suppression experiments of EPS and XPS are conducted in Standard Combustion Chamber in USTC in Hefei. The 20 cm * 20 cm PSs were held against a 600 mm*600 mm vertical gypsum board fixed by a steel frame structures to simulate a building facade. A series of results have been obtained. When the water spray is not applied, the EPS is easier to melt, drip and pyrolyze than XPS under the same fire load, but causes less amount of CO than the amount of XPS without any water application. When the water is applied, neither EPS nor XPS has a trend to drip. The amount of CO caused by EPS or XPS under water spray is much less than that of non-spray. Also the extinguishment time falls fast once the PS materials are applied with water. In addition, these experimental results demonstrate the feasibility of the designed rig in studying the fire suppression on vertical PS materials using water spray.

Abstract: In order to solve the problem of installation and measuring errors in the profile evaluation of large parabolic antennas, this paper proposes a new method for evaluating the profile of large paraboloidal antennas based on genetic algorithm and least square method. This method can effectively realize the adaptive adjustment of the measured points and the theoretical contour in the process of evaluating profile, which can eliminate the position error between the measured points and the theoretical contour that influences on the results of the profile evaluation. The availability of this method has been proved by simulation.

Abstract: Mechanical reliability testing is the focus in the research of reliability testing at present. The basic concepts of reliability testing are introduced. Names of reliability testing are sorted. Characteristics of mechanical reliability testing are discussed. The key issues of mechanical reliability testing and its development are then reviewed. Finally, some possible fields in the research are summarized.

Abstract: Tool condition monitoring is an important issue in the advanced machining process. Existing methods of tool wear monitoring is hardly suitable for mass production of cutting parameters fluctuation. In this paper, a new method for milling tool wear condition monitoring base on tunable Q-factor wavelet transform and Shannon entropy is presented. Spindle motor current signals were recorded during the face milling process. The wavelet energy entropy of the current signals carries information about the change of energy distribution associated with different tool wear conditions. Experiment results showed that the new method could successfully extract significant signature from the spindle-motor current signals to effectively estimate tool wear condition during face milling.

Abstract: The biggest problems of online monitoring stress for crane currently are the signal stability problem and the high cost problem. Aiming at these problems, the authors design the stability monitoring project for shipbuilding portal crane. The project adopts the wired monitoring method and the strain signal is amplified preliminarily at the measuring point, the combination of both which overcomes the problems of strain signal attenuation and electromagnetic interferences. The acquisition box is reset punctually to avoid the drift problem. An experiment of online monitoring stress for shipbuilding portal crane used for 5 years is done in a shipyard, and the experiment proves that the effective relative error is less than 6%. Compared with the wireless monitoring way, the project costs lower and isnt subject to electromagnetic interferences. Moreover, compared with the traditional wired monitoring way, the program has more stability signal.

Abstract: Vehicle Target Detection and Tracking Method Based on Image Super-Resolution Reconstruction and Variable Template Matching is Put Forward. Firstly, a Nonlinear Iterative Algorithm is Applied to Reconstruct a Super-Resolution Image from Low Resolution Image Sequence; then, the Image is Standardized and the Movement Areas are Determined; Finally, the Variable Template Matching Method is Used to Detect and Track the Vehicle Targets in Movement Areas. from the Characteristics of Algorithm and the Experiment Results, we can see that the Proposed Algorithm Improves the Matching Accuracy of Target Tracking and Better Solves the Limitation of Missed Detection for Traditional Methods. the Reason of the Good Performance of the Proposed Algorithm Relies in High Quality Images Acquired by Super-Resolution Reconstruction from Low Resolution Image Sequence and the Application of Variable Template Matching Method.

Abstract: In this paper, the tracking accuracy of one-dimension north-south solar tracking system is analyzed. The method of indirectly measuring one-dimension north-south solar tracking system is given according to the variation of sun position, and the relevant formulas are derived. The experiment on measuring the relationship between tracking accuracy and thermal efficiency of trough system is also conducted. Experimental results show that the system tracking deviation is 0.04 0.065°; the peak of tracking deviation of trough system is 0.875°.

Abstract: We studied volatile determination in lignite coal samples using near-infrared (NIR) spectra. Firstly, spectra were pre-processed to eliminate useless information. Then, determination model was constructed by partial least squares regression. We used discrete wavelet transform to pre-processing. To study the influence of modeling on determination of volatile for NIR analysis of lignite coal samples, we applied three techniques to build determination model, including support vector regression, partial least square regression and radial basis function neural network. Comparison of the mean absolute percentage error (MAPE) and root mean square error of prediction (RMSEP) of the models show that the models constructed with radial basis function neural network gave the best results.

Abstract: For reasons of low accuracy of artificial survey leakage, a gas pipeline leakage diagnosis method based on BP neural networks and D-S theory is presented by introducing WSN and information fusion theory. Two sub-neural networks are established at normal node to simplify network structure. The leakage characteristic parameters of negative pressure wave and acoustic emission signals are used as input eigenvector respectively for primary diagnosis. Through making preliminary fusion result s as the basic probability assignment of evidence, the impersonal valuations are realized. Finally, all evidences are aggregated at normal and sink node respectively by using the improved combination rules. The method makes full use of redundant and complementary leakage information. Numerical example shows that the proposed improves the leakage diagnosis accuracy and decreases the recognition uncertainty.