Applied Mechanics and Materials Vol. 483

Abstract: Light shape detection of headlamps is an important project of yearly check. In the aspect of lowbeam detection, it is necessary to not only accurately calculate the boundary between brightness and shade, but also optical axis intersection point. By the principle that the second derivative indicates the concavity and convexity of functions, a polynomial fitting is used to calculate the columns grayscale profile of a lowbeam figure, and then get the cut-off point through second derivative of a polynomial. The boundary between brightness and shade is consisted of these cut-off points. The optical axis intersection point is obtained by second order difference of the boundary. While fully extracting graphic features, the method precisely locates positions of the boundary and the intersection.

Abstract: Electrical resistance tomography (ERT) and electrical capacitance tomography (ECT) are sensitive to resistivity and permittivity distributions of the object to be imaged. However, it is hard to discriminate oil, gas and water phases only using ERT or ECT. In this paper, image fusion based on ERT and ECT reconstructed images was investigated for oil-gas-water three-phase flow. And then, pixel-based image fusion method was presented. Simulation results showed that the cross-sectional reconstruction images of oil-gas-water three-phase flow can be obtained using the presented methods for discussed cases.

Abstract: The signal acquisition system (SAS) operated by battery is designed in this paper. SAS includes signal acquisition and statistics function based on movement joints of basketball player. SAS is a recording of the electrical activity of the brain and pulse from the scalp and the recorded waveforms provide insights into the dynamic aspects of brain activity. The amplified SAS signals are digitized by an A/D converter. The digitized signal is transmitted to PC by a wireless serial port or stored in secure digital memory card. Experimental result shows that the system could implement the acquisition and storage of the foot compressive mechanical characteristics signals efficiently. This system would be of benefit to all involved in the use of SAS for sports training.

Abstract: Vibration signal of asynchronous motors are detected with multiple sensors and used to identifying multiple faults of motors in this paper. Independent components analysis method (ICA) is applied to compress measurements from several channels into a smaller amount of channel combinations and separate related vibration signal from interfering vibration sources, and support vector machine (SVM) based multi-class classifiers are used to identify multiple faults of asynchronous motors. Adventures of the proposed methods are that they are data-based and are not necessary to build an analytical model, and SVM-based identification can provide better performance with few datasets. Experiment results are provided to illustrate the performance of the detection and identification methods.

Abstract: The cantilever fluid conveying pipe which restrained by linear spring and cubic nonlinear spring at its free end was studied and the nonlinear vibration of this piping system was carried out optimal control making use of piezoelectric patch as actuator. Firstly, the governing equations of the controlled system were derived out. Then the optimizer and mode sensor were schemed out. Finally, the control effect of the designed controller on system vibration was validated and analyzed through numerical simulation. The simulation results showed that the designed optimal controller can actualize effective control for the monocyclic motion, multi-cyclic motion and chaotic motion of the pipe conveying system. Meanwhile, the effect of state weight-matrix and control energy weighing coefficients on control performance of system, the influence of the position and length of piezoelectric patch on minimal performance index of system were also been under discussion. For practical application of this control method, we should synthetically consider all of the practical conditions and demands to select the optimal position and length of piezoelectric patch and the optimal weight value of state matrix and control energy according to different work conditions.

Abstract: The paper researches on the comparison of two metrics methods under Riemannian metric and under Log-Euclidean metric respectively. Firstly, Experiments are done for comparing the distance and mean values worked out under the two metrics. And the time required for computing under these two metrics is also shown. Lastly, the two methods are applied to the field of image tracking. The performance of the two methods is compared, and the time required for tracking each frame is gained. Experiments results show that the two methods can gain similar distance and mean values, and similar tracking results, while the time required under Log-Euclidean metric is less than under Riemannian metric.

Abstract: The performance simulation and optimization of electric transmission and drive system for multi-axle heavy off-road vehicle is studied. The simulation and optimization model of electric transmission and drive for 10*10 FWD of vehicle are established in CRUISE. And then the optimal preformation and parameters of the system components are obtained.

Abstract: With the application and promotion of large-scale biogas project, economic analysis and evaluation of large-scale biogas project are particularly important. However, the benefits of biogas project embodied in the economic, social, ecological, and many other aspects have dispersion, which leads to production decisions in a gray state and investment in conformity. In this paper, the biogas project in Zhuangda village, Zhaozhou County, Heilongjiang province is taken as an example, the supply and demand of funds in project operation are analyzed quantitatively by using system dynamics theory so as to study the economics of biogas project comprehensively, which can provide scientific guidance for evaluating the construction and operation of large and medium-scale biogas project objectively and lay a solid theoretical foundation for the commercial operation in biogas industry.

Abstract: The design optimization of tolerance is researched to improve the robustness of plane dimension chain. The nonlinear functional relationship between the closed loop and the component loops of a dimension chain is formulated. The tolerances of component loops are regarded as design variables. The total manufacturing costs of the component loops and the success rate of assembly of the closed loop are treated as constraint conditions. Then, a robust design optimization model is established to minimize the variance of the closed loop and to make the mean value of the closed loop approach to target value. The evidence theory is used to deal with the constraint condition on the success rate of assembly. The dimension chain of a gear box is taken as an example to illustrate the proposed method and the example shows that the proposed method is effective.

Abstract: The principle and main steps of module partition in green product configuration design under uncertainty, and how to determine the correlation between the basic elements of a product, and how to calculate the green degree of module are discussed in this paper. Let the maximum degree of cluster inner a module and the minimum coupling degree among modules and the maximum green degree of modules as the objective function, the mathematic model of uncertainly optimizing for green module partition is set up. And then It is transformed to an ascertainable combinatorial optimization model by de-fuzzy operator, and it is solved by GA (Genetic Algorithm,). The methods of chromosome encoding and the methods of selection and crossover and mutation operator are presented in this paper. A computational example is studied; its result verifies the effectiveness and practical value of the method proposed in this paper.