Applied Mechanics and Materials Vols. 668-669

Abstract: In this paper, we propose a variety of correlation coefficient measures for hesitant fuzzy sets (HFSs) and investigate their properties. Moreover, we utilize the concepts of correlation relation matrix, composition matrix and equivalent correlation relation matrix to deal with the clustering problem under hesitant fuzzy environment. Finally, a numerical example is utilized to validate the proposed correlation coefficient measures and the clustering method.

Abstract: Local support vector machine gives the feature same weight in classification. In fact, many datasets have some weak or irrelevant features related to the classification. Thus giving features same weight may reduce the classification accuracy of local support vector machine.This paper puts forward a new local support vector machine that the feature weight is optimized by PSO (Particle Swarm Optimization), it is tested on the international standard UCI data sets and the images of tree taxonomy data sets, the results show that the accuracy of the algorithm we proposed is better than the general local support vector machine.

Abstract: In the process of particle filter, it can produce the problem of particle degeneration, and the amount of computation is very big. In order to solve these two problems, this paper presents a method for video redirection parameters optimization based on hierarchical genetic optimization strategy. This paper adopts hierarchical mutation operator and local crossover operator. The result shows that the hierarchical genetic optimization algorithm which is used in video tracking has a very good effect.

Abstract: Equipment performance degradation model is a key component in its diagnosis and prognosis models. As to slewing bearing, vibration signals are usually non-stationary and with strong white noise, which makes it very difficult to extract useful information from the signals. Therefore, an Ensemble Empirical Mode Decomposition – Principle Component Analysis (EEMD - PCA) based method was proposed to denoise the vibration signals and performance degradation model was established by PCA. To verify the proposed method, an experiment was conducted and the life cycle vibration signals were acquired. After denoising, performance degradation model was established to explain the denoising performance. Results show that the proposed method acquired a better denoising performance than EEMD-MSPCA, which provides a potential for further research.

Abstract: To maintain terrain details during contour group simplification, a progressive simplification approach is proposed. First, terrain feature points and lines are extracted from contours. Second, both the extracted terrain feature points and lines are taken as constraints and quantified as control variables. At last with the idea of progressive graphics simplification, the non-feature points, feature points, feature lines and their associated curves on contours are selected or deleted progressively to realize dynamic simplification of contours. Experimental results show that this approach can effectively improve the intellectualized degree of contours simplification.

Abstract: With good repeatability and simple structure, transmission line pulse (TLP) has been used in immunity test of integrated circuit and printed circuit board. A TLP generator is first manufactured and its output waveform is presented. By using wavelet transform, the waveform is denoised and discriminated to components inherent to system function and parasitic parameters. Frequency spectrum changed with time is also obtained by continuous wavelet transform of complex morlet. Decomposed damping oscillation component and high frequency component in instant frequency spectrum show influence of inductance in circuit on the waveform. Improvement of rising time and overshoot is achieved by change of probe connection with shorter grounding line.

Abstract: Nowadays, there have been many data which are represented by tensor, that how to deal with these tensor data directly remains a significant challenge. In this paper, we propose a new tensor distance (TD) based least square twin support tensor machine (called TDLS-TSTM). Unlike the traditional Euclidean distance, TD considers the relationship information of various coordinates. TDLS-TSTM works directly on tensor data and aims to find two nonparallel hyperplanes for classification based on TD which can make full of structural information of data, solves two systems of linear equations rather than two quadratic programming problems. Compared with other classifiers, our method has the advantages of higher precision and accepted time consumption. The numerical experiments show the valid and efficient of TDLS-TSTM.

Abstract: Autonomous off-road navigation is a highly complicated task for a robot or unmanned ground vehicle (UGV) owing to the different kinds of obstacles it could encounter. In-particular, water hazards such as puddles and ponds are very common in outdoor environments and are hard to detect even with ranging devices due to the specular nature of reflection at the air water interface. In recent years, many researches to detect the water bodies have been done. But there still has been very little work on detecting bodies of water that could be navigation hazards, especially at night. In this paper, we used Velodyne HDL-64ES2 3D LIDAR to detect water hazard. The approach first analyzes the data format and transformation of 3D LIDAR, and then writes the data acquisition and visualizations algorithm, integrated data based on ICP algorithm. Finally according the intensity distribution identifies the water hazard. Experiments are carried out on the experimental car in campus, and results show the promising performance.

Abstract: In order to solve the real-time problem in the background motion compensation in video sequence, a kind of quick background motion compensation algorithm based on BRISK operator has been proposed in this paper. Firstly, feature points of two adjacent frames images was extracted and matched by using BRISK operator. Secondly, the motion vector of the neighboring frames images was calculated by using the least square method (LSM). Lastly, the video sequences were compensated by using bilinear interpolation method. The simulation results show that real-time can arrive at ms grade and meet the requirement of background motion compensation.

Abstract: In this paper, variable step-size Adomian Decomposition Method (VADM) is proposed to obtain approximate analytical solution of coupled Duffing oscillators. Using VADM, analytical expressions for two-degree-of-freedom coupled Duffing equations are derived for different amplitude values of external periodic excitation. The system stability is analyzed by analyzing time-domain graph and phase portraits. Compared with the MATLAB@ ODE45, simulation results reveal that VADM is effectively and well suited for nonlinear dynamic system.