Applied Mechanics and Materials Vols. 63-64

Abstract: In this paper, we proposed an improved texture compression method for graphics hardware. We first give a detail introduction for the texture compression methods which are popular now. Then, an MIPMap-based texture compression method is proposed that is hybrid compression scheme. For smooth area, we can only use 2Bytes to represent the 4*4 pixels block by bilinear interpolation. Otherwise, we will use iPACKMAN algorithm to deal with the noise areas. Actually, this method is feasible to be implemented by hardware since it is very simple. Experimental results show that our method can achieve high compress ratio and high image quality.

Abstract: In this research, a new method based on EMD and SVM for mine fan fault diagnosis is introduced. With EMD, fault feature can be extracted quickly and accurately, and taken as the input samples for SVM with the outstanding non-linear pattern classification performances. 5 two-class SVM classifiers are designed in order to classify and diagnosis 5 typical fault patterns of mine fan. The result of this research shows that the integrative method of EMD and SVM is very fit for the intelligent diagnosis and fault patterns recognition, and it will lead to the possible development of an automated and on-line mine fan condition monitoring and diagnostic system.

Abstract: With the economic development and the improvement of living standards, the demands for the excellent quality fruits grow quickly, while fresh fruits are restricted by the region and season, transportation plays an important role in it. Vibration causes fruits mechanical and physical damage during transportation and affects the fruits storage characteristics and sales. This paper selects Huangguan pear as the research object, using frequency spectral density curve simulates the vibration damage condition of the Huangguan pears in cartons during the actual transportation. Through the simulation results analyze the damage level under the conditions of different packaging forms and different situations and different stacking, and then analyze the relationship of the vibration damage and the other factors. Finally the paper puts forward the Huangguan pear packaging improvements.

Abstract: This paper summarizes the structural optimization applications in civil engineering design and development of the situation based on the characteristics of the bridge structure design process is proposed for the bridge project to the genetic algorithm, neural network, expert system technology as the basis for combining automated design and optimization of structural design of the system; as basic idea, given the structure design of automation system design and optimization of the overall design framework, and prestressed beam design automation is simply an example of structural design and optimization of design automation. Finally, a brief summary of the development process of bridge design software, design automation and optimization that the inevitable trend of development.

Abstract: This paper summarizes a variety of designing and calculating methods of Small and Medium Single-box Multi-room Continuous Box Girder bridge system that used widly in bridge engineering in current. On the basis of careful research and comparison on a variety of designing methods, this paper proposes the advantages and disadvantages of these calculating methods in practical application of theory, proposes the important insights about the developing and perfection direction in the calculating methods, shows clearly the direction on the further research of the designing and calculating methods of the Small and Medium Single-box Multi-room Continuous Box Girder Bridge.

Abstract: The measurement of low and ultra-low frequency vibration has always been a very difficult problem. In this paper, a new structure is designed and a new type of low and ultra-low frequency accelerometer is developed by using a sensitive element PVDF. A new type of sensor structure and working principle are discussed and mathematical model and characterize are analyzed in this paper. The result confirmed that this design method can improve sensitivity, precision and performance of the sensor, overcome the acceleration interference of other direction in the vertical axis upwards, and improve the unilateralism and stability of the sensor.

Abstract: We introduce an improved compressing algorithm with features reserved for point cloud. Divided-box method is employed for compressing algorithm to improve the neighbor field searching efficiency, with which normal vector and curvature of points are calculated, and feature points are reserved according to reducing rule, finally, based on the octree theory, the smallest grid is refined until which reaches the minimum requirements, then reserve the most representative point of the smallest grid, remove the other points, and data reduction is done. Experimental results show that the compression algorithm conserved the features of point cloud with high efficiency.

Abstract: In order to accurately reflect the effects and the spatial and temporal variation of long span cable-stayed bridge during the construction process, this paper, based on total CR formulation and the catenary cable element, improves the existing methods of geometrically nonlinear analysis and then develops a new software for nonlinear analysis of bridge through the entire construction.

Abstract: By the universal testing machine and special fixture, the leaf spring suspension was tested for deformation, and based on nonlinear finite element theory, the suspension was analyzed. The calculation result is coinciding with test result.The finite element model established could be applied to design calculation and parameter optimization of leaf spring suspension.

Abstract: This paper uses a rear sub-frame as the mother model and uses Reverse engineering technology to measure the rear sub-frame point cloud through ATOS non-contact scanners. Then, the point cloud‘s data processing is completed in Imageware. Finally, the point cloud is imported into UG NX4.0 software, after a series of surface cutting, chamfer suturing and sheet thickening; the sub-frame’s three-dimensional model is established. Besides, we complete the static finite element analysis and modal analysis of the sub-frame’s three-dimensional model through the ANSYS software. The results of analysis support theoretical basis for the structural improvement of sub-frame.