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There are a large proportion of rear end collisions in a road accident. Based on high level brake lights, the authors developed a set of warning system to reflect the size of the braking force of the front moving vehicle. The rear moving vehicle would be correctly understand brake intention of the front moving vehicle according to vivid, intuitive and timely high level light signal. Thus, the following vehicle would take appropriate measures promptly according to further reduce the probability of rear-end collision accidents.

The 2 mm sheet of 6082 - T6 aluminum alloy was carried to develop refill friction stir welding and withdrawing friction stir spot welding,the forming of solder joints , the cross-sectional microstructure and fracture morphology of welding joints were observed and analyzed, the cross-sectional microhardness of welding joints were tested. Tensile shear load and fracture mode were contrasted simultaneously. The results showed that smooth surface and free of macroscopic defects of welding joints could be obtained in both welding type. Tensile shear load of WFSSW was up to 10.28kN under the optimal process parameters greater than RFSSW’s 8.62kN.

Curve or contour correspondence has been extensively explored. Previous work was mainly concentrated on the rigid correspondence or alignment. This paper presents a spectral analysis method to resolve the problem of curves correspondence with non-rigid deformation. Using the embedding of original affinity matrix to the spectral domain, we can build the point correspondence of no-rigid deformation shapes.

Based on average loading assumption, a non-linear contact finite element model of coupling triple-diaphragm assembly configuration is established. In accordance with the result of diaphragm equivalent stress, the yield strength criterion and high cycle-stress fatigue life norm are adopted to calculate strength safety coefficient and fatigue life of coupling diaphragm. The durability of coupling diaphragm is proved enough numerically.

Based on uniform design, finite element simulation of dieless tube hydroforming and double-screening stepwise regression method, a many-to-many polynomial regression equation set was established, whose independent variables are time t1 at which axial compression displacement from 0 reaches 25mm and time t2 at which internal pressure from 0 achieves 65MPa in 60 seconds, while dependent variables are hoop plastic strain s11 and radial plastic strain s22 in the midmost position of hydroformed tube. Analysis of partial correlation coefficient indicates that the effect of t2 on s11 is a little stronger than t1 and there is no interaction between t1 and t2 on s11, while s22 is influenced by t22 and t1t22. The many-to-many regression model not only quantificationally describes the action of loading factors on plastic strains but also reflects the inherent relevance between plastic strains, which is more useful than several one-to-many regression models to solve problems such as loading characteristic analysis, loading parameters design and optimization, etc.

This paper is about structure optimization of agricultural vehicle frame which adopts the method of adding strengthen box ,set up Frame and strengthen box parameterized mode Based on APDL , Using the optimization module of ANSYS to optimize the shape of the box and place got obvious improvement to the bad stress of longitudinal beam,Thus the overall performance of the frame is improved.

To enhance the utilization efficiency of water and fertilizer resources, and improve agricultural ecological environment in resettlement area, a crop planting structure optimization model was established by the use of multiple objective linear programming (MOLP) method, and solved by two-phase algorithm. In this model, multiple targets, such as the economic, social and ecological benefits of this region were taken into account. The results showed that the MOLP model and its solution were feasible and practical. The optimized area of rice, corn and tobacco reduced by 16%, 100% and 76% respectively, and the optimized area of wheat and sugarcane increased by 82% and 78% compared with the current planting area. And the net economic and social benefits increased by 4% and 62%. The optimization scheme played a guiding role in the adjustment of agricultural structure, and promoted the sustainable development of agriculture in resettlement area.

211Z is a new type of high strength and toughness Al-Cu-Mn casting aluminum alloy. With the aid of GPS-100 high-cycle fatigue testing machine and DDL100 multifunction tensile testing machine, conventional mechanics performance tests and high-cycle fatigue tests were carried out in this paper. The conventional mechanical property results show that the tensile strength is 477.5 MPa, the theory yield strength is 397.5 MPa and the elongation is 6.625%. Fatigue experiments were performed with load control at room temperature and R =-1 in ambient air. The tensile and compression fatigue strength is 130 MPa under ten million times fatigue test, and S-N fatigue life curve of this alloy was also given in the investigations. 211Z casting aluminum alloy possessing high fatigue strength can be attributed to the fact that it owns high strength and good plasticity simultaneously. The microstructure analysis of fatigue fracture appearance shows that, the fatigue crack initiation behavior of this aluminium alloys depends mainly on the region possessing defects under the surface, there has only one crack source, which means it is belongs to low nominal stress unidirectional bending. In the crack growth stage, the width of fatigue striations decreases with the increase of stress, and a few secondary cracks were found in this stage. When cracks finally losed stability, an instantaneous fracture occured in the investigated samples. Shear lips and dimples were found in the fracture appearance and the final fracture is belongs to ductile fracture.

We aimed at high speed machining center high machining accuracy and lightweight design requirements ,Then design the two different stiffened plate structure workbench, The one use traditional design method, the other use bionic design method; Optimize the dimensions of bionic stiffened plate design based on CAD/CAE system integration and hierarchical optimization techniques, got the optimal size; through the static analysis and modal analysis verify the superiority of the optimization schemes.

With the development of social and economy, and the large demand for geospatial information, GIS and GPS technology have deeply penetrated into the areas of land resources, logistics and urban management. Therefore, the research on the position drift of GPS single point and improving the accuracy of positioning data by relatively low cost GPS module, to make the low cost products acquiring position information in high precision has a high practical value for meeting the demands of Low-precision navigation and agricultural survey.

This paper develops an algorithm for extracting stereolithography (STL) model from axisymmetric solid finite element (FE) mesh, so as to use 3D physical prototype instead of computer graphics-based visualization to express the deformation result of FE simulation. The key of the algorithm is to recognize contour node pairs from an axisymmetric solid element mesh, which exactly demonstrates that the proposed methodology is independent of axisymmetric element configuration, that is to say, it is applicable for either triangular, quadrilateral, or mixed triangular and quadrilateral axisymmetric solid element mesh.

An ultra-wideband (UWB) printed antenna with dual band-notched characteristic is presented in this paper. The proposed antenna is composed of a semi-circular patch fed by a tapered coplanar waveguide (CPW) and an unclosed ground plane, which are printed onto the same side of a FR4 printed circuit board (PCB) with an overall size of 30 mm × 30 mm × 1.5 mm. By embedding a simple arc-shaped slot in the patch and adding a T-shaped strip on the top of the patch, two notched frequency bands for rejection of WiMAX and WLAN system can be realized. The characteristics of the proposed antenna are investigated by using the software HFSS and validated experimentally, both simulated and measured results show that the proposed antenna prototype achieves good impedance matching over an frequency band from 2.1011.40 GHz for VSWR2 with two notched bands over the frequency range of 5-5.95 GHz and 3.1-3.9 GHz. Furthermore, a relatively stable gain and suitable radiation patterns are also achieved in both lower and upper UWB frequency band.

Trucks play a significant role in transporting freight through the ground transportation systems, and it is important to be able to estimate and predict the amount of freight in a highway network. In this study, truck weight and volume data, obtained from Weigh-in-Motion stations in California, are analyzed to examine temporal and seasonal patterns. Then coupled with socio- economic variables, a hierarchical regression model is established for estimating freight demand. The model reveals that truck freight demand can be estimated by the truck annual average daily traffic along with the population, number of firms and median income at that county level. What is more, it has a predicting capability of freight weight where no truck weight data is measured. Therefore it can be served for practitioners to predict the growth of freight demand in a freeway network, and is useful to achieve the optimal flows design of cargo at all segments, regardless of whether or not weight data is available.

The purpose of this study is the use of linear array CCD laser sensors to measure the vertical displacement. In this paper, the laser vertical displacement measurement principle of line array CCD has been discussed, using the vector method to calculate the spherical optical ray tracing, and linear CCD laser collimator lens and camera lens are designed.

Lane departure warning system is an important element in improving driving safety and the main difficulty of which is to detect and recognize lane markings quickly and precisely. In this paper, for satisfying the quickness and precision requirement of recognizing lane markings, a novel vision-based lane markings detection and recognition method, which mainly comprise of two steps, is proposed. The first step of which is to roughly determine the ROI of lane markings by means of projection, while the next is to precisely detect lane markings by combining Hough transform with the least square method to fit straight-line. Large amounts of experiment indicate that the proposed method can rapidly and precisely recognize lane markings from sequential images.

This paper established a neural network based on Bayesian regularization, which was used for temperature prediction of feature points in friction stir welding metal. Sample data included rotation speed, welding speed, distance, depth, time and temperature of feature points. The representative sample data was obtained through the orthogonal experiments. Neural network was improved by Bayesian algorithm, and the constraint term representing complexity of network was introduced into the objective function. Then generalization ability of neural networks has been enhanced. Prediction accuracy, training time and stability of network are better than in the traditional neural network. Test proved that this smaller network model operates faster, and it can accurately predict the temperature of feature points of friction stir welding.