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Robust data association is a core problem of visual odometry, where image-to-image correspondences provide constraints for camera pose and map estimation. Current state-of-the-art visual semantic odometry uses local map points semantics, building semantic residuals associated with all classes to realize medium-term tracking of points. Considering the problem of inefficient semantic data associations and redundant semantic observation likelihood model in the visual semantic odometry, we propose a visual odometry, Local Semantic Odometry (LVSO), which is integrated with medium-term semantic constraints based on local nearest neighbor distance model.

To solve the problems of ethnic size difference and model simplification in existing research, three kinds of lower limb finite element models of adult male with percentile 5, 50 and 95 were established based on the size characteristics of Chinese human body.The bionic reliability of the models was verified according to three different lower limb biomechanical experiments. Through the simulation analysis of pedestrian lower limb with different percentiles in side impact, it was found that in the pedestrian low-speed side impact accident, the lower percentile human body has a higher risk of lower limb injury,especially the injury of knee joint. The soft foam structure can play a better cushioning and energy absorption role in the impact process. The response parameters decrease with the decrease of percentile.In addition,the soft foam can significantly reduce the risk of lower limb injuries when impacting the lower limbs laterally at low speed.

As the power of electric vehicles (EVs), lithium-ion batteries (LIBs) are subjected to a variety of mechanical loads during electrochemical operation. Under this operating environment, lithium-ion batteries are at risk of internal short circuit, thermal runaway and even fire, threatening the safety of electric vehicles. The purpose of this paper is to investigate the mechanical behaviors and failure mechanisms of the battery separator to improve the safety of lithium-ion batteries under mechanical loads. In this study, uniaxial tensile, through-thickness compression and biaxial punch tests were performed to characterize two types of separators, dry-processed polypropylene (PP) separators and wet-processed ceramic-coated separators, and to analyze and compare their mechanical properties and failure modes. The comprehensive mechanical tests show that the failure modes of the different separator types are different, with the more anisotropic separator having more complex failure modes.

At present most of software in styling and design, no matter single or integrate, utilize the spline curve as their basis method of surface creating. And the NURBS technology is applied broadly. However, considering the computing time, system resource, and in order to create high quality surface model quickly, the paper brings out and describes the PDE method and its application to surface modeling. PDE, that is partial differential equation, is a numerical method to solve boundary question. The paper will discuss the approach and its application in the following aspects: (1) Application type of the PDE in engineering; (2) Method to control surface shape; (3) Definition the boundary conditions; (4) Managing the CO four side face; (5) Managing the C1 four side face (6) Tackling the triangle face; (7) Interface of PDE to NURBS. The PDE method has many computing techniques, it is easy to write program, and the surface created using this method is smoother than the conventional method.

With rapid progress of information technology, computer has been applied broadly and heavily into automobile panel design and manufacturing. In order to survive in the market and meet various demands of customers, the paper brings out about the integrated design method that considers the whole life cycle of part development and makes data flow fluently between part modeling and die machining. CAD model is very important in the product defined digital model. This gives a summary of panel modeling process based upon the point of application and many examples. There is a detail description on some important issues relevant with part modeling such as modeling types, key techniques and challenges. The panel dies have serious effect on the part quality and design to consistency. It is necessary to define the features respectively and append machine feature to the design features, so that CAM module can read CAD data directly and make the integrated design reality.