弯曲木的热定型技术

本文对木材顺纹压缩多维弯曲技术中的热定型方法进行了详细的探讨,并分析了各种定型机理。通过比较直接干燥定型、水热干燥定型和微波干燥定型的方法以及快速检测其定型效果的手段、得出微波干燥定型的效果好于前两者。     

多向聚能爆破爆破漏斗实验研究

多向聚能爆破是一种新型爆破技术。为研究多向聚能爆破在爆破漏斗上能量分配特点,在阐明多向聚能爆破基本原理和影响因素基础上,设计了多向聚能爆破药包,进行常规爆破与多向聚能爆破的爆破漏斗体积对比实验。结果表明,多向聚能爆破能够增加爆破漏斗体积并提高了爆炸能量在岩石破裂破碎方面的分配比例,提高了炸药利用率。     

Stereo matching based on multi-direction polynomial model

This paper presents a segmentation based stereo matching algorithm. For the purposes of both preserving the shape of object surfaces and being robust to under segmentations, we introduce a new scene formulation where the reference image is divided into overlapping lines. The disparity value and the index of pixels on lines are modeled by polynomial functions. Polynomial functions are propagated among lines to obtain smooth surfaces via solving energy minimizing problems. Finally, the disparity of pixels is estimated from the disparity fields provided by lines. Because lines in multiple directions implicitly segment different objects in an under segmentation region, our method is robust for under segmented regions where it is usually difficult for conventional region based methods to produce satisfactory results. Experimental results demonstrate that the proposed method has an outstanding performance compared with the current state-of-the-art methods. The scene representation method in this work is also a powerful approach to surface based scene representations.     

Automatic multi-direction slicing algorithms for wire based additive manufacturing

One of the key challenges in Additive Manufacturing is to develop a robust algorithm to slice CAD models into a set of layers which requires minimal support structures. This paper reports the concept and implementation of a new strategy for multi-direction slicing of CAD models represented in STL format. Differing from the existing multi-direction slicing approaches that are mainly focused on finding an optimal volume decomposition strategy, this study presents a decomposition-regrouping method. The CAD model is firstly decomposed into sub-volumes using a simple curvature-based volume decomposition method. Then a depth-tree structure based on topology information is introduced to merge them into ordered groups for slicing. In addition, a model simplification step is introduced before CAD model decomposition to significantly enhance the capability of the proposed multi-direction strategy. The proposed strategy is shown to be simple and efficient on various tests parts especially for geometries with large number of holes.     

单轴线挤压铸造凝固组织形态和塑性变形缺陷分析

分析了单轴线挤压铸造凝固体内部正向和径向压力存在的差异。结果表明,正向压力沿轴线分布同样不均匀,压力差异使得界面传热系数、结晶前沿熔体温度梯度、晶体生长速度以及塑性变形出现差异,产生单轴线挤压铸造件凝固组织形态不一致、致密度不均匀等缺陷。提出了一种满足组织性能均匀、高致密等要求的高性能铸件的多向挤压铸造工艺方法。     

多向聚能爆破爆破漏斗实验研究

多向聚能爆破是一种新型爆破技术。为研究多向聚能爆破在爆破漏斗上能量分配特点,在阐明多向聚能爆破基本原理和影响因素基础上,设计了多向聚能爆破药包,进行常规爆破与多向聚能爆破的爆破漏斗体积对比实验。结果表明,多向聚能爆破能够增加爆破漏斗体积并提高了爆炸能量在岩石破裂破碎方面的分配比例,提高了炸药利用率。     

多元多向抽芯塑料盒注射模具设计与分析

主要介绍了多元多向抽芯塑料盒的成型工艺及模具结构特点；并详细分析了模具的动作原理和过程，为类似产品注射模具的设计提出了一条新的思路。     

面向边缘反走样的屏幕内容索引图自适应预测

由于边缘反走样区域的相邻索引不具备等值关系,调色板编码的预测效率有限,因此文中提出基于边缘反走样决策和多方向模板的自适应预测编码方法.引进Pitteway面积加权的边缘反走样决策,设计8个4-邻域方向预测模板.利用2D线性相关模型建模待预测索引与4个参考像素之间的相关性.采用最小二乘法为每个方向模板计算一组预测权重系数,自适应地学习显示适配器的边缘反走样算法,实现索引图预测编码.实验表明,文中方法预测准确率较高,能够增强调色板编码在边缘反走样区域和复杂边缘区域的自适应预测能力.