基于STM32的视频流图像更新方法的研究

对基于STM32系统低速(工作主频72MHz)视频流处理显示更新方案的研究。结合图像处理基本理论,分析传统的显示方法的不足,并提出一种新的视频流图像更新的方法,通过一定的实验数据和理论结果,验证该方法可行性。     

A shortcut to marking 3D target curves on curved surface via a galvanometric laser scanner

Marking arbitrary three-dimensional(3D) target curves on given objects with curved surface is required in many industrial fields, such as fabric prepreg placement in composite material part fabrication, product assembly, surface painting for decoration, etc. A shortcut to the solution of this intractable problem is proposed by utilizing a galvanometric laser scanner(GLS) with the aid of a camera. Without using the existing tedious GLS calibration procedures,the proposed method directly establishes a mapping between the 3D coordinates of the laser spots on the object surface and the control voltages of the scanner. A single-hidden layer feedforward neural network(SLFN) is employed to model the mapping. By projecting a dense grid of laser spots on the object to be marked and simultaneously taking only one image, the SLFN model is trained in minutes via a linear solving mechanism. Experiments demonstrate that the trained SLFN model has a good generalization performance for marking 3D target curves. The 3D laser marking errors on experimental objects are less than 0.5 mm. The proposed method is especially suitable for on-site use and can be conveniently extended to multiple GLSs for marking large complex objects.     

复合材料构件热压罐成型温度场研究

在热压罐固化工艺的热历程中,复合材料零件表面温度场分布的合理与否将直接决定产品的固化质量.以工字型零件和T型加筋壁板两种复合材料零件为研究对象,使用EC-3×8M和SCH-5.5×21M两种型号热压罐,同时选择炉温偶和零件偶两种控温方式对零件进行固化.通过分析温度场测试结果发现,控温方式、设备加热方式、升降温速率、热电偶的摆放位置、固化压力等因素均对零件的温度场有影响.     

Mining Spatial Associations with Limited Sensory Information

Abstract

Human navigation in an unknown environment requires an understanding of the spatial relationships of the terrain. For example, a soldier who is on a reconnaissance mission in a new city needs to “know” the spatial layout of the surroundings with high confidence. Oftentimes, this understanding must be acquired within a very short amount of time and with limited sensory inputs. The soldier would benefit from a digital avatar that draws inferences about the spatial layout of the city based on an initial set of observations and guides the soldier either in further exploring the environment or in making decisions based on these inferences. In this paper, we present and evaluate an inductive approach to learning spatial associations using sensory data that is available from the simulation environment of a computer game, Unreal Tournament. We study two kinds of spatial relationships between nodes on a level of a game map: nodes that are placed near each other to satisfy some spatial requirement and nodes that are placed near each other to satisfy the design preferences of a level architect. We show that we can infer both kinds of relationships using an association rule mining algorithm. Furthermore, we show how to use an ontology to distinguish between these relationships in order to discover different types of spatial arrangements on a specific map. We discuss how the inferred associations can be used to control an avatar that makes recommendations for navigating unexplored areas on a map. We conclude with some thoughts on the applicability of our methods to scenarios in the real world, beyond the simulation environment of a game, and on how the learned associations can be represented and queried by a simple question-answer type system.     

软件无线电概念及直接中频采样软件接收机方案

软件无线电是最近几年提出的一种实现无线电通信的新的体系结构，文章介绍了软件无线电的概念、特点、历史和现状，并且提出和分析了直接中频采样软件接收机实现方案。     

EBE技术在结构分析中的应用（Ⅰ）─EBE矩阵向量乘积方法及其实现

矩阵向量乘积运算是数值分析领域中的一种基本运算。本文基于单元分组技术，提出了在有限元结构分析中，当不形成总刚度矩阵而进行矩阵向量乘积的ＥＢＥ计算方法。该方法不仅预处理过程简单，实现容易，而且其并行化、向量化处理都极为直接。同时，数值试验结果还表明了它的有效性。     

Multifractal Spectrum and Calculation

多重分形理论是进行信号奇异性处理的有用工具 ,由于只有少数集合的多重分形谱可以有解析表达式 ,多重分形谱的计算是其中重要而又较难处理的问题 .简要介绍了多重分形理论的一种形式体系 ,提出了一种采用动态链表来进行多重分形谱计算的方法 ,大幅度地降低了对存储器容量的要求 .用所提出的方法对康托集进行了计算 ,计算结果与理论结果相符 ,表明了算法的有效性 .     

椭圆的数控加工宏程序编制

根据华中世纪星数控系统及固定循环指令特点,将椭圆型腔的粗加工、精加工程序编制成固定循环格式,用户在加工过程中只需要用指令调用即可。这样在加工过程中大大缩短程序编制时间,提高数控宏程序的集成度,使数控机床高效、高精度的潜力被充分挖掘。     

一种团块位置的提取方法

如何正确提取团块位置以实现自动跟踪对图像理解有重要意义。由于团块在图像中出现频繁且位置不确定，位置提取困难。针对一个二值图像识别系统提出了基于集合变换（即数学形态学和二值有序统计）的团块位置提取方法。即，首先对图像进行二值化，其次对二值化图像进行形态学变换，最后对变换的结果图像进行统计分析，由分析结果得出团块的位置信息。用本方法对地图中九种团块线型作了实验，表明该方法运算简单，并行性高。