基于ZigBee的工业控制网络模型

将无线传感器网络技术成功应用于工业自动化,建立了基于ZigBee的工业控制网络模型,并成功应用于生产线的工业控制中.     

Improving iris recognition performance via multi-instance fusion at the score level

Fusion of multiple instances within a modality for biometric verification performance improvement has received considerable attention. In this letter, we present an iris recognition method based on multiinstance fusion, which combines the left and right irises of an individual at the matching score level. When fusing, a novel fusion strategy using minimax probability machine （MPM） is applied to generate a fused score for the final decision. The experimental results on CASIA and UBIRIS databases show that the proposed method can bring obvious performance improvement compared with the single-instance method. The comparison among different fusion strategies demonstrates the superiority of the fusion strategy based on MPM.     

基于无线网络的塔吊群防碰撞系统的研究

根据无线网络的特点与塔吊群协同作业的安全要求,研究了工业环境下无线网络的实时性和可靠性,成功研制了塔吊群防碰撞系统,预防塔吊间的碰撞问题.     

Fast algebra algorithm of shape-from-shading with specular reflectance

Shape-from-shading (SFS) is to reconstruct three-dimensionai (3D) shape from a single gray image,which is an important problem in computer vision.We propose a novel SFS method based on hybrid reflection model which contains both diffuse reflectance and specular reflectance.The intensity gradient of image is in the direction that the shape of surface changes most,so we use directional derivative of the reflectance map as parts of objective function.When discrete characteristic of digital images is considered,finite difference approximates differential operator.So the reflectance map equation described by a partial differential equation (PDE) turns into an algebra equation about the unknown surface height correspondingly.Using iterative numeric computation,a new SFS method is gained.Experiments on synthesis and real images show that the proposed SFS method is accurate and fast.     

复杂X光照条件下非凸表面完全重构

针对复杂光照条件下非凸表面完全重构问题,提出了一种基于两步策略的多目重构新方法.把立体匹配过程转化为颜色方差最小化问题,利用颜色方差阈值来平衡采样点数与采样噪声之间的矛盾,同时回避了立体匹配算法的二义性.采用水平集方法建立曲面运动方程,通过符号距离函数的演化过程逼近目标表面;通过弹性势能的最小化过程滤除采样噪声,增强对遮挡、光照条件的稳键性.实验结果表明,该方法能够在复杂光照条件下推断出非凸目标形状,且与Jin的算法比较,表现了更好的准确性,节省31%～39%的重构时间.     

A polynomial hybrid reflection model and measurement of its parameters based on images of sample

Reflectance model is a basic concept in computer vision.Some existing models combining the classical diffuse reflectance model and those for surfaces containing specular components can approximately describe real reflectance.But the ratio of diffuse and specular reflection decided manually has no clear meaning. We propose a new polynomial hybrid reflectance model.The reflectance map equation with a known shape (for example cylinder)as a sample is used to estimate parameters of the proposed reflectance model by least square regression algorithm.Then the reflectance parameters for surfaces of the same class of materials can be determined.Experiments are performed for a metal surface.The synthesis images produced by the proposed method and existing ones are compared with the real acquired image,and the results show that the proposed reflectance model is suitable for describing real reflectance.     

基于多参数模型的非分散红外光谱气体检测稳定性方法研究

针对非分散红外光谱传感器零点和温度漂移问题,建立了一种基于零气光强、参考光强、标准温度、环境温度、温度漂移系数等多参数模型,对红外传感器长期连续运行中存在的零点和温度漂移进行自动校正和补偿。测试结果和长时间应用表明,仪器在各种变换的环境条件下检测精度均小于5%F.S。CO₂的平均检测精度从未综合处理前的9.26%提高到了处理后的1.23%,CH₄的平均检测精度从未综合处理前的10.61%提高到了处理后的0.70%,克服了很多气体检测仪存在的稳定性差,标定周期短等不足,有效提高了仪器的检测精度、稳定性,降低了维护成本。