基于兼容性网格分割的骨骼参数计算

为了解决骨骼参数难以测量的问题,提出一种利用网格分割结果计算参数的方法.首先对骨骼网格模型在提取少量特征点的基础上进行语义分割;然后将分割得到的模板借助基于Laplacian变形的非刚性配准,指导同类骨骼模型实现快速兼容性分割;最后结合网格分割结果及特征点计算出骨骼的主要形态参数.实验结果表明,该方法仅需少量的用户交互就能获得较好的测量效果,结合模板的策略也支持大批量骨骼模型的参数测定.     

Multifocus image fusion method of Ripplet transform based on cycle spinning

The curvelet transform can represent images at both different scales and different directions. Ripplet transform, as a higher dimensional generalization of the curvelet transform, provides a new tight frame with sparse representation for images with discontinuities along C² curves. However, the ripplet transform is lack of translation invariance, which causes the pseudo-Gibbs phenomenon on the edges of image. In this paper, the cycle spinning method is adopted to suppress the pseudo-Gibbs phenomena in the multifocus image fusion. On the other hand, a modified sum-modified-laplacian rule based on the threshold is proposed to make the decision map to select the ripplet coefficient. Several experiments are executed to compare the presented approach with other methods based on the curvelet, sharp frequency localized contourlet transform and shearlet transform. The experiments demonstrate that the presented fusion algorithm outperforms these image fusion works.     

基于飞行器网络控制系统的多速率控制器设计

为了减少网络环境中的时延和数据包丢失对飞行器网络控制器系统的影响,设计了一种具有多速率的保性能控制器设计方法;多速率是指在具有多通道数据传输的系统中,各通道所需控制输入的频率不完全相同;在存在时延和丢包的情况下,利用增广技术对飞行器控制系统在整个循环周期内建立离散模型,此时为了使多速率控制方法更加有效,先基于此模型在控制器输入端构造一个预测器,根据预测器的输出为整个系统设计一个具有多控制速率的动态输出反馈控制器;然后给出并证明保性能控制器的存在条件和求解方法;最后通过某飞行器网络控制系统的数值算例验证了所提方法的有效性。     

基于扩展自适应融合算法的GILS进近系统研究

通过研究飞机在低可见视程条件下的进近问题,力图充分利用全球卫星导航系统的能力,使机场在不需要更新陆基无线电导航系统的情况下从I类盲降标准提升到II类及以上的相同或可比拟的运行标准;通过对某航空公司飞行数据的分析,为提高飞机进场水平导航精度和空域利用率,提出了组合应用全球卫星导航系统GNSS(global navigation satellite system)和仪表着陆系统ILS(instrument landing system)的进近体制模型,即为GILS(GNSS and ILS)进近系统;利用扩展自适应融合算法,将两种导航源的定位数据融合,通过数学建模,仿真模拟飞机进近航迹;仿真和实际验证试飞数据表明,该方案可有效提高飞机的水平导航精度和空域利用率,有潜力将CAT I标准提升为类CAT II水平。     

完备自适应近邻图嵌入的局部鉴别投影算法

针对基于自适应近邻图嵌入的局部鉴别投影算法（Neighborhood graph embedding based local adaptive discriminant analysis, LADP ）仅仅利用局部类内离差矩阵主元空间的鉴别信息而丢失了其零空间内大量鉴别信息的不足,结合全空间的基本思想提出了完备的基于自适应近邻图嵌入的局部鉴别投影算法（ Complete LADP,CLADP）。在局部类内离差矩阵的零空间内,通过最大化局部类间离差矩阵提取不规则鉴别特征,在局部类间离差矩阵的主元空间内,通过最大化局部类间离差矩阵的同时最小化局部类 内离差矩阵提取规则鉴别特征,最后将不规则鉴别特征和规则鉴别特征串联形成CLADP特征。在ORL,Yale以及PIE人脸库上的人脸识别实验结果证明了CLADP的有效性。     

Error quantification of the normalised right graph symbol for an errors-in-variables system

This paper proposes a novel method to quantify the error of a nominal normalized right graph symbol (NRGS) for an errors-in-variables (EIV) system corrupted with bounded noise. Following an identification framework for estimation of a perturbation model set, a worst-case v-gap error bound for the estimated nominal NRGS can be first determined from \textit{a priori} and \textit{a posteriori} information on the underlying EIV system. Then, an NRGS perturbation model set can be derived from a close relation between the v-gap metric of two models and ${\rm H}_\infty$-norm of their NRGSs' difference. The obtained NRGS perturbation model set paves the way for robust controller design using an ${\rm H}_\infty$ loop-shaping method because it is a standard form of the well-known NCF (normalized coprime factor) perturbation model set. Finally, a numerical simulation is used to demonstrate the effectiveness of the proposed identification method.     

Quasi-Newton-type optimized iterative learning control for discrete linear time invariant systems

In this paper, a quasi-Newton-type optimized iterative learning control (ILC) algorithm is investigated for a class of discrete linear time-invariant systems. The proposed learning algorithm is to update the learning gain matrix by a quasi-Newton-type matrix instead of the inversion of the plant. By means of the mathematical inductive method, the monotone convergence of the proposed algorithm is analyzed, which shows that the tracking error monotonously converges to zero after a finite number of iterations. Compared with the existing optimized ILC algorithms, due to the superlinear convergence of quasi-Newton method, the proposed learning law operates with a faster convergent rate and is robust to the ill-condition of the system model, and thus owns a wide range of applications. Numerical simulations demonstrate the validity and effectiveness.     

石墨烯/聚赖氨酸修饰玻碳电极测定铅离子

通过聚赖氨酸修饰电极静电吸附氧化石墨烯,并结合电化学还原制备石墨烯/聚赖氨酸修饰玻碳电极。应用Raman光谱确认了通过电化学还原过程可将电极表面所吸附的氧化石墨烯部分地还原成石墨烯。在阳极溶出法测定Pb2+的应用中,所得到的石墨烯/聚赖氨酸修饰玻碳电极较裸玻碳电极表现出较高的响应灵敏度。在1.0～5.0×10-6mol/L浓度范围,响应峰电流与Pb2+浓度呈良好的线性关系。     

浅析计算机网络通讯存在的问题及其改进策略

随着我国的科技事业的快速进步,越来越多的科技项目不断的被研发和生产,其中计算机通信工程的建设和完善始终和百姓的生活有着紧密的联系。在日常生活中,电话、手机已相当的普及,这样一些方面就是得益于通信工程作出突出贡献。该文中,我们将着力介绍计算机网络通讯在运行中存在的问题,以及就这些问题我们提出了相应的建议和改进策略。     

A hierarchical dense deformable model for 3D face reconstruction from skull

3D face reconstruction from skull has been investigated deeply by computer scientists in the past two decades because it is important for identification. The dominant methods construct 3D face from the soft tissue thickness measured at a set of landmarks on skull. The quantity and position of the landmarks are very vital for 3D face reconstruction, but there is no uniform standard for the selection of the landmarks. Additionally, the acquirement of the landmarks on skull is difficult without manual assistance. In this paper, an automatic 3D face reconstruction method based on a hierarchical dense deformable model is proposed. To construct the model, the skull and face samples are acquired by CT scanner and represented as dense triangle mesh. Then a non-rigid dense mesh registration algorithm is presented to align all the samples in point-to-point correspondence. Based on the aligned samples, a global deformable model is constructed, and three local models are constructed from the segmented patches of the eye, nose and mouth. For a given skull, the globe and local deformable models are iteratively matched with it, and the reconstructed facial surface is obtained by fusing the globe and local reconstruction results. To validate the presented method, a measurement in the coefficient domain of a face deformable model is defined. The experimental results indicate that the proposed method has good performance for 3D face reconstruction from skull.