基于线性光谱混合模型的光谱解混改进模型

传统的基于线性光谱混合模型(LSMM)的解混方法采用迭代求解方式,复杂度较高,为此提出一种基于几何方式的模型求解方法。另一方面,LSMM采用固定谱形固定数量的光谱端元进行解混,影响了光谱解混精度,为此提出端元谱形的区域修正方法和端元子集的局域确定方法,从而建立基于柔性端元的新解混方式。实验表明了所提出的几何求解方法及柔性光谱端元方式的有效性。     

基于几何估计的光谱解混方法

光谱解混是高光谱数据分析的重要技术之一.全约束(即非负性约束和归一化约束)最小二乘线性光谱混合模型(FCLS-LSMM)具有模型简单和物理意义明确等优点而得以广泛使用.然而,FCLS-LSMM的传统优化求解方法的迭代过程非常复杂.近年提出的几何方法为降低LSMM的求解复杂度提供了新思路,但是所获得的结果并非真正意义上的全约束最小二乘解.为此,建立了一种完全符合FCLS要求的LSMM几何求解方法,具有复杂度低和可以获得理论最优解等优点.实验表明了所提出方法的有效性.     

基于几何估计的光谱解混方法

光谱解混是高光谱数据分析的重要技术之一。全约束(即非负性约束和归一化约束)最小二乘线性光谱混合模型(FCLS-LSMM)具有模型简单和物理意义明确等优点而得以广泛使用。然而,FCLS-LSMM的传统优化求解方法的迭代过程非常复杂。近年提出的几何方法为降低LSMM的求解复杂度提供了新思路,但是所获得的结果并非真正意义上的全约束最小二乘解。为此,建立一种完全符合FCLS要求的LSMM几何求解方法,具有复杂度低和可以获得理论最优解等优点。实验表明了所提出方法的有效性。     

DSC的超光谱图像无损压缩算法

有效的星载超光谱图像压缩技术对于解决超光谱图像实时传输极为重要。针对超光谱图像传统的联合编解码算法的不足,提出了一种基于分布式信源编码(Distributed Source Coding,DSC)的超光谱图像无损压缩算法。为利用超光谱图像的局部空间相关性,将超光谱图像进行分块处理;引入多元线性回归模型构建编码块的边信息,并为每个编码块选取最优的预测阶数,以有效利用超光谱图像的局部谱间相关性。根据(n,k)线性分组码的原理,通过多元陪集码实现超光谱图像的分布式无损压缩。实验结果表明:该算法能够取得较好的无损压缩性能,同时具有较低的编码复杂度,适合星载超光谱图像的压缩实现。     

基于多尺度自适应胶囊网络的高光谱遥感分类

胶囊网络(CapsNet)是一种新型的神经网络,已被广泛应用于高光谱遥感分类。针对胶囊网络所面临的过拟合和梯度消失等问题,提出一种基于多尺度自适应胶囊网络(MSCaps)的高光谱遥感分类方法。利用多尺度(不同尺寸的输入图像)的卷积层来提取地物的空间特征与光谱特征,并采用一种非迭代自适应路由算法进一步改进CapsNet的结构,避免了耦合系数c_ij的稀疏化引起的过拟合问题。利用PU和SA两个公共高光谱数据集从总体分类精度(OA)和模型训练效率两方面评价了MSCaps的分类性能。在分类精度上,利用MSCaps与支持向量机(SVM)、随机森林(RF)、深度卷积神经网络(CNN)、CapsNet、多尺度的胶囊网络(MCaps)、基于非迭代自适应路由算法的胶囊网络(ARWI-Caps)、多尺度的卷积神经网络(MSCNN)对原始影像的OA进行对比;还与SVM、RF对经主成分分析(PCA)特征提取后的影像的OA进行对比,其中两种分类方法分别简称为PCA-SVM与PCA-RF。在训练效率上,对MSCaps的训练时间和CNN、CapsNet、MSCNN的训练时间进行对比。实验结果表明...     

基于光谱融合的油漆分类方法比较

为了实现对油漆物证的快速、无损以及准确分类,实验收集了犯罪现场常见的5个油漆品牌共计50个油漆样本的红外原始光谱数据和导数光谱数据,结合光谱融合技术,建立了基于KNN、SVM以及逐步判别分析的油漆分类模型.实验结果表明:3种分类模型对于融合光谱的识别率要高于单一光谱;KNN以及SVM分类模型对于其中的3种油漆样本识别率高,但对其余2种样本的分类效果并不好,而逐步判别分析模型对5种油漆样本的各种光谱数据识别率均高于KNN和SVM模型,其中采用逐步判别分析中的Smallest F ratio判别模型对一阶导数光谱和三阶导数光谱融合数据的训练集和测试集实现了完全识别.本文方法的检验效率高,定性能力强,满足公安机关对于相关物证的快速检验要求,为刑事技术人员快速识别油漆物证提供了一种有效的手段.     

基于线性光谱混合模型的地表温度像元分解方法

以北京市Landsat TM为数据源,提出了一种新的地表温度光谱分解模型(Temperature Unmixing with Spectral,TUS),以期将地表温度的空间分辨率提高到30 m.首先,基于线性光谱混合模型获得地表组分的丰度值.然后,基于温度/植被指数选取典型端元的地表温度.最后,综合地表组分的比辐射率数据实现地表温度的分解.结果表明,TUS模型能够有效地提高地表温度的空间分辨率,反映不同地表组分地表温度的空间差异性,平均绝对误差(MAE)和均方根误差(RMSE)分别为1.25 K和2.27 K,非常适合于复杂地表覆盖地区的地表温度降尺度处理.     

高光谱图像分类的全面加权方法研究

像元分类是高光谱数据分析的最基本、最重要内容之一,而基于支持向量机(SVM)的分类方法以其高效性得以广泛使用.原始的SVM分类模型中并没有体现出样本、特征、类别对于分类或分析的不同重要性,从而影响了处理效果.为此,将各样本偏离其类中心的距离映射为样本加权系数;将类内散度矩阵应用于特征加权方法;将SVM方程系统中的单位矩阵对角元素加以调整来完成类别加权.不同加权方法既可以单独使用也可以联合使用.实验表明,所提出的加权方法有助于进一步提高高光谱图像的分类效果.     

基于中红外和远红外数据融合的油茶籽成熟度鉴别

针对油茶籽采收过程中缺乏判断其成熟度的依据,导致茶油的质量和产量不佳等问题,提出一种基于中红外和远红外光谱数据融合检测油茶籽成熟度的方法。采用傅里叶变换红外光谱仪测试了在不同成熟阶段,不同含油率油茶籽的中红外和远红外光谱数据,利用不同特征提取方法（主成分分析法、连续投影算法、无信息变量消除法）对原始光谱数据进行特征提取,再结合支持向量机算法（SVM）建立了油茶籽成熟度的鉴别模型。结果表明：在中红外波段范围内,采用连续投影算法结合遗传算法优化的SVM模型,获得最优的鉴别精度为93.33%;在远红外波段范围内,利用主成分分析法结合遗传算法优化的SVM模型,实现了96.67%的鉴别精度。将中红外波段数据与远红外波段进行数据融合,结合优化后的SVM算法能将鉴别精度提高到100%。该研究表明,红外光谱技术结合优化后的SVM模型可以实现对油茶籽含油率的精确鉴别,数据融合技术能够有效地增加光谱信息并且去除单一光谱的冗余信息。该结果可为油茶的最佳采摘时间提供参考,并可拓展应用到其他农林产品成熟度的鉴别中。     

广东省主要人工林树种光谱分类

为了探索不同树种叶片光谱区分的最佳特征波段以及不同树种光谱分类的 性能,利用地物光谱仪对广东省10个主要人工林树种的叶片光谱数进行了采集。采用遗 传算法(Genetic Algorithm, GA)和连续投影变换算法(Successive Projections Algorithm, SPA) 进行了高光谱数据降维处理,然后结合支持向量机(Support Vector Machine, SVM)和随机森林(Random Forest, RF) 两种方法进行了树种分类。研究发现,通过两种变量选择方式筛选的用于树种分类的光谱范围 主要位于近红外波段。其中,经GA算法筛选的变量建模和预测精度与基于全波段光谱数据的分类精 度较为接近,且比经SPA算法变量筛选的分类结果好。通过比较可知,RF算法所建模型的性能比SVM算 法更稳定,且GA-RF算法在几种分类处理中的性能最好。结果表明,GA-RF算法 可用于基于光谱数据的树种分类研究。     

Resolution Enhancement Technology:Integrated Process Solutions using OPC

DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system.     

Cost-effective test solutions for smart card and other integrated flash applications

From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation.     

An improved parallel thinning algorithm with two subiterations

The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

Today, micro-system technology and the development of new MEMS （Micro-Electro-Mechanical Systems） are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible.     

Study of waveguide coupling efficiency in hybrid silicon lasers

This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel＇s.     

Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers

A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working.     

A rigorous proof of MIMO channel capacity’s increase with antenna number

It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output（MIMO） communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory.     

Call for Papers

正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks