A Fingerprint Minutiae Matching Method Based on Line Segment Vector

Minutiae-based fingerprint matching is the most commonly used in an automatic fingerprint identification system. In this paper, we propose a minutia matching method based on line segment vector. This method uses all the detected minutiae （the ridge ending and the ridge bifurcation） in a fingerprint image to create a set of new vectors （line segment vector）. Using these vectors, we can determine a truer reference point more efficiently. In addition, this new minutiae vector can also increase the accuracy of the minutiae matching. By experiment on the public domain collections of fingerprint images fvc2004 DID set A and DB4 set A, the result shows that our algorithm can obtain an improved verification performance.

On-line Estimation of Biomass in Fermentation Process Using Support Vector Machine

Biomass is a key factor in fermentation process, directly influencing the performance of the fermenta- tion system as well as the quality and yield of the targeted product. Therefore, the on-line estimation of biomass is indispensable. The soft-sensor based on support vector machine (SVM) for an on-line biomass estimation was ana- lyzed in detail, and the improved SVM called the weighted least squares support vector machine was presented to follow the dynamic feature of fermentation process. The model based on the modified SVM was developed and demonstrated using simulation experiments.

Application of the sun line-of-sight vector in the optimal attitude estimation of deep-space probe

This paper proposed an optimal algorithm using the sun line-of-sight vector to improve the probe attitude estimation accuracy in deep-space mission.Firstly,the elaborate analysis of the attitude estimation error from vector observations was done to demonstrate that the geometric relation between the reference vectors is an important factor which influences the accuracy of attitude estimation.Then,with introduction of the sun line-of-sight vector,the attitude quaternion obtained from the star-sensor was converted into a pair of mutually perpendicular reference vectors perpendicular to the sun vector.The normalized weights were calculated according to the accuracy of the sensors.Furthermore,the optimal attitude estimation in the least squares sense was achieved with the quaternion estimation method.Finally,the results of simulation demonstrated the validity of the proposed optimal algorithm based on the practical data of the Deep Impact mission.

On-line Chatter Detection Using an Improved Support Vector Machine

On-line chatter detection can avoid unstable cutting through monitoring the machining process.In order to identify chatter in a timely manner,an improved Support Vector Machine(SVM)is developed in this paper,based on extracted features.In the SVM model,the penalty factor(e)and the core parameter(g)have important influence on the classification,more than from Kernel Functions(KFs).Hence,first the classification results are conducted using different KFs.Then two methods are presented for exploring the best parameters.The chatter identification results show that the Genetic Algorithm(GA)approach is more suitable for deciding the parameters than the Grid Explore(GE)approach.

Magnetic Field Curves and Magnetic Equipotential Surfaces around Crossing Electrical Wires Replacing Classical Magnetic Field Lines

This article is based on a recent model specifically defining magnetic field values around electrical wires. With this model, calculations of field around parallel wires were obtained. Now, this model is extended with the new concept of magnetic equipotential surface to magnetic field curves around crossing wires. Cases of single, double, and triple wires are described. Subsequent article will be conducted for more general scenarios where wires are neither infinite nor parallel.

Construction of a replication-competent hepatitis B virus vector carrying secreted luciferase transgene and establishment of new hepatitis B virus replication and expression cell lines

BACKGROUND Previously,we have successfully constructed replication-competent hepatitis B virus(HBV)vectors by uncoupling the P open reading frame(ORF)from the preC/C ORF to carefully design the transgene insertion site to overcome the compact organization of the HBV genome and maintain HBV replication competence.Consequently,the replication-competent HBV vectors carrying foreign genes,including pCH-BsdR,carrying blasticidin resistance gene(399 bp),and pCH-hrGFP,carrying humanized renilla green fluorescent protein gene(720 bp),were successfully obtained.However,the replication efficiency of the former is higher but it is tedious to use,while that of the latter is poor and cannot be quantified.Hence,we need to search for a new reporter gene that is convenient and quantifiable for further research.AIM To establish a helpful tool for intracellular HBV replication and anti-viral drugs screening studies.METHODS We utilized the replication-competent HBV viral vectors constructed by our laboratory,combined with the secreted luciferase reporter gene,to construct replication-competent HBV vectors expressing the reporter gene secretory Nanoluc Luciferase(SecNluc).HepG2.TA2-7 cells were transfected with this vector to obtain cell lines with stably secreted HBV particles carrying secNluc reporter gene.RESULTS The replication-competent HBV vector carrying the SecNluc reporter gene pCHsNLuc could produce all major viral RNAs and a full set of envelope proteins and achieve high-level secreted luciferase expression.HBV replication intermediates could be produced from this vector.Via transfection with pTRE-sNLuc and selection by hygromycin,we obtained isolated cell clones,named HBV-NLuc-35 cells,which could secrete secNLuc recombinant viruses,and were sensitive to existing anti-HBV drugs.Using differentiated HepaRG cells,it was verified that recombinant HBV possessed infectivity.CONCLUSION Our research demonstrated that a replication-competent HBV vector carrying a secreted luciferase transgene possesses replication and expression ability,and the established HBV replication and expression cell lines could stably secrete viral particles carrying secNluc reporter gene.More importantly,the cell line and the secreted recombinant viral particles could be used to trace HBV replication or infection.

基于VMD-FOA-LSSVM的输电线路故障诊断方法

针对现有输电线路短路故障诊断方法精度较低的问题,提出了一种基于VMD-FOA-LSSVM的输电线路故障诊断方法。首先通过VMD对发生故障后的三相电压数据进行分解,得到了一连串的模态成分;随后分别求出各模态分量的样本熵值,并将这些样本熵值组成故障特征集。随后通过改变步长加强了果蝇算法的全局搜索能力,采用改良的果蝇算法优化最小二乘支持向量机的分类模型,进一步提高该模型的分类性能。最后将故障特征集输入到FOA-LSSVM模型里进一步训练,并与几种常用的故障诊断方法进行对比。实验结果表明,FOA-LSSVM方法在输电线路故障诊断方面精度较高,可以更准确、更快速地对输电线路的故障进行诊断。

Establishment of a Functional Cell Line Expressing both Subunits of H1a and H2c of Human Hepatocyte Surface Molecule ASGPR

To better understand the effect of a new split variant of human asialoglycoprotein receptor (ASGPR H1b) on ASGPR ligands’ binding ability, we established a functional cell line which expresses ASGPR.The full lengths of ASGPRH1a and H2c fragments from human liver were amplified by reverse transcript PCR (RT-PCR) and inserted into eukaryotic expression vector pIRES2EFP, pCDNA3.1 (Zeo+) respectively.The recombinants were cotransfected into HeLa cells.After selection by using Neocin and Zeocin, a stably transfected cell line was established, which was designated 4-1-6.The transcription and expression of ASGPRH1a and H2c in 4-1-6 were confirmed by RT-PCR, Western blotting and immunofluorescence.The endocytosis function of the artificial "ASGPR" on the surface of 4-1-6 was tested by FACS.It was found that the cell line 4-1-6 could bind ASGPR natural ligand molecular asialo-orosomucoid (ASOR).After the eukaryotic plasmid H1b/pCDNA3.1 (neo) was transfected into cell line 4-1-6, H1b did not down-regulate the ligand binding ability of ASGPR.The eukaryotic expression plasmid H1b/pcDNA3.1 (neo) and H2c/pcDNA3.1 (neo) were co-transfected transiently into Hela cell.Neither single H1b nor H1b and H2c could bind ASOR.In conclusion, a functional cell line of human asialoglycoprotein receptor (ASGPR) which expresses both H1a and H2c stably was established.The new split variant H1b has no effect on ASGPR binding to ASOR.ASGPRH1b alone can’t bind to ASOR, it yet can’t form functional complex with ASGPRH2c.

DIRECTIONAL DERIVATIVE OF VECTOR FIELD AND REGULAR CURVES ON TIME SCALES

The general idea in this paper is to study curves of the parametric equations where the parameter varies in a so-called time scale, which may be an arbitrary closed subset of the set of all real numbers. We introduce the directional derivative according to the vector fields.

Evolution of emergent C-points,L-lines,and C-lines in free space

Polarization singularities,which emerge from the incoherent superposition of two vector electric fields with the same frequency,and their evolution in free space are studied analytically and illustrated by numerical examples.It is shown that there exist C-points,L-lines,in particular,C-lines in incoherently superimposed two-dimensional wavefields.Usually,the C-lines are unstable and disappear during the free-space propagation.The motion,pair creation-annihilation process of the emergent C-points,as well as the distortion of the L-lines may take place,and the degree of polarization of the emergent C-points varies upon propagation and may be less than 1.

Vector Magnetic Field Measurement of NOAA AR 10197

A set of two-dimensional Stokes spectral data of NOAA AR 10197 obtained by the Solar Stokes Spectral Telescope （S^3T） at the Yunnan Observatory are quafitatively analyzed. The three components of the vector magnetic field, the strength H, inclination 7 and azimuth X, are derived. Based on the three components, we contour the distributions of the longitudinal magnetic field and transverse magnetic field. The active region （AR） has two different magnetic polarities apparent in the longitudinal magnetic map due to projection effect. There is a basic agreement on the longitudinal magnetic fields between the S^3T and SOHO/MDI magnetograms, with a correlation coefficient PBl = 0.911. The transverse magnetic field of the AR has a radial distribution from a center located in the southwest of the AR. It is also found that the transverse magnetic fields obtained by Huairou Solar Observing Station （HRSOS） have a similar radial distribution. The distributions of transverse magnetic field obtained by S^3T and HRSOS have correlation coefficients, PAzimu = 0.86 and PBt =0.883, in regard to the azimuthal angle and intensity.

Correction of Observation Interference on Z component of Geomagnetic Field From DC Power Lines

为减小直流输电线路对地磁场观测的干扰,采用数学计算的方法精确求解了线路对地磁Z分量的干扰水平。以观测点为原点建立了地磁仪器观测点坐标系,推导了观测点坐标系各坐标轴在地心坐标系中的单位矢量表达式。根据空间矢量点积的定义,得到了空间电流磁场矢量投影到地磁Z分量方向的求解公式。利用推导的公式和直流线路电流磁场三维计算模型,最终求得直流线路对地磁Z分量观测的干扰水平。由此,开发了＂直流线路对地磁观测干扰校正系统＂,并开展了地磁台站和野外联合地磁观测干扰实验。结果表明,直流线路和地磁观测台站距离不超过10km时,提出的数学模型和计算方法误差不超过5%。

基于GS-SVR的架空输电线路工程投资估算预测研究

传统的投资估算编制模式存在过度依赖定额的现象,随着大量工程造价数据的积累,利用其实现投资估算,以弥补传统定额计价模式的不足,能够对建设项目工程造价起到总体控制作用。文章以架空输电线路工程为例,基于支持向量回归机(Support Vector Regression,SVR)研究架空输电线路工程投资估算问题。结果表明:通过选取影响架空输电线路工程投资估算的主要指标,构建基于SVR的架空输电线路工程投资估算模型,并利用改进的网格搜索法(Grid Search,GS)优化模型参数,得到基于GS-SVR的投资估算预测模型;与传统的线性回归和SVR模型相比,GS-SVR模型表现出更为良好的性能。

基于单矢量水听器的水中目标高分辨线谱增强方法

微弱信号检测一直是被动声呐系统远程探测面临的技术挑战。为了解决水下微弱信号条件下,即低信噪比(SNR)情况下,目标线谱检测难点问题,本文基于单矢量水听器信号接收,提出一种水下目标声压振速频域解卷积联合(CPVD)处理方法,可以实现线谱增强以及提高频域分辨率。采用单矢量水听器接收,保证声呐系统体积小,同时利用其具有指向性这一特点,可以抑制噪声,提高信号增益。在此基础上,通过CPVD算法对水中微弱信号进行线谱增强,实现有效检测。本文提出的方法克服了一些增强算法以及功率谱分析算法需要一定的先验知识以及频域线谱分辨率较低的缺点,从仿真分析和海试数据处理结果可以看出:本文所提出的基于单矢量水听器的水下目标线谱增强算法在低SNR条件下提高频率分辨率方面具有优势,为被动声呐系统微弱信号下的线谱检测提供有效算法。

基于固有模态特征向量的混合多端直流输电线路单端量保护方案

混合多端直流输电系统送、受端边界不对称,T区边界不明显,现有直流线路保护难以直接适用,且存在耐过渡电阻能力不足、未考虑T区故障的识别等问题。为此,提出一种基于固有模态特征向量的混合多端直流输电线路单端量保护方案。首先分析线路边界及T区的频率特性,并结合变分模态分解算法对故障信号进行自适应分解,据此筛选出有利于放大区内外故障特征差异的固有模态。接着利用筛选后的模态幅值构造保护特征矩阵以充分利用故障信息,并进一步通过从矩阵到向量的降维方法减少计算量。针对筛选过程引起的特征向量维数不统一问题,建立基于模态中心频率的向量元素合并准则以重构向量使其具有统一维数。最后利用区内外故障对应的特征向量幅值具有明显差异的特点,提出了以向量距离为度量的单端量保护判据。通过仿真表明,所提保护在不同故障条件下均能准确识别,可靠性高,且具有较强的耐过渡电阻能力(500?)和抗噪声能力(20 dB)。

基于三维激光扫描技术的智能制造生产线目标检测研究

智能制造生产线目标图像数据采集过程受到噪声、光照变化等问题,导致输入图像的质量不佳,进而影响目标检测的准确性,对此,设计一种基于三维激光扫描技术的智能制造生产线目标检测方法。首先,采用三维激光扫描仪获取待检测目标点云数据,通过点云变换准则计算数据之间的拓扑关联,生成完整三维激光图像。然后,利用杂交小波变换对三维激光目标图像进行去噪处理。最后,使用能量、熵、对比度、相关性4种参数提取图像纹理特征并采取归一化处理,创建最优分类函数,并运用支持向量机算法划分生产线目标样本图像数据,完成智能制造生产线目标检测工作。实验结果表明,所提方法的交并比值最高时达到0.97,F1值最高时达到0.96,平均检测耗时仅为0.53 s,说明所提方法的检测精度高、效率快,鲁棒性强,在实际操作中具备相当的可用性,为智能制造产业提供技术支持。

基于声压振速联合处理的稀疏协方差DOA估计

为充分利用矢量水听器中声压振速信息之间的关系来提高DOA估计精度,本文提出了基于声压振速联合处理的稀疏协方差DOA(Direction ofArrival)估计方法。该方法首先利用声压振速之间的相关性,构造阵列协方差矩阵;其次,将空间入射角度集合进行等角度划分,构造超完备冗余字典;然后,在过完备基上寻找阵列协方差矩阵的最稀疏系数,利用系数向量中的非零行所对应的行号得到DOA估计值。将该算法与CBF算法及L1-SVD算法进行对比仿真实验,结果表明,在信号源数分别为3,4,5的情形下,本文所提算法在低信噪比和小快拍数情形时,具有更低的均方根误差,DOA估计性能优势明显。

表达猪流行性腹泻病毒N蛋白Vero细胞系的构建及初步鉴定

【目的】构建表达猪流行性腹泻病毒(PEDV)N蛋白的Vero细胞系,将有助于PEDV的进一步深入研究。【方法】本研究将N基因克隆到慢病毒载体中,构建重组质粒pLenti-CMV-N,利用慢病毒载体包装系统转染293T细胞,包装表达N蛋白的慢病毒颗粒,将慢病毒颗粒转导至Vero细胞,用潮霉素B初步筛选阳性细胞,采用终点稀释法,筛选表达PEDV N蛋白的Vero细胞系,最后进行鉴定。【结果】RT-PCR结果表明构建的细胞系基因组中存在N基因序列,Western blot和IFA试验验证了N蛋白在细胞系中的表达。【结论】本研究成功构建了表达PEDV N蛋白的Vero细胞系。

激光点云特征与知识规则协同的车道线提取

实现车道线高效的检测提取是自动驾驶领域中亟待攻克的关键技术之一,众多基于视觉方案的检测算法由于图像数据的特点存在一定局限性,如天气光照影响成像质量、难以兼顾弯道直道等。本文结合三维激光点云优势与道路知识规则提出了一种车道线自动提取算法。首先,通过多次强化道路边界高程差异获取路面点;其次,简化Isodata算法,自适应地得到反射强度滤波阈值;然后采用随机一致性算法检测直线聚类得到候选车道,将候选车道映射成二维矢量并通过类间距约束提取正确车道线;最后,基于相邻关键特征点对的向量拓扑关系一致性实现车道线拓扑重构,得到对应现实世界中意义完整的车道线。算法在车道线达5~6条的情况下,召回率达92.46%,准确率达94.79%,综合评价指标达92.41%,实验结果证明了方法的有效性和可行性。

Transfection of the glial cell line-derived neurotrophic factor gene promotes neuronal differentiation

Glial cell line-derived neurotrophic factor recombinant adenovirus vector-transfected bone marrow mesenchymal stem cells were induced to differentiate into neuron-like cells using inductive medium containing retinoic acid and epidermal growth factor. Cell viability, micro- tubule-associated protein 2-positive cell ratio, and the expression levels of glial cell line-derived neurotrophic factor, nerve growth factor and growth-associated protein-43 protein in the su- pernatant were significantly higher in glial cell line-derived neurotrophic factor/bone marrow mesenchymal stem cells compared with empty virus plasmid-transfected bone marrow mes- enchymal stem cells. Furthermore, microtubule-associated protein 2, glial cell line-derived neurotrophic factor, nerve growth factor and growth-associated protein743 mRNA levels in cell pellets were statistically higher in glial cell line-derived neurotrophic factor/bone marrow mesen- chymal stem cells compared with empty virus plasmid-transfected bone marrow mesenchymal stem cells. These results suggest that glial cell line-derived neurotrophic factor/bone marrow mesenchymal stem cells have a higher rate of induction into neuron-like cells, and this enhanced differentiation into neuron-like cells may be associated with up-regulated expression of glial cell line-derived neurotrophic factor, nerve growth factor and growth-associated protein-43.