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Landau-Lifshitz-Bio ch equation on Riemannian manifold
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作者 Zonglin JIA Boling GUO 《中国数学前沿:英文版》 SCIE CSCD 2019年第1期45-76,共32页
We bring in Landau-Lifshitz-Bloch equation on m-dimensional closed Riemannian manifold and prove that it admits a unique local solution. When m ≥ 3 and the initial data in L^∞-norm is sufficiently small, the solutio... We bring in Landau-Lifshitz-Bloch equation on m-dimensional closed Riemannian manifold and prove that it admits a unique local solution. When m ≥ 3 and the initial data in L^∞-norm is sufficiently small, the solution can be extended globally. Moreover, for m = 2, we can prove that the unique solution is global without assuming small initial data. 展开更多
关键词 Orientable VECTOR BUNDLE RIEMANNIAN curvature tensor on VECTOR BUNDLE SOBOLEV space on VECTOR BUNDLE
Vector mode based optical direct detection orthogonal frequency division multiplexing transmission in short-reach optical link
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作者 Jianping LI Zhaohui LI 《中国光电子学前沿:英文版》 EI CSCD 2019年第1期41-51,共11页
As one solution to implement the largecapacity space division multiplexing(SDM)transmission systems,the mode division multiplexing(MDM)has gained much attention recently.The vector mode(VM),which is the eigenmode of t... As one solution to implement the largecapacity space division multiplexing(SDM)transmission systems,the mode division multiplexing(MDM)has gained much attention recently.The vector mode(VM),which is the eigenmode of the optical fiber,has also been adopted to realize the optical communications including the transmission over free-space optical(FSO)and optical fiber links.Considering the concerns on the short-reach optical interconnects,the low cost and high integration technologies should be developed.Direct detection(DD)with higher-order modulation formats in combination of MDM technologies could offer an available trade-off in system performance and complexity.We review demonstrations of FSO and fiber high-speed data transmission based on the VM MDM(VMDM)technologies.The special VMs,cylindrical vector beams(CVB),have been generated by the q-plate(QP)and characterized accordingly.And then they were used to implement the VMDM transmission with direct-detection orthogonal frequency division multiplexing(DD-OFDM).These demonstrations show the potential of VMDM-DD-OFDM technology in the large-capacity short-reach transmission links. 展开更多
关键词 space DIVISION MULTIPLEXING (SDM) MODE DIVISION MULTIPLEXING (MDM) few-mode fiber (FMF) VECTOR MODE (VM) cylindrical VECTOR beam (CVB) orthogonal frequency DIVISION MULTIPLEXING (OFDM) direct detection (DD) OPTICAL interconnect
An improved protein expression system for T3SS genes regulation analysis in Xanthomonas oryzae pv.oryzae 预览
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作者 XU Jin-bo ZHANG Cui-ping +5 位作者 WUNIERBIEKE Mei-li YANG Xiao-fei LI Yi-lang CHEN Xiao-bin CHEN Gong-you ZOU Li-fang 《农业科学学报:英文版》 SCIE CAS CSCD 2019年第6期1189-1198,共10页
Xanthomonas oryzea pv.oryzae(Xoo)is the causal agent of bacterial blight of rice,which is a significant threat to many of rice-growing regions.The type Ⅲ secretion system(T3SS)is an essential virulence factor in Xoo.... Xanthomonas oryzea pv.oryzae(Xoo)is the causal agent of bacterial blight of rice,which is a significant threat to many of rice-growing regions.The type Ⅲ secretion system(T3SS)is an essential virulence factor in Xoo.Expression of the T3SS is often induced in the host environment or in hrp-inducing medium but is repressed in nutrient-rich medium.The elucidation of molecular mechanism underlying induction of T3SS genes expression is a very important step to lift the veil on global virulence regulation network in Xoo.Thus,an efficient and reliable genetic tool system is required for detection of the T3SS proteins.In this study,we constructed a protein expression vector pH3-flag based on the backbone of pHM1,a most widely used vector in Xoo strains,especially a model strain PXO99A.This vector contains a synthesized MCS-FLAG cassette that consists of a multiple cloning site(MCS),containing a modified pUC18 polylinker,and Flag as a C-terminal tag.The cassette is flanked by transcriptional terminators to eliminate interference of external transcription enabling detection of accurate protein expression.We evaluated the potential of this expression vector as T3SS proteins detection system and demonstrated it is applicable in the study of T3SS genes expression regulation in Xoo.This improved expression system could be very effectively used as a molecular tool in understanding some virulence genes expression and regulation in Xoo and other Xanthomonas spp. 展开更多
关键词 XANTHOMONAS ORYZAE pv.oryzae broad-host range VECTOR expression VECTOR T3SS GENES
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基于多时间尺度的深层说话人特征提取研究 预览
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作者 王文超 黎塔 《网络新媒体技术》 2019年第5期21-26,共6页
在说话人识别领域中,通过深度神经网络学习深层说话人特征的方法成为了研究热点。然而,针对人类听觉系统是如何处理声音信息的研究,却没有得到说话人识别研究人员足够的重视。这些生物学的研究表明,人类大脑是通过一种利用了多维时间尺... 在说话人识别领域中,通过深度神经网络学习深层说话人特征的方法成为了研究热点。然而,针对人类听觉系统是如何处理声音信息的研究,却没有得到说话人识别研究人员足够的重视。这些生物学的研究表明,人类大脑是通过一种利用了多维时间尺度的处理模式对声音信息进行解析的。基于这些研究,本文提出了一种双通道神经网络模型,其中一条通道处理短时间尺度(即局部)特征,另一条处理长时间尺度(即全局)特征。两种局部特征融合形成可用于说话人识别的声纹特征,称之为t-vector。在RSR2015 Part3文本相关数据集上进行的检测说话人识别系统性能的实验结果表明,不同时间尺度的特征可以互补,并且融合的t-vector特征也优于i-vector和d-vector特征。 展开更多
关键词 说话人识别 深层说话人特征 不同时间尺度 t-vector
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Fault diagnosis of wind turbine bearing based on stochastic subspace identification and multi-kernel support vector machine 预览
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作者 Hongshan ZHAO Yufeng GAO +1 位作者 Huihai LIU Lang LI 《现代电力系统与清洁能源学报(英文)》 CSCD 2019年第2期350-356,共7页
In order to accurately identify a bearing fault on a wind turbine, a novel fault diagnosis method based on stochastic subspace identification(SSI) and multi-kernel support vector machine(MSVM) is proposed. Firstly, th... In order to accurately identify a bearing fault on a wind turbine, a novel fault diagnosis method based on stochastic subspace identification(SSI) and multi-kernel support vector machine(MSVM) is proposed. Firstly, the collected vibration signal of the wind turbine bearing is processed by the SSI method to extract fault feature vectors. Then, the MSVM is constructed based on Gauss kernel support vector machine(SVM) and polynomial kernel SVM. Finally, fault feature vectors which indicate the condition of the wind turbine bearing are inputted to the MSVM for fault pattern recognition. The results indicate that the SSI-MSVM method is effective in fault diagnosis for a wind turbine bearing and can successfully identify fault types of bearing and achieve higher diagnostic accuracy than that of K-means clustering, fuzzy means clustering and traditional SVM. 展开更多
关键词 Wind TURBINE Bearing Fault diagnosis Stochastic SUBSPACE identification(SSI) Multi-kernel support vector machine(MSVM)
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Development of a particle swarm optimization based support vector regression model for titanium dioxide band gap characterization 预览
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作者 Taoreed O.Owolabi 《半导体学报:英文版》 EI CAS CSCD 2019年第2期49-55,共7页
Energy band gap of titanium dioxide(TiO2) semiconductor plays significant roles in many practical applications of the semiconductor and determines its appropriateness in technological and industrial applications such ... Energy band gap of titanium dioxide(TiO2) semiconductor plays significant roles in many practical applications of the semiconductor and determines its appropriateness in technological and industrial applications such as UV absorption, pigment,photo-catalysis, pollution control systems and solar cells among others. Substitution of impurities into crystal lattice structure is the most commonly used method of tuning the band gap of TiO2 for specific application and eventually leads to lattice distortion. This work utilizes the distortion in the lattice structure to estimate the band gap of doped TiO2, for the first time, through hybridization of a particle swarm optimization algorithm(PSO) with a support vector regression(SVR) algorithm for developing a PSO-SVR model. The precision and accuracy of the developed PSO-SVR model was further justified by applying the model for estimating the effect of cobalt-sulfur co-doping, nickel-iodine co-doping, tungsten and indium doping on the band gap of TiO2 and excellent agreement with the experimentally reported values was achieved. Practical implementation of the proposed PSO-SVR model would further widen the applications of the semiconductor and reduce the experimental stress involved in band gap determination of TiO2. 展开更多
关键词 band gap LATTICE DISTORTION crystal LATTICE parameters particle SWARM optimization support vector regression titanium dioxide
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Influence Analysis on the Floating Underwater Monitoring System Applicable for Very-Low-Frequency Acoustic Measurement 预览
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作者 WANG Zhen ZHENG Yi +3 位作者 MAO Yu-feng WANG Ya-zhou YANG Qun HAO Zong-rui 《中国海洋工程:英文版》 SCIE EI CSCD 2019年第3期373-383,共11页
Ocean vector acoustic measurement is feasible affected by the hydrodynamic interference caused by the flow fluctuations and structural vibrations, especially in the very-low-frequency monitoring. Hence, a novel horizo... Ocean vector acoustic measurement is feasible affected by the hydrodynamic interference caused by the flow fluctuations and structural vibrations, especially in the very-low-frequency monitoring. Hence, a novel horizontal floating platform including a horizontal floating cable, vertical mooring cable and floating main body is proposed and described in this paper. It has the advantages of good maneuverability along with the current and multi-stage vibration isolation. The main application of this platform is to measure the ocean ambient noise coming from the wave fluctuation and the deterministic acoustic signals such as aquatic organisms, underwater targets and sailing vehicles. The influence of the current fluctuation on the attitude angle and flow induced vibration of cables and main body are analyzed with some previous sea test data. Moreover, the comparison between the vertical type platform used before and the horizontal type platform is also discussed. It is concluded that there is obvious relevance between the attitude angle and ocean current variation. Meanwhile, the abnormal influence on the main body is caused by the vibration transmission from the fluctuation of cables. There will be the influence on the accuracy of the acoustic measurement above 100 Hz, and the inherent vibration characteristic of the main body is the primary reason. 展开更多
关键词 HYDRODYNAMIC INTERFERENCE vector acoustics very-low-frequency UNDERWATER monitoring platform ATTITUDE angle
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Machine Learning Approach to Enhance the Performance of MNP?Labeled Lateral Flow Immunoassay
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作者 Wenqiang Yan Kan Wang +3 位作者 Hao Xu Xuyang Huo Qinghui Jin Daxiang Cui 《纳微快报:英文版》 CAS CSCD 2019年第1期132-146,共15页
The use of magnetic nanoparticle(MNP)-labeled immunochromatography test strips(ICTSs)is very important for point-ofcare testing(POCT).However,common diagnostic methods cannot accurately analyze the weak magnetic signa... The use of magnetic nanoparticle(MNP)-labeled immunochromatography test strips(ICTSs)is very important for point-ofcare testing(POCT).However,common diagnostic methods cannot accurately analyze the weak magnetic signal from ICTSs,limiting the applications of POCT.In this study,an ultrasensitive multiplex biosensor was designed to overcome the limitations of capturing and normalization of the weak magnetic signal from MNPs on ICTSs.A machine learning model for sandwich assays was constructed and used to classify weakly positive and negative samples,which significantly enhanced the specificity and sensitivity.The potential clinical application was evaluated by detecting 50 human chorionic gonadotropin(HCG)samples and 59 myocardial infarction serum samples.The quantitative range for HCG was 1–1000 mIU mL-1 and the ideal detection limit was 0.014 mIU mL-1,which was well below the clinical threshold.Quantitative detection results of multiplex cardiac markers showed good linear correlations with standard values.The proposed multiplex assay can be readily adapted for identifying other biomolecules and also be used in other applications such as environmental monitoring,food analysis,and national security. 展开更多
关键词 POINT-OF-CARE testing IMMUNOCHROMATOGRAPHY test STRIPS Magnetic nanoparticles MACHINE learning Support vector MACHINE
云南省边境地区景洪市疟疾媒介调查
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作者 杨锐 郑宇婷 +6 位作者 杨晓羽 董利民 林祖锐 周耀武 曾旭灿 李鸿斌 姜进勇 《中国寄生虫学与寄生虫病杂志》 CAS CSCD 北大核心 2019年第4期406-410,416共6页
目的了解云南省边境地区景洪市疟疾重要传播媒介的按蚊种类、生态习性及其疟原虫子抱子感染情况。方法于2015年在景洪市选取1个历史上疟疾流行高发村曼辉龙村为调查点,6-10月每月捕蚊3d。在调査点东、西、南、北、中5个方位各选择1户人... 目的了解云南省边境地区景洪市疟疾重要传播媒介的按蚊种类、生态习性及其疟原虫子抱子感染情况。方法于2015年在景洪市选取1个历史上疟疾流行高发村曼辉龙村为调查点,6-10月每月捕蚊3d。在调査点东、西、南、北、中5个方位各选择1户人房和畜房,采用灯诱法通宵捕捉按蚊,调查按蚊种群密度;多重PCR检测按蚊胃血,观察其嗜血习性。选择村内和村外各1处采用帐诱法捕捉按蚊,观察按蚊夜间活动规律;采用巢式PCR检测按蚊疟原虫子抱子感染情况。结果共捕获1286只按蚊,属13种,其中中华按蚊936只(占72.8%),微小按蚊188只(占14.6%),为当地按蚊优势蚊种。按蚊的捕获来源地主要为畜房,占85.6%(1101只)。125份中华按蚊胃血多重PCR检测结果显示,人血指数为0,猪血指数为100。中华按蚊村内叮人率为0.6只/(人·h),村外的叮人率为0.2只/(人·h),夜间活动高峰期为20:00-22:00。101只微小按蚊、517只中华按蚊和40只多斑按蚊巢式PCR检测,均未发现疟原虫子抱子感染。结论景洪市按蚊媒介种群以中华按蚊为主,其次为微小按蚊。中华按蚊以嗜家畜血为主。捕获的按蚊中未检测到疟原虫子孢子感染。 展开更多
关键词 疟疾 媒介 按蚊 种群 疟原虫子孢子 生态习性 云南省景洪市
Three-Dimensional Growth of Coherent Ferrite in Austenite:A Molecular Dynamics Study
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作者 Zhi-Peng Sun Fu-Zhi Dai +1 位作者 Ben Xu Wen-Zheng Zhang 《金属学报:英文版》 SCIE EI CAS CSCD 2019年第6期669-676,共8页
Coherent second phase often exhibits anisotropic morphology with specifi c orientations with respect to both the second and the matrix phases.As a key feature of microstructure,the morphology of the coherent particles... Coherent second phase often exhibits anisotropic morphology with specifi c orientations with respect to both the second and the matrix phases.As a key feature of microstructure,the morphology of the coherent particles is essential for understanding the second-phase strengthening eff ect in various industrial alloys.This letter reports anisotropic growth of coherent ferrite from austenite matrix in pure iron based on molecular dynamics simulation.We found that the ferrite grain tends to grow into an elongated plate-like shape,independent of its initial confi guration.The fi nal shape of the ferrite is closely related to the misfi t between the two phases,with the longest direction and the broad facet of the plate being,respectively,consistent with the best matching direction and the best matching plane calculated via the Burgers vector content(BVC)method.The strain energy calculation in the framework of Eshelby’s inclusion theory verifi es that the simulated orientation of the coherent ferrite is energetically favorable.It is anticipated that the BVC method will be applicable in analysis of anisotropic growth and morphology of coherent second phase in other phase transformation systems. 展开更多
关键词 COHERENT FERRITE Anisotropic GROWTH Molecular dynamics simulation BURGERS vector content Eshelby’s inclusion theory
骨成形蛋白-2炎性副作用的研究进展
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作者 焦宏伟 李云鹏飞 +1 位作者 李冬梅 高明 《兰州大学学报:医学版》 CAS 2019年第1期85-90,共6页
骨成形蛋白-2 (BMP-2)被认为是活性最强的,唯一能单独诱导成骨的因子。2002年BMP-2被美国食品和药物管理局批准为具有体内诱导新骨形成能力的生物活性蛋白,并广泛应用于临床。随着BMP-2临床应用的增加,其相关副作用日益明显,包括术后炎... 骨成形蛋白-2 (BMP-2)被认为是活性最强的,唯一能单独诱导成骨的因子。2002年BMP-2被美国食品和药物管理局批准为具有体内诱导新骨形成能力的生物活性蛋白,并广泛应用于临床。随着BMP-2临床应用的增加,其相关副作用日益明显,包括术后炎症反应及相关副作用、异位骨形成、破骨细胞介导的骨吸收和脂肪组织形成。炎症副作用最常见,危及生命的颈椎肿胀与其密切相关。本研究就BMP-2的生物活性进行概述,重点介绍BMP-2炎症副作用的发生原因、分子机制以及减少BMP-2炎症并发症的方法。 展开更多
关键词 骨成形蛋白-2 炎性反应 信号转导 载体
经上皮准分子激光角膜切削术的散光矫正效果
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作者 吕欢 《中华眼外伤职业眼病杂志》 2019年第1期59-62,共4页
目的评价经上皮准分子激光角膜切削术(transPRK)的散光矫正效果。方法回顾性分析2017年5月至2018年2月接受transPRK术后3个月随访数据完整的的近视散光32例(64眼)的临床资料。分为低度散光组(-0.25D~-0.75D)共43眼和中高散光组(1.00D~-2... 目的评价经上皮准分子激光角膜切削术(transPRK)的散光矫正效果。方法回顾性分析2017年5月至2018年2月接受transPRK术后3个月随访数据完整的的近视散光32例(64眼)的临床资料。分为低度散光组(-0.25D~-0.75D)共43眼和中高散光组(1.00D~-2.75D)共21眼。收集术前及术后3个月屈光值参数。使用标准矢量分析法对两组人群术后散光相关矢量参数进行比较。结果术后两组间角度误差(t=2.547,P=0.014)、矫正率(t=2.117,P=0.039)、误差率(t=3.679,P=0.001)差异有统计学意义。全部受试者总体误差率与预期屈光矫正量呈正相关(r=0.339,P<0.01),而矫正率与预期屈光矫正量间相关性无统计学意义。结论TransPRK术后散光矫正的结果与患者术前散光度数密切相关。临床工作中应调整散光矫正目标值并排除其他影响散光矫正的相关因素。 展开更多
关键词 分析 矢量 角膜切削术 准分子激光 经上皮 散光 近视
Characteristics and advantages of adenoassociated virus vector-mediated gene therapy for neurodegenerative diseases 预览
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作者 Yuan Qu Yi Liu +2 位作者 Ahmed Fayyaz Noor Johnathan Tran Rui Li 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第6期931-938,共8页
Common neurodegenerative diseases of the central nervous system are characterized by progressive damage to the function of neurons,even leading to the permanent loss of function.Gene therapy via gene replacement or ge... Common neurodegenerative diseases of the central nervous system are characterized by progressive damage to the function of neurons,even leading to the permanent loss of function.Gene therapy via gene replacement or gene correction provides the potential for transformative therapies to delay or possibly stop further progression of the neurodegenerative disease in affected patients.Adeno-associated virus has been the vector of choice in recent clinical trials of therapies for neurodegenerative diseases due to its safety and efficiency in mediating gene transfer to the central nervous system.This review aims to discuss and summarize the progress and clinical applications of adeno-associated virus in neurodegenerative disease in central nervous system.Results from some clinical trials and successful cases of central neurodegenerative diseases deserve further study and exploration. 展开更多
关键词 nerve REGENERATION central nervous system gene therapy NEURODEGENERATIVE DISEASE viral vector ADENO-ASSOCIATED virus Alzheimer’s DISEASE Parkinson’s DISEASE Huntington’s DISEASE amyotrophic lateral SCLEROSIS spinal muscular atrophy neural REGENERATION
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一种基于球面QTM格网的面要素边界跟踪填充算法 预览
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作者 王谦 赵学胜 李亚路 《地理与地理信息科学》 CSCD 北大核心 2019年第3期16-20,共5页
为实现四元三角网(Quaternary Triangular Mesh,QTM)对球面面状要素矢量数据的离散化及可视化,该文将基于栅格单元的"边界代数法"扩展到球面三角格网单元,提出了一种基于QTM格网的边界跟踪填充算法,主要内容包括:通过ETP投影... 为实现四元三角网(Quaternary Triangular Mesh,QTM)对球面面状要素矢量数据的离散化及可视化,该文将基于栅格单元的"边界代数法"扩展到球面三角格网单元,提出了一种基于QTM格网的边界跟踪填充算法,主要内容包括:通过ETP投影实现球面QTM格网与平面三角格网的相互转换,建立矢量线角度与三角格元邻近搜索的对应关系;"边界跟踪"并记录边界格元进行分类处理;最终给出"边界跟踪"下两种不同的填充模式。实验表明,该算法实现了球面矢量多边形在QTM格网中的填充。 展开更多
关键词 四元三角网 矢量 多边形填充 边界跟踪
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Photonic Vector Signal Generation by Frequency Sextupling for Radio Over Fiber Systems 预览
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作者 Siyang Wang Nai’an Liu 《哈尔滨工业大学学报:英文版》 EI CAS 2019年第4期18-24,共7页
To generate high-frequency radio frequency(RF) vector signals, a vector signal generation method by optical frequency sextupling using a dual-parallel modulator is proposed. The method modulates vector signal on +3 rd... To generate high-frequency radio frequency(RF) vector signals, a vector signal generation method by optical frequency sextupling using a dual-parallel modulator is proposed. The method modulates vector signal on +3 rd order optical sideband and local oscillator(LO) signal on-3 rd order sideband using the intermodulation process in the DPMZM. After suppressing of the optical carrier and other sidebands through proper adjustment for modulator biases and modulation index, a frequency sextupled millimeter-wave vector signal can be generated after photodetection. The frequency sextupling will lower the bandwidth of the modulator, the local oscillator and the driving circuits. In addition, the phase of generated signal is not distorted after detection, and the power fading after fiber transmission can be avoided. In the simulation, a 500-MSym/s QPSK signal at 60 GHz is generated by 10-GHz drive signal. After travelling over fiber with length of 20/30/40-km, receiver power penalty keeps below 2.5 dB. 展开更多
关键词 dual-parallel MACH-ZEHNDER modulator(DPMZM) FREQUENCY MULTIPLICATION FREQUENCY UP-CONVERSION VECTOR signal radio over fiber(RoF)
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Assessing supply chain performance using genetic algorithm and support vector machine
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作者 ZHAO Yu 《生态经济:英文版》 2019年第2期101-108,共8页
The rough set-genetic support vector machine(SVM) model is applied to supply chain performance evaluation. First, the rough set theory is used to remove the redundant factors that affect the performance evaluation of ... The rough set-genetic support vector machine(SVM) model is applied to supply chain performance evaluation. First, the rough set theory is used to remove the redundant factors that affect the performance evaluation of supply chain to obtain the core influencing factors. Then the support vector machine is used to extract the core influencing factors to predict the level of supply chain performance. In the process of SVM classification, the genetic algorithm is used to optimize the parameters of the SVM algorithm to obtain the best parameter model, and then the supply chain performance evaluation level is predicted. Finally, an example is used to predict this model, and compared with the result of using only rough set-support vector machine to predict. The results show that the method of rough set-genetic support vector machine can predict the level of supply chain performance more accurately and the prediction result is more realistic, which is a scientific and feasible method. 展开更多
关键词 supply CHAIN performance evaluation ROUGH set theory support VECTOR machine GENETIC algorithm
Errors in Current Velocity in the Low-latitude North Pacific:Results from the Regional Ocean Modeling System 预览
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作者 Xixi WEN Wansuo DUAN 《大气科学进展:英文版》 SCIE CAS CSCD 2019年第4期397-416,共20页
Using the Regional Ocean Modeling System,this study investigates the simulation uncertainties in the current velocity in the low-latitude North Pacific where the Kuroshio originates [i.e.,the beginning of the Kuroshio... Using the Regional Ocean Modeling System,this study investigates the simulation uncertainties in the current velocity in the low-latitude North Pacific where the Kuroshio originates [i.e.,the beginning of the Kuroshio(BK)].The results show that the simulation uncertainties largely reflect the contributions of wind stress forcing errors,especially zonal wind stress errors,rather than initial or boundary errors.Using the idea of a nonlinear forcing singular vector,two types of zonal wind stress errors(but sharing one EOF mode)are identified from error samples derived from reanalysis data as having the potential to yield large simulation uncertainties.The type-1 error possesses a pattern with positive anomalies covering the two zonal bands of 0°–15°N and 25°–40°N in the Pacific Ocean,with negative anomalies appearing between these two bands;while the type-2 error is almost opposite to the type-1 error.The simulation uncertainties induced by the type-1 and-2 errors consist of both large-scale circulation errors controlled by a mechanism similar to the Sverdrup relation and mesoscale eddy-like errors generated by baroclinic instability.The type-1 and-2 errors suggest two areas: one is located between the western boundary and the meridional 130°E along 15°–20°N,and the other is located between 140°–150°E and along 15°–20°N.The reduction of errors over these two areas can greatly improve the simulation accuracy of the current velocity at BK.These two areas represent sensitive areas for targeted observations associated with the simulation of the current velocity at BK. 展开更多
关键词 KUROSHIO nonlinear FORCING SINGULAR vector TARGETED observation
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Plasmonic tip internally excited via an azimuthal vector beam for surface enhanced Raman spectroscopy
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作者 Min Liu Wending Zhang +8 位作者 Fan fan Lu Tianyang Xue Xin Li Lu Zhang Dong Mao Ligang Huang Feng Gao Ting Mei Jianlin Zhao 《光子学研究:英文版》 CSCD 2019年第5期526-531,共6页
The synergy of a plasmonic tip and fiber-based structure light field excitation can provide a powerful tool for Raman examination. Here, we present a method of Raman spectrum enhancement with an Ag-nanoparticles(Ag-NP... The synergy of a plasmonic tip and fiber-based structure light field excitation can provide a powerful tool for Raman examination. Here, we present a method of Raman spectrum enhancement with an Ag-nanoparticles(Ag-NPs)-coated fiber probe internally excited via an azimuthal vector beam(AVB), which is directly generated in a few-mode fiber by using an acoustically induced fiber grating. Theoretical analysis shows that gap mode can be effectively generated on the surface of the Ag-NPs-coated fiber probe excited via an AVB. The experimental result shows that the intensity of Raman signal obtained with analyte molecules of malachite green by exciting the Ag-NPs-coated fiber probe via an AVB is approximately eight times as strong as that via the linear polarization beam(LPB), and the activity of the AVB-excited fiber probe can reach 10^-11 mol∕L, which cannot be achieved by LPB excitation.Moreover, the time stability and reliability are also examined, respectively. 展开更多
关键词 Raman spectroscopy azimuthal VECTOR beam(AVB) Ag-nanoparticles(Ag-NPs) linear polarization beam(LPB)
Obstacle Avoidance Method for a Redundant Manipulator Based on a Configuration Plane 预览
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作者 Yanhui Wei Yanfeng Zhao +4 位作者 Jing Liu Shenggong Hao Lixue Xu Qiang Zhu Anqi Wang 《北京理工大学学报:英文版》 EI CAS 2019年第3期456-468,共13页
This paper presents a novel approach of obstacle avoidance for redundant manipulators, which is challenging with the considerations of the building of universal kinematics, the formation of dynamics, and the generatio... This paper presents a novel approach of obstacle avoidance for redundant manipulators, which is challenging with the considerations of the building of universal kinematics, the formation of dynamics, and the generation of trajectories. A universal approach to deal with obstacle avoidance for the redundant manipulator, that is based on the configuration plane, is presented. The paper also examines common serial robot configurations and introduces a method for classification, partitioning, simplification, and forms of expression used in the workspace to define the configuration plane. This relatively new method is combined with a weighted space vector method to match the configuration plane and solve the inverse kinematics problem. The proposed planner is demonstrated with examples, in which the proposed planner is shown to be capable of providing a smoother trajectory. 展开更多
关键词 REDUNDANT manipulator CONFIGURATION PLANE trajectory generation OBSTACLE AVOIDANCE space vector
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TrkA regulates the regenerative capacity of bone marrow stromal stem cells in nerve grafts 预览
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作者 Mei-Ge Zheng Wen-Yuan Sui +8 位作者 Zhen-Dan He Yan Liu Yu-Lin Huang Shu-Hua Mu Xin-Zhong Xu Ji-Sen Zhang Jun-Le Qu Jian Zhang Dong Wang 《中国神经再生研究:英文版》 SCIE CAS CSCD 2019年第10期1765-1771,共7页
We previously demonstrated that overexpression of tropomyosin receptor kinase A(TrkA)promotes the survival and Schwann celllike differentiation of bone marrow stromal stem cells in nerve grafts,thereby enhancing the r... We previously demonstrated that overexpression of tropomyosin receptor kinase A(TrkA)promotes the survival and Schwann celllike differentiation of bone marrow stromal stem cells in nerve grafts,thereby enhancing the regeneration and functional recovery of the peripheral nerve.In the present study,we investigated the molecular mechanisms underlying the neuroprotective effects of TrkA in bone marrow stromal stem cells seeded into nerve grafts.Bone marrow stromal stem cells from Sprague-Dawley rats were infected with recombinant lentivirus vector expressing rat TrkA,TrkA-shRNA or the respective control.The cells were then seeded into allogeneic rat acellular nerve allografts for bridging a 1-cm right sciatic nerve defect.Then,8 weeks after surgery,hematoxylin and eosin staining showed that compared with the control groups,the cells and fibers in the TrkA overexpressing group were more densely and uniformly arranged,whereas they were relatively sparse and arranged in a disordered manner in the TrkA-shRNA group.Western blot assay showed that compared with the control groups,the TrkA overexpressing group had higher expression of the myelin marker,myelin basic protein and the axonal marker neurofilament 200.The TrkA overexpressing group also had higher levels of various signaling molecules,including TrkA,pTrkA(Tyr490),extracellular signal-regulated kinases 1/2(Erkl/2),pErk1/2(Thr202/Tyr204),and the anti-apoptotic proteins Bcl-2 and Bcl-xL.In contrast,these proteins were downregulated,while the pro-apoptotic factors Bax and Bad were upregulated,in the TrkA-shRNA group.The levels of the TrkA effectors Akt and pAkt(Ser473)were not different among the groups.These results suggest that TrkA enhances the survival and regenerative capacity of bone marrow stromal stem cells through upregulation of the Erk/Bcl-2 pathway.All procedures were approved by the Animal Ethical and Welfare Committee of Shenzhen University,China in December 2014(approval No.AEWC-2014-001219). 展开更多
关键词 NERVE REGENERATION bone marrow stromal stem cells TROPOMYOSIN RECEPTOR kinase A RECEPTOR LENTIVIRAL vector shRNA extracellular SIGNAL-REGULATED protein kinases 1/2 Bcl-2 NERVE grafts peripheral NERVE REGENERATION survival neural REGENERATION
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