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    题名 作者 年代 出处 被引量
1虚拟经济与实体经济关系模型——对我国当前股市与实体经济关系的一种解释显示文摘近几年来中国股票市场与实体经济出现了明显的背离 ,本文试图从虚拟经济的角度解释这一现象。在对有关股票市场与实体经济背离的研究成果进行总结回顾的基础上 ,构建货币、虚拟经济与实体经济间关系的模型。分析发现 ,虚拟资产收益率和实物资产收益率的差异是股实背离的主要原因 ,而收益率差异又根源于股市结构和实体经济结构的非对称性 ,这种非对称性背后的根本原因在于资本市场体制改革的滞后。刘骏民 伍超明 2004经济研究2004,39,4:179
2Transmission Dynamics of an Outbreak of the COVID-19 Delta Variant B.1.617.2——Guangdong Province,China,May-June 2021显示文摘On May 21,2021,a local case of coronavirus disease 2019(COVID-19)was confirmed in a 75-year-old woman(experienced onset of symptoms on May 18)in Liwan District,Guangzhou City,Guangdong Province,China.The number of infections has increased in the following 10 days and led to 5 generations of transmission.Meng Zhang Jianpeng Xiao Aiping Deng Yingtao Zhang Yali Zhuang Ting Hu Jiansen Li Hongwei Tu Bosheng Li Yan Zhou Jun Yuan Lei Luo Zimian Liang Youzhi Huang Guoqiang Ye Mingwei Cai Gongli Li Bo Yang Bin Xu Ximing Huang Yazun Cui Dongsheng Ren Yanping Zhang Min Kang Yan Li 2021China CDC weekly2021,3,27:51
3分数导数与数字微分器设计显示文摘从信号处理角度来考察分数阶导数和微分问题 .首先论述分数阶微积分的基本概念 ,评论分数阶导数的几种典型定义 ,并重点探讨分数阶导数的频域定义及其基本性质 .紧接着详细研究分数阶微分的实现 :理想分数阶数字微分滤波器和FIR分数阶数字微分滤波的基本性质和设计问题 ,并提出分数阶微分滤波器设计中遇到的新问题以及奇对称微分滤波器、偶对称微分滤波器等新概念 .最后给出一些值得进一步探讨的有趣问题 .袁晓 张红雨 虞厥邦 2004电子学报2004,32,10:46
4基于MATLAB的FIR数字滤波器的方法设计显示文摘数字滤波器是一种具有选择并区分不同频率功能的电路,是在时域内过滤离散信号的数字系统。采用的是窗函数法。研究的重点目的是依据FIR滤波器的特性,分析了FIR滤波器的窗函数设计方法的介绍和选择使用,并利用MATLAB信号处理工具箱来实现验证FIRDF程序的设计。给出了详细的设计理论和具体步骤,并将设计的滤波器应用到一个混和正弦波信号,以验证滤波器的性能,实验证明该滤波器达到了预期的滤波功能。赵颖 刘祖深 李胜寅 2012国外电子测量技术2012,31,10:42
5配永磁机构的真空断路器同步分合闸控制系统设计与实现显示文摘为减少电力系统中断路器投切无功补偿电容器组时产生的电磁暂态效应,研究了一种配永磁机构的真空断路器同步分合闸控制系统:给出了中性点不接地星形方式连接的并联电容器组的同步分合闸控制策略,以数字信号处理器(DSP)为核心设计了同步分合闸控制系统的原理样机,给出了同步分合闸控制算法流程。通过分析影响永磁机构动作时间的因素,研究了同步分合闸控制的关键技术,包括设计FIR数字滤波器以准确提取系统电压电流过零点、径向基函数神经网络(RBF)预测控制、机构老化与触头磨损的自适应补偿控制等。最后给出并分析了同步分合闸控制精度的实验结果。实验结果表明,同步分合闸操作时的动作分散性基本保持在±0.5ms以内。张庆杰 袁海文 2010电力自动化设备2010,30,3:29
6分子光谱法无损鉴别生药材的最新进展显示文摘本文叙述了傅里叶变换拉曼光谱技术 (FT-Ram an) 和漫反射傅里叶变换红外光谱技术 (DR-FTIR)孙素琴 郁监源 胡鑫尧 1999光谱学与光谱分析1999,19,6:30
7Cytological, physiological, and transcriptomic analyses of golden leaf coloration in Ginkgo biloba L显示文摘Ginkgo biloba is grown worldwide as an ornamental plant for its golden leaf color.However,the regulatory mechanism of leaf coloration in G.biloba remains unclear.Here,we compared G.biloba gold-colored mutant leaves and normal green leaves in cytological,physiological and transcriptomic terms.We found that chloroplasts of the mutant were fewer and smaller,and exhibited ruptured thylakoid membranes,indistinct stromal lamellae and irregularly arranged vesicles.Physiological experiments also showed that the mutant had a lower chlorophyll,lower flavonoid and higher carotenoid contents(especially lutein).We further used transcriptomic sequencing to identify 116 differentially expressed genes(DEGs)and 46 transcription factors(TFs)involved in chloroplast development,chlorophyll metabolism,pigment biosynthesis and photosynthesis.Among these,the chlorophyll biosynthesis-related PPO showed down-regulation,while chlorophyll degradation-related NYC/NOL had up-regulated expression in mutant leaves.Z-ISO,ZDS,and LCYE,which are involved in carotenoid biosynthesis were up-regulated.Quantitative real-time PCR(RT-qPCR)further confirmed the altered expression levels of these genes at three stages.The alteration of PPO and NYC/NOL gene expression might affect chlorophyll biosynthesis and promote degradation of chlorophyll b to chlorophyll a,while the up-regulated genes Z-ISO,ZDS and LCYE enhanced carotenoid accumulation.Consequently,changes in the ratio of carotenoids to chlorophylls were the main factors driving the golden leaf coloration in the mutant G.biloba.Wei-xing Li Shun-bo Yang Zhaogeng Lu Zhi-chong He Yun-ling Ye Bei-bei Zhao Li Wang Biao Jin 2018Horticulture Research2018,5,1:28
8用FIR数字滤波器实现高精度时延的一种新方法显示文摘本文提供了一种实现高精度、连续可变数字时延的新方法。该方法利用FIR数字滤波器的线性相位特性,通过调节权向量,可连续改变信号时延。具有时延精度高、运算量小、可实现宽带时延等显著特点。该方法可用于宽带数字波束形成、自适应时延估计以及目标回波的时域分析等技术领域。本文对该方法的基本原理、设计方法及仿真结果进行了阐述,并给出了有关应用实例。马远良 赵俊渭 张全 1995声学学报1995,20,2:25
9FIR数字滤波器的递推最小二乘设计算法显示文摘本文考虑对称系数及反对称系数的FIR数字滤波器的设计问题,设计准则选为最小加权平方误差准则,并将这个设计问题看成一个线性系统的辨识问题,辨识系统参数所需的输入数据由一随机抽样法产生,辨识算法采用递推最小二乘法.按随机抽样法产生的数据具有很强的激励,保证了被辨识参数的收敛性,同时又自然地实现了最小加权平方误差准则.两个设计范例说明了本文提出的设计方法的有效性.赖晓平 1999信号处理1999,15,3:25
10长三角城市群金融发展对经济增长促进作用的实证分析——基于动态计量经济学分析方法的应用显示文摘长三角城市群的金融体系充分发挥金融功能,促进了该地区经济的“质”与“量”的提升。格兰杰因果关系检验、VAR模型、脉冲响应函数、方差分析等一系列动态计量经济学实证分析结果也证明了金融发展促进了长三角城市群的经济增长。实证结果表明,这种推动作用是从增量调整进行到存量调整的;是有滞后期的,但是可以持续较长时间。金融发展对经济增长的影响不仅仅体现在存量上,更体现在增量上,是该地区金融效率提高的表现。深化金融体制改革,提高金融市场化,不断提高金融体系的效率,充分发挥金融体系的功能,以金融发展带动经济增长,实现经济金融良性互动,提高区域乃至国家的竞争力,长三角城市群无疑为我国其他地区树立了良好的榜样,提供了崭新的思路。叶耀明 王胜 2007经济问题探索2007,,4:22
11关于希尔伯特变换的分析和研究显示文摘首先从数学定义上直观地分析希尔伯特变换 ,接着讨论了离散希尔伯特变换的基本原理 ,并研究如何利用有限冲激响应滤波器 ( FIR)设计方案来实现该变换。最后 ,举例说明希尔伯特变换在数字 I-Q下变频器中的应用 。颜彪 杨娟 2004电气电子教学学报2004,26,5:17
12网络流量预测方法和实际预测分析显示文摘随着网络带宽的迅速增加以及各种网络服务的广泛应用,针对网络流量的建模以及预测日益重要并备受人们关注。为了更好地对网络流量进行建模和预测,文章一方面将现有的一些流量模型分短相关和长相关两类进行总结和分析;另一方面分析了常见的流量预测方法,尤其是神经网络、模糊理论以及小波分析。并在实际测量中,使用FIR神经网络模型对网络流量进行了实际的预测。最后,提出了流量预测在网络安全领域的应用前景和方向。郑成兴 2006计算机工程与应用2006,42,23:16
13基于FPGA的软件无线电接收平台设计显示文摘软件无线电的中心思想是构成一个具有开放性、标准化、模块化的通用的硬件平台,通过加载相应的软件就可实现不同平台、不同系统之间的互联和兼容,是通信系统摆脱了硬件系统结构的束缚。进行了matlab的算法仿真之后,采用ALTERA公司的CycloneIIIFPGA芯片作为数字信号处理的核心器件,考虑到带宽、采样率、分辨率因素,选择ADS5547作为中频数字化前端的ADC部件,用VerilogHDL语言对该平台进行了设计开发。在硬件平台上完成了A/D采样,数字解调输出等部分,实现了调频和调幅广播的解调,验证了该硬件平台的正确性,而且系统具有灵活性、可重置性和可扩展性。郑涛 王丹志 施璟 郭希 焦凌霄 张鹏 2013软件2013,34,4:16
14不同坡位杉木樟树混交林地上部分和地下部分生物量分布显示文摘对福建省尤溪县4年生杉木、樟树人工混交林地上部分和地下部分生物量及其分配进行了调查。结果表明,从混交林生长指标来看,不同坡位杉木及樟树平均胸径、平均树高及单位面积平均材积均体现为下坡位生长量>中坡位生长量>上坡位生长量;从生物量来看,下坡位杉木、樟树平均木单株总生物量最高,其次为中坡位,上坡位杉木、樟树林分总生物量最低;从各器官生物量分配率上看,不同坡位杉木各器官生物量分配率均表现为干部>叶部>枝部,樟树各器官生物量均表现为干部>枝部>叶部。从平均木各径级根生物量分配率来看,杉木不同坡位均表现为骨骼根>中根>大根>小根>细根,樟树不同坡位均表现为骨骼根>大根>中根>细根>小根。张章秀 2010江西农业学报2010,22,8:14
15基于DSP的数字信号处理实验设计显示文摘针对数字信号处理及DSP技术教学中的困难,设计1个FIR数字滤波的综合实验。采用窗函数法,借助Matlab程序设计语言,设计FIR数字滤波器,应用DSP汇编语言编程实现该滤波器。实践表明,该实验设计使学生能更好地理解和掌握该课程的基本理论,并能提高学生的工程应用能力,提高本课程的授课效果,提高学生分析问题、解决问题和动手能力,使学生通过本课程的学习更加适应工作的需要。郝小江 缪志农 黄昆 2012实验技术与管理2012,29,2:14
16采样信号的数字滤波设计和DSP实现显示文摘针对基于DSP的采样装置,以FIR滤波器为例,讨论对采样数字信号的数字滤波设计和DSP实现,同时讨论了用Matlab软件设计数字滤波器的方法。陈明军 王金 2006信息技术2006,30,1:13
17Disassembly of the fruit cell wall by the ripening-associated polygalacturonase and expansin influences tomato cracking显示文摘Fruit cracking is an important problem in horticultural crop production.Polygalacturonase(SlPG)and expansin(SlEXP1)proteins cooperatively disassemble the polysaccharide network of tomato fruit cell walls during ripening and thereby,enable softening.A Golden 2-like(GLK2)transcription factor,SlGLK2 regulates unripe fruit chloroplast development and results in elevated soluble solids and carotenoids in ripe fruit.To determine whether SlPG,SlEXP1,or SlGLK2 influence the rate of tomato fruit cracking,the incidence of fruit epidermal cracking was compared between wild-type,Ailsa Craig(WT)and fruit with suppressed SlPG and SlEXP1 expression(pg/exp)or expressing a truncated nonfunctional Slglk2(glk2).Treating plants with exogenous ABA increases xylemic flow into fruit.Our results showed that ABA treatment of tomato plants greatly increased cracking of fruit from WT and glk2 mutant,but not from pg/exp genotypes.The pg/exp fruit were firmer,had higher total soluble solids,denser cell walls and thicker cuticles than fruit of the other genotypes.Fruit from the ABA treated pg/exp fruit had cell walls with less water-soluble and more ionically and covalently-bound pectins than fruit from the other lines,demonstrating that ripening-related disassembly of the fruit cell wall,but not elimination of SlGLK2,influences cracking.Cracking incidence was significantly correlated with cell wall and wax thickness,and the content of cell wall protopectin and cellulose,but not with Ca^(2+)content.Fangling Jiang Alfonso Lopez Shinjae Jeon Sergio Tonetto de Freitas Qinghui Yu Zhen Wu John M.Labavitch Shengke Tian Ann L.T.Powell Elizabeth Mitcham 2019Horticulture Research2019,6,1:13
18A method for the production and expedient screening of CRISPR/Cas9-mediated non-transgenic mutant plants显示文摘Developing CRISPR/Cas9-mediated non-transgenic mutants in asexually propagated perennial crop plants is challenging but highly desirable.Here,we report a highly useful method using an Agrobacterium-mediated transient CRISPR/Cas9 gene expression system to create non-transgenic mutant plants without the need for sexual segregation.We have also developed a rapid,cost-effective,and high-throughput mutant screening protocol based on Illumina sequencing followed by high-resolution melting(HRM)analysis.Using tetraploid tobacco as a model species and the phytoene desaturase(PDS)gene as a target,we successfully created and expediently identified mutant plants,which were verified as tetra-allelic mutants.We produced pds mutant shoots at a rate of 47.5%from tobacco leaf explants,without the use of antibiotic selection.Among these pds plants,17.2%were confirmed to be non-transgenic,for an overall non-transgenic mutation rate of 8.2%.Our method is reliable and effective in creating non-transgenic mutant plants without the need to segregate out transgenes through sexual reproduction.This method should be applicable to many economically important,heterozygous,perennial crop species that are more difficult to regenerate.Longzheng Chen Wei Li Lorenzo Katin-Grazzini Jing Ding Xianbin Gu Yanjun Li Tingting Gu Ren Wang Xinchun Lin Ziniu Deng Richard J.McAvoy Frederick G.Gmitter Jr. Zhanao Deng Yunde Zhao Yi Li 2018Horticulture Research2018,5,1:12
19Recovery of the gravity field from GOCE data by using the invariants of gradient tensor显示文摘The gravity field models GUCAS_EGM and GUCAS_EGM_DL are established from GOCE data (GOCE Level 2 Products from Nov. 1 to Dec. 31, 2009) based on the method of the invariants of the gravity gradient tensor, where GUCAS_EGM is derived after GOCE gravity gradient data are filtered with FIR, and GUCAS_EGM_DL is computed with an additional Durbin-Levison arithmetic apart from FIR. Since this method, different from current programs dealing with GOCE data, is introduced for the first time, some new problems are required to be discussed in advance; for example, how to filter GOCE gravity gradient data, how to compute the invariants of the gradient tensor, and how to deal with the pole gap and so on. In addition, by comparing our models with ones recommended by ESA, it can be seen that the variations of GUCAS_EGM and the models recommended by ESA to EGM08 are almost equivalent, and the variation of GUCAS_EGM_DL to EGM08 is obviously less than ones of the recommended models.YU JinHai WAN XiaoYun 2013Science China Earth Sciences2013,56,7:11
20FIR数字滤波器的最优化设计及MATLAB实现显示文摘尽管窗函数法与频率抽样法在FIR数字滤波器的设计中有着广泛的应用,但两者都不是最优化的设计。介绍了一种基于等波纹切比雪夫逼近准则的FIR数字滤波器的最优化设计方法,通过MATLAB的仿真实现,证明了该方法是一种最优化的设计。黎雄 张学智 2004信息技术2004,28,10:11
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