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Communications in Theoretical Physics 2002年第10期38卷 395-399页

作者： ZHANG Jie-Fang chen feng-juan College of Mathematics Physics and Information Zhejiang Normal University Jinhua 321004 China Institute of Nonlinear Physics Zhejiang Normal University Jinhua 321004 China College of Mathematics Physics and Information Zhejiang Normal University Jinhua 321004 China

Using the extended homogenous balance method, we obtainabundant exact solution structures ofa (2+1)dimensional integrable model, the generalized Nizhnik-Novikov-Veselov equation. By means of the leading order termanalysis, the nonlinear transformations of generalized Nizhnik-Novikov-Veselov equation are given first, and then somespecial types of single solitary wave solution and the multisoliton solutions are constructed.

关键词： extended homogeneous balance method, (2+1) dimensions, NNV equation, soliton solutions

Genomic Epidemiology of Imported Cases of COVID-19 in Guangdong Province,China,October 2020–May 2021

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Biomedical and Environmental Sciences 2022年第5期35卷 393-401页

作者： LIANG Dan WANG Tao LI Jiao Jiao GUAN Da Wei ZHANG Guan Ting LIANG Yu feng LI An An HONG Wen Shan WANG Li chen Meng Lin DENG Xiao Ling chen feng juan PAN Xing Fei JIA Hong Ling LEI Chun Liang KE Chang Wen Guangdong Provincial Key Laboratory of Virology Institute of Medical MicrobiologyJinan UniversityGuangzhou 510632GuangdongChina Guangzhou National Laboratory Guangzhou 510700GuangdongChina Guangdong Provincial Center for disease control and prevention Guangdong Workstation for Emerging Infectious Disease Control and PreventionGuangzhou 511430GuangdongChina Shantou University Medical College Shantou 515041GuangdongChina Guangzhou Eighth People’s Hospital Guangzhou 510030GuangdongChina School of public health Sun Yat-sen UniversityGuangzhou 510080GuangdongChina School of Public Health Southern Medical UniversityGuangzhou 510515GuangdongChina Guangzhou Mendel Genomics and Medical Technology Co. Ltd.Guangzhou 510535GuangdongChina Department of Infectious Diseases the Third Affiliated Hospital of Guangzhou Medical UniversityGuangzhou 510150GuangdongChina Department of Medical Biochemistry and Molecular Biology School of MedicineJinan UniversityGuangzhou 510632GuangdongChina

Objective The pandemic of severe acute respiratory syndrome coronavirus 2(SARS-Co V-2) has been engendering enormous hazards to the world. We obtained the complete genome sequences of SARSCo V-2 from imported cases admitted to the Guangzhou Eighth People’s Hospital, which was appointed by the Guangdong provincial government to treat coronavirus disease 2019(COVID-19). The SARS-Co V-2 diversity was analyzed, and the mutation characteristics, time, and regional trend of variant emergence were *** In total, 177 throat swab samples were obtained from COVID-19 patients(from October2020 to May 2021). High-throughput sequencing technology was used to detect the viral sequences of patients infected with SARS-Co V-2. Phylogenetic and molecular evolutionary analyses were used to evaluate the mutation characteristics and the time and regional trends of *** We observed that the imported cases mainly occurred after January 2021, peaking in May2021, with the highest proportion observed from cases originating from the United States. The main lineages were found in Europe, Africa, and North America, and B.1.1.7 and B.1.351 were the two major sublineages. Sublineage B.1.618 was the Asian lineage(Indian) found in this study, and B.1.1.228 was not included in the lineage list of the Pangolin web. A reasonably high homology was observed among all samples. The total frequency of mutations showed that the open reading frame 1 a(ORF1 a) protein had the highest mutation density at the nucleotide level, and the D614 G mutation in the spike protein was the commonest at the amino acid level. Most importantly, we identified some amino acid mutations in positions S, ORF7 b, and ORF9 b, and they have neither been reported on the Global Initiative of Sharing All Influenza Data nor published in Pub Med among all missense *** These results suggested the diversity of lineages and sublineages and the high homology at the amino acid level among imported case

关键词： Severe acute respiratory syndrome coronavirus 2 Next-Generation sequencing Phylogenetic tree Variants

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不相容决策表求核方法

计算机工程与设计 2012年第3期33卷 1187-1191页

作者：陈凤娟辽宁对外经济贸易学院信息技术系辽宁大连116052

通过分析不相容决策表,提出相容核与不相容核的概念。分析了3个不相容决策表中的相容核与不相容核,比较了几种现有的不相容决策表的求核方法,这些方法有的不能完全求出相容核与不相容核,有的不能把得到的相容核与不相容核区分开。针对... 详细信息

通过分析不相容决策表,提出相容核与不相容核的概念。分析了3个不相容决策表中的相容核与不相容核,比较了几种现有的不相容决策表的求核方法,这些方法有的不能完全求出相容核与不相容核,有的不能把得到的相容核与不相容核区分开。针对这一问题,对HU差别矩阵进行改进,得到两个新的差别矩阵,这两个矩阵能分别计算出相容核与不相容核。

关键词：不相容决策表相容核不相容核差别矩阵求核方法

基于改进MCFT的GFRP-RC梁抗剪承载力分析

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工程力学 2023年第8期40卷 36-46页

作者：宋博金浏陈凤娟杜修力北京工业大学城市减灾与防灾防护教育部重点实验室北京100124

通过三维细观数值模拟方法,建立了大尺寸GFRP筋混凝土(GFRP-RC)梁剪切破坏力学分析模型,研究了剪跨比、纵筋率和梁深对GFRP-RC梁裂缝倾角及荷载-位移曲线的影响规律。并以修正压力场理论(MCFT)为基础,根据剪切裂缝宽度沿梁深变化的特点... 详细信息

通过三维细观数值模拟方法,建立了大尺寸GFRP筋混凝土(GFRP-RC)梁剪切破坏力学分析模型,研究了剪跨比、纵筋率和梁深对GFRP-RC梁裂缝倾角及荷载-位移曲线的影响规律。并以修正压力场理论(MCFT)为基础,根据剪切裂缝宽度沿梁深变化的特点,建立了考虑裂缝宽度沿梁深变化的平均裂缝宽度计算模型,提高了修正压力场简化公式的计算精度。鉴于此,提出能考虑剪跨比及大尺寸影响的无腹筋GFRPRC梁抗剪承载力计算方法,并通过213组试验和模拟数据验证其合理性及准确性。与规范计算结果相比较,结果表明,本文所建立的平均裂缝宽度计算模型合理有效,基于此得到的MCFT简化公式能较好的预测大尺寸无腹筋GFRP-RC梁的抗剪承载力,为GFRP-RC梁的抗剪设计提供了理论参考和方法。

关键词：大尺寸GFRP筋混凝土梁改进MCFT 抗剪承载力细观模拟尺寸效应

Bioinspired Passive Tactile Sensors Enabled by Reversible Polarization of Conjugated Polymers

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Nano-Micro Letters 2025年第1期17卷 361-377页

作者： feng He Sitong chen Ruili Zhou Hanyu Diao Yangyang Han Xiaodong Wu School of Mechanical Engineering Sichuan UniversityChengdu 610065People’s Republic of China School of Software Engineering Chongqing University of Posts and TelecommunicationsChongqing 400065People’s Republic of China State Key Laboratory of Polymer Materials Engineering Sichuan UniversityChengdu 610065People’s Republic of China

Tactile perception plays a vital role for the human body and is also highly desired for smart prosthesis and advanced *** to active sensing devices,passive piezoelectric and triboelectric tactile sensors consume less power,but lack the capability to resolve static ***,we address this issue by utilizing the unique polarization chemistry of conjugated polymers for the first time and propose a new type of bioinspired,passive,and bio-friendly tactile sensors for resolving both static and dynamic ***,to emulate the polarization process of natural sensory cells,conjugated polymers(including poly(3,4-ethylenedioxythiophen e):poly(styrenesulfonate),polyaniline,or polypyrrole)are controllably polarized into two opposite states to create artificial potential *** controllable and reversible polarization process of the conjugated polymers is fully in situ ***,a micro-structured ionic electrolyte is employed to imitate the natural ion channels and to encode external touch stimulations into the variation in potential difference *** with the currently existing tactile sensing devices,the developed tactile sensors feature distinct characteristics including fully organic composition,high sensitivity(up to 773 mV N^(−1)),ultralow power consumption(nW),as well as superior *** demonstrations,both single point tactile perception(surface texture perception and material property perception)and two-dimensional tactile recognitions(shape or profile perception)with high accuracy are successfully realized using self-defined machine learning *** tactile sensing concept innovation based on the polarization chemistry of conjugated polymers opens up a new path to create robotic tactile sensors and prosthetic electronic skins.

关键词： Passive tactile sensors Reversible polarization of conjugated polymers Tactile perception Machine learning algorithm Object recognition

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粗糙集信息观中的绝对约简

计算机工程与科学 2010年第5期32卷 97-99,149页

作者：陈凤娟孙静辽宁对外经贸学院信息技术系辽宁大连116052

绝对约简是粗糙集理论研究的基本内容之一,而在粗糙集的信息观中,绝对约简的相关定理还存在着一些不足。本文分析了现有的一些关于划分与知识信息熵的关系定理以及绝对约简的充要条件定理,提出新的关于划分和条件信息熵的对应关系定理,... 详细信息

绝对约简是粗糙集理论研究的基本内容之一,而在粗糙集的信息观中,绝对约简的相关定理还存在着一些不足。本文分析了现有的一些关于划分与知识信息熵的关系定理以及绝对约简的充要条件定理,提出新的关于划分和条件信息熵的对应关系定理,并给出其证明过程;依据该定理提出新的粗糙集信息观的绝对约简的充要条件,并给出相关证明。

关键词：粗糙集信息熵条件信息熵绝对约简

剪跨比对CFRP加固RC剪力墙抗剪承载力及加固效率影响分析

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工程力学 2024年第11期41卷 22-32页

作者：张滨麟陈凤娟金浏杜修力北京工业大学城市减灾与防灾防护教育部重点实验室北京100124

为探究剪跨比对外贴碳纤维增强聚合物(CFRP)布加固钢筋混凝土(RC)剪力墙抗剪性能及破坏机制的影响规律,建立了考虑Hashin损伤准则及Cohesive内聚力作用的三维数值模型。利用已有的试验数据验证了该文数值模拟方法的准确性,研究了剪跨比... 详细信息

为探究剪跨比对外贴碳纤维增强聚合物(CFRP)布加固钢筋混凝土(RC)剪力墙抗剪性能及破坏机制的影响规律,建立了考虑Hashin损伤准则及Cohesive内聚力作用的三维数值模型。利用已有的试验数据验证了该文数值模拟方法的准确性,研究了剪跨比对不同加固方式下剪力墙的破坏模式、抗剪承载力和延性系数等力学性能的影响,并进一步分析了剪跨比及加固方式对CFRP抗剪贡献及加固效率的影响规律。结果表明:随着剪跨比的增大,CFRP加固RC剪力墙的抗剪承载力降低,CFRP的抗剪贡献与加固效率被大幅削弱;此外,在同一剪跨比下,相较于双面加固及全包裹加固方式,采取水平条带加固剪力墙将提高1.0倍~3.0倍的抗剪承载力加固效率,延性系数提高效率增大0.8倍~2.4倍。

关键词：钢筋混凝土剪力墙 CFRP布加固剪跨比加固方式抗剪贡献加固效率

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Laser image refractive index sensor based on the combination of a coreless optical fiber and a digital camera

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Optoelectronics Letters 2025年第2期21卷 65-68页

作者： GUO Jingzhong LAN feng chen Xiang LIU Haifeng Xi'an Institute of Space Radio Technology Key Laboratory of Optoelectronic Sensor and Sensing Network Technology College of Electronic Information and Optical Engineering Nankai University

As a laser passes through a scattering medium,the light interacts with the irregular reflections within the medium,resulting in light scattering and the formation of *** this paper,an image sensor based on the combination of a coreless optical fiber and a digital camera is proposed for liquid refractive index sensing *** coreless fiber is used as a sensing unit,and the change in the speckle pattern is measured using the digital correlation method to detect the magnitude of the liquid's refractive *** experimental results indicate that the laser image sensing technique is capable of effectively distinguishing liquid samples with refractive indices ranging from 1.332 8 to1.390 8,with a sensing sensitivity of-1.306 ***,the laser image sensing technique,with its advantages of high experimental reproducibility,simple system design,remote over-control,holds great research significance and potential application in laser communication and sensor integration.

关键词： Digital cameras

超凸空间中的连续选择定理与耦合定理(英文)

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数学进展 2005年第5期34卷 614-618页

作者：陈凤娟沈自飞浙江师范大学数理学院金华浙江321004

本文给出了超凸空间中的连续选择定理与耦合定理,并得到了它们的证明. 作为应用,我们给出了超凸空间中的不动点定理与截口定理.

关键词：超凸空间连续选择定理耦合定理不动点定理