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Chinese Physics B 2012年第9期21卷 224-228页

作者：武寄洲马杰姬中华张一驰李玉清汪丽蓉赵延霆肖连团贾锁堂 state key {2. of Quantum Optics and Quantum Optics Devices Laser Spectroscopy LaboratoryCollege of Physics and Electronic EngineeringShanxi University

We propose a technique to precisely measure the line width of the photoassociation spectra of the excited cesium molecule by using a frequency shifter to generate two laser beams with a precise frequency difference. A series of photoassociation （PA） spectra are recorded with two laser beam induced molecular lines, whose peak separation serves as an accurate frequency ruler to measure the line width of the PA spectra. The full width half maximum line width was studied as a function of PA laser intensity. The extrapolated value at zero laser intensity is （34.8± 0.2.） MHz. By analyzing other broadening mechanisms, a value of （32.02.± 0.70） MHz was deduced. It is shown that this scheme is inexpensive, simple, robust, and is promising for applications in a variety of other atomic species.

关键词： laser cooling molecular spectroscopy line shapes and width

Transient stochastic response of quasi integerable Hamiltonian systems

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Acta Mechanica Sinica 2013年第4期29卷 602-611页

作者： zhong-hua Liu Jian-hua Geng Wei-Qiu Zhu Department of Civil Engineering Xiamen University Department of Mechanics State Key Laboratory of Fluid Power Transmission and Control Zhejiang University

The approximate transient response of quasi in- tegrable Hamiltonian systems under Gaussian white noise excitations is investigated. First, the averaged It6 equa- tions for independent motion integrals and the associated Fokker-Planck-Kolmogorov （FPK） equation governing the transient probability density of independent motion integrals of the system are derived by applying the stochastic averag- ing method for quasi integrable Hamiltonian systems. Then, approximate solution of the transient probability density of independent motion integrals is obtained by applying the Galerkin method to solve the FPK equation. The approxi- mate transient solution is expressed as a series in terms of properly selected base functions with time-dependent coeffi- cients. The transient probability densities of displacements and velocities can be derived from that of independent mo- tion integrals. Three examples are given to illustrate the ap- plication of the proposed procedure. It is shown that the re- suits for the three examples obtained by using the proposed procedure agree well with those from Monte Carlo simula- tion of the original systems.

关键词： Transient response ~ Stochastic averagingmethod ~ Galerkin method ~ Quasi integrable Hamiltoniansystem

Residual-Based False Data Injection Attacks Against Multi-Sensor Estimation Systems

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IEEE/CAA Journal of Automatica Sinica 2023年第5期10卷 1181-1191页

作者： Haibin Guo Jian Sun zhong-hua Pang the National key laboratory of Autonomous Intelligent Unmanned Systems School of AutomationBeijing Institute of TechnologyBeijing 100081China the Beijing Institute of technology Chongqing Innovation Center Chongqing 401120China the key laboratory of Fieldbus {2. and Automation of Beijing North China University of TechnologyBeijing 100144China

This paper investigates the security issue of multisensor remote estimation *** optimal stealthy false data injection(FDI)attack scheme based on historical and current residuals,which only tampers with the measurement residuals of partial sensors due to limited attack resources,is proposed to maximally degrade system estimation *** attack stealthiness condition is given,and then the estimation error covariance in compromised state is derived to quantify the system performance under *** optimal attack strategy is obtained by solving several convex optimization problems which maximize the trace of the compromised estimation error covariance subject to the stealthiness ***,due to the constraint of attack resources,the selection principle of the attacked sensor is provided to determine which sensor is attacked so as to hold the most impact on system ***,simulation results are presented to verify the theoretical analysis.

关键词： Cyber-physical systems(CPSs) false data injection(FDI)attacks remote state estimation stealthy attacks

ON EIGENVALUE BOUNDS AND ITERATION METHODS FOR DISCRETE ALGEBRAIC RICCATI EQUATIONS

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Journal of Computational Mathematics 2011年第3期29卷 341-366页

作者： hua Dai zhong-Zhi Bai Department of Mathematics Nanjing University of Aeronautics and Astronautics Nanjing 210016 China LSEC ICMSEC Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100190 China

We derive new and tight bounds about the eigenvalues and certain sums of the eigenvalues for the unique symmetric positive definite solutions of the discrete algebraic Riccati equations. These bounds considerably improve the existing ones and treat the cases that have been not discussed in the literature. Besides, they also result in completions for the available bounds about the extremal eigenvalues and the traces of the solutions of the discrete algebraic Riccati equations. We study the fixed-point iteration methods for com- puting the symmetric positive definite solutions of the discrete algebraic Riccati equations and establish their general convergence theory. By making use of the Schulz iteration to partially avoid computing the matrix inversions, we present effective variants of the fixed-point iterations, prove their monotone convergence and estimate their asymptotic convergence rates. Numerical results show that the modified fixed-point iteration methods are feasible and effective solvers for computing the symmetric positive definite solutions of the discrete algebraic Riccati equations.

关键词： Discrete algebraic Riccati equation Symmetric positive definite solution Eigenvalue bound Fixed-point iteration Convergence theory.

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一体化摩擦电自供能气湿传感器研究进展

电子学报 2024年第2期52卷 660-677页

作者：刘勃豪谢光忠段再华袁震蒋亚东太惠玲电子科技大学光电科学与工程学院电子薄膜与集成器件国家重点实验室四川成都611731

气湿传感器在环境检测、工农业生产以及医疗健康等领域应用甚广,然而主流的电阻、电容、光电气湿传感器需要外部供能工作,一方面电池的频繁更换与维护增加了泄露引起的环境污染,另一方面传感器对外界能源过于依赖将限制其在缺乏能源的... 详细信息

气湿传感器在环境检测、工农业生产以及医疗健康等领域应用甚广,然而主流的电阻、电容、光电气湿传感器需要外部供能工作,一方面电池的频繁更换与维护增加了泄露引起的环境污染,另一方面传感器对外界能源过于依赖将限制其在缺乏能源的场合中正常工作.鉴于此,通过赋予气湿传感器自发收集外界环境能量并转化成电能的能力,以实现长期自主工作的自供能气湿传感器的理念应运而生.摩擦纳米发电机(TriboElectric NanoGenerator,TENG)作为一种新型能量俘获装置,由于其成本低、可结构设计且能量转换效率高等优势,在机械能收集与自供能传感器等领域应用广泛.进一步赋予TENG外界信息感知的能力,可实现单一器件兼具能量收集与气体敏感的功能,这种一体化摩擦电自供能传感器是目前传感器领域发展的一个热点方向.本文对一体化摩擦电自供能气湿传感器的研究现状与最新进展进行了综述,可从以下三个方面进行概括.(1)一体化摩擦电气湿传感器工作原理与气敏机理,并基于TENG的等效电路模型论述了影响敏感性能的参数—介电层摩擦电荷密度、介电层介电常数与电极层电导率;(2.一体化摩擦电气体传感器的研究进展,根据检测对象将其主要分为氨气(Ammonia,NH3)、乙醇以及其他有机挥发化合物(Volatile Organic Compound,VOC)气体传感器,介绍了其在呼出气、食品变质以及尾气排放检测场合的应用;(3)一体化摩擦电湿度传感器的研究进展,根据湿度对输出电信号幅值影响的不同将其主要分为电信号下降型传感器与电信号上升型传感器,介绍了其在非接触开关、皮肤湿度与尿不湿检测场合的应用.最后对一体化摩擦电气湿传感器的研究现状与面临的问题挑战进行了总结,并对其未来的发展方向进行了展望,可为相关研究提供参考.

关键词：摩擦纳米发电机一体化自供能敏感机理气体传感器湿度传感器

The Secondary Metabolites of Plant Endophyte Streptomyces *** 63342

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The Secondary Metabolites of Plant Endophyte Streptomyces **...

SuperFeat:Quantitative Feature Learning from Single-cell RNA-seq Data Facilitates Drug Repurposing

多学科交叉，产学研联合，实现西部药用植物资源的可持续利用——第十届全国药用植物及植物药学术研讨会

作者： YANG Xue-Qiong~1,YANG Ya-Bin~1,DING zhong-Tao~(1*),ZHANG Yong~1,YANG Zhi, ZHOU Hao~1,HE Guang-Wei~1,huaNG Rong~1,ZHAO Li-Xing~2.XU Li-hua~2.1 key laboratory of Medicinal Chemistry for Natural Resource,Ministry of Education, School of Chemical science and technology,Yunnan university,Kunming 650091, china 2.Yunnan Institute of Microbiology,Yunnan university,Kunming 650091,china

One new sesquiterpene glycoside and one new cyclodipeptide were isolated from the fermentation broth of Streptomyces *** their structures were determined as 3R,5S,6S, 9R-tetrhydroxymegastigman-7-en-9-O-β-D-apiofuranosyl-(1→2.-β-D-glucopyranoside(1)and cyclo(L-Pro-L-Omet)(2.,together with six known compounds as tyramine acetate(3)[1],

关键词：

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Genomics, Proteomics & Bioinformatics 2024年第3期22卷 91-105页

作者： Jianmei zhong Junyao Yang Yinghui Song Zhihua Zhang Chunming Wang Renyang Tong Chenglong Li Nanhui Yu Lianhong Zou Sulai Liu Jun Pu Wei Lin state key {2. for Oncogenes and Related Genes Department of CardiologyRenji HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai Cancer InstituteShanghai 200127China Department of laboratory Medicine Xin Hua HospitalSchool of MedicineShanghai Jiao Tong UniversityShanghai 200092China Central laboratory of Hunan Provincial People’s Hospital/The First Affiliated Hospital of Hunan Normal university Changsha 410005China

In this study,we devised a computational framework called Supervised Feature Learning and Scoring(SuperFeat)which enables the training of a machine learning model and evaluates the canonical cellular statuses/features in pathological tissues that underlie the progression of *** framework also enables the identification of potential drugs that target the presumed detrimental cellular *** framework was constructed on the basis of an artificial neural network with the gene expression profiles serving as input *** training data comprised single-cell RNA sequencing datasets that encompassed the specific cell lineage during the developmental progression of cell features.A few models of the canonical cancer-involved cellular statuses/features were tested by such ***,we illustrated the drug repurposing pipeline,utilizing the training parameters derived from the adverse cellular statuses/features,which yielded successful validation results both in vitro and in *** is accessible at https://***/weilin-genomics/rSuperFeat.

关键词： Single-cell transcriptomics Cell state transition Cell scoring Drug search Feature learning

Critical Dimension for Stable Self-Gravitating Stars in AdS

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Communications in Theoretical Physics 2009年第8期52卷 255-260页

作者： LI zhong-hua CAI Rong-Gen Department of Physics China West Normal University Nanchong 637002 China key laboratory of Frontiers in Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences P.O. Box 2735 Beijing 100190 China

We study the self-gravitating stars with a linear equation of state, P = aρ, in AdS space, where a is a constant parameter. There exists a critical dimension, beyond which the stars are always stable with any central energy density; below which there exists a maximal mass configuration for a certain central energy density and when the central energy density continues to increase, the configuration becomes unstable. We find that the critical dimension depends on the parameter a, it runs from d = 11.142. to 10.12.1 as a varies from a = 0 to 1. The lowest integer dimension for a dynamically stable self-gravitating configuration should be d = 12.for any a E [0, 1] rather than d = 11, the latter is the case of self-gravitating radiation configurations in AdS space.

关键词： critical dimension self-gravitating star AdS space

An integrated pest management program for managing fusarium head blight disease in cereals

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Journal of Integrative Agriculture 2022年第12期21卷 3434-3444页

作者： CHEN A-hai Tofazzal ISLAM MA zhong-hua state key {2. of Rice Biology/key {2. of Molecular Biology of Crop Pathogens and Insects Institute of BiotechnologyZhejiang UniversityHangzhou 310058P.R.China Institute of Biotechnology and Genetic Engineering(IBGE) Bangabandhu Sheikh Mujibur Rahman Agricultural UniversityGazipur 1706Bangladesh

Fusarium head blight(FHB)is a worldwide devastating disease of small grain cereals and Fusarium graminearum species complex(FGSC)is the major pathogen causing the *** epidemics of FHB lead to the reduction of grain yield and economic ***,mycotoxins produced by the FHB pathogens are hazardous to the health of human and *** this review,we summarize the epidemiology of FHB,and introduce effects of this disease on economy,environment and food *** focus on the integrated management approaches for controlling FHB including agronomic practices,resistant cultivars,chemical control,and *** addition,we also discuss the potential novel management strategies against FHB and mycotoxin.

关键词： fusarium head blight Fusarium graminearum integrated pest management program mycotoxins

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亚微细硬质合金三牙轮钻齿的使用与失效分析

武汉理工大学学报 2004年第12期26卷 16-19页

作者：杨汉民周建胡中彪余立新张烈华武汉理工大学材料复合新技术国家重点实验室武汉430070 江钻股份新材料事业部潜江433124

将钴含量为 13%的亚微细晶粒硬质合金钻齿应用到 81/ 2.XA5 37三牙轮钻头上 ,并运用扫描电镜和光学显微镜等手段对亚微细晶粒硬质合金钻齿进行了失效分析。分析发现 81/ 2.XA5 37钻头的主要失效形式为崩齿和断齿。在断口分析的基础上 ,... 详细信息

将钴含量为 13%的亚微细晶粒硬质合金钻齿应用到 81/ 2.XA5 37三牙轮钻头上 ,并运用扫描电镜和光学显微镜等手段对亚微细晶粒硬质合金钻齿进行了失效分析。分析发现 81/ 2.XA5 37钻头的主要失效形式为崩齿和断齿。在断口分析的基础上 ,提出了亚微细硬质合金断裂机理为沿晶断裂 ,而常规硬质合金的断裂机理为穿晶断裂。由于生产工艺问题亚微细合金内部存在粗大的 WC晶粒、晶粒偏析以及微裂纹 ,这些内部缺陷的存在使亚微细合金出现早期失效。

关键词：亚微细晶粒硬质合金扫描电镜失效分析