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QUANTIZATION COMMUTES WITH REDUCTION,A SURVEY

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Acta mathematica Scientia 2021年第6期41卷 1859-1872页

作者： Xiaonan ma Institut de mathématiques de Jussieu-Paris Rive Gauche Universitéde ParisUFR de MathématiquesCase 701275205Paris Cedex 13France

We review the themes relating to the proposition that“quantization commutes with reduction”([Q,R]=0),from symplectic manifolds to Cauchy-Riemann manifolds.

关键词： index theory Dirac operator geometric quantization

BDS/GPS deformation analysis of a long-span cable-stayed bridge based on colored noise filtering

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Geodesy and Geodynamics 2023年第2期14卷 163-171页

作者： Jun ma China Railway Siyuan Survey and Design Group Co. LTDWuhan 430079China School of Surveying and mapping Wuhan UniversityWuhan 430079China

Combining GPS and BDS technology to monitor the deformation of long-span railway bridges with stricter deformation control requirements is of significance to the safety and control of the bridge and the safety of railway *** studies have ignored the influence of coloured noise in the deformation time *** is not conducive to accurate deformation analysis of long-span railway ***,GPS,BDS and GPS/BDS monitoring data of Ganjiang Bridge located in Ganzhou city,Jiangxi Province,China are adopted in this paper to filter the coloured noise in the deformation time series by principal component analysis(PCA),and the influence of coloured noise on the deformation analysis results of railway bridge is *** experimental results show that the diurnal temperature difference causes the mid-span and the tower of the railway cable-stayed bridge to deform with a period of about one day in the vertical and longitudinal directions,*** colored noise will make the uncertainty of the deformation parameter estimation overly *** can significantly reduce the coloured noise,and thus reduce the uncertainty of deformation parameter estimation by about 73%.Moreover,the average difference between the daily periodic motion amplitudes of the monitoring points obtained by using GPS and BDS deformation time series is 1.65 *** use of GPS/BDS deformation time series is not only helpful to reduce the influence of coloured noise,but also can reduce the difference between amplitude analysis results obtained from GPS and BDS deformation time series.

关键词： Long-span railway bridges GNSS deformation monitoring Coloured noise PCA

ImaGE DENOISING VIA TIME-DELAY REGULARIZATION COUPLED NONLINEAR DIFFUSION EQUATIONS

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Journal of Computational mathematics 2020年第3期38卷 417-436页

作者： Qianting ma School of mathematics&Statistics Nanjing University of Information Science&TechnologyNanjing 210044China

A novel nonlinear anisotropic diffusion model is proposed for image denoising which can be viewed as a novel regularized model that preserves the cherished features of Perona-malik to some *** is characterized by a local dependence in the diffusivity which manifests计self through the presence of p(3:)-Laplacian and time-delay *** proposed model offers a new nonlinear anisotropic diffusion which makes it possible to effectively enhance the denoising capability and preserve the details while avoiding ***,the restored image is very clear and becomes more *** Galerkin^method,we establish the well-posedness in the weak *** experimentts illustrate that the proposed model appears to be overwhelmingly competitive in restoring the images corrupted by Gaussian noise.

关键词： Image denoising Galerkin's method Existence Uniqueness

Analysis of error in soot characterization using scattering-based techniques

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Particuology 2011年第3期9卷 210-214页

作者： Lin ma Department of Mechanical Engineering Clemson University Clemson SC29634-0921 USA

The increasing concern of the health and environmental effects of ultrafine soot particles emitted by modern combustion devices calls for new techniques to monitor such particles. Techniques based on light scattering represent one possible monitoring method. In this study, numerical simulations were conducted to examine the errors involved in soot characterization using light scattering techniques. Specifically, this study focused on examining the error caused by the approximate fractal scattering models based on the Rayleigh-Deybe-Gans theory （the RDG-FA model）. When the angular scattering properties were used to retrieve parameters of soot aggregates （the radius of gyration and the fractal dimension）, the RDG-FA method was observed to cause a relative error of -10% for a representative set of soot parameters. The effects of measurement uncertainties were also investigated. Our results revealed the pattern of the errors： the errors consisted of a relatively constant baseline error caused by the RDG-FA approximation and an error increasing with the measurement uncertainties. These results are expected to be useful in the analysis and interpretation of experimental data, and also in the determination of the accuracy and applicable range of scattering techniques

关键词： Soot characterization Fractal scattering

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阿片类药物诱导瘙痒的机制研究进展

中国药理学通报 2025年第1期41卷 29-34页

作者：马芳周培岚苏瑞斌军事医学研究院国家安全特需药品全国重点实验室北京100850 南京中医药大学药学院江苏南京210046

瘙痒是临床使用阿片类药物镇痛的患者普遍存在的严重不良反应之一。大量研究已经阐明阿片类药物的镇痛机制,但阿片类药物诱导瘙痒的机制尚不明确,瘙痒与镇痛之间的关系也模糊不清。目前的研究发现,阿片类药物作用于μ、κ及δ阿片受体后... 详细信息

瘙痒是临床使用阿片类药物镇痛的患者普遍存在的严重不良反应之一。大量研究已经阐明阿片类药物的镇痛机制,但阿片类药物诱导瘙痒的机制尚不明确,瘙痒与镇痛之间的关系也模糊不清。目前的研究发现,阿片类药物作用于μ、κ及δ阿片受体后,直接或间接影响瘙痒关键受体——胃泌素释放肽受体的功能,进而影响瘙痒信息传递。神经介素B、神经肽Y、B型利钠肽等神经肽,以及其他受体如瞬时受体电位香草素1受体、N-甲基-D-天冬氨酸受体、5-羟色胺受体等,在吗啡诱导的瘙痒中也具有重要作用。此外,阿片类药物所致瘙痒的预防和治疗也是围手术期吗啡镇痛的难点和热点之一。因此,明确瘙痒的具体发生机制,对寻找新的研究思路及预防和治疗阿片类药物诱导的瘙痒具有重要意义。

关键词：阿片类诱导的瘙痒瘙痒与镇痛瘙痒机制阿片受体胃泌素释放肽受体瘙痒治疗

Effects of Airfoil-probe Tubes on the Flow Field of a Compressor Cascade

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Journal of Thermal Science 2017年第4期26卷 321-330页

作者： ma Hongwei JIN Chao ZHAO Lianpeng ma Rong National Key Laboratory of Science and Technology on Aero-Engines Collaborative Innovation Center of Advanced Aero-EngineSchool of Energy&Power EngineeringBeihang UniversityBeijing100191China

To explore the effects of airfoil-probe tubes and its installment position on the flow field of the compressor cas- cade, and find out the mechanism that how the airfoil-probes affect the aerodynamic characteristics of the com- pressor cascade, this paper performed both numerical and experimcntal works on the same compressor cascade. The experiment mainly focused on the cases of low mach number （ma = 0.1）, and cases with different mach numbers （0.1, 0.3, 0.7） and different incidence angles （-5, 0, 5） are investigated by the numerical method. The case without the airfoil-probe tube was referenced as the baseline, and other three cases with the airfoil-probe tubes installed in different chordwise positions O0%, 50%, 70% of the chord length） were studied. The diameter of the airfoil-probe tube is 3ram, which is configured as 300% amplification of some particular airfoil-probe ac- cording to the geometrical similarity principle. The results show that the airfoil-probe tubes have a negative in- fluenc~ on the flow capacity of the cascade at all investigation points. The separations and the large scale stream- wise vortices that induced by the airfoil-probe tube on the pressure side cause most the losses at the high mach number. The influence of the airfoil-probe tube on the flow field in the vicinity of the pressure side surface is lo- cal separation at the low mach number. The airfoil-probe tubes also have a clearly effect on the leakage flow. It decreases the mass flow of the leakage flow and weakens the intensity of the leakage vortex, but enlarges the in- fluence area. The total pressure loss of the case that the tube is installed at the half chordwise position is generally lower than other cases especially at the high mach number, it can even decrease the losses compared with the ba- sic case.

关键词： airfoil-probe compressor cascade installment position 5-hole probe

Optical colorimetric sensor arrays for chemical and biological analysis

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Science China Chemistry 2018年第6期61卷 643-655页

作者： Yufan ma Yawen Li Kun ma Zhuo Wang Beijing Advanced Innovation Center for Soft matter Science and Engineering State Key Laboratory of Chemical Resource EngineeringCollege of Science Beijing University of Chemical Technology Beijing National Laboratory for Molecular Sciences Institute of Chemistry Chinese Academy of Sciences

In recent years, the sensor array has attracted much attention in the field of complex system analysis on the basis of its good selectivity and easy operation. many optical colorimetric sensor arrays are designed to analyze multi-target analytes due to the good sensitivity of optical signal. In this review, we introduce the targeting analytes, sensing mechanisms and data processing methods of the optical colorimetric sensor array based on optical probes(including organic molecular probes, polymer materials and nanomaterials). The research progress in the detection of metal ions, anions, toxic gases, organic compounds, biomolecules and living organisms(such as DNA, amino acids, proteins, microbes and cells) and actual sample mixtures are summarized *** review illustrates the types, application advantages and development prospects of the optical colorimetric sensor array to help broad readers to understand the research progress in the application of chemical sensor array.

关键词： sensor array optical colorimetric chemical analysis biological analysis

An approach to quality assessment for web service selection based on the analytic hierarchy process for cases of incomplete information

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Science China(Information Sciences) 2015年第12期58卷 75-88页

作者： GAO Cong ma JianFeng LIU ZhiQuan ma XinDi School of Computer Science and Technology Xidian University

Since web services intended for the same application environment tend to be functionally homogeneous, researchers have turned to their non-functional aspects in order to constructively compare web services and choose an appropriate one. In general, quality of service is very important to users. many schemes that consider quality assessment have been proposed for web service selection. With the increasing number of qualityrelated attributes, an effective quality assessment method needs satisfactory scalability. Schemes based on the analytic hierarchy process(AHP) meet this requirement. However, prevalent methods in this vein overlook the fact that the traditional AHP needs a complete judgment matrix. In practice, all the information needed to construct a judgment matrix is often unavailable for a variety of reasons, due to which certain judgments cannot be made. In this paper, for an incomplete judgment matrix, we propose an improved AHP approach to consistency verification and the subsequent ordering. Our method can deal with situations where information is insufficient,and inherits all the merits of the traditional AHP approach. A case study establishes the effectiveness of our proposed method.

关键词： incomplete information quality assessment analytic hierarchy process(AHP) web services qual ity of service selection

Gravitational wave search by time-scale-recursive denoising and matched filtering

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Science China(Physics,Mechanics & Astronomy) 2024年第12期67卷 166-182页

作者： Cunliang ma Chenyang ma Zhoujian Cao Mingzhen Jia School of Information Engineering Jiangxi University of Science and TechnologyGanzhou341000China Institute for Frontiers in Astronomy and Astrophysics Beijing Normal UniversityBeijing102206China School of Fundamental Physics and mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou310024China Jiangxi Provincial Key Laboratory of Multidimensional Intelligent Perception and Control Ganzhou341000China

In our previous work [Physical Review D,2024,109(4):043009],we introduced MSNRnet,a framework integrating deep learning and matched filtering methods for gravitational wave(GW) *** with end-to-end classification methods,MSNRnet is physically *** denoising models and astrophysical discrimination models corresponding to different parameter space were operated independently for the template prediction and *** the MSNRnet has a lot of computational *** this study,we propose a new framework for template prediction,which significantly improves our previous *** new framework consists of the recursive application of denoising models and waveform classification models,which solve the problem of computational *** waveform classification network categorizes the denoised output based on the signal's time *** enhance the denoising performance for long-time-scale data,we upgrade the denoising model by incorporating Transformer and ResNet ***,we introduce a novel training approach that allows for the simultaneous training of the denoising network and waveform classification network,eliminating the need for manual annotation of the waveform dataset required in our previous ***-data analysis results demonstrate that our new method decreases the false alarm rate by approximately 25%,boosts the detection rate by roughly 5%,and slashes the computational cost by around 90%.The new method holds potential for future application in online GW data processing.

关键词： gravitational wave matched filtering deep learning