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Hybrid Methods for Computing the Streamfunction and Velocity Potential for Complex Flow Fields over Mesoscale Domains

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Advances in Atmospheric Sciences 2022年第9期39卷 1417-1431页

作者： Jie CAO Qin XU Haishan CHEN Shuping MA Key Laboratory of Meteorological Disaster(KLME) Ministry of Education&Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing 210044China Cooperative Institute for Mesoscale Meteorological Studies(CIMMS) University of OklahomaNorman 73072OklahomaUSA NOAA/OAR/National Severe Storms Laboratory Norman 73069OklahomaUSA Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China

Three types of previously used numerical methods are revisited for computing the streamfunctionψand velocity potentialχfrom the horizontal velocity v in limited domains.The first type,called the SOR-based method,uses a classical successive over-relaxation(SOR)scheme to computeψ(orχ)first with an arbitrary boundary condition(BC)and thenχ(orψ)with the BC derived from v.The second type,called the spectral method,uses spectral formulations to construct the inner part of(ψ,χ)-the inversion of(vorticity,divergence)with a homogeneous BC,and then the remaining harmonic part of(ψ,χ)with BCs from v.The third type,called the integral method,uses integral formulas to compute the internally induced(ψ,χ)-the inversion of domain-internal(vorticity,divergence)using the free-space Greenꞌs function without BCs and then the remaining harmonicψ(orχ)with BCs from v minus the internally-induced part.Although these methods have previously been successfully applied to flows in large-scale and synoptic-scale domains,their accuracy is compromised when applied to complex flows over mesoscale domains,as shown in this paper.To resolve this problem,two hybrid approaches,the integral-SOR method and the integral-spectral method,are developed by combining the first step of the integral method with the second step adopted from the SOR-based and spectral methods,respectively.Upon testing these methods on real-case complex flows,the integral-SOR method is significantly more accurate than the integral-spectral method,noting that the latter is still generally more accurate than the three previously-used methods.The integral-SOR method is recommended for future applications and diagnostic studies of complex flows.

关键词： streamfunction and velocity potential complex flow fields successive over-relaxation method mesoscale study

Characteristics for the sources and sinks of gravity waves in an orographic heavy snowfall event

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Frontiers of Earth Science 2023年第2期17卷 604-619页

作者： Shuping MA Lingkun RAN Jie CAO Baofeng JIAO Kuo ZHOU Key Laboratory of Cloud–Precipitation Physics and Severe Storms Institute of Atmospheric Physics(LACS)Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Cooperative Institute for Mesoscale Meteorological Studies University of OklahomaNorman OK 73072USA Key Laboratory of Meteorological Disaster(KLME) Ministry of Education&Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing 210044China

The characteristics of the mesoscale gravity waves during a snowfall event on November 30,2018 over the Ili Valley and the northern slope of the Tianshan Mountains are analyzed based on the Weather Research and Forecasting model simulation.The vertical distribution of Ro is similar to that of the residual of the nonlinear balance equation(△NBE),with their high-value areas located over the leeward slope and the fluctuations extending upwardly with time,indicating the characteristics of strong ageostrophy and non-equilibrium of atmospheric motions.In addition,the Ro and(△NBE)are first developed in the lower layers over the leeward slope,revealing that the generation of the gravity waves is closely related to the topography.Thus,the topographic uplifting greatly affects this snowfall,and the ageostrophic motion in the whole troposphere and the lower stratosphere,as well as the unbalanced motions between convergence and divergence over the peak and the leeward slope are conductive to the development of the inertia-gravity waves.In terms of the horizontal scale of the gravity waves,the Barnes’bandpass filter is applied to separate the mesoscale waves and the synoptic-scale basic flow.The vertical distributions of the vorticity and divergence perturbations have a phase difference ofπ/2,indicating the polarization state of gravity waves.The analyses on the sources and sinks of gravity waves by the non-hydrostatic wave equation show that the main forcing term for orographic gravity waves is the second-order nonlinear term,whose magnitude mainly depends on the nonlinear thermal forcing.This term is mainly related to the vertical transport of potential temperature perturbations.During the snowfall,the potential temperature perturbations are mainly caused by the topographic relief and the release of condensation latent heat.Therefore,the gravity waves in this snowfall are caused by the topographic forcing and condensation latent heating.

关键词： gravity wave Fourier transform nonlinear balance equation non-hydrostatic wave equation

Significant concurrent decrease in PM_(2.5) and NO_(2) concentrations in China during COVID-19 epidemic

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Journal of Environmental Sciences 2021年第1期33卷 346-353页

作者： Biiuu Chu shuping Zhang Jun Liu Qingxin ma Hong He State Key Joint Laboratory of Environment Simulation and Pollution Control Research Center for Eco-Enuironmental SciencesChinese Academy of SciencesBeijing 100085China Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China

The strict control measures and social lockdowns initiated to combat COVID-19 epidemic have had a notable impact on air pollutant concentrations.According to observation data obtained from the China National Environmental Monitoring Center,compared to levels in 2019,the average concentration of NO_(2) in early 2020 during COVID-19 epidemic has decreased by 53%,50%,and 30%in Wuhan city,Hubei Province(Wuhan excluded),and China(Hubei excluded),respectively.Simultaneously,PM_(2.5) concentration has decreased by 35%,29%,and 19%in Wuhan,Hubei(Wuhan excluded),and China(Hubei excluded),respectively.Less significant declines have also been found for SO_(2) and CO concentrations.We also analyzed the temporal variation and spatial distribution of air pollutant concentrations in China during COVID-19 epidemic.The decreases in PM_(2.5) and NO_(2) concentrations showed relatively consistent temporal variation and spatial distribution.These results support control of NO x to further reduce PM_(2.5) pollution in China.The concurrent decrease in NOx and PM_(2.5) concentrations resulted in an increase of O3 concentrations across China during COVID-19 epidemic,indicating that coordinated control of other pollutants is needed.

关键词： Covid-19 epidemic Air quality Temporal variation and spatial distribution Coordinated control PM_(2.5) O3

Characteristics of diurnal variations of warm-season precipitation over Xinjiang Province in China

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Atmospheric and Oceanic Science Letters 2022年第2期15卷 13-18页

作者： Jie Cao Shuping MA Weihua Yuan Zhiyan Wu Key Laboratory of Meteorological Disaster(KLME) Ministry of Education and Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters (CIC-FEMD)Nanjing University of Information Science and TechnologyNanjingChina Institute of Atmospheric Physics Chinese Academy of SciencesBeijingChina Cooperative Institute for Mesoscale Meteorological Studies University of OklahomaOklahomaUSA University of Chinese Academy of Sciences BeijingChina Key Laboratory of South China Sea Meteorological Disaster Prevention HaikouChina

降水日变化受大气热力,动力过程以及复杂地形影响,演变特征复杂且区域差异显著.本文采用中国气象局发布的中国地面与CMORPH融合逐小时降水产品(2008–2019年),分析了新疆暖季降水日变化特征.研究结果表明:(1)新疆大部分地区降水主峰值... 详细信息

降水日变化受大气热力,动力过程以及复杂地形影响,演变特征复杂且区域差异显著.本文采用中国气象局发布的中国地面与CMORPH融合逐小时降水产品(2008–2019年),分析了新疆暖季降水日变化特征.研究结果表明:(1)新疆大部分地区降水主峰值发生在清晨;(2)持续时间超过三小时的降水事件是新疆地区主要降水事件,贡献了南疆和北疆一半以上的降水量;(3)在新疆中部(天山地区),暖季降水日变化峰值主要由持续时间超过7小时的降水事件贡献.

关键词：降水日变化不同持续时间降水事件区域差异干旱半干旱地区

Robust Admissible Consensus of Discrete-time Singular Multiagent Systems Using Sliding Mode Approach

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Robust Admissible Consensus of Discrete-time Singular Multia...

Robust stability and H-infinity control for uncertain discrete-time markovian jump singular systems

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作者： Min Li Shuping MA School of Electrical Engineering and Automation Qilu University of Technology (Shandong Academy Sciences) School of mathematics Shandong University

The robust admissible consensus problem of uncertain discrete-time singular multiagent systems（UDSmaSs） is addressed by sliding mode approach. With a leader-follower communication network, linear sliding manifolds and linear sliding mode control laws of error states of neighbor agents are designed to achieve simultaneously the reachability of sliding manifolds and the generalized quadratical stability of the sliding mode dynamics. The distributed admissible consensus control law is based on the sliding mode control laws of error states of neighbor agents and Laplacian matrix. A numerical example is provided to show the effectiveness of the proposed theories.

关键词： Robust admissible consensus discrete-time multiagent singular systems Distributed admissible consensus control law

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控制理论与应用（英文版） 2008年第2期6卷 133-140页

作者： Shuping MA Chenghui ZHANG Xinzhi LIU School of mathematics and System Science Shandong University Jinan Shandong 250100 China School of Computer Science and Technology Shandong University Jinan Shandong 250061 China School of Control and Engineering Shandong University Jinan Shandong 250061 China Department of Applied mathematics University of Waterloo Waterloo Ontario N2L 3G1 Canada

The robust stability and stabilization, and H-infinity control problems for discrete-time markovian jump singular systems with parameter uncertainties are discussed. Based on the restricted system equivalent （r.s.e.） transformation and by introducing new state vectors, the singular system is transformed into a discrete-time markovian jump standard linear system, and the linear matrix inequality （LMI） conditions for the discrete-time markovian jump singular systems to be regular, causal, stochastically stable, and stochastically stable with 7- disturbance attenuation are obtained, respectively. With these conditions, the robust state feedback stochastic stabilization problem and H-infinity control problem are solved, and the LMI conditions are obtained. A numerical example illustrates the effectiveness of the method given in the oaoer.

关键词： Discrete-time singular system markovian jump system Robust stability and stabilization H-infinitycontrol Linear matrix inequality（LMI）

Precise Synthesis of Organic Heterostructures via the Synergy Approach of Polymorphism and Cocrystal Engineering for Optical Applications

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Chinese Journal of Chemistry 2022年第10期40卷 1149-1155页

作者： Huiling Yin Yingxin ma Hongtao Lin Shuhai Chen Ziyan Zhou shuping Zhuo Xuedong Wang School of Chemistry and Chemical Engineering Shandong University of TechnologyZiboShandong 255000China Jiangsu Key Laboratory for Carbon-Based Functional materials&Devices Institute of Functional Nano&Soft Materials(FUNSOM)Soochow UniversitySuzhouJiangsu 215123China

Organic heterostructures that can integrate the physiochemical properties of two or more substances have atracted widespread attention in the field of optoelectronics.However,the epitaxial growth process between different organic material molecules is unpredictable,and the precise synthesis of organic heterostructures is stll particularly challenging.Herein,through the synergy approach of polymorphism and cocrystal engineering,a series of organic branched heterostructures have been successfully prepared.Interestingly,by simply adjusting the solvent ratio,different crystalline phases of perylene microplates can be epitaxilly grown on the perylene-OFN cocrystal microwires,which provides a feasible approach for the preparation of organic heterostructures.Meanwhile,these as-prepared organic branched heterostructures can realize multi-channel and multi-color emission,and act as optical logic gates,which promotes the multifunctional integrated optoelectronics.

关键词： Organic semiconductor molecules Polymorphism Synthesis design Epitaxial growth Organic photonics

Evolutionary selection for regression test cases based on diversity

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Frontiers of Computer Science 2021年第2期15卷 201-203页

作者： Baoying ma Li WAN Nianmin YAO shuping FAN Yan ZHANG School of Health management Mudanjiang Medical UniversityMudanjiang157011China Department of intelligence and Computing Tianjin UniversityTianjin300350China School of Computer Science and Technology Dalian University of TechnologyDalian116024China School of Computer and Information Technology Mudanjiang Normal UniversityMudanjiang157011China

1 Introduction Regression testing refers to retest code after modification to ensure that changes will not introduce new faults or cause faults in other lines of code[1].Regression test selection(RTS)is one of the predominant techniques.It identifies test cases that are relevant to test recent changes in an application and seeks to reduce the number of test suite while preserving the capability to reveal faults[2].

关键词： preserving predominant changes

Admissible Tracking and Containment Consensualization of Multi-agent Singular Systems

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Admissible Tracking and Containment Consensualization of Mul...