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Historic and future Perspectives of Storm and Cyclone

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Advances in Atmospheric Sciences 2023年第3期40卷 447-463页

作者： Gang Fu Pengyuan LI Lijia CHEN Yongmao PENG Jing NI Department of Marine Meteorology Ocean-Atmosphere Interaction and Climate LaboratoryKey Laboratory of Physical OceanographyOcean University of ChinaQingdao 266100China Division of Oceanic Dynamics and Climate Pilot National Laboratory for Marine Science and Technology(Qingdao)Qingdao 266000China

In weather sciences,the two specific terms“storm”and“cyclone”frequently appear in literature and usually refer to the violent nature of a number of weather systems characterized by central low pressure,strong winds,large precipitation amounts in the form of rain,freezing rain,or snow,as well as thunder and lightning.But what is the connection between these two specific terms?In this paper,the historic evolutions of the terms“storm”and“cyclone”are reviewed from the perspective of weather science.The earliest recorded storms in world history are also briefly introduced.Then,the origin of the term“meteorological bomb”,which is the nickname of the“explosive cyclone”is introduced.Later,the various definitions of explosive cyclones given by several researchers are discussed.Also,the climatological features of explosive cyclones,as well as the future trends of explosive cyclones under global climate change,are discussed.

关键词： weather sciences storm and cyclone the origin of explosive cyclone climatological features global climate change future trends

Structure of the Potential Vorticity of an Explosive Cyclone over the Eastern Asian Region in Late November 2013

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Journal of Ocean University of China 2022年第2期21卷 253-263页

作者： PANG Huaji fu gang LU Chungu Qingdao Engineering Technology Research Center for Meteorological Disaster Prevention Qingdao Meteorological BureauQingdao 266003China Department of Marine Meteorology Laboratories of Physical OceanographyOcean-Atmosphere Interaction and ClimateOcean University of ChinaQingdao 266100China National Science Foundation ArlingtonVA 22230USA

An explosive extratropical cyclone(EC)over the Eastern Asian region that caused two shipwrecks is analyzed using ERA-Interim reanalysis data from the European Center for Medium-Range Weather Forecasts.Analyses of the evolution of the EC reveal that the positive potential vorticity(PV)at the upper-tropospheric level displays a hook-shaped structure during the mature period of the cyclone.The PV distribution forms a vertically coherent PV structure called a PV tower.The vertical distribution of the PV can induce and strengthen cyclonic circulation from the lower-to upper-levels of troposphere,which is an important deepening mechanism of explosive cyclone.The PV tower occurs approximately ten hours prior to the development of surface occlusion in the cyclone.The evolution of surface fronts closely follows the development of the horizontal upper-tropospheric PV.This tandem development is largely attributed to the ability of the positive upper-tropospheric PV and the PV tower to induce cyclonic circulation simultaneously.The kinematic wrap-up process of cyclonic circulation also accelerates the formation of warm occlusion.A conceptual model of the distributions of positive PV and potential temperature combining the perspectives of dynamic tropopause folding,PV tower,and atmospheric stability,including westward tilting and baroclinicity,is proposed.This model can illustrate the explosive deepening mechanism of ECs.The regions of convective instability and rainfall determined by this model are consistent with those identified from the actual observation.

关键词： extratropical cyclone rapidly deepening mechanism potential vorticity front evolution coupling of upper-and low-troposphere

A 38-Year Climatology of Explosive Cyclones over the Northern Hemisphere

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Advances in Atmospheric Sciences 2020年第2期37卷 143-159页

作者： Gang Fu Yawen SUN Jilin SUN Pengyuan LI Department of Marine Meteorology Ocean−Atmosphere Interaction and Climate LaboratoryKey Laboratory of Physical OceanographyOcean University of ChinaQingdao 266100China Division of Oceanic Dynamics and Climate Qingdao National Laboratory for Marine Science and TechnologyQingdao 266100China North China Sea Marine Forecasting Center Qingdao 266100China Shandong Provincial Key Laboratory of Marine Ecological Environment and Disaster Prevention and Mitigation Qingdao 266100China

Explosive cyclones(ECs)over two basins in the Northern Hemisphere(20°-90°N)from January 1979 to December2016 are investigated using ERA-Interim and Optimum Interpolation Sea Surface Temperature(OISST)data.The classical definition of an EC is modified considering not only the rapid drop of the central sea level pressure of the cyclone,but also the strong wind speed at the height of 10 m in which maximum wind speeds greater than 17.2 m s^-1are included.According to the locations of the northern Atlantic and northern Pacific,the whole Northern Hemisphere is divided into the"A region"(20°-90°N,90°W-90°E)and"P region"(20°-90°N,90°E-90°W).Over both the A and P regions,the climatological features of ECs,such as their spatial distribution,intensity,seasonal variation,interannual variation,and moving tracks,are documented.

关键词： explosive cyclone Atlantic basin Pacific basin Northern Hemisphere annual climatology seasonal climatology spatial distribution moving track

Digital Twin for Integration of Design-Manufacturing-Maintenance:An Overview

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Chinese Journal of Mechanical Engineering 2022年第4期35卷 1-20页

作者： Yang fu gang Zhu Mingliang Zhu fuzhen Xuan Key Laboratory of Pressure Systems and Safety Ministry of EducationSchool of Mechanical and Power EngineeringEast China University of Science and TechnologyShanghai 200237China

Traditional design,manufacturing and maintenance are run and managed independently under their own rules and regulations in an increasingly time-and-cost inefective manner.A unifed platform for efcient and intelligent designmanufacturing-maintenance of mechanical equipment and systems is highly needed in this rapidly digitized world.In this work,the defnition of digital twin and its research progress and associated challenges in the design,manufacturing and maintenance of engineering components and equipment were thoroughly reviewed.It is indicated that digital twin concept and associated technology provide a feasible solution for the integration of design-manufacturingmaintenance as it has behaved in the entire lifecycle of products.For this aim,a framework for information-physical combination,in which a more accurate design,a defect-free manufacturing,a more intelligent maintenance,and a more advanced sensing technology,is prospected.

关键词： Digital twin Design-manufacturing-maintenance integration Artifcial intelligence Deep learning Information fusion Cyber-physical systems

Effects of phase change material(PCM)-based nanocomposite additives on thermal decomposition and burning characteristic of high energy propellants containing RDX

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Defence Technology（防务技术） 2022年第4期18卷 557-566页

作者： En-fa fu Na Sun Zheng-gang Xiao Key Laboratory of Special Energy Materials Ministry of Education School of Chemical Engineering Nanjing University of Science and Technology

A kind of phase change material(PCM)-based nanocomposite was prepared and added into high energy propellants containing RDX as additives to investigate its effect on thermal decomposition and burning characteristic of high energy propellants.The effect of PCM-based nanocomposites on thermal decomposition of high energy propellants is investigated by TG/DSC-FTIR-MS technology.Due to the delayed protection effect(PCM-based nanocomposites can absorb lots of heat at the range of certain temperature when it undergoes structure change or phase transitions)of PCM-based nanocomposites under the thermal decomposition condition,the thermal stability of high energy propellants modified with PCMbased nanocomposites is improved.At the same time,the concentration of N2,NO2,H2O and CO_(2)is increased during thermal decomposition of high energy propellants whereas NO and CO is decreased.The burning gaseous products and burning characteristic of high energy propellants are studied by the combination of closed bomb test and Fourier transform infrared spectrum.The main burning gaseous products are N2,CO_(2),CO,H2O,CH4,etc.After the high energy propellant modified with PCM-based nanocomposites,the concentration of CH4is increased while CO,CO_(2) and H2O is decreased under the high-pressure burning condition.The progressivity factor of high energy propellants is increased by22.2%compared with the control sample while the maximum pressure is merely decreased 1.25%after the addition of the PCM-based nanocomposite,thus PCM-based nanocomposites can be used to adjust the burning process and improve the burning progressivity of high energy propellants.This study is expected to boost the practical application of PCM-based nanocomposite to the propellant formulation and effectively control the burning characteristic of high energy propellants.

关键词： Phase change material Propellants Nanocomposite Thermal decomposition Burning

The mechanism of hydrogen abstraction by high valence transition metal oxo compounds

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Journal of Energy Chemistry 2016年第6期25卷 1045-1050页

作者： Gang Fu Ruming Yuan Huilin Wan Xin Xu Department of Chemistry State Key Laboratory for Physical Chemistry of Solid Surfaces College of Chemistry & Chemical Engineering Xiamen University Department of Chemistry MOE Laboratory for Computational Physical Science Shanghai Key Laboratory of Molecular Catalysis and Innovative MaterialsFudan University

We present here a systematic theoretical study to explore the underlying mechanisms of the H abstraction reaction from methane. Various abstracting agents have been modeled, using oxygen radicals and a set of high valence metal oxo compounds. Our calculations demonstrate that although H abstraction from CH3-H by metal oxoes can be satisfactorily fitted into the Polanyi correlation on the basis of oxygen radicals, the mechanisms behind are significantly different. The frontier orbital analyses show that there are three electrons and three active orbitals (3e, 3o) involved in H abstraction by oxygen radicals; whereas an additional orbital of pi(M-O)* is involved in H abstraction by M = O, resulting in a (4e, 4o) interaction. In terms of valence bond state correlation diagram, we find that H abstraction by a metal oxo may benefit from the contribution of ionic resonance structures, which could compensate the penalty of opening the M-O pbond. We believe that these findings can help to design more effective catalysts for the activation of light alkanes. (C) 2016 Science Press and Dalian Institute of Chemical Physics, Chinese Academy of Sciences. Published by Elsevier B. V. and Science Press. All rights reserved.

关键词： C-H bond activation Polanyi relationship Oxygen radical Valence bond state correlation diagram DFT calculation

Aging properties and aging mechanism of activated waste rubber powder modified asphalt binder based on rheological properties and micro-characterization

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Frontiers of Structural and Civil Engineering 2023年第4期17卷 625-636页

作者： Peipei KONG gang XU Liuxu fu Xianhua CHEN Wei WEI School of Transportation Southeast UniversityNanjing 211189China School of Chemistry and Chemical Engineering Southeast UniversityNanjing 211189China

The research and development of high-performance pavement materials has been intensified owing to the demand for long-life pavements.This study is performed to develop a novel pavement material using waste rubber powder,waste lubricating by-product(LBP),and asphalt.Subsequently,the aging properties and aging mechanism of activated waste rubber powder modified asphalt(ARMA)are investigated based on its rheological properties and microcharacterization.The rheological results show that,compared with waste rubber powder modified asphalt(RMA),ARMA offers a higher aging resistance and a longer fatigue life.A comparison and analysis of the rheological aging parameters of ARMA and RMA show that LBP activation diminishes the aging sensitivity of ARMA.The microcharacterization result shows that the aging of ARMA may be caused by the fact that LBP-activated waste rubber powder is more reactive and can form a dense colloidal structure with asphalt.Therefore,the evaporation loss of asphalt light components by heat and the damage to the colloidal structure by oxygen during the aging process are impeded,and the thermal-oxidative aging resistance of ARMA is improved.

关键词： rubber powder modified asphalt aging mechanism rheological characterization

Analytic Mechanism for the Cumulative Effect of Wind Power Fluctuations from Single Wind Farm to Wind Farm Cluster

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CSEE Journal of Power and Energy Systems 2022年第5期8卷 1290-1301页

作者： gang Mu Fangze Wu Xiaoping Zhang Ziheng fu Bai Xiao Key Laboratory of Modern Power System Simulation and Control&Renewable Energy Technology Ministry of Education(Northeast Electric Power University)Jilin 132012China Department of Electronic Electrical and Systems EngineeringSchool of EngineeringUniversity of BirminghamBirmingham B152TTU.K

The use of wind power is rapidly growing worldwide as a means of reducing carbon emissions for the energy sector.China has the world’s largest wind power installation and multiple large-scale wind farm clusters,each comprising dozens of wind farms.For the planning and operation of the power system,it is important to understand the power fluctuation characteristics of wind farm clusters.Several studies demonstrate that the relative power fluctuation of a wind farm cluster is less than that of a single wind farm.Is this decreasing trend a random occurrence or does it have a regular pattern?This scientific question is addressed by investigating the mechanism of the cumulative effect of a wind farm cluster.In this study,a cumulative model is proposed by examining the spatiotemporal relationships of wind power variations and wind farm dispersion.Structural gain function and critical cumulative frequency are defined as the foundations to analytically describing the cumulative effect.By investigating the cumulative effect mechanism,the relationship between power fluctuation and spatiotemporal parameters of the wind farm cluster are revealed.The power fluctuation of a cluster can be predicted using the cumulative model even before it is completely built.The mechanism of the cumulative effect is validated on the basis of the data of two actual wind farm clusters.

关键词： Analytic mechanism cumulative effect evolution regularity wind farm cluster wind power fluctuation

Navigation jamming signal recognition based on long short-term memory neural networks

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Journal of Systems Engineering and Electronics 2022年第4期33卷 835-844页

作者： fu Dong LI Xiangjun MOU Weihua MA Ming OU gang College of Electronic Science and Technology National University of Defense TechnologyChangsha 410005China

This paper introduces the time-frequency analyzed long short-term memory(TF-LSTM) neural network method for jamming signal recognition over the Global Navigation Satellite System(GNSS) receiver. The method introduces the long shortterm memory(LSTM) neural network into the recognition algorithm and combines the time-frequency(TF) analysis for signal preprocessing. Five kinds of navigation jamming signals including white Gaussian noise(WGN), pulse jamming, sweep jamming, audio jamming, and spread spectrum jamming are used as input for training and recognition. Since the signal parameters and quantity are unknown in the actual scenario, this work builds a data set containing multiple kinds and parameters jamming to train the TF-LSTM. The performance of this method is evaluated by simulations and experiments. The method has higher recognition accuracy and better robustness than the existing methods, such as LSTM and the convolutional neural network(CNN).

关键词： satellite navigation jamming recognition time-frequency(TF)analysis long short-term memory(LSTM)