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Advances in Atmospheric Sciences 2015年第4期32卷 565-576页

作者： LUO Xia FEI Jianfang HUANG Xiaogang cheng xiaoping DING Juli HE Yiqiang College of Meteorology and Oceanography PLA University of Science and Technology Beijing Aerospace Control Center

Based on best track data of tropical cyclones（TCs） from the Japan Meteorological Agency, the characteristics of suddenly reversed TCs（SRTCs）, which have turning angles usually approaching 180°, are statistically analyzed from 1949 to 2011 over the western North Pacific Ocean. The typical large-scale circulation patterns of SRTCs are investigated using reanalysis data and dynamical composite analysis. Results show that turnings mainly occur in low latitudes between 10°N and 20°N,and mainly west of 135°E. The majority of SRTCs reach their peak intensity at, or slightly before, the turning time and subsequently decrease at some variable rate. Specifically, SRTCs are divided into four types, each containing two groups（*** groups in total） in terms of the moving-direction changes. The moving speed of all SRTC types except the south–north type decreases to its lowest during the 24 h, corresponding to a significant reduction in the primary steering *** to the analysis of the 13 typical flow patterns found in this study, we suggest that sudden track changes are caused by the reversal steering flow. The original balance of the background flow patterns are broken up by new systems, e.g. binary TCs or dispersion-induced anticyclones. Additionally, sudden track changes are often due to double ridge variations of the subtropical high or weakened/strengthened high pressure in the east and west, respectively.

关键词： tropical cyclone suddenly reversed turning statistical analysis steering flow

Asymmetric Distribution of Convection in Tropical Cyclones over the Western North Pacific Ocean

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Advances in Atmospheric Sciences 2016年第11期33卷 1306-1321页

作者： Lu YANG Jianfang FEI Xiaogang HUANG xiaoping cheng Xiangrong YANG Juli DING Wenli SHI Institute of Meteorology and Oceanography PLA University of Science and Technology

Forecasts of the intensity and quantitative precipitation of tropical cyclones（TCs） are generally inaccurate, because the strength and structure of a TC show a complicated spatiotemporal pattern and are affected by various factors. Among these, asymmetric convection plays an important role. This study investigates the asymmetric distribution of convection in TCs over the western North Pacific during the period 2005–2012, based on data obtained from the Feng Yun 2（FY2）geostationary satellite. The asymmetric distributions of the incidence, intensity and morphology of convections are *** show that the PDFs of the convection occurrence curve to the azimuth are sinusoidal. The rear-left quadrant relative to TC motion shows the highest occurrence rate of convection, while the front-right quadrant has the lowest. In terms of intensity, weak convections are favored in the front-left of a TC at large distances, whereas strong convections are more likely to appear to the rear-right of a TC within a 300 km range. More than 70% of all MCSs examined here are elongated systems, and meso-β enlongated convective systems（MβECSs） are the most dominant type observed in the outer region of a TC. Smaller MCSs tend to be more concentrated near the center of a TC. While semi-circular MCSs [MβCCSs, MCCs（mesoscale convective complexes）] show a high incidence rate to the rear of a TC, elongated MCSs [MβECSs, PECSs（persistent elongated convective systems）] are more likely to appear in the rear-right quadrant of a TC within a range of 400 km.

关键词： convection Tropical convective asymmetric tropical mesoscale elongated typhoon likely storm

The four dimensional variational data assimilation with multiple regularization parameters as a weak constraint(Tikh-4D-Var) and its preliminary application on typhoon initialization

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Science China Earth Sciences 2014年第7期57卷 2690-2701页

作者： ZHONG Jian FEI JianFang cheng xiaoping HUANG XiaoGang China Satellite Maritime Tracking and Control Department Institute of Meteorology and Oceanography PLA University of Science and Technology

Traditional variational data assimilation （VDA） with only one regularization parameter constraint cannot produce optimal error tuning for all observations. In this paper, a new data assimilation method of ＂four dimensional variational data assimilation （4D-Var） with multiple regularization parameters as a weak constraint （Tikh-4D-Var）＂ is proposed by imposing different reg- ularization parameters for different observations. Meanwhile, a new multiple regularization parameters selection method, which is suitable for actual high-dimensional data assimilation system, is proposed based on the posterior information of 4D-Var system. Compared with the traditional single regularization parameter selection method, computation of the proposed multiple regularization parameters selection method is smaller. Based on WRF3.3.1 4D-Vat data assimilation system, initiali- zation and simulation of typhoon Chaba （2010） with the new Tikh-4D-Var method are compared with its counterpart 4D-Var to demonstrate the effectiveness of the new method. Results show that the new Tikh-4D-Var method can accelerate the con vergence with less iterations. Moreover, compared with 4D-Var method, the typhoon track, intensity （including center surface pressure and maximum wind speed） and structure prediction are obviously improved with Tikh-4D-Var method for 72-h pre- diction. In addition, the accuracy of the observation error variances can be reflected by the multiple regularization parameters.

关键词： multiple regularization parameters 4D-Var typhoon initialization

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Direct/indirect effects of aerosols and their separate contributions to Typhoon Lupit(2009):Eyewall versus peripheral rainbands

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Science China Earth Sciences 2021年第1期64卷 2113-2128页

作者： Zhichao LIANG Juli DING Jianfang FEI xiaoping cheng Xiaogang HUANG College of Meteorology and Oceanography National University of Defense TechnologyNanjing211101China PLA Troop 96746 Korla841000China

As a typhoon approaches the continent,the position where anthropogenic aerosols penetrate,the convection competition between the eyewall and peripheral rainbands,and the separate contributions of direct aerosol-radiation interactions(ARI)and indirect aerosol-cloud interactions(ACI),yield uncertainties in the convection intensification area and hence the typhoon *** Lupit(2009)was simulated using the Weather Research and Forecasting Model with Chemistry(WRF-Chem)to investigate and isolate the direct and indirect effects of aerosols on the intensity,convection,and precipitation of the *** simulations(CTL,CLEAN,and CTLARIOFF)were designed,representing a polluted case(CTL,considering the ingestion of anthropogenic aerosols with ARI and ACI),a clean maritime case(CLEAN,mainly with sea salt aerosols),and a polluted case without aerosol radiative forcing(CTLARIOFF,as per CTL but without ARI).The results showed that anthropogenic aerosols could penetrate into both the peripheral rainbands and the eyewall when the typhoon was approaching the Asian *** to the representation of the real aerosol scenario,the simulated typhoon intensity weakened and was closer to observed values in the CTL *** ARI dominated over ACI with the opposite ***,the ACI mainly enhanced the formation of ice-phase hydrometeors within the upper level of the eyewall with more freezing latent heat releases,leading to an invigoration of eyewall *** excess ice-phase particles melted after they descended into the warm layer below the 0°C level,which accelerated the accretion of cloud droplets by raindrops(Pcacr)and hence the mixed phase precipitation process in the *** dynamic feedback induced by the ACI enhanced the boundary layer inflow and the upper layer outflow,supporting the maintenance of strong eyewall convection and intensification of the ***,the ARI heated the distant periphery low-level atmosphere at an

关键词： Aerosol Tropical cyclone Eyewall Peripheral rainbands WRF-Chem

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A regional simulation study on dispersion of nuclear pollution from the damaged Fukushima Nuclear Power Plant

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Science China Earth Sciences 2014年第2期57卷 1513-1524页

作者： FEI JianFang WANG PengFei cheng xiaoping HUANG XiaoGang WANG YiBai College of Meteorology and Oceanography PLA University of Science and Technology Dalian Naval Academy 61741 Troops of PLA

A nuclear accident involving the leaking of radioactive pollutants occurred at the Fukushima Nuclear Power Plant in Japan, following an earthquake and subsequent tsunami on March 11,2011. Using official Japanese data on pollutant emissions during the accident, this study simulates the dispersion of nuclear pollutants. The source term of the nuclear leakage of radioactive material is designed using PM2.5 as the tracer of radioactive pollutants, and the study considers dry and wet deposition processes. A coupled-model system is constructed from the air-quality model Models-3/CMAQ and the Weather Research and Forecasting atmospheric model. The transport path and distribution of radioactive pollutants over long and short distances are simulated with different model horizontal resolutions of 30 and 4 km respectively. The long-distance simulation shows that, following the Fukushima nuclear accident, under the effect of westerly winds, radioactive pollutants are transported generally towards the eastern Pacific and reach the American continent after 5 days, but their concentration is only about 10-7 times the concentration near the Fukushima Nuclear Power Plant. The time required for pollutants to reach the United States is basically consistent with measurements made in California on March 18. Because the upper westerly wind is faster than the lower westerly wind, the distribution of pollutants tilts eastward in terms of its vertical structure. The short-distance （local） highresolution simulation indicates that strong winds and precipitation associated with a cyclone can accelerate the deposition, dif- fusion and transport of pollutions, and local cyclonic circulation can change the transport path of pollutants, even resulting in repeated effects of pollution in some areas. Pollutants disperse to southeastern Honshu, Japan, on March 14, 2011, agreeing well with the timing of local observations of increases in the absorbed dose rate. Results also show that radioactive pollu

关键词： radioactive pollutant Fukushima dispersion and transport numerical simulation

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Lion pride optimizer:An optimization algorithm inspired by lion pride behavior

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Science China(Information Sciences) 2012年第10期55卷 2369-2389页

作者： WANG Bo,JIN xiaoping & cheng Bo State Key Laboratory of Automotive Safety and Energy,Tsinghua University,Beijing 100084,China 1. State Key Laboratory of Automotive Safety and Energy Tsinghua University Beijing 100084 China

In this paper,we report a novel optimization algorithm,lion pride optimizer(LPO),which is inspired by lion pride *** framework is mainly based on lion prides’ evolution process and group living *** a lion pride,brutal competition of individuals happens among male lions both within and among prides;on the other hand,each member plays an important role in the persistence of a lion *** on this framework,concepts from lion prides behavior,e.g.,the strongest males occupy nearly all mating resources,and if a new cohort of males is able to take over a pride,they will seek to kill young cubs sired by their predecessors,are employed metaphorically to design optimum searching strategies for solving continuous optimization *** the studies of the algorithm property,it is found that the LPO algorithm is not sensitive to most parameters,which shows the robustness of the algorithm and the parameters are not *** tendency of the algorithm is not *** is found that the pride update strategy and brutal competition of individuals are two main factors that contribute to the performance of *** to the test results on 23 famous benchmark functions,the LPO algorithm has better performance than the other seven state-of-the-art algorithms on both unimodal and multimodal benchmark functions;in the test of high-dimensional multimodal problems,LPO outperforms the other five algorithms on all benchmark functions.

关键词： animal behavior evolutionary algorithm lion pride optimization swarm intelligence

ELIMINATING CROP SHADOWS IN VIDEO SEQUENCES BY PROBABLE LEARNING PIXEL CLASSIFICATION

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ELIMINATING CROP SHADOWS IN VIDEO SEQUENCES BY PROBABLE LEAR...

从清净心到平常心:论唐宋文化转型中的禅宗与文人心态

第一届国际计算机与计算技术在农业中的应用研讨会

作者： Tanghai Liu xiaoping cheng Faculty of Computer and Information Science Southwest University

Shadows have been one of the most serious problems for vegetation segmetalion,espescially under conditions of natural random airflow and human or vehicle disturbance.A video sequence processing method has developed in this paper to identify and eliminate crop *** method comprises pixel models and algorithms explained in a probable learning *** maximization（EM） for mixture models is established and an incremental EM method is *** method performs a probable reasoning unsupervised classification of pixels for real-time *** results show that the method is quite robust and can successfully remove shadows under natural lighting conditions.

关键词： probable learning shadows vegetation segmentation video processing

来源： cnki会议评论

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中州学刊 2021年第7期 151-157页

作者：程小平对外经济贸易大学中文学院北京100029

唐宋文人心态的转化是唐宋文化转型的重要一环,它由一系列复杂的内外因素合力驱动,其中一个重要方面就是禅宗思想对文人心态的影响与重构。为追求心灵彻底的自由解脱,王维皈依佛教禅宗;北宗禅清净心体悟使他的心灵摆脱世俗各种烦恼的干... 详细信息

唐宋文人心态的转化是唐宋文化转型的重要一环,它由一系列复杂的内外因素合力驱动,其中一个重要方面就是禅宗思想对文人心态的影响与重构。为追求心灵彻底的自由解脱,王维皈依佛教禅宗;北宗禅清净心体悟使他的心灵摆脱世俗各种烦恼的干扰,这实质上是对陶潜所追求的自由心的重构。清净心固然能使人摆脱世俗烦恼的困扰,但这种理想境界终究脱离日常生活太远。白居易、苏轼等人意识到清净心的困窘,他们从解脱日常烦恼的初衷出发,接受了南宗禅的平常心,将目光从理想的清静世界拉回平庸的日常生活,这实质上也是对理想清净心的重构。从自由心到清净心,再到平常心,禅宗在不断追求转化中重构了唐宋文人心态。这种转化体现在诗文中,就是从王维诗歌对理想清静之境的抒写衍变为白居易、苏轼诗文中闲适畅达心态的展露。文人心态从清净心到平常心的转化,显示了唐宋文化转型复杂形态中理想情怀被务实理性所取代的那一面相。

关键词：禅宗清净心平常心王维白居易苏轼

Development of an Integrated Vertical-Slantwise Convective Parameterization Scheme and Its Associated Numerical Experiments

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Acta meteorologica Sinica 2011年第4期25卷 405-418页

作者：费建芳伍荣生黄小刚王元程小平 Institute of Meteorology PLA University of Science & Technology Institute of Atmospheric Sciences Nanjing University

An integrated vertical-slantwise convective parameterization scheme, based on the vertical Kuo-Anthes and the slantwise Nordeng convective parameterization schemes, is introduced into the MM5 model. By employing the MM5 model with the proposed scheme, numerical simulations of a snowstorm event that occurred over southern China on 28-29 January 2008 and of Typhoon Haitang （2005） are conducted. The results indicate that during the snowstorm event, the atmosphere was convectively stable in the vertical direction but with conditional symmetric instability （CSI） in the lower troposphere, and when the area of CSI developed and extended to upper levels, strong rising motion occurred and triggered the release of large amount of energy, producing enhanced convective precipitation with the total precipitation much closer to the observation. The development and strengthening of CSI corresponded to changes in the intensity of snowfall, convergence, and ascending motions of air, revealing that CSI was responsible for the initiation and growth of the snowstorm. The results from a 72-h explicit simulation of Typhoon Haitang indicate that CSI occurred mainly at lower levels with a well-defined spiral structure, and it tended to have a larger impact on the intensity of typhoon than on its track. The minimum pressure at the typhoon center for the 72-h runs with the integrated vertical-slantwise convective parameterization scheme was on average 3 hPa （maximum 8 hPa） lower than that from the runs with only the vertical cumulus parameterization scheme. Introducing the influence of CSI into the model has improved the warm core structure at the middle and upper levels of the typhoon, with stronger and persistent upward motions causing increased precipitation, and the latent heat released through convection in turn made the typhoon develop further.

关键词： snowstorm typhoon conditional symmetric instability (CSI) the integrated vertical-slantwise convective parameterization scheme numerical simulation

在“政治”与“文化”之间──对当代西方文论一种特点的描述

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外国文学研究 2002年第1期24卷 20-24页

作者：程小平北京师范大学中文系 100875

本文通过回顾西方自 6 0年代以来主要几家文论的大致特征 ,发现它们均具有极鲜明的“政治”与“文化”之特征 ,而且 ,它们常常复杂地交错在一起。这在一定程度上表明两者之间存在一种互文性。文章认为。

关键词：西方文论当代互文性文章存在描述政治年代