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A Regional Ensemble Forecast System for Stratiform Precipitation Events in Northern *** I:A Case Study

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Advances in Atmospheric Sciences 2012年第1期29卷 201-216页

作者： zhu jiangshan Fanyou KONG LEI Hengchi Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029 Graduate University of Chinese Academy of Sciences Beijing 100049 Center for Analysis and Prediction of Storms University of OklahomaUSA

A single-model, short-range, ensemble forecasting system （Institute of Atmospheric Physics, Regional Ensemble Forecast System, IAP REFS） with 15-km grid spacing, configured with multiple initial conditions, multiple lateral boundary conditions, and multiple physics parameterizations with 11 ensemble members, was developed using the Weather and Research Forecasting Model Advanced Research modeling system for prediction of stratiform precipitation events in northern China. This is the first part of a broader research project to develop a novel cloud-seeding operational system in a probabilistic framework. The ensemble perturbations were extracted from selected members of the National Center for Environmental Prediction Global Ensemble Forecasting System （NCEP GEFS） forecasts, and an inflation factor of two was applied to compensate for the lack of spread in the GEFS forecasts over the research region. Experiments on an actual stratiform precipitation case that occurred on 5-7 June 2009 in northern China were conducted to validate the ensemble system. The IAP REFS system had reasonably good performance in predicting the observed stratiform precipitation system. The perturbation inflation enlarged the ensemble spread and alleviated the underdispersion caused by parent forecasts. Centering the extracted perturbations on higher-resolution NCEP Global Forecast System forecasts resulted in less ensemble mean root-mean-square error and better accuracy in probabilistic quantitative precipitation forecasts （PQPF）. However, the perturbation inflation and recentering had less effect on near-surface-level variables compared to the mid-level variables, and its influence on PQPF resolution was limited as well.

关键词： short-range ensemble forecast rain enhancement operation probabilistic forecast

Impact of Soil Moisture Uncertainty on Summertime Short-range Ensemble Forecasts

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Advances in Atmospheric Sciences 2018年第7期35卷 839-852页

作者： jiangshan zhu Fanyou KONG Xiao-Ming HU Yan GUO Lingkun RAN Hengchi LEI Institute of Atmospheric Physics Chinese Academy of Sciences Center for Analysis and Prediction of Storms University of Oklahoma State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University

To investigate the impact of soil moisture uncertainty on summertime short-range ensemble forecasts（SREFs）, a fivemember SREF experiment with perturbed initial soil moisture（ISM） was performed over a northern China domain in summertime from July to August 2014. Five soil moisture analyses from three different operational/research centers were used as the ISM for the ensemble. The ISM perturbation produced notable ensemble spread in near-surface variables and atmospheric variables below 800 h Pa, and produced skillful ensemble-mean 24-h accumulated precipitation（APCP24） forecasts that outperformed any single ensemble member. Compared with a second SREF experiment with mixed microphysics parameterization options, the ISM-perturbed ensemble produced comparable ensemble spread in APCP24 forecasts, and had better Brier scores and resolution in probabilistic APCP24 forecasts for 10-mm, 25-mm and 50-mm thresholds. The ISM-perturbed ensemble produced obviously larger ensemble spread in near-surface variables. It was, however, still under-dispersed, indicating that perturbing ISM alone may not be adequate in representing all the uncertainty at the near-surface level, indicating further SREF studies are needed to better represent the uncertainties in land surface processes and their coupling with the atmosphere.

关键词： ensemble forecast soil moisture perturbation probabilistic quantitative precipitation forecast

Comparison of aircraft observations with ensemble forecast model results in terms of the microphysical characteristics of stratiform precipitation

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Atmospheric and Oceanic Science Letters 2020年第5期13卷 452-461页

作者： FU Yuan LEI Hengchi YANG Jiefan GUO Jiaxu zhu jiangshan Key Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina College of Earth and Planetary Science University of Chinese Academy of SciencesBeijingChina

The prediction of the particle number concentration and liquid/ice water content of cloud is significant for many aspects of atmospheric ***,given the uncertainties in the initial and boundary conditions and imperfections of microphysical schemes,the accurate prediction of these microphysical properties of cloud is still a big *** ensemble approach may be a viable way to reduce forecast *** this paper,a large-scale stratiform cloud precipitation process is studied by comparing results of a 10-member ensemble forecast model with aircraft observation *** means of the ensemble average,the prediction of bulk parameters such as liquid water content and ice water content can be improved in comparison with the control member,but the particle number concentrations are still one to two orders of magnitude less than those from *** of raindrop size spectra reveals a big distinction between observations and predictions for particles with a diameter less than 1000μm.

关键词： Aircraft observation ensemble forecast model particle number concentration liquid/ice water content

Analysis of the characteristics of gravity waves during a local rainstorm event in Foshan,China

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Atmospheric and Oceanic Science Letters 2020年第2期13卷 163-170页

作者： WANG Xiujuan LEI Hengchi FENG Liang zhu jiangshan LI Zhaoming JIANG Zhongbao Key Laboratory of Cloud-Precipitation Physics and Severe Storms of Chinese Academy of Sciences Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina College of Earth and Planetary Sciences University of Chinese Academy of SciencesBeijingChina Meteorological Observatory of Jilin Province Jilin Province Meteorological BureauChangchunChina Foshan Tornado Research Center Foshan Meteorological BureauFoshanChina Climate Center of Jilin Province Jilin Province Meteorological BureauChangchunChina

A detailed analysis of the dynamic frequency spectrum characteristics of gravity waves(GWs)during a local heavy rainfall event on 20–21 November 2016 in Foshan,China,is *** results of this analysis,which was based on high-precision microbarograph data,indicate that GWs played a key role in generating the *** GWs experienced two intermittent periods of amplitude enhancement and period *** largest amplitudes of the GWs were 80–160 Pa,with a corresponding period range of 140–270 min,which were approximately 4 h ahead of the *** severe storms appeared to affect the GWs by augmenting the wave amplitudes with center amplitudes of approximately 80–100 Pa and periods ranging between 210 and 270 min;in particular,the amplitudes increased to approximately 10 Pa for GWs with shorter periods(less than 36 min).The pre-existing large-amplitude GWs may be precursors to severe storms;that is,these GWs occurred approximately 4 h earlier than the time radars and satellites identified ***,these results indicate that large-amplitude GWs constitute a possible mechanism for severe-storm warning.

关键词： Gravity wave microbarograph dynamic characteristics short period long period amplitude

Comparison of different land-surface perturbation methods in short-range ensemble forecasts

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Atmospheric and Oceanic Science Letters 2021年第3期14卷 60-65页

作者： Zhibo Gao jiangshan zhu Yan Guo Xiaodong Yan Xiujuan Wang Huoqing Li Shuwen Li State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal UniversityBeijingChina Key Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of SciencesBeijingChina Jilin Province Technology Center for Meteorological Disaster Prevention ChangchunChina Institute of Desert Meteorology China Meteorological AdministrationUrumqiChina

In order to compare the sensitivity of short-range ensemble forecasts to different land-surface parameters in the South China region,three perturbation experiments related to the land surface model(LSM),initial soil moisture(ISM),and land–atmosphere coupling coefficient(LCC)were designed,and another control experiment driven by the Global Ensemble Forecast System(GEFS)was also *** ensemble members were initiated at 0000 UTC each day,and integrated for 24 h for a total of 40 days from the period 1 April to 10 May 2019 based on the Weather Research and Forecasting *** results showed that the perturbation experiment of the LSM(LSMPE)had the largest ensemble spread,as well as the lowest ensemble-mean root-mean-square error among the three sets of land-surface perturbed experiments,which indicated that it could represent more uncertainty and less *** ensemble spread of the perturbation experiment of the ISM(ISMPE)was generally less than that of LSMPE but greater than that of LCCPE(the perturbation experiment of the LCC).In particular,although the perturbation of the LCC could not produce greater spread,it had an effective influence on the intensity of ***,the ensemble spread of all the land-surface perturbed experiments was smaller than that of GEFSPE(the control experiment).Therefore,in future,land-surface perturbations and atmospheric perturbations should be combined in the design of ensemble forecasting systems to make the model represent more uncertainties.

关键词： Short-range ensemble forecast Land-surface parameter South china region

Comprehensive understanding on sources of high levels of fine particulate nitro-aromatic compounds at a coastal rural area in northern China

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Journal of Environmental Sciences 2024年第1期135卷 483-494页

作者： Yueru Jiang Xinfeng Wang Min Li Yiheng Liang Zhiyi Liu Jing Chen Tianyi Guan jiangshan Mu Yujiao zhu He Meng Yang Zhou Lan Yao Likun Xue Wenxing Wang Environment Research Institute Shandong UniversityQingdao 266237China Department of Environmental Systems Science Swiss Federal Institute of Technology ZurichZurich 8092Switzerland Department of Water Resources and Drinking Water Swiss Federal Institute of Aquatic Science and TechnologyDuebendorf 8600Switzerland Qingdao Eco-Environment Monitoring Center of Shandong Province Qingdao 266003China College of Oceanic and Atmospheric Sciences Ocean University of ChinaQingdao 266100China School of Environmental and Geographical Sciences Shanghai Normal UniversityShanghai 200234China

Nitro-aromatic compounds(NACs)are among the major components of brown carbon(BrC)in the atmosphere,causing negative impacts on regional climate,air quality,and ecological *** to the extensive origins,it is still a challenge to figure out the contributions and originating regions for different sources of atmospheric ***,field observations on fine particulate NACs were conducted at a coastal rural area in Qingdao,China in the winter of 2018 and *** mean total concentrations of fine particulate nitro-aromatic compounds were 125.0±89.5 and 27.7±21.1 ng/m^(3)in the winter of 2018 and 2019,*** the measured eleven NACs,nitrophenols and nitrocatechols were the most abundant *** characteristics and correlation analysis showed that humidity and anthropogenic primary emissions had significant influences on the NAC *** this study,two tracing methods of the improved spatial concentration weighted trajectory(SCWT)model and the receptor model of positive matrix factorization(PMF)were combined to comprehensively understand the origins of NACs in fine particles at coastal *** major sources were identified,including coal combustion,biomass burning,vehicle exhaust,and secondary ***,coal combustion was responsible for about half of the observed nitro-aromatic compounds,followed by biomass burning(~30%).The results by SCWT demonstrated that the coal combustion dominated NACs mainly originated from the Shandong peninsula and the areas to the north and southwest,while those dominated by biomass burning primarily came from local Qingdao and the areas to the west.

关键词： Nitro-aromatic compounds Fine particles Source apportionment Originating region Combustion activities

WAVELET-BASED FINE GRANULARITY SCALABLE VIDEO CODING

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Journal of Electronics(China) 2003年第1期20卷 38-44页

作者： Zhang jiangshan zhu Guangxi (Dept. of Electronics & Info. Eng., Huazhong University of Science & Technology, Wulian 430074) Dept. of Electronics & Info. Eng. Huazhong University of Science & Technology Wuhan 430074

This letter proposes an efficient wavelet-based Fine Granularity Scalable (FGS)coding scheme, where the base layer is encoded with a newly designed wavelet-based coder, and the enhancement layer is encoded with Progressive Fine Granularity Scalable (PFGS) *** algorithm involves multi-frame motion compensation, rate-distortion optimizing strategy with Lagrangian cost function and context-based adaptive arithmetic coding. In order to improve efficiency of the enhancement layer coding, an improved motion estimation scheme that uses both information from the base layer and the enhancement layer is also proposed in this letter. The wavelet-based coder significantly improves the coding efficiency of the base layer compared with MPEG-4 ASP (Advanced Simple Profile) and H.26L TML9. The PFGS coding is a significant improvement over MPEG-4 FGS coding at the enhancement layer. Experiments show that single layer coding efficiency gain of the proposed scheme is about 2.0-3.0dB and 0.3-1.0dB higher than that of MPEG-4 ASP and H.26L TML9, respectively. The overall coding efficiency gain of the proposed scheme is about 4.0-5.0dB higher than that of MPEG-4 FGS.

关键词： Wavelet-based coding Scalable coding FGS coding H.26L MPEG-4

A ROBUST ADAPTIVE VIDEO ENCODER BASED ON HUMAN VISUAL MODEL

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Journal of Electronics(China) 2003年第2期20卷 142-149页

作者： Yin Hao Zhang jiangshan zhu Yaoting zhu Guangxi (Dept. of Electronics & Info. Eng., Huazhong University of Sci. & Tech., Wuhan 430074) Dept. of Electronics & Info. Eng. Huazhong University of Sci. & Tech. Wuhan430074

A Robust Adaptive Video Encoder (RAVE) based on human visual model is proposed. The encoder combines the best features of Fine Granularity Scalable (FGS) coding, framedropping coding, video redundancy coding, and human visual model. According to packet loss and available bandwidth of the network, the encoder adjust the output bit rate by jointly adapting quantization step-size instructed by human visual model, rate shaping, and periodically inserting key frame. The proposed encoder is implemented based on MPEG-4 encoder and is compared with the case of a conventional FGS algorithm. It is shown that RAVE is a very efficient robust video encoder that provides improved visual quality for the receiver and consumes equal or less network resource. Results are confirmed by subjective tests and simulation tests.

关键词： FGS coding Redundancy coding Human visual model Rate shaping MPEG 4

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柏拉图与涂尔干“社会分工论”比较探析

北京印刷学院学报 2018年第6期26卷 86-89页

作者：朱江山贵州师范大学贵阳550001

社会分工论常被视为解决社会冲突问题的有效途径之一。西方社会分工论的源起离不开柏拉图和涂尔干两位思想家。前者是西方最早提出社会分工问题的思想家,而后者则是社会分工论研究的集大成者。本文立足于两位思想家的代表作《理想国》... 详细信息

社会分工论常被视为解决社会冲突问题的有效途径之一。西方社会分工论的源起离不开柏拉图和涂尔干两位思想家。前者是西方最早提出社会分工问题的思想家,而后者则是社会分工论研究的集大成者。本文立足于两位思想家的代表作《理想国》和《社会分工论》,从分工原因、分工结果以及非正常状态的分工三个层面,比较分析两位思想家的思想分歧及其理论意义。

关键词：社会分工论柏拉图涂尔干