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Research and Operational Development of Numerical Weather Prediction in China

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Journal of Meteorological Research 2020年第4期34卷 675-698页

作者： Xueshun SHEN Jianjie WANG Zechun LI dehui chen Jiandong GONG National Meteorological Center China Meteorological AdministrationBeijing 100081 Numerical Weather Prediction Center of the China Meteorological Administration Beijing 100081 State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081

Numerical weather prediction(NWP) is a core technology in weather forecast and disaster mitigation. China’s NWP research and operational applications have been attached great importance by the meteorological *** achievements have been made in the theories, methods, and NWP model development in China, which are of certain international impacts. In this paper, the scientific and technological progress of NWP in China since1949 is summarized. The current status and recent progress of the domestically developed NWP system-GRAPES(Global/Regional Assimilation and Pr Ediction System) are presented. Through independent research and development in the past 10 years, the operational GRAPES system has been established, which includes both regional and global deterministic and ensemble prediction models, with resolutions of 3-10 km for regional and 25-50 km for global forecasts. Major improvements include establishment of a new non-hydrostatic dynamic core, setup of four-dimensional variational data assimilation, and development of associated satellite application. As members of the GRAPES system, prediction models for atmospheric chemistry and air pollution, tropical cyclones, and ocean waves have also been developed and put into operational use. The GRAPES system has been an important milestone in NWP science and technology in China.

关键词： numerical weather prediction(NWP) Global/Regional Assimilation and Pr Ediction System(GRAPES) semi-implicit semi-Lagrangian grid-point model physical process four-dimensional variational assimilation satellite data assimilation

Analysis and discussion of a dead-zone protection mal-operation case in Brazil

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Journal of Modern Power Systems and Clean Energy 2014年第1期2卷 87-91页

作者： dehui chen Yi XIA Wei LIU Salvatore MANTUANO NARI Technology Co. LTDNanjing 210003China State Grid Brazil Holding S.A. Rio de Janeiro 20071-004Brazil

A mal-operation case of busbar protection caused by a dead-zone protection abnormality in the Brazilian Midwest Grid on September 19th,2012,is briefly *** operation process of pilot distance,automatic re-closure,busbar differential and dead-zone protection,and the emphasis on the logic scheme of dead-zone protection are *** time delay between the breaker’s main pole and auxiliary contact during re-closure was the main cause in this case,and a defect in the logic allowed it to *** differences in dead-zone protection logic between Brazil and China are discussed.A test platform was constructed in the laboratory,and a site simulated experiment was also *** causes are suggested and test activities are carried out to verify *** show the values of practical engineering approaches to the *** also contributed to avoiding future mal-operations and strengthening the reliability of the protection system,and thus of the power supply in Brazil.

关键词： Brazilian power system Power system Relay protection device Dead-zone protection

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基于KPCA降维分析的特高拱坝监测模型

人民长江 2024年第10期55卷 246-254页

作者：王子轩陈德辉欧斌杨石勇傅蜀燕云南农业大学水利学院云南昆明650201 云南省中小型水利工程智慧管养工程研究中心云南昆明650201

为提高大坝变形预测精度,针对变形数据影响因子间的多重共线性问题,构建了基于核主成分分析(KPCA)、全局搜索策略的鲸鱼优化算法(GSWOA)和门控循环单元(GRU)的组合预测模型。首先利用KPCA对高维变形序列进行降维处理,同时使用GSWOA对GR... 详细信息

为提高大坝变形预测精度,针对变形数据影响因子间的多重共线性问题,构建了基于核主成分分析(KPCA)、全局搜索策略的鲸鱼优化算法(GSWOA)和门控循环单元(GRU)的组合预测模型。首先利用KPCA对高维变形序列进行降维处理,同时使用GSWOA对GRU参数进行优化,进而构建出最优变形预测模型。以小湾特高拱坝变形数据为例,将KPCA-GSWOA-GRU模型与KPCA-WOA-GRU模型、PCA-GSWOA-GRU模型以及传统模型进行预测拟合对比。结果表明:KPCA-GSWOA-GRU模型有效降低了多重共线性问题,且在均方根误差(RMSE)、平均绝对误差(MAE)、平均绝对百分比误差(MAPE)和决定系数(R^(2))等方面均优于对比模型。

关键词：特高拱坝变形监测降维分析核主成分分析(KPCA) 全局搜索策略的鲸鱼优化算法(GSWOA) 门控循环单元(GRU) 小湾水电站

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Ensemble Transform Sensitivity Method for Adaptive Observations

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Advances in Atmospheric Sciences 2016年第1期33卷 10-20页

作者： Yu ZHANG Yuanfu XIE Hongli WANG dehui chen Zoltan TOTH Nanjing University of Information Science and Technology Nanjing 210044 Chinese Academy of Meteorological Science Beijing 100081 Global Systems Division Earth System Research Laboratory NOAA Boulder CO 80305 USA Cooperative Institute for Research in the Atmosphere Colorado State University Fort Collins CO 80523 USA National Meteorological Centr Beijing 100081

The Ensemble Transform（ET） method has been shown to be useful in providing guidance for adaptive observation *** predicts forecast error variance reduction for each possible deployment using its corresponding transformation matrix in an ensemble *** this paper,a new ET-based sensitivity（ETS） method,which calculates the gradient of forecast error variance reduction in terms of analysis error variance reduction,is proposed to specify regions for possible adaptive *** is a first order approximation of the ET;it requires just one calculation of a transformation matrix,increasing computational efficiency（60%-80%reduction in computational cost）.An explicit mathematical formulation of the ETS gradient is derived and *** the ET and ETS methods are applied to the Hurricane Irene（2011） case and a heavy rainfall case for *** numerical results imply that the sensitive areas estimated by the ETS and ET are ***,ETS is much more efficient,particularly when the resolution is higher and the number of ensemble members is larger.

关键词： adaptive observation high impact weather ensemble transform

Label-free quantitative proteomics analysis models in vivo and in vitro reveal key proteins and potential roles in sciatic nerve injury

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生物细胞(英文) 2023年第9期47卷 2069-2080页

作者： YANG GU MINGGUANG BI dehui chen NING NI JIANMING chen Department of Trauma Orthopedics Surgery Ningbo No.6 HospitalNingbo University School of MedicineNingbo315000China Department of Orthopedics Ningbo Medical CenterLihuili HospitalNingbo University School of MedicineNingbo315000China Department of Orthopedic Surgery Fujian Medical University Union HospitalFuzhou350001China School of Medicine Ningbo UniversityNingbo315000China

Background:The underlying mechanism of sciatic nerve injury(SNI)is a common motor functional disorder,necessitates further ***:A rat model of SNI was established,with the injury group subjected to compressive injury of the right sciatic nerve exposed at the midpoint of the thigh and the sham surgery group undergoing the same surgical *** oxygen-glucose deprivation model was employed to simulate in vitro SNI in PC12 *** data acquisition and quality control,differentially expressed proteins(DEPs)in each model were identified through differential analysis,and enrichment analysis was used to explore the potential functions and pathways of the *** diagrams were drawn,and DEPs from both in vivo and in vitro SNI models were imported into the STRING database to construct a protein-protein interaction network and screen for hub ***:After the peptide segments obtained from rat nerve blockade and PC12 cells met quality requirements,258 DEPs were identified in rat nerve samples,and 119 DEPs were screened in PC12 *** analysis revealed that DEPs in the rat model were predominantly concentrated in biological functions such as myogenic cell proliferation and signaling related to lipid and energy *** in the in vitro model were mainly enriched in biological processes such as phagocytosis and were associated with lipid transport and *** hub proteins,amyloid precursor protein(APP)and fibronectin 1(FN1),were identified through MCC,MCODE,and Degree *** PC12 cells and external validation sets showed relatively higher expression of APP and FN1 in injured *** of gene set enrichment analysis indicated that these two proteins were associated with metabolic pathways,such as biosynthesis of glycosaminoglycan chondroitin sulfate and biosynthesis of unsaturated fatty ***:APP and FN1 are potential key molecules involved in SNI and are associated with various metabolic pathways

关键词： Oxygen glucose deprivation Proteomics Sciatic nerve injury Peripheral nerve injury

Towards a standardisation for digital inputs and outputs of protection functions in IEC 60255 series

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Protection and Control of Modern Power Systems 2022年第1期7卷 382-392页

作者： Volker Leitloff Hao chen dehui chen Andrea Bonetti Lei Xu Ahmed Mohamed Carl Byman French Transmission Network Operator Rte ParisFrance State Grid Jiangsu Electric Power Co. Ltd.NanjingChina State Grid Electric Power Institute NanjingChina Royal Institute of Technology StockholmSweden NR Elec-tric Co. Ltd.NanjingChina Scottish and Southern Energy Network(SSEN) GlasgowUK Hitachi Energy VästeråsSweden.

Fully digitalized substations using IEC 61850 process bus are being introduced all over the *** utilities have featured pilot projects,demonstrators or even industrial scale deployment of these Fully Digital Protection,Auto-mation and Control Systems(FD-PACS).Product standards such as profiles for Instrument Transformers have been developed and published(IEC 61869-6 and IEC 61869-9 by TC 38-Instrument Transformers).This raises the question about the standards for digitally interfaced protection *** 2016,IEC TC 95(Measuring relays and protection equipment)charged a working group to investigate this subject and to elaborate recommendations concerning requirements and testing of protection IED with digital inputs and outputs for protection standards(IEC 60255-1xx series).For protection functions,publisher/subscriber based data streams are supposed to comply with IEC 61850 and IEC 61869 *** holds in particular for Sampled Values(SV)representing energising inputs of the protection function,and is also applicable to Generic Object Oriented Substation Event(GOOSE)which can be used for input or output of protection *** attributes of published data depend on the operational and connection status of the function and the hosting *** addition,protection functions have to take into account the information regarding the time synchronisation of the received SV and other *** paper gives an overview of these features and the proposed way to take them into account in the IEC 60255 standard *** describes the progress of WG 2 and relates it to existing standardization documents.

关键词： Process bus Protection function Digital interface SAMU LPIT Standards IEC 61850

The Effects of Land Surface Process Perturbations in a Global Ensemble Forecast System

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Advances in Atmospheric Sciences 2016年第10期33卷 1199-1208页

作者： Guo DENG Yuejian ZHU Jiandong GONG dehui chen Richard WOBUS Zhe ZHANG National Meteorological Center China Meteorological Administration Environmental Modeling Center National Centers for Environmental Prediction5830 University Research Court Institute of Atmospheric Physics Chinese Academy of Sciences

Atmospheric variability is driven not only by internal dynamics, but also by external forcing, such as soil states, SST, snow, sea-ice cover, and so on. To investigate the forecast uncertainties and effects of land surface processes on numerical weather prediction, we added modules to perturb soil moisture and soil temperature into NCEP＇s Global Ensemble Forecast System （GEFS）, and compared the results of a set of experiments involving different configurations of land surface and atmospheric perturbation. It was found that uncertainties in different soil layers varied due to the multiple timescales of interactions between land surface and atmospheric processes. Perturbations of the soil moisture and soil temperature at the land surface changed sensible and latent heat flux obviously, as compared to the less or indirect land surface perturbation experiment from the day-to-day forecasts. Soil state perturbations led to greater variation in surface heat fluxes that transferred to the upper troposphere, thus reflecting interactions and the response to atmospheric external forcing. Various verification scores were calculated in this study. The results indicated that taking the uncertainties of land surface processes into account in GEFS could contribute a slight improvement in forecast skill in terms of resolution and reliability, a noticeable reduction in forecast error, as well as an increase in ensemble spread in an under-dispersive system. This paper provides a preliminary evaluation of the effects of land surface processes on predictability. Further research using more complex and suitable methods is needed to fully explore our understanding in this area.

关键词： perturbation land surface processes GEFS ensemble transform with rescaling

Verification of GRAPES unified global and regional numerical weather prediction model dynamic core

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Chinese Science Bulletin 2008年第22期53卷 3458-3464页

作者： YANG XueSheng HU JiangLin chen dehui ZHANG HongLiang SHEN XueShun chen JiaBin JI LiRen State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Beijing 100081 China National Meteorological Center Beijing 100081 China State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Beijing 100029 China

During the past few years, most of the new developed numerical weather prediction models adopt the strategy of multi-scale technique. Therefore, China Meteorological Administration has devoted to developing a new generation of global and regional multi-scale model since 2003. In order to validate the performance of the GRAPES (Global and Regional Assimilation and PrEdiction System) model both for its scientific design and program coding, a suite of idealized tests has been proposed and conducted, which includes the density flow test, three-dimensional mountain wave and the cross-polar flow test. The density flow experiment indicates that the dynamic core has the ability to simulate the fine scale nonlinear flow structures and its transient features. While the three-dimensional mountain wave test shows that the model can reproduce the horizontal and vertical propagation of internal gravity waves quite well. Cross-polar flow test demonstrates the rationality of both for the semi-Lagrangian departure point calculation and the discretization of the model near the poles. The real case forecasts reveal that the model has the ability to predict the large-scale weather regimes in summer such as the subtropical high, and to capture the major synoptic patterns in the mid and high latitudes.

关键词：数值天气预报气象学天气预测气象分析

代谢组与转录组联合分析毕节市高海拔烟区烟叶类黄酮代谢差异

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烟草科技 2024年第7期57卷 57-64页

作者：申树林黄赟周遵华马敏伦陈德慧马玉玺尹能文李彩斌西南大学农学与生物科技学院重庆市400715 贵州省烟草公司毕节市公司贵州省毕节市551700

为明确毕节市高海拔地区烟叶的代谢特征,分别以该地3个烟叶产区(海拔>1800 m)的韭菜坪2号和云烟87烟叶为材料进行代谢组与转录组联合分析,初步鉴定了韭菜坪2号与云烟87烟叶中的差异代谢物和差异基因,并通过加权基因共表达网络分析筛选... 详细信息

为明确毕节市高海拔地区烟叶的代谢特征,分别以该地3个烟叶产区(海拔>1800 m)的韭菜坪2号和云烟87烟叶为材料进行代谢组与转录组联合分析,初步鉴定了韭菜坪2号与云烟87烟叶中的差异代谢物和差异基因,并通过加权基因共表达网络分析筛选了关键差异基因的模块。结果表明:3个产区的韭菜坪2号与云烟87烟叶代谢差异明显,其中类黄酮代谢物异鼠李素在韭菜坪2号中高积累;同时共鉴定出265个共有的差异表达基因,主要在类黄酮生物合成途径、黄酮与黄酮醇生物合成途径显著富集;加权基因共表达网络分析共鉴定出9个与异鼠李素相关的基因模块,其中2个模块显著富集到类黄酮生物合成途径、黄酮与黄酮醇生物合成途径;进一步研究分析发现,韭菜坪2号中NtPAL1、NtCHIL、NtF3H、NtTT7和NtFLS1基因下调表达可能抑制了苯丙氨酸、山奈酚及其衍生物、槲皮素及其衍生物的积累水平,而NtASMTs、NtROMTs和NtCCoAMT等甲基转移酶基因的上调表达与烟叶中异鼠李素高积累相关。本研究结果初步表明黄酮类生物合成相关途径对韭菜坪2号在高海拔适应性方面具有一定作用,为深入解析韭菜坪2号的高海拔生长适应性机制提供理论指导。

关键词：毕节市高海拔烟区韭菜坪2号云烟87 代谢组转录组类黄酮代谢