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Impact of a Three-Dimensional Reference State in a Global Semi-Implicit Semi-Lagrangian Non-Hydrostatic Atmospheric Model on Yin–Yang Grids

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Journal of Meteorological Research 2024年第5期 901-922页

作者： Yifan ZHAO Xindong PENG dehui chen Yerong FENG Xiaohan LI Juan GU State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological Administration College of Earth and Planetary Sciences University of Chinese Academy of Sciences CMA Earth System Modeling and Prediction Centre China Meteorological Administration (CMA) Guangzhou Institute of Tropical and Marine Meteorology China Meteorological Administration College of Aviation Meteorology Civil Aviation Flight University of China

The definition of a reference state close to the realistic atmosphere in an atmospheric model is essential for deriving prognostic deviations and improving numerical accuracy. In this study, a new dynamical framework allowing easy switching between a one-dimensional (1D) and a three-dimensional (3D) time-independent reference state is developed for the semi-implicit semi-Lagrangian solver in a global non-hydrostatic atmospheric model on Yin–Yang grids. The 3D reference state is introduced with consideration of additional horizontal gradient terms of referencestate terms, which is different from the 1D reference *** is characterized by reduced magnitude of deviations,more accurate pressure gradient force, as well as alleviated numerical noise. Four idealized benchmark tests and multiple full-physics real-case forecasts are carried out to assess the impact of the 3D and 1D reference states. The 3D reference state shows significant advantages in the simulation of atmospheric transport and wave propagation in the idealized experiments. In the real-case forecasts, batched forecasts from June to August 2021 show a comprehensive improvement in medium-range prediction by using the 3D reference state. The new scheme achieves an enhanced prediction skill for large-scale circulation and extends the effective forecast period by 0.8 days in the Northern Hemisphere.

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Preliminary Model Study for Forecasting a Hot Weather Process in Guangdong Province Using CMA-TRAMS

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Atmospheric and Climate Sciences 2024年第1期14卷 101-117页

作者： Wenfan Wang Jiemin Zhan dehui chen Zitong chen Yanxia Zhang Qing Fan Guangfeng Dai Yingying Luo Aifen Ye Department of Applied Mechanics and Engineering Shenzhen Campus of Sun Yat-sen University Shenzhen Guangdong China Guangzhou Institute of Tropical and Marine Meteorology/Guangdong Provincial Key Laboratory of Regional Numerical Weather Prediction CMA Guangzhou China

In this paper, the CMA-TRAMS tropical high-resolution system was used to forecast a typical hot weather process in Guangdong, China with different horizontal resolutions and surface coverage. The results of resolutions of 0.02° and 0.06° were presented with the same surface coverage of the GlobeLand30 V2020, companies with the results of resolution 0.02° with the USGS global surface coverage. The results showed that, on the overall assessment the 2 km model performed better in forecasting 2 m temperature, while the 6 km model was more accurate in predicting 10 m wind speed. In the evaluation of representative stations, the 2 km model performed better in forecasting 2 m temperature and 2 m relative humidity at the coastal stations, and the 2 km model was also better in forecasting 2 m pressure at the representative stations. However, the 6 km model performed better in forecasting 10 m wind speed at the representative stations. Furthermore, the 2 km model, owing to its higher horizontal resolution, presented a more detailed stratification of various meteorological field maps, allowing for a more pronounced simulation of local meteorological element variations. And the use of the surface coverage data of the GlobeLand30 V2020 improved the forecasting of 2 m temperature, and 10 m wind speed compared to the USGS surface coverage data.

关键词： High-Resolution Numerical Model CMA-TRAMS Model Test Evaluation Surface Coverage Numerical Simulation

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数字普惠金融赋能粮食体系韧性——基于空间溢出效应视角分析

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中国农业资源与区划 2024年第5期45卷 74-84页

作者：李明亮陈德慧余国新新疆农业大学经济管理学院上海工程技术大学管理学院

[目的]探究数字普惠金融对粮食体系韧性的影响，为保障国家粮食安全，实现农业农村现代化指明新的方向。[方法]文章基于2011—2020年全国31个省（市、区，不含港澳台地区）的面板数据，从抵抗能力、适应能力、变革能力3个维度出发构建... 详细信息

[目的]探究数字普惠金融对粮食体系韧性的影响，为保障国家粮食安全，实现农业农村现代化指明新的方向。[方法]文章基于2011—2020年全国31个省（市、区，不含港澳台地区）的面板数据，从抵抗能力、适应能力、变革能力3个维度出发构建粮食体系韧性综合评价指标体系，运用熵值法测算粮食体系韧性水平，利用空间计量模型实证检验数字普惠金融对粮食体系韧性的空间溢出效应和异质性。[结果]数字普惠金融对粮食体系韧性具有显著的正向空间溢出效应，即数字普惠金融能够提升当地及邻近地区的粮食体系韧性；数字普惠金融的覆盖广度、使用深度和数字化程度均有助于粮食体系韧性的提升；不同区域的数字普惠金融对粮食体系韧性的影响差异显著，其中主销区数字普惠金融对粮食体系韧性的提升作用最大，主产区和产销平衡区次之。[结论]应大力发展数字普惠金融，推动农村数字普惠金融基础设施建设，提高农户金融素养，创新金融服务模式和数字技术，因地制宜发挥各产区优势，并加强地区间的相互合作。

关键词：数字普惠金融粮食体系韧性粮食安全空间溢出效应异质性分析

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Air pumping for alleviation of heavy smog in Beijing

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Science China Earth Sciences 2018年第7期61卷 973-979页

作者： Yaping SHAO Sven ULBRICH dehui chen Institute for Geophysics and Meteorology Department of GeosciencesUniversity of CologneCologne 50923Germany China Meteorological Administration Beijing 100081China

Beijing often suffers under heavy *** such events which occur mostly in autumn and winter,people are desperate for fresh *** formation of heavy smog is due to foremost human induced air pollution,but geographic and meteorological conditions,especially below a surface inversion,play an important *** propose to destroy the inversion by pumping air from above the inversion layer to the surface layer to alleviate the severity of the *** long-term air quality improvement depends on the reduction of air pollution emission,air pumping may provide relief in the interim for the Beijing *** estimate that an air pumping at a rate 2×10~7m^3s^(–1)can lead to significantly improved air quality in Beijing,due to(1)direct clean air input;(2)increased instability and vertical mixing and(3)a positive radiation-mixing *** pumping requires an energy input of 10 GW,comparable with the energy consumption in Beijing for air conditioning in *** propose to use wind energy from Inner Mongolia for the pumping,which has currently an installed wind energy capacity of 70GW.

关键词： Beijing air quality Air pumping Numerical modelling Inversion

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Properties of High-Order Finite Difference Schemes and Idealized Numerical Testing

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Advances in Atmospheric Sciences 2021年第4期38卷 615-626页

作者： Daosheng XU dehui chen Kaixin WU Guangzhou Institute of Tropical and Marine Meteorology/Key Laboratory of Regional Numerical Weather Prediction Guangzhou 510640China National Meteorological Center Beijing 100081China

Construction of high-order difference schemes based on Taylor series expansion has long been a hot topic in computational mathematics, while its application in comprehensive weather models is still very rare. Here, the properties of high-order finite difference schemes are studied based on idealized numerical testing, for the purpose of their application in the Global/Regional Assimilation and Prediction System(GRAPES) model. It is found that the pros and cons due to grid staggering choices diminish with higher-order schemes based on linearized analysis of the one-dimensional gravity wave equation. The improvement of higher-order difference schemes is still obvious for the mesh with smooth varied grid distance. The results of discontinuous square wave testing also exhibits the superiority of high-order schemes. For a model grid with severe non-uniformity and non-orthogonality, the advantage of high-order difference schemes is inapparent, as shown by the results of two-dimensional idealized advection tests under a terrain-following coordinate. In addition, the increase in computational expense caused by high-order schemes can be avoided by the precondition technique used in the GRAPES model. In general, a high-order finite difference scheme is a preferable choice for the tropical regional GRAPES model with a quasi-uniform and quasi-orthogonal grid mesh.

关键词： high-order difference scheme dispersion uniform orthogonal computational efficiency

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TikTok Shop在东南亚五国的发展策略研究——基于SWOT-AHP模型的分析

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北方经贸 2024年第6期 23-26,31页

作者：陈德慧崔瑞哈尔滨商业大学经济学院哈尔滨150028

伴随全球电商渗透率持续提升,我国的一批优秀企业纷纷开通跨境电商平台,以更好地助力品牌出海。字节跳动旗下的全球最大的短视频网站之一Tiktok就是其中的典型代表,其在东南亚五国开通了Titok Shop,为我国企业开拓东南亚市场搭建优质的... 详细信息

伴随全球电商渗透率持续提升,我国的一批优秀企业纷纷开通跨境电商平台,以更好地助力品牌出海。字节跳动旗下的全球最大的短视频网站之一Tiktok就是其中的典型代表,其在东南亚五国开通了Titok Shop,为我国企业开拓东南亚市场搭建优质的跨境电商平台。首先总结了TikTok Shop在东南亚五国开展业务的现状,采用SWO T-AHP方法对TikTok Shop在东南亚五国的发展进行深入剖析,认为其战略发展方向应以SO战略为主;提出TikTok Shop应完善跨境电商物流体系、深耕本土化运营、完善品牌化建设、加强基础设施建设、培养跨境电商复合型人才等发展策略,以期为我国企业搭建优质的跨境电商平台,助力我国品牌出海提供有价值的参考。

关键词：跨境电商 SWOT-AHP分析东南亚 TikTok Shop

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儿童气道狭窄的软式支气管镜介入治疗进展

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广西医学 2024年第8期46卷 1140-1145页

作者：吴上志陈德晖广州医科大学附属第一医院儿科广东省广州市510120

气道狭窄作为一种严重的临床病症,可显著影响患儿的呼吸功能,对婴幼儿的影响更为严重。支气管镜作为一种微创诊治工具,在儿童气道狭窄治疗领域中扮演至关重要的角色。它不仅能够准确诊断气道狭窄的病因及程度,还能够实施多种介入治疗,... 详细信息

气道狭窄作为一种严重的临床病症,可显著影响患儿的呼吸功能,对婴幼儿的影响更为严重。支气管镜作为一种微创诊治工具,在儿童气道狭窄治疗领域中扮演至关重要的角色。它不仅能够准确诊断气道狭窄的病因及程度,还能够实施多种介入治疗,例如球囊扩张术、支架置入术、冷冻消融术等,可达到有效缓解狭窄、改善通气功能的目的。随着医疗技术的持续革新,支气管镜的诊疗应用范围不断拓宽,安全性也逐步增强。然而,该技术在儿科领域的实际操作过程中仍存在较多的挑战,如操作难度较大、器械适配性不足等问题。本文对软式支气管镜介入治疗技术在儿童气道狭窄中的应用情况进行总结,探讨儿童气道狭窄的综合介入策略,并从技术创新、医疗器械研发及多学科协作等方面进行展望,旨在为儿童气道狭窄的诊疗提供更加优质和高效的解决方案。

关键词：气道狭窄儿童支气管镜介入治疗综合治疗综述

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经支气管镜冷冻技术在儿科呼吸系统疾病中的应用

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中国小儿急救医学 2024年第8期31卷 566-570页

作者：吴上志陈德晖广州医科大学附属第一医院儿科 510120

经支气管镜冷冻技术在呼吸系统疾病的治疗领域已取得了显著的成果。该技术利用低温冷冻的原理,对病变组织进行处理,已逐步在多种呼吸系统疾病诊治中广泛应用,包括冻融与冻切技术。随着支气管镜介入技术的不断进步,冷冻技术的应用范围亦... 详细信息

经支气管镜冷冻技术在呼吸系统疾病的治疗领域已取得了显著的成果。该技术利用低温冷冻的原理,对病变组织进行处理,已逐步在多种呼吸系统疾病诊治中广泛应用,包括冻融与冻切技术。随着支气管镜介入技术的不断进步,冷冻技术的应用范围亦逐渐扩大,其安全性与有效性也得到了提高。文章介绍了经支气管镜冷冻技术及其在儿科介入呼吸病学中的应用,旨在让更多儿科同行了解该技术,在呼吸介入治疗中更有效地应用该技术。

关键词：经支气管镜冷冻技术呼吸系统疾病儿童

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TEMU海外拓展面临的问题及对策研究

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北方经贸 2024年第8期 62-66页

作者：陈德慧郭明英哈尔滨商业大学经济学院哈尔滨150028

近年来,跨境电商取得了蓬勃发展,越来越多的国内电商企业开始拓展海外市场。本文从产品、运营、营销和物流四个方面梳理了拼多多旗下跨境电商平台TEMU的海外拓展现状,分析了其在物流效率、流量成本、平台机制、海外运营环境等方面的问题... 详细信息

近年来,跨境电商取得了蓬勃发展,越来越多的国内电商企业开始拓展海外市场。本文从产品、运营、营销和物流四个方面梳理了拼多多旗下跨境电商平台TEMU的海外拓展现状,分析了其在物流效率、流量成本、平台机制、海外运营环境等方面的问题,并针对不同的问题提出了相应的对策,旨在提高TEMU在海外市场的国际竞争力。

关键词： TEMU 海外拓展流量成本品牌优势

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Improvement of the Semi-Lagrangian Advection Scheme in the GRAPES Model:Theoretical Analysis and Idealized Tests

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Advances in Atmospheric Sciences 2014年第3期31卷 693-704页

作者： HUANG Bo chen dehui LI Xingliang LI Chao Chinese Academy of Meteorological Sciences Numerical Weather Prediction Center China Meteorological Administration University of Chinese Academy of Sciences

ABSTRACT The Global/Regional Assimilation and PrEdiction System （GRAPES） is the newgeneration numerical weather predic- tion （NWP） system developed by the China Meteorological Administration. It is a fully compressible non-hydrostatical global/regional unified model that uses a traditional semi-Lagrangian advection scheme with cubic Lagrangian interpola tion （referred to as the SL_CL scheme）. The SL_CL scheme has been used in many operational NWP models, but there are still some deficiencies, such as the damping effects due to the interpolation and the relatively low accuracy. Based on Reich＇s semi-Lagrangian advection scheme （referred to as the R2007 scheme）, the Re_R2007 scheme that uses the low- and high-order B-spline function for interpolation at the departure point, is developed in this paper. One- and two-dimensional idealized tests in the rectangular coordinate system with uniform grid cells were conducted to compare the Re..R2007 scheme and the SL_CL scheme. The numerical results showed that：（1） the damping effects were remarkably reduced with the Re_R2007 scheme; and （2） the normalized errors of the Re_R2007 scheme were about 7.5 and 3 times smaller than those of the SL_CL scheme in one- and two-dimensional tests, respectively, indicating the higher accuracy of the Re..R2007 scheme. Furthermore, two solid-body rotation tests were conducted in the latitude-longitude spherical coordinate system with non uniform grid cells, which also verified the Re_R2007 scheme＇s advantages. Finally, in comparison with other global advection schemes, the Re_R2007 scheme was competitive in terms of accuracy and flow independence. An encouraging possibility for the application of the Re_R2007 scheme to the GRAPES model is provided.

关键词： numerical models semi-Lagrangian method advection scheme numerical accuracy spline interpolation

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