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Proof of the Monotonicity of Grid Size and Its Application in Grid-Size Selection for Mesoscale Models

Advances in Atmospheric Sciences 2015年第7期32卷 1005-1015页

作者： WANG Chengxin GAO Shouting RAN lingkun LIANG Li Laboratory of Cloud-Precipitation Physics and Severe Storms Institute of Atmospheric PhysicsChinese Academy of Sciences University of Chinese Academy of Sciences State Key Laboratory of Severe Weather Chinese Academy of Meteorological Sciences Public Weather Service Center China Meteorological Administration National Meteorological Center China Meteorological Administration

Terrain characteristics can be accurately represented in spectrum space. Terrain spectra can quantitatively reflect the effect of topographic dynamic forcing on the atmosphere. In wavelength space, topographic spectral energy decreases with decreasing wavelength, in spite of several departures. This relationship is approximated by an exponential function. A power law relationship between the terrain height spectra and wavelength is fitted by the least-squares method, and the fitting slope is associated with grid-size selection for mesoscale models. The monotonicity of grid size is investigated, and it is strictly proved that grid size increases with increasing fitting exponent, indicating that the universal grid size is determined by the minimum fitting exponent. An example of landslide-prone areas in western Sichuan is given, and the universal grid spacing of 4.1 km is shown to be a requirement to resolve 90% of terrain height variance for mesoscale models, without resorting to the parameterization of subgrid-scale terrain variance. Comparison among results of different simulations shows that the simulations estimate the observed precipitation well when using a resolution of 4.1 km or finer. Although the main flow patterns are similar, finer grids produce more complex patterns that show divergence zones, convergence zones and vortices. Horizontal grid size significantly affects the vertical structure of the convective boundary layer. Stronger vertical wind components are simulated for finer grid resolutions. In particular, noticeable sinking airflows over mountains are captured for those model configurations.

关键词： terrain spectra monotonically increasing function fitting exponent the universal grid size model sensitivity

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土木工程房屋建筑工程混凝土后浇带施工技术研究

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中国厨卫 2024年第7期23卷 113-115,119页

作者：刘璐师飞白灵鲲山东信艺嘉装饰科技有限公司山东青岛266000 青建集团股份公司山东青岛266000

混凝土后浇带是房屋建筑工程中的关键部分,其施工质量和技术水平对建筑结构的安全性、稳定性以及使用寿命有着重要影响,合理应用后浇带施工技术可有效规避地基沉降等问题。基于此,文章结合建筑工程的具体施工,对混凝土后浇带施工技术展... 详细信息

混凝土后浇带是房屋建筑工程中的关键部分,其施工质量和技术水平对建筑结构的安全性、稳定性以及使用寿命有着重要影响,合理应用后浇带施工技术可有效规避地基沉降等问题。基于此,文章结合建筑工程的具体施工,对混凝土后浇带施工技术展开了研究,旨在为该类工程的施工提供参考,进一步提升建筑工程的施工效率和施工质量。

关键词：土木工程建筑工程混凝土后浇带施工技术

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BIM 技术在绿色筑及装配式建筑设计中的应用

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大众科学 2024年第3期45卷 51-54页

作者：白灵鲲师飞刘璐青建集团股份公司山东信艺嘉装饰科技有限公司山东青岛266000

建筑信息模型(Building Information Modeling,BIM)技术作为一种全新的数字化工具,在这一转型中发挥了关键作用,加强对BIM技术的应用研究,对于推进建筑行业的转型与升级有着重要意义。为落实我国的可持续发展战略,建筑行业逐渐采用可持... 详细信息

建筑信息模型(Building Information Modeling,BIM)技术作为一种全新的数字化工具,在这一转型中发挥了关键作用,加强对BIM技术的应用研究,对于推进建筑行业的转型与升级有着重要意义。为落实我国的可持续发展战略,建筑行业逐渐采用可持续的施工模式,其中绿色建筑和装配式建筑设计崭露头角。结合绿色建筑和装配式建筑设计,针对BIM技术的应用展开分析,旨在探讨BIM技术在绿色建筑和装配式建筑设计中的应用,推动绿色建筑和装配式建筑的设计与施工。

关键词： BIM 技术绿色建筑装配式建筑设计

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Height Variation in the Summer Quasi-Zero Wind Layer over Dunhuang, Northwest China: A Diagnostic Study

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Journal of Meteorological Research 2022年第4期36卷 618-630页

作者： Yi YUAN Yi LIU lingkun RAN Hua ZHANG School of Environmental Studies China University of GeosciencesWuhan 430074 Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029 State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081

This study investigates the variation in the stratospheric quasi-zero wind layer(QZWL)over Dunhuang,Gansu Province,China,on 9 August 2.2. using sounding observations from the Dunhuang national reference station and the fifth generation of ECMWF atmospheric reanalysis data(ERA5).The QZWL over Dunhuang was located between 18.6 and 2..4 km on 9 August *** South Asian high(SAH)and subtropical westerly jet jointly affected the *** the SAH retreated westward,the upper-level westerly jet over Dunhuang strengthened,and the jet axis height *** a result,the zonal westerly wind was lifted to a higher altitude,and the wind speed of 100–70 hPa increased,raising the *** addition,the east–west oscillation of the SAH occurred earlier than the adjustment of the QZWL altitude,which can be used as a forecasting indicator for the *** further explore the mechanism responsible for the QZWL adjustment,the forcing terms in the equations for zonal wind,kinetic energy,and vertical wind shear were *** results showed that the upper-level geopotential gradient was the basic physical factor forcing the local change in zonal wind and kinetic *** change in zonal wind and kinetic energy led to the uplift of the *** results revealed that the vertical shear of horizontal wind could adequately indicate the stratospheric QZWL location.

关键词： stratospheric quasi-zero wind layer stratospheric airships South Asian high

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钠通道电压门控1A多态性位点rs2.98771基因型与癫痫患儿抗癫痫药物反应的关系分析

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中华神经医学杂志 2024年第3期23卷 225-232页

作者：李学渊郝凌坤冯旭李雯岳淑敏田龙张家口市第一医院神经内科张家口075000 张家口市第一医院检验科张家口075000 张家口市第一医院儿科张家口075000

目的探讨癫痫患儿钠通道电压门控1A(SCN1A)多态性位点rs2.98771基因型与抗癫痫药物(AED)反应的关系。方法选择张家口市第一医院神经内科自2.2.年6月至2.2.年12.收治的62.癫痫患儿,根据患儿对AED的反应分为AED反应组、AED耐药组,每组3... 详细信息

目的探讨癫痫患儿钠通道电压门控1A(SCN1A)多态性位点rs2.98771基因型与抗癫痫药物(AED)反应的关系。方法选择张家口市第一医院神经内科自2.2.年6月至2.2.年12.收治的62.癫痫患儿,根据患儿对AED的反应分为AED反应组、AED耐药组,每组31例。另外选取同期医院儿科收治的咽炎或轻度肠胃炎患儿31例作为对照组。采用实时定量反转录聚合酶链反应(qRT-PCR)分析患儿SCN1A多态性位点rs2.98771的基因型,比较各组患儿临床资料和SCN1A多态性位点rs2.98771基因型、等位基因的差异。采用相关性分析评价癫痫患儿SCN1A多态性位点rs2.98771基因型与AED反应间的关系。采用多因素Logistic回归分析明确癫痫患儿AED反应的独立影响因素。结果(1)AED反应组和AED耐药组癫痫患儿的首次发作类型、服用的AED差异均有统计学意义(P2.与对照组和AED反应组比较,AED耐药组患儿SCN1A多态性位点rs2.98771的GG基因型发生率较高,AA基因型发生率较低,A等位基因的发生率较低,G等位基因的发生率较高,差异均有统计学意义(P2.98771的AA和AG基因型与左乙拉西坦呈正相关关系(P2.98771的AG基因型与托吡酯、丙戊酸均呈正相关关系(P2.9,95%CI:1.097~9.62.,P=0.033)、SCN1A多态性位点rs2.98771基因型(OR=9.660,95%CI:4.680~19.970,P=0.011)、发作频率(OR=0.160,95%CI:0.032.0.804,P=0.02.)是癫痫患儿AED反应的独立影响因素。结论上次发作后持续时间较短、SCN1A多态性位点rs2.98771为GG基因型、发作频率较高的癫痫患儿易对AED耐药,特别是AG基因型与患儿对托吡酯、丙戊酸耐药有关。

关键词：癫痫儿童钠通道电压门控1A 基因多态性 AED反应基因分型

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Impacts of changes in land cover and topography on a heavy precipitation event in Central Asia

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Atmospheric and Oceanic Science Letters 2022年第4期15卷 44-51页

作者： Shuwen Li Shuai Yang lingkun Ran Laboratory of Cloud-Precipitation Physics and Severe Storms(LACS) Chinese Academy of SciencesInstitute of Atmospheric PhysicsBeijingChina University of Chinese Academy of Sciences BeijingChina

Future variations in precipitation due to the effects of topography and possible trends in land-use change in Central Asia are evaluated by utilizing numerical experiments based on a case *** possible changes in land cover,oasification leads to a 0.2. mm increase in regional-averaged precipitation,accounting for 3.0%of the ***,desertification and urbanization decrease precipitation,by about−5.3%and−4.7%proportionally,mainly through changing the near-surface humidity and thermal environment and related upward transport of heat fluxes in the boundary ***,varied terrain height produces a more prominent impact on precipitation(up to−13.1%and−2..9%in the 1/2.and 1/4 original terrain height runs),mainly via varying the wind field and microphysical processes(low-level jet and cloud).Furthermore,the heavier rainfall happens over the mountains,while the more sensitive response of precipitation to varied topography and land use occurs over the *** the main microphysical conversion pathways of the rainwater budget,the greater peaks of PSMLT(snow melting into raindrops)and PGMLT(graupel melting into raindrops)present over the mountains but not the plains are responsible for the difference in precipitation between the mountains and ***,the more sensitive response of plain rainfall might be related to the rapid transit of rainfall over the plains but prolonged mountainous precipitation lasting together with relatively slowly varying microphysical conversion processes when airflows climb the *** findings of this study have important strategic significance for improving the environment of ecosystems and strengthening the capacity for disaster prevention.

关键词： Topography Land cover Central Asia Heavy precipitation

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Characteristics for the sources and sinks of gravity waves in an orographic heavy snowfall event

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Frontiers of Earth Science 2023年第2期17卷 604-619页

作者： Shuping MA lingkun RAN Jie CAO Baofeng JIAO Kuo ZHOU Key Laboratory of Cloud–Precipitation Physics and Severe Storms Institute of Atmospheric Physics(LACS)Chinese Academy of SciencesBeijing 100029China University of Chinese Academy of Sciences Beijing 100049China Cooperative Institute for Mesoscale Meteorological Studies University of OklahomaNorman OK 73072USA Key Laboratory of Meteorological Disaster(KLME) Ministry of Education&Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters(CIC-FEMD)Nanjing University of Information Science&TechnologyNanjing 210044China

The characteristics of the mesoscale gravity waves during a snowfall event on November 30,2.18 over the Ili Valley and the northern slope of the Tianshan Mountains are analyzed based on the Weather Research and Forecasting model *** vertical distribution of Ro is similar to that of the residual of the nonlinear balance equation(△NBE),with their high-value areas located over the leeward slope and the fluctuations extending upwardly with time,indicating the characteristics of strong ageostrophy and non-equilibrium of atmospheric *** addition,the Ro and(△NBE)are first developed in the lower layers over the leeward slope,revealing that the generation of the gravity waves is closely related to the ***,the topographic uplifting greatly affects this snowfall,and the ageostrophic motion in the whole troposphere and the lower stratosphere,as well as the unbalanced motions between convergence and divergence over the peak and the leeward slope are conductive to the development of the inertia-gravity *** terms of the horizontal scale of the gravity waves,the Barnes’bandpass filter is applied to separate the mesoscale waves and the synoptic-scale basic *** vertical distributions of the vorticity and divergence perturbations have a phase difference ofπ/2.indicating the polarization state of gravity *** analyses on the sources and sinks of gravity waves by the non-hydrostatic wave equation show that the main forcing term for orographic gravity waves is the second-order nonlinear term,whose magnitude mainly depends on the nonlinear thermal *** term is mainly related to the vertical transport of potential temperature *** the snowfall,the potential temperature perturbations are mainly caused by the topographic relief and the release of condensation latent ***,the gravity waves in this snowfall are caused by the topographic forcing and condensation latent heating.

关键词： gravity wave Fourier transform nonlinear balance equation non-hydrostatic wave equation

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On the Mechanism of a Terrain-Influenced Snow Burst Event during Midwinter in Northeast China

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Advances in Atmospheric Sciences 2021年第5期38卷 800-816页

作者： Na LI Baofeng JIAO lingkun RAN Xinyong SHEN Yanbin QI Institute of Atmospheric Physics Chinese Academy of SciencesBeijing 100029China Key Laboratory of Meteorological Disaster Ministry of Education/Joint International Research Laboratory of Climate and Environment Change/Collaborative Innovation Center on Forecast and Evaluation of Meteorological DisastersNanjing University of Information Science and TechnologyNanjing 210044China Jilin Weather Modification Office Changchun 130062China

Short-duration snow bursts with heavy snow represent one type of hazardous weather in winter which can be easily missed by the winter weather warnings but often results in great *** this paper,the mechanism for the occurrence of such events was investigated with the aid of a localized terrain-influenced snow burst event in Northeast *** snow burst was produced by an eastward-moving cold-frontal snowband which encountered the downstream complex terrain of the Changbai Mountains and *** ascertain the role of orography on the snow burst,numerical experiments,together with a parallel sensitivity experiment removing Changbai Mountains,were performed to attempt to distinguish the contributions of cold-frontal system and orographic effects to produce the heavy *** showed that without the influence of Changbai Mountains,the release of conditional instability(CI)and inertial instability(II)within a weak frontogenetical environment was responsible for the snowband *** effects played important roles in enhancing the snowband and increasing the snowfall *** enhancement mechanism was related to the interactions of the cold-frontal snowband and the *** the one hand,orographic frontogenesis and persistent ascent,created by orographic gravity waves over the terrain,greatly enhanced the orographic *** intensification of the lifting promoted the release of CI and thus enhanced the *** the other hand,pre-existing orographic instabilities were released due to the passing of the cold-frontal snowband,which could also serve to intensify the snowband over terrain and thus increase the snowfall.

关键词： terrain-influenced snow burst snowband instability lifting

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VNbTa难熔多主元合金的低温力学性能研究

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热加工工艺 2024年第12期53卷 107-109,115页

作者：张金阳殷学明邹小军孟令坤杨军郭晨辉西安特种设备检验检测院陕西西安710048 川庆钻探长庆井下技术作业公司陕西西安710021 西安理工大学材料科学与工程学院陕西西安710069

通过拉伸测试,研究了等原子比体心立方结构VNbTa中熵合金的低温变形行为。结果表明,该合金具有优异的低温应变硬化能力,这导致其有2.%的断裂伸长率的同时抗拉强度高达1930 MPa。微观结构演化分析揭示,变形过程形成的扭折带及{112.变形... 详细信息

通过拉伸测试,研究了等原子比体心立方结构VNbTa中熵合金的低温变形行为。结果表明,该合金具有优异的低温应变硬化能力,这导致其有2.%的断裂伸长率的同时抗拉强度高达1930 MPa。微观结构演化分析揭示,变形过程形成的扭折带及{112.变形孪晶有效调节了剪切应变,促进了合金塑性和强度的提高。此外,螺型位错缠结、位错带及位错带的交互也对合金强度和加工硬化能力有重要贡献。因此,VNbTa中熵合金优异的低温力学性能归因于{112.变形孪晶、扭折带、螺型位错滑移及交互的协同作用。

关键词：中熵合金拉伸力学性能低温延-脆转变

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数码舌诊仪在中医疾病诊断中的应用进展

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世界科学技术-中医药现代化 2024年第6期26卷 1638-1643页

作者：田鸽张月林王可仪孟令坤尤旭颖王益民天津中医药大学研究生院天津3301617 天津中医药大学中医药研究院天津301617

随着中医舌诊的现代化研究不断推进,舌诊仪对推动舌诊客观化起着不可忽视的作用。传统的中医舌诊只是临床医生对于舌色、舌苔等的肉眼主观判断,而数码舌诊仪以及数字图像处理技术能够将舌色、苔色等通过数字直观地表现出来,得到舌体的... 详细信息

随着中医舌诊的现代化研究不断推进,舌诊仪对推动舌诊客观化起着不可忽视的作用。传统的中医舌诊只是临床医生对于舌色、舌苔等的肉眼主观判断,而数码舌诊仪以及数字图像处理技术能够将舌色、苔色等通过数字直观地表现出来,得到舌体的颜色分布,舌色的饱和度、亮度等参数值,客观地反映机体生理和病理变化。文章简要介绍了数码舌诊仪的主要工作原理、技术参数、图像分割处理方法和舌象分析技术,重点综述了数码舌诊仪在推进中医舌诊客观化的过程中应用于某些常见疾病中的研究现状,并对数码舌诊仪的未来的应用和发展进行了展望。

关键词：数码舌诊仪舌象舌诊客观化研究现状

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