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GRAPES对流尺度集合预报模式中不同尺度初始扰动能量的演变特征

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大气科学 2023年第5期47卷 1541-1556页

作者：马雅楠陈静徐致真王婧卓刘昕中国气象科学研究院北京100081 中国气象局地球系统数值预报中心北京100081 成都信息工程大学成都610225

对流尺度数值预报对初始场的微小扰动非常敏感,且初始扰动的演变具有模式依赖、环流依赖和尺度依赖特征,如何构建合理的初始扰动场是国内外对流尺度集合预报领域尚未解决的难点问题和研究前沿。本文基于中国气象局3 km水平分辨率的GRAPE... 详细信息

对流尺度数值预报对初始场的微小扰动非常敏感,且初始扰动的演变具有模式依赖、环流依赖和尺度依赖特征,如何构建合理的初始扰动场是国内外对流尺度集合预报领域尚未解决的难点问题和研究前沿。本文基于中国气象局3 km水平分辨率的GRAPES(Global/Regional Assimilation and Prediction Enhanced System)对流尺度模式,利用其同化分析系统的背景误差和一个二维随机型,构建大、中、小三个尺度的初始扰动场,并选取中国夏季一次典型的多区域强降水天气个例,开展对流尺度集合预报试验,对比分析了大、中、小尺度初始扰动能量的时空演变和谱分解特征,以期为构建适用于GRAPES对流尺度集合预报的初始扰动场提供依据。研究结果表明,在GRAPES 3 km对流尺度模式中:(1)大、中、小尺度初始扰动总能量的增长过程具有明显差异。大尺度初始扰动总能量随着模式积分呈增长趋势,尤以对流层中高层的持续增长为甚;而中、小尺度初始扰动总能量随着模式积分以日变化为主,表现为下午至傍晚(夜晚至清晨),扰动总能量显著增加(减小),且扰动总能量小尺度分量的日变化占主导,这可能是由于太阳辐射引起地表加热,使得白天的对流活动比夜晚活跃,且对流直接影响了扰动总能量小尺度分量的变化。此外,大、中、小尺度初始扰动总能量增长均以扰动动能增长为主,扰动位能在对流层低层的增长不可忽略。(2)大、中、小尺度初始扰动总能量增长具有环流依赖特征。对北支气流控制的中高纬天气区,在斜压不稳定较强的低槽区,大尺度初始扰动总能量增长突出,而在槽后西北气流区,大、中、小尺度初始扰动总能量均不增长;对南北气流交汇区,仍以大尺度初始扰动总能量增长最为明显;对南海夏季风影响区,大、中、小尺度初始扰动总能量发展均较弱,扰动位能增长与区域降水大值率演变有较好的对应关系。(3)大、中、小尺度初始扰动总能量的谱分析结果显示,不同积分时段扰动总能量的多尺度串级特征有差异。积分前3 h主要为扰动总能量的大尺度分量向小尺度分量降尺度串级,积分6 h后则为中、小尺度分量的升尺度串级。上述研究结果表明,在天气系统复杂、动力不稳定时空分布不均匀的区域(如中国区域)发展对流尺度集合预报时,有必要针对不同的不稳定天气区,构建具有尺度依赖和环流依赖的初始扰动结构。

关键词： GRAPES 3 km 对流尺度模式集合预报不同尺度初始扰动扰动能量演变环流依赖

Wave solutions and numerical validation for the coupled reaction-advection-diffusion dynamical model in a porous medium

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Communications in Theoretical Physics 2022年第12期74卷 9-20页

作者： Ali M Mubaraki Hwajoon Kim R I Nuruddeen Urooj Akram Yasir Akbar Department of Mathematics and Statistics Collage of ScienceTaif UniversityP O Box 11099Taif 21944Saudi Arabia Kyungdong University YangjuRepublic of Korea Department of Mathematics Faculty of ScienceFederal University DutseP O Box 7156 DutseJigawa StateNigeria Department of Mathematics COMSATS University IslamabadLahorePakistan Department of Mathematics COMSATS University Islamabad44000 IslamabadPakistan

The current study examines the special class of a generalized reaction-advection-diffusion dynamical model that is called the system of coupled Burger’s equations.This system plays a vital role in the essential areas of physics,including fluid dynamics and acoustics.Moreover,two promising analytical integration schemes are employed for the study;in addition to the deployment of an efficient variant of the eminent Adomian decomposition method.Three sets of analytical wave solutions are revealed,including exponential,periodic,and dark-singular wave solutions;while an amazed rapidly convergent approximate solution is acquired on the other hand.At the end,certain graphical illustrations and tables are provided to support the reported analytical and numerical results.No doubt,the present study is set to bridge the existing gap between the analytical and numerical approaches with regard to the solution validity of various models of mathematical physics.

关键词： reaction-advection-diffusion model Burger’s equations METEM km NLDM

Assessment and analysis of ecosystem services value along the Yangtze River under the background of the Yangtze River protection strategy

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Journal of Geographical Sciences 2020年第4期30卷 553-568页

作者：郑粮刘海黄跃飞殷守敬金贵 Faculty of Resources and Environmental Science Hubei UniversityWuhan 430062China Ministry of Environmental Protection Satellite Environment CenterBeijing 100094China College of Urban and Environment Science Central China Normal UniversityWuhan 430079China School of Remote Sensing and Information Wuhan UniversityWuhan 430062China

The Yangtze River is the third largest river in the world and the longest and largest river in China.China has adopted a national strategy to protect the Yangtze River.A better understanding of the ecosystem services value along the Yangtze River would provide support for the Yangtze River protection strategy.Using Costanza’s method to estimate the ecosystem services value,the value of 10 ecosystem services was estimated within 1 km and 2 km from the Yangtze River in 2017.These 10 services were derived from the four established groupings of provisioning,regulating,supporting,and cultural services.This study compared and analyzed the changes in the ecosystem services value in the upper,middle,and lower reaches of the river,and in provinces,cities,and villages along the Yangtze River.The total ecosystem services value within 1 km and 2 km from the river was 37.208 and 43.769 billion yuan,respectively.Within 1 km,the ecosystem services value in the middle reaches was 12.93 billion yuan,while the next highest value was in the upper reaches at 12.45 billion yuan,and the downstream area had the smallest value of 11.855 billion yuan.Within 2 km,the value of upstream ecosystem services was the highest at 16.31 billion yuan,while the second highest value was in the middle reaches at 14.376 billion yuan,and the smallest value was in the downstream area at 13.083 billion yuan.In the Yangtze River Basin,regulating services played a leading role,accounting for 81.6%and 78.9%of the ecosystem services value within 1 km and 2 km from the river,respectively.Among the 10 ecosystem services,hydrological regulation was the most important,while the value of raw material production made the smallest contribution.Among the provinces and cities along the Yangtze River,the highest ecosystem services value was in Hubei Province,while the lowest values were in Shanghai and the Qinghai-Tibet Plateau.If villages within 1 km and 2 km from the river were to be relocated,the total regional ecological value would increase by 527 and 975 million

关键词： Yangtze River Basin 1 km along the Yangtze River 2 km along the Yangtze River value assessment method ecosystem services

THE INHIBITORY EFFECT OF DIFFERENT CONCENTRATIONS OF MOXA SMOKE ON CENTRAL NERVOUS SYSTEM IN km MICE

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Journal of Integrative Medicine 2014年第3期 236-237页

作者： Jia Yang Baixiao Zhao Li Han Lei Wang lixing Lao Hongsheng Chang Beijing University of Chinese Medicine

Objective: To observe the effects of different concentrations of moxa smoke on the central nervous system in km mice.Methods: Forty km mice(half male and half female) were randomly assigned(n=10/group) to a negative control group(N) or one of three moxa smoke groups(% opacity): L1(low concentration, 0.4%), M1(middle concentration, 2%), H1(high concentration, 15%).Mice in moxa smoke groups were exposed at respective concentrations in a dynamic gas exposure cabinet 200 min a day for 7 days.Mice in the negative control group were in the same cabinet without any interventions.Changes of general activities, locomotor activities, coordinated movement, sleep duration induced by subthreshold dose of pentobarbital sodium and the sleep rate induced by subthreshold dose of pentobarbital sodium in the mice with different smoke concentrations were recorded.Results: Mice in smoke groups had no significant change in general activities, locomotor activities, and coordinated movement compared with negative group(P>0.05); the sleep duration time in smoke groups showed no significant change in contrast with the negative group, but the sleep time in L1 and M1 groups tended to be longer than the negative and H1 groups.The sleep rate in M1 and L1 groups increased significantly compared withthe negative group(P<0.05).Conclusion: Medium concentration of smoke shows inhibitory effect on central nervous system in mice, but high concentration of smoke shows both inhibitory and stimulating effects.Our findings suggest that moxa smoke may have hypnotic and tranquilizing effects on central nervous system, which varies according to the concentrations of the moxa smoke.The mechanism needs a further study.

关键词： km

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TEM处理km小鼠的遗传易位测定

中国医学科学院学报 1984年第6期6卷 425-428页

作者：王菊凝张明中国医学科学院卫生研究所中国医学科学院卫生研究所北京

用km小鼠建立了最终鉴定环境化学物,致变性的遗传易位测定方法,结果表明本实验系统及技术措施是满意的。

关键词：生育力雄鼠小鼠小家鼠精母细胞 TEM 实验动物 km

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高速切削中的刀柄技术

制造技术与机床 2006年第7期 20-23页

作者：赵宏林高立新丁庆新中国石油大学(北京)机电学院北京102249 北京工业大学机电学院北京100022

在论述高速切削技术特点的基础上,着重研究了高速切削技术中的刀柄结构,包括HSK、km及CAPTO,比较了常用的BT刀柄与HSK、km刀柄的拉紧特性,简述了高速旋转所带来的特殊的动平衡问题,指出了高速刀柄技术的发展趋势。

关键词：高速切削刀柄 HSK km

我国优秀女子20km竞走运动员后半程竞走技术的运动学研究

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中国体育科技 2007年第4期43卷 53-59,67页

作者：李建臣吴玲敏首都体育学院技术学部北京100088 湖南工程学院湖南湘潭411100

运用三维运动学分析方法,对参加国际田联竞走挑战赛女子20km比赛前8名运动员后半程中一个复步进行解析。结果表明,我国运动员在后半程中,运用的是步长较短,步频较快的技术风格;腾空时间总体上处于犯规时限的下限,膝关节从着地瞬间直至... 详细信息

运用三维运动学分析方法,对参加国际田联竞走挑战赛女子20km比赛前8名运动员后半程中一个复步进行解析。结果表明,我国运动员在后半程中,运用的是步长较短,步频较快的技术风格;腾空时间总体上处于犯规时限的下限,膝关节从着地瞬间直至垂直支撑面保持了可见的伸直状态,但在最后冲刺阶段,膝角出现了模糊伸直过程;身体重心垂直位移、头顶位置上下起伏均高于世界优秀运动员平均水平,这既与踝关节后蹬伸展离地时机偏早、用力动作不充分有关,也与着地瞬间摆动腿前摆后的前伸着地动作不够积极有关。在注意后蹬动作的同时,还应强化摆动腿积极的前摆着地动作。躯干倾角基本处于正常范围之内,但左、右腿蹬伸用力不均衡造成身体重心左、右偏差较大的情况容易导致动作外观不稳定而被判罚技术犯规。我国运动员肩髋扭转角度较小是导致步长相对较短的一个重要成因。

关键词： 20 km 竞走女子优秀运动员运动学技术分析中国

<i>In Vitro</i>and <i>in Vivo</i>(Mouse) Evaluation of Drug-Drug Interactions of Repaglinide with Anti-HIV Drugs

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Pharmacology & Pharmacy 2015年第4期6卷 241-246页

作者： Vijay Saradhi Mettu P. Yadagiri Swami P. Abigna A. Ravinder Nath Geeta Sharma Department of Pharmacy University College of Technology Osmania University Hyderabad India Department of Chemistry University College of Science Osmania University Hyderabad India Forma Therapeutics Singapore Singapore City Singapore

Repaglinide is type 2 short acting anti-diabetic drug which is primarily metabolized by CYP2C8 and CYP3A4 and is also a substrate of influx transporter OATP1B1. HIV drugs are potent inhibitors of CYP3A4 and OATP transporters. Several drug-drug interactions (DDIs) were noticed when protease inhibitors (PIs) coadministered with drugs metabolized by CYP3A4. The PIs are also potent mechanism based inhibitors, out which ritonavir is most potent. In the current study we evaluated in vitro (mouse and human liver microsomes) and in vivo DDIs of repaglinide with anti-HIV drugs. Out of the following tested drugs (Amprenavir, Indinavir, Nelfinavir, Ritonavir, Saquinavir, Delavirdine, Maraviroc, Efavirenz, Nevirapine and Ketoconazole) Amprenavir (APV), Ritonavir (RTV) and Ketoconazole (KTZ) showed inhibition of OH-repaglinide formation in human and mouse liver microsomes. The positive reversible inhibitions were further tested for irreversible inhibitions where we didn’t observe any irreversible inhibitions. In vitro inhibitions were further evaluated in the in vivo pharmacokinetics (mouse) where repaglinide pharmacokinetics was altered by RTV and KTZ. The DDIs in both studies were very strong;the dose of repaglinide is reduced to 20 fold. In conclusion, there could be possible DDIs when RTV dosed with repaglinide;we have also demonstrated that mouse could be useful preclinical tool when used in conjunction with in vitro screening models for DDIs.

关键词： Repaglinide Drug-Drug Interaction Repaglinide km Repaglinide Bioanalytical Method

知识管理技术与e-Learning资源库建设研究

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电化教育研究 2003年第5期24卷 53-58页

作者：张一春祝智庭南京师范大学现代教育技术中心江苏南京210097

资源库是网络化学习的重要基础 ,是教育领域一个全新的增长点。而知识管理是目前在国际管理领域成功运作的一种科学的、高效的管理办法。把知识管理技术引入资源库建设 ,是一种尝试 ,它可以使我们高瞻远瞩 ,清晰地把握资源库建设的方方... 详细信息

资源库是网络化学习的重要基础 ,是教育领域一个全新的增长点。而知识管理是目前在国际管理领域成功运作的一种科学的、高效的管理办法。把知识管理技术引入资源库建设 ,是一种尝试 ,它可以使我们高瞻远瞩 ,清晰地把握资源库建设的方方面面 ,成功建设与管理 e- L earning资源库。本文从资源库的现状出发 ,剖析和介绍了知识管理技术 ,并用知识管理技术分析 e- L earning资源库建设的几个问题 ,探讨教学资源库建设的途径与方法 ,并对资源库的发展提出了一些看法。

关键词：知识管理 km e-Learning 资源库