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Long-term Trend and Fractal of Annual Runoff Process in Mainstream of Tarim River

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Chinese Geographical Science 2008年第1期18卷 77-84页

作者： xu Jianhua CHEN yaning LI Weihong DONG Shan Key Laboratory of Geographic Information Science Ministry of Education Shanghai 200062 China Department of Geography East China Normal University Shanghai 200062 China The Key Laboratory of Oasis Ecology and Desert Environment Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China

Based on the time series data from the Aral hydrological station for the period of 1958-2005,the paper re-veals the long-term trend and fractal of the annual runoff process in the mainstream of the Tarim River by using the wavelet analysis method and the fractal *** main conclusions are as follows:1)From a large time scale point of view,*** time scale of 16(24)years,the annual runoff basically shows a slightly decreasing trend as a whole from 1958 to *** the time scale is reduced to 8(23)or 4(22)years,the annual runoff still displays the basic trend as the large time scale,but it has fluctuated more obviously during the period.2)The correlation dimension for the annual runoff process is 3.4307,non-integral,which indicates that the process has both fractal and chaotic *** correlation dimension is above 3,which means that at least four independent variables are needed to describe the dynamics of the annual runoff process.3)The Hurst exponent for the first period(1958-1973)is 0.5036,which equals 0.5 approximately and indicates that the annual runoff process is in *** Hurst exponents for the second(1974-1989)and third(1990-2005)periods are both greater than 0.50,which indicate that the annual runoff process showed a long-enduring characteristic in the two *** Hurst exponent for the period from 1990 to 2005 indi-cates that the annual runoff will show a slightly increasing trend in the 16 years after 2005.

关键词：径流子波塔里木河一年生植物

Climate Change and Its Effects on Runoff of Kaidu River, Xinjiang, China:A Multiple Time-scale Analysis

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Chinese Geographical Science 2008年第4期18卷 331-339页

作者： xu Jianhua CHEN yaning JI Minhe LU Feng Key Laboratory of Geographic Information Science Ministry of Education Shanghai 200062 China The Research Center for East-West Cooperation in China East China Normal University Shanghai 200062 China The Key Laboratory of Oasis Ecology and Desert Environment Xinjiang Institute of Ecology and Geography Chinese Academy of Sciences Urumqi 830011 China

This paper applied an integrated method combining grey relation analysis, wavelet analysis and statistical analysis to study climate change and its effects on runoff of the Kaidu River at multi-time scales. Major findings are as follows: 1) Climatic factors were ranked in the order of importance to annual runoff as average annual temperature, average temperature in autumn, average temperature in winter, annual precipitation, precipitation in flood season, average temperature in summer, and average temperature in spring. The average annual temperature and annual precipi- tation were selected as the two representative factors that impact the annual runoff. 2) From the 32-year time scale, the annual runoff and the average annual temperature presented a significantly rising trend, whereas the annual precipita- tion showed little increase over the period of 1957-2002. By changing the time scale from 32-year to 4-year, we ob- served nonlinear trends with increasingly obvious oscillations for annual runoff, average annual temperature, and annual precipitation. 3) The changes of the runoff and the regional climate are closely related, indicating that the runoff change is the result of the regional climate changes. With time scales ranging from 32-year, 16-year, 8-year and to 4-year, there are highly significant linear correlations between the annual runoff and the average annual temperature and the annual precipitation.

关键词：中国新疆河流温度降水非线性趋势

Hydrology and water resources variation and its response to regional climate change in Xinjiang

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Journal of Geographical Sciences 2010年第4期20卷 599-612页

作者： xu Changchun CHEN yaning YANG Yuhui HAO Xingming SHEN Yongping Key Laboratory of Oasis Ecology and Desert Environment Xinjiang Institute of Ecology and Geography CAS Urumqi 830011 China Key Laboratory of Oasis Ecology School of Resources and Environmental Science Xinjiang University Urumqi 830046 China Cold and Arid Regions Environmental and Engineering Research Institute CAS Lanzhou 730000 China

Based on the surface runoff, temperature and precipitation data over the last 50 years from eight representative rivers in Xinjiang, using Mann-Kendall trend and jump detection method, the paper investigated the long-term trend and jump point of time series, the surface runoff, mean annual temperature and annual precipitation. Meanwhile, the paper analyzed the relationship between runoff and temperature and precipitation, and the flood frequency and peak flow. Results showed that climate of all parts of Xinjiang conformably has experienced an increase in temperature and precipitation since the mid-1980s. Northern Xinjiang was the area that changed most significantly followed by southern and eastern Xinjiang. Affected by temperature and precipitation variation, river runoff had changed both inter-annually and intra-annually. The surface runoff of most rivers has increased significantly since the early 1990s, and some of them have even witnessed the earlier spring floods, later summer floods and increasing flood peaks. The variation characteristics were closely related with the replenishment types of rivers. Flood frequency and peak flow increased all over Xinjiang. Climate warming has had an effect on the regional hydrological cycle.

关键词： hydrology and water resources climate change Xinjiang

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基于稳定学习的图神经网络模型

湖南理工学院学报（自然科学版） 2023年第4期36卷 16-18页

作者：李文彬许雁玲钟志楷杨勃湖南理工学院信息科学与工程学院湖南岳阳414006

图神经网络(GNN)在对图样本进行分类工作时效果差强人意,无法发现数据背后真实的功能网络.为提高图神经网络在图分类上的稳定性,提出一种基于稳定学习的图神经网络模型(Stable-GNN).该模型将基于随机傅里叶特征的样本加权采样干预技术... 详细信息

图神经网络(GNN)在对图样本进行分类工作时效果差强人意,无法发现数据背后真实的功能网络.为提高图神经网络在图分类上的稳定性,提出一种基于稳定学习的图神经网络模型(Stable-GNN).该模型将基于随机傅里叶特征的样本加权采样干预技术与图神经网络结合,尝试在神经网络训练过程中,剔除虚假因果特征,提高模型在图样本分类上的稳定性.实验结果表明,该方法能有效发现真实的关联网络,提高图网络的稳定性.

关键词：图神经网络稳定学习图样本分类

维普期刊数据库博看期刊

Spatial and temporal trends of climate change in Xinjiang, China

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Journal of Geographical Sciences 2011年第6期21卷 1007-1018页

作者： LI Qihu CHEN yaning SHEN Yanjun LI Xingong xu Jianhua Key Lab of GIScience of the Ministry of Education East China Normal University Shanghai 200062 China State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and Geography CAS Urumqi 830002 China Key Laboratory of Agricultural Water Resources Center for Agricultural Resources Research CAS Shijiazhuang 050021 China Department of Geography University of Kansas Lawrence KS 66045 USA

Temperature and precipitation time series datasets from 1961 to 2005 at 65 meteorological stations were used to reveal the spatial and temporal trends of climate change in Xinjiang, China. Annual and seasonal mean air temperature and total precipitation were analyzed using Mann-Kendall （MK） test, inverse distance weighted （IDW） interpolation, and R/S methods. The results indicate that：（1） both temperature and precipitation increased in the past 45 years, but the increase in temperature is more obvious than that of precipitation; （2） for temperature increase, the higher the latitude and the higher the elevation the faster the increase, though the latitude has greater influence on the increase. Northern Xinjiang shows a faster warming than southern Xinjiang, especially in summer; （3） increase of precipitation occurs mainly in winter in northern Xinjiang and in summer in southern Xinjiang. lli, which has the most precipitation in Xinjiang, shows a weak increase of precipitation; （4） although both temperature and precipitation increased in general, the increase is different inside Xinjiang; （5） Hurst index （H） analysis indicates that climate change will continue the current trends.

关键词： climate change MK test Xinjiang IDW R/S

2018—2023年中国森林脑炎流行特征分析

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中国国境卫生检疫杂志 2024年第3期47卷 291-296页

作者：刘亚宁殷启凯曹玉玺崔倩倩聂凯许松涛李樊王环宇中国疾病预防控制中心病毒病预防控制所北京102206 传染病溯源预警与智能决策全国重点实验室中国疾病预防控制中心病毒病预防控制所

目的分析2018—2023年中国森林脑炎的流行特征,揭示其发生规律,为制定森林脑炎的防控策略提供科学依据。方法利用中国疾病预防控制信息系统,收集2018—2023年间中国森林脑炎病例数据,采用描述性流行病学方法进行分析。结果2018—2023年... 详细信息

目的分析2018—2023年中国森林脑炎的流行特征,揭示其发生规律,为制定森林脑炎的防控策略提供科学依据。方法利用中国疾病预防控制信息系统,收集2018—2023年间中国森林脑炎病例数据,采用描述性流行病学方法进行分析。结果2018—2023年,全国森林脑炎报告病例共656例,年平均发病率为0.008/10万,死亡2例,病死率为0.30%。报告病例主要集中在内蒙古自治区、黑龙江省和吉林省,占总报告病例的98.6%,该3省(地区)年平均发病率0.06/10万~0.21/10万,年平均实验室确诊率为53.35%,存在显著的地区间差异(P<0.05)。森林脑炎发病高峰在5-7月,其间报告病例数占总病例数的89.33%。发病人群主要为农民、家务及待业人员和工人,构成比分别为46.95%、27.13%、11.43%。全国报告病例主要集中于40~69岁年龄组,其中50~59岁年龄组占比最高,为37.65%,且男性发病多于女性。结论2018—2023年中国森林脑炎报告病例主要集中于内蒙古自治区东部、黑龙江省和吉林省,春夏季为发病高峰期,50~59岁年龄组、农民及家务待业人员是主要发病群体。

关键词：森林脑炎蜱传脑炎流行特征

Climate change and hydrologic process response in the Tarim River Basin over the past 50 years

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Chinese Science Bulletin 2006年第A1期51卷 25-36页

作者： xu Changchun CHEN yaning LI Weihong CHEN Yapeng Xinjiang Institute of Ecology and Geography Chinese Academy Of Sci ences Urumqi 830011 China

在在过去的 50 年的 Tarim 河盆的气候变化和水疗院逻辑过程反应是越来越多的研究人员的焦点“注意。在这篇论文，温度和降水时间系列被发现介绍单音补品的增加趋势 usingnonparametric 测试。显著地，重要的步在温度和降水时间系列变... 详细信息

在在过去的 50 年的 Tarim 河盆的气候变化和水疗院逻辑过程反应是越来越多的研究人员的焦点“注意。在这篇论文，温度和降水时间系列被发现介绍单音补品的增加趋势 usingnonparametric 测试。显著地，重要的步在温度和降水时间系列变化发生在 1986。由在源流和主流对比自然的水过程的趋势，我们发现它不是人为的活动引起了河的气候变化在 Tarim 的更低的活动范围枯竭了，植被堕落了河。灰色的关联分析的结果证明散布河的更高的纬度的流量更仔细与冬季雪袜子被联系，当更低的纬度的与夏天温度有关仔细是更多时。在源流的流量对降水更敏感，当那对蒸发在主流更敏感时。尽管有降水在过去的 50years 上增加了的事实，增加温度引起的强壮的蒸发削弱了流量到某程度。

关键词：气候变化水资源非参数检验水文过程响应灵敏度

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一种BD2卫星导航信号的捕获方法

桂林电子科技大学学报 2014年第5期34卷 354-358页

作者：苏文剑刘庆华纪元法宁春林徐亚宁桂林电子科技大学信息与通信学院广西桂林541004 国家海洋局第一海洋研究所海气相互作用及气候变化实验室山东青岛266061

针对传统捕获方法无法应用于中国北斗二代的新型无源导航信号,在GPS卫星信号捕获方法的基础上,提出一种BD2卫星信号捕获方法,消除了数据位跳变或NH码翻转导致的相关值变化,提高了BD2卫星信号的捕获效率。测试结果表明,该方法能够有效地... 详细信息

针对传统捕获方法无法应用于中国北斗二代的新型无源导航信号,在GPS卫星信号捕获方法的基础上,提出一种BD2卫星信号捕获方法,消除了数据位跳变或NH码翻转导致的相关值变化,提高了BD2卫星信号的捕获效率。测试结果表明,该方法能够有效地实现BD2卫星信号的捕获。

关键词： BD2 捕获伪码相关

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可必特气雾剂对哮喘患者的支气管扩张作用

药物流行病学杂志 2000年第3期9卷 118-119页

作者：李承红孙怡君林榕徐亚宁沈继奋武汉职工医学院附属医院呼吸内科 430015 武汉职工医学院附属医院药剂科 430015

目的 :探讨吸入可必特气雾剂 (溴化异丙托品与沙丁胺醇混合气雾剂 )及两者单一制剂对哮喘患者的支气管扩张作用。方法 :通过 2 8例哮喘患者先后吸入可必特气雾剂、溴化异丙托品气雾剂 (爱喘乐气雾剂 )和沙丁胺醇气雾剂 (喘乐宁气雾剂 ) ... 详细信息

目的 :探讨吸入可必特气雾剂 (溴化异丙托品与沙丁胺醇混合气雾剂 )及两者单一制剂对哮喘患者的支气管扩张作用。方法 :通过 2 8例哮喘患者先后吸入可必特气雾剂、溴化异丙托品气雾剂 (爱喘乐气雾剂 )和沙丁胺醇气雾剂 (喘乐宁气雾剂 ) ,分别观察吸入后肺功能变化及副作用。结果 :吸入可必特气雾剂在 15 ,30minFEV1的改善情况高于单吸溴化异丙托品气雾剂 (P 0 .0 5 ) ,副作用三者间无明显差异。结论 :可必特气雾剂对气道扩张作用起效快、维持时间长 ,优于单药应用 ,是目前最理想的支气管扩张剂。

关键词：可必特气雾剂哮喘支气管扩张治疗