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Global vulnerability to agricultural drought and its spatial characteristics

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Science China Earth Sciences 2017年第5期60卷 910-920页

作者： WU JianJun GENG GuangPo ZHOU HongKui liu jinghui WANG QianFeng YANG JianHua Key Laboratory of Environmental Change and Natural Disaster Ministry of Education Beijing Normal University Beijing 100875 China State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing 100875 China Faculty of Geographical Science Beijing Normal University Beijing 100875 China Center for Drought and Risk Research Beijing Normal University Beijing 100875 China Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China College of Environment and Resources Fuzhou University Fuzhou 350116 China

As an important part of agricultural drought risk, agricultural drought vulnerability helps effectively prevent and alleviate drought impacts by quantifying the vulnerability as well as identifying its spatial distribution characteristics. In this study, global agricultural cultivation regions were chosen as the study area; six main crops(wheat, maize, rice, barley, soybean,sorghum) were selected as the hazard-affected body of agricultural drought. Then, global vulnerability to agricultural drought was assessed at a 0.5° resolution and finally, its distribution characteristics were revealed. The results indicated that the area percentages of different grades of global vulnerability to agricultural drought from low to very high were 38.96%, 28.41%,25.37%, and 7.26%, respectively. This means that the total area percentage of high and very high vulnerability zones exceeded30% of the study area. Although high and very high vulnerability zones were mainly distributed in arid and semi-arid regions,approximately 40% of those above were distributed in humid and semi-humid regions. In addition, only about 15% of the population in this study was located in the high vulnerability regions. Among the vulnerability factors, water deficit during the growing season and the irrigation area ratio are the key factors affecting regional vulnerability. Therefore, the vulnerability could be reduced by adjusting crop planting dates and structures as well as by improving irrigation level and capacity.

关键词： Drought Vulnerability Agriculture Spatial distribution Globe

Impact of Meteorological Drought on Streamflow Drought in Jinghe River Basin of China

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Chinese Geographical Science 2014年第6期24卷 694-705页

作者： ZHAO Lin LYU Aifeng WU Jianjun Michael HAYES TANG Zhenghong HE Bin liu jinghui liu Ming School of Resource and Environmental Sciences Wuhan University Institute of Geographical Sciences and Natural Resources Research Chinese Academy of Sciences Academy of Disaster Reduction and Emergency Management Beijing Normal University National Drought Mitigation Center School of Natural resourcesUniversity of Nebraska-Lincoln Lincoln 68588USA College of Architecture University of Nebraska-Lincoln Lincoln68588USA College of Global Change and Earth System Beijing Normal University

Under global climate change, drought has become one of the most serious natural hazards, affecting the ecological environment and human life. Drought can be categorized as meteorological, agricultural, hydrological or socio-economic drought. Among the different categories of drought, hydrological drought, especially streamflow drought, has been given more attention by local governments, researchers and the public in recent years. Identifying the occurrence of streamflow drought and issuing early warning can provide timely information for effective water resources management. In this study, streamflow drought is detected by using the Standardized Runoff Index, whereas meteorological drought is detected by the Standardized Precipitation Index. Comparative analyses of frequency, magnitude, onset and duration are conducted to identify the impact of meteorological drought on streamflow drought. This study focuses on the Jinghe River Basin in Northwest China, mainly providing the following findings. 1) Eleven meteorological droughts and six streamflow droughts were indicated during 1970 and 1990 after pooling using Inter-event time and volume Criterion method. 2) Streamflow drought in the Jinghe River Basin lagged meteorological drought for about 127 days. 3) The frequency of streamflow drought in Jinghe River Basin was less than meteorological drought. However, the average duration of streamflow drought is longer. 4) The magnitude of streamflow drought is greater than meteorological drought. These results not only play an important theoretical role in understanding relationships between different drought categories, but also have practical implications for streamflow drought mitigation and regional water resources management.

关键词： streamflow drought meteorological drought Standardized Precipitation Index (SPI) Standardized Runoff Index (SRI) timelag Jinghe River Basin

Comparative studies on histological and ultra-structure of the pituitary of different ploidy level fishes

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Science China(Life Sciences) 2006年第5期49卷 446-453页

作者： LONG Yu liu Shaojun HUANG Weiren ZHANG Jian SUN Yuandong ZHANG Chun CHEN Song liu jinghui liu Yun College of Life Sciences Hunan Normal UniversityChangsha 410081China

The histological and ultra-structure of the pituitary in diploid red crucian carp(Carassius auratus red var.),triploid crucian carp and allotetraploid hybrids within and after the breeding season were comparatively *** result showed that there were six endocrine cell types in the pituitary of these three kinds of fishes,and there was an obvious difference in cell size among different ploidy level *** for the same type of pituitary cells,the cell size was increased gradually with the in-creasing ploidy *** the breeding season,the allotetraploid hybrids had higher proportion of go-nadotropin cells(GTH)than triploids,and the triploids had higher proportion of GTH than *** results were related to the earlier sexual maturity of allotetraploid hybrids and sterility of triploid cru-cian *** the other hand,among the three kinds of fishes,the proportion of somatotropin(STH)cells in triploids crucian carp was the highest,whereas that in allotetraploid hybrids was the *** results might be connected with the faster growth rate of triploids and slower growth rate of al-lotetraploid *** addition,in GTH cells of meso-adenohypophysis after the breeding season,there were many endocrine particles in triploids,while those endocrine particles were released from the cells in allotetraploids and *** result showed that the sterility of triploid crucian carp might be related to the hormone which was not released from the GTH *** a word,the present study indicated that the differences in the structure of pituitary among different ploidy level fishes contributed to their difference in the growth rate and gonadal development.

关键词： diploid triploid ailotetraploid pituitary histological structure ultra-structure

基于FTA-AHP的铁路安全风险综合评估方法

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中国铁道科学 2017年第2期38卷 138-144页

作者：刘敬辉中国铁道科学研究院铁道科学技术研究发展中心北京100081

针对单独应用故障树分析法(FTA)或者层次分析法(AHP)进行安全风险评估存在评估结果片面的问题,将FTA方法与AHP方法相结合,研究设计基于FTA-AHP的铁路安全风险综合评估方法。用FTA方法确定目标风险事件的原因事件,构建FTA模型;对FTA模型... 详细信息

针对单独应用故障树分析法(FTA)或者层次分析法(AHP)进行安全风险评估存在评估结果片面的问题,将FTA方法与AHP方法相结合,研究设计基于FTA-AHP的铁路安全风险综合评估方法。用FTA方法确定目标风险事件的原因事件,构建FTA模型;对FTA模型中的基本原因事件分类归纳,建立AHP模型;对AHP模型准则层和指标层因素的重要性进行两两比较,构建各层的判断矩阵;将通过一致性检验的各层判断矩阵中的特征向量作为该层对应因素的权重向量,并结合因素的安全状态评分,得到上一层对应因素的安全状态评分;通过逐层计算各因素的安全状态评分,最终实现对分析目标安全风险的综合评估。以高速列车制动系统的安全风险综合评估为例,验证了方法的可行性和有效性。该方法既可以分析导致铁路系统故障的原因及其影响程度,又可以对整体系统的安全状态进行综合评估,更全面反映系统的安全风险状态。

关键词：铁路系统故障树分析层次分析安全风险综合评估

The Impact of Carbon Emissions on Asset Values and Operating Cash Flows： Evidence From Australian Listed Companies

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Journal of Modern Accounting and Auditing 2013年第1期9卷 94-111页

作者： Li Yongqing Ian Eddie liu jinghui Southern Cross University New South Wales Australia

In November 2011, the Australian government approved the legislation （Clean Energy Act 2011） to introduce a reduction plan of carbon emissions in Australia. This plan will be implemented from July 2012. This is one of the first accounting studies to investigate the potential impacts of this plan on long-lived asset values and operating cash flows for Australian listed companies. A sample of Australian Securities Exchange （ASX） 200 indexed companies from 2＇006 to 2010 is used. Hypotheses are tested based on Heckman＇s （1979） two-stage approach. Three regression models are developed to examine the association between carbon emissions and asset values/operating cash flows. This study finds that asset values and operating cash flows will be adversely affected, if the reduction plan is implemented. Specifically, this study finds that the book value of long-lived assets will decrease, if listed companies are considered to be emissions-liable. The book value of long-lived assets is further found to be negatively associated with listed companies＇ carbon emission levels. This study also demonstrates that operating cash flows of emissions-liable companies will be adversely affected. However, this study does not find a relationship between operating cash flows and companies＇ emission levels. The empirical findings from Australian listed companies provide the evidence that the reduction plan of carbon emissions will adversely affect corporate entities＇ asset values and operating cash flows. The results further indicate that the magnitude of the impact will be proportional to the companies＇ emission levels. The implications of these empirical findings for listed companies, for the accounting profession, and for carbon emission regulators are also discussed.

关键词： carbon emissions reduction asset values operating cash flows Australia

Identification of a common brain network associated with lesional epilepsy

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Acta Epileptologica 2023年第4期6卷 280-282页

作者： Di Wu jinghui liu Liankun Ren Department of Neurology Clinical Center for EpilepsyXuanwu HospitalCapital Medical UniversityNO.45 Changchun StreetBeijing100053Xicheng DistrictChina National Center for Neurological Disorders Beijing100053China Chinese Institute for Brain Research Beijing100053China

Stroke is the leading cause of neurological diseases ***,epilepsy is a common complication of stroke,which greatly impairs the quality of life of patients and poses a significant clinical ***,a better understanding of the risk factors for poststroke epilepsy is crucial.A recent study published in JAMA Neurology studied the brain network associated with poststroke epilepsy in a group of 76 patients compared to a cohort of 625 control patients using lesion mapping *** results showed that negative functional connectivity between lesion locations and regions in the basal ganglia and cerebellum confers a higher risk of developing epilepsy after *** lesion network nodes associated with epilepsy were identical across different lesion types including hematomas,traumas,tumors,and ***,the poststroke epilepsy brain network has potential therapeutic relevance to deep brain stimulation(DBS).In a cohort of 30 patients,the functional connectivity between anterior thalamic DBS sites and the lesion network nodes was found to correlate with seizure control after *** summary,the finding provides a novel method for predicting the risk of poststroke epilepsy in patients and may guide brain stimulation treatments for epilepsy.

关键词： Poststroke epilepsy Lesion network mapping Brain network Neuromodulation

防排水系统对复合式衬砌渗透特性的影响及表征方法

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同济大学学报（自然科学版） 2021年第7期49卷 995-1003页

作者：李晓军刘荆辉同济大学土木工程学院上海200092

采用修正的初衬渗透系数表征复合式衬砌的渗透特性。建立了复合式衬砌渗流模型,推导了复合式衬砌的渗透系数计算公式,并分别采用模型退化方法和数值法对提出的公式进行了验证。结果表明:当围岩渗透系数为1×10^(-7)~1×10^(-6)m·s^(-1)... 详细信息

采用修正的初衬渗透系数表征复合式衬砌的渗透特性。建立了复合式衬砌渗流模型,推导了复合式衬砌的渗透系数计算公式,并分别采用模型退化方法和数值法对提出的公式进行了验证。结果表明:当围岩渗透系数为1×10^(-7)~1×10^(-6)m·s^(-1)时,考虑环向排水管、土工布和防水板的复合式衬砌渗透系数对涌水量和外水压力的影响不容忽视;复合式衬砌渗透系数与环向排水管间距、初衬渗透系数、初衬内外半径、土工布厚度、土工布渗透系数密切相关;环向排水管间距越大,复合式衬砌渗透系数越小。

关键词：岩石隧道复合式衬砌渗透系数土工布排水管

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改革开放以来我国报业的扩张路径

武汉大学学报（人文科学版） 2008年第6期61卷 793-796页

作者：刘静慧武汉大学新闻与传播学院湖北武汉430072

改革开放以来,我国报业的扩张路径主要呈现为:报业结构由单一走向多元;报业经营由事业单位转向企业化经营再到产业化运作;报业主体由报社变为报业集团再为传媒集团;报业发行模式由邮发合一到自办发行再到多种发行模式并存;报业技术由传... 详细信息

改革开放以来,我国报业的扩张路径主要呈现为:报业结构由单一走向多元;报业经营由事业单位转向企业化经营再到产业化运作;报业主体由报社变为报业集团再为传媒集团;报业发行模式由邮发合一到自办发行再到多种发行模式并存;报业技术由传统迈向现代进而网络化数字化。

关键词：报业结构报业经营报业发行模式报业技术

文旅融合时代公共图书馆研学旅行服务模式与路径研究

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国家图书馆学刊 2021年第1期30卷 38-43页

作者：刘景会江西省图书馆

在文旅融合背景下,公共图书馆开展研学旅行服务是其拓展社会教育功能的一种渠道,更是深化图书馆服务的一种创新。文章在分析公共图书馆研学旅行服务的驱动因素的基础上,梳理了公共图书馆研学旅行服务的相关实践,将其服务模式归纳为研学... 详细信息

在文旅融合背景下,公共图书馆开展研学旅行服务是其拓展社会教育功能的一种渠道,更是深化图书馆服务的一种创新。文章在分析公共图书馆研学旅行服务的驱动因素的基础上,梳理了公共图书馆研学旅行服务的相关实践,将其服务模式归纳为研学目的地模式和"阅读+"模式两种,并从做好顶层设计、强化服务功能、构建多元主体协同、拓展营销渠道等方面提出公共图书馆研学旅行服务的发展路径。参考文献15。

关键词：研学旅行文旅融合公共图书馆