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Prevalence of vegetation browning in China’s drylands under climate change 被引量:1
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作者 Li Fu Guolong Zhang +3 位作者 Jianping Huang Ming Peng Lei Ding Dongliang Han 《Geography and Sustainability》 CSCD 2024年第3期405-414,共10页
Vegetation greening has long been acknowledged,but recent studies have pointed out that vegetation greening is possibly stalled or even reversed.However,detailed analyses about greening reversal or increased browning ... Vegetation greening has long been acknowledged,but recent studies have pointed out that vegetation greening is possibly stalled or even reversed.However,detailed analyses about greening reversal or increased browning of vegetation remain scarce.In this study,we utilized the normalized difference vegetation index(NDVI)as an indicator of vegetation to investigate the trends of vegetation greening and browning(monotonic,interruption,and reversal)through the breaks for the additive season and trend(BFAST)method across China’s drylands from 1982 to 2022.It also reveals the impacts of ecological restoration programs(ERPs)and climate change on these vegetation trends.We find that the vegetation displays an obvious pattern of east-greening and west-browning in China’s drylands.Greening trends mainly exhibits monotonic greening(29.8%)and greening with setback(36.8%),whereas browning shows a greening to browning reversal(19.2%).The increase rate of greening to browning reversal is 0.0342/yr,which is apparently greater than that of greening with setback,0.0078/yr.This research highlights that,under the background of widespread vegetation greening,vegetation browning is pro-gressively increasing due to the effects of climate change.Furthermore,the ERPs have significantly increased vegetation coverage,with the increase rate in 2000-2022 being twice as much as that of 1982-1999 in reveg-etation regions.Vegetation browning in southwestern Qingzang Plateau is primarily driven by adverse climatic factors and anthropogenic disturbances,which offset the efforts of ERPs. 展开更多
关键词 China’s drylands Ecological restoration programs Climate change Greening to browning reversal BFAsT
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An Improved Coupled Level Set and Continuous Moment-of-Fluid Method for Simulating Multiphase Flows with Phase Change
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作者 Zhouteng Ye Cody Estebe +8 位作者 Yang Liu Mehdi Vahab Zeyu Huang Mark Sussman Alireza Moradikazerouni Kourosh Shoele Yongsheng Lian Mitsuhiro Ohta M.Yousuff Hussaini 《Communications on Applied Mathematics and Computation》 EI 2024年第2期1034-1069,共36页
An improved algorithm for computing multiphase flows is presented in which the multimaterial Moment-of-Fluid(MOF)algorithm for multiphase flows,initially described by Li et al.(2015),is enhanced addressing existing MO... An improved algorithm for computing multiphase flows is presented in which the multimaterial Moment-of-Fluid(MOF)algorithm for multiphase flows,initially described by Li et al.(2015),is enhanced addressing existing MOF difficulties in computing solutions to problems in which surface tension forces are crucial for understanding salient flow mechanisms.The Continuous MOF(CMOF)method is motivated in this article.The CMOF reconstruction method inherently removes the"checkerboard instability"that persists when using the MOF method on surface tension driven multiphase(multimaterial)flows.The CMOF reconstruction algorithm is accelerated by coupling the CMOF method to the level set method and coupling the CMOF method to a decision tree machine learning(ML)algorithm.Multiphase flow examples are shown in the two-dimensional(2D),three-dimensional(3D)axisymmetric"RZ",and 3D coordinate systems.Examples include two material and three material multiphase flows:bubble formation,the impingement of a liquid jet on a gas bubble in a cryogenic fuel tank,freezing,and liquid lens dynamics. 展开更多
关键词 Moment-of-Fluid(MOF) surface tension Two phase flow Phase change Deforming boundaries with change(s)in topology Two-dimensional(2D) Three-dimensional(3D)axisymmetric 3D
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A Systematic Literature Review of the Impact of Climate Change on Menopause: Altering the Age, Severity of Symptoms and Long-Term Effects
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作者 Vaidehi Chauhan Sameena Rahman 《Open Journal of Obstetrics and Gynecology》 2024年第7期1018-1026,共9页
Objective: This systematic review investigates the impact of climate change on menopause, focusing on the correlation between geographical location—considering altitude, temperature, humidity, and annual temperature ... Objective: This systematic review investigates the impact of climate change on menopause, focusing on the correlation between geographical location—considering altitude, temperature, humidity, and annual temperature range—and women’s menopausal experiences. This study aims to interpret how these environmental factors influence the age of onset, severity of symptoms such as hot flushes and night sweats, and other long-term effects of menopause. Understanding these relationships addresses a significant gap in current knowledge and could guide future public health strategies. Methods: Through a comprehensive analysis of three cross-continental studies involving 1500 postmenopausal women from Spain, South American countries (Ecuador, Panama, Chile), various climates in Türkiye (Black Sea, Mediterranean, Continental), and the United Arab Emirates (UAE), this review evaluates diverse environmental impacts. Studies were selected based on their methodological rigor, geographical diversity, and focus on the unique and personal experiences of menopause. Data was collected via questionnaires and routine medical checkups, analyzing demographic, lifestyle, mood, symptom severity, and onset age variables. Results: Preliminary analysis indicates that 52.5% of participants from Spanish-speaking countries and the UAE reported vasomotor symptoms, with those in higher temperatures and lower altitudes experiencing exacerbated symptoms. Notably, Mediterranean climates were associated with an earlier menopause onset. Seasonal changes had minimal impact across all regions, suggesting lifestyle and other environmental factors play a more significant role. Conclusions: The findings highlight a clear link between climate-related geographical factors and the menopausal experience. Women in warmer, lower-altitude regions suffer more severe symptoms, while those in Mediterranean climates face earlier onset. The absence of significant seasonal variations across the studies underscores the predominance of lifestyle and environmental factors over purely climatic conditions. These insights pave the way for targeted interventions and support the need for further public health research into the complex interactions between climate change and menopause. 展开更多
关键词 MENOPAUsE Climate change Women’s Health PERIMENOPAUsE
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The Cultural Implication of Brick Carving Model Calligraphy in Shanxi Chang's Manor
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作者 潘冬梅 冯涛 《Journal of Landscape Research》 2009年第11期63-67,共5页
Focusing on the unique style of brick carving model calligraphy in Shanxi Chang's manor,this research analyses the content and feature of the different parts of brick carving,and discuses the presenting cultural d... Focusing on the unique style of brick carving model calligraphy in Shanxi Chang's manor,this research analyses the content and feature of the different parts of brick carving,and discuses the presenting cultural deposits.It reflects the deep Confucian culture of Shanxi Chang's manor,with the peculiar charming in culture and aesthetic value. 展开更多
关键词 The chang’s MANOR MODEL CALLIGRAPHY BRICK CARVING Chinese traditional culture
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S型异质结光催化剂ZnFe_(2)O_(4)/WO_(3)的构筑及光催化还原CO_(2)性能 被引量:1
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作者 刘平 朱成才 +1 位作者 李艳阳 要红昌 《无机化学学报》 SCIE CSCD 北大核心 2024年第1期197-208,共12页
通过在WO_(3)纳米片表面负载ZnFe_(2)O_(4)纳米颗粒,构建了一系列S型异质结光催化剂ZnFe_(2)O_(4)/WO_(3),并研究了其光催化CO_(2)还原性能。在没有助催化剂和牺牲剂的条件下,所制备的ZnFe_(2)O_(4)/WO_(3)复合材料可对CO_(2)与水蒸汽... 通过在WO_(3)纳米片表面负载ZnFe_(2)O_(4)纳米颗粒,构建了一系列S型异质结光催化剂ZnFe_(2)O_(4)/WO_(3),并研究了其光催化CO_(2)还原性能。在没有助催化剂和牺牲剂的条件下,所制备的ZnFe_(2)O_(4)/WO_(3)复合材料可对CO_(2)与水蒸汽进行光催化反应。优化后的材料光照5 h后CO_(2)还原产物CO和CH_(4)的产量分别为7.87和4.88μmol·g^(-1)。相对于单相组分,CO和CH_(4)的产量明显提高。光催化活性的提高,归因于ZnFe_(2)O_(4)和WO_(3)异质结的形成以及光生载流子的S型电荷传输模式。 展开更多
关键词 CO_(2)还原 光催化活性 ZnFe_(2)O_(4)/WO_(3) 异质结 s型电荷传输模式
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pHSP70P-EGFP真核表达载体的构建及其在人Chang's肝细胞中的表达
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作者 高峰 陈亚军 杨学文 《临床检验杂志》 CAS CSCD 北大核心 2011年第6期444-447,共4页
目的构建HSP70启动子与绿色荧光蛋白重组真核表达载体,并在人Chang's肝细胞表达,建立一种新的体外药物肝毒性早期预测细胞模型。方法提取人Chang's肝细胞基因组DNA,钓取HSP70启动子基因,构建重组载体,经脂质体转染人Chang'... 目的构建HSP70启动子与绿色荧光蛋白重组真核表达载体,并在人Chang's肝细胞表达,建立一种新的体外药物肝毒性早期预测细胞模型。方法提取人Chang's肝细胞基因组DNA,钓取HSP70启动子基因,构建重组载体,经脂质体转染人Chang's肝细胞,用G418筛选稳定转染细胞,用荧光显微镜观察绿色荧光表达情况,用实时荧光定量PCR检测EGFP基因表达量的变化。结果成功钓取HSP70启动子基因并导入真核表达载体pEGFP-N1;G418以300 ng/mL的终浓度筛选出稳定转染的单克隆细胞;荧光显微镜观察到肝毒性药物酮康唑刺激人Chang's肝细胞后,可诱导HSP70启动子调控增强型绿色荧光蛋白发出绿色荧光,药物刺激组EGFP mRNA相对表达量与正常对照组比较有统计学意义(t=-14.21,P<0.05)。结论成功构建HSP70启动子与绿色荧光蛋白共表达真核表达载体,获得稳定转染单克隆细胞,并证实HSP70在肝毒性药物刺激下的应激表达,为建立新的体外药物肝毒性早期预测细胞模型进行高通量筛选新药奠定了基础。 展开更多
关键词 热激蛋白 启动子 chang's肝细胞 基因重组
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Landuse/landcover changes in Zhangye oasis of Hexi Corridor 被引量:9
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作者 MENG Jijun,WU Xiuqin,LI Zhengguo(Department of Urban and Environmental Scien ce, Peking University, Laboratory of Analysis and Simulation of Earth Surface P rocesses, the Ministry of Education, Beijing 100871, China) 《Journal of Geographical Sciences》 SCIE CSCD 2003年第1期71-75,共5页
Taking two f alse color composite Landsat 5 TM (Thematic Mapper) images of band 4,3,2 taken in 1995 and 2000 as data resources, this paper carried out study on LUCC of Zhan gye oasis in recent five years by interpreta... Taking two f alse color composite Landsat 5 TM (Thematic Mapper) images of band 4,3,2 taken in 1995 and 2000 as data resources, this paper carried out study on LUCC of Zhan gye oasis in recent five years by interpretation according to land reso urces classification system of 1:100,000 Resources and Environmental Data base of the Chinese Academy of Sciences. The results show that great changes have taken place in landuse/landcover in Zhangye oasis since 1 995: (1) Changes of landuse structure show that cropland and land for urban c onstruction and built-up area increased, on the contrary, water area an d grassland decreased. These changes reflect the deterioration of eco-e nvironment and the acceleration of urbanization, and also indicate the problems existing in the arrangement of water and land resources betw een the upper and lower reaches of the Heihe River. (2) Regional diff erences of landuse/landcover are evident, characterized by following asp ects: in Sunan County located in Qilian Mountain area, unused land an d grassland decreased, but cropland and land for urban construction an d built-up area increased. In Minle and Shandan counties located in f oothills, unused land, water area and cropland decreased, but grassland and land for urban construction and built-up area increased. In Zhan gye City, Linze County and Gaotai County located in plain area of th e middle reaches of the Heihe River, unused land, water area and gra ssland decreased, while woodland, cropland and land for urban construction and built-up area increased. 展开更多
关键词 landuse/landcover changes (LUCC) Zhangye oasi s Hexi Corridor
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Relationships of climate change and tree ring of Betula ermanii tree line forest in Changbai Mountain 被引量:34
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作者 YU Da-pao GU Hui-yan +2 位作者 WANG Jian-dong WANG Qing-li DAI Li-min 《Journal of Forestry Research》 SCIE CAS CSCD 2005年第3期187-192,共6页
Based on the tree-ring growth characteristics of Erman's birch (Betula ermanii charm.) and the relationships between it and climatic )'actors at elevation of 1950m, the sensitivity of tree lines in Changbai Mount... Based on the tree-ring growth characteristics of Erman's birch (Betula ermanii charm.) and the relationships between it and climatic )'actors at elevation of 1950m, the sensitivity of tree lines in Changbai Mountain to climatic factors was assessed. The results indicated tree line forest in Changbai Mountain had an obvious sensitivity to climate factors. However, difference from other study sits is that the main climatic control factor on tree-ring growth was not current growth season temperatures, as might be expected, but previous winter and current March temperature. Although the precipitation in the region was quite abundant, the tree-ring growth was still significantly correlated with the precipitation during previous winter and current spring. Additionally, climatic factors which influenced the Erman's birch growth were not the yearly variables, but seasonal and monthly variables. Therefore, the reported increase in yearly mean temperature and total yearly precipitation since 1980s was not responded by sustained increase in ring widths in recent decades. 展开更多
关键词 Climatic change dendrochronology Erman's birch Tree line in changbai Mountain
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Global glaciations and atmospheric change at ca.2.3 Ga 被引量:19
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作者 Haoshu Tang Yanjing Chen 《Geoscience Frontiers》 SCIE CAS CSCD 2013年第5期583-596,共14页
This paper compiles lithostratigraphic and geochronological data obtained for the Palaeoproterozoic glacial diamictite-bearing successions,and thereby provides insights into understanding the geological processes caus... This paper compiles lithostratigraphic and geochronological data obtained for the Palaeoproterozoic glacial diamictite-bearing successions,and thereby provides insights into understanding the geological processes causing the Huronian Glaciation Event.The majority of evidence for appearances of this glaciation event can be related to the Kenorland supercontinent breakup,allied to significant atmospheric change,as well as blooms of biogeochemical oxygenic photosynthesis.In this paper,the Huronian Glaciation Event is constrained to have occurred synchronously during 2.29-2.25 Ga,accompanied by dramatic environmental changes characteristic of the Great Oxidation Event which includes the pre- 2.3 Ga hydrosphere oxidation and the post-2.3 Ga atmosphere oxygenation. 展开更多
关键词 Global glaciation Earth’s environmental change Great Oxidation Event LITHOsTRATIGRAPHY GEOCHRONOLOGY
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The withdrawal of the U.S. from the Paris Agreement and its impact on global climate change governance 被引量:5
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作者 ZHANG Yong-Xiang CHAO Qing-Chen +1 位作者 ZHENG Qiu-Hong HUANG Lei 《Advances in Climate Change Research》 SCIE CSCD 2017年第4期213-219,共7页
The global community has prepared for the withdrawal of the U.S. from the Paris Agreement since Donald Trump was elected as the president of the U.S. However, Trump's formal declaration of withdrawal still caused ... The global community has prepared for the withdrawal of the U.S. from the Paris Agreement since Donald Trump was elected as the president of the U.S. However, Trump's formal declaration of withdrawal still caused worldwide reaction. Trump will use the withdrawal to build his political reputation and to renegotiate the Paris Agreement despite its negative effects on the political credibility, international relationships, and potential long-term economic growth of the U.S. In general, the withdrawal of the U.S. from the Paris Agreement will not change the development of low-carbon technologies and the transformation trend of the global climate governance regime. However, the long-term goals and international cooperation on climate change will be affected by budget cuts in American climate change research and the cancelation of donations from the multilateral environmental fund of the U.S. If the Paris Agreement is renegotiated, the common but differentiated principle of responsibility of the United Nations Framework Convention on Climate Change will be challenged again. Nevertheless, climate change governance remains a main theme of future sustainable development. Instead of national governments, local governments and non-governmental organizations will develop strategies for technical innovation and emphasize pragmatic cooperation, thus expanding their roles in climate change governance. The capacity building on climate change research and public awareness should be enhanced as a long-term objective of global climate change governance. 展开更多
关键词 U.s. withdraw PARIs AGREEMENT Global climate change GOVERNANCE IMPACT
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Synchronism of runoff response to climate change in Kaidu River Basin in Xinjiang,Northwest China 被引量:2
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作者 Jie Xue 《Research in Cold and Arid Regions》 CSCD 2016年第1期82-94,共13页
The runoff in alpine river basins where the runoff is formed in nearby mountainous areas is mainly affected by temperature and precipitation. Based on observed annual mean temperature, annual precipitation, and runoff... The runoff in alpine river basins where the runoff is formed in nearby mountainous areas is mainly affected by temperature and precipitation. Based on observed annual mean temperature, annual precipitation, and runoff time-series datasets during 1958-2012 within the Kaidu River Basin, the synchronism of runoff response to climate change was analyzed and iden- tified by applying several classic methods, including standardization methods, Kendall's W test, the sequential version of the Mann-Kendall test, wavelet power spectrum analysis, and the rescaled range (R/S) approach. The concordance of the nonlinear trend variations of the annual mean temperature, annual precipitation, and runoff was tested significantly at the 0.05 level by Kendall's W method. The sequential version of the Mann-Kendall test revealed that abrupt changes in annual runoff were synchronous with those of annual mean temperature. The periodic characteristics of annual runoff were mainly consistent with annual precipitation, having synchronous 3-year significant periods and the same 6-year, 10-year, and 38-year quasi-periodicities. While the periodic characteristics of annual runoff in the Kaidu River Basin tracked well with those of annual precipitation, the abrupt changes in annual runoff were synchronous with the annual mean temperature, which directly drives glacier- and snow-melt processes. R/S analysis indicated that the annual mean temperature, annual precipitation, and runoff will continue to increase and remain synchronously persistent in the future. This work can improve the understanding of runoff response to regional climate change to provide a viable reference in the management of water resources in the Kaidu River Basin, a regional sustainable socio-economie development. 展开更多
关键词 climate change synchronism wavelet power spectrum analysis R/s method RUNOFF
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Property changes of anchor grout calcined ginger nuts admixed with fly ash and quartz sand after accelerated ageing tests 被引量:3
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作者 ZHANG Jing-ke ZHANG Li-xiang +3 位作者 ZHAO Lin-yi LIU Dun GUO Qing-lin PEI Qiang-qiang 《Journal of Central South University》 SCIE EI CAS CSCD 2019年第11期3114-3125,共12页
Calcined ginger nuts admixed by fly ash and quartz sand (CGN-(F+S)) has been validated to be basically compatible to earthen sites as an anchor grout. Accelerated ageing tests including water stability test, temperatu... Calcined ginger nuts admixed by fly ash and quartz sand (CGN-(F+S)) has been validated to be basically compatible to earthen sites as an anchor grout. Accelerated ageing tests including water stability test, temperature and humidity cycling test, soundness test and alkali resistance test are conducted with the objective to further research the property changes of CGN-(F+S) grout. Density, surface hardness, water penetration capacity, water permeability capacity, soluble salt, scanning electron microscopy (SEM) images and energy dispersive spectrometry (EDS) spectrum of these samples have been tested after accelerated ageing tests. The results show that densities of samples decrease, surface hardness, water penetration capacity and water permeability capacity of samples increase generally. Besides, soluble salt analysis, SEM and EDS results well corroborate the changes. Based on the results it can be concluded that property changes are most serious after temperature and humidity cycling test, followed by water stability, soundness and alkali resistance test in sequence. But in general, CGN-(F+S) still has good durability. 展开更多
关键词 CGN-(F%PLUs%s) grout accelerated ageing tests physical property change chemical property change scanning electron microscopy energy dispersive spectrometry
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Streptozotocin induced Alzheimer's disease like changes and the underlying neural degeneration and regeneration mechanism 被引量:7
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作者 Pradip Kumar Kamat 《Neural Regeneration Research》 SCIE CAS CSCD 2015年第7期1050-1052,共3页
Alzheimer’s disease(AD)is a neurodegenerative disorder which is remarkably characterized by pathological hallmarks that include neurofibrillary tangles,neuronal loss extracellular senile plaques containing aggregat... Alzheimer’s disease(AD)is a neurodegenerative disorder which is remarkably characterized by pathological hallmarks that include neurofibrillary tangles,neuronal loss extracellular senile plaques containing aggregated amyloid beta(Aβ),and neurofibrillary tangles composed of the hyperphosphorylated form of the microtubule protein tau.It is the most common form of dementia which is characterized by severe neurodegenerative changes such as loss of neurons and synapses in brain(Kamat et al.,2014). 展开更多
关键词 sTZ streptozotocin induced Alzheimer’s disease like changes and the underlying neural degeneration and regeneration mechanism AD
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Using Airgun Source Signals to Study Regional Wave Velocity Changes before and after the Yunlong M_S5.0 and Yangbi M_S5.1 Earthquakes 被引量:3
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作者 YANG Jianwen LI Lei +4 位作者 ZHANG Pengying YE Beng HE Yingwen CHEN Jia CHA Wenjian 《Earthquake Research in China》 CSCD 2019年第2期320-335,共16页
On the basis of the airgun source signals recorded by the stations from January,2016 to June,2017,we use cross-correlation detection technology to obtain the characteristics of the stable phase travel time change of e... On the basis of the airgun source signals recorded by the stations from January,2016 to June,2017,we use cross-correlation detection technology to obtain the characteristics of the stable phase travel time change of each station.We used the Yunlong MS5.0 and Yangbi MS5.1 earthquakes as samples.According to regional characteristics,13 stations with high signal-to-noise ratios and complete data were selected(including 3 fixed stations and 10 active source stations).They are divided into four regions,and on the basis of the GNSS baseline data,the characteristics of regional wave velocity changes before and after the earthquake are analyzed.The results show that the station phase travel time change and the regional stress characteristics represented by the GNSS baseline data have good correlation in the short-term.Due to different degrees of regional stress,there are differences in the travel time changes of different stations in the four regions.Before the Yunlong MS5.0 and Yangbi MS5.1 earthquakes,with regional stress adjustment,there is an upward trend in the travel time changes of related stations in the adjacent areas of up to 0.02 s.The difference is that there are differences in the time nodes and duration of the travel time anomalies,and there is a reverse descent process after the Yangbi MS5.1 earthquake.There are different degrees of travel time fluctuations in the relevant stations before and after the two earthquakes,but the fluctuation range before and after the earthquake was small.Compared with the water level change of the reservoir,the adjustment of the regional stress is more likely to have a substantial impact on the travel time changes of the relevant stations. 展开更多
关键词 Airgun source CROss-CORRELATION detection TRAVEL time change Yunlong M s5.0 EARTHQUAKE Yangbi M s5.1 EARTHQUAKE
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Climate change impact in the Western Himalaya:people's perception and adaptive strategies 被引量:2
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作者 Vikram S.Negi Rakesh K.Maikhuri +2 位作者 Dalbeer Pharswan Shinny Thakur Pitamber P.Dhyani 《Journal of Mountain Science》 SCIE CSCD 2017年第2期403-416,共14页
The Himalaya represents a vast mountain system and globally valued for its significant role in regulation of global as well as regional climate that has direct impact on biodiversity and ecosystem services crucial for... The Himalaya represents a vast mountain system and globally valued for its significant role in regulation of global as well as regional climate that has direct impact on biodiversity and ecosystem services crucial for sustenance of millions of people in Himalaya and adjoining areas. However, mountain regions worldwide are impacted by climate change and at the same time represent distinctive area for the assessment of climate related impacts. Climate change impacts in Himalayan region have its implications on food production, natural ecosystems,retreat of glacier, water supply, human and animal health and overall human well being. The livelihood and food security of the people inhabited in region largely depend on climate sensitive sectors i.e.agriculture, livestock, forestry and their interlinkages with each other, and has the potential to break down food and nutritional security as well as livelihood support systems. People's perception and understanding of climate can be an important asset when it comes to adaptation to climate change impact;however it is not taken into consideration for the development of policy design and implementation of modern mitigation and adaptation strategies by governments and other civil society organizations.The knowledge of local people and farming communities for rural landscape management and sustainable use of bioresources is gaining credence as a key strategy to cope up with the climate change.Therefore, the present study analyzes the indigenous knowledge of local people and their perceptions on climate change, and also documented adaptation approaches at local level in mountain ecosystem of western Himalaya. The study could be useful to policy makers to design appropriate adaptation strategies to cope up with the impacts of climate change. 展开更多
关键词 Western Himalaya Climate change People's perception Traditional knowledge ADAPTATION
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Methods of extracting change information and updating land use/cover map based on 3S technology 被引量:1
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作者 YANG Gui-jun~(1,2), ZHANG Ji-xian~2, WU Wen-bo~1, ZHAO Hong~1 (1. Liaoning Technical Chiversity, Fuxin, 123000, China 2. Academy of China Surveying and Mapping Science, Beijing 100039, China) 《中国有色金属学会会刊:英文版》 CSCD 2005年第S1期38-41,共4页
A fully automated approach for detecting land use/cover change using remote sensing data, GIS data, GPS data is presented. The integrating raster with vector methods of updating the basic land use/land cover map based... A fully automated approach for detecting land use/cover change using remote sensing data, GIS data, GPS data is presented. The integrating raster with vector methods of updating the basic land use/land cover map based on 3S technology is becoming one of the most important developing directions in 3S application fields, land-use and cover change fields over the world. It has been successful applied in two tasks of the Ministry of Land and Resources of China, and takes some benefit. 展开更多
关键词 3s technology land-use and COVER changE OBJECT-ORIENTED
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Climate Change: Trends and People’s Perception in Nepal 被引量:2
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作者 Rohini P. Devkota 《Journal of Environmental Protection》 2014年第4期255-265,共11页
In the context of climate change, the frequency and intensity of extreme events such as floods and droughts will increase which could put tremendous challenges in water resources management in the coming days. While s... In the context of climate change, the frequency and intensity of extreme events such as floods and droughts will increase which could put tremendous challenges in water resources management in the coming days. While scientific knowledge on climate threats and changing climate patterns are essential, it is also important to consider the impacts in relation to how the threats are perceived and handled by local people. This paper intends to assess the trend and people’s perception on temperature and precipitation. Three focus groups’ discussion and a total number of 240 households were interviewed during field visit. The collected information was scaled from the least preferred-1 to the most preferred-5 based on their preferences. The trend of mean of annual average, maximum and minimum temperature indicates that the temperature has increased significantly and precipitation intensity and magnitude are also in increasing trend in the monsoon and postmonsoon seasons which may raise the extreme flood events. These facts were verified with the people’s perception. This finding could be useful for formulation of effective flood management policy and plan in this river basin as well as very applicable for other similar areas. 展开更多
关键词 CLIMATE changE TRENDs People’s PERCEPTION
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Multifractal analysis of white matter structural changes on 3D magnetic resonance imaging between normal aging and early Alzheimer's disease 被引量:1
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作者 倪黄晶 周泸萍 +3 位作者 曾彭 黄晓林 刘红星 宁新宝 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第7期155-161,共7页
Applications of multifractal analysis to white matter structure changes on magnetic resonance imaging(MRI) have recently received increasing attentions. Although some progresses have been made, there is no evident s... Applications of multifractal analysis to white matter structure changes on magnetic resonance imaging(MRI) have recently received increasing attentions. Although some progresses have been made, there is no evident study on applying multifractal analysis to evaluate the white matter structural changes on MRI for Alzheimer's disease(AD) research. In this paper, to explore multifractal analysis of white matter structural changes on 3D MRI volumes between normal aging and early AD, we not only extend the traditional box-counting multifractal analysis(BCMA) into the 3D case, but also propose a modified integer ratio based BCMA(IRBCMA) algorithm to compensate for the rigid division rule in BCMA. We verify multifractal characteristics in 3D white matter MRI volumes. In addition to the previously well studied multifractal feature,△α, we also demonstrated △ f as an alternative and effective multifractal feature to distinguish NC from AD subjects.Both △α and △ f are found to have strong positive correlation with the clinical MMSE scores with statistical significance.Moreover, the proposed IRBCMA can be an alternative and more accurate algorithm for 3D volume analysis. Our findings highlight the potential usefulness of multifractal analysis, which may contribute to clarify some aspects of the etiology of AD through detection of structural changes in white matter. 展开更多
关键词 MULTIFRACTAL white matter structural change magnetic resonance imaging Alzheimer's disease
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东北地区土地覆被格局变化模拟:基于CLUE-S和Markov-CA模型的对比分析 被引量:3
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作者 王端睿 毛德华 +2 位作者 王宗明 相恒星 冯凯东 《地理科学》 CSSCI CSCD 北大核心 2024年第2期329-339,共11页
研究以遥感解译的东北地区2000年、2010年、2015年的土地覆被变化为基础,充分考虑自然和社会因素对土地覆被变化的影响,分别通过CLUE-S模型和Markov-CA模型对东北地区2015年和2030年土地覆被格局进行模拟,研究结果表明:通过与遥感解译的... 研究以遥感解译的东北地区2000年、2010年、2015年的土地覆被变化为基础,充分考虑自然和社会因素对土地覆被变化的影响,分别通过CLUE-S模型和Markov-CA模型对东北地区2015年和2030年土地覆被格局进行模拟,研究结果表明:通过与遥感解译的2015年实际土地覆被类型数据对比验证,CLUE-S模型和Markov-CA模型模拟结果的总体Kappa指数分别为0.9700和0.9649,结果表明2种模型的模拟结果较为理想,CLUE-S模型的模拟精度较Markov-CA模型更高。2015—2030年东北地区草地、耕地、湿地、其他用地和水体面积呈现下降趋势,林地、人工表面面积呈现增加趋势,人地关系越发紧张。东北地区作为生态环境相对脆弱的区域需警惕不可持续的土地覆被变化,需权衡生态保护、粮食增加与基础设施建设的用地需求和协调发展。 展开更多
关键词 CLUE-s模型 Markov-CA模型 土地利用/覆被变化 空间模拟 东北地区
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Change of Flood Patterns in China under the Influences of Climate Change and Human Activities 被引量:2
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作者 Yin Yixing Xu Youpeng Chen Ying 《Chinese Journal of Population,Resources and Environment》 2009年第3期67-71,共5页
Based on the flood affected area (FA) data of the provinces in China from 1950 to 2005, the article discusses the change of the flood patterns in China, and investigates its relationship with climate change and huma... Based on the flood affected area (FA) data of the provinces in China from 1950 to 2005, the article discusses the change of the flood patterns in China, and investigates its relationship with climate change and human activities. The flood center shifted from North China and the Yangtze-Huaihe basin in the 1950s towards the south, north and west of China, and located in the south of the Yangtze River and South China after the 1990s. The FA in the western provinces was continuously on the rise since the 1950s. There are two characteristics for the future flood pattem in China. The pattern of "flood in the south and drought in the north" depends on the north-south shift of the maximum rainfall region in eastern China. The flood intensification to the west of Hu Huanyong's line mainly results from the increase of rainfall, extreme precipitation and the melting of glaciers under the background of human activity magnification. 展开更多
关键词 flood pattern flood in the south and drought in the north Hu Huanyong's line climate change human activity
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