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Changes in Spring Snow Cover over the Eastern and Western Tibetan Plateau and Their Associated Mechanism
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作者 Fangchi LIU Xiaojing JIA Wei DONG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期959-973,共15页
The spring snow cover(SC)over the western Tibetan Plateau(TP)(TPSC)(W_TPSC)and eastern TPSC(E_TPSC)have displayed remarkable decreasing and increasing trends,respectively,during 1985–2020.The current work investigate... The spring snow cover(SC)over the western Tibetan Plateau(TP)(TPSC)(W_TPSC)and eastern TPSC(E_TPSC)have displayed remarkable decreasing and increasing trends,respectively,during 1985–2020.The current work investigates the possible mechanisms accounting for these distinct TPSC changes.Our results indicate that the decrease in W_TPSC is primarily attributed to rising temperatures,while the increase in E_TPSC is closely linked to enhanced precipitation.Local circulation analysis shows that the essential system responsible for the TPSC changes is a significant anticyclonic system centered over the northwestern TP.The anomalous descending motion and adiabatic heating linked to this anticyclone leads to warmer temperatures and consequent snowmelt over the western TP.Conversely,anomalous easterly winds along the southern flank of this anticyclone serve to transport additional moisture from the North Pacific,leading to an increase in snowfall over the eastern TP.Further analysis reveals that the anomalous anticyclone is associated with an atmospheric wave pattern that originates from upstream regions.Springtime warming of the subtropical North Atlantic(NA)sea surface temperature(SST)induces an atmospheric pattern resembling a wave train that travels eastward across the Eurasian continent before reaching the TP.Furthermore,the decline in winter sea ice(SIC)over the Barents Sea exerts a persistent warming influence on the atmosphere,inducing an anomalous atmospheric circulation that propagates southeastward and strengthens the northwest TP anticyclone in spring.Additionally,an enhancement of subtropical stationary waves has resulted in significant increases in easterly moisture fluxes over the coastal areas of East Asia,which further promotes more snowfall over eastern TP. 展开更多
关键词 snow cover Tibetan Plateau long-term changes spring
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Leading Pattern of Spring Drought Variability over East Asia and Associated Drivers
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作者 赵庆红 杨崧 +1 位作者 田红瑛 邓开强 《Journal of Tropical Meteorology》 SCIE 2024年第1期1-10,共10页
Drought events have become more frequent and intense over East Asia in recent decades,leading to huge socioeconomic impacts.Although the droughts have been studied extensively by cases or for individual regions,their ... Drought events have become more frequent and intense over East Asia in recent decades,leading to huge socioeconomic impacts.Although the droughts have been studied extensively by cases or for individual regions,their leading variability and associated causes remain unclear.Based on the Standardized Precipitation Evapotranspiration Index(SPEI)and ERA5 reanalysis product from 1979 to 2020,this study evealuates the severity of spring droughts in East Asia and investigates their variations and associated drivers.The results indicate that North China and Mongolia have experienced remarkable trends toward dryness during spring in recent decades,while southwestern China has witnessed an opposite trend toward wetness.The first Empirical Orthogonal Function mode of SPEI variability reveals a similar seesawing pattern,with more severe dryness in northwestern China,Mongolia,North China,South Korea,and Japan but increased wetness in Southwestern China and southeast Asia.Further investigation reveals that the anomalously dry(wet)surface in North(Southwestern)China is significantly associated with anomalously high(low)temperature,less(more)precipitation,and reduced(increased)soil moisture during the previous winter and early spring,regulated by an anomalous anticyclone(cyclone)and thus reduced(increased)water vapor convergence.The spring dry-wet pattern in East Asia is also linked to cold sea surface temperature anomalies in the central-eastern Pacific.The findings of this study have important implications for improving the prediction of spring drought events in East Asia. 展开更多
关键词 DROUGHT leading pattern East Asia spring DRIVERS
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The Roots and Fruits of Chinese Spring Festival
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作者 LI GANG 《China Today》 2024年第2期26-29,共4页
The Chinese New Year-the most important holiday in the country-offers a window into China’s past and present.T RADITIONAL festivals forge a nation’s cultural identity and solidarity.Through opulent customs and celeb... The Chinese New Year-the most important holiday in the country-offers a window into China’s past and present.T RADITIONAL festivals forge a nation’s cultural identity and solidarity.Through opulent customs and celebratory activities,they convey the collective psyche,emotions,and aspirations of a nation.As a key part of Chinese culture,traditional Chinese festivals reinforce the bond among Chinese people and preserve our cultural roots. 展开更多
关键词 spring COLLECTIVE preserve
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THE ROOTS AND FRUITS OF CHINESE SPRING FESTIVAL
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作者 Li Gang 《China Report ASEAN》 2024年第2期76-78,共3页
Traditional festivals forge a nation’s cultural identity and solidarity.Through opulent customs and celebratory activities,they convey the collective psyche,emotions,and aspirations of a nation.As a key part of Chine... Traditional festivals forge a nation’s cultural identity and solidarity.Through opulent customs and celebratory activities,they convey the collective psyche,emotions,and aspirations of a nation.As a key part of Chinese culture,traditional Chinese festivals reinforce the bond among Chinese people and preserve our cultural roots.Of all Chinese festivals,the Spring Festival is the most important,both culturally and historically. 展开更多
关键词 ROOT spring spring
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Product Development of High Strength and Toughness Spring Flat Steel
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作者 Jianxin Wang Chunhui Zhang 《Frontiers of Metallurgical Industry》 2024年第1期15-18,共4页
With the continuous development of mechanical industry,higher requirements are put forward for the comprehensive properties of spring steel.The chemical composition and production process of spring flat steel are desi... With the continuous development of mechanical industry,higher requirements are put forward for the comprehensive properties of spring steel.The chemical composition and production process of spring flat steel are designed to meet the requirements of high strength and high toughness of spring flat steel,through the test,the product surface quality and internal quality all meet the national standards,the performance indicators to meet user requirements. 展开更多
关键词 spring flat steel mechanical properties high strength high toughness
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Contrasting Regional Responses of Indian Summer Monsoon Rainfall to Exhausted Spring and Concurrently Emerging Summer El Nino Events
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作者 E.K.KRISHNA KUMAR S.ABHILASH +3 位作者 SANKAR SYAM P.VIJAYKUMAR K.R.SANTOSH A.V.SREENATH 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2023年第4期697-710,共14页
The inverse relationship between the warm phase of the El Nino Southern Oscillation(ENSO)and the Indian Summer Monsoon Rainfall(ISMR)is well established.Yet,some El Nino events that occur in the early months of the ye... The inverse relationship between the warm phase of the El Nino Southern Oscillation(ENSO)and the Indian Summer Monsoon Rainfall(ISMR)is well established.Yet,some El Nino events that occur in the early months of the year(boreal spring)transform into a neutral phase before the start of summer,whereas others begin in the boreal summer and persist in a positive phase throughout the summer monsoon season.This study investigates the distinct influences of an exhausted spring El Nino(springtime)and emerging summer El Nino(summertime)on the regional variability of ISMR.The two ENSO categories were formulated based on the time of occurrence of positive SST anomalies over the Nino-3.4 region in the Pacific.The ISMR’s dynamical and thermodynamical responses to such events were investigated using standard metrics such as the Walker and Hadley circulations,vertically integrated moisture flux convergence(VIMFC),wind shear,and upper atmospheric circulation.The monsoon circulation features are remarkably different in response to the exhausted spring El Nino and emerging summer El Nino phases,which distinctly dictate regional rainfall variability.The dynamic and thermodynamic responses reveal that exhausted spring El Nino events favor excess monsoon rainfall over eastern peninsular India and deficit rainfall over the core monsoon regions of central India.In contrast,emerging summer El Nino events negatively impact the seasonal rainfall over the country,except for a few regions along the west coast and northeast India. 展开更多
关键词 exhausted spring El Nino emerging summer El Nino Indian Summer Monsoon Hadley and Walker circulation tropical easterly jet vertical integrated moisture flux convergence
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Three-Point Bending Test and Crack Detection by Acoustic Emission on Different Spring Steel Wires with Different Crystallographic Textures
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作者 Mathias Lorenz Mohammed Salih +4 位作者 Daniela Schwerdt Nowfal Al-Hamdany Emad Maawad Norbert Schell Eckehard Müller 《材料科学与工程(中英文A版)》 2023年第3期53-67,共15页
In the production of compression springs,high forming velocities and grades of deformation during winding and setting may induce cracks that can lead to failure causing risks of an accident and damage.The AE(acoustic ... In the production of compression springs,high forming velocities and grades of deformation during winding and setting may induce cracks that can lead to failure causing risks of an accident and damage.The AE(acoustic emission)technology,a non-destructive monitoring method,can detect acoustic signals reflected from cracks.To establish this method in the production of technical springs,it was necessary,to find out whether the AE signal is influenced by material properties,phase fractions distribution from tempered martensite,retained austenite,and microstructure including crystallographic texture.In addition,it was investigated to what extent the detected AE signal can be useful to separate between an actual crack and other material responses.Within an in-situ three-point bending test with the AE technology,macro-and micro-crack-typical AE signals were detected for five different spring steel wires(SH,VDSiCr,and FDSiCr according to EN-10270-1 and EN-10270-2).The relative energy related to the initiation,propagation,and growth of cracks caused by mechanical stress was measured using a piezoelectric sensor.If a crack AE signal appeared for the first time,the bending tests were stopped immediately.The results show that the frequency spectrum combined with the intensity of the acoustic signals generated during crack growth depends on the material properties and the crystallographic texture.Furthermore,it could be shown that it is possible to differentiate between micro-crack-typical AE signals and other signals that result from different material responses. 展开更多
关键词 Technical springs AE analysis micro-computer tomography TEXTURE
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基于Spring Boot的产教联合体信息平台设计
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作者 刁建忠 许志伟 伍嘉华 《科技创新与应用》 2024年第14期28-31,共4页
该文设计基于B/S架构的联合体信息平台,利用Spring Boot、MyBatis Plus、Vue等优秀框架实现高效的开发,集成Spring Security和JWT令牌机制,完成认证和权限控制。同时整合Redis缓存,将热点资源缓存至内存中,以实现快速查询操作,从而减轻M... 该文设计基于B/S架构的联合体信息平台,利用Spring Boot、MyBatis Plus、Vue等优秀框架实现高效的开发,集成Spring Security和JWT令牌机制,完成认证和权限控制。同时整合Redis缓存,将热点资源缓存至内存中,以实现快速查询操作,从而减轻MySQL数据库的负载压力。该系统稳定、兼容性强,能使联合体成员沟通更方便、信息的发布和维护的效率更高,实现人才共育共享。 展开更多
关键词 spring Boot MyBatis Vue 产教联合体信息平台 B/S架构
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基于Spring Boot+Vue框架的羊场综合 管理系统软件的设计与应用 被引量:3
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作者 姜韶华 常星海 +5 位作者 高云帆 南风 马东 李书琴 陈玉林 张恩平 《家畜生态学报》 北大核心 2024年第3期55-62,共8页
本研究旨在辅助羊场生产数据规范化管理及良种繁育智能科学化应用,采用MySQL数据库及Java、R编程语言,基于Spring Boot+Vue框架设计了一套羊场综合管理系统软件。该系统优化了羊只信息管理、羊场配种方案,实现生产数据可视化,设置预警... 本研究旨在辅助羊场生产数据规范化管理及良种繁育智能科学化应用,采用MySQL数据库及Java、R编程语言,基于Spring Boot+Vue框架设计了一套羊场综合管理系统软件。该系统优化了羊只信息管理、羊场配种方案,实现生产数据可视化,设置预警功能帮助羊场及时掌握羊只产羔时间与生产性能情况;系统设计羊只基本信息管理、生产信息、疫病信息、繁殖信息、药品管理、饲料管理、统计报表与预警、科学育种八个模块。其中,在科学育种管理子模块中,根据羊场育种需求,构建了三种育种值计算模型(BLUP模型、GLMM模型、平均表现型模型),结合种公母羊实际表现,实现种公母羊的等级排序并自动生成近交系数,得到科学合理的配种方案。本系统在陕北某集约化肉羊场、横山区某绒山羊养殖联合育种户、富平县某奶山羊养殖场进行为期半年的实际生产应用,通过跟踪核心群体,完善与优化系统各项功能,为羊场智慧化、数字化育种管理提供了数据平台,同时也为实现智慧羊场的发展增添了新版本1.0。 展开更多
关键词 spring Boot+Vue框架 羊场 信息管理系统 育种
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基于SpringBoot框架的智慧校园管理系统设计与实现
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作者 刘霞 《长江信息通信》 2024年第2期148-150,共3页
随着国家《智慧校园总体框架》的提出,各职业院校纷纷启动了智慧校园的建设,因学校发展实际情况、重视程度、资金投入等不同,智慧校园建设的步伐也不一致。文章分析了智慧校园管理系统需求,提出基于Spring Boot框架,整合MyBatis数据持... 随着国家《智慧校园总体框架》的提出,各职业院校纷纷启动了智慧校园的建设,因学校发展实际情况、重视程度、资金投入等不同,智慧校园建设的步伐也不一致。文章分析了智慧校园管理系统需求,提出基于Spring Boot框架,整合MyBatis数据持久化框架,数据库选择高性能的MySQL,内存数据库采用Redis缓存技术,采用前后端分离模式设计,前端采用Vue.js、Element-UI、Axios来实现前后端数据交互的系统设计方案和实现过程,为智慧校园的建设提供一种可行的方案参考。 展开更多
关键词 spring Boot 智慧校园 管理系统
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基于Vue.js与Spring Boot的教务管理系统设计
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作者 谢振华 《电脑与信息技术》 2024年第4期95-97,101,共4页
随着Web应用开发技术的不断发展,采用传统Web技术开发的教务管理系统越来越难满足实际需求,在此背景下,提出了一种同时基于Vue.js与Spring Boot的教务管理系统设计与实现方案。该系统采用Vue.js框架作为前端开发框架,实现了前台页面的... 随着Web应用开发技术的不断发展,采用传统Web技术开发的教务管理系统越来越难满足实际需求,在此背景下,提出了一种同时基于Vue.js与Spring Boot的教务管理系统设计与实现方案。该系统采用Vue.js框架作为前端开发框架,实现了前台页面的交互和后台数据展示。同时,使用Spring Boot作为后端框架,提供了稳定的数据请求和数据存储功能。阐述了系统的架构设计、技术实现和功能需求设计等方面内容。该设计方案,使系统具有速度快、效率高、稳定性强等优点,带来良好的用户体验,同时能够满足教务管理的需要。采用该架构设计的系统同时也具有很好的可扩展性和可移植性,方便学校进行二次开发和部署。 展开更多
关键词 Vue.js spring Boot 教务管理系统
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Late spring cold reduces grain number at various spike positions by regulating spike growth and assimilate distribution in winter wheat 被引量:3
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作者 Feifei Lin Cheng Li +8 位作者 Bo Xu Jian Chen Anheng Chen Muhammad A.Hassan Binbin Liu Hui Xu Xiang Chen Jianqiang Sun Jincai Li 《The Crop Journal》 SCIE CSCD 2023年第4期1272-1278,共7页
Late spring cold(LSC) occurred in the reproductive period of wheat impairs spike and floret differentiation during the reproductive period,when young spikelets are very cold-sensitive.However,under LSC,the responses o... Late spring cold(LSC) occurred in the reproductive period of wheat impairs spike and floret differentiation during the reproductive period,when young spikelets are very cold-sensitive.However,under LSC,the responses of wheat spikelets at various positions,leaves,and stems and the interactions between them at physiological levels remain unclear.In the present study,two-year treatments at terminal spikelet stage under two temperatures(2 C,-2 C) and durations(1,2,and 3 days) were imposed in an artificial climate chamber to compare the effects of LSC on grain number and yield in the wheat cultivars Yannong 19(YN19,cold-tolerant) and Xinmai 26(XM26,cold-sensitive).The night temperature regimes were designed to reproduce natural temperature variation.LSC delayed plant growth and inhibited spike and floret differentiation,leading to high yield losses in both cultivars.LSC reduced dry matter accumulation(DMA,g) in spikes,stems,and leaves,reducing the DMA ratios of the spike to leaf and spike to stem.Plant cell wall invertase(CWINV) activity increased in upper and basal spikelets in YN19,whereas CWINV increased in middle spikelets in XM26.Under LSC,soluble sugar and glucose were transported and distributed mainly in upper and basal spikelets for glume and rachis development,so that spike development was relatively complete in YN19,whereas the upper and basal spikelets were severely damaged and most of the glumes in middle spikelets were relatively completely developed in XM26,resulting in pollen abortion mainly in upper and basal spikelets.The development of glumes and rachides was influenced and grain number per spike was decreased after LSC,with kernels present mainly in middle spikelets.Overall,reduced total DMA and dry matter partitioning to spikes under LSC results in poor spikelet development,leading to high losses of grain yield. 展开更多
关键词 WHEAT Late spring cold Dry matter accumulation Cell wall invertase Grain number Yield
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Combined QTL mapping,GWAS and transcriptomic analysis revealed a candidate gene associated with the timing of spring bud flush in tea plant(Camellia sinensis) 被引量:2
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作者 Yujie Liu Si Chen +7 位作者 Chenkai Jiang Haoran Liu Junyu Wang Weizhong He Doogyung Moon Jiedan Chen Liang Chen Jianqiang Ma 《Horticulture Research》 SCIE CSCD 2023年第9期275-277,共3页
Dear Editor,The timing of the spring bud f lush(TBF)is a crucial agro-nomic trait for the tea plant,as it strongly influences the yield and economic value of harvested fresh tea leaves.The TBF of tea plant is generall... Dear Editor,The timing of the spring bud f lush(TBF)is a crucial agro-nomic trait for the tea plant,as it strongly influences the yield and economic value of harvested fresh tea leaves.The TBF of tea plant is generally defined as the date when>30%of the growing tender shoots have reached the stage of one bud with one to three leaves,referred as to the stage of one and a bud,two and a bud,and three and a bud,respectively. 展开更多
关键词 spring mapping analysis
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Diversity on the Interannual Variations of Spring Monthly Precipitation in Southern China and the Associated Tropical Sea Surface Temperature Anomalies 被引量:3
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作者 郭如月 潘蔚娟 +2 位作者 柯敏玲 魏维 王子谦 《Journal of Tropical Meteorology》 SCIE 2023年第3期337-346,共10页
There is a continuous and relatively stable rainy period every spring in southern China(SC).This spring precipitation process is a unique weather and climate phenomenon in East Asia.Previously,the variation characteri... There is a continuous and relatively stable rainy period every spring in southern China(SC).This spring precipitation process is a unique weather and climate phenomenon in East Asia.Previously,the variation characteristics and associated mechanisms of this precipitation process have been mostly discussed from the perspective of seasonal mean.Based on the observed and reanalysis datasets from 1982 to 2021,this study investigates the diversity of the interannual variations of monthly precipitation in spring in SC,and focuses on the potential influence of the tropical sea surface temperature(SST)anomalies.The results show that the interannual variations of monthly precipitation in spring in SC have significant differences,and the correlations between each two months are very weak.All the interannual variations of precipitation in three months are related to a similar western North Pacific anomalous anticyclone(WNPAC),and the southwesterlies at the western flank of WNPAC bring abundant water vapor for the precipitation in SC.However,the WNPAC is influenced by tropical SST anomalies in different regions each month.The interannual variation of precipitation in March in SC is mainly influenced by the signal of El Nino-Southern Oscillation,and the associated SST anomalies in the equatorial central-eastern Pacific regulate the WNPAC through the Pacific-East Asia(PEA)teleconnection.In contrast,the WNPAC associated with the interannual variation of precipitation in April can be affected by the SST anomalies in the northwestern equatorial Pacific through a thermally induced Rossby wave response.The interannual variation of precipitation in May is regulated by the SST anomalies around the western Maritime Continent,which stimulates the development of low-level anomalous anticyclones over the South China Sea and east of the Philippine Sea by driving anomalous meridional vertical circulation. 展开更多
关键词 spring precipitation monthly diversity interannual variation southern China tropical sea surface temperature
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Progress on research and mitigation of wind-blown sand risk in Dunhuang Singing Sand Mountain and Crescent Spring Scenic area,China 被引量:1
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作者 BenLi Liu KeCun Zhang +6 位作者 JianJun Qu HaiJiang Li QingHe Niu ZhiShan An YingJun Pang LiHai Tan GenSheng Yang 《Research in Cold and Arid Regions》 CSCD 2023年第3期113-121,共9页
The Singing Sand Mountain and Crescent Spring Scenic Spot in Dunhuang,Northwest China is a world-renowned desert attraction that is also an integral component of the Dunhuang UNESCO Global Geopark.This scenic area und... The Singing Sand Mountain and Crescent Spring Scenic Spot in Dunhuang,Northwest China is a world-renowned desert attraction that is also an integral component of the Dunhuang UNESCO Global Geopark.This scenic area underwent a 30-year transformation,i.e.,from a severe sand risk with spring water threatened by sand burial due to dune deformation,to restoration of the original sand flow field and mitigation of the sand burial problem.The current paper summarizes the research on the intensive monitoring of the dynamic change of star dunes near the spring,observation of wind and sand flow movement,and then restoring the harmonic vibration of the sand particles(singing sand)that were previously silenced.The existing and prospective impacts of anthropogenic and natural forces on the deformation of the sand dunes are investigated by integrated methods,guiding the implementation of mitigating measures with significant ameliorative effects.Contrast to common sand control practices that aim to reduce wind speed and stop blown sands,our research highlights the importance of maintaining the natural wind flow field in stabilizing surrounding dunes.These mitigation measures consist of removing excessive vegetation and newly constructed buildings to recover the original wind flow field and sand transport activity.Such research and mitigation efforts ensure the scientific protection and restoration of the special desert landform,and contribute to the mutual enhancement of the conservation and exploitation of this desert scenic spot and similar sites. 展开更多
关键词 Singing Sand Mountain Crescent spring Wind-blown sand problem Wind flow field Star dune
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Tillage and straw mulching impacts on grain yield and water use efficiency of spring maize in Northern Huang–Huai–Hai Valley 被引量:28
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作者 Zhiqiang Tao Congfeng Li +5 位作者 Jingjing Li Zaisong Ding Jie Xu Xuefang Sun Peilu Zhou Ming Zhao 《The Crop Journal》 SCIE CAS CSCD 2015年第5期445-450,共6页
A two-year field experiment(2012–2013) was conducted to investigate the effects of two tillage methods and five maize straw mulching patterns on the yield, water consumption,and water use efficiency(WUE) of spring ma... A two-year field experiment(2012–2013) was conducted to investigate the effects of two tillage methods and five maize straw mulching patterns on the yield, water consumption,and water use efficiency(WUE) of spring maize(Zea mays L.) in the northern Huang–Huai–Hai valley of China. Compared to rotary tillage, subsoil tillage resulted in decreases in water consumption by 6.3–7.8% and increases in maize yield by 644.5–673.9 kg ha-1, soil water content by 2.9–3.0%, and WUE by 12.7–15.2%. Chopped straw mulching led to higher yield,soil water content, and WUE as well as lower water consumption than prostrate whole straw mulching. Mulching with 50% chopped straw had the largest positive effects on maize yield, soil water content, and WUE among the five mulching treatments. Tillage had greater influence on maize yield than straw mulching, whereas straw mulching had greater influence on soil water content, water consumption, and WUE than tillage. These results suggest that 50% chopped straw mulching with subsoil tillage is beneficial in spring maize production aiming at high yield and high WUE in the Huang–Huai–Hai valley. 展开更多
关键词 NORTHERN Huang–Huai–Hai VallEY spring maize croppi
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Subsoiling and Ridge Tillage Alleviate the High Temperature Stress in Spring Maize in the North China Plain 被引量:20
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作者 TAO Zhi-qiang SUI Peng +5 位作者 CHEN Yuan-quan LI Chao NIE Zi-jin YUAN Shu-fen SHI Jiang-tao GAO Wang-sheng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第12期2179-2188,共10页
High temperature stress(HTS) on spring maize(Zea mays L.) during the filling stage is the key factor that limits the yield increase in the North China Plain(NCP).Subsoiling(SS) and ridge tillage(R) were intr... High temperature stress(HTS) on spring maize(Zea mays L.) during the filling stage is the key factor that limits the yield increase in the North China Plain(NCP).Subsoiling(SS) and ridge tillage(R) were introduced to enhance the ability of spring maize to resist HTS during the filling stage.The field experiments were conducted during the 2011 and 2012 maize growing seasons at Wuqiao County,Hebei Province,China.Compared with rotary tillage(RT),the net photosynthetic rate,stomatal conductance,transpiration rate,and chlorophyll relative content(SPAD) of maize leaves was increased by 40.0,42.6,12.8,and 29.7% under SS,and increased by 20.4,20.0,5.4,and 14.2% under R,repectively.However,the treatments reduce the intercellular CO 2 concentration under HTS.The SS and R treatments increased the relative water content(RWC) by 11.9 and 6.2%,and the water use efficiency(WUE) by 24.3 and 14.3%,respectively,compared with RT.The SS treatment increased the root length density and soil moisture in the 0-80 cm soil profile,whereas the R treatment increased the root length density and soil moisture in the 0-40 cm soil profile compared with the RT treatment.Compared with 2011,the number of days with temperatures 33°C was more 2 d and the mean day temperature was higher 0.9°C than that in 2012,whereas the plant yield decreased by 2.5,8.5 and 10.9%,the net photosynthetic rate reduced by 7.5,10.5 and 18.0%,the RWC reduced by 3.9,5.6 and 6.2%,and the WUE at leaf level reduced by 1.8,5.2 and 13.1% in the SS,R and RT treatments,respectively.Both the root length density and the soil moisture also decreased at different levels.The yield,photosynthetic rate,plant water status,root length density,and soil moisture under the SS and R treatments declined less than that under the RT treatment.The results indicated that SS and R can enhance the HTS resistance of spring maize during the filling stage,and led to higher yield by directly improving soil moisture and root growth and indirectly improving plant water status,photosynthesis and grain filling.The study can provide a theoretical basis for improving yield of maize by adjusting soil tillage in the NCP. 展开更多
关键词 high temperature stress spring maize filling stage SUBSOILING ridge tillage
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On the Association between Spring Arctic Sea Ice Concentration and Chinese Summer Rainfall:A Further Study 被引量:41
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作者 武炳义 张人禾 Bin WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2009年第4期666-678,共13页
In our previous study, a statistical linkage between the spring Arctic sea ice concentration (SIC) and the succeeding Chinese summer rainfall during the period 1968-2005 was identified. This linkage is demonstrated ... In our previous study, a statistical linkage between the spring Arctic sea ice concentration (SIC) and the succeeding Chinese summer rainfall during the period 1968-2005 was identified. This linkage is demonstrated by the leading singular value decomposition (SVD) that accounts for 19% of the co-variance. Both spring SIC and Chinese summer rainfall exhibit a coherent interannual variability and two apparent interdecadal variations that occurred in the late 1970s and the early 1990s. The combined impacts of both spring Arctic SIC and Eurasian snow cover on the summer Eurasian wave train may explain their statistical linkage. In this study, we show that evolution of atmospheric circulation anomalies from spring to summer, to a great extent, may explain the spatial distribution of spring and summer Arctic SIC anomalies, and is dynamically consistent with Chinese summer rainfall anomalies in recent decades. The association between spring Arctic SIC and Chinese summer rainfall on interannual time scales is more important relative to interdecadal time scales. The summer Arctic dipole anomaly may serve as the bridge linking the spring Arctic SIC and Chinese summer rainfall, and their coherent interdecadal variations may reflect the feedback of spring SIC variability on the atmosphere. The summer Arctic dipole anomaly shows a closer relationship with the Chinese summer rainfall relative to the Arctic Oscillation. 展开更多
关键词 spring Arctic sea ice concentration summer rainfall Arctic dipole anomaly interannual and interdecadal variations
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基于Spring Cloud的分布式医疗数据平台建设
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作者 汪睿 胡珊珊 +1 位作者 陈敏莲 徐骁 《设备管理与维修》 2024年第4期16-19,共4页
为解决互联网时代医疗大数据的可靠存储问题,探索异构数据的有效处理方案,加强医疗数据检索能力。提出一种基于Spring Cloud的分布式医疗数据平台建设方案,该方案通过Spring Cloud技术构建分布式架构,选取MongoDB非关系型数据库作为分... 为解决互联网时代医疗大数据的可靠存储问题,探索异构数据的有效处理方案,加强医疗数据检索能力。提出一种基于Spring Cloud的分布式医疗数据平台建设方案,该方案通过Spring Cloud技术构建分布式架构,选取MongoDB非关系型数据库作为分布式存储,同时对数据进行标准化、分词等操作,从而实现一个异构数据可存储、系统高可用、规模易扩展、检索高效率的医疗数据平台。 展开更多
关键词 分布式 医疗数据 spring Cloud MONGODB
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Vertical seismic absorber utilizing inertance and negative stiffness implemented with gas springs
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作者 Kalogerakou M Paradeisiotis A Antoniadis I 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2023年第1期225-241,共17页
A novel implementation of negative stiffness elements(NSEs)is proposed,utilizing industrial grade nitrogen gas springs as pre-stressed stiffness elements in a configuration with lever arms.This NSE is combined with an... A novel implementation of negative stiffness elements(NSEs)is proposed,utilizing industrial grade nitrogen gas springs as pre-stressed stiffness elements in a configuration with lever arms.This NSE is combined with an inerter to form a stiff dynamic absorber(SDA)for vertical seismic protection of structures with base isolation.The SDA is optimized to minimize vertical accelerations while ensuring static structural integrity,excellent damping performance and containment of relative displacements.The introduction of gas springs in place of conventional linear springs addresses important practical limitations through features of non-linearity and industrial grade manufacturing.The proposed implementation is dimensioned for a 50-ton structure and evaluated numerically for 25 actual earthquake records,in comparison with a linear SDA model and an equivalent conventional damper(CD).Individual and averaged results of acceleration and displacement time histories demonstrate vastly superior response compared to CD regarding induced accelerations for similar displacements.Performance equivalency with the linear SDA model indicates the stability of the gas spring implementation while guaranteeing predictability,tested endurance,proper tolerances,and off-axis motion resistance without requiring additional guiding components,as opposed to conventional springs.These features render the proposed implementation a promising solution for the realization of NSEs in seismic protection. 展开更多
关键词 negative stiffness gas springs vertical seismic protection KDamper inerter
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