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北海钻井平台Winterization Basic符号的解读
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作者 张度镇 刘佳辉 +1 位作者 尹纪友 刘文 《船舶工程》 北大核心 2015年第S2期95-98,共4页
北海区域丰富的油气资源吸引了各种高精尖半潜钻井平台云集此地,各船厂、设计公司也争相研发适用于北海恶劣海况的半潜钻井平台。从长远的发展来看,Winterization Basic这一平台的入籍符号会逐渐成为适用于北海恶劣海况的半潜平台的最... 北海区域丰富的油气资源吸引了各种高精尖半潜钻井平台云集此地,各船厂、设计公司也争相研发适用于北海恶劣海况的半潜钻井平台。从长远的发展来看,Winterization Basic这一平台的入籍符号会逐渐成为适用于北海恶劣海况的半潜平台的最基本要求。目前烟台中集来福士海洋工程有限公司已经成功交付有3座半潜平台在北海区域服务,也即将交付第四座带有Winterization Basic这一入籍符号的半潜平台COSLProspector。本文以COSLProspector项目Winterization Basic设计为例,概述总结了整个基础、详细的施工设计过程的经验教训。 展开更多
关键词 北海钻井平台 winterization Basic
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Winter wheat yield improvement by genetic gain across different provinces in China 被引量:2
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作者 Wei Chen Jingjuan Zhang Xiping Deng 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第2期468-483,共16页
The replacement of winter wheat varieties has contributed significantly to yield improvement worldwide,with remarkable progress in China.Drawing on two sets of data,production yield from the National Bureau of Statist... The replacement of winter wheat varieties has contributed significantly to yield improvement worldwide,with remarkable progress in China.Drawing on two sets of data,production yield from the National Bureau of Statistics of China and experimental yield from literature,this study aims to(1)illustrate the increasing patterns of production yield among different provinces from 1978 to 2018 in China,(2)explore the genetic gain in yield and yield relevant traits through the variety replacement based on experimental yield from 1937 to 2016 in China,and(3)compare the yield gap between experimental yield and production yield.The results show that both the production and experimental yields significantly increased along with the variety replacement.The national annual yield increase ratio for the production yield was 1.67%from 1978 to 2018,varying from 0.96%in Sichuan Province to 2.78%in Hebei Province;such ratio for the experimental yield was 1.13%from 1937 to 2016.The yield gap between experimental and production yields decreased from the 1970s to the 2010s.This study reveals significant increases in some yield components consequent to variety replacement,including thousand-grain weight,kernel number per spike,and grain number per square meter;however,no change is shown in spike number per square meter.The biomass and harvest index consistently and significantly increased,whereas the plant height decreased significantly. 展开更多
关键词 genetic gain winter wheat YIELD yield components
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Will the Globe Encounter the Warmest Winter after the Hottest Summer in 2023? 被引量:2
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作者 Fei ZHENG Shuai HU +17 位作者 Jiehua MA Lin WANG Kexin LI Bo WU Qing BAO Jingbei PENG Chaofan LI Haifeng ZONG Yao YAO Baoqiang TIAN Hong CHEN Xianmei LANG Fangxing FAN Xiao DONG Yanling ZHAN Tao ZHU Tianjun ZHOU Jiang ZHU 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第4期581-586,共6页
In the boreal summer and autumn of 2023,the globe experienced an extremely hot period across both oceans and continents.The consecutive record-breaking mean surface temperature has caused many to speculate upon how th... In the boreal summer and autumn of 2023,the globe experienced an extremely hot period across both oceans and continents.The consecutive record-breaking mean surface temperature has caused many to speculate upon how the global temperature will evolve in the coming 2023/24 boreal winter.In this report,as shown in the multi-model ensemble mean(MME)prediction released by the Institute of Atmospheric Physics at the Chinese Academy of Sciences,a medium-to-strong eastern Pacific El Niño event will reach its mature phase in the following 2−3 months,which tends to excite an anomalous anticyclone over the western North Pacific and the Pacific-North American teleconnection,thus serving to modulate the winter climate in East Asia and North America.Despite some uncertainty due to unpredictable internal atmospheric variability,the global mean surface temperature(GMST)in the 2023/24 winter will likely be the warmest in recorded history as a consequence of both the El Niño event and the long-term global warming trend.Specifically,the middle and low latitudes of Eurasia are expected to experience an anomalously warm winter,and the surface air temperature anomaly in China will likely exceed 2.4 standard deviations above climatology and subsequently be recorded as the warmest winter since 1991.Moreover,the necessary early warnings are still reliable in the timely updated mediumterm numerical weather forecasts and sub-seasonal-to-seasonal prediction. 展开更多
关键词 winter climate El Niño seasonal forecast GMST
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The first factor affecting dryland winter wheat grain yield under various mulching measures: Spike number 被引量:1
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作者 Yingxia Dou Hubing Zhao +4 位作者 Huimin Yang Tao Wang Guanfei Liu Zhaohui Wang Sukhdev Malhi 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期836-848,共13页
Water is the key factor limiting dryland wheat grain yield.Mulching affects crop yield and yield components by affecting soil moisture.Further research is needed to determine the relationships between yield components... Water is the key factor limiting dryland wheat grain yield.Mulching affects crop yield and yield components by affecting soil moisture.Further research is needed to determine the relationships between yield components and soil moisture with yield,and to identify the most important factor affecting grain yield under various mulching measures.A long-term 9-yearifeld experiment in the Loess Plateau of Northwest China was carried out with three treatments:no mulch (CK),plastic mulch (M_(P)) and straw mulch (M_(S)).Yield factors and soil moisture were measured,and the relationships between them were explored by correlation analysis,structural equation modeling and significance analysis.The results showed that compared with CK,the average grain yields of M_(P) and M_(S) increased by 13.0and 10.6%,respectively.The average annual grain yield of the M_(P) treatment was 134 kg ha^(–1) higher than the M_(S) treatment.There were no significant differences in yield components among the three treatments (P<0.05).Soil water storage of the M_(S) treatment was greater than the M_(P) treatment,although the differences were not statistically signifiant.Soil water storage during the summer fallow period (SWSSF) and soil water storage before sowing (SWSS) of M_(S) were significantly higher than in CK,which increased by 38.5 and 13.6%,respectively.The relationship between M_(P) and CK was not statistically significant for SWSSF,but the SWSS in M_(P) was significantly higher than in CK.In terms of soil water storage after harvest (SWSH) and water consumption in the growth period(ET),there were no signi?cant differences among the three treatments.Based on the three analysis methods,we found that spike number and ET were positively correlated with grain yield.However,the relative importance of spike number to yield was the greatest in the M_(P )and M_(S) treatments,while that of ET was the greatest in CK.Suifcient SWSSF could indirectly increase spike number and ET in the three treatments.Based on these results,mulch can improve yield and soil water storage.The most important factor affecting the grain yield of dryland wheat was spike number under mulching,and ET with CK.These findings may help us to understand the main factors influencing dryland wheat grain yield under mulching conditions compared to CK. 展开更多
关键词 dryland winter wheat plastic mulch spike number straw mulch
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Spectral purification improves monitoring accuracy of the comprehensive growth evaluation index for film-mulched winter wheat 被引量:1
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作者 Zhikai Cheng Xiaobo Gu +5 位作者 Yadan Du Zhihui Zhou Wenlong Li Xiaobo Zheng Wenjing Cai Tian Chang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1523-1540,共18页
In order to further improve the utility of unmanned aerial vehicle(UAV)remote-sensing for quickly and accurately monitoring the growth of winter wheat under film mulching, this study examined the treatments of ridge m... In order to further improve the utility of unmanned aerial vehicle(UAV)remote-sensing for quickly and accurately monitoring the growth of winter wheat under film mulching, this study examined the treatments of ridge mulching,ridge–furrow full mulching, and flat cropping full mulching in winter wheat.Based on the fuzzy comprehensive evaluation (FCE) method, four agronomic parameters (leaf area index, above-ground biomass, plant height, and leaf chlorophyll content) were used to calculate the comprehensive growth evaluation index (CGEI) of the winter wheat, and 14 visible and near-infrared spectral indices were calculated using spectral purification technology to process the remote-sensing image data of winter wheat obtained by multispectral UAV.Four machine learning algorithms, partial least squares, support vector machines, random forests, and artificial neural network networks(ANN), were used to build the winter wheat growth monitoring model under film mulching, and accuracy evaluation and mapping of the spatial and temporal distribution of winter wheat growth status were carried out.The results showed that the CGEI of winter wheat under film mulching constructed using the FCE method could objectively and comprehensively evaluate the crop growth status.The accuracy of remote-sensing inversion of the CGEI based on the ANN model was higher than for the individual agronomic parameters, with a coefficient of determination of 0.75,a root mean square error of 8.40, and a mean absolute value error of 6.53.Spectral purification could eliminate the interference of background effects caused by mulching and soil, effectively improving the accuracy of the remotesensing inversion of winter wheat under film mulching, with the best inversion effect achieved on the ridge–furrow full mulching area after spectral purification.The results of this study provide a theoretical reference for the use of UAV remote-sensing to monitor the growth status of winter wheat with film mulching. 展开更多
关键词 mulched winter wheat machine learning fuzzy comprehensive evaluation comprehensive growth evaluation index unmanned aerial vehicle
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创伤性冠状动脉血肿致de Winter综合征心电图动态演变1例
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作者 王婷锭 俞海风 +1 位作者 刘洪庆 梁添蔚 《中国乡村医药》 2024年第7期46-48,共3页
创伤性冠状动脉(冠脉)血肿临床罕见,de Winter综合征是一种特殊类型的急性冠脉综合征。本文报道新昌县人民医院诊治的创伤性冠脉血肿致de Winter综合征,且心电图呈动态演变1例,其冠脉病变经冠脉造影及血管内超声(IVUS)证实。
关键词 创伤性冠状动脉血肿 de Winter综合征 心电图
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Different ENSO Impacts on Eastern China Precipitation Patterns in Early and Late Winter Associated with Seasonally-Varying Kuroshio Anticyclonic Anomalies
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作者 Jingrui YAN Wenjun ZHANG +1 位作者 Suqiong HU Feng JIANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第9期1691-1703,共13页
Winter precipitation over eastern China displays remarkable interannual variability,which has been suggested to be closely related to El Niño-Southern Oscillation(ENSO).This study finds that ENSO impacts on easte... Winter precipitation over eastern China displays remarkable interannual variability,which has been suggested to be closely related to El Niño-Southern Oscillation(ENSO).This study finds that ENSO impacts on eastern China precipitation patterns exhibit obvious differences in early(November-December)and late(January-February)winter.In early winter,precipitation anomalies associated with ENSO are characterized by a monopole spatial distribution over eastern China.In contrast,the precipitation anomaly pattern in late winter remarkably changes,manifesting as a dipole spatial distribution.The noteworthy change in precipitation responses from early to late winter can be largely attributed to the seasonally varying Kuroshio anticyclonic anomalies.During the early winter of El Niño years,anticyclonic circulation anomalies appear both over the Philippine Sea and Kuroshio region,enhancing water vapor transport to the entirety of eastern China,thus contributing to more precipitation there.During the late winter of El Niño years,the anticyclone over the Philippine Sea is further strengthened,while the one over the Kuroshio dissipates,which could result in differing water vapor transport between northern and southern parts of eastern China and thus a dipole precipitation distribution.Roughly the opposite anomalies of circulation and precipitation are displayed during La Niña winters.Further analysis suggests that the seasonally-varying Kuroshio anticyclonic anomalies are possibly related to the enhancement of ENSO-related tropical central-eastern Pacific convection from early to late winter.These results have important implications for the seasonal-tointerannual predictability of winter precipitation over eastern China. 展开更多
关键词 precipitation eastern China ENSO early winter late winter Kuroshio anticyclone
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Erratum to:Deriving Temporal and Vertical Distributions of Methane in Xianghe Using Ground-based Fourier Transform Infrared and Gas-analyzer
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作者 Denghui JI Minqiang ZHOU +6 位作者 Pucai WANG Yang YANG Ting WANG Xiaoyu SUN Christian HERMANS Bo YAO Gengchen WANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第2期377-377,共1页
“Diurnal variation of CH4 at the surface from spring to winter.The time units are in local time(+8 h UTC).The error bar is 1σfor all the observed hourly mean data within that season at that local time.”in the capti... “Diurnal variation of CH4 at the surface from spring to winter.The time units are in local time(+8 h UTC).The error bar is 1σfor all the observed hourly mean data within that season at that local time.”in the caption of Fig.8 on Page 604 should be“Diurnal variation of CH4 at the surface from spring to winter.The time units are in UTC.The error bar is 1σfor all the observed hourly mean data within that season at that local time.” 展开更多
关键词 WINTER SEASON INFRARED
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Geographical origin identification of winter jujube(Ziziphus jujuba Dongzao')by using multi-element fingerprinting with chemometrics
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作者 Xiabing Kong Qiusheng Chen +8 位作者 Min Xu Yihui Liu Xiaoming Li Lingxi Han Qiang Zhang Haoliang Wan Lu Liu Xubo Zhao Jiyun Nie 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第5期1749-1762,共14页
Winter jujube(Ziziphus jujuba'Dongzao')is greatly appreciated by consumers for its excellent quality,but brand infringement frequently occurs in the market.Here,we first determined a total of 38 elements in 16... Winter jujube(Ziziphus jujuba'Dongzao')is greatly appreciated by consumers for its excellent quality,but brand infringement frequently occurs in the market.Here,we first determined a total of 38 elements in 167 winter jujube samples from the main winter jujube producing areas of China by inductively coupled plasma mass spectrometer(ICP-MS).As a result,16 elements(Mg,K,Mn,Cu,Zn,Mo,Ba,Be,As,Se,Cd,Sb,Ce,Er,Tl,and Pb)exhibited significant differences in samples from different producing areas.Supervised linear discriminant analysis(LDA)and orthogonal projection to latent structures discriminant analysis(OPLS-DA)showed better performance in identifying the origin of samples than unsupervised principal component analysis(PCA).LDA and OPLS-DA had a mean identification accuracy of 87.84 and 94.64%in the testing set,respectively.By using the multilayer perceptron(MLP)and C5.0,the prediction accuracy of the models could reach 96.36 and 91.06%,respectively.Based on the above four chemometric methods,Cd,Tl,Mo and Se were selected as the main variables and principal markers for the origin identification of winter jujube.Overall,this study demonstrates that it is practical and precise to identify the origin of winter jujube through multi-element fingerprint analysis with chemometrics,and may also provide reference for establishing the origin traceability system of other fruits. 展开更多
关键词 winter jujube multi-element fingerprint analysis CHEMOMETRICS origin traceability
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Prediction of the potential distribution and analysis of the freezing injury risk of winter wheat on the Loess Plateau under climate change
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作者 Qing Liang Xujing Yang +9 位作者 Yuheng Huang Zhenwei Yang Meichen Feng Mingxing Qing Chao Wang Wude Yang Zhigang Wang Meijun Zhang Lujie Xiao Xiaoyan Song 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第9期2941-2954,共14页
Determining the suitable areas for winter wheat under climate change and assessing the risk of freezing injury are crucial for the cultivation of winter wheat.We used an optimized Maximum Entropy(MaxEnt)Model to predi... Determining the suitable areas for winter wheat under climate change and assessing the risk of freezing injury are crucial for the cultivation of winter wheat.We used an optimized Maximum Entropy(MaxEnt)Model to predict the potential distribution of winter wheat in the current period(1970-2020)and the future period(2021-2100)under four shared socioeconomic pathway scenarios(SSPs).We applied statistical downscaling methods to downscale future climate data,established a scientific and practical freezing injury index(FII)by considering the growth period of winter wheat,and analyzed the characteristics of abrupt changes in winter wheat freezing injury by using the Mann-Kendall(M-K)test.The results showed that the prediction accuracy AUC value of the MaxEnt Model reached 0.976.The minimum temperature in the coldest month,precipitation in the wettest season and annual precipitation were the main factors affecting the spatial distribution of winter wheat.The total suitable area of winter wheat was approximately 4.40×10^(7)ha in the current period.In the 2070s,the moderately suitable areas had the greatest increase by 9.02×10^(5)ha under SSP245 and the least increase by 6.53×10^(5)ha under SSP370.The centroid coordinates of the total suitable areas tended to move northward.The potential risks of freezing injury in the high-latitude and-altitude areas of the Loess Plateau,China increased significantly.The northern areas of Xinzhou in Shanxi Province,China suffered the most serious freezing injury,and the southern areas of the Loess Plateau suffered the least.Environmental factors such as temperature,precipitation and geographical location had important impacts on the suitable area distribution and freezing injury risk of winter wheat.In the future,greater attention should be paid to the northward boundaries of both the winter wheat planting areas and the areas of freezing injury risk to provide the early warning of freezing injury and implement corresponding management strategies. 展开更多
关键词 climate change scenarios winter wheat freezing injury risk DOWNSCALING MAXENT
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Avian responses to an extreme weather event:The case of the‘Filomena’snowstorm in Madrid(central Spain)
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作者 Carlos Lazaro Carlos Sanchez-García +1 位作者 Fabian Casas E.Jorge Tizado 《Avian Research》 SCIE CSCD 2024年第2期180-186,共7页
Cold spells and severe weather may have detrimental effects in wild birds,but owing to the stochastic nature of these events,it is not always possible to measure their impacts.In January 2021,a strong snowstorm known... Cold spells and severe weather may have detrimental effects in wild birds,but owing to the stochastic nature of these events,it is not always possible to measure their impacts.In January 2021,a strong snowstorm known as‘Filomena’affected Spain,mainly the region of Madrid(Central Spain),which was fully covered with snow and suffered freezing temperatures for a fortnight.Using bird surveys conducted in the winter-spring of 2020 and 2021(before and after Filomena)at same locations,we addressed the possible impact of the cold spell in three widespread gamebirds:Wood Pigeon(Columba palumbus),Eurasian Magpie(Pica pica)and Red-legged Partridge(Alectoris rufa).No significant abundance differences were found between years for none of the species and hunting pressure was only significantly reduced for Partridges,hence this species may have been negatively affected by Filomena.Results suggest that in response to Filomena,Pigeons conducted partial migration in search of better conditions,while Magpies aggregated in certain areas of Madrid and Partridges endured the harsh conditions within their home ranges.Our results highlight the importance to alleviate negative impacts of extreme weather events in wild birds through management actions,especially for sedentary species. 展开更多
关键词 Alectoris rufa Climate change Cold spell Columba palumbus Migration Pica pica WINTER
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Plastic mulch increases dryland wheat yield and water-use productivity,while straw mulch increases soil water storage
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作者 Hubing Zhao Guanfei Liu +5 位作者 Yingxia Dou Huimin Yang Tao Wang Zhaohui Wang Sukhdev Malhi Adnan Anwar Khan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第9期3174-3185,共12页
Amplifying drought stress and high precipitation variability impair dryland wheat production.These problems can potentially be minimized by using plastic mulch(PM)or straw mulch(SM).Therefore,wheat grain yield,soil wa... Amplifying drought stress and high precipitation variability impair dryland wheat production.These problems can potentially be minimized by using plastic mulch(PM)or straw mulch(SM).Therefore,wheat grain yield,soil water storage,soil temperature and water-use productivity of PM and SM treatments were compared with no mulch(CK)treatment on dryland wheat over a period of eight seasons.Compared to the CK treatment,PM and SM treatments on average significantly increased grain yield by 12.6 and 10.5%,respectively.Compared to the CK treatment,SM treatment significantly decreased soil daily temperature by 0.57,0.60 and 0.48℃ for the whole seasons,growing periods and summer fallow periods,respectively.In contrast,compared to the CK treatment,PM treatment increased soil daily temperature by 0.44,0.51 and 0.27℃ for the whole seasons,growing periods and summer fallow periods,respectively.Lower soil temperature under SM allowed greater soil water storage than under PM.Soil water storage pre-seeding was 17%greater under the SM than under the PM treatment.Soil water storage post-harvest was similar for the PM and SM treatments,but evapotranspiration was 4.5%higher in the SM than in the PM treatment.Consequently,water-use productivity was 6.6%greater under PM than under the SM treatment.Therefore,PM treatment increased dryland wheat yield and water-use productivity,while straw mulch increased soil water storage. 展开更多
关键词 plastic mulch soil water storage straw mulch water-use productivity winter wheat
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Shallow sub-lakes are essential for sustaining the successful wintering of waterbirds in Poyang Lake,China
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作者 Mengjie Lu Zhen Zhang +3 位作者 Peng Chen Changxin Xu Bin Gao Luzhang Ruan 《Avian Research》 SCIE CSCD 2024年第2期219-228,共10页
For migratory waterbirds,the quality of wintering habitat is related to spring migration and successful breeding in the next year.The availability of food resources in the habitat is critical and varies within water l... For migratory waterbirds,the quality of wintering habitat is related to spring migration and successful breeding in the next year.The availability of food resources in the habitat is critical and varies within water levels.Although the water-level fluctuations in Poyang Lake have been extremely variable interannually in recent years,the wintering waterbird populations have remained relatively stable.Hence,the mechanism of maintaining the stability is worth exploring.This study aimed to compare the distribution of vegetation and herbivorous wa-terbirds in 2015-2016 and 2016-2017,focusing on three shallow sub-lakes and one main lake are.The results showed that the emergence of tubers and the growth of Carex spp.provided a continuous food supply and habitat for wintering waterbirds with a gradual decline in the water level.Shallow sub-lakes supported almost all of the tuber-eating waterbirds(1.42-1.62×10^(5))and most geese(1.34-1.53×10^(6)).However,the main lake area,covered with Persicaria hydropiper,did not provide adequate and accessible food.This resulted in almost no distribution of tuber-eating waterbirds,with only a few geese congregating in early winter.Our results demonstrated that the shallow sub-lakes under human control provided a different environment from the main lake and are key to sustaining the successful wintering of hundreds of thousands of migratory waterbirds in Poyang Lake.Therefore,we recommend refining the anthropogenic management of the shallow sub-lakes to regulate the water level to ensure the carrying capacity of Poyang Lake. 展开更多
关键词 Anthropogenic management Carrying capacity Seasonal lake Water level Wintering habitat
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北京2022年冬奥会六足冰壶机器人机构设计与运动规划
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作者 Ke Yin Yue Gao +5 位作者 Feng Gao Xianbao Chen Yue Zhao Yuguang Xiao Qiao Sun Jing Sun 《Engineering》 SCIE EI CAS CSCD 2024年第4期15-31,共17页
When a curling rock slides on an ice sheet with an initial rotation,a lateral movement occurs,which is known as the curling phenomenon.The force of friction between the curling rock and the ice sheet changes continual... When a curling rock slides on an ice sheet with an initial rotation,a lateral movement occurs,which is known as the curling phenomenon.The force of friction between the curling rock and the ice sheet changes continually with changes in the environment;thus,the sport of curling requires great skill and experience.The throwing of the curling rock is a great challenge in robot design and control,and existing curling robots usually adopt a combination scheme of a wheel chassis and gripper that differs significantly from human throwing movements.A hexapod curling robot that imitates human kicking,sliding,pushing,and curling rock rotating was designed and manufactured by our group,and completed a perfect show during the Beijing 2022 Winter Olympics Games.Smooth switching between the walking and throwing tasks is realized by the robot’s morphology transformation based on leg configuration switching.The robot’s controlling parameters,which include the kicking velocity v_(k),pushing velocity v_(p),orientation angle θc,and rotation velocityω,are determined by aiming and sliding models according to the estimated equivalent friction coefficientμ_(equ)and ratio e of the front and back frictions.The stable errors between the target and actual stopping points converge to 0.2 and 1.105 m in the simulations and experiments,respectively,and the error shown in the experiments is close to that of a well-trained wheelchair curling athlete.This robot holds promise for helping ice-makers rectify ice sheet friction or assisting in athlete training. 展开更多
关键词 Legged robot Curling robot Winter Olympics Mechanism design Motion planning
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Changes in the adult sex ratio of six duck species breeding populations over two decades
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作者 Monika Homolkova Petr Musil +4 位作者 Diego Pavon-Jordan Dorota Gajdosova Zuzana Musilova Sarka Neuzilova Jan Zouhar 《Avian Research》 SCIE CSCD 2024年第2期202-210,共9页
Despite all efforts,long-term changes in the adult sex ratios of breeding duck populations are still unclear;this uncertainty is especially true for male-bias populations,which are often under the scrutiny of research... Despite all efforts,long-term changes in the adult sex ratios of breeding duck populations are still unclear;this uncertainty is especially true for male-bias populations,which are often under the scrutiny of researchers lacking convenient results for the active protection of endangered species.Species with male-bias populations are usually strongly affected by a decline in population size that leads to a higher extinction risk.In this study,we examined our long-term data of the abundance of breeding populations in six duck species(Mallard Anas platyrhynchos,Gadwall Mareca strepera,Red-crested Pochard Netta rufina,Common Pochard Aythya ferina,Tufted Duck Aythya fuligula,and Common Goldeneye Bucephala clangula)from fishponds in South Bohemia,Czechia,between 2004 and 2022.This evidence was used to assess long-term changes in the adult sex ratio in these breeding populations and investigate the possible effects of the NAO index(North Atlantic Oscillation index)on them,indicating climate conditions in winter.We determined a long-term decrease of the proportion of females in the breeding season in two of the six examined species:Common Pochard and Red-crested Pochard,which is driven by the long-term increase in the number of males in contrast to the decreasing or stable number of females likely caused by different migration behaviours between females and males.In the case of Common Pochard,in breeding populations,we estimated 60-65%of males in the early 2000s rising to 75-80%in the early 2020s.However,we establish no significant effects linked to climate conditions of the previous winter in these species as a crucial cause of the changes of the proportion of females in the breeding population. 展开更多
关键词 Adult sex ratio Breeding population Population dynamics Red-listed species WATERFOWL Winter weather conditions
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An integrated spatial planning of the mountainous landscapes for ski sports in a case area at the eastern Türkiye
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作者 SATIR Onur TOSUN Busra +2 位作者 COSKUN OZYOL Funda OZDEMIR Omer Faruk BERBEROGLU Suha 《Journal of Mountain Science》 SCIE CSCD 2024年第3期754-767,共14页
Mountainous regions have disadvantages in economic development because of harsh physical and climatic conditions.However,winter tourism activities are one of the key components for supporting economic development in t... Mountainous regions have disadvantages in economic development because of harsh physical and climatic conditions.However,winter tourism activities are one of the key components for supporting economic development in the highlands.Establishing a ski resort area supports direct and indirect employment in a region,and it stops immigration from mountainous regions to other places.This research aimed to assess the potential ski areas using a multi criteria evaluation technique in the Van region which is located in the eastern part of Türkiye.In this context,snow cover duration,sun effect,slope,slope length,elevation,population density,distance from main roads and lake visibility were used as input factors in the decision making process.Each factor was standardized using a fuzzy technique based on existing well-known ski centers in Türkiye.The weight of inputs was defined by applying a survey to the professional skiers.The most important factors were detected as transportation opportunities and snow covers whereas,the least important factors were elevation and population density.Additionally,lake visibility was very important to make a difference from other existing facilities in the region.Therefore,it was included as constraints and lake visible areas were extracted at the final stage of the research.Potential ski areas were mapped in three levels as professional,intermediate and beginner skiers.One of the suitable areas was selected as a sample projection and for the 3D simulation of the ski investment area.Potential costs and benefits were discussed.It was found that a ski tourism area investment can be amortized in 3 years in the region. 展开更多
关键词 Winter sports and tourism Decision making 3D simulation and modelling Landscape planning GIS
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Improved simulation of winter wheat yield in North China Plain by using PRYM-Wheat integrated dry matter distribution coefficient
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作者 Xuan Li Shaowen Wang +6 位作者 Yifan Chen Danwen Zhang Shanshan Yang Jingwen Wang Jiahua Zhang Yun Bai Sha Zhang 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第4期1381-1392,共12页
The accurate simulation of regional-scale winter wheat yield is important for national food security and the balance of grain supply and demand in China.Presently,most remote sensing process models use the“biomass... The accurate simulation of regional-scale winter wheat yield is important for national food security and the balance of grain supply and demand in China.Presently,most remote sensing process models use the“biomass×harvest index(HI)”method to simulate regional-scale winter wheat yield.However,spatiotemporal differences in HI contribute to inaccuracies in yield simulation at the regional scale.Time-series dry matter partition coefficients(Fr)can dynamically reflect the dry matter partition of winter wheat.In this study,Fr equations were fitted for each organ of winter wheat using site-scale data.These equations were then coupled into a process-based and remote sensingdriven crop yield model for wheat(PRYM-Wheat)to improve the regional simulation of winter wheat yield over the North China Plain(NCP).The improved PRYM-Wheat model integrated with the fitted Fr equations(PRYM-Wheat-Fr)was validated using data obtained from provincial yearbooks.A 3-year(2000-2002)averaged validation showed that PRYM-Wheat-Fr had a higher coefficient of determination(R^(2)=0.55)and lower root mean square error(RMSE=0.94 t ha^(-1))than PRYM-Wheat with a stable HI(abbreviated as PRYM-Wheat-HI),which had R^(2) and RMSE values of 0.30 and 1.62 t ha^(-1),respectively.The PRYM-Wheat-Fr model also performed better than PRYM-Wheat-HI for simulating yield in verification years(2013-2015).In conclusion,the PRYM-Wheat-Fr model exhibited a better accuracy than the original PRYM-Wheat model,making it a useful tool for the simulation of regional winter wheat yield. 展开更多
关键词 dry matter partition remote sensing model winter wheat yield North China Plain
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Pacific oyster(Crassostrea gigas)shell growth duration in a year in Bohai Bay and implication for its carbon sink potential
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作者 Wen-yu Wang Chang-fu Fan +2 位作者 Zhao-jun Song Hong Wang Fu Wang 《China Geology》 CAS CSCD 2024年第4期653-660,共8页
Oyster is a bivalve mollusk widely distributed in estuarine and shallow sea environments.Its growth and burial process is a carbon sequestration and storage process.Oyster shell may stop growing due to suffer from fre... Oyster is a bivalve mollusk widely distributed in estuarine and shallow sea environments.Its growth and burial process is a carbon sequestration and storage process.Oyster shell may stop growing due to suffer from freeze shock during the winter season within a temperate climate,therefore,in order to study the carbon sequestration capacity of oysters we need to know the water temperature at which the shell suffer from winter freeze shock.This study examinesδ^(18)O profiles across consecutive micro-growth layers found in three modern Pacific oyster shells from the northwest coast of Bohai Bay.A total of 165 oxygen isotope values from sequential samples of their left shells showed periodically varying values,and the variation fluctuation of oxygen isotope values was 4.97‰on average.According to the variation range of the oxygen isotope value of the shell,combined with the sea surface temperature and the sea surface salinity data of the water in which the oysters grew,the water temperature that suffer from winter freeze shock and stops or retards the growth of Pacific oysters in Bohai Bay is about 8.3℃,and the corresponding period is from December to March of the following year.The calcification time of oysters within one year is nearly a month longer than previously thought,therefore,its carbon sink potential is also improved. 展开更多
关键词 Crassostrea gigas Winter freeze shock Oxygen isotope Bohai Bay Carbon sequestration and storage Environmental geological survey
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Scientific Advances and Weather Services of the China Meteorological Administration’s National Forecasting Systems during the Beijing 2022 Winter Olympics
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作者 Guo DENG Xueshun SHEN +23 位作者 Jun DU Jiandong GONG Hua TONG Liantang DENG Zhifang XU Jing CHEN Jian SUN Yong WANG Jiangkai HU Jianjie WANG Mingxuan CHEN Huiling YUAN Yutao ZHANG Hongqi LI Yuanzhe WANG Li GAO Li SHENG Da LI Li LI Hao WANG Ying ZHAO Yinglin LI Zhili LIU Wenhua GUO 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期767-776,共10页
Since the Beijing 2022 Winter Olympics was the first Winter Olympics in history held in continental winter monsoon climate conditions across complex terrain areas,there is a deficiency of relevant research,operational... Since the Beijing 2022 Winter Olympics was the first Winter Olympics in history held in continental winter monsoon climate conditions across complex terrain areas,there is a deficiency of relevant research,operational techniques,and experience.This made providing meteorological services for this event particularly challenging.The China Meteorological Administration(CMA)Earth System Modeling and Prediction Centre,achieved breakthroughs in research on short-and medium-term deterministic and ensemble numerical predictions.Several key technologies crucial for precise winter weather services during the Winter Olympics were developed.A comprehensive framework,known as the Operational System for High-Precision Weather Forecasting for the Winter Olympics,was established.Some of these advancements represent the highest level of capabilities currently available in China.The meteorological service provided to the Beijing 2022 Games also exceeded previous Winter Olympic Games in both variety and quality.This included achievements such as the“100-meter level,minute level”downscaled spatiotemporal resolution and forecasts spanning 1 to 15 days.Around 30 new technologies and over 60 kinds of products that align with the requirements of the Winter Olympics Organizing Committee were developed,and many of these techniques have since been integrated into the CMA’s operational national forecasting systems.These accomplishments were facilitated by a dedicated weather forecasting and research initiative,in conjunction with the preexisting real-time operational forecasting systems of the CMA.This program represents one of the five subprograms of the WMO’s high-impact weather forecasting demonstration project(SMART2022),and continues to play an important role in their Regional Association(RA)II Research Development Project(Hangzhou RDP).Therefore,the research accomplishments and meteorological service experiences from this program will be carried forward into forthcoming highimpact weather forecasting activities.This article provides an overview and assessment of this program and the operational national forecasting systems. 展开更多
关键词 Beijing Winter Olympic Games CMA national forecasting system data assimilation ensemble forecast bias correction and downscaling machine learning-based fusion methods
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River width and depth as key factors of diurnal activity energy expenditure allocation for wintering Spot-billed Ducks in the Xin'an River Basin
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作者 Chao Yu Xuying Lu +3 位作者 Deli Sun Mengnan Chu Xueyun Li Qun Li 《Avian Research》 SCIE CSCD 2024年第1期116-122,共7页
Rivers are important habitats for wintering waterbirds.However,they are easily influenced by natural and human activities.An important approach for waterbirds to adapt to habitats is adjusting the activity time and en... Rivers are important habitats for wintering waterbirds.However,they are easily influenced by natural and human activities.An important approach for waterbirds to adapt to habitats is adjusting the activity time and energy expenditure allocation of diurnal behavior.The compensatory foraging hypothesis predicts that increased energy expenditure leads to longer foraging time,which in turn increases food intake and helps maintain a constant energy balance.However,it is unclear whether human-disturbed habitats result in increased energy expenditure related to safety or foraging.In this study,the scan sample method was used to observe the diurnal behavior of the wintering Spot-billed Duck(Anas poecilorhyncha) in two rivers in the Xin’an River Basin from October 2021 to March 2022.The allocation of time and energy expenditure for activity in both normal and disturbed environments was calculated.The results showed that foraging accounted for the highest percentage of time and energy expenditure.Additionally,foraging decreased in the disturbed environment than that in the normal environment.Resting behavior showed the opposite trend,while other behaviors were similar in both environments.The total diurnal energy expenditure of ducks in the disturbed environment was greater than that in the normal environment,with decreased foraging and resting time percentage and increased behaviors related to immediate safety(swimming and alert) and comfort.These results oppose the compensatory foraging hypothesis in favor of increased security.The optimal diurnal energy expenditure model included river width and water depth,which had a positive relationship;an increase in either of these two factors resulted in an increase in energy expenditure.This study provides a better understanding of energy allocation strategies underlying the superficial time allocation of wintering waterbirds according to environmental conditions.Exploring these changes can help understand the maximum fitness of wintering waterbirds in response to nature and human influences. 展开更多
关键词 Diurnal behavior activities River factors Time and energy expenditure allocation Wintering Spot-billed Duck Xin’an River Basin
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