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Effect of Temperature on Frost-Free Days and Length of Crop Growing Season across Southern Ontario
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作者 Ramesh Pall Rudra Rituraj Shukla +2 位作者 Trevor Dickinson Pradeep Kumar Goel Jaskaran Dhiman 《American Journal of Climate Change》 2023年第4期700-718,共19页
Climate change has an impact on various climatic variables. In this study our focus is mainly on temperature characteristics of climate parameter. In temperate and humid regions like southern Ontario, the effect of cl... Climate change has an impact on various climatic variables. In this study our focus is mainly on temperature characteristics of climate parameter. In temperate and humid regions like southern Ontario, the effect of climate change on Frost-free days in winter is distinctive. The average annual temperature is going upward but the extreme increase is in the winter temperature. Winter average temperature is going up by about 2˚C. However, extreme daily minimum temperature is going up by more than 3˚C. This climate effect has a great impact on the nature of precipitation and length of frost-free days. The snowfall over winter months is decreasing and the rainfall is increasing. However, the number of frost-free days during late fall months, early winter months, late winter months and early spring months are increasing. This result reveals an increase in length of the growing season. This research focuses on the effect of change in climatic variables on Frost-free days in Southern Ontario. Therefore, special attention should be given to the effect of change in climate Frost-free conditions on length of crop growing in winter season for potential investigation. 展开更多
关键词 Climate Change Minimum Temperature frost-free days SNOWFALL Crop Growing Season Southern Ontario
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Determining the differences in O_(3)-NO_(x)-VOCs sensitivity between sauna and roast days
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作者 Yuting Liu Yinghong Wang +9 位作者 Yusi Liu Mengtian Cheng Baoxian Liu Tao Song Bo Hu Dan Yao Miao Yu Yu Shi Guiqian Tang Yuesi Wang 《Journal of Environmental Sciences》 2025年第11期605-614,共10页
Temperature is a key meteorological factor that affects tropospheric ozone(O_(3)),with both humid-heat(sauna days)and dry-heat(roast days)conditions leading to O_(3) exceedances.However,the mechanisms influencing O_(3... Temperature is a key meteorological factor that affects tropospheric ozone(O_(3)),with both humid-heat(sauna days)and dry-heat(roast days)conditions leading to O_(3) exceedances.However,the mechanisms influencing O_(3) formation and degradation under these two weather conditions remain unclear.Therefore,experiments were conducted in Beijing from 2019 to 2021 to observe O_(3),its precursors,and related meteorological elements.A total of 18 days with O_(3) exceedances were selected,including 10 sauna days and 8 roast days.The results of this study revealed that on roast days,the sensible heat flux was 143.5 W/m^(2) greater and the wind speed gradient was 0.018 s^(-1) greater than those on sauna days,indicating more intense thermal and dynamic turbulence.The strong turbulence enhanced the vertical cycle of nitrogen dioxide(NO_(2))and O_(3),resulting in a 58.2μg/(m^(2)·h)increase in NO_(2) upward transport rate and a 1034.4μg/(m^(2)·h)increase in O_(3) downward transport rate on roast days than sauna days.Subsequently,a box model analysis was used to examine O_(3) formation under the two types of weather conditions,revealing that the NO_(2)-O_(3) vertical cycling speed dominated the O_(3) sensitivity.The O_(3) sensitivity was synergistically controlled by nitrogen oxides(NO_(x))and volatile organic compounds on sauna days,while it tended to be NO_(x)-limited on roast days.The aim of this study was to provide a scientific theoretical basis for the control of O_(3) under different types of high temperature weather conditions. 展开更多
关键词 Ozone sensitivity Sauna days Roast days Thermal turbulence Dynamic turbulence
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Amplifying Marginalized Voices in Media Coverage of Gender-Based Violence During the 16 Days of Activism in Tanzania
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作者 Khamis Juma Abdalla 《Journalism and Mass Communication》 2025年第3期170-179,共10页
This paper presents the findings of a two-week monitoring project on Gender Based Violence(GBV)in Tanzanian and explores how the media outlets frame the marginalized voices,institutional narratives,and intersectional ... This paper presents the findings of a two-week monitoring project on Gender Based Violence(GBV)in Tanzanian and explores how the media outlets frame the marginalized voices,institutional narratives,and intersectional inclusivity.Drawing qualitative approach and analysis of media coverage of GBV during the 202416 Days of Activism campaign remarkably November 25 to December 10,2024,it reveals the extent that media platforms amplify or marginalize survivor voices.Through two weeks of media monitoring across print,broadcast,and social media including sources notably Mwananchi,TBC1,Cloud FM,and advocacy-driven digital platforms and campaigns through#EndGBVNow and#16DaysOfActivism the study explores recurring themes,language use,tone,and inclusivity.Guided by critical gender theories including Judith Butler’s gender performativity and Gave Tuchman’s symbolic annihilation,the analysis reveals media’s dual role in either perpetuating or challenging patriarchal narratives.Findings indicate that traditional media often foreground prevailing institutional voices while underrepresenting marginalized groups,especially rural women and women with disabilities,portraying harmful cultural practices like FGM and child marriage as community challenges rather than universal human rights violation.Conversely,social media emerged as a transformative space for survivor-led advocacy.Hence the study calls for inclusive,ethical,and survivor-centered media reporting as well as strategic integration of digital and mainstream media to promote justice and policy reform in GBV reporting. 展开更多
关键词 16 days of Activism in Tanzania feminist media studies gender-based violence gender performativity media monitoring media and social justice symbolic annihilation
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Variations of Frost-free Period and Its Impact on Grain Yields in Henan Province during 1961-2013 被引量:4
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作者 闫军辉 傅辉 +1 位作者 周红升 徐新创 《Agricultural Science & Technology》 CAS 2015年第8期1588-1591,1692,共5页
The aim of this study was to investigate the responses of frost dates to global warming and its influences on grain yields. In this study, based on the frost date series defined by daily minimum ground temperature, th... The aim of this study was to investigate the responses of frost dates to global warming and its influences on grain yields. In this study, based on the frost date series defined by daily minimum ground temperature, the spatial and temporal characteristics of first frost date (FFD), last frost date (LFD) and frost-free period (FFP) were analyzed. The impact of extending FFP on major crop yields was also studied. The results were as follows: FFD showed a significantly delaying trend of 2.2 d/10 y, and LFD presented an advancing trend of 2.4 d/10 y. FFP extended at a rate of 4.5 d/10 y due to the later FFD and earlier LFD. The most obvious trend of FFD was in westem Henan, while the most significant trend of LFD and FFP oc- curred in south central parts of the study area. However, in eestem region, the trends of FFD, LFD and FFP were not so obvious. Major crop yield showed a sig- nificant correlation with frost-free period for Henan during 1961-2013. The yields of grain, rice, wheat, and maize increased by 79.5, 90.0, 79.5 and 70.5 kg/hm2 with FFP extending by one day. 展开更多
关键词 Daily minimum ground temperature frost-free period Grain yield Henan province 1961-2013
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Fourteen cases of chronic gastritis with stomach cold treated by long snake moxibustion on dog days 被引量:4
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作者 赵中亭 李瑛 张晓凌 《World Journal of Acupuncture-Moxibustion》 2014年第3期57-60,68,共5页
Objective To observe the clinical efficacy of long snake moxibustion in treating chronic gastritis with stomach cold on dog days. Methods Fourteen cases of chronic gastritis with stomach cold were treated by long snak... Objective To observe the clinical efficacy of long snake moxibustion in treating chronic gastritis with stomach cold on dog days. Methods Fourteen cases of chronic gastritis with stomach cold were treated by long snake moxibustion on the first day of the first, second and the last of dog days respectively in 2012 and 2013. The acupoint area was covered by the ginger cake, and a bar of triangle-shaped moxa cone was laid on the ginger cake, and moxibustion began by igniting the upper angle of the moxa cone. Long snake moxibustion with two moxa cones burned up in sequence was conducted around the area of Zhongwan (中脘 CV 12) of upper abdomen (covering Shangwan (上脘 CV 13), CV 12, Jianli (建里 CV 114 Xiawan (下脘 CV 10) and Shuifen (水分 cv 9), as well as Futonggu (腹通谷 KI 20), Yindu (阴都 KI 19), Shiguan (石关 KI 18) and Shangqu (商曲 KI 27) along the kidney meridian of foot-shaoyin), and then the moxibustion with two moxa cones burned up in sequence was conducted around the lower thoracic spine at the back (covering Jinsuo (筋缩 GV 8), Zhongshu (中枢 GV 7), Jizhong (脊中 GV 6) and Xuanshu (悬枢 GV 5) as well as Jiaji (夹脊 EX-B 2) extending from T 9 to T 12 and L i with the governor vessel as the centerline at the back), and the treatment lasted for about 40 min. The treatment was made three times a year, and with a total of six times in two years. The efficacy was statistically evaluated after the course of the treatment. Results Among the 14 patients, recently clinically cured for 2 cases, markedly effective for 7 cases, effective for 4 cases and ineffective for i case, with the total effective rate of 92.9%. Conclusion Efficacy of long snake moxibustion in treating chronic gastritis with stomach cold on dog days is effective and clinical symptoms are significantly improved. 展开更多
关键词 chronic gastritis stomach cold dog days long snake moxibustion
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Days Matter软件预警功能在口腔专科医院物品效期管理的应用 被引量:5
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作者 杨冬叶 侯明娇 +1 位作者 刘晓刚 林丽婷 《护理学杂志》 CSCD 北大核心 2019年第23期62-64,共3页
目的探讨Days Matter软件预警功能对口腔专科医院物品效期自动化管理的效果。方法将科室物品分成仪器设备、耗材(常用和不常用类)两大类物品,运用Days Matter软件导入仪器设备及不常用耗材物品有效期并设置提醒功能。比较使用前后3个月... 目的探讨Days Matter软件预警功能对口腔专科医院物品效期自动化管理的效果。方法将科室物品分成仪器设备、耗材(常用和不常用类)两大类物品,运用Days Matter软件导入仪器设备及不常用耗材物品有效期并设置提醒功能。比较使用前后3个月每月护士检查该类物品效期所需平均时间。结果使用前,护士每月检查物品效期所需时间为(97.03±3.63)min,使用后为(26.73±1.19)min,使用前后比较,差异有统计学意义(P<0.01)。结论Days Matter软件操作简单,能精准监控物品效期,实现数据共享,节省检查时间。 展开更多
关键词 days Matter软件 医疗物品 仪器设备 医疗耗材 有效期 自动化管理
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Analysis of Causes for An Unusual Cloudy-rainy Weather for Several Days in Autumn 被引量:1
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作者 张景珍 张莉 +1 位作者 李建明 李静 《Meteorological and Environmental Research》 CAS 2010年第10期20-24,共5页
Cloudy-rainy weather for several days in 2007 was featured with the longest duration and the most serious extent of injury since the time from which there was meteorology observation record in Shandong.The causes of t... Cloudy-rainy weather for several days in 2007 was featured with the longest duration and the most serious extent of injury since the time from which there was meteorology observation record in Shandong.The causes of this process were analyzed in this article in terms of general circulation,character of physical quantity and tropical cyclone.The result showed that the precipitation process was a long wave adjustment process and it took place during the transformation process of general circulation turning from the zonal to the radial.During the cloudy-rainy weather process,the Ural mountain ridge and the Western Pacific subtropical high were more abnormally strong and in the further north than that in any other years.The tropical cyclone in the south of the subtropical cyclone activity was more frequent.There was more shortwave in middle latitudes of Asian.The cold air masses Siberia went down south.The cold air masses joined with the current of air in the Lower Yellow River.This led to the lasting cloudy-rainy weather for several days in Shandong. 展开更多
关键词 Cloudy-rainy weather for several days General circulation Physics characteristics Analysis of the causes China
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混合方法:教育游戏评价研究的理想范式——以80Days教育游戏项目为例 被引量:1
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作者 庄科君 贺宝勋 《软件导刊》 2013年第3期189-191,共3页
教育游戏评价是教育游戏设计开发过程中的核心环节之一,是一项综合的、多准则、多因素的复杂工程。评价过程应该采用科学的评价研究范式,以避免信度与效度的缺失。在目前国内教育游戏评价研究几乎空白的境遇下,以欧盟委员会FP7框架计划... 教育游戏评价是教育游戏设计开发过程中的核心环节之一,是一项综合的、多准则、多因素的复杂工程。评价过程应该采用科学的评价研究范式,以避免信度与效度的缺失。在目前国内教育游戏评价研究几乎空白的境遇下,以欧盟委员会FP7框架计划下的科研项目———80Days教育游戏项目为例,介绍了混合方法下的教育游戏评价研究范式,以期对我国教育游戏评价研究与实践有所帮助。 展开更多
关键词 教育游戏 混合方法 研究范式 80days
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The Absurdity of Happy Days
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作者 杨樱 《英语广场(学术研究)》 2012年第8期36-38,共3页
Happy Days,one of Samuel Beckett's renowned works,is remarkable for its absurdity.The paper approaches the predominant feature from such aspects as fragmented characters,disconnected language,peculiar structure an... Happy Days,one of Samuel Beckett's renowned works,is remarkable for its absurdity.The paper approaches the predominant feature from such aspects as fragmented characters,disconnected language,peculiar structure and grotesque stagecraft. 展开更多
关键词 Happy days ABSURDITY fragmented characters disconnected language peculiar structure grotesque stagecraft
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On Aesthetic Representation at Phonological Level in English Versions of Zhu Ziqing's Lyric Prose Transient Days
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作者 孔令会 《海外英语》 2012年第13期176-177,共2页
The paper analyses aesthetic message at phonological level of Zhu Ziqing's lyric prose Transient Days and explores how such message is represented in English versions respectively translated by Zhang Peiji and Zhu... The paper analyses aesthetic message at phonological level of Zhu Ziqing's lyric prose Transient Days and explores how such message is represented in English versions respectively translated by Zhang Peiji and Zhu Chunshen. 展开更多
关键词 ZHU Ziqing TRANSIENT days PHONOLOGICAL LEVEL aesth
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On the Main Characters in“Days of the Butterfly”
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作者 李伟娟 《海外英语》 2016年第24期169-170,共2页
"Days of the Butterfly"was one of Alice Munro's short stories written in 1950 s, when she was still a new hand. This paper will mainly focus on the development of the main characters in the story, includ... "Days of the Butterfly"was one of Alice Munro's short stories written in 1950 s, when she was still a new hand. This paper will mainly focus on the development of the main characters in the story, including Myra, the black girl who was the heroine, the teacher Miss Darling, and the Narrator"I". In portraying these characters, Munro adopted several writing techniques including conversation, detailed description, psychological description and so on. She vividly transferred those characters into paper. 展开更多
关键词 Munro "days of the Butterfly" main characters Myra Miss Darling
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水仙花日(Daffodil Days)简介
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作者 窦剑 《花卉》 2019年第9期47-48,共2页
Daffodil为石蒜科水仙属(Narcissus)植物的统称,它们是一类具膜质有皮鳞茎的多年生草本,通常于春季开花。万物萧飒的冬季,水仙的叶片破土而出(图1)。待到早春时节,水仙花儿迸放(图2),拉开春色满园的序幕。而当春夏交替之季,地上的绿叶... Daffodil为石蒜科水仙属(Narcissus)植物的统称,它们是一类具膜质有皮鳞茎的多年生草本,通常于春季开花。万物萧飒的冬季,水仙的叶片破土而出(图1)。待到早春时节,水仙花儿迸放(图2),拉开春色满园的序幕。而当春夏交替之季,地上的绿叶逐渐枯黄倒伏(图3),地下鳞茎进入休眠。水仙如此般,一岁一枯荣、周而复始。 展开更多
关键词 水仙花 days 多年生草本 石蒜科 鳞茎 早春 倒伏 枯黄
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An Abrupt Increase in the Summer High Temperature Extreme Days across China in the mid-1990s 被引量:24
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作者 魏科 陈文 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2011年第5期1023-1029,共7页
Based on the daily maximum surface air temperature records from an updated homogenized temperature dataset for 549 Chinese stations during 1960-2008,we reveal that there is an abrupt increase in the number of days wit... Based on the daily maximum surface air temperature records from an updated homogenized temperature dataset for 549 Chinese stations during 1960-2008,we reveal that there is an abrupt increase in the number of days with high temperature extremes (HTEs,an HTE day is defined when the maximum temperature exceeds the 95th percentile of the daily maximum temperature distributions) across China in the mid-1990s.Before this regime shift,the average number of HTE days is about 2.9 d yr 1 during the period from the 1970s to the early 1990s,while it rocketed to about 7.2 d yr 1 after the mid-1990s.We show that the significant HTE day increase occurs uniformly across the whole of China after the regime shift.The observational evidence raises the possibility that this change in HTE days is associated with global-scale warming as well as circulation adjustment.Possible causes for the abrupt change in the HTE days are discussed,and the circulation adjustment is suggested to play a crucial role in the increase in HTE days in this region. 展开更多
关键词 high temperature extremes hot days long-term trend regime shift
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Changes of heating and cooling degree days over China in response toglobal warming of 1.5℃, 2℃, 3℃ and 4℃ 被引量:9
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作者 SHI Ying ZHANG Dong-Feng +1 位作者 XU Ying ZHOU Bo-Tao 《Advances in Climate Change Research》 SCIE CSCD 2018年第3期192-200,共9页
Future changes of heating degree days (HDD) and cooling degree days (CDD) in the 21st century with and without considering populationfactor are investigated based on four sets of climate change simulations over Ea... Future changes of heating degree days (HDD) and cooling degree days (CDD) in the 21st century with and without considering populationfactor are investigated based on four sets of climate change simulations over East Asia using the regional climate model version 4.4 (RegCM4.4)driven by the global models of CSIRO-Mk3-6-0, EC-EARTH, HadGEM2-ES, and MPI-ESM-MR. Under global warming of 1.5℃, 2℃, 3℃,and 4℃, significant decrease of HDD can be found over China without considering population factor, with greater decrease over high elevationand high latitude regions, including the Tibetan Plateau, the northern part of Northeast China, and Northwest China; while population-weightedHDD increased in areas where population will increase in the future, such as Beijing, Tianjin, parts of southern Hebei, northern Shandong andHenan provinces. Similarly, the CDD projections with and without considering population factor are largely different. Specifically, withoutconsidering population, increase of CDD were observed over most parts of China except the Tibetan Plateau where the CDD remained zerobecause of the cold climate even under global warming; while considering population factor, the future CDD decreases in South China andincreases in North China, the Sichuan Basin, and the southeastern coastal areas, which is directly related to the population changes. The differentfuture changes of HDD and CDD when considering and disregarding the effects of population show that population distribution plays animportant role in energy consumption, which should be considered in future research. 展开更多
关键词 REGIONAL CLIMATE model Global WARMING of 1.5 2℃ 3℃ and 4℃ Heating DEGREE days Cooling DEGREE days China
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Analysis of China's Haze Days in the Winter Half-Year and the Climatic Background during 1961–2012 被引量:6
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作者 SONG Lian-Chun GAO Rong +1 位作者 LI Ying WANG Guo-Fu 《Advances in Climate Change Research》 SCIE 2014年第1期1-6,共6页
The characteristics of haze days and the climatic background are analyzed by using daily observations of haze,precipitation,mean and maximum wind speed of 664 meteorological stations for the period of 1961–2012.The r... The characteristics of haze days and the climatic background are analyzed by using daily observations of haze,precipitation,mean and maximum wind speed of 664 meteorological stations for the period of 1961–2012.The results show that haze days occur significantly more often in eastern China than in western China.The annual number of haze days is 5–30 d in most parts of central-eastern China,with some areas experiencing more than 30 d,while less than 5 d are averagely occurring in western China.Haze days are mainly concentrated in the winter half-year,with most in winter,followed by autumn,spring,and then summer.Nearly 20%of annual haze days are experienced in December.The haze days in central-eastern China in the winter half-year have a significant increasing trend of 1.7 d per decade during 1961–2012.There were great increases in haze days in the 1960s,1970s and the beginning of the 21st century.There was also significant abrupt changes of haze days in the early 1970s and 2000s.From 1961 to 2012,haze days in the winter half-year increased in South China,the middle-lower reaches of the Yangtze River,and North China,but decreased in Northeast China,eastern Northwest China and eastern Southwest China.The number of persistent haze is rising.The Longer the haze,the greater the proportion to the number persistent haze.Certain climatic conditions exacerbated the occurrence of haze.The correlation coefficient between haze days and precipitation days in the winter half-year is mainly negative in central-eastern China.The precipitation days show a decreasing trend in most parts of China,with a rate of around–4.0 d per decade in central-eastern China,which reduces the sedimentation capacity of atmospheric pollutants.During the period of 1961–2012,the correlation coefficients between haze days and mean wind speed and strong wind days are mainly negative in central-eastern China,while there exists positive correlation between haze days and breeze days in the winter half-year.The mean wind speed and strong wind days are decreasing,while breeze days are increasing in most parts of China,which is benefitial to the reduction of the pollutants diffusion capacity.As a result,haze occurs more easily. 展开更多
关键词 HAZE winter half-year precipitation days wind speed
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Distribution and trend on consecutive days of severe weathers in China during 1959–2014 被引量:3
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作者 史军 温康民 崔林丽 《Journal of Geographical Sciences》 SCIE CSCD 2016年第6期658-672,共15页
Based on daily surface climate data and weather phenomenon data, the spatial and temporal distribution and trend on the number of consecutive days of severe weathers were analyzed in China during 1959-2014. The result... Based on daily surface climate data and weather phenomenon data, the spatial and temporal distribution and trend on the number of consecutive days of severe weathers were analyzed in China during 1959-2014. The results indicate that the number of consecutive days for hot weathers increased at a rate of 0.1 day per decade in China as a whole, while that for cold weathers, snowfall weathers, thunderstorm weathers and foggy weathers showed significant decreasing trends at rates of 1.4, 0.3, 0.4 and 0.4 day per decade, re- spectively. Spatially, there were more consecutive hot days and rainstorm days in southeast- ern China, and more consecutive cold days and snowfall days in northeastern China and western China. Consecutive thunderstorm days were more in southern China and south- western China, and consecutive foggy days were more in some mountain stations. Over the past 56 years, annual number of consecutive cold days decreased mainly in most parts of western China and eastern China. Consecutive thunderstorm days decreased in most parts of China. The trend of consecutive hot days, snowfall days and foggy days was not significant in most parts of China, and that of consecutive rainstorm days was not significant in almost the entire China. 展开更多
关键词 severe weathers consecutive days DISTRIBUTION TREND China
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Analysis of the Change Trends of Temperature and Frost-free Period in Xingtai in Recent 53 Years 被引量:2
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作者 CHENG Xiao-hui Xingtai Meteorological Administration in Hebei Province,Xingtai 054000,China 《Meteorological and Environmental Research》 CAS 2011年第7期38-40,共3页
[Objective] The changes trend of temperature and frost-free period in Xingtai in recent 53 years were studied.[Method] According to the climate data of Xingtai City and Nangong County in 1958-2010,the changes trend of... [Objective] The changes trend of temperature and frost-free period in Xingtai in recent 53 years were studied.[Method] According to the climate data of Xingtai City and Nangong County in 1958-2010,the changes trend of the temperature,the first and the last frost day,and the frost-free days in Xingtai were studied.The characteristics of the changes of temperature and frost-free days in Xingtai in recent 53 years were studied.[Result] No matter in city or countryside,the annual average temperature was increasing.The climate tendency rates in Xingtai and Nangong were about 0.5 and 0.2 ℃/10 a respectively.Especially,since 1996,the annual average temperature increasing trend was about 1.0 ℃/10 a.The average temperature of the four seasons was also climbing and was similar to the increasing span of the annual average temperature.The annual average temperature increasing span was the largest in winter.And the increase of the annual average temperature in winter was the largest and the increase of the annual average temperature was caused by the increase of the average temperature in winter.The urban annual average temperature was obviously higher than that of the countryside,which reflected the characteristics of tropical island effect.No matter in the city or the countryside,the early frost day,final frost day and frost-free day showed same tendency,namely,the delay of early frost day,advance of final-frost day,extension of frost-free day;the day of urban early frost was late than that of the countryside,and the final frost day was earlier than that of the countryside,the frost-free days were longer than that of countryside and indirectly influenced by urban heat effect.[Conclusion] The study provided theoretical basis for the development and application of thermal resources in Xingtai. 展开更多
关键词 Xingtai region TEMPERATURE frost-free period Trend analysis China
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Quantifying the attribution of model bias in simulating summer hot days in China with IAP AGCM 4.1 被引量:4
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作者 LIN Zhao-Hui YU Zheng +1 位作者 ZHANG He WU Cheng-Lai 《Atmospheric and Oceanic Science Letters》 CSCD 2016年第6期436-442,共7页
Using lAP AGCM simulation results for the period 1961-2005, summer hot days in China were calculated and then compared with observations. Generally, the spatial pattern of hot days is reasonably reproduced, with more ... Using lAP AGCM simulation results for the period 1961-2005, summer hot days in China were calculated and then compared with observations. Generally, the spatial pattern of hot days is reasonably reproduced, with more hot days found in northern China, the Yangtze and Huaihe River basin, the Chuan-Yu region, and southern Xinjiang. However, the model tends to overestimate the number of hot days in the above-mentioned regions, particularly in the Yangtze and Huaihe River basin where the simulated summer-mean hot days is 13 days more than observed when averaged over the whole region, and the maximum overestimation of hot days can reach 23 days in the region. Analysis of the probability distribution of daily maximum temperature (Trnax) suggests that the warm bias in the model-simulated Tmax contributes largely to the overestimation of hot days in the model. Furthermore, the discrepancy in the simulated variance of the Tmax distribution also plays a non- negligible role in the overestimation of hot days. Indeed, the latter can even account for 22% of the total bias of simulated hot days in August in the Yangtze and Huaihe River basin. The quantification of model bias from the mean value and variability can provide more information for further model improvement. 展开更多
关键词 Hot days variance inprobability distribution bias attribution modelevaluation IAP AGCM
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Load-forecasting method for IES based on LSTM and dynamic similar days with multi-features 被引量:5
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作者 Fan Sun Yaojia Huo +3 位作者 Lei Fu Huilan Liu Xi Wang Yiming Ma 《Global Energy Interconnection》 EI CSCD 2023年第3期285-296,共12页
To fully exploit the rich characteristic variation laws of an integrated energy system(IES)and further improve the short-term load-forecasting accuracy,a load-forecasting method is proposed for an IES based on LSTM an... To fully exploit the rich characteristic variation laws of an integrated energy system(IES)and further improve the short-term load-forecasting accuracy,a load-forecasting method is proposed for an IES based on LSTM and dynamic similar days with multi-features.Feature expansion was performed to construct a comprehensive load day covering the load and meteorological information with coarse and fine time granularity,far and near time periods.The Gaussian mixture model(GMM)was used to divide the scene of the comprehensive load day,and gray correlation analysis was used to match the scene with the coarse time granularity characteristics of the day to be forecasted.Five typical days with the highest correlation with the day to be predicted in the scene were selected to construct a“dynamic similar day”by weighting.The key features of adjacent days and dynamic similar days were used to forecast multi-loads with fine time granularity using LSTM.Comparing the static features as input and the selection method of similar days based on non-extended single features,the effectiveness of the proposed prediction method was verified. 展开更多
关键词 Integrated energy system Load forecast Long short-term memory Dynamic similar days Gaussian mixture model
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Chemical characterization of size-resolved aerosols in four seasons and hazy days in the megacity Beijing of China 被引量:20
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作者 Kang Sun Xingang Liu +7 位作者 Jianwei Gu Yunpeng Li Yu Qu Junling An Jingli Wang Yuanhang Zhang Min Hu Fang Zhang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2015年第6期155-167,共13页
Size-resolved aerosol samples were collected by MOUDI in four seasons in 2007 in Beijing. The PM10 and PM1.8mass concentrations were 166.0 ± 120.5 and 91.6 ± 69.7 μg/m^3, respectively,throughout the measure... Size-resolved aerosol samples were collected by MOUDI in four seasons in 2007 in Beijing. The PM10 and PM1.8mass concentrations were 166.0 ± 120.5 and 91.6 ± 69.7 μg/m^3, respectively,throughout the measurement, with seasonal variation: nearly two times higher in autumn than in summer and spring. Serious fine particle pollution occurred in winter with the PM1.8/PM10 ratio of 0.63, which was higher than other seasons. The size distribution of PM showed obvious seasonal and diurnal variation, with a smaller fine mode peak in spring and in the daytime. OM(organic matter = 1.6 × OC(organic carbon)) and SIA(secondary inorganic aerosol) were major components of fine particles, while OM, SIA and Ca^2+were major components in coarse particles. Moreover, secondary components, mainly SOA(secondary organic aerosol) and SIA,accounted for 46%-96% of each size bin in fine particles, which meant that secondary pollution existed all year. Sulfates and nitrates, primarily in the form of(NH4)2SO4, NH4NO3, Ca SO4, Na2SO4 and K2SO4, calculated by the model ISORROPIA II, were major components of the solid phase in fine particles. The PM concentration and size distribution were similar in the four seasons on non-haze days, while large differences occurred on haze days, which indicated seasonal variation of PM concentration and size distribution were dominated by haze days. The SIA concentrations and fractions of nearly all size bins were higher on haze days than on non-haze days, which was attributed to heterogeneous aqueous reactions on haze days in the four seasons. 展开更多
关键词 Chemical components Size resolved aerosols Seasonal variation Haze day Beijing
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