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temporal and spatial characteristics of Rainstorm during the Crops Growth Period in North China Region

Meteorological and Environmental Research 2010年第4期1卷 92-96,101页

作者：叶彩华侯双双姜会飞高静田璐北京市气候中心北京100089 中国农业大学资源与环境学院北京100094

By using the daily precipitation data from 1961 to 2005 in North China region,the temporal and spatial distribution characteristics of rainstorm process occurrence and the rainstorm intensity during the crops growth period were *** results showed that the rainstorm intensity and the rainstorm process during the crops growth period in North China region both had the obvious annual fluctuations and era variation *** the rainstorm and heavy rainstorm occurred in North China region every year,the annual variations were great,and the variation coefficients respectively reached 36.9% and 53.1%.The torrential rain occurred once in every 4-5 years,and the rainstorm process occurred once in every 11 *** the torrential rain and rainstorm process occurred in fewer years,their annual fluctuations were more *** peak value zones of rainstorm intensity which was greater and the rainstorm process which occurred frequently were in the *** 1999,the rainstorm intensity and the rainstorm process were in low value zone of historical stage from 1961 to ***,the 1970s-1990s was between high value and low value,and the rainstorms in different intensities which weren't synchronous happened in the *** addition,the spatial distribution of annual average rainstorm days presented the tendency which increased obviously from northwest to southeast in Northern China,and the variation coefficient of rainstorm days presented the tendency which increased gradually from southeast to ***,the more the annual average rainstorm days are,the smaller the variation coefficient is,and vice *** statistics results also showed that precipitation in North China had obvious positive correlation relationship with the rainstorm days.

关键词： temporal and spatial characteristics Growth period Rainstorm Rainstorm process Precipitation China

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A Review of Seasonal Hydrogen Storage Multi-Energy Systems Based on temporal and spatial characteristics

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Journal of Renewable Materials 2021年第11期9卷 1823-1842页

作者： Yuchen Cao Yongwen Yang Xianglong Zhao Qifen Li The College of Energy and Mechanical Engineering Shanghai University of Electric PowerShanghai200090China

The temporal and spatial characteristics of seasonal hydrogen storage will play a very important role in the coupling of multi-energy *** essay believes that there are several key issues worth noting in the seasonal hydrogen storage coupled multi-energy system,namely,hydrogen storage methods,coupling models,and benefit *** research,this article innovatively divides seasonal hydrogen storage into two types:space transfer hydrogen storage technology and time transfer physical property conversion hydrogen storage *** sort out the two most typical seasonal hydrogen storage multi-energy system application scenarios and their hydrogen storage unit ***,it is shown that hydrogen storage methods should be selected according to different periods of time and regions,and the benefits should be evaluated before they can be used in *** review study is applicable to the process of coupling seasonal hydrogen storage in multi-energy *** energy is used as an intermediate energy link for the selection,evaluation and modeling of the optimal selection and rational utilization.

关键词： temporal and spatial characteristics multi-energy system hydrogen storage technology modeling

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Comparison of temporal and spatial characteristics of Ozone Pollution at Ground Level in the Eastern China

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Chinese Journal of Population,Resources and Environment 2006年第3期4卷 51-57页

作者： Liu Houfeng1,2 1. Shandong Normal University, Jinan 250014, China 2. Chinese Research Academe of Environmental Sciences, Beijing 100012, China Shandong Normal University Jinan 250014 China Chinese Research Academe of Environmental Sciences Beijing 100012 China

Monitoring data from ozone（O3） automatic stations in three typical cities with different climatic areas in the southern and northern parts of eastern China are used to analyze temporal and spatial characteristics of ozone pollution at ground level. The results show that ozone pollution level has distinct regional differences and the concentration in the suburbs is higher than that in the urban areas. The seasonal variation of ozone concentration in different climatic areas is greatly affected by the variation of precipitation. Ozone concentration in Shenyang and Beijing , in the temperate zone, has one perennial peak concentration, occurring in early summer, May or June. Ozone concentration in Guangzhou, in sub-tropical zone, has two peak values year round. The highest values occur in October and the secondary high value in June. The ozone season in the south is longer than that in the north. The annual average daily peak value of ozone concentrations in different climates usually occur around 3 pm. The diurnal variation range of ozone concentration declines with the increase of latitude. Ozone concentration does not elevate with the increase of traffic flow. Ozone concentration in Guangzhou has a distinct reverse relation to CO and NOx. This complicated non-linearity indicates that the equilibrium of ozone photochemical reaction has regional differences. Exceeding the rate of Beijing＇s lh ozone concentration is higher than that of Guangzhou, whereas the average 8h ozone level is lower than that of Guangzhou, indicating that areas in low latitude are more easily affected by moderate ozone concentrations and longer exposure. Thus, China should work out standards for 8h ozone concentration.

关键词： ozone temporal and spatial characteristics 8h concentrations weekly variation

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THE temporal and spatial characteristics OF MOISTURE BUDGETS OVER ASIAN AND AUSTRALIAN MONSOON REGIONS

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Journal of Tropical Meteorology 2002年第2期8卷 113-120页

作者：乔云亭罗会邦简茂球 Departmentofatmosphericsciences ZhongshanUniversity

Apparent moisture sink and water vapor transport flux are calculated by using NCAR/NCEP reanalyzed daily data for water vapor and wind fields at various levels from 1980 to *** the aid of EOF analysis method,temporal and spatial characteristics of moisture budgets over Asian and Australian monsoon regions are *** results show that there is apparent seasonal transition of moistrue sink and water vapor transport between Asian monsoon region and Australian monsoon *** winter,the Asian monsoon region is a moisture source,in which three cross-equatorial water vapor transport channels in the 'continent bridge',at 80°E and 40°E～50° transport water vapor to the Australian monsoon region and southern Indian Ocean which are moistrue *** summer,Australian Monsoon region anmd southern Indian Ocean are moistrue sources and by the three cross-equatorial transport channels water vapor is transport to the Asian monsoon region which is a moisture *** spring and autumn,ITCZ is the main moisture sink and there is no apparent water vapor transport between Asian monsoon region and Australian monsoon region.

关键词： Asian-Australian monsoon region moisture budgets temporal and spatial characteristics

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Study on temporal and spatial characteristics of Climate Variation in Hebei Area during 1956-2007

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Meteorological and Environmental Research 2011年第9期2卷 13-16,19页

作者： ZHANG Ke-hui LIU Jian-feng LIU Fang-yuan XIAO Si-rong Institute of Geographical Sciences Hebei Academy of SciencesShijiazhuang 050011China

[Objective] The research aimed to study temporal and spatial characteristics of climate variation in Hebei area during 1956-2007. [Method] Based on the data from 23 weather stations evenly distributed over Hebei area (included Beijing and Tianjin) during 1956-2007, by using statistical analytic method, the temporal and spatial variation characteristics of main meteorological factors (temperature and precipitation, etc.) in the area were analyzed. The variation fact and evolution rule of climate in the area in 52 years were discussed. [Result] In Hebei area during 1956-2007, the annual and four-season temperatures both presented wavy rise trends. The temperature increment in winter was the maximum, contributing the most to the annual temperature elevation in this area. The temperatures in the whole district all presented rise trends, and the variation difference had regularity. The annual and four-season rainfalls both had large fluctuation amplitudes, following different linear variation trends. The annual rainfall overall presented wavy decrease trends. The spatial difference of rainfall variation was significant. The rainfalls in the whole district all presented decrease trends. The decrease amplitude presented low-high-low pattern from the northeast to the southwest. The potential evaporation capacity over the whole district was the highest in the 1960s, and decreased ever since instead of increasing with the temperature. The potential evaporation capacities of each season also presented decline trends. Except in Fengning and Yuxian, the evaporation capacities of other stations in the whole district all presented decline trends. The relative humidity slightly decreased as time, with the exception of Chengde, Qinhuangdao and Nangong. The sunshine hours had a clear decrease trends. [Conclusion] The research provided scientific basis for realizing regional sustainable development, improving ecological environment and people’s life quality.

关键词： Climate variation temporal and spatial characteristics Hebei area China

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Motor imagery-based EEG signals classification by combining temporal and spatial deep characteristics

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International Journal of Intelligent Computing and Cybernetics 2020年第4期13卷 437-453页

作者： Li Xiaoling Gongqing College of Nanchang University GongqingchengChina

Purpose-In order to improve the weak recognition accuracy and robustness of the classification algorithm for brain-computer interface(BCI),this paper proposed a novel classification algorithm for motor imagery based on temporal and spatial characteristics extracted by using convolutional neural networks(TSCNN)***/methodology/approach-According to the proposed algorithm,a five-layer neural network model was constructed to classify the electroencephalogram(EEG)***,the author designed a motor imagery-based BCI experiment,and four subjects were recruited to participate in the experiment for the recording of EEG ***,after the EEG signals were preprocessed,the temporal and spatial characteristics of EEG signals were extracted by longitudinal convolutional kernel and transverse convolutional kernels,***,the classification of motor imagery was completed by using two fully connected ***-To validate the classification performance and efficiency of the proposed algorithm,the comparative experiments with the state-of-the-arts algorithms are applied to validate the proposed *** results have shown that the proposed TS-CNN model has the best performance and efficiency in the classification of motor imagery,reflecting on the introduced accuracy,precision,recall,ROC curve and F-score ***/value-The proposed TS-CNN model accurately recognized the EEG signals for different tasks of motor imagery,and provided theoretical basis and technical support for the application of BCI control system in the field of rehabilitation exoskeleton.

关键词： Convolutional neural network Motor imagery Brain-computer interface EEG signal temporal and spatial characteristics

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Analysis on temporal and spatial Variation characteristics of Potential Evapotranspiration in Guizhou Province

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Agricultural Science & Technology 2014年第4期15卷 635-641页

作者：楚勤方兰安军陈栋为犹珀玉刘发勇肖小林贵州师范大学地理与环境科学学院贵州贵阳550001 中国水电顾问集团贵阳勘测设计研究院贵州贵阳550001

[Objective] The aim was to analyze temporal and spatial variation charac- teristics of potential evapotranspiration in Guizhou Province. [Method] According to information from 19 meteorological stations of Guizhou Province from 1960 to 2007, with the formulas of optimizational Penman-Monteith and SEBAL net radiation mod- el, the reference crop evapotranspiration ETo was calculated. Also with the spatial interpolation method of Arcgis 9.3, climate tendency rate statistics, K-M test, wavelet analysis and so on, the related regional differentiation and spatial and temporal change characteristics between meteorological factors from each monitoring station and ETo were analyzed. [Result] The results show that the correlation of potential evapotranspiration and meteorological factors in Guizhou Province demonstrates re- gional differentiation; there was no direct connection between the correlation of po- tential evapotranspiration and meteorological factors and the amount of meteorologi- cal factors in the year; there were 3 cycles in potential evapotranspiration, namely, 1 year, 5 years and 10 years, with 3 mutation points, respectively, in 1965, 1984 and 1999, mainly affected by air temperature, precipitation and solar radiation. [Conclusion] The research is of great significance in developing irrigation approach- es, adjusting agricultural structure and ecological construction.

关键词： Potential evapotranspiration Penman-Monteith formula temporal and spatial characteristics Guizhou Province

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spatial-temporal characteristics of a Temperate-Glacier's Active-Layer Temperature and Its Responses to Climate Change: A Case Study of Baishui Glacier No. 1, Southeastern Tibetan Plateau

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Journal of Earth Science 2014年第4期25卷 727-734页

作者： Shijin Wang Jiankuo Du Yuanqing He State Key Laboratory of Cryospheric Sciences Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

Based on the historical documents and measured data from the active-layer temperature （ALT） at A, B and C locations （4 670, 4 720 and 4 770 m a.s.l.） on Baishui Glacier No. 1, southeastern Tibetan Plateau, this paper analyzed spatial-temporal characteristics of ALT and its relationship with air temperature, and revealed the response of the active layer ice temperature towards climate change in the monitoring period. The results showed that the influence of air temperature on the active-layer ice temperature had a hysteresis characteristic on the upper of ablation zone and the lag period in- creased gradually with the altitude elevating. The decrease amplitude of ALT in the accumulation pe- riod was far below its increase magnitude in the ablation period. At the same time, the mean glacier ice temperatures at 10 m depth （T10） in A, B and C profile were obviously higher than most of glaciers previously studied. Measured data also showed that the mean ALT increased by 0.24℃ in 0.5-8.5 m depth of the C profile during 28 years from July 11, 1982 to July 10, 2009.

关键词： temperate-glacier active-layer temperature temporal and spatial characteristics climate change.

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Calculation of Agricultural Production Efficiency Based on a Three-stage Data Envelopment Analysis Model and Analysis of the spatial-temporal characteristics: A Case Study of the Yangtze River Economic Belt

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Meteorological and Environmental Research 2021年第5期12卷 68-76,83页

作者： Wenjun ZHUO Haiyang CUI School of Economics Guizhou UniversityGuiyang 550025China

In response to the strategic call for the " Great Protection" of the Yangtze River Economic Belt and to fulfill the important historical tasks assigned by the state to the provinces and cities of the area,the Yangtze River Economic Belt is adjusting the agricultural industry structure,optimizing the input-output ratio,and ensuring stable and sustainable agricultural production. Based on the combination of the three-stage Data Envelopment Analysis( DEA) model and cluster analysis,this study examined the Yangtze River Economic Belt from 2008 to 2018 to measure its agricultural production efficiency and to analyze its temporal and spatial characteristics. Studies showed that exogenous environmental factors significantly( P temporal and spatial differences. These included:(1) after excluding environmental factors,the overall agricultural production efficiency of the Yangtze River Economic Zone had improved. Sichuan Province and Jiangsu Province were at the forefront of efficiency,whereas the agricultural production efficiency of Shanghai had declined obviously.(2) The agricultural production efficiency of the Yangtze River Economic Belt varied year by year,with fluctuating development. The middle reaches of the Yangtze River had advanced agricultural production efficiency more than the upstream and downstream regions,and the agricultural production efficiency of the individual provinces did not match their economic and social development.(3) Increases in labor,land,irrigation,and other input factors increased agriculture production efficiency,and there was no correlation between fiscal investment,per capita gross domestic product( GDP) and agricultural production efficiency,while the disaster-affected area had a significantly negative impact on agricultural production efficiency.

关键词： Agricultural production efficiency Three-stage Date Envelopment Analysis temporal and spatial characteristics Yangtze River Economic Belt

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A Detail Investigation on the Antarctic Wind Energy

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中国海洋工程:英文版 2023年第4期37卷 698-708页

作者： WANG Kai-shan WU Di ZHENG Chong-wei TAO Gui-sheng LI Wei GAO Yuan-bo YU Yue WU Kai Dalian Naval Academy Dalian 116018China Marine Resources and Environment Research Group on the Maritime Silk Road Dalian 116018China Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai) Zhuhai 519082China

The scientific development of wind energy based on local conditions is conducive to the urgent energy demand and environmental protection of Antarctic *** this study,the ERA5 reanalysis data are used to evaluate the wind energy resources in the Antarctic region.A series of key indicators,such as wind power density,effective wind speed occurrence,energy level occurrence and stability,are comprehensively considered by using climate statistical analysis methods to analyze the temporal and spatial distribution characteristics of Antarctic wind energy *** results show that the Antarctic region contains abundant wind energy resources,which benefits the construction of scientific research *** superior areas are the Southern Ocean and the coast of the East Antarctica,followed by the Transantarctic Mountains,the coast of the Bellingshausen Sea and Amundsen *** areas have advantages in terms of wind power density(500-2500 W/m2),effective wind speed occurrence(80%-90%),energy level occur-rence(60%-90%)and stability(Cv:0.6-1,Mv:1.2-1.8,Sv:0.8-1.2).The Antarctic’s wind energy resources in wind power density,effective wind speed occurrence and energy level occurrence in autumn and winter are better than those in summer,while the coefficient of variation in summer is worse than that in autumn and winter.

关键词： Antarctic wind energy resource evaluation temporal and spatial characteristics

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