期刊文献+
共找到25篇文章
< 1 2 >
每页显示 20 50 100
Elevational and temporal patterns of pollination success in distylous and homostylous buckwheats(Fagopyrum)in the Hengduan Mountains
1
作者 Ling-Yun Wu Shuang-Quan Huang Ze-Yu Tong 《Plant Diversity》 SCIE CAS CSCD 2024年第5期661-670,共10页
Reproductive strategies of sexually dimorphic plants vary in response to the environment.Here,we ask whether the sexual systems of Fagopyrum species(i.e.,selfing homostylous and out-crossing distylous)represent distin... Reproductive strategies of sexually dimorphic plants vary in response to the environment.Here,we ask whether the sexual systems of Fagopyrum species(i.e.,selfing homostylous and out-crossing distylous)represent distinct adaptive strategies to increase reproductive success in changing alpine environments.To answer this question,we determined how spatial and temporal factors(e.g.,elevation and peak flowering time)affect reproductive success(i.e.,stigmatic pollen load)in nine wild Fagopyrum species(seven distylous and two homostylous)among 28 populations along an elevation gradient of 1299-3315 m in the Hengduan Mountains,southwestern China.We also observed pollinators and conducted hundreds of hand pollinations to investigate inter/intra-morph compatibility,self-compatibility and pollen limitation in four Fagopyrum species(two distylous and two homostylous).We found that Fagopyrum species at higher elevation generally had bigger flowers and more stigmatic pollen loads;lateflowering individuals had smaller flowers and lower pollen deposition.Stigmatic pollen deposition was more variable in distylous species than in homostylous species.Although seed set was not pollenlimited in all species,we found that fruit set was much lower in distylous species,which rely on frequent pollinator visits,than in homostylous species capable of autonomous self-pollination.Our findings that pollination success increases at high elevations and decreases during the flowering season suggest that distylous and homostylous species have spatially and temporally distinct reproductive strategies related to environment-dependent pollinator activity. 展开更多
关键词 Biodiversity hotspot Elevation gradient FAGOPYRUM Stigmatic pollen load temporal pattern
下载PDF
Geostatistical Analysis on the Temporal Patterns of the Yellow Rice Borer, Tryporyza incertulas 被引量:2
2
作者 YUAN Zhe-ming WANG Zhi Hu Xiang-yue 《Rice science》 SCIE 2005年第3期207-212,共6页
In order to comprehend temporal pattern of the larvae population of the yellow rice borer, Tryporyza incertulas, and provide valuable information for its forecast model, the data series of the population for each gene... In order to comprehend temporal pattern of the larvae population of the yellow rice borer, Tryporyza incertulas, and provide valuable information for its forecast model, the data series of the population for each generation and the over-wintered larvae from 1960 to 1990 in Dingcheng District, Changde City, Hunan Province, were analyzed with geostatistics. The data series of total number, the 1st generation, the 3rd generation and the over-wintered larvae year to year displayed rather better autocorrelation and prediction. The data series of generation to generation, the 2nd generation and the 4th generation year to year, however, demonstrated poor autocorrelation, especially for the 4th generation, whose autocorrelation degree was zero. The population dynamics of the yellow rice borer was obviously intermittent. A remarkable cycle of four generations, one year, was observed in the population of generation to generation. Omitting the certain generation or interposing the over-wintered larvae only resulted in a less or slight change of autocorrelation of the whole data series generation to generation. Crop system, food, climate and natural enemies, therefore, played more important roles in regulating the population dynamics than base number of the larvae. The basic techniques of geostatistics applied in analyzing temporal population dynamics were outlined. 展开更多
关键词 Tryporyza incertulas GEOSTATISTICS temporal patterns POPULATION FORECAST
下载PDF
Temporal patterns of dengue epidemics:The case of recent outbreaks in Kaohsiung 被引量:1
3
作者 Mattia Sanna Ying-Hen Hsieh 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2017年第3期275-279,共5页
Objective:To investigate whether major dengue outbreaks in the last two decades in Kaohsiung follow a precise temporal pattern.Methods:Government daily lab-confirmed dengue case data from three major dengue outbreaks ... Objective:To investigate whether major dengue outbreaks in the last two decades in Kaohsiung follow a precise temporal pattern.Methods:Government daily lab-confirmed dengue case data from three major dengue outbreaks occurring during the last two decades in Kaohsiung in2002,2014 and 2015,is utilized to compute the corresponding weekly cumulative percentage of total case numbers.We divide each of the three time series data into two periods to examine the corresponding weekly cumulative percentages of case numbers for each period.Pearson’s correlation coefficient was calculated to compare quantitatively the similarity between the temporal patterns of these three years.Results:Three cutoff points produce the most interesting comparisons and the most different outcomes.Pearson’s correlation coefficient indicates quantitative discrepancies in the similarity between temporal patterns of the three years when using different cutoff points.Conclusions:Temporal patterns in 2002 and 2014 are comparatively more similar in early stage.The 2015 outbreak started late in the year,but ended more like the outbreak in 2014,both with record-breaking number of cases.The retrospective analysis shows that the temporal dynamics of dengue outbreaks in Kaohsiung can strongly vary from one year to another,making it difficult to identify any common predictor. 展开更多
关键词 DENGUE Kaohsiung temporal pattern Cumulative percentage Pearson's correlation coefficient
下载PDF
Adaptive temporal patterns of echolocation and flight behaviors used to fly through varied-sized windows by 2 species of high duty cycle bats
4
作者 Jianan Ding Yu Zhang +4 位作者 Fujie Han Tingting Jiang Jiang Feng Aiqing Lin Ying Liu 《Current Zoology》 SCIE CAS CSCD 2023年第1期32-40,共9页
As actively sensing animals guided by acoustic information, echolocating bats must adapt their vocal–motor behavior to various environmentsand behavioral tasks. Here, we investigated how the temporal patterns of echo... As actively sensing animals guided by acoustic information, echolocating bats must adapt their vocal–motor behavior to various environmentsand behavioral tasks. Here, we investigated how the temporal patterns of echolocation and flight behavior were adjusted in 2 species of batswith a high duty cycle (HDC) call structure, Rhinolophus ferrumequinum and Hipposideros armiger, when they flew along a straight corridorand then passed through windows of 3 different sizes. We also tested whether divergence existed in the adaptations of the 2 species. Both H.armiger and R. ferrumequinum increased their call rates by shortening the pulse duration and inter-pulse interval for more rapid spatial samplingof the environment when flying through smaller windows. Bats produced more sonar sound groups (SSGs) while maintaining a stable proportion of calls that made up SSGs during approaches to smaller windows. The 2 species showed divergent adjustment in flight behavior across3 different window sizes. Hipposideros armiger reduced its flight speed to pass through smaller windows while R. ferrumequinum increasedits flight speed. Our results suggest that these 2 species of HDC bats adopt similar acoustic timing patterns for different tasks although theyperformed different flight behaviors. 展开更多
关键词 echolocating bats environmental clutter flight trajectory sensory adaptation sonar temporal pattern
原文传递
Spatial and Temporal Patterns of Supply and Demand Balance of Water Supply Services in the Dongjiang Lake Basin and Its Beneficiary Areas 被引量:2
5
作者 徐洁 肖玉 +1 位作者 李娜 王浩 《Journal of Resources and Ecology》 CSCD 2015年第6期386-396,共11页
Water-related ecosystem services is a hot topic in ecological research. Water supply services are crucial to regional water cycles and water quantity balance. The Dongjiang Lake basin is a national priority river basi... Water-related ecosystem services is a hot topic in ecological research. Water supply services are crucial to regional water cycles and water quantity balance. The Dongjiang Lake basin is a national priority river basin in China where ecological compensation pilot programs concerning water resources and water supply services are top priorities for ecosystem service protection. We analyzed spatial and temporal patterns associated with generation and use of water supply services in the Dongjiang Lake basin using the In VEST model, socio-economic data and water resource data. We found that between 1995 and 2010, water yield in the Dongjiang Lake basin and its beneficiary areas increased before declining, varying 9350–12 400 m3 ha-1 y-1; average water yield peaked in 2000. The spatial distribution patterns of water yield during these years are similar, progressively decreasing from upstream to downstream with a remarkable reduction in surrounding areas of city clusters. Average water consumption of the basin and its beneficiary areas ranged from 2900–4450 m3 ha-1 y-1 between 1995 and 2010; the spatial distribution patterns of water consumption during these years are similar, dropping gradually from urban construction land to its surroundings with a stronger gradient between urban and rural areas. More water was consumed on both banks and surroundings of the lake. From 1995 to 2010, water supply fell short of demand for urban construction land and its proximity as well as areas along the lake. Water supply services were able to satisfy needs in other regions. The Changsha-Zhuzhou-Xiangtan city cluster suffers from the most strained water supply. 展开更多
关键词 ecosystem services water supply services Dongjiang Lake supply and demand balance spatial and temporal patterns
原文传递
Analysis on the Spatio-temporal Patterns of Water Conservation Services in Beijing 被引量:12
6
作者 XU Jie XIAO Yu XIE Gaodi 《Journal of Resources and Ecology》 CSCD 2019年第4期362-372,共11页
The shortage of water resources is a key factor limiting the sustainable development of the economy and society in Beijing. This study analysed the spatiotemporal patterns of Beijing’s water conservation services(WCS... The shortage of water resources is a key factor limiting the sustainable development of the economy and society in Beijing. This study analysed the spatiotemporal patterns of Beijing’s water conservation services(WCS) based on the water balance equation at multiple scales, including city, main functional areas and key districts and counties, determined the differences in the water conservation amount among different land cover types and investigated the reasons for the spatiotemporal differences in the water conservation amount. The results indicated that:(1) compared to 2005, water conservation amount increased substantially in 2010. However, the overall water conservation capacity was low.(2) Among the various land cover types in Beijing, the average water conservation capacity decreased in the following order: wetland, forest, grassland, cropland, bare land and artificial surface.(3) The average water conservation amount in the main functional areas of Beijing varied substantially and was positive only in the ecological conservation area(ECA).(4) The water conservation capacity of each district and county varied substantially within ECA, among which the contribution of the forest in Miyun District, Huairou District and Pinggu District was the highest. The changes in the spatiotemporal patterns of Beijing’s WCS were the synthetic effects of changes in the land covers and meteorological conditions. This study is helpful in achieving the sustainable utilization of water resources in Beijing. 展开更多
关键词 water conservation services spatial and temporal patterns water balance BEIJING
原文传递
Regional and temporal patterns of influenza: Application of functional data analysis
7
作者 Azizur Rahman Depeng Jiang 《Infectious Disease Modelling》 2021年第1期1061-1072,共12页
Background:The accurate estimation of temporal patterns of influenza may help in utilizing hospital resources and guiding influenza surveillance.This paper proposes functional data analysis(FDA)to improve the predicti... Background:The accurate estimation of temporal patterns of influenza may help in utilizing hospital resources and guiding influenza surveillance.This paper proposes functional data analysis(FDA)to improve the prediction of temporal patterns of influenza.Methods:We illustrate FDA methods using the weekly Influenza-like Illness(ILI)activity level data from the U.S.We propose to use the Fourier basis function for transforming discrete weekly data to the smoothed functional ILI activities.Functional analysis of variance(FANOVA)is used to examine the regional differences in temporal patterns and the impact of state's political orientation.Results:The ILI activity has a very distinct peak at the beginning and end of the year.There are significant differences in average level of ILI activities among geographic regions.However,the temporal patterns in terms of the peak and flat time are quite consistent across regions.The geographic and temporal patterns of ILI activities also depend on the political make-up of states.The states affiliated with Republicans had higher ILI activities than those affiliated with Democrats across the whole year.The influence of political party affiliation on temporal pattern is quite different among geographic regions.Conclusions:Functional data analysis can help us to reveal the temporal variability in average ILI levels,rate of change in ILI levels,and the effect of geographical regions.Consideration should be given to wider application of FDA to generate more accurate estimates in public health and biomedical research. 展开更多
关键词 Functional data analysis Functional ANOVA Influenza-like illness temporal patterns Political orientation
原文传递
The temporal and spatial patterns and potential evaluation of China's energy resources development 被引量:8
8
作者 MA Beibei LU Chunxia +1 位作者 ZHANG Lei CHENG Xiaoling 《Journal of Geographical Sciences》 SCIE CSCD 2010年第3期347-356,共10页
The issue of China's energy supply security is not only the key problem which af- fects China's rapid and sustainable development in the 21st century, but also the one which international attention focuses on. Based... The issue of China's energy supply security is not only the key problem which af- fects China's rapid and sustainable development in the 21st century, but also the one which international attention focuses on. Based on the notable characteristic of spatial imbalance between energy production and consumption in China, this paper takes the evolution of China's primary energy resources development(excluding hydropower) from 1949 to 2007 as the study object, with the aim to sum up the evolutive characteristics and laws of China's energy resources development in the past nearly 60 years. Then, based on comprehensive considerations of coal's, oil's and natural gas's basic reserves, qualities, geological conditions production status, and ecological service function of every province, this paper adopts development potential index (DP)to evaluate the development potential of every province's en- ergy resources, and divide them into different ranks. Conclusions are drawn as follows: (1) Generally speaking, China's gross energy production was increasing in waves from 1949 to 2007. From the viewpoint of spatial patterns, China's energy resources development has shown a characteristic of "concentrating to the north and central areas, and evolving from linear-shaped to "T-shaped" pattern gradually since 1949. (2) The structure evolution of China's energy resources development in general has shown a trend of "coal proportion is dominant but decreasing, while oil and gas proportions are increasing" since 1949. (3) At the provincial scale, China's energy resources development potential could be divided into large, sub-large, general and small ranks, four in all. In the future, the spatial pattern of China's energy production will evolve from "T-shaped" to "R-shaped pattern". These conclusions will help to clarify the temporal and spatial characteristics and laws of China's energy resources development, and will be beneficial for China to design scientific and rational energy development strategies and plans, coordinate spatial imbalance of energy production and consumption, ensure national energy supply, avoid energy resources waste and disorderly development, and promote regional sustainable development under the globalization back-ground with changeful international energy market. 展开更多
关键词 energy resources development temporal and spatial patterns potential evaluation China
下载PDF
THE TEMPORAL AND SPATIAL PATTERNS OF ENVIRONMENTAL RISK EVENTS IN THE PAST 30 YEARS IN SHENYANG CITY
9
作者 Bi Jun Tang Yijian Zhang Shen(Institute of Geography, CAS, Beijing 100101People’s Republic of China)Wang Huadong(Institute of Environmental Sciences, Beijing Normal University, Beijing 100875People’s Republic of China) 《Journal of Geographical Sciences》 SCIE CSCD 1995年第1期76-86,共11页
The index of Risk Frequency (RF) and other relative indices are used to analyze the temporal and spatial patterns of environmental riskevents in the past 30 years in Shenyang city. The results show that thereexists si... The index of Risk Frequency (RF) and other relative indices are used to analyze the temporal and spatial patterns of environmental riskevents in the past 30 years in Shenyang city. The results show that thereexists significant difference of the RFs between periods of 1966-1977 and1978-1991 (t=7.353**, t0.01=2.807). During the past 30 years, there areno significant changes of the spatial patterns of the environmental risk,while the proportions of environmental risk among the districts are extremely different. In Shenyang city, there exists a series of high riskenterprises, and the chemical industry is the one with highest risk. 展开更多
关键词 environmental risk events temporal and spatial patterns risk frequency
下载PDF
Temporal pattern mining from user-generated content 被引量:1
10
作者 Adnan Ali Jinlong Li +1 位作者 Huanhuan Chen Ali Kashif Bashir 《Digital Communications and Networks》 SCIE CSCD 2022年第6期1027-1039,共13页
Faster internet, IoT, and social media have reformed the conventional web into a collaborative web resulting in enormous user-generated content. Several studies are focused on such content;however, they mainly focus o... Faster internet, IoT, and social media have reformed the conventional web into a collaborative web resulting in enormous user-generated content. Several studies are focused on such content;however, they mainly focus on textual data, thus undermining the importance of metadata. Considering this gap, we provide a temporal pattern mining framework to model and utilize user-generated content's metadata. First, we scrap 2.1 million tweets from Twitter between Nov-2020 to Sep-2021 about 100 hashtag keywords and present these tweets into 100 User-Tweet-Hashtag (UTH) dynamic graphs. Second, we extract and identify four time-series in three timespans (Day, Hour, and Minute) from UTH dynamic graphs. Lastly, we model these four time-series with three machine learning algorithms to mine temporal patterns with the accuracy of 95.89%, 93.17%, 90.97%, and 93.73%, respectively. We demonstrate that user-generated content's metadata contains valuable information, which helps to understand the users' collective behavior and can be beneficial for business and research. Dataset and codes are publicly available;the link is given in the dataset section. 展开更多
关键词 Social media analysis Collaborative computing Social data Twitter data temporal patterns mining Dynamic graphs
下载PDF
Temporal and Spatial Evolution of Lakes in the Bashang Plateau for Nearly Recent 30 Years
11
作者 Xiujuan Li Sugai Gao +2 位作者 Wenli Li Guifu Qiu Zhiyuan Tian 《Journal of Water Resource and Protection》 CAS 2022年第10期698-708,共11页
Lakes are important ecological water sources in the Bashang Plateau. Its expansion or shrinkage directly affects the ecological security of the plateau and its surrounding areas. In this study, Landsat images from 198... Lakes are important ecological water sources in the Bashang Plateau. Its expansion or shrinkage directly affects the ecological security of the plateau and its surrounding areas. In this study, Landsat images from 1984 to 2015 were selected to monitor the area of lakes in the Bashang Plateau and to analyze the spatiotemporal evolution and driving forces of lakes in the Bashang Plateau. The results showed that there were 47 lakes in the Bashang Plateau in 2015, with a total area of 37.63 km2, mainly distributed in the central and western regions of the region. From 1984 to 2015, the lakes in Bashang Plateau showed a shrinking trend. At the same time, there are obvious stage differences in lake changes. During 1984-1996, the number of lakes increased by 99 and the total area increased by 124.43 km2. From 1996 to 2015, the number of lakes decreased by 142, and the total area decreased by 183.96 km2. Before 1996, climate change was the dominant factor. However, the shrinkage of lakes after 1996 is the result of climate change and human activities. Among them, the large-scale planting of water consuming crops such as vegetables is the main human activity mode leading to lake shrinkage. This study will help to understand the expansion and contraction factors of the Bashang Plateau lakes in Hebei province and provide a reference for the future protection and management of the lakes. 展开更多
关键词 Bashang Plateau Lake Area Spatial and temporal patterns Evolution Driving Force
下载PDF
Temporal and Spatial Differentiation of Cultural Heritage in Jingzhou Area of National Great Site Protection and Its Influencing Factors
12
作者 CAI Tianqing GUO Xiaohua +1 位作者 LU Chuan XIONG Shunyao 《Journal of Landscape Research》 2022年第3期36-42,48,共8页
In the context of territorial spatial planning,the overall coordinated protection has become a consensus in the field of cultural heritage protection,and the study on the spatial and temporal pattern of trans-regional... In the context of territorial spatial planning,the overall coordinated protection has become a consensus in the field of cultural heritage protection,and the study on the spatial and temporal pattern of trans-regional cultural heritage is of great significance to the overall protection.Based on the cultural relics protection units in Jingzhou area of national great site protection,the temporal and spatial distribution characteristics and influencing factors of cultural heritage resources were studied with the help of ArcGIS.The data show that on the whole,the cultural heritage in Jingzhou area of national great site protection presented the time series of “a large span,more at two ends” and the spatial distribution pattern of “one main,two secondary and three cores”.Cultural heritage in different historical periods had the characteristics of differentiated regional aggregation.The formation of the spatial pattern of different types of cultural heritage was closely related to the local historical and cultural background.Cultural heritage was affected by rivers,terrain,transportation,land,culture and other factors.It was mainly distributed along rivers in areas with little topographic fluctuation and low altitudes.The development and construction of cultural heritage sites were weak,and the ecological foundation was poor.However,the traffic accessibility was good,and the cultural heritage was deep.The research results are expected to provide a scientific basis for guiding the large site protection area to strengthen the integrated protection of cultural resources. 展开更多
关键词 National great site protection Spatial and temporal patterns Influencing factor GIS Cultural heritage Jingzhou
下载PDF
Spatial and Temporal Pattern of Urban Smart Development in China and Its Driving Mechanism 被引量:3
13
作者 CHEN Xiaohong WEI Luyao ZHANG Haifeng 《Chinese Geographical Science》 SCIE CSCD 2018年第4期584-599,共16页
Smart urban development is an inevitable choice, and is essential to overall strength improvement. It is important to explore an urban smart development path which unites smart growth with driving shrinkage perfectly ... Smart urban development is an inevitable choice, and is essential to overall strength improvement. It is important to explore an urban smart development path which unites smart growth with driving shrinkage perfectly in forming scientific and sustainable development concept and responding to new normal strategic opportunities. Based on statistic data of 294 prefecture-level cities and above in China from 2000 to 2015, we analyzed spatial and temporal evolution of urban smart development in China by constructing a dynamic fitting model of urban land expansion, population growth, and economic development as well as the coefficient of variation of urban smart development(CVSD). Further efforts were then made to consider differential distribution regularity of urban smart development so as to understand the driving mechanisms of heterogeneous classification of urban smart development in China from different scales and scale variation. Our results indicate that: 1) the disordered growth tendency of urban cities in China is overall well controlled in the middle, and late research and it mainly presented a doublet coexistence of shrinkage disordered cities and smart developing cities. It is particularly obvious that Northeast China and East China have regarded shrinkage disordered cities and smart developing cities as main development tendency separately. 2) Areas with basic stability and relative variation were relatively dispersed across the time period, but the proportion was far beyond areas with significant variation. It demonstrates a relative equilibrium spatial and temporal differential evolution pattern of prefecture-level cities and above in China, except for Tongling, Lanzhou and Chaoyang. 3) prefecture-level cities and above in China are mostly characterized by shrinkage disordered and smart development classification under the background of different scale and scale variation from 2000–2015; however, the spatial resonance relation is not obvious. 4) There are many interaction factors forming an important driving mechanism in developing the spatial and temporal pattern of urban smart development in China, including natural geographical factors, industrial structure adjustment, human capital radiation, regional traffic accessibility, and government decision-making intervention. 展开更多
关键词 urban smart development spatial and temporal differential pattern driving mechanism interaction factors China
下载PDF
The brain activation pattern of the medial temporal lobe during chewing gum: a functional MRI study 被引量:2
14
作者 Youn-Hee Choi Woo Hyuk Jang +5 位作者 Sang-Uk Im Keun-Bae Song Hee-Kyung Lee Han Do Lee You Sung Seo Sung Ho Jang 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第5期812-814,共3页
The human brain is known to be influenced by environmental stimuli(Feeney et al.,1982;Kaplan,1988).Therefore,research on the brain activation pattern by external stimuli has been an important topic in neuroscience(... The human brain is known to be influenced by environmental stimuli(Feeney et al.,1982;Kaplan,1988).Therefore,research on the brain activation pattern by external stimuli has been an important topic in neuroscience(Kaplan,1988).Chewing gum has been known to have a positive effect on cognition,including alertness,attention,cognitive processing speed, 展开更多
关键词 MRI The brain activation pattern of the medial temporal lobe during chewing gum a functional MRI study
下载PDF
Spatiotemporal differentiation of coupling and coordination relationship of production-living-ecological space in Yellow River Basin
15
作者 LIU He LI Song-bo ZUO Xiao-yuan 《Ecological Economy》 2022年第3期162-180,共19页
Based on combing the existing research on the production-living-ecological space,the paper quantitatively analyzes the evaluation system-development level-temporal and spatial evolution,future trend-influencing factor... Based on combing the existing research on the production-living-ecological space,the paper quantitatively analyzes the evaluation system-development level-temporal and spatial evolution,future trend-influencing factors of the production-living-ecological functions coupling and coordination in the Yellow River Basin from 2009 to 2018.Through multi-scale analysis and comparison,the paper tries to identify problem areas and put forward corresponding measures.The research results show that:(1)The coupling and coordination degree of the production-living-ecological functions in the Yellow River Basin both show an upward trend,and its future growth trend is relatively slow.(2)The spatial-temporal differential characteristics of the coordinated development level of the production-living-ecological functions are obvious,and gradually develop towards the direction of benign resonance in time,showing a spatial distribution pattern of“high in the northeast and low in the southwest”.(3)There is a big difference in the level of coordinated development of the production-living-ecological functions,and the coordination degree of the“production-living”function is the lowest.(4)Scientific and technological investment,economic development level,government capacity,and urbanization level have a significant positive impact on the spatial effect of the coordinated development of the production-living-ecological functions of the Yellow River Basin,and the same factor has different effects on different regions. 展开更多
关键词 production-living-ecological functions coupling and coordination spatial and temporal pattern trend forecast Yellow River Basin
下载PDF
LATE MESOZOIC SUBDUCTION PROCESS BENEATH SOUTHEASTERN CHINA AS REVEALEDBY THE SPATIAL- TEMPORAL PATTERN OFMAGMATISM
16
作者 WANG Yang 1, DENG Jin fu 1, WANG Ji yang 2 and XIONG Liang ping 2 (1. Division of Petrology, China University of Geosciences, Beijing 100083, China 2. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China) 《Geotectonica et Metallogenia》 2001年第1期68-70,共3页
Southeastern China covers an extensive area from the lowerreaches of the Yangtze Riverto the southeast coastof China mainland.One of its main geological features isthe extensiveJura- Cretaceous (Yanshanian) magmatism ... Southeastern China covers an extensive area from the lowerreaches of the Yangtze Riverto the southeast coastof China mainland.One of its main geological features isthe extensiveJura- Cretaceous (Yanshanian) magmatism and related metallogenesis. Recently,some re-searchers advocate the mantle plume model as an explanation,but all of their evidences artoo ambiguous.Meanwhile,the seaward convex shape of the SE China coastline,which isdominantly composed of Jura- Cretaceous batholiths and volcanic strata,implies thatit was aconvergent margin between SE China continent and the palaeo- Pacific plate during the lateMesozoic era.Fora betterunderstanding on the relation among magmatism,tectonic regimeand dynamics,the spatial- temporal pattern of late Mesozoic (180 - 90 Ma) igneous rocks isconstructed by nearly2 0 0 isotope age valuesfrom literatures.Among these age values,mostwere obtained by Rb- Sr isochron method,and others from zircon U- Pb or40  Ar- 3 展开更多
关键词 LATE MESOZOIC SUBDUCTION PROCESS BENEATH SOUTHEASTERN CHINA AS REVEALEDBY THE SPATIAL temporal PATTERN OFMAGMATISM AS
下载PDF
Temporal and Spatial Distribution Patterns of Grain Crops in the West Liaohe River Basin 被引量:3
17
作者 封志明 杨玲 杨艳昭 《Journal of Resources and Ecology》 CSCD 2014年第3期244-252,共9页
Here,we quantitatively determine temporal and spatial distribution characteristics of main grain crops in the West Liaohe River basin,Inner Mongolia,China,from 2000 to 2010 based on MODIS remote sensing data and NDVI ... Here,we quantitatively determine temporal and spatial distribution characteristics of main grain crops in the West Liaohe River basin,Inner Mongolia,China,from 2000 to 2010 based on MODIS remote sensing data and NDVI time series information for the years 2000,2005 and 2010.Phenological calendars and a decisionmaking tree extraction model were also used to obtain spatial distribution information of spring maize,spring wheat and soybean.We found that in 2010,the sown area of the main grain crops in the West Liaohe River basin was 11 965.08km2,of which,the sown area for spring maize accounted for 92.28%and was concentrated in the lower reaches of the region.Spring wheat accounted for 3.14% and was mainly in the middle reaches.Soybean accounted for 4.58% and was predominantly in the upper reaches.From 2000 to 2005,the sown area of these grain crops in the West Liaohe River basin grew by 29.77%,mainly in the lower reaches: spring maize grew by 38.99%,spring wheat by 39.04% and soybean by 21.27%.From 2005 to 2010,growth in the sown area of these crops was slow(5.18% growth) and mainly in the lower reaches of the basin.The sown area of spring maize increased,but decreased for both spring wheat and soybean. 展开更多
关键词 MODIS grain crops temporal and spatial distribution pattern West Liaohe River basin MAIZE SOYBEAN wheat.
原文传递
Habitat quality assessment of mining cities based on InVEST model—a case study of Yanshan County,Jiangxi Province 被引量:3
18
作者 Yanan Li Linghua Duo +2 位作者 Ming Zhang Jingyuan Yang Xiaofei Guo 《International Journal of Coal Science & Technology》 EI CAS CSCD 2022年第2期245-254,共10页
The assessment of the spatiotemporal evolution of habitat quality caused by land use changes can provide a scientifc basis for the ecological protection and green development of mining cities.Taking Yanshan County as ... The assessment of the spatiotemporal evolution of habitat quality caused by land use changes can provide a scientifc basis for the ecological protection and green development of mining cities.Taking Yanshan County as an example of a typical mining city,this article discussed the spatial pattern and evolution characteristics of habitat quality in 2000 and 2018 based on the ArcGIS platform and the InVEST model.The conclusions are as below:from 2000 to 2018,the area of farmland and construction land changed the most in the study area.Among them,the area of farmland decreased by 3.48%,and the area of industrial and mining land and construction land increased by 53.25%.Areas of low,relatively low and high habitat quality expanded,and areas of medium and relatively high habitat quality shrank,which is closely related to the distribution of land use.The areas with high habitat degradation degrees appear around cities,mining areas and watersheds,while the areas with low habitat degradation degrees are mainly distributed in the southern woodland.The distribution of cold and hot spots in the habitat quality distribution of Yanshan County presents a pattern of“hot in the south and cold in the north”.The results are of great signifcance to the precise implementation of ecosystem management decisions in mining cities and the creation of a landscape pattern of“beautiful countrysides,green cities,and green mines”. 展开更多
关键词 InVEST model Habitat quality Land use change temporal and spatial pattern Mining city
下载PDF
Coupling and Coordination Characteristics and Influencing Factors of the Livable Environment System for the Elderly in China
19
作者 CHEN Xiaohong ZHANG Mingxuan +3 位作者 WANG Ying XU Xiaoqing LIU Shuang MA Lingyu 《Chinese Geographical Science》 SCIE CSCD 2022年第6期1052-1068,共17页
The construction of a livable environment for the elderly is an important measure to address the challenges of aging and improve their livelihood and well-being.Based on China’s national conditions and combined with ... The construction of a livable environment for the elderly is an important measure to address the challenges of aging and improve their livelihood and well-being.Based on China’s national conditions and combined with the actual development needs of the cities,it is of great significance to explore the coupling and coordination characteristics and influencing factors within the livable environment system for the elderly for the coordination and stable development.This article was based on the three subsystems of’living service environment,socioeconomic environment and ecological livable environment’,following the research framework of’process-pattern-trend-impact’,constructs an evaluation index system for the livable environment for the elderly.Entropy weight-TOPSIS evaluation model,coupling coordination degree model,center of gravity and standard deviation ellipse model and the geographic detector model were used starting from the evolution of coupling coordination types to study the spatial and temporal pattern and dynamic trend characteristics and influencing factors of internal coupling coordination types in the livable environment system for the elderly from2010 to 2019.The results showed that:1)The coordinated development of life service environment system and ecological livable environment system(LE)and socioeconomic environment system and ecological livable environment system(SE)in the livable environment for the elderly decreased from the intermediate coordination level coordination areas to the low-level quality improvement and optimization areas:coordinated transition type.The overall development level of life service environment system and socioeconomic environment system(LS)was low,and it was always at a low level.2)The coupling degree of livable environment system for the elderly was high,the coupling coordination type shown a gradually decreasing layer structure with Zhejiang,Beijing and Guangdong high-level leading demonstration areas as the axis belt.3)The coupling coordination center of the elderly livable environment system was located in Henan,and the standard deviation ellipse was distributed in the northeast-southwest direction.The development center and the ellipse of the high-level leading demonstration areas and the intermediate coordination level areas were concentrated in the central and eastern regions,while the low-level coordination areas for improving quality and efficiency are mainly located in the western region.4)Urban development,green facilities,infrastructure,government macroscopic regulation and control,economic stimulus,and housing construction were all important factors affecting the coordinated development of the livable environment system for the elderly,exerting a varying degree of effect on the level of coordinated development of various types of systems. 展开更多
关键词 livable environment system the elderly coupling coordination degree spatial and temporal pattern dynamic trend influencing factors China
下载PDF
Synthesizing Service Composition Models on the Basis of Temporal Business Rules 被引量:4
20
作者 喻坚 韩燕波 +3 位作者 韩军 金岩 Paolo Falcarin Maurizio Morisio 《Journal of Computer Science & Technology》 SCIE EI CSCD 2008年第6期885-894,共10页
Transformational approaches to generating design and implementation models from requirements can bring effectiveness and quality to software development. In this paper we present a framework and associated techniques ... Transformational approaches to generating design and implementation models from requirements can bring effectiveness and quality to software development. In this paper we present a framework and associated techniques to generate the process model of a service composition from a set of temporal business rules. Dedicated techniques including path- finding, branching structure identification and parallel structure identification are used for semi-automatically synthesizing the process model from the semantics-equivalent Finite State Automata of the rules. These process models naturally satisfy the prescribed behavioral constraints of the rules. With the domain knowledge encoded in the temporal business rules, an executable service composition program, e.g., a BPEL program, can be further generated from the process models. A running example in the e-business domain is used for illustrating our approach throughout this paper. 展开更多
关键词 service composition composition synthesis behavioral model temporal patterns
原文传递
上一页 1 2 下一页 到第
使用帮助 返回顶部