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
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
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
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
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
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
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
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
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
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
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
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
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
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
Mixed use has been extensively applied as an urban planning principle and hinders the study of single urban functions.To address this problem,it is worth decomposing the mixed use.Inspired by the concept of spectral u...Mixed use has been extensively applied as an urban planning principle and hinders the study of single urban functions.To address this problem,it is worth decomposing the mixed use.Inspired by the concept of spectral unmixing in remote sensing applications,this paper proposes a framework for mixed-use decomposition based on big geo-data.Mixeduse decomposition in terms of human activities differs from traditional land use research,and it is more reasonable to infer the actual urban function of land.The framework consists of four steps,namely temporal activity signature extraction,urban function base curve extraction,mixeduse decomposition,and result validation.First,the temporal activity signatures(TASs)of each zone are extracted as the proxy of human activity patterns.Second,the diurnal TASs of routine activities are extracted as urban function base curves(i.e.endmembers).Third,a linear decomposition model is used to decompose the mixed use and obtain multiple results(urban function composition,dynamic activity proportions,and the mixing index).Finally,result validation strategies are concluded.This framework offers method extensibility and has few requirements for the input data.It is validated by means of a case study of Beijing,based on a social media check-in dataset.展开更多
We introduce a concept of episode referring to a time interval in the development of a dynamic phenomenon that is characterized by multiple time-variant attributes.A data structure representing a single episode is a m...We introduce a concept of episode referring to a time interval in the development of a dynamic phenomenon that is characterized by multiple time-variant attributes.A data structure representing a single episode is a multivariate time series.To analyse collections of episodes,we propose an approach that is based on recognition of particular patterns in the temporal variation of the variables within episodes.Each episode is thus represented by a combination of patterns.Using this representation,we apply visual analytics techniques to fulfil a set of analysis tasks,such as investigation of the temporal distribution of the patterns,frequencies of transitions between the patterns in episode sequences,and co-occurrences of patterns of different variables within same episodes.We demonstrate our approach on two examples using real-world data,namely,dynamics of human mobility indicators during the COVID-19 pandemic and characteristics of football team movements during episodes of ball turnover.展开更多
Prey adjust their antipredator behavioral tactics to minimize the risk of an encounter with predators.Spatiotemporal responses of prey to pred-ators have been reported,but the nature of antipredator response is not ub...Prey adjust their antipredator behavioral tactics to minimize the risk of an encounter with predators.Spatiotemporal responses of prey to pred-ators have been reported,but the nature of antipredator response is not ubiquitous and it is the object of increasing interest,especially consid-ering the recent recovery of large carnivores in Europe,and the potential for behavioral antipredator responses to elicit consequences at the ecosystem level.We have tested multiple antipredator responses by fallow deer Dama dama to wolf Canis lupus in a Mediterranean protected area recently recolonized by this apex predator.Through intensive camera trapping,we tested for temporal and spatial association between predator and prey,and we have also studied deer vigilance in forest habitats where focal observations are usually impossible.Wolf detection rates were spatially associated with those of fallow deer.Accordingly,no evidence was found for fallow deer avoiding sites with higher predator detection rates.Temporal activity patterns were significantly different between the 2 species,with the wolf being mainly nocturnal whereas fallow deer was active especially during daylight.A comparison with a preliminary study strongly suggests an increase in the diurnal activity of fallow deer along with the stabilization of wolf presence in the area.Both the rate and the duration of vigilance of female fallow deer increased with the local frequency of wolf activity.We suggest an antipredator response based on temporalrather than spatialavoidance,as well as increasedvigilance.展开更多
This paper analyses the features and dynamic changes of the spatial layout of air transportation utilization among different provinces in China. It makes use of data for the airport throughput and socio-economic devel...This paper analyses the features and dynamic changes of the spatial layout of air transportation utilization among different provinces in China. It makes use of data for the airport throughput and socio-economic development of every province throughout the country in the years 2006 and 2015, and employs airport passenger and cargo throughput per capita and per unit of GDP as measures of regional air transportation utilization, which is significant for refining indicators of regional air transportation scale and comparing against them. It also analyzes the spatial differences of coupling between the regional air transportation utilization indicators and the key influencing factors on regional air transportation demand and utilization, which include per capita GDP, urbanization rate, and population density. Based on these key influencing factors, it establishes a multiple linear regression model to conduct forecasting of each province's future airport passenger and cargo throughput as well as throughput growth rates. The findings of the study are as follows:(1) Between 2006 and 2015, every province throughout the country showed a trend of year on year growth in their airport passenger and cargo throughput per capita. Throughput per capita grew fastest in Hebei, with a rise of 780%, and slowest in Beijing, with a rise of 38%. Throughput per capita was relatively high in western and southeastern coastal regions, and relatively low in northern and central regions. Airport passenger and cargo throughput per unit of GDP showed growth in provinces with relatively slow economic development, and showed negative growth in provinces with relatively rapid economic development. Throughput per unit of GDP grew fastest in Hebei, rising 265% between 2006 and 2015, and Hunan had the fastest negative growth, with a fall of 44% in the same period. Southwestern regions had relatively high throughput per unit of GDP, while in central, northern, and northeastern regions it was relatively low.(2) Strong correlation exists between airport passenger and cargo throughput per capita and per capita GDP, urbanization rate, and population density. Throughput per capita has positive correlation with per capita GDP and urbanization rate in all regions, and positive correlation with population density in most regions. Meanwhile, there is weak correlation between airport passenger and cargo throughput per unit of GDP and per capita GDP, urbanization rate, and population density, with positive correlation in some regions and negative correlation in others.(3) Between 2015 and 2025, it is estimated that all provinces experience a trend of rapid growth in their airport passenger and cargo throughput. Inner Mongolia and Hebei will see the fastest growth, rising221% and 155%, respectively, while Yunnan, Sichuan, and Hubei will see the slowest growth, with increases of 62%, 63%, and 65%, respectively.展开更多
基金supported by the National Natural Science Foundation of China(grant no.61573328).
文摘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.
基金the NN SFC(Grant No. 49733110 ),the Min-istry of L and and Resources of China (Project No. 2 0 0 0 10 10 2 0 6 ,2 0 0 0 10 10 2 0 2 ) ,and theostdoctoral Science Foundation of China
文摘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
基金supported by the National Natural Science Foundation of China(Nos.31900204,32071671,32030071)the Postdoctoral Research Foundation of China(grant no.2019M652674)the Fundamental Research Funds for the Central Universities(grant no.CCNU22LJ003).
文摘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.
基金supported by the National Natural Science Foundation of China(Grant No.31770429 and 32071492)the National Defense Basic Scientific Research Project of China(Grant No.C019220023).
文摘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.
基金Authors acknowledged the Canadian Institute for Health Research(CIHR)Children's Hospital Research Institute of Manitoba(CHRIM)Foundation+1 种基金Visual and Automated Disease Analytics(VADA)graduate training program of Natural Sciences and Engineering Research Council of Canada(NSERC)for providing the funding opportunities to conduct this research.
文摘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.
基金Key Project of National Science and Technology Supporting Program, No.2006038053001 Key Project of National Natural Science Foundation of China, No.40535026 Environment Protection and Public Welfare Project of Ministry of Science and Technology, No.08L80370AJ
文摘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.
基金supported by the Medical Research Center Program(2015R1A5A2009124)through the National Research Foundation of Korea(NRF)funded by the Ministry of Science,ICT and Future Planning
文摘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,
文摘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.
文摘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.
基金Sponsored by the Project for the Philosophy and Social Science Research of Hubei Provincial Department of Education in 2021 (21Q049)Innovation and Entrepreneurship Project for University Students of Changjiang University in 2021 (Yz2021325)。
文摘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.
文摘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.
基金Under the auspices of Natural Science Foundation of Heilongjiang Province(No.LH2019D008)Youth Fund for Humanities and Social Sciences of the Ministry of Education(No.19YJC630177)+1 种基金Innovative Youth Talent Cultivation Plan of Heilongjiang Provincial Universities(No.UNPYSCT-2018194)Human Civilization and Social Science Supportive Program for Excellent Young Scholars of Harbin Normal University(No.SYQ2014-06)。
文摘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.
基金was funded by the Jiangxi Provincial Social Science Foundation“the 14th Five-Year Plan”(2021)regional project(21DQ44)Science and Technology Research Project of Jiangxi Provincial Department of Education(GJJ210723)+1 种基金the Doctoral Research Initiation fund of East China University of Technology(DHBK2019184)the Graduate Innovation Fund of East China University of Technology(DHYC-202123).
文摘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”.
基金supported by the European IST-FP6 Project OPUCE under Grant No. 34101the National Natural Science Foun- dation of China under Grant No. 60573117+1 种基金the National Basic Research 973 Program of China under Grant No. 2007CB310804the Australian Research Council under Grant No. LP0775188.
文摘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.
基金This work was supported by the National Key R&D Program of China[grant number 2017YFB0503602]the National Natural Science Foundation of China[grant numbers 41830645,41625003,and 41771425]Strategic Priority Research Program of the Chinese Academy of Sciences[grant number XDA19040402].
文摘Mixed use has been extensively applied as an urban planning principle and hinders the study of single urban functions.To address this problem,it is worth decomposing the mixed use.Inspired by the concept of spectral unmixing in remote sensing applications,this paper proposes a framework for mixed-use decomposition based on big geo-data.Mixeduse decomposition in terms of human activities differs from traditional land use research,and it is more reasonable to infer the actual urban function of land.The framework consists of four steps,namely temporal activity signature extraction,urban function base curve extraction,mixeduse decomposition,and result validation.First,the temporal activity signatures(TASs)of each zone are extracted as the proxy of human activity patterns.Second,the diurnal TASs of routine activities are extracted as urban function base curves(i.e.endmembers).Third,a linear decomposition model is used to decompose the mixed use and obtain multiple results(urban function composition,dynamic activity proportions,and the mixing index).Finally,result validation strategies are concluded.This framework offers method extensibility and has few requirements for the input data.It is validated by means of a case study of Beijing,based on a social media check-in dataset.
基金supported by Federal Ministry of Education and Research of Germany and the state of North-Rhine Westphalia as part of the Lamarr Institute for Machine Learning and Artificial Intelligence(Lamarr22B)EU in projects SoBigData++and CrexData,and by DFG within priority research program SPP VGI(project EVA-VGI).
文摘We introduce a concept of episode referring to a time interval in the development of a dynamic phenomenon that is characterized by multiple time-variant attributes.A data structure representing a single episode is a multivariate time series.To analyse collections of episodes,we propose an approach that is based on recognition of particular patterns in the temporal variation of the variables within episodes.Each episode is thus represented by a combination of patterns.Using this representation,we apply visual analytics techniques to fulfil a set of analysis tasks,such as investigation of the temporal distribution of the patterns,frequencies of transitions between the patterns in episode sequences,and co-occurrences of patterns of different variables within same episodes.We demonstrate our approach on two examples using real-world data,namely,dynamics of human mobility indicators during the COVID-19 pandemic and characteristics of football team movements during episodes of ball turnover.
基金supported by the Maremma Regional Park Agency.Additional financial support was provided by the German Society for Mammalian Biology(DGS Project Funding 2018)BE was supported by a grant from the Ministry of Agriculture of the Czech Republic(Institutional support MZE-RO0718)and by an Erasmus+scholarship from the Czech University of Life Sciences Prague.
文摘Prey adjust their antipredator behavioral tactics to minimize the risk of an encounter with predators.Spatiotemporal responses of prey to pred-ators have been reported,but the nature of antipredator response is not ubiquitous and it is the object of increasing interest,especially consid-ering the recent recovery of large carnivores in Europe,and the potential for behavioral antipredator responses to elicit consequences at the ecosystem level.We have tested multiple antipredator responses by fallow deer Dama dama to wolf Canis lupus in a Mediterranean protected area recently recolonized by this apex predator.Through intensive camera trapping,we tested for temporal and spatial association between predator and prey,and we have also studied deer vigilance in forest habitats where focal observations are usually impossible.Wolf detection rates were spatially associated with those of fallow deer.Accordingly,no evidence was found for fallow deer avoiding sites with higher predator detection rates.Temporal activity patterns were significantly different between the 2 species,with the wolf being mainly nocturnal whereas fallow deer was active especially during daylight.A comparison with a preliminary study strongly suggests an increase in the diurnal activity of fallow deer along with the stabilization of wolf presence in the area.Both the rate and the duration of vigilance of female fallow deer increased with the local frequency of wolf activity.We suggest an antipredator response based on temporalrather than spatialavoidance,as well as increasedvigilance.
基金National Natural Science Foundation of China,No.41171433Philosophy and Social Science Foundation of China,No.16BJY039
文摘This paper analyses the features and dynamic changes of the spatial layout of air transportation utilization among different provinces in China. It makes use of data for the airport throughput and socio-economic development of every province throughout the country in the years 2006 and 2015, and employs airport passenger and cargo throughput per capita and per unit of GDP as measures of regional air transportation utilization, which is significant for refining indicators of regional air transportation scale and comparing against them. It also analyzes the spatial differences of coupling between the regional air transportation utilization indicators and the key influencing factors on regional air transportation demand and utilization, which include per capita GDP, urbanization rate, and population density. Based on these key influencing factors, it establishes a multiple linear regression model to conduct forecasting of each province's future airport passenger and cargo throughput as well as throughput growth rates. The findings of the study are as follows:(1) Between 2006 and 2015, every province throughout the country showed a trend of year on year growth in their airport passenger and cargo throughput per capita. Throughput per capita grew fastest in Hebei, with a rise of 780%, and slowest in Beijing, with a rise of 38%. Throughput per capita was relatively high in western and southeastern coastal regions, and relatively low in northern and central regions. Airport passenger and cargo throughput per unit of GDP showed growth in provinces with relatively slow economic development, and showed negative growth in provinces with relatively rapid economic development. Throughput per unit of GDP grew fastest in Hebei, rising 265% between 2006 and 2015, and Hunan had the fastest negative growth, with a fall of 44% in the same period. Southwestern regions had relatively high throughput per unit of GDP, while in central, northern, and northeastern regions it was relatively low.(2) Strong correlation exists between airport passenger and cargo throughput per capita and per capita GDP, urbanization rate, and population density. Throughput per capita has positive correlation with per capita GDP and urbanization rate in all regions, and positive correlation with population density in most regions. Meanwhile, there is weak correlation between airport passenger and cargo throughput per unit of GDP and per capita GDP, urbanization rate, and population density, with positive correlation in some regions and negative correlation in others.(3) Between 2015 and 2025, it is estimated that all provinces experience a trend of rapid growth in their airport passenger and cargo throughput. Inner Mongolia and Hebei will see the fastest growth, rising221% and 155%, respectively, while Yunnan, Sichuan, and Hubei will see the slowest growth, with increases of 62%, 63%, and 65%, respectively.