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1.
Many aspects of an animal’s ecology are associated with activity patterns. One important and controversial one is in the predator/prey relationship. We examined temporal patterns of coyotes (Canis latrans) and lagomorphs (Lepus californicus, Sylvilagus audobonii), their main prey in the Chihuahuan Desert. We test the hypothesis that a predator and prey will have non-random distribution of activity relative to each other; this non-random activity could be a substantial overlap or the lack of synchrony depending on the competing theories. We used GPS collars to track coyotes; we identified areas of activity and determined daily patterns. We installed lagomorph feeding stations and game cameras in coyote activity areas to assess lagomorph patterns. All three species were mainly crepuscular. Black-tail jackrabbits and Audubon’s cottontail rabbits had different hourly patterns of activity (P < 0.001). Activity peaks for jackrabbits occurred between 0400-0700 h, and 1800-2000 h. Cottontail rabbit activity peaks occurred between 0500-0700 h, and 1800-2000 h. The coyote evening activity peak was synchronous with lagomorph activity, but the morning peak occurred from 0700 to 1000. We found partial lack of synchrony in the activity patterns of the predator and its prey.  相似文献   

2.
A mechanistic understanding of human activity patterns lays a foundation for many applications. The majority of the current research aims to outline human activity patterns mainly from spatiotemporal perspectives (i.e., modeling human mobility patterns), lacking of understanding of the motivations behind behaviors. The aim of this study is to model and understand human activity patterns within urban areas using both spatiotemporal and cognitive psychology methods to measure both human behavior patterns and the underlying motivations . We first propose a framework that enables us to analyze the spatiotemporal patterns of urban human activities, infer the associated semantic patterns that represent the motivations driving human mobility choices and behaviors, and measure the similarity between human activities. We then construct a human activity network based on the similarity to depict human activity patterns. The framework is applied to a case study of Toronto, Canada, where geotagged tweets are used as a proxy for human activities to explore activity patterns. The analysis of the human activity network shows that 61% of tweeter users follow similar activity patterns. Our work provides a new tool for better understanding the way individuals interact with urban environments that could be applied\ to a variety of urban applications.  相似文献   

3.
The association between spatial patterns of retail activity and the spatial configuration of street networks was examined by means of the space syntax methodology in eight Israeli cities that represent two city types, characterized by different planning approaches and urban growth: (i) new towns, which were established according to a comprehensive city plan and modern planning concepts of “tree-like” hierarchical street networks and “neighborhood units”; (ii) older cities, where street networks and the spatial patterns of retail activity were formed incrementally during their growth. Unlike in older cities, retail activity in new towns concentrates in relatively less-accessible and intermediate locations. This is indicated by a weak correlation between retail activity and the street network’s Integration and Choice centrality measures. The comparison between Israeli cities illustrates the influence of urban growth and planning approaches on the formation of retail activity and its interaction with the structure of the street network.  相似文献   

4.
Many elements are known to affect the decision-making procedures that underlie time–space activity patterns. Yet, knowledge regarding the relations between these elements is lacking. In this article, a hierarchical structure of external and cognitive time–space behavioral influences is proposed based on the results of a field experiment. The experiment relied on an in situ sampling of stated and overt behaviors of visitors to a touristic site in northern Israel, using questionnaires and Global Positioning System loggers. Two experimental treatments were simultaneously applied during sampling, dividing the sample into four groups: Each participant received on entry one of two maps, designed according to different cartographical–cognitive approaches; new activity stations were placed during half of the sampling days, meaning that each participant was exposed to one of two possible spatial layouts. The behavioral patterns recorded expose each treatment's distinct behavioral effect along with its relative weight within the decision-making process, thus pointing toward a hierarchical structure.  相似文献   

5.
ABSTRACT

Individual activity patterns are influenced by a wide variety of factors. The more important ones include socioeconomic status (SES) and urban spatial structure. While most previous studies relied heavily on the expensive travel-diary type data, the feasibility of using social media data to support activity pattern analysis has not been evaluated. Despite the various appealing aspects of social media data, including low acquisition cost and relatively wide geographical and international coverage, these data also have many limitations, including the lack of background information of users, such as home locations and SES. A major objective of this study is to explore the extent that Twitter data can be used to support activity pattern analysis. We introduce an approach to determine users’ home and work locations in order to examine the activity patterns of individuals. To infer the SES of individuals, we incorporate the American Community Survey (ACS) data. Using Twitter data for Washington, DC, we analyzed the activity patterns of Twitter users with different SESs. The study clearly demonstrates that while SES is highly important, the urban spatial structure, particularly where jobs are mainly found and the geographical layout of the region, plays a critical role in affecting the variation in activity patterns between users from different communities.  相似文献   

6.
We studied how features of thermal resources affect the patterns of activity of predator (Callopistes maculatus) and its prey (Gyriosomus batesi and Gyriosomus subrugatus) during the phenomenon of the Flowering Desert in Chile. We predict that restrictions or variations in temperature affect mainly the activity of insects, and that this variation in the activity of insects affects the patterns of activity of the predator. The daily activity of the three species was bimodal, but both prey species disappear when temperatures exceed 40 °C. According to our results, the prey are thermoconformers to air and substrate temperature, whereas the predator is a thermoregulator to environmental conditions by their independence of air and substrate temperature.  相似文献   

7.
Tracking spatial and temporal trends of events (e.g. disease outbreaks and natural disasters) is important for situation awareness and timely response. Social media, with increasing popularity, provide an effective way to collect event-related data from massive populations and thus a significant opportunity to dynamically monitor events as they emerge and evolve. While existing research has demonstrated the value of social media as sensors in event detection, estimating potential time spans and influenced areas of an event from social media remains challenging. Challenges include the unstable volumes of available data, the spatial heterogeneity of event activities and social media data, and the data sparsity. This paper describes a systematic approach to detecting potential spatiotemporal patterns of events by resolving these challenges through several interrelated strategies: using kernel density estimation for smoothed social media intensity surfaces; utilizing event-unrelated social media posts to help map relative event prevalence; and normalizing event indicators based on historical fluctuation. This approach generates event indicator maps and significance maps explaining spatiotemporal variations of event prevalence to identify space-time regions with potentially abnormal event activities. The approach has been applied to detect influenza activity patterns in the conterminous US using Twitter data. A set of experiments demonstrated that our approach produces high-resolution influenza activity maps that could be explained by available ground truth data.  相似文献   

8.
Since the 1970s, activity diaries have been the principal source of data used by geographers and urban planners to capture human mobility patterns; however, memory recall requirements and participant burden are limiting features of this approach. While handheld GPS devices were initially used to simply validate activity diaries, the ubiquity of smartphones makes GPS-based technology a viable alternative for collecting human mobility data. This research visualises human mobility patterns using spatiotemporally GPS-rich traces collected from 24 participants during a pilot study of a new smartphone application—Wander. The results illustrate the utility of such data for capturing individuals’ multi-nodal activity spaces to better understand people–place interactions in the context of increasingly fluid and mobile lifestyles. Finally, we draw on our experiences of implementing this pilot study to discuss the benefits and limitations of this technology for its broader application in domains such as transportation planning, tourism management, and in the management of crime and disorder.  相似文献   

9.
The purpose of this paper is to examine changes in the spatial variance of mean monthly and daily temperatures that may have occurred during the period of historical records. The northern hemispheric lower-tropospheric satellite-based temperature records from 1979 to 1996 and the near-surface air temperature records from either 1947 to 1996 or 1897 to 1996 show relatively consistent temporal patterns with respect to spatial variance. Overall, the spatial variance in temperature anomalies has declined during the period of historical records; the interannual spatial variance levels in temperature anomalies are negatively related to mean hemispheric temperature. Both of these fundamental findings are consistent with model simulations for increasing atmospheric concentrations of greenhouse gases. It is further argued that these findings from the historical temperature records are consistent with a growing body of literature on reductions in cyclone activity in the Northern Hemisphere. [Key words: historical temperature patterns, spatial variance, greenhouse effect, climate change.]  相似文献   

10.
ABSTRACT

Datasets collecting the ever-changing position of moving individuals are usually big and possess high spatial and temporal resolution to reveal activity patterns of individuals in greater detail. Information about human mobility, such as ‘when, where and why people travel’, is contained in these datasets and is necessary for urban planning and public policy making. Nevertheless, how to segregate the users into groups with different movement and behaviours and generalise the patterns of groups are still challenging. To address this, this article develops a theoretical framework for uncovering space-time activity patterns from individual’s movement trajectory data and segregating users into subgroups according to these patterns. In this framework, individuals’ activities are modelled as their visits to spatio-temporal region of interests (ST-ROIs) by incorporating both the time and places the activities take place. An individual’s behaviour is defined as his/her profile of time allocation on the ST-ROIs she/he visited. A hierarchical approach is adopted to segregate individuals into subgroups based upon the similarity of these individuals’ profiles. The proposed framework is tested in the analysis of the behaviours of London foot patrol police officers based on their GPS trajectories provided by the Metropolitan Police.  相似文献   

11.
Debris flows are a major threat in many parts of the Alps, where they repeatedly cause severe damage to infrastructure and transportation corridors or even loss of life. Nonetheless, the spatial behavior of past debris-flow activity and the analysis of areas affected during particular events have been widely neglected in reconstructions so far. It was therefore the purpose of this study to reconstruct spatio-temporal patterns of past debris flows on a forested cone in the Swiss Alps (Bruchji torrent, Blatten, Valais). The analysis of past events was based on a detailed geomorphic map (1:1000) of all forms related to debris flows as well as on tree-ring series from 401 heavily affected trees (Larix decidua Mill. and Picea abies (L.) Karst.) growing in or next to deposits. The samples were analyzed and growth disturbances related to debris-flow activity assessed, such as tangential rows of traumatic resin ducts, the onset of reaction wood or abrupt growth suppression or release.In total, 960 growth disturbances were identified in the samples, belonging to 40 different event years between A.D. 1867 and 2005. In addition, the coupling of tree-ring data with the geomorphic map allowed reconstruction of eleven formerly active channels and spatial representation of individual events. Based on our results we believe that before 1935, debris flows preferentially used those channels located in the western part of the cone, whereas the eastern part of the cone remained widely unaffected. The spatial representation of the 40 events also allowed identification of five different spatial patterns for debris flows at the study site.  相似文献   

12.
广州市零售商业中心消费活动时变模式及其影响因素   总被引：4，自引：3，他引：1  
利用2016年在广州典型大型零售商业中心进行的客流量监测和居民消费行为问卷数据,分析基于客流时间变化的广州大型零售商业中心消费活动时变模式,构建多项Logistic回归模型,从消费者社会经济属性、消费活动特征和商业中心建成环境3方面探讨该时变模式的影响因素。结果显示：① 广州不同的大型零售商业中心内消费活动存在明显的时变特征差异,可分成稳定型、下午高峰型、傍晚高峰型和不规则波动型4类时变模式;② 这种时变模式受到消费者社会经济属性、消费活动特征和商业建成环境等变量的影响。其中,消费者社会经济属性和消费活动特征影响有限且影响差异较大,以稳定型为参照组,在广州居住时间、居住区位和家庭月收入等社会经济属性,以及消费结构、出行路径、交通方式和出行距离等消费活动特征能区分稳定型和下午高峰型商业中心,但只有在广州居住时间和出行距离、交通方式3个变量能显著地解释稳定型和傍晚高峰型商业中心的差异;建成环境是影响零售商业中心时变模式的首要因素,商业网点密度、用地混合度、公交与地铁站点密度、商业中心区位特征、到市中心距离等变量均对各个类型商业中心的形成作用显著。期望为城市零售商业中心的分类和评价提供一个新思路,为预测商业中心可能的消费活动时变模式、消费者属性和活动特征提供理论依据,对城市商业规划和商业中心开发运营有一定的现实指导意义。  相似文献   

13.
To what extent were Australian vegetation patterns in 1788 a product of human activity? Pollen and charcoal evidence which addresses this question is reviewed. I discuss the nature of the evidence, particularly the difficulties involved in establishing relationships between charcoal and fire history, and between fire history and human activity. I then address the broader question from the perspectives of both time and space by examining three key periods which might be expected to provide relevant evidence: (i) the time of initial human colonisation of the continent; (ii) the late Holocene, when Aboriginal population densities are thought to have increased substantially; and (iii) the last 200 years, when Aboriginal influences on the landscape have been mostly removed. Impacts are likely to have been different in different environments, with vegetation types vulnerable to fire showing the most marked changes. I conclude with a discussion of ways alternative interpretations have been utilised by competing groups in land management debates.  相似文献   

14.
申悦  罗雪瑶 《地理研究》2022,41(4):1152-1169
社会空间分异是城市研究的经典议题。在人类移动性不断增强的背景下,传统的基于居住空间汇总的社会空间分异测度方法表现出一定的局限性,对于居住空间外的日常活动空间隔离的探讨相对缺乏,对于不同活动和不同时段间分异格局差异的考虑有所不足。因此有必要从“基于人”的视角出发,探索社会空间分异测度的新方法,探讨不同时空间维度的社会分异格局。本研究基于上海市郊区10个典型镇的活动日志调查数据,构建“个体时空邻近指数”,聚焦户籍这一反映中国城市特征的重要维度,以不同户籍类型人群之间的分异程度为研究对象,分析其时空间特征,并对结果进行可视化。研究表明：上海市不同户籍人群在活动、时间和空间维度上存在明显的社会空间分异。本研究创新了基于活动空间的社会空间分异测度方法,从活动与时空间结合的视角探讨了户籍维度的社会空间分异,为更好的理解在中国大城市日益凸显的社会空间分异问题提供了新的视角。  相似文献   

15.
We examined the impact of temporal dependence between patterns of error in classified time-series imagery through a simulation modeling approach. This research extended the land-cover-change simulation model we previously developed to investigate: (1) the assumption of temporal independence between patterns of error in classified time-series imagery; and (2) the interaction of patterns of change and patterns of error in a post-classification change analysis. In this research, the thematic complexity of the classified land-cover maps was increased by increasing the number of simulated land-cover classes. Simulating maps with increased categorical resolution permitted the incorporation of: (1) higher-order, more complex spatial and temporal interactions between land-cover classes; and (2) patterns of error that better reproduce the complex error interactions that often occur in time-series classified imagery. The overall modeling framework was divided into two primary components: (1) generation of a map representing true change; and (2) generation of a suite of change maps that had been perturbed by specific patterns of error. All component maps in the model were produced using simulated annealing, which enabled us to create a series of map realizations with user-defined spatial and temporal patterns. Comparing the true map of change to the error-perturbed maps of change using accuracy assessment statistics showed that increasing the temporal dependence between classification errors did not improve the accuracy of resulting maps of change when the categorical scale of the land-cover classified maps was increased. The increased structural complexity within the time series of maps effectively inhibited the impact of temporal dependence. However, results demonstrated that there are interactions between patterns of error and patterns of change in a post-classification change analysis. These interactions played a major role in determining the accuracy associated with the maps of change.  相似文献   

16.
This paper examines the validity of the public/private and reproductive/productive dichotomies commonly adopted in the analysis of gender and employment. It considers three aspects of the dualisms: spatial division, activity patterns and the construction of identities. The discussion is based on fieldwork undertaken in three districts of Oaxaca City, Mexico, between 1992 and 1995. While recognising the usefulness of spatial dualisms within Mexican cities, the paper seeks to identify the ways in which class and location within the urban space affect the construction of the boundary between “public” and “private”, women's “employment” experiences, and women's identities.  相似文献   

17.
基于居民行为周期特征的城市空间研究   总被引：4，自引：1，他引：3  
钟炜菁  王德 《地理科学进展》2018,37(8):1106-1118
伴随着中国经济社会进入“新常态”的发展阶段,对城市存量空间的研究提出了更加精细化的要求,基于居民行为活动的周期规律对城市空间进行研究,进而提升城市空间的品质日益重要。随着信息通信技术的快速发展,使许多大数据的获取成为可能,并由于其低成本、即时、大样本等优势,在城市空间研究方面具有巨大的价值。以上海市中心城区为例,利用手机信令数据,探究居民活动的空间周期变化特征,并基于空间的周期特征曲线,采用相似性传播聚类算法进行空间分类。研究表明,居民活动有平日一日周期和平日加周末二日周期,与人的作息规律相符合。市核心区、城市副中心及主要就业中心,昼夜波动和平日周末活动强度的差异都较为明显。空间分类结果显示,城市活动空间的组织既体现出个体充分的空间能动性,也反映出对土地使用类型以及设施建设、投入程度的耦合性。上海市内环内核心区混合多样的用地模式使得活动区内居民活动内容丰富,周期特征功能区边界模糊。研究成果可为未来的城市空间规划提供指导,为城市空间结构、功能布置、设施布局等优化提供决策支撑和科学依据。  相似文献   

18.
Impacts on water resources caused by human activity, natural climate variation and long-term climate change are unclear in the US Great Lakes region. Improved understanding of the impact of atmospheric circulation on stream discharge variability into the Lakes is thus important. In this analysis, monthly surface and mid-tropospheric circulation patterns suggest that surface pressure variations over Missouri and Illinois are most strongly correlated to discharge. The mid-tropospheric patterns most directly related to discharge place the Great Lakes in a trough-to-ridge flow pattern. The analysis confirms that at this scale, lee shore advection resulting in ‘lake-effect’ precipitation is not very important to regional discharge, and neither are variations in the Pacific–North American teleconnection.  相似文献   

19.
仝德  周心灿  龚咏喜 《地理科学进展》2021,40(12):2035-2047
共享汽车是城市交通发展的新潮流,论文基于2018年上海市共享汽车运营大数据和城市POI数据,研究共享汽车用户出行的空间、时间和频次特征,并对用户开展出行模式的K均值聚类分析,以期挖掘典型出行规律,为共享汽车运营优化提供依据。研究表明：① 工作日与休息日共享汽车使用行为差异显著,工作日共享汽车出行较集中于中心城区的混合功能区,早晚通勤高峰使用量大;休息日共享汽车出行空间布局较分散,使用量更高、平均单次使用时长更短且仅存在傍晚一个使用高峰。② 上海市共享汽车出行行为可分为工作日通勤的中高频模式,工作日夜间活动的高频模式,工作日偶尔用车晚餐及返家、偶尔用车远距离通勤和夜间长距离返家的低频模式,休息日日间休闲的高频模式、休息日傍晚离家休闲的中长途低频模式、休息日傍晚在休闲地之间穿梭的远距离低频模式、休息日日间加班的低频模式等10种模式。③ 中高频用户主要使用共享汽车实现远距离通勤和周末中长距离休闲活动,空间区域主要集中在中心城区和副中心区域;低频用户使用共享汽车多为夜间、长距离、休息日加班等公共交通难以满足需求、出租车成本过高的情景,空间分布也比较分散。可通过对用户提供差别化用车方案、优化车辆空间调度等方式推进超大城市共享汽车市场发展。  相似文献   

20.
This study aims to characterize urban spatial structure with respect to its multidimensionality. Using an encompassing data set of socioeconomic variables, as well as variables pertaining to the built environment, accessibility and land use, we suggest a quantitatively based urban (sub-) center typology. The fine-grained spatial scale of 1 km2 grid cells permits a higher spatial resolution than that used in most previous studies. Our suggested typology is two-layered: a “macro layer” based on cluster analyses sheds light on urban spatial configurations. A corresponding threshold-based “micro layer” identifies distinctive types of centers and subcenters at the local level. The application of this multi-scale and multivariate typology to four German city regions indicates both the core cities’ morphological dominance and the formation of subcenters with distinct profiles of regional economic importance, land use patterns and urban form. However, a substantial degree of spatial dispersion is observed because much activity is located in non-central locations.  相似文献   

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