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1.
公共交通是我国老年人出行的主要交通方式之一,公交移动性是衡量老年人生活质量和幸福感的重要指标。从季节和空间双重维度分析老年人公交移动性的影响因素有助于深入理解老年人出行行为机制。利用公交刷卡数据和地理探测器方法分析了季节时空因子对老年人公交移动性的影响。研究发现:①不同季节中空间因子对老年人移动频率、移动半径和移动熵的解释力和显著性存在明显差异,对老年人移动性影响机制的分析应考虑时空变化的双重影响;②不同空间因子之间以及季节与空间因子之间的交互作用可以显著增强对老年人移动性空间分异的解释力,考虑多个因素的协同效应对深入理解老年人行为有一定帮助。研究试图拓宽老年人移动性影响因素的分析思路,为老年宜居城市建设和城市移动性规划提供重要支撑。  相似文献   
2.
Whilst the advantages of the application of Land Readjustment (LR) are well known, there are nevertheless numerous countries in which application of LR is difficult or has not been successful. In its analysis of land readjustment constraints, conditions and the international practice, this paper contributes to improving the implementation of an LR system, particularly with respect to the management process. At the international level, management models in seven countries were studied: Australia, France, Germany, Japan, South Korea, Spain and Sweden. In Portugal, three case studies in the municipalities of Almada, Coimbra and Lisbon were selected, with semi-structured interviews being conducted with the respective managing entities. The management models are distinguished by the type of initiative and leadership processes, relations among stakeholders, managing entities and operating rules. It can be concluded that the role of the public authority as the process facilitator from the very initial stages, the existence of a managing entity and a board of specialists, and the legal conditions governing expropriation are key factors for the improvement of land readjustment management.  相似文献   
3.
手机信令数据所代表的人流联系与国内外研究常用的企业关联数据在测度城市关联存在何种差异,尚缺乏明确的研究。本文以江西省北部地区为研究对象,分别以手机信令数据、企业关联数据测度城市关联,比较了两种城市关联与城市之间空间距离、人口规模的关系,比较了两种城市关联网络的层级、结构、腹地。主要研究发现:人流联系不仅集中在城市周边地区,而且集中于较高等级城市之间;经济联系则主要集中在较高等级城市之间。人流联系、经济联系受到城市人口规模影响均较小。人流联系显著地符合幂函数空间衰减规律。手机信令数据和企业关联数据是两种不同的城市关联数据,但可互为补充,较为全面地反映城市关联。  相似文献   
4.
Historical towers, in particular medieval towers, are an important part of cultural heritage, and their preservation mandates monitoring and detailed analyses of vulnerability under seismic actions as well as of their long-term performance. Certain aspects of structural nature are linked to the masonry behavior as a unilateral material, and other are aspects related to the interaction with soft soil conditions. This study aims to contribute to the aspects of preservation by exploring the role of the soil-structure interaction in predicting the behavior of the structures, with specific reference to the well-documented case history of the medieval Ghirlandina Tower (Modena, Italy). A significant contribution comes from an experimental identification analysis, performed in the presence of ambient vibration. A novel finding is that the soil structure interaction cannot be neglected, in contrast to most published identification analyses that usually assume the structure to have rigid constraint at base.  相似文献   
5.
In the fourth millennium BP, there were major environmental and cultural changes on the Andean altiplano of South America, but the chronology remains vague. A recent synthesis describes a slow, gradual transition from hunting and gathering to agropastoralism. This proposal is tested by refining the date of the onset of more humid and stable conditions, around 3550 cal BP, based on a Bayesian model of 26 dates from Lake Wiñaymarka and an updated calculation of the lacustrine offset. This is compared to Bayesian models of 191 dates from 20 archaeological sites, which incorporate a number of recently processed radiocarbon dates. A synthesis is presented of 15 full coverage surveys, a summed probability distribution, and a Bayesian model of the transition to ceramics, which together support a scenario of a very rapid demographic increase. Fourteen models from archaeological sites are cross-referenced in a composite model, which identifies a brief, altiplano-wide emergence of agropastoralism with starting and ending boundaries of 3540 and 3120 cal BP, respectively. This starting boundary correlates strongly with the onset of improving environmental conditions, indicating synchronous cultural and environmental change. The suite of accelerating cultural changes included a marked reduction in mobility, a demographic surge, increased subsistence diversity, the adoption of ceramics, farming and the integration of camelid herding into a remarkably resilient economic strategy still in use today. This is a highly relevant but yet to be used comparative case study for the variable tempos of ‘big histories’, and ecocultural interactions that generate rapid, emergent episodes of wide-spread and enduring cultural change.  相似文献   
6.
This paper aims to trigger discourse about the emergence of a new type of social scientific model — Exploratory Models — which draw on Big Data, computer modeling and interdisciplinary research to tackle complex social scientific processes. First, we define Exploratory Models referring to Batty and Morgan and Morrison. We then present changes to the traditional modeling paradigm. We show how Exploratory Models circumvent challenges related to the idiosyncracy, self-reflexivity and acceleration of social phenomena, which limit predictive effectiveness of traditional models. We show that Exploratory Models are better equipped to tackle complex problems due to their capacity to process heterogeneous datasets. Having established that Exploratory Models are predominantly problem- and data-driven, we emphasize that scientific theory is indispensable to their progress. Finally, the development of an integrative platform is suggested as a way of maximizing the benefits of this approach. Discussion concludes by flagging areas for further research.  相似文献   
7.
This paper argues that the role of the planning system in the overproduction of development during Ireland’s Celtic Tiger needs to be analysed as instructive of contemporary neo-liberal transformations of strategic spatial planning. Leaning on a Foucauldian governmentality perspective, the genealogy of modern Irish planning practice is explored to elucidate how neo-liberal rationalities became embedded in institutional norms through consensus-driven partnership governance. The central premise is that the turn to ‘strategic spatial planning’, particularly with the publication of the National Spatial Strategy in 2002, was usefully exploited to mask the spatial politics of the ever-increasing need for the state to facilitate capital switching into built environment formation in order to maintain conditions of high economic growth. Using the empirical case study of housing development in the ‘Upper Shannon’ region and large-scale commercial development in County Meath, it is argued that this contributed to a destabilization of the planning system and an abandonment of basic planning principles. The paper concludes that, in the context of the new and deeply uneven economic geography of post-crisis Ireland, there is an urgent need for a repoliticized critique of normative interpretations of strategic spatial planning practice in order for more progressive practices to emerge.  相似文献   
8.
This paper evaluates chronological trends in the presence and absence of domestic animal bone (sheep, goat, and cattle) and pottery in Namaqualand, the proposed gateway to the rest of South Africa for early herders or hunter-gatherers with sheep and ceramics. We update date calibrations with local ΔR corrections and mixtures of recent calibration curves and include five previously unpublished dates. We use histograms of calibrated medians, sorted in 100-year bins, to assess sustained regional patterns with dates associated with domestic animal bone and pottery (n = 73). While too small to be useful as a population proxy, the current set of dates does reveal three pulses of occupation separated by two clear gaps, which we evaluate with a Bayesian model of three sequential phases. The model's boundaries are used as estimates of the dates of Early (AD 80–210), Middle (AD 490–790), and Late (AD 1180–1690) occupational phases separated by two substantial lapses of 280 and 380 years, respectively. The alternating phases of presence and absence are suggestively correlated with climate shifts, leading to a discussion of the idea that effective moisture was a crucial factor in choosing whether to occupy Namaqualand. The set of archaeological dates has greater temporal and spatial resolution than many regional climate data, so we suggest that these trends may more accurately reflect the variable conditions specific to Namaqualand, at least until they are refined by future climate research.  相似文献   
9.
Ancient human migrations provide the critical genetic background to historical and contemporary human demographic patterns. However, our ability to infer past human migration events, especially those that occurred over rapid timescales, is often limited. A key example is the peopling of Polynesia, where the timing is relatively well defined, but the exact routes taken during the final stages and the source populations are not. Here, we discuss the technical limitations of current methods for inferring rapid human migration events, using the final stages of Polynesian migration as an example. We also introduce a promising new proxy method to infer human migrations—patterns of bacterial evolution within ancient dental calculus (calcified plaque). While we focus on Polynesia, this method should be applicable to other past migrations, enhancing our understanding of human prehistory and revealing the crucial events that shaped it.  相似文献   
10.
江西省区域经济发展空间差异研究   总被引:20,自引:0,他引:20  
俞勇军  陆玉麒 《人文地理》2004,19(3):41-45,30
区域差异历来是政府关注的重要问题,也是区域发展理论研究的主要课题。江西省受周边强经济中心的影响,经济区位边缘化趋势明显。近年来江西省突破原来农业大省的发展思路,致力引进发达地区和国外的技术和资金,工业化水平明显提高。目前江西省内部地区差异较1990年明显扩大,而且表现出各地区相对波动较大的特征。本文采用偏离一份额模型,对江西1990-2001年间11年来的发展状况分两个阶段进行分析,探讨江西省区域经济发展差异的空间结构特征,将江西划分为4种发展类型。江西省各地区区位条件的变化是其经济发展空间差异的驱动因素。  相似文献   
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