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1.
A new generation of greenways has emerged in recent years, the most ambitious of which are nationwide, interconnected networks of multi-use, multi-purpose greenways and trails, clustered under a single national vision. However, because these initiatives have been the focus of so few research studies, opportunities to glean lessons from their planning and implementation have been limited. This paper contributes to addressing this knowledge gap by presenting a comparative account of two networks, the Trans Canada Trail in Canada and Sendero de Chile in Chile. Using document analysis and interviews with officials closely involved in their development, the evolution of both networks is documented over time, emphasizing similarities and differences related to their planning and implementation. Both initiatives have faced significant challenges in reaching their connection goals and have availed themselves of a diverse range of opportunities and strategies to advance their agendas. A simple model of a virtuous cycle is proposed to highlight the positive feedback—between political and public support, sustained funding, partnership development, accessibility for urban residents, and connectivity of the network—generated by sustained network expansion over time. It is hoped that the insights offered from this analysis may offer guidance to inform the development of similar scale projects elsewhere.  相似文献   
2.
Cooling centres provide respite, safety, and social support during extreme heat events for populations that do not have the resources to own or operate in-home air conditioning. The objective of this study was to measure the spatial accessibility of cooling centres and analyze the associations between cooling centre access and marginalization in Montreal, Toronto, and Vancouver, Canada. The potential spatial accessibility of cooling centres within a 15-minute walk was measured at the dissemination area scale using the two-step floating catchment area method. A two-stage modelling approach was used to analyze the associations between cooling centre access and marginalization. Approximately 62%, 58%, and 54% of the populations in Montreal, Toronto, and Vancouver had access to at least one cooling centre. In Montreal and Vancouver, high marginalization areas were more likely to have cooling centre access than low marginalization areas. Of the areas with cooling centre access, smaller access scores were observed in areas with high residential instability. Approximately one-fifth of the areas in each city had no cooling centre access and high marginalization, and may be considered for future cooling centres or programs that improve accessibility to existing centres.  相似文献   
3.
Considering recent formulations of geopolitical culture in combination with concerns that environmental change be included in contemporary geopolitical analysis, this paper examines the implicit geopolitical formulations in recent Canadian federal political discourse both in Stephen Harper's Conservative government and the subsequent Liberal administration. Contrasting earth system science ideas about global transformations with Canadian nationalist rhetoric concerning petroleum production and notions of unlimited resource extraction as parts of national identity sharply highlights the contours of Canadian identity. If sustainability is to be taken seriously, the official nationalist formulation will have to be drastically changed, but as the widespread rejection of the LEAP manifesto suggests, such ideas of a sustainable mode of globalization have yet to substantially influence Canadian political discourse, despite the rhetorical support offered to the Paris Agreement on Climate Change by the Liberal government of Justin Trudeau.  相似文献   
4.
This paper examines the rock art of the nyau secret society of eastern Zambia and central Malai. The art dates principally from the nineteenth and early twentieth centuries. It has been known to researchers since the 1970s but has given up few of its secrets. I examine the questions of why the art was made and why the tradition ceased. Key to answering these is the realization that the art belonged to a specific historical and geographic context: the era and area where nyau was forced to become an underground movement because of its suppression by Ngoni invaders, missions, and the later colonial government. The art provides us with detailed insights into the way nyau has served in the process of overcoming and manipulating the traumatic social changes faced by Chea society in the last few centuries.Cet article examine l'art rupestre de la société secrète de nyau au est du Zambia et Malai centrale. L'art date principalement aux dix-neuvième et bas vingtième siècles. Recherchers ont su l'art depuis les années soixante-dix, mais ils ont appris peu de ses secrets. J'examine les questions de pourquoi l'art était fabriquer et pourquoi la tradition a cessé. Pour résoudre ces questions c'est important à réaliser que l'art était à sa place dans un milieu spécifique d'histoire et géographie: au temps et place où nyau était forcer à devenir un mouvement clandestin à cause de sa répression par les envahisseurs Ngoni, les missions et, plus tard, le gouvernement colonial. L'art nous donne les aperçus détaillé sur comment nyau a servi dans le procès à surmonter et manipuler les changements traumatiques que la société Chea a bravé dans les siècles récents.  相似文献   
5.
师■鼎铭"困伯太师武"一句的"困(韋東)"二字,原文写法非常奇怪。裘锡圭先生释为"東(韋東)",读为"范围",认为是遵循、效法之意。本文同意把后一字释为"(韋東)",但把前一字改释为"困"。"困(韋東)"也是遵循、效法的意思。  相似文献   
6.
Metropolization and the rank/size ’law‘: the Canadian case, 1971–2001 There is currently considerable interest in the process of metropolization. One of the consequences of this process, observed by numerous researchers, is the slower growth and even decline of small and medium cities. From a theoretical point of view, this process is compatible with endogenous growth theory: metropolitan areas offer economic actors certain key factors (access to information, to global networks, etc.) that smaller cities cannot. Concurrently, however, there is a resurgence of interest in Zipf's law and, more generally, in the stability of urban hierarchies. These two bodies of work appear to be in contradiction. However, using Canadian data from 1971 to 2001, we show that whilst metropolization is indeed occurring, this is not necessarily incompatible with a regular urban hierarchy. Indeed, if it is assumed that Zipf's rank‐size rule applies to urban systems in stable socio‐economic contexts, and that this regularity can be disrupted by fundamental social and economic changes, then the current wave of metropolization can be interpreted as a re‐ordering of cities in the face of the major social and economic changes of the 1980s and 1990s, which may eventually lead to a new equilibrium compatible with Zipf's law.  相似文献   
7.
This paper reviews selected evidence of environmental changes in the central Canadian Rockies during the 20th century. The instrumental climate record shows that mean annual temperatures have risen ca. 1.4°C over the last 100 years but seasonal patterns of change are complex. The greatest increases have been in winter temperatures (3.2°C / century). Precipitation data, though limited, show variable patterns of change on decadal scales with generally higher levels of precipitation in the mid-20th century. The longest streamflow record also shows considerable variability, with highest flows in the 1950s. A tree-ring-based temperature reconstruction indicates summer and spring temperatures in the last half of the 20th century are higher than any equivalent period over the last 900 years. Although no accurate regional estimates exist, glaciers have probably lost ca. 25% of their area in the last 100 years and may be smaller now than they have been at any time in the last 3000 years. These two lines of evidence suggest that the climate of the late 20th century is exceptional in the context of the last 1000 to 3000 years. Small but significant vegetation changes are taking place at the upper treeline ecotone in response to climate changes over the 20th century (e.g., seedling establishment). However, the most significant landscape change in the last 100 years is the transformation of the character of the montane forest due to a reduction in forest fire frequency, largely due to an active policy of fire suppression. Dans cet article, on révise certaines manifestations des changements environnementaux qui se sont produits dans les Rocheuses canadiennes au cours du 20ème siècle. Ce registre instrumental climatologique indique que les moyennes annuelles de température ont augmenté d'environ 1,4°C en 100 ans, mais les modèles de changements saisonniers sont complexes. Les plus fortes augmentations ont été notées dans les températures hivernales (3,2°C/siècle). Les données concernant les précipitations - bien que limitées - indiquent des tendances variables de changement selon les décennies et en général des niveaux plus élevés de précipitation au milieu du 20éme siècle. Le plus long enregistrement des débits d'un cours d'eau indique aussi d'importantes variations, les débits les plus forts se situant dans les années 1950. La reconstruction des relevés des températures faite à partir des cernes montre que les températures estivales et printanières de la deuxième moitié du 20ème siècle sont plus élevées qu'elles ne l'étaient durant les périodes correspondantes des 900 dernières annés. Même s'il n'existe aucune donnée règionale exacte, les glaciers ont probablement perdu à peu près 25% de leur superficie au cours du dernier siècle et ils ont atteint leur plus petite taille des 3000 dernières années. Ces deux preuves suggèrent que le climat de la fin du 20ème siècle est exceptionnel dans le contexte des 1000 à 3000 dernières années. Des changements mineurs mais significatifs s'effectuent actuellement dans l'écotone supérieur de la limite des arbres à cause des changements climatiques du 20ème siècle (ex. l'implantation de nouvelles pousses). Pourtant, pendant le dernier siècle, la transformation la plus significative s'est effectuée dans les forêts de montagne. Grâce à une politique active de suppression des incendies de forêt, ceux-ci sont beaucoup moins fréquents.  相似文献   
8.
张爱萍 《清史研究》2020,118(2):1-12
清初,迭遭兵燹的湖南地区经历了兴垦、均编粮里、清丈等重建赋役秩序的过程。其中,衡山县于康熙四十三年实施的"废甲编区"更是呈现出清初里甲赋役改革的丰富面相。因应偏沅巡抚赵申乔革除里排、滚单催征的举措,衡山县打破原有里甲规制的束缚,改革中坚持粮不过区、就地编区的原则,孕育了字区的地缘性色彩,重塑十七字四百三十七区的赋役区划体系。以康熙五十三年新一轮的清丈为契机,知县葛亮臣在业已建立的区划结构内清查荒籍,使字区成为地方重要的赋役征派和土地登记单位。在这一区域变迁的历史过程中,字区的行政区划功能逐渐得到强化和延续,以赋役征派为目的建立起来的基层赋役区划向实体化与政区化迈进,与之相应的行政话语也深刻地影响着民间契约文本的表达。  相似文献   
9.
In Indochina, overseas Chinese were organized by dialect group into associations called congregations, which shared many of the functions of huiguan in China. The spread of overseas Chinese economic and social networks followed a Skinnerian model in which large urban con?régations wielded more political and economic authority than did smaller, rural con?régations. By examining the impacts of French colonialism upon overseas Chinese networks within Indochina and upon overseas connections with their Chinese native places, this paper proposes that the Skinnerian model of local-system hierarchy fits quite comfortably when applied to the world of French colonial Indochina and its overseas Chinese. Furthermore, it argues that French colonialism actually reinforced the Skinnerian hierarchy of politics and markets in ways that endured long after the collapse of Imperial China.  相似文献   
10.
We retrace here spectral presence in the work of Gaston Bachelard which we call «The School of the ETH». We have chosen three fundamental figures: hermann Weyl, Wolfgang Pauli and Gustave Juvet. For the first one, we consider his central and permanent place in the Bachelardian constitution of a philosophy which seeks to be at the height of the new «physical geometry» rigorously constructed in a Riemannian spirit. As for Pauli, we show an unsuspected affinity which is backed up by the remarkable analyses brought to it by philosophy: from the urgent construction of a «quantic metaphysics», founded on the implications of aPauli principle well understood, to the idea of a «metaphysical particle», going on to the decisive and so promising stakes of the «postulate of non-analysis». In the framework of this convergent polyconstruction of the «surrationalist», enterprise, we treat the third figure, less known but equally important, of the mathematician-philosopher Gustave Juvet.  相似文献   
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