全文获取类型
收费全文 | 1979篇 |
免费 | 172篇 |
国内免费 | 146篇 |
专业分类
测绘学 | 49篇 |
大气科学 | 118篇 |
地球物理 | 420篇 |
地质学 | 766篇 |
海洋学 | 408篇 |
天文学 | 20篇 |
综合类 | 57篇 |
自然地理 | 459篇 |
出版年
2024年 | 8篇 |
2023年 | 9篇 |
2022年 | 35篇 |
2021年 | 49篇 |
2020年 | 53篇 |
2019年 | 82篇 |
2018年 | 70篇 |
2017年 | 75篇 |
2016年 | 89篇 |
2015年 | 47篇 |
2014年 | 70篇 |
2013年 | 336篇 |
2012年 | 75篇 |
2011年 | 86篇 |
2010年 | 84篇 |
2009年 | 85篇 |
2008年 | 107篇 |
2007年 | 116篇 |
2006年 | 91篇 |
2005年 | 80篇 |
2004年 | 71篇 |
2003年 | 56篇 |
2002年 | 77篇 |
2001年 | 55篇 |
2000年 | 66篇 |
1999年 | 44篇 |
1998年 | 36篇 |
1997年 | 26篇 |
1996年 | 33篇 |
1995年 | 28篇 |
1994年 | 32篇 |
1993年 | 24篇 |
1992年 | 12篇 |
1991年 | 16篇 |
1990年 | 10篇 |
1989年 | 6篇 |
1988年 | 6篇 |
1987年 | 6篇 |
1986年 | 6篇 |
1985年 | 13篇 |
1984年 | 10篇 |
1983年 | 5篇 |
1982年 | 4篇 |
1981年 | 4篇 |
1980年 | 1篇 |
1979年 | 1篇 |
1978年 | 2篇 |
排序方式: 共有2297条查询结果,搜索用时 15 毫秒
991.
992.
Casey R. Lynch 《Urban geography》2013,34(8):1148-1167
Increasingly over the past few years the building of new cities “from scratch” has become a key strategy to promote development across much of the Global South. While several projects are currently under construction, many others exist primarily as proposals awaiting adequate investment or government action. This paper builds on previous literature that considers representations of such projects – promotional materials, digitally-produced video simulations, and master plans – as key components in the production of imagined urban futures. Through an exploration of the proposed Zone for Economic Development and Employment (ZEDE) in Honduras, this article demonstrates a feminist geopolitical approach focused on how such representations of utopian urbanism circulate through the local communities slated for new city development. I examine how representations of future urban spaces and future urban governance regimes become appropriated by local residents in organizing opposition or otherwise making sense of the proposed project’s potential impact on their lives. 相似文献
993.
Trushna Parekh 《Urban geography》2013,34(2):201-220
In this study, I deploy an ethnographic approach to analyze the detrimental effects of gentrification on longstanding residents in New Orleans’ Tremé neighborhood. I focus on conflicts between long-established residents and gentrifiers over the use of neighborhood space on a day-to-day basis as a means for examining the consequent changes in neighborhood life. As their neighborhood gentrifies, long-term residents of Tremé must contend with greater policing, the erosion of place-based knowledge, practices, and cultural traditions, the loss of social networks, and the closure of vital neighborhood institutions. These changes in neighborhood life provide a starting point from which to begin to understand the broader effects (beyond displacement) that longstanding residents experience as a result of gentrification. 相似文献
994.
《Urban geography》2013,34(7):609-639
This case study applies the segment approach to investigate community sense of place for a small-town tourism business district (TBD). A stratified random sample of residents from Galena, Illinois (population 3,647), is analyzed to identify personal values and behaviors most closely associated with sense of place for downtown. Despite Galena's extreme orientation to tourism, natives and middle-class newcomers generally were found to be equally, and highly, involved with their TBD. Consequently, respondents claimed sentiments of "at-homeness" (or sense of place) for downtown regardless of their duration of residence. However, natives and newcomers collectively valued downtown for different reasons. One implication is that sense of place for downtown can translate into local agency-based projects and interest groups that promote or oppose the transformation of place. In turn, community cohesiveness can be threatened through the process of transforming a historic downtown into a TBD. [Key words: tourism business district (TBD), sense of place, downtown redevelopment, main street, small town.] 相似文献
995.
996.
基于移动平台地震速报短信客户端(EQSMS)的设计与实现 总被引:1,自引:0,他引:1
侯建民 《地震地磁观测与研究》2013,34(3)
通过地震速报短信客户端软件(EQSMS),当用户收到速报短信后即可实时查看速报震中的矢量地理信息、卫星影像信息和震中距等数据,便于应急人员对灾害评估和应急救援等及早做出反应和工作部署. 相似文献
997.
Kai Cao Michael Batty Bo Huang Yan Liu Le Yu Jiongfeng Chen 《International journal of geographical information science》2013,27(12):1949-1969
A spatial multi-objective land use optimization model defined by the acronym ‘NSGA-II-MOLU’ or the ‘non-dominated sorting genetic algorithm-II for multi-objective optimization of land use’ is proposed for searching for optimal land use scenarios which embrace multiple objectives and constraints extracted from the requirements of users, as well as providing support to the land use planning process. In this application, we took the MOLU model which was initially developed to integrate multiple objectives and coupled this with a revised version of the genetic algorithm NSGA-II which is based on specific crossover and mutation operators. The resulting NSGA-II-MOLU model is able to offer the possibility of efficiently searching over tens of thousands of solutions for trade-off sets which define non-dominated plans on the classical Pareto frontier. In this application, we chose the example of Tongzhou New Town, China, to demonstrate how the model could be employed to meet three conflicting objectives based on minimizing conversion costs, maximizing accessibility, and maximizing compatibilities between land uses. Our case study clearly shows the ability of the model to generate diversified land use planning scenarios which form the core of a land use planning support system. It also demonstrates the potential of the model to consider more complicated spatial objectives and variables with open-ended characteristics. The breakthroughs in spatial optimization that this model provides lead directly to other properties of the process in which further efficiencies in the process of optimization, more vivid visualizations, and more interactive planning support are possible. These form directions for future research. 相似文献
998.
《Urban geography》2013,34(2):169-174
This commentary critically engages with arguments made by Loïc Wacquant in his book Urban Outcasts on the nature of public discourse regarding concentrated urban poverty in the United States. In particular, it elaborates a critical reading of the international circulation of social-scientific analyses of urban poverty—in particular the concept of the "urban underclass"—which rose to prominence through research on Chicago neighborhoods. This concept has subsequently influenced scholarly and public policy approaches to characterizing and combating entrenched urban poverty and long-term unemployment in Europe, Asia, and elsewhere. I challenge the appropriateness of the concept as well as the direction of public policymaking that has downplayed, if not ignored, questions of job availability and job quality in urban areas. 相似文献
999.
《Urban geography》2013,34(8):647-671
Centrality within a city and neighborhood characteristics have often been used as indicators of access to employment and services in statements about urban form and accessibility, but there are reasons to question the appropriateness of doing so. This paper evaluates the importance of geographic context within the urban environment (both location within cities as well as neighborhoods characteristics) for individuals in Portland, Oregon. Because conventional accessibility measures cannot incorporate individual characteristics, space-time individual accessibility measures were used with multilevel modeling to isolate the effects of individual level variations from that of geographical context. The results show that the influence of context on individual accessibility is weak, as accessibility tends to reflect individual and household characteristics rather than the local urban environment. Accessibility cannot be determined from location within cities, or from land uses around an individual's home, implying that the use of urban design to influence accessibility is inappropriate. 相似文献
1000.
Shrinking New Orleans: Post-Katrina Population Adjustments 总被引:1,自引:0,他引:1
《Urban geography》2013,34(5):675-699
The flooding caused by hurricane Katrina in 2005 acted as a catalyst for an abrupt change of the demographic landscape of the New Orleans metropolitan area. New Orleans city proper has been a shrinking city for the last half century, but its population loss was balanced by expanding suburbs until 2005. Based on a comparison of the newly released 2010 census data with the 2000 data, this paper discusses the major population adjustments that have resulted from the disaster. Hurricane Katrina has caused the entire metropolitan area to shrink much faster than previous declines. Five years after the storm, New Orleans displays some limited signs of resilience, although the storm seems to have accelerated its population decline. Furthermore, a close examination of the available data shows us that Katrina has provoked a major change in the city's ethnic landscape. 相似文献