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51.
52.
City governments are embracing data-driven and algorithmic planning to tackle urban problems. Data-driven analytics have an unprecedented capacity to call urban futures into being. At the same time, they can depoliticize planning decisions. I argue that this shift calls urban studies scholars to investigate geographies of algorithmic violence—a repetitive and standardized form of violence that contributes to the racialization of space and spatialization of poverty. This article examines this broader phenomenon through the case of a proprietary market value assessment that is being used to guide development in cities across the United States. The assessment employs an algorithm that helps city officials make critical decisions about which neighborhoods to target for investment, disinvestment and public service upgrades or disconnections. I argue that the racial, infrastructural, and epistemological violence associated with this evaluation can potentially lead to a new kind of municipal redlining. The article brings insights from critical race theory into conversation with critical scholarship on algorithms by analyzing how algorithmic violence works through data-driven planning technologies to depoliticize and leverage power while further entrenching racism and inequality.  相似文献   
53.
Unsanctioned tent cities are increasing in number in cities throughout the western United States. Scholars explain the phenomenon as homeless people asserting their ‘right to the city’ or as ‘managed marginality’. These explanations capture much of the socio-political relationship between local government and homeless populations, but do not explain the long-term persistence of tent cities and the fluctuating nature of their visibility. A spatial history of informal encampments in Sacramento at three key moments—the founding of the city, the Great Depression and the Great Recession—reveals a long-term ebb and flow of tent cities occupying close-to-the-center, urban vacancies. Urban vacancies arise from the partitioning of the city into specific purposes, places and people, a taken-for-granted perception of how cities should be. The visibility of tent cities disrupts this aesthetic notion of stability and growth as homeless people use the tent to protest their isolation and exclusion.  相似文献   
54.
This article examines the processes of urban commoning and its co-produced features of urbanity, making the claim that, through these processes, informality becomes translated into institutionalized city planning. Commoning is analysed through a comparative study that utilizes contingent features of urbanity and three modalities accommodating the informality–formality meshwork during urban change. The article contributes to research on urban transformations by integrating commons, informality dynamics and the constitution of state institutions. This focus is elaborated with reference to collective gardening practices in the context of two of the less studied European cities, Narva in Estonia and Tampere in Finland. The results of the study indicate that urban commoning takes place through delegating a public mandate and enacting uncertainty, two processes that informalize city government practices. Particular differences appeared in regard to the institutional porosity that enables unregulated spaces of collective gardening to be mobilized as part of urban politics. We argue that networked movements appear as an essential part of the urban logic of action producing meaningful connections in an informal–formal meshwork and bringing together multiple sites in the commoning process.  相似文献   
55.
Welfare-state transformation and entrepreneurial urban politics in Western welfare states since the late 1970s have yielded converging trends in the transformation of the dominant Fordist paradigm of social housing in terms of its societal function and institutional and spatial form. In this article I draw from a comparative case study on two cities in Germany to show that the resulting new paradigm is simultaneously shaped by the idiosyncrasies of the country's national housing regime and local housing policies. While German governments have successively limited the societal function of social housing as a legitimate instrument only for addressing exceptional housing crises, local policies on providing and organizing social housing within this framework display significant variation. However, planning and design principles dominating the spatial forms of social housing have been congruent. They may be interpreted as both an expression of the marginalization of social housing within the restructured welfare housing regime and a tool of its implementation according to the logics of entrepreneurial urban politics.  相似文献   
56.
本文利用2003—2016年中国278个城市的面板数据,基于地方政府竞争视角,探讨财政分权对城市创新水平的影响。结果表明:财政分权显著抑制城市创新水平的提升,且经过一系列稳健性检验后该结论依然成立;财政分权对城市创新水平的影响具有异质性,如在科教水平较低、级别较低及中小城市,财政分权显著抑制城市创新,而在科教水平较高、级别较高及大城市却并未抑制城市创新;财政分权通过促进地方政府“为增长而竞争”“为引资而竞争”、抑制地方政府“为创新而竞争”等途径对城市创新水平产生负向影响。研究结论为从政府财政体制改革视角促进城市创新提供启示。  相似文献   
57.
从大气环境与城市竞争力的关联性入手,将大气环境风险、现状和治理纳入评价指标体系,基于组合权重的大气环境竞争力评价模型,对2013-2017年京津冀13个城市的大气环境竞争力水平进行了测评,并结合空间自相关分析和障碍度模型揭示了其空间效应及障碍因素。结果显示:京津冀城市大气环境竞争力存在明显的空间差异,呈"北部高、南部低、局部跳跃"格局,城市差距逐渐缩小;京津冀城市大气环境竞争力呈显著的空间集聚效应且存在正向相关性,空间分布格局相对稳定。  相似文献   
58.
为解决位置指纹定位在离线阶段构建位置指纹库时耗费的人力和时间成本较大,构建指纹库效率低和利用空间插值法构建的指纹库精度不高的问题,提出了一种融合反距离加权和矩阵填充的位置指纹库构建算法。该算法仅需人工采集定位区域内少量参考点的接收信号强度值用作信标点指纹信息,结合反距离加权算法特性计算出次信标点指纹信息,根据位置指纹库数据矩阵的低秩性,应用奇异值阈值矩阵填充算法构建出位置指纹数据库。仿真实验结果表明,所提算法有效降低了矩阵填充算法构建位置指纹库所需的人工和时间成本,构建出的位置指纹库定位性能优于反距离加权和克里金空间插值法,接近传统人工采集法,显著地提高了位置指纹库的构建效率。  相似文献   
59.
随着空中交通的信息传输与新应用拓展需求不断增加,1090ES信号容量有限问题日益显现,对1090ES信号进行容量扩充是一种有效解决途径。针对一种基于脉内调相的1090ES信号扩容技术,给出了叠加调制的信号模型,研究了1090ES信号的解调解码算法;在GNU Radio+ USRP软件无线电平台上,实现了1090ES扩容信号的产生和接收处理,包括脉冲位置调制(Pulse Position Modulation,PPM)与8PSK叠加调制、低通滤波、报头检测、载波同步、PPM解码和相位解调等,并利用Matlab对实验的解码错误率和信号的频谱特性做了统计分析与仿真,结果表明了该扩容技术的可行性。  相似文献   
60.
随着中国经济的快速发展,能源消费也快速增长。随着节能减排的压力越来越大,能源的代谢需要根据需求进行更替。论文就京津冀城市群能源代谢时空特征分析并对能量代谢进行优化和调控提出建议。  相似文献   
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