全文获取类型
收费全文 | 2013篇 |
免费 | 112篇 |
国内免费 | 22篇 |
专业分类
财政金融 | 78篇 |
工业经济 | 84篇 |
计划管理 | 631篇 |
经济学 | 289篇 |
综合类 | 138篇 |
运输经济 | 418篇 |
旅游经济 | 45篇 |
贸易经济 | 178篇 |
农业经济 | 82篇 |
经济概况 | 204篇 |
出版年
2024年 | 4篇 |
2023年 | 39篇 |
2022年 | 47篇 |
2021年 | 61篇 |
2020年 | 63篇 |
2019年 | 77篇 |
2018年 | 61篇 |
2017年 | 80篇 |
2016年 | 83篇 |
2015年 | 78篇 |
2014年 | 156篇 |
2013年 | 164篇 |
2012年 | 161篇 |
2011年 | 201篇 |
2010年 | 135篇 |
2009年 | 123篇 |
2008年 | 146篇 |
2007年 | 84篇 |
2006年 | 92篇 |
2005年 | 72篇 |
2004年 | 71篇 |
2003年 | 52篇 |
2002年 | 15篇 |
2001年 | 11篇 |
2000年 | 16篇 |
1999年 | 10篇 |
1998年 | 9篇 |
1997年 | 10篇 |
1996年 | 5篇 |
1995年 | 4篇 |
1992年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1985年 | 2篇 |
1984年 | 4篇 |
1982年 | 6篇 |
1979年 | 2篇 |
排序方式: 共有2147条查询结果,搜索用时 15 毫秒
1.
Innovation clusters combining public and private effort to develop breakthrough technologies promise greater technological advances to slow down climate change. We use a multi-country model with an emission trading system to examine whether and how international climate policy can incentivize countries to create such innovation clusters. We find that a minimal carbon price is needed to attract applied research firms, but countries may nevertheless fail to invest in complementary research infrastructure. We construct a mechanism that leads to innovation clusters when emissions targets are set before uncertainty surrounding technological developments is resolved. It is a combination of low permit endowments for the country with the lowest costs to build the needed infrastructure, compensation for this country by profits from permit trade, and maximal possible permit endowments for the remaining countries. We outline how the EU-ETS can be further refined according to this mechanism. 相似文献
2.
新基建作为现代化基础设施体系的重要组成部分,已经成为中国经济高质量发展的重要支撑。基于2015—2021年中国71个城市的面板数据,构建双向固定效应、中介效应和调节效应三种回归模型,实证检验新基建发展对城市产业结构水平的影响及内在机制。研究发现:新基建发展能促进产业高级化水平,改善不合理的产业结构状态,提升产业合理化水平;新基建通过发展物联网和激励城市研发创新两种间接路径对产业结构转型升级产生积极影响;新基建对产业结构水平的影响受到地方政府干预行为的调节作用,在地方政府合理的行政管理下,新基建对产业转型升级的积极作用更为明显;新基建发展对产业结构水平的提升作用具有区域异质性和城市规模异质性,在中西部地区和大城市地区的作用效果更为明显。 相似文献
3.
优化城市基础设施对于提升居民消费水平具有积极意义。交通与通讯两类基础设施对居民线上、线下消费的影响存在差异。在普及网购的同时改善城市居民出行条件,使实体店在展示产品、现场体验等方面与电商形成互补,将有助于实现线上、线下渠道的积极互动。以2011—2016年全国近300个地级市构建的面板数据进行计量分析,验证了基础设施对居民消费的促进作用,并发现当前交通、通讯两类设施的交互作用主要体现为协同效应。进一步的研究表明,以完善基础设施支持线上、线下渠道共同发展,还能够适应居民家庭年龄结构变化的新特点。上述结论说明,以完善基础设施促成渠道协同,将对全面优化消费者体验、提升居民消费水平产生重要作用。 相似文献
4.
以甘肃省9个县市的调查数据为基础,将社会资本划分为社会参与、社会规范、互惠网络三个维度,运用结构方程模型,来探讨三个维度对农村基础设施管护效果的影响。结果表明:(1)社会规范对农村基础设施管护效果显正向影响。(2)互惠网络对农村基础设施管护效果显负向影响。(3)社会参与对农村基础设施管护效果的直接影响不显著,但通过社会规范及互惠网络间接产生影响。(4)就总效应而言,社会规范对农村基础设施管护效果的影响要大于社会参与及互惠网络产生的影响。 相似文献
5.
This study demonstrates the value of integrating different analytical perspectives to identify significant factors and characterize their importance. Specifically, we combine three analytical methods – partial least squares structural equation modeling (PLS-SEM), necessary condition analysis (NCA), and fuzzy set qualitative comparative analysis (fsQCA) – to create an expanded analytical process that enables informed decision-making. PLS-SEM identifies significant correlations between the predictor and outcome variables, NCA identifies critical bottlenecks required for a specific outcome, and fsQCA identifies configurations of conditions sufficient for producing a specific outcome. By applying this expanded analytical process to subjectively reported data on service quality and perceived accessibility, collected from five Nordic cities, we gain new insights into attracting an aging population to public transport. This study contributes to a better understanding of the nuances in the data, which is valuable for both research and practice. 相似文献
6.
We examined 2007, 2010, 2012, 2014, and 2016 data from 49 countries to determine changes wrought by China’s Belt and Road initiative; we also used panel data regarding the Maritime Silk and Inland Silk Roads to test initiative effects on Chinese exports. Post-initiative infrastructure expansion and logistics performance improvements led to positive effects on China’s exports. Additionally, legal-system similarities and inland borders with trade partners had a more positive effect on Chinese exports in the Inland Silk Road, while population and free trade agreements were found to have a more positive effect on the Maritime Silk Road. 相似文献
7.
William Herbert Lee Stafford George Adrian Lotter Graham Paul von Maltitz Alan Colin Brent 《Development Southern Africa》2019,36(2):155-174
ABSTRACTThe benefits of biofuels depend on the feedstock, conversion pathway and local context. This paper assesses biofuels technology readiness and developments to provide foresight to biofuels development in Southern Africa. Efficient conversion pathways, coupled with biomass from waste or high-yielding energy crops, will reduce both the costs of biofuels production, and the environmental impacts. Compared to petroleum fuels, the current commercial biofuels (ethanol, biogas and biodiesel) typically offer carbon emission reductions of 30–50% but are marginally more expensive. The extent of biofuels market penetration will therefore be influenced by mandates (blending targets) and subsidies (green premium). Advanced biofuels promise greater efficiencies and carbon emission reductions at reduced cost but will require further research and development to reach commercialisation. If developed appropriately, biofuels can reduce carbon emissions and improve energy security, while enabling sustainable agriculture and improved natural resources management. 相似文献
8.
在经济新常态下积极推动发展高端乡村旅游产业已经成为我国建设美丽乡村的重要着力点,与此同时"反生态"问题的不断显现已成为阻碍我国乡村旅游经济实现可持续发展的掣肘,因此,高端乡村旅游产业的发展模式向生态化转型势在必行。以天津市蓟州区乡村旅游景区的环保基础设施为研究对象,从环境情况、设施配备和从业人员3个方面确定了20个影响因素,通过向游客发放问卷进行满意度调查,从游客感知角度的基础上采用IPA模型分析游客对景区环保基础设施的重要性和满意度。结果表明,准则层及指标层感知均值都为游后感知实绩(满意度)<游前期望(重要性),在此基础上提出用冲突协同理论来指导蓟州区高端乡村旅游产业发展中的环境管理工作,实现高端乡村旅游产业与环保基础设施的协同发展,也能为今后的相关研究奠定基础。 相似文献
9.
Transport infrastructure is an important subsector within infrastructure, but knowledge of its equities in terms of risk-return characteristics and contribution to portfolio performance is still limited. This study assesses the subsector individually and in a multi-asset, index-based portfolio. In doing so, we apply a t-Copula-based Conditional Value-at-Risk model to simulate risk and returns. Our findings reveal that the subsector has a relatively low dependency on other equities, performs like other alternative asset classes such as general real estate, and does not grant significant risk diversification benefits for mainstream institutional investors such as pension funds. Investors aiming for higher target returns may however assign substantial weights to transport infrastructure, supporting our conjecture that it does not share the same asset class characteristics as general infrastructure. By contrasting Value-at-Risk (VaR) and Conditional Value-at-Risk (CVaR) scores for both the mean-variance framework and the t-Copula simulation, we further document the limitations of traditional VaR approaches. Hence, this study’s results support the use of risk assessment tools that incorporate non-normal distributions to represent multivariate dependence structures. 相似文献
10.
Lisa Björkman 《International journal of urban and regional research》2018,42(2):276-294
Two decades ago, the rules governing the provision of piped municipal water supply in Mumbai became linked to the policy frameworks governing eligibility for a property titling scheme. This article outlines the ideological basis and practical implications of the shift, as well as the contradictions of the new regulatory regime. The article demonstrates how these contradictions have been mediated by the material and practical knowledge, embodied expertise, local authority and wide‐ranging socio‐political work of two sets of actors: municipal water engineers and a cast of characters known locally as ‘plumbers’. The social, political and hydraulic imaginaries animating the work of ‘plumbing’ are bound up with a temporal and spatial imaginary distinctly at odds with the network‐flow conception of hydraulic engineering within which the work of water supply planning and distribution in Mumbai is conceptualized, materialized and institutionalized. The hydraulic and legal contradictions of these clashing infrastructural idioms––of flow and event––have rendered the regulatory framework highly unstable. These contradictions eventually erupted in Mumbai's waterscape, leaving the city's water infrastructures suspended in a highly politicized state of limbo between dueling infrastructural imaginaries. 相似文献