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1.
Mijatovi? and Pistorius proposed an efficient Markov chain approximation method for pricing European and barrier options in general one‐dimensional Markovian models. However, sharp convergence rates of this method for realistic financial payoffs, which are nonsmooth, are rarely available. In this paper, we solve this problem for general one‐dimensional diffusion models, which play a fundamental role in financial applications. For such models, the Markov chain approximation method is equivalent to the method of lines using the central difference. Our analysis is based on the spectral representation of the exact solution and the approximate solution. By establishing the convergence rate for the eigenvalues and the eigenfunctions, we obtain sharp convergence rates for the transition density and the price of options with nonsmooth payoffs. In particular, we show that for call‐/put‐type payoffs, convergence is second order, while for digital‐type payoffs, convergence is generally only first order. Furthermore, we provide theoretical justification for two well‐known smoothing techniques that can restore second‐order convergence for digital‐type payoffs and explain oscillations observed in the convergence for options with nonsmooth payoffs. As an extension, we also establish sharp convergence rates for European options for a rich class of Markovian jump models constructed from diffusions via subordination. The theoretical estimates are confirmed using numerical examples.  相似文献   
2.
针对双站定位涉及的跳频信号多普勒频差估计问题,提出了归一化的频差最大似然估计算法,利用两个定位站接收到的跳频脉冲串信号,构建一个关于基准跳频频率多普勒频差的似然函数,通过网格搜索得到使似然函数最大的多普勒频差估计,既解决了跳频信号在不同跳频频率上多普勒频差不一致的问题,又充分利用在不同频率的脉冲串信号提高了多普勒频差估计精度。通过仿真对算法的性能进行了评估,结果表明,与基于子空间的算法比较,在脉冲数达到240个时,所提算法执行效率提升30%以上。  相似文献   
3.
Recent empirical assessments revealed that footprint indicators calculated with various multi-regional input–output (MRIO) databases deliver deviating results. In this paper, we propose a new method, called structural production layer decomposition (SPLD), which complements existing structural decomposition approaches. SPLD enables differentiating between effects stemming from specific parts in the technology matrix, e.g. trade blocks vs. domestic blocks, while still allowing to link the various effects to the total region footprint. Using the carbon footprint of the EU-28 in 2011 as an example, we analyse the differences between EXIOBASE, Eora, GTAP and WIOD. Identical environmental data are used across all MRIO databases. In all model comparisons, variations in domestic blocks have a more significant impact on the carbon footprint than variations in trade blocks. The results provide a wealth of information for MRIO developers and are relevant for policy makers designing climate policy measures targeted to specific stages along product supply chains.  相似文献   
4.
多径效应导致基于信号接收强度(RSSI)的室内定位方法精度不高,采用更细粒度的物理层信道状态信息(CSI)可以区分不同路径,提高定位精度。在已有基于CSI室内定位方法的基础上,通过改进对数距离路径损耗模型,得到CSI与传输距离的关系,并结合目标位置所测得的CSI值回归出目标与发射端的距离,最后通过三边定位法预测出目标的位置坐标。实验表明,相比基于RSSI的定位方法以及已有的基于CSI的定位方法,所提方法2 m以内的误差概率提高了将近40%和20%,有效提高了定位精度。  相似文献   
5.
何寿奎 《企业经济》2020,(1):5-11,F0002
本文以交通运输业高质量发展与环境保护融合为导向,分析交通运输业高质量发展与环境保护现状,阐述交通运输业高质量发展与环境保护融合的内在机理,剖析交通运输高质量发展与环境保护融合的政策驱动、绿色发展需求驱动、优质服务动力、转变发展动力、技术创新动力、利益补偿动力等外部融合动力机制,以及行业竞争力动力、基于绿色发展的组织管理制度创新、绩效驱动等内部融合动力机制。研究建议提出:构建低碳交通技术标准体系,健全基于环境保护的交通建设运营治理机制;探索低碳交通与环境保护成本补偿制度,优化交通运输业产业结构,推动交通运输行业技术升级;建立公路建设与运营环境风险智能控制机制,应用智能技术对交通运输业环境进行协同治理。  相似文献   
6.
董恺  岳书铭 《科技和产业》2019,19(9):134-138
由于基层政府长期存在财力事权上的不均衡,我国基层地区义务教育供给存在着差距。2001年的"以县为主"的县统筹财政制度开始实行,义务教育的负责主体变成了县级政府。借助2002年到2016年的山东省县级数据,运用泰尔指数作为分析工具,结合此期间山东省出台的教育改革措施,分析其对于缩小义务教育差异的影响。研究发现,政策制度仅仅改善了中等收入县级地区之间的差距,对于高收入和低收入地区并没有太好的效果,就目标而言,由于县级各地区上经济实力和义务教育规模的固有差距,导致无法取得理想中的效果。  相似文献   
7.
We identify farms’ optimal investment path in capital assets and compare it with their actual investment to assess the direction and extent of deviation from the optimal investment. A probit model is further used to investigate the determinants of the probability that a farmer over‐ or under‐invests in capital assets. We use a panel dataset of Dutch dairy farms over the period 2003–2013, and find that most farms under‐invest in capital assets during the study period. Although the number of farms that had over‐invested in capital assets is relatively small, these farms account for the biggest share of total investment in capital assets. The probit results show that liquidity, agricultural support payments, age, land tenure and standard output size are important variables explaining the likelihood of over‐and under‐investment.  相似文献   
8.
Based on the wavelet analysis approach, this paper firstly examines the dynamic relationship between global economic activity (proxied by the Kilian economic index) and crude oil prices in both time- and frequency-domains. Our empirical results demonstrate significant correlation between crude oil prices and global economic activity at high frequencies (in the short run) during the entire sample period; however, the co-movement between the two at low frequencies (in the long run) is weaker and exists only during certain proportions of the sample period. We also document evidence that global economic activity and oil price are positively correlated, with dynamic lead-lag relationships across time. Our findings are robust to alternative choices of oil price indexes and controlling for other confounding factors such as geopolitical risk, armed conflicts, economic policy uncertainty and equity market uncertainty. The current study provides valuable implications for oil market investors based on the information of global economic situation and its dynamic relationships with oil prices.  相似文献   
9.
Poor bank governance has disastrous consequences for economies as the 2007–2009 financial crisis has shown. In the aftermath, board diversity is identified as an effective mechanism to enhance bank governance. Diversity, creating cognitive conflict between board members, is expected to enhance board's independence of thought to better perform monitoring and advising functions. Age is a key demographic measure and age dissimilarity between the chair and the CEO in non-financial firms leads to better economic outcomes (Goergen, Limbach, & Scholz, 2015). In this paper, we examine whether chair-CEO age dissimilarity can mitigate banks' excessive risk-taking behaviour. Using a unique sample of 100 listed banks in Europe between 2005 and 2014, we find that age difference between the chair and the CEO reduces bank risk-taking. A chair-CEO generational gap –defined as a minimum of 20 years' age difference– has a larger impact in reducing risk-taking.  相似文献   
10.
Internationally, academic hospitals are giving increasing attention to diversity management. This paper sheds light on the actual praxis of cultural diversity management by professionals in workplace interactions. An ethnographic study in a Dutch academic hospital showed that normalization practices were obscuring diversity issues and obstructing inclusion of cultural minority professionals. The normalization of professionalism-as-neutral and equality-as-sameness informed the unequal distribution of privilege and disadvantage among professionals and left no room to question this distribution. Majority and minority professionals disciplined themselves and each other in (re)producing an ideal worker norm, essentialized difference and sameness, and explained away the structural hierarchy involved. To create space for cultural diversity in healthcare organizations in the Netherlands and beyond, we need to challenge normalization practices.  相似文献   
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