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71.
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73.
The development of an effective spatial data infrastructure (SDI) often occurs in a fragmented organizational environment requiring a high level of inter-organizational collaboration. Different organizations from various jurisdictions need to work together closely when agreeing on how they will jointly register, store, use and share data and how they will make their data available to the wider society. However, this collaboration is generally regarded as very difficult. For example people often resist data sharing across organizational boundaries due to loss of control, power and independency. Organizational issues are thus considered one of the fundamental constraints to inter-organizational sharing of spatial data. 相似文献
74.
基于Wilson模型的物流空间相互作用 总被引:3,自引:1,他引:3
从产生原理的角度、用修正的wilson模型刻画物流空间相互作用.根据该模型获得"作用强度"和"相互作用负荷"两个参数.作用强度的大小能够反映物流服务供给的合理与否;相互作用负荷增大的空间相互作用方向是进行物流设施建设的主要方位,由相互作用负荷的变化确定的物流设施的规划建设在空间方位上表现出交替性. 相似文献
75.
Political pressures and the credibility of regulation: can profit sharing mitigate regulatory risk? 总被引:1,自引:0,他引:1
When price-cap rules determine the structure of prices for a long period, they suffer a credibility problem and introduce
an element of risk especially if a firm’s profits are “too large”. Profit sharing may be seen as a device to pre-determine
price adjustments and thus to decrease regulatory risk. We analyse the effects of profit sharing on the incentives to invest,
using a real option approach. Absent credibility issues, a well designed profit sharing system may be neutral relative to
a pure price cap. With regulatory risk, profit sharing is preferable to a pure price-cap one, if it intervenes for high enough
profit levels.
相似文献
Carlo Scarpa (Corresponding author)Email: |
76.
《Spatial Economic Analysis》2013,8(4):467-483
Abstract This paper discusses the maximum likelihood estimator of a general unbalanced spatial random effects model with normal disturbances, assuming that some observations are missing at random. Monte Carlo simulations show that the maximum likelihood estimator for unbalanced panels performs well and that missing observations affect mainly the root mean square error. As expected, these estimates are less efficient than those based on the unobserved balanced model, especially if the share of missing observations is large or spatial autocorrelation in the error terms is pronounced. Estimation de vraisemblance maximale d'un modèle général d'effets aléatoires spatiaux déséquilibré: une étude Monte Carlo RÉSUMÉ La présente communication se penche sur l'estimateur du maximum de vraisemblance d'un modèle général d'effets aléatoires spatiaux déséquilibré avec des perturbations normales, en supposant l'absence aléatoire de certaines observations. Des simulations de Monte Carlo montrent que des groupes déséquilibrés se comporte bien, et que les observations manquantes affectent principalement l'erreur de la moyenne quadratique. Comme prévu, ces évaluations sont moins efficaces que celles qui sont basées sur le modèle équilibré non observé, notamment si la part des observations manquantes est importantes, ou l'on déclare une autocorrélation spatiale dans les termes d'erreur. Estimación de la probabilidad máxima de un modelo espacial general desequilibrado de efectos al azar: un estudio de Monte Carlo RÉSUMÉN Este trabajo discute el estimador de probabilidad máxima de un modelo espacial general desequilibrado de efectos al azar con alteraciones normales, suponiendo que faltan algunas observaciones al azar. Las simulaciones de Monte Carlo muestran que el estimador de probabilidad máxima para los paneles desequilibrados funciona satisfactoriamente, y que las observaciones omisas afectan principalmente al error de la media cuadrática. Como se suponía, estas estimaciones son menos eficientes que las basadas en el modelo equilibrado inadvertido, especialmente si la cantidad de omisiones es grande/o la autocorrelación en los términos de error es pronunciada. 相似文献
77.
78.
企业如果想要在质量上更上一层楼,就必须对于工程资料予以足够重视。本文以工程资料的作用为切入点,详细论述了其在信息查询、项目监管、项目信息、项目成果以及项目后期建设的作用和意义。 相似文献
79.
《Telecommunications Policy》2018,42(8):622-635
Future 5G networks aim at providing new high-quality wireless services to meet stringent and case-specific needs of various vertical sectors beyond traditional mobile broadband offerings. 5G is expected to disrupt the mobile communication business ecosystem and open the market to drastically new sharing based network operational models. 5G technical features of network slicing and small cell deployments in higher carrier frequencies will lower the investment barrier for new entrants to deploy local radio access networks and offer vertical specific services in specific areas and allow them lease the remaining required infrastructure on demand from mobile network operators (MNO) or infrastructure vendors. To realize the full vision of 5G to benefit the society and promote competition, innovation and emergence of new services when the 5G end-to-end network spans across different stakeholders administrative domains, the existing regulations governing the mobile communication business ecosystem are being refined. This paper provides a tutorial overview on how 5G innovations impact mobile communications and reviews the regulatory elements relevant to 5G development for locally deployed networks. This paper expands the recent micro licensing model for local spectrum authorization in future 5G systems and provides guidelines for the development of the key micro licensing elements. This local micro licensing model can open the mobile market by allowing different stakeholders to deploy local small cell networks with locally issued spectrum licenses ensuring pre-defined quality guarantees for the vertical sectors’ case specific needs. 相似文献
80.
Recent theoretical developments in the domain of strategic groups, specifically those related to cognitive groups and strategic group identity, seem to suggest that strategic group membership is likely to be relatively stable over time and that firms in a strategic group co‐evolve. Yet appropriate data analytic approaches that use information about firms over time to identify stable strategic groups and their evolutionary paths have been lacking. To overcome such limitations, this research proposes a new clusterwise bilinear multidimensional scaling model that can simultaneously identify (1) the number of strategic groups, (2) the dimensions on which the strategic groups are based, and (3) the evolution of the strategy of these groups over time. Our discussion encompasses various alternative model specifications, together with model selection heuristics based on statistical information criteria. An illustration of the proposed methodology using data pertaining to strategic variables for a sample of public banks in the tristate area of New York, Ohio, and Pennsylvania across three time periods (1995, 1999, and 2003) identifies two underlying dimensions with five strategic groups that display very different evolutionary paths over time. Post hoc analysis shows pronounced differences in firm performance across the five derived strategic groups. This article concludes with a discussion of the implications of the findings, as well as potential future research directions. John Wiley & Sons, Ltd. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献