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排序方式: 共有612条查询结果,搜索用时 15 毫秒
1.
Cycle time forecasting (CTF) is one of the most crucial issues for production planning to keep high delivery reliability in semiconductor wafer fabrication systems (SWFS). This paper proposes a novel data-intensive cycle time (CT) prediction system with parallel computing to rapidly forecast the CT of wafer lots with large datasets. First, a density peak based radial basis function network (DP-RBFN) is designed to forecast the CT with the diverse and agglomerative CT data. Second, the network learning method based on a clustering technique is proposed to determine the density peak. Third, a parallel computing approach for network training is proposed in order to speed up the training process with large scaled CT data. Finally, an experiment with respect to SWFS is presented, which demonstrates that the proposed CTF system can not only speed up the training process of the model but also outperform the radial basis function network, the back-propagation-network and multivariate regression methodology based CTF methods in terms of the mean absolute deviation and standard deviation.  相似文献   
2.
This study draws on customer-dominant logic and self-expansion theory to examine the drivers of customer engagement behaviors in the context of emerging online interest communities. The engagement behaviors seen in online communities are operationalized into four types: augmenting, co-developing, influencing, and mobilizing. Goal pursuit (gratifying-the-self, enabling-the-self, and enriching-the-self) and emotional attachment to the community are found to be the key antecedent factors of these behaviors. The attainment of gratifying-the-self has a direct influence on these behaviors, whereas the attainment of enabling-the-self and enriching-the-self influences them via emotional attachment to the community.  相似文献   
3.
在广义空间调制(GSM)系统中,最大似然(ML)检测可以取得最优的检测性能,然而其计算复杂度随激活天线数的增加急剧增长。针对这一问题,提出了一种基于稀疏重构理论的低复杂度检测算法——正则化正交匹配追踪(ROMP)算法。该算法首先根据信道矩阵和当前残差的内积选取多个候选激活天线索引,接着对候选天线索引按正则化标准进行可靠性验证,剔除错误索引,缩小信号的搜索空间,最后通过求解最小二乘问题估计信号。仿真结果表明,与经典的正交匹配追踪(OMP)算法相比,所提算法以少许复杂度的增加为代价极大提升了检测性能,能够在检测性能与复杂度之间取得更好的折中。  相似文献   
4.
基于ANP-PP-SPA的区域洪灾风险评价模型研究   总被引:1,自引:0,他引:1  
针对现有洪灾风险评价模型的缺陷与不足,从致灾因子、孕灾因子、承灾因子和减灾因子4个方面,通过对14项评价指标的分析与计算,构建洪灾风险评价体系。洪灾风险评价体系以网络层次分析法(ANP)求解主观权重,投影寻踪法(PP)求解客观权重,主客观综合权重与集对分析理论(SPA)耦合,构建基于ANP-PP-SPA的洪灾风险评价模型。以广东省英德市为例,验证洪灾风险评价模型的适用性。计算结果表明,英德市2016年的洪灾风险属于中等级别,符合英德市2016年的实际情况。洪灾风险评价模型不仅综合考虑了评价指标间的相互关系,还较好地体现了洪灾风险的模糊性和随机性,能够为区域洪灾风险决策和洪水管理提供科学依据。  相似文献   
5.
In 2017, the Chinese government implemented a national strategy of "Rural Vitalization" that sought to realize full-scale rural vitalization. However, is it possible to achieve vitalization for all the villages in China? How should their development potential be determined? This paper identified and analyzed the "element-composite" messages of rural development based on 99 exemplary sites of “Beautiful Villages” in China. Combined with the projection pursuit classification method, a diagnostic system of rural vitalization was established; then, Dehua County was taken as a case study for an in-depth analysis. Based on national data analysis, the final results indicated that livelihood resources (LR), agglomeration effects (AE), location and transportation (LT), cultural/natural landscapes (CN), and economic circumstance (EC) are essential elements for successful rural development. Additionally, EC was the only exogenous element, while the remaining elements were endogenous. Furthermore, the villages with better EC presented urbanization rates of 38∼82 % and Engel coefficients of 29∼41 % in their counties; exemplary sites lacking LR, CN, LT, and AE account for 13.13 %, 19.19 %, 26.26 %, and 60.61 % respectively, so the indispensability of these elements decreases progressively in sequence. Only 2 % of villages rely on single element for success, therefore, the composite pattern of development element was also critical; 10 out of 16 types were found to successfully facilitate village development, among which, the type of R-a-L-C (32.32 %) and R-A-L-C (15.15 %) were considered as the greatest potential patterns for vitalization. Finally, by means of the diagnostic system, the ratio of representative villages for high-low potential in Dehua County is evenly split; then, development paths, and land use policies that match with paths were proposed, on the basis of development potential and “element-composite” condition of themselves.  相似文献   
6.
新制度经济学中的委托代理理论基于“经济人理性”假定,设计出了精密、精巧、精致的委托代理制度,有效化解了现代企业中委托人与代理人之间利益冲突并提升了企业运营效率。然而,现代企业实践已经证明,即使委托代理制度十分精密、精巧、精致,仍然没有彻底解决委托人与代理人之间的利益冲突和企业运营效率进一步提升问题。因此,必须拓展既有理论视野,从“经济人理性”假定拓展到“经济人+社会人+家庭人复合理性”假定,这样就能够实现委托代理理论视野的拓展。运用新制度经济学研究方法和双边对称信任数理模型表明:基于委托代理制度,进一步强化委托人与代理人之间双边对称信任度,可以进一步化解他们之间的利益冲突并且改善企业运营效率。基于这一结论,强化委托人与代理人之间双边对称信任度的具体路径是优化社会信任环境系统。  相似文献   
7.
We disentangle asset-specific, market, and funding liquidity in the CDS–bond basis outside and during the 2007–9 global financial crisis. Our findings stress the importance of separating different types of liquidity, since all three measures have independently negative impacts on the basis. Funding liquidity emerges as the economically most important liquidity metric. While asset-specific liquidity is cross-correlated in both the cash and derivative markets, funding and market liquidity only matter for the cash market. We exploit the decomposition of the basis to test predictions of limits-to-arbitrage theories. We find strong evidence in favor of margin-based asset pricing and flight-to-quality effects.  相似文献   
8.
董哲  佟旭  王咏梅  张莹  张林 《价值工程》2014,(34):313-315
本文主要探讨了脑静脉和静脉窦血栓形成的影像学研究现状,论述了脑静脉系统血栓形成的解剖基础以及CVST的影像学检查。  相似文献   
9.
This paper examines whether commodity futures risk factors can predict future economic growth. We test risk factors capturing various spot or term premia and find that only three factors capturing term premia on the basis-momentum, basis, and change in slope are robust predictors for future economic growth, especially for long horizons. Our findings highlight the importance of the term premia, rather than the spot premia on which the literature has mainly focused. Moreover, we find that possible explanations for predictability of commodity factors—the intertemporal asset pricing model and information diffusion explanation—are all inconsistent with our empirical results.  相似文献   
10.
This paper analyses interbank risk using the information content of basis swap (BS) spreads, floating-to-floating interest rate swaps whose payments are associated with euro deposit rates for alternative tenors. To identify the impact of shocks affecting interbank risk, we propose an empirical model that decomposes BS quotes into their expected and unexpected components. These unobservable constituents of BS spreads are estimated by solving a signal extraction problem using a particle filter. We find that expected components covariate with aggregate liquidity and risk aversion while systemic risk arises as the main driver behind unexpected fluctuations. Our empirical findings suggest that macroprudential analysis emerges as a key device to ease asset pricing in a new multi-curve scenario.  相似文献   
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