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41.
湖南省农业生态与农业经济耦合性测度 总被引:3,自引:0,他引:3
[目的]考察湖南省近9年来农业生态与农业经济系统耦合发展现状,探究二者发展过程中的规律,以期找出二者协调发展模式,并为湖南省农业生态环境保护、农业经济发展提供决策依据。[方法]运用耦合协调度模型,基于熵权法为各指标进行客观确定权重,结合2007~2015年湖南省农业生态与农业经济发展的相关数据,确定农业生态与农业经济的耦合匹配分析模型,采用熵值赋权法确定各项指标的权重,构建农业生态—农业经济耦合协调评价指标体系。[结果]研究结果表明,2007~2015年湖南省农业生态与农业经济的耦合协调发展基本稳定,耦合度值均在0.9以上,二者呈协调发展趋势。其中,2014年和2015年二者的耦合度较高,分别为0.975 3和0.984 3,说明湖南省在这两年的农业生态与农业经济的协调性好,农业经济与农业生态能够相互有效促进彼此的发展。同时,仍需时刻关注生态环境的承载力,降低对自然资源的无序攫取,实现经济的可持续发展。 相似文献
42.
P. N. Pali M. Schut P. Kibwika L. Wairegi M. Yami P. J. A. van Asten 《国际农业可持续发展杂志》2018,16(3):272-285
Agricultural policies in sub-Saharan Africa have paid insufficient attention to sustainable intensification. In Uganda, agricultural productivity has stagnated with aggregate increases in crop production being attributed to expansion of cultivated land area. To enhance sustainable crop intensification, the Ugandan Government collaborated with stakeholders to develop agricultural policies using an evidence-based approach. Previously, evidence-based decision-making tended to focus on the evidence base rather than evidence and its interactions within the broader policy context. We identify opportunities and pitfalls to strengthen science engagement in agricultural policy design by analysing the types of evidence required, and how it was shared and used during policy development. Qualitative tools captured stakeholders' perspectives of agricultural policies and their status in the policy cycle. Subsequent multi-level studies identified crop growth constraints and quantified yield gaps which were used to compute the economic analyses of policy options that subsequently contributed to sub-national program planning. The study identified a need to generate relevant evidence within a short time 'window' to influence policy design, power influence by different stakeholders and quality of stakeholder interaction. Opportunities for evidence integration surfaced at random phases of policy development due to researchers’ ’embededness’ within co-management and coordination structures. 相似文献
43.
粮食安全与农业结构调整水平的协整分析*——以广东省为例 总被引:1,自引:0,他引:1
[目的]实现我国粮食安全与农业结构调整之间(即粮食增产和农民增收)关系的协调,较长时间以来是学界、政界关注的重要议题,但定量分析两者之间内在依存关系的研究一直欠缺。[方法]文章采用协整分析及Granger因果关系检验方法,以广东为例,对我国粮食安全(用粮食总产量来衡量)与农业结构调整水平之间的协整性及因果关系进行了研究。[结果]广东粮食总产量与反映农业结构调整水平的3个指标之间均存在长期均衡关系,且农作物播种面积中粮食作物面积对广东粮食总产量影响最大,每下降1%,粮食总产量下降0. 659 548%。短期内,反映农业结构调整水平的3个指标对广东粮食总产量的影响均存在波动,但由短期偏离拉向长期均衡的牵动作用均较弱。Granger因果关系检验表明农业在国民经济中的比重、农作物播种面积中粮食作物面积早期对广东粮食总产量产生单向影响,但影响程度相对较弱。[结论]提出应从农业结构调整以外的因素着手提高我国粮食安全水平,并通过调整农业区域结构去缓解我国粮食供求市场的结构性矛盾。 相似文献
44.
45.
范振林 《中国国土资源经济》2021,(3)
鉴于负债的确认和核算是自然资源资产负债表编制的重点和难点,文章以国内外矿产资源资产负债的存在及其表现为线索进行分析与探讨,研究矿产资源开发产生负债运行机理和负债核算范围及内容等,揭示出矿产资源在其负外部性作用下形成负债的机理,并根据负外部性效应将矿产资源开发产生的负债划分为耗竭性负债、生态环境负债和安全负债,同时将耗竭性负债、生态环境负债和安全负债的核算范围与现有法律法规相衔接,提高负债核算的可操作性和可推广性,为自然资源资产负债表编制和维护国家所有者权益提供技术支撑。 相似文献
46.
47.
Binlei Gong 《新兴市场金融与贸易》2018,54(15):3438-3453
The “industry nurturing agriculture” reforms and World Trade Organization accession led to dramatic growth in public expenditure and international trade in China’s agricultural sector. This article aims to estimate the effects of public expenditure and trade on agricultural productivity in China for 2004–2015. A semi-parametric production function with shape constraints is introduced to derive more accurate productivity before the productivity determinants are analyzed with an emphasis on public expenditure and trade. The empirical result shows that public expenditure and exports can effectively improve agricultural productivity, while imports have no significant effects. Policy implications are discussed in the context of supply-side reforms. 相似文献
48.
Payment for ecosystem services schemes (PES) are lauded as a market-based solution to curtail deforestation and restore degraded ecosystems. However, PES programs often fail to conserve sites under strong long-term deforestation pressures. Underperformance, in part, is likely due to adverse selection. Spatial adverse selection occurs when landowners are more likely to enroll parcels with low deforestation pressure than parcels with high deforestation pressure. Temporal adverse selection arises when parcels are enrolled for short time periods. In both cases, financial resources are allocated without having a sizeable impact on long-term land use change. Improving program performance to overcome these shortcomings requires understanding attributes of landowners and their parcels across large scales to identify spatial and temporal enrollment patterns that drive adverse selection. In this paper, we examine these patterns in Argentina’s PES program in Chaco forest, a global deforestation hotspot. Our study area covers 252,319 km2. Results from multinomial logistic regression models showed that large parcels of enrolled land and parcels owned by absentee landowners exhibit greater evidence of spatiotemporal adverse selection than smaller parcels or parcels owned by local landowners. Furthermore, parcels managed under land use plans for conservation and restoration are more likely to be associated with adverse selection than parcels managed for financial returns such as harvest of non-timber forest products, silviculture, and silvopasture. However, prior to recommending that PES programs focus on land uses with higher potential earnings, a greater understanding is needed of the degree to which these land uses meet ecological and biodiversity goals of PES programs. We suggest that increased spatial targeting of enrollment, along with enrollment of local landowners and further incentives for land uses that support conservation and restoration, could promote long-term conservation of forest lands. 相似文献
49.
《International Journal of Forecasting》2020,36(2):515-530
We develop a method for forecasting the distribution of the daily surface wind speed at timescales from 15-days to 3-months in France. On such long-term timescales, ensemble predictions of the surface wind speed have poor performance, however, the wind speed distribution may be related to the large-scale circulation of the atmosphere, for which the ensemble forecasts have better skill. The information from the large-scale circulation, represented by the 500 hPa geopotential height, is summarized into a single index by first running a PCA and then a polynomial regression. We estimate, over 20 years of daily data, the conditional probability density of the wind speed at a specific location given the index. We then use the ECMWF seasonal forecast ensemble to predict the index for horizons from 15-days to 3-months. These predictions are plugged into the conditional density to obtain a distributional forecast of surface wind. These probabilistic forecasts remain sharper than the climatology up to 1-month forecast horizon. Using a statistical postprocessing method to recalibrate the ensemble leads to further improvement of our probabilistic forecast, which then remains calibrated and sharper than the climatology up to 3-months horizon, particularly in the north of France in winter and fall. 相似文献
50.
Ying Zhang Ji Li Wenwen Song Wanxing Jiang Wanling Ding 《International Journal of Human Resource Management》2020,31(12):1594-1616
AbstractAs an important component of organizational human resource slack (HR slack), the slack of research-and-development (R&D) professionals has been studied by several authors. However, it remains unclear whether and how this small component of general HR slack, i.e. the slack of research-and-development professionals (RHR slack), may affect overall firm performance in an emerging economy without much R&D tradition or pro-R&D institutions. Based on two organizational theories, i.e. institutional theory and the resource-based view of the firm (RBV), we propose competing hypotheses on the relationship between RHR slack and firms’ accounting performance. We also examine whether the relationship between RHR slack and firm performance should be linear or curvilinear. Finally, we also test the relationship between RHR slack and other dimensions of firm performance. Several interesting findings have been obtained. For instance, neither the perspective based on institutional theory nor that based on RBV can fully predict all types of RHR slack-performance relationships, be these relationships linear or curvilinear. 相似文献