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31.
加入世界贸易组织三年来,我国全面履行了农产品国际贸易方面的入世承诺,农产品的进出口都得到了迅速的发展,取得了良好的成绩。通过分析入世以来我国农产品贸易的发展状况、面临的问题和发展趋势,提出未来我国农产品贸易发展的应对策略,以利于我国经济更加健康地融入世界经济。  相似文献   
32.
财政分权与义务教育财政管理体制问题探析   总被引:2,自引:0,他引:2  
我国是成功实施财政分权化的国家之一。作为公共财政框架部分之一的义务教育也实行了分权化管理,义务教育办学的责任主要地落在了县、乡两级地方政府身上。而我国庞大的义务教育事业由县、乡甚至村脆弱的财力来承担,可谓“杯水车薪”:一些农村地区和贫困山区学龄儿童无学可上,无书可读等现象屡见不鲜。可见过度分权化的义务教育财政管理体制是制约当今中国义务教育发展的症结所在。  相似文献   
33.
产业结构和就业结构的变化反映出区域经济发展的资源分配结构及其发展进程和水平.分析发现,万州区与涪陵区在产业结构上都存在第一产业所占比重与其吸纳劳动力的比重不一致的现象,其中,涪陵区第二产业比重较大但吸纳劳动力能力较弱,而万州区第三产业吸纳劳动力能力要弱于涪陵区.两地应大力发展第三产业以改善就业结构,充分吸纳从第一产业转移出来的劳动力.  相似文献   
34.
In this study, water temperature longitudinal and temporal patterns were investigated in four locations of the Yangtze River to identify their influence on spawning of the Chinese sturgeon (Acipenser sinensis Gray 1835). The results showed that, historically (1960–1980), the four locations, Pingshan (PS, 2,687 river kilometres [rkm]), Yichang (YC, 1,640 rkm), Chenglingji (CLJ, 1,265 rkm), and Hukou (HK, 805 rkm), all had similar average annual water temperatures (around 18.0 °C) but very different amplitudes: The upper two locations, PS (11.4–23.2 °C) and YC (9.1–25.9 °C), were relatively stable and had smaller amplitude than the lower two ones, CLJ (6.0–30.0 °C) and HK (5.9–30.8 °C). On the basis of the physiological effects for Chinese sturgeon, we defined three water temperature ranges: stressing (>23 °C), holding (23–20 °C), and spawning (20–16 °C). We found that the upper two locations with successful spawning of the Chinese sturgeon (PS and YC) had short or no stressing period but long holding and spawning periods. Currently (2013–2016), the impoundment of the Three Gorges Reservoir increases the time for water temperature decreasing to 20 °C at the current spawning ground (YC) in autumn, which increases the stressing and holding periods, and has significant negative impact on the spawning of Chinese sturgeon. Nonetheless, considering the very high stressing temperature and the short duration of the holding and spawning periods at CLJ and HK, we propose that YC is still the most suitable spawning location for the Chinese sturgeon.  相似文献   
35.
为了探究深部巷道围岩的分区破裂化现象,利用ANSYS/LS-DYNA软件数值模拟,使用Cowper-Symonds本构模型结合GISSMO模型,将巷道的开挖视为动力过程。从岩石的细观角度出发,考虑岩石的应变率效应以及损伤对岩石的力学性质的影响,构建应变率损伤本构模型。同时结合应力三轴度,以更全面地描述岩石在各种应力条件下的力学特性,并基于最大应变和最大拉应力准则建立单元破坏准则。对岩石进行单轴压缩数值、掘进开挖法模拟及实际观测的结果表明:岩石单轴压缩全应力-应变曲线拟合效果较好;掘进开挖速率对分区破裂化现象有影响;掘进开挖法的分区破裂化模拟结果与实际观测数据具有一定的一致性。提出的模型对于围岩分区破裂化现场的模拟及预测有一定的参考意义。  相似文献   
36.
We propose a unit root test for panels with cross-sectional dependency. We allow general dependency structure among the innovations that generate data for each of the cross-sectional units. Each unit may have different sample size, and therefore unbalanced panels are also permitted in our framework. Yet, the test is asymptotically normal, and does not require any tabulation of the critical values. Our test is based on nonlinear IV estimation of the usual augmented Dickey–Fuller type regression for each cross-sectional unit, using as instruments nonlinear transformations of the lagged levels. The actual test statistic is simply defined as a standardized sum of individual IV t-ratios. We show in the paper that such a standardized sum of individual IV t-ratios has limit normal distribution as long as the panels have large individual time series observations and are asymptotically balanced in a very weak sense. We may have the number of cross-sectional units arbitrarily small or large. In particular, the usual sequential asymptotics, upon which most of the available asymptotic theories for panel unit root models heavily rely, are not required. Finite sample performance of our test is examined via a set of simulations, and compared with those of other commonly used panel unit root tests. Our test generally performs better than the existing tests in terms of both finite sample sizes and powers. We apply our nonlinear IV method to test for the purchasing power parity hypothesis in panels.  相似文献   
37.
Since the passage of the Science and Technology Basic Law in 1999, Taiwanese universities have taken a more “scientific-economic” approach to protect and commercialize their research. This research mainly examines innovation activities such as patenting, licensing, and incubated startups in the context of Taiwanese higher education institutions (HEIs). The “scientific-economic” framework used to analyze the strategic aspects influencing these academic innovations includes (1) intellectual property managerial capabilities, (2) the strength of external industrial partnerships, (3) the university entrepreneurial orientation, and (4) government research policy. Four hypotheses were developed. Data were collected via a questionnaire with all 122 HEIs in Taiwan surveyed.The research reveals that the aspects of intellectual property managerial capability, HEI-industry partnerships, and academic entrepreneurial orientation are useful to distinguish the university's innovation performance on patent grants, licensing incomes, and firm incubation. Also, government support on research plays a moderating role in academic innovation. Managerial and policy implications for managing innovation effectively in universities were drawn.  相似文献   
38.
企业发展以“多元化”战略为好,还是“专业化”战略为重?作简单地“肯定一个,否定一个”式的评判显然是不科学的,也是无济于事的。上世纪90年代中期以前,多元化的名声非常响亮,随着1997年金融危机中韩国大型多元化企业集团的纷纷衰落,多元化开始成为千夫所指的罪魁祸首。而恰恰在此时,我国的不少企业也因多元化发展陷入困境甚至破产了: 巨人集团总裁史玉柱反省其失败的四大失误之一就是盲目追求多元化经营。巨人公司涉足的电脑业、房地产  相似文献   
39.
Summary. It is commonly argued that poorly designed banking system safety nets are largely to blame for the frequency and severity of modern banking crises. For example, underpriced deposit insurance and/or low reserve requirements are often viewed as factors that encourage risk-taking by banks. In this paper, we study the effects of three policy variables: deposit insurance premia, reserve requirements and the way in which the costs of bank bailouts are financed. We show that when deposit insurance premia are low, the monetization of bank bailout costs may not be more inflationary than financing these costs out of general revenue. This is because, while monetizing the costs increases the inflation tax rate, higher levels of general taxation reduce savings, deposits, bank reserves, and the inflation tax base. Increasing the inflation tax rate obviously raises inflation, but so does an erosion of the inflation tax base. We also find that low deposit insurance premia or low reserve requirements may not be associated with a high rate of bank failure.Received: 2 January 2002, Revised: 1 March 2003JEL Classification Numbers: D5, E5, G1.B. D. Smith: Sadly, our co-author, colleague and dear friend, Bruce D. Smith, died on July 9, 2002.  相似文献   
40.
This paper uses a modification of the continuous time asset pricing model of Cox, Ingersoll, and Ross to analyze the effect of regulatory risk on the cost of capital. Analysis shows that random errors in setting the allowed rate of return can either increase or decrease the cost of capital depending on other regulatory parameters. However, the analysis suggests that regulatory risk is not material.  相似文献   
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