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1.
孙英潮 《科技和产业》2021,21(2):238-242
基于严寒区京沈客专朝阳试验段路基基床的温度监测资料分析,研究不同厚度聚氨酯保温板对高速铁路路基混凝土基床温度变化特性影响.测试结果表明:①铺设聚氨酯保温板能够有效阻断严寒区环境与路基基床间的热量传递,保温效果与板厚相关;②地温大多数时间呈阳高阴低现象,同时阴、阳坡路基温差波动幅度随埋深逐渐减小;③基床表层阴、阳面各测点的温度变化起始时间一致,而阴面的冻结时间比阳面晚一个月.由此表明,保温板能够有效降低环境与混凝土道床之间的热交换,但是对路基阴、阳坡的影响存在差异.建议在严寒地区高速铁路路基阳、阴坡可以采取不同厚度的聚氨酯保温板,减小阴阳坡地温差异,保持季冻土路基温度变化稳定.  相似文献   
2.
随着我国电网逐渐向智能电网迈进,信息技术在电能传输、转换、分配、调度等方面的应用,使电力企业可以进行结构调整,提高电力系统管理水平。据统计,2011年,我国电力信息化投资达220亿元,2012-2015年,电力工程建设稳步推进。为了促进电力企业全面开展项目成本核算和有效控制,提高电力工程项目的效益,确定了典型方案设计模块,通过定额规则库与典型方案设计相匹配的方法,解决了安装过程中定额第一版遗留的一些问题,并通过设计选型等措施加强了成本控制。  相似文献   
3.
《Business Horizons》2019,62(4):427-436
While financial reporting standards under U.S. GAAP and IFRS are fundamentally similar, differences do exist that may affect our analysis of company financial statements. This is particularly true when comparing a U.S. company following U.S. GAAP to a firm that uses IFRS. To illustrate, we compare research and development (R&D) accounting methods under both sets of standards and illustrate how they affect the analysis of financial results of firms in a specific industry—automotive manufacturers. Our results provide insight into settings in which differences in R&D accounting may have the greatest impact on financial analysis.  相似文献   
4.
In this paper, we investigate the impact of oil prices on both aggregate and industry US real stock returns over the period 1973–2017. The empirical analysis contributes to the related literature introducing a state-dependent oil price (high and low) and the local projections approach. Our main finding is that, depending on the nature of the shock and industry, the negative effects of oil price shocks become exacerbated -and the positive effects get moderated- if oil prices are already high.  相似文献   
5.
Luby变换(Luby Transform,LT)码作为信道编码应用于电力线通信(Power Line Communication,PLC),可实现电信号的可靠传输。度分布对LT码编译码性能的影响至关重要。为了得到更优的度分布,首先调整二进制指数分布(Binary Exponential Distribution,BED)中的度数比例,获得一种译码性能更优的改进的二进制指数分布(Improved BED,IBED)。然后,根据IBED在冗余度较小时译码成功率高,而冗余度增大后鲁棒孤子分布(Robust Soliton Distribution,RSD)的译码性能表现更佳的特点,通过求和归一化的方式将IBED与RSD两种度分布的优势进行有机结合,提出一种新型二进制鲁棒孤子分布(Binary RSD,BRSD)。仿真结果表明,与其他方法及传统的RSD相比,采用新度分布进行LT编码,可明显降低译码开销,并节约编译码耗时。将新型度分布应用于基于LT码的PLC系统中,能有效地抑制PLC信道中各种噪声对电信号的干扰,并提高通信效率。  相似文献   
6.
I investigate the long-run relationship between corruption and innovative activity using annual data from 48 contiguous U.S. states between 1977 and 2006. Using U.S. data allows me to work with a panel long enough to exploit time series properties of the data. I use two different measures of innovative activity: one measuring the quantity and the other measuring the quality of the patents granted. I also use two different measures of corruption: one based on the number of corruption convictions, the other based on number of corruption stories covered in Associated Press news wires. Following Pedroni (1999, 2000), I estimate the cointegrating relationship between corruption and innovative activity with Fully Modified Ordinary Least Squares (FMOLS). The results indicate that corruption indeed slows down innovation in the long-run.  相似文献   
7.
This article uses a multi-country global general equilibrium (GE) model to numerically simulate the effects of possible China–US trade wars. We introduce an endogenous trade imbalance structure with trade cost into the model which helps to explore both tariff and non-tariff trade war effects. Our simulation results show that China will be significantly hurt by the China–US trade war, but negative impacts are affordable. The US can gain under unilateral sanction measures to China, but will lose if China takes retaliation measures. Comparing the effects under mutual trade war, China will lose more than the US. Introducing non-tariff barrier trade wars will intensify the negative effects, and comparatively negative effects to China are larger than to the US. Mexico’s involvement in trade war with the US will strengthen the negative effects and comparatively hurt the US more. Under non-cooperative and cooperative Nash bargaining equilibrium, the US can gain more than China in trade war negotiation, which means the US has stronger bargaining power than China. Additionally, trade wars between China and the US will hurt most countries and the world especially in GDP and manufacturing employment, but benefit their welfare and trade.  相似文献   
8.
According to everyone average welfare value of land resources; this paper constitutes the base line of glebe usufruct deal value by analyzing the factors, which are affecting glebe usufruct deal value. Having adopted share's quotient of ownership and contracting power, the paper erects assigning mechanism to the income of glebe deal. Because of the share dynarnicity being adopted which shows the flexible strong points, the shares of ownership and contracting power avoid many unnecessary otiose disputes on income of glebe deal, adding the stability to the glebe usufruct deal. It is beneficial to the freedom flow and validity manufacture factor installment and also to the nonagricultural changing course.  相似文献   
9.
This paper develops and estimates models of family and sex-specific emigration, as well as the sex composition of this emigration, from 12 European source countries to the U.S. for the period 1870–1910. The models are based on the distinction between economic migrants (males, single females, and some married females) and tied or trailing migrants (females) and are estimated with panel data, including data that relate to the occupational/industrial structure of male and female economic activity in source countries. Hausman-Taylor instrumental variable estimates suggest that although both males and females responded to labor-market signals, males were more responsive than females to per capita GDP differences. Moreover, compared to the rest of Europe, Ireland, and Scandinavia were the sources of many young, single male, and female migrants, who responded strongly to gaps in economic opportunities. In fact, much of the European response to such gaps appears to be due to migrants from Ireland and Scandinavia. Females tended to originate in English-speaking countries and countries that were agriculturally oriented. Service and manufacturing jobs in source countries discouraged the migration of females relative to males. Males tended to follow recent migrants more than females, but females responded more to long-term influences as measured by stocks of migrants from their source countries who had previously settled in the U.S. Countries with high birth rates had relatively fewer female emigrants, whereas those with high rates of natural increase 20 years earlier experienced relatively more male emigration. Intact families, other family members (including family-strategy male migrants and trailing female migrants), and single males and females responded strongly to economic incentives, but the singles were most responsive followed by family-strategy males.  相似文献   
10.
WARWICK FUNNELL 《Abacus》1994,30(2):175-195
The principles of state audit, in particular conceptions of independence, adhered to today in the major Westminster democracies originated in the British state audit reforms of the nineteenth century. State auditors prior to the nineteenth century were not expected to be independent of the executive. Instead, state audit was recognized as an executive function to be under the direct control of the executive. For a brief period in the mid-nineteenth century, parliament was able to take advantage of a succession of weak governments to redirect the loyalties of state audit from the executive to the legislature. Although parliament wanted to be served by a state auditor who would keep it informed of executive spending, it did not alter the dominance of the Treasury over state audit. The executive sought to sustain through a discourse of independence the perception that the controls exercised by the executive over the state auditor did not constitute either a threat to audit independence or result in capture of state audit by the executive. The discourse constructed the image of state audit as a function which was able to work unimpeded and independent of the executive despite a legislative framework which contained significant financial, procedural and staffing controls.  相似文献   
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