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1.
为了提高双离合变速器在车辆上的换挡品质,提升电气化换挡执行机构的工作效率,给出执行机构性能与换挡品质评价准则;通过两种不同双离合变速器电控电动执行机构的工作原理与性能分析,基于MATLAB数值仿真方法优化出最高效率进行试验.基于车辆6个维度的换挡工况对二者所搭载的变速器分别进行试验与CAN线数据采集,对比研究两种机构优缺点,通过雷达图的方式进行优劣说明.结果表明,两种执行机构传动效率可达70%且换挡品质相当.可见Tip in tip out工况对二者要求最为严格.  相似文献   
2.
This study addresses current gaps in the empirical literature regarding the effect of diplomatic representation on trade using a panel data set for 100 countries with 5‐year interval data from 1985 to 2005 and four‐digit level industry data. The results indicate that the effect of diplomatic representation on exports in differentiated goods is positive and significant and larger than on exports in homogeneous goods on average, but not statistically different from it. Furthermore, diplomatic representation only increases trade along the extensive margin and not along the intensive margin. The results indicate that diplomatic representation is effective in performing its function as a network search intermediary and that it is a useful policy tool to alleviate market failure.  相似文献   
3.
One of the most robust stylized facts in macroeconomics is the forecasting power of the term spread for future real activity. We propose a possible causal mechanism for the forecasting power of the term spread, deriving from the balance sheet management of financial intermediaries and the “risk‐taking channel of monetary policy.” Monetary tightening leads to the flattening of the term spread, reducing net interest margin and credit supply. We provide empirical support for the risk‐taking channel.  相似文献   
4.
[目的]科学合理的适宜性评价是确保耕地整理能够有效开展的前提条件,同时对于我国的耕地保护与粮食安全保障也具有极为重要的意义。[方法]该研究首先选取可以反映区域耕地整理适宜性的指标因子,然后参考胡学东提出的约束条件评价模型,引入区域生态安全和社会经济双重约束,对研究区域在双重约束下的耕地整理适宜性进行评价,并通过K-Means聚类法将研究区域的耕地整理适宜性分区进行合理划分。[结果]生态安全约束和社会经济约束对区域耕地整理适宜性水平具有重大影响,高生态安全约束与高社会经济约束会降低耕地整理的适宜性,低生态安全约束与低社会经济约束会提高耕地整理的适宜性。[结论]引入生态安全约束和社会经济约束后,可以在一定程度上反映山地区域在社会经济与生态安全双重约束状态下的耕地整理适宜性情况,耕地整理适宜性评价结果更加符合当地实际情况,约束条件评价模型可以更加合理准确地对处于约束条件下的耕地整理适宜性进行评价,是对耕地整理适宜性评价方法的丰富与完善。  相似文献   
5.
为了解决航空发动机双通道电子控制器(EEC)两个通道均发生故障时如何评估通道健康度,从而选择主控通道的问题,论文提出了基于逆模型计算发动机推力敏感度的方法,量化不同信号故障对发动机推力的影响程度,依据推力敏感度来评估双通道健康度,协助主控通道选择,最终提高系统的安全性。  相似文献   
6.
The present inquiry focuses on the modernization perspectives of the commodity‐exporting countries through the lens of development economics. To this end, the study adopts the Kaldorian framework to address the modernization effects, epitomized in the absorption of surplus labor. To trace the process of economic modernization, the study augments Lewis’s dualistic economy model by the extractive sector. Three different scenarios for the management of resource revenues are scrutinized. An altruistic mode, which implies a pure redistribution of the revenues among the poor swaths of the population, protracts the process of economic modernization, requires a greater amount of capital stock, and harbors a greater risk of a poverty trap. This effect is less pronounced if the modern sector is more capital‐intensive. A productive mode, which elicits full reinvestment of the commodity revenues, in contrast, accelerates the pace of economic modernization. Further, predicated on the scrutiny of a more realistic scenario, a bargaining mode, the study derives the condition for a net positive (or negative) modernization effect. The study identifies technical progress alongside capital accumulation as a further important source of economic modernization.  相似文献   
7.
Social categorization is predominately assumed to have negative effects on the prosocial behavior of host country national (HCN) employees toward expatriates in foreign subsidiaries. Challenging this assumption, I draw on the common ingroup identity model to propose that dual identity – simultaneous identification with membership in a subgroup and in a superordinate group – reduces HCNs’ intergroup biases and facilitates prosocial behavior. More specifically, I hypothesize that HCNs’ organizational identity has a moderating effect on the positive relationship between HCNs’ expatriate outgroup categorization and dual identity, such that this relationship is weaker when organizational identity is low. Furthermore, I hypothesize that dual identity mediates the relationship between expatriate outgroup categorization and two prosocial behaviors: information sharing and affiliative citizenship behavior. Results from the data collected from 1,290 HCN employees in Japan provide support for these hypotheses and the moderated mediation model.  相似文献   
8.
针对目前职业教育产教融合综合指数不高、学生硬核实力与实际岗位脱节、教师四大职能与行业企业实践脱节以及育人目标与产业需求存在“隐形壁垒”等问题,对接产业链、人才链和创新链,校企双方从专业组建、基地建设、课程开发、技术创新、团队打造、人才培养等方面协同共建,构建了多方共享的产教融合育人平台,打造产教融合型的命运共同体。  相似文献   
9.
Low productivity growth in New Zealand has been a paradox. We study New Zealand firms’ profitability, in terms of profit margin and return on assets (ROA), from the viewpoints of productivity enablers using firm-level panel data. We find that tangible fixed investment and a research and development (R&D) tax incentive are associated with higher profitability performance. In addition, the firm size is found to be a key determinant of profit margin. By contrast, we do not find any evidence that intangible investment can improve the profitability. The global financial crisis has not changed the leverage effect on ROA in New Zealand, while the impact of R&D became more prominent after the crisis.  相似文献   
10.
立足国有企业具有社会和经济双重目标的理论逻辑,本文选取2007~2016年A股国有上市公司作为研究样本,分析了独立董事网络和国有股比例对投资效率的影响以及调节效应。研究发现:独立董事网络降低了国有上市公司的投资效率,较高比例的国有持股抑制了投资效率,但当国企更加关注经济目标时,则有助于改善投资效率;进一步研究发现,相比于特定功能类企业,独立董事网络在商业竞争类企业中发挥投资效率的改善作用更加显著。因此,独立董事应因地制宜在国企中发挥治理作用;政府应分类推进国企混合所有制改革;竞争性国企应引入较大比例的优质民营资本,优化投资决策、提高投资效率。  相似文献   
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