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51.
精神文明建设是社会主义的重要特征,其直接目的是为了全面提高人的素质,发展和推广科学技术,为物质文明的发展提供精神动力、智力支持和思想政治保证,从而推动生产力的发展。因此,精神文明建设也是解放和发展生产力。  相似文献   
52.
Chinese history is littered with sharp policy swings, and the communist era, which has not yet fully drawn to a close, has witnessed a veritable embarrassment of riches. This has provided a fertile ground for researchers engaged in crystal ball gazing. Recently, momentum has accelerated on that front, a development apparently reflecting the increasingly fluid political‐economic conditions in the country. The scenarios generated can serve as an effective reference point in planning exercises, but there is scope for solidifying the conceptual architecture. The issue of rendering them highly relevant to foreign investors, presumably very important potential consumers of the product, should also be addressed.  相似文献   
53.
俄罗斯大力推行国防科技工业企业一体化,并在许多领域,特别是在电子技术和信息技术领域都采取了许多有效的措施。同时国家政策倾向于对国防工业进行各种形式融资支持,其实践经验对中国有所启示。  相似文献   
54.
Most industrial countries have experienced a transformation of land use: from decreasing to expanding forest areas, the so-called forest transition. Outside closed forests, European rural landscapes exhibit a diversity of tree-based agricultural systems, but the question of whether this forest transition has also affected ‘trees outside forests’ has rarely been studied. The aim of this study is to analyze the spatial-temporal dynamics of farm trees and woodlands in an agricultural landscape in Eastern Germany from 1964 to 2008, based on aerial photographs and digital orthophotos. Taking a landscape ecological perspective, we quantify farm tree dynamics, disentangle processes of gain and loss in the socialist and post-socialist periods of Eastern Germany, and assess differences in ecosystem services provided by farm trees. A substantial increase of overall tree cover by 24.8% was observed for the selected time period, but trajectories have been disparate across different farm tree classes. The increase in tree cover was stronger in steep valleys than on hills and plateaus, indicating a significant interdependence between topography and trajectories of change. Patch numbers of farm trees did not increase, which suggests that the expansion of tree cover is mostly due to a spatial expansion of previously existing tree patches. Overall net gains in tree cover were rather similar during the socialist and post-socialist eras. The general increase in tree cover was accompanied by increase in agriculture-related ecosystem service provision, but the increase in pollination and pest control services was much lower than that in water purification services. These findings present the first empirical evidence from an industrialized country that there is also an ongoing ‘forest transition’ outside closed forests. Potential, partially counteracting drivers of change during the socialist and post-socialist periods have mainly been related to farm policies and the environmental consciousness of land users and society as a whole.  相似文献   
55.
王洋 《中国渔业经济》2012,30(2):156-165
本文旨在研究海水环境中刚性封闭箱体水产养殖系统的潜在设计工序。封闭箱体水产养殖技术通过限制并操控养殖鱼类与外部水环境相互作用以将环境影响最小化。系统的箱体单元通常紧密排布并锚泊到海底。研究关注的地理区域在加拿大不列颠哥伦比亚省乔治亚海峡。本文研究了含多个单元的箱体水产养殖系统的设计构造。设计程序包括检验以下内容:当地环境条件;多个箱体单元上受到的阻力;波浪荷载;无阻尼升沉运动;锚泊设备组件;刚性控制结构的材料应力。还讨论了操作以及其它设计要素。初步研究结果表明波浪力是至关重要的。  相似文献   
56.
文章在系统总结发展中国家对外直接投资历程的基础上,结合发展中国家FDI出现的新特点,认为发展中国家的对外直接投资除已出现学习型FDI、竞争策略型FDI以外,极少数发展中国家的跨国公司已开始进入更为高级的市场势力型FDI阶段。  相似文献   
57.
This paper proposes a systematic accounting framework to decompose the reallocation of labour out of agriculture into factor market distortions and market-driven forces. The findings are twofold. First, the removal of factor market distortions is a dominant driving force of the structural change in China in the last decades, which contributes 50.52%, and market-driven forces account for the rest 49.48%. Second, the contribution of market-driven forces has been increasing with the deepening of market-oriented reforms, while the impact of the removal of factor market distortions has been decreasing especially along with the slowdown of labour market reforms after China joined the WTO in 2001. The results imply that further reforms that aim at correcting factor market distortions could still be an important impetus of structural change in the future.  相似文献   
58.
介绍了战场频谱态势感知及频谱筹划系统的系统功能、组成、工作过程、关键技术及解决途径,通过分析指出频谱态势感知及频谱筹划系统与C4ISR系统集成可提高战场频谱管理的整体能力。  相似文献   
59.
In the recent interest for the so-called entrepreneurial university, there is a strong emphasis on academic (i.e. theoretical) knowledge to be used more effectively as a source of innovation and renewal in industry. Drawing on a theoretical framework developed by the literature theorist Mikhail Bakhtin and a study of 10 research centres in a major technical university, this paper suggests that rather than representing something radically new, the entrepreneurial university is a domain wherein traditional academic research interests and industry objectives are continuously negotiated and mutually adjusted. Seen in this view, the entrepreneurial university is what is always in a process of becoming, in flux and change, continuously under the influence of opposing and complementary goals and objectives. Therefore, the entrepreneurial university is not a solid state or an entrenched position but the effect of an attitude towards the role and purpose of the university in the so-called knowledge society.  相似文献   
60.
由土地利用变化导致的生态系统服务价值的变化可以作为一个反映土地利用变化环境效应的重要 量化指标。该文参考谢高地等人提出的单位面积生态服务价值系数,对涞水县2001~2010年的土地利用变 化及其对生态系统的影响和驱动因素进行了分析研究。结果表明,2001~2007年和2007~2010年土地利用 类型变化差异较大。2001~2007年,耕地面积有大幅减少,林地、草地面积大幅增加,2007~2010年,耕 地、草地、居民点及工矿用地面积增加明显,园地、林地、滩涂和裸地减少;2007~2010年的土地利用变 化率明显高于2001~2007年;由于林地、滩涂面积的减少和居民点及工矿用地面积的增加,使得整个研究 期生态系统服务价值净减少4 024.47万元;整个研究期间内各项生态系统服务功能都出现不同程度的衰 退。农用地和非农用地经济生态位在研究期内呈波动变化,导致其两者的差值也呈波动变化。驱动因素分 析表明,前期政策因素影响较大,后期社会经济指标对生态系统起负向作用。由于该区特殊的地理位置和 相对薄弱的经济基础,该区域迫切需要处理好经济发展与生态环境的关系,提高土地利用集约度,合理调 整产业结构,进一步完善生态补偿机制等以实现区域生态建设与经济发展互促双赢。  相似文献   
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