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91.
We study whether pension fund managers, as professionals of important social and financial products, are able to add value for their clients and adapt to economic changes. To this end, we analyze the performance and skills (market timing and stock picking) over the economic cycle from both pension fund and manager perspectives. This double analysis allows examining whether skills reside in managers and/or funds and control for manager substitutions. Despite the long-term nature of pension funds, we find that both fund and manager skills vary with market conditions, showing better evidence of stock-picking in booms, and of market timing in recessions. Nonetheless, top (bottom) funds and managers exhibit both (incorrect) skills in booms and in recessions. Some of the top (bottom) funds and managers are the best (worst) in both abilities in the same periods, but not in different periods, showing that not all managers have the ability to adapt to market conditions. Additionally, managers with limited skills tend to specialize because diversification requires multi-task skills and the non-specialization of these managers usually results in incorrect skills.  相似文献   
92.
Information security management plays an essential role for drawing the roadmap of information security; thus, many theoretical methodologies and practical standards are brought into this domain. However, many standards and methodologies are too cumbersome to be adopted by an organization. Additionally, there is no unified framework to systematically handle the tedious tasks of information security management. This study’s primary goal is to design an integrated system for information security management (ISISM) that aims to use current methodologies and standards to solve the above-mentioned issues. Because business impact analysis and risk analysis are the most important areas within this domain, we carefully select the related methods and then integrate them into a unified framework, upon which the proposed ISISM depends. To achieve this outcome for this study, security requirement engineering is adopted, which enables the designed system to support system users in generating risk assessment reports with related information security policies.  相似文献   
93.
Providing nutritious and environmentally sustainable food to all people at all times is one of the greatest challenges currently facing society. This problem is particularly acute in Africa where an estimated one in four people still lack adequate food to sustain an active and healthy life. In this study, we consider the potential impact of future population growth and climate change on food security in Africa, looking ahead to 2050. A modelling framework termed FEEDME (Food Estimation and Export for Diet and Malnutrition Evaluation) was used which was characterized to model the impacts of future climate changes (utilizing the Intergovernmental Panel on Climate Change Special Report on Emissions Scenarios projections) and projected population growth on food availability and subsequent undernourishment prevalence in 44 African countries. Our results indicate that projected rapid population growth will be the leading cause of food insecurity and widespread undernourishment across Africa. Very little to no difference in undernourishment projections were found when we examined future scenarios with and without the effects of climate change, suggesting population growth is the dominant driver of change. Various adaptation options are discussed, such as closing the yield gap via sustainable intensification and increasing imports through trade and aid agreements. These strategies are likely to be critical in preventing catastrophic future food insecurity.  相似文献   
94.
刘元铚 《价值工程》2014,(20):183-184
针对近几年施工企业安全形势严峻,安全管理急需转型的形势完成本文。本文通过对企业安全管理的内部能力与外部因素运用SWOT分析,阐述了施工企业安全管理战略从过去突击式的安全大检查到以预防为主的危险源辨识管控的转变。  相似文献   
95.
In the 1990s, the Democratic People’s Republic of Korea (North Korea) suffered from severe food shortages and large-scale deforestation, which triggered a stage of rural conservation reform. Since 2004, with support from the Swiss Agency for Development and Cooperation (SDC), North Korea’s Ministry of Land and Environmental Protection (MoLEP) has implemented a Sloping Land Management Program (SLMP). The SLMP established sloping land user groups and granted these groups the right to use marginal land for agroforestry development. This devolution of land rights from state control onto local groups is a landmark in North Korea, and this decentralization initiative has now expanded to over eight counties to involve thousands of households. It has also led to the launch of a National Agroforestry Policy and Strategy. Drawing from both qualitative and quantitative data collected from 2008 to 2014, this paper documents the process and effects of the SLMP. It argues that the decentralization reform in land management has contributed to not only food security with increased food crop diversity and productivity, but also notably forest recovery through an expansion of tree plantations and agroforestry practices on degraded sloping lands. However, an insufficient power transfer in the form of a lack of timber rights granted to the local user groups has hampered the effectiveness of the SLMP. There are also institutional and geopolitical challenges that are limiting further scaling-up of land-use decentralization across the country. The policy implication calls for more international investment as well as national land-use policy reforms in order to promote and facilitate further decentralization of sloping land management and to secure greater use rights for sloping land user groups.  相似文献   
96.
Shortfalls in global food production, coupled with the growing visibility of climate change's disruptive effects, have underlined for many observers the importance of devoting rural lands to their ‘optimal’ use, where they can make maximal contributions to the global imperatives of feeding the human population and maintaining vital environmental services. In this context observers have endorsed rural land use planning as a way to insure that, at least in theory, lands get devoted to their best uses. In practice, land use planning in the developing world has resembled ‘organized anarchy’. Small landholders with insecure land tenure, overseas investors seeking large land deals, NGOs representing indigenous peoples, government officials, and staff from international environmental NGOs and multilateral organizations have come together in strategic action fields to struggle over and sometimes negotiate land use plans for contested landscapes. These plans represent a strategic, spatially explicit response to the climate change–biodiversity–food security crisis.  相似文献   
97.
杜亚敏 《价值工程》2014,(10):196-197
移动电子商务带来便利的同时也带来了新的安全问题,设备的多样性和移动网络环境的复杂性使得确保移动电子商务交易安全更加困难,本文通过分析现阶段移动电子商务的交易模式,提出现有移动电子商务交易过程中存在的安全问题与安全隐患,最后提出了较为可行的解决方案。  相似文献   
98.
朱涛 《价值工程》2015,(1):205-206
数字资源的拥有者应该设计图书馆数字资源的防盗链方案,提升数字图书馆的防盗链能力。本文通过对数字图书馆的了解,进行数字图书馆防盗链设计的研究。  相似文献   
99.
Soil is a natural resource essential to human welfare by virtue of its numerous crucial functions. In the past, soil has been taken for granted because of its widespread, albeit finite, availability. However, now that world's population is projected to exceed ten billion before the end of this century, soil is increasingly perceived as a precious commodity. Consequently, soil is increasingly under pressure by rich private investors and governments within the poorest countries to satisfy appetites for food production and biofuel. A case study is used to explore the plausibility of soil being considered as ‘brown gold’. Based on the comparison of land use maps, we estimated the value in terms of resource from raw material, carbon sink and virtual calories of the productive soil lost during the period 2003–2008 in the Emilia-Romagna Plain, one of the most productive areas of Italy. More than fifteen thousand hectares of cropland underwent land use change – in particular urbanization – over the 6-year period with an implied loss of crop production potential equivalent to the daily calorific requirement of more than 440,000 people. Taking into account that Italy is no longer self-sufficient in food production, such a loss appears to be strategically significant. Perhaps more importantly, urbanization and soil sealing has had negative ramifications on environmental sustainability, on both local and broad scales, with increased consumption of public funds. A logical framework of the socio-economic impact of land use change has been compiled and is presented as a possible example of a policy relevant approach to managing productive soils as a finite resource.  相似文献   
100.
中国在现代化进程中面临着一些现代性问题的困扰,其中,贫富分化成为社会矛盾的焦点之一。改革开放以来,中国居民生活水平得到整体提升,但也出现了结构上的分化。造成贫富差距的原因是复杂多重的。其中,城乡二元体制造成了城乡资源分配不公和收入差距,垄断行业的存在则使得资源在少部分群体中集聚,加深了贫富之间的鸿沟。此外,中国的社会保障制度没能充分发挥其调节作用,使得部分底层群体无法解决温饱问题,造成"极贫"群体的出现。值得关注的是,单位体制下的既得利益者,在住房制度改革后又获得福利性住房,住房不公平由此产生财产不公平。国家对于不断拉大的收入差距主要采取宏观政策加以调控,改革财税制度和完善社会保障同时进行,但这并不能因此改变由城乡二元体制和垄断等所带来的必然结果,因而只能起到局部调节收入差距的效果,不能实现真正的社会公正。  相似文献   
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