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51.
Landscape is defined by the European Landscape Convention as “an area perceived by people, whose character is the result of the action and interaction of natural and/or human factors”. Many efforts have been devoted in addressing the core concepts on which this definition roots: perception and interaction of men and nature, but when coming to large (continental) scale assessments, the latter prevail on the former.This paper aims at presenting a framework for a measurable landscape awareness indicator as a key link to the public demand for a specific type of landscape: the agricultural landscape. This is a necessary effort to complement more physically based assessments, which include as well the impact of human activities on landscapes.The analysis is carried out at different levels of governance: EU and regional, using an example from the Alentejo region in Portugal and EU wide databases, and addresses conceptual and practical questions: what type of societal landscape awareness can be monitored and by whom (e.g., individuals, specific social groups, society as a whole); what are the landscape dimensions that should be assessed; what are the limitations imposed by data-related constraints. By applying the methodology to build composite indicators to map landscape societal awareness, the paper shows the regional and local meaning of indicator approaches developed at European level, presents developments for downscaling to regional level, while introducing the social component to support sound policy development for European rural landscapes.  相似文献   
52.
当前,国际碳基金运营体系日趋成熟。本文总结了国际碳基金在治理运营模式、风险评价、风险控制与项目退出四个方面的运营经验;并结合实际,提出了中国进一步发展碳基金的建议。  相似文献   
53.
This paper presents an application of the Multi-Scale Integrated Analysis of Societal and Ecosystem Metabolism (MuSIASEM) approach to the analysis of rural land uses. Using secondary data on farming systems in Laos, we illustrate how the concept of metabolic pattern can be used to establish links between the various indicators of performance of rural systems. To this purpose, we characterize the socioeconomic activities in rural Laos by a series of quantitative indicators defined across: (i) different hierarchical levels of organization described at different scales (i.e. households, rural villages, administrative regions and the whole country) and (ii) different dimensions of analysis, including economic, agronomic, social, biophysical, and ecological analysis. The MuSIASEM approach simultaneously employs two non-equivalent criteria for quantification. The observed rural system is described in terms of an integrated set of flow elements (money, food, energy, water, fertilizer and other materials), which are mapped against two distinct fund elements: (i) a multi-level matrix of human activity (flows being expressed in terms of intensity per hour) and (ii) a multi-level matrix of land uses (flows being expressed as density per hectare). Our case study shows that in this way it is possible to move across different hierarchical levels, scales and dimensions, to arrive at an integrated representation of the metabolic pattern of farming systems.  相似文献   
54.
Australia's largest cities are more mono-centric than most US cities and may be over-centralising, particularly in terms of office employment. Government worker relocation programs are being employed with policy debate over what should be an ideal urban structure including in terms of travel behaviour. The paper explores research approaches to explore transport impacts of employment decentralization. A review shows the results of: surveys of workers moved to suburban locations; longitudinal analyses of transport and land use changes in city-regions using cross-sectional census or HTS data; comparative analysis of urban structure variables across cities using similar datasets; combinations of longitudinal and comparative research; and, scenario-based modelling approaches. A modelling framework is then developed to appraise the possible transport impacts of decentralization in Brisbane. To test the possibilities further, two decentralization scenarios modelled and compared. Decentralization mostly to middle-suburban locations better addresses jobs-housing balance and maximises proposed new public transport services, producing good transport outcomes. However, decentralization to outer-suburban locations in Brisbane exacerbates the propensity for decentralization to increase travel distances, especially by car.  相似文献   
55.
In this article, the author proposes an innovative, exam-based homework grading method to facilitate both collaboration among students and individual accountability while learning a complex theory and applying it to solve a problem. Results from this novel approach to grading a comparative advantage theory homework assignment, using an objective exam performance measure to adjust original homework grades, show that students increase their comprehension of the frequently misunderstood theory. This novel grading method can be applied in a variety of contexts to promote student collaboration in preparation of academic work while providing incentives to encourage individual accountability and engagement.  相似文献   
56.
To avoid the current paradoxes of the global agro-food system it is necessary to define and implement a viable agricultural sustainable model, combining satisfaction of food needs and land preservation. A possible solution can be found in a holistic production system consistent with a sustainable development model, designed to satisfy diverse “local” economies. The conservation agriculture (CA) could be a part of this model, as it includes a set of best practices available to preserve agrarian soil and its biodiversity. Briefly, we cover the CA background in Europe followed by the evaluation of its impact in terms of private/public interest, using the sustainability’s metric.To test the viability of a model based on CA in “local conditions”, we compare economic performance of different conservation practices (i.e. minimum and no tillage) to that of conventional agriculture in a typical Mediterranean environment – Collina Materana – in Southern Italy (Basilicata region). Our findings suggest that: i) CA can actually be a viable alternative to conventional systems; ii) in Mediterranean agricultural areas CA has yield advantages especially during dry years, when conservation techniques increase water supply to crops; iii) public support is needed to direct farming choices in fact without financial incentives these practices would be not widely accepted and diffused; iv) European policy makers have to recognized the positive benefits of CA and pay them as ecosystem services in the framework of Good Agricultural Environmental Conditions and the present CAP subsidies.  相似文献   
57.
The knowledge of a product's life cycle is the first step on the search of sustainable development. The life cycle assessment (LCA) is an important method because it allows an environment accounting, where the extraction of natural resources and energy of the nature are considered and the "returns" to the same one and allows in evaluating relative potential the environment impacts generated. The present work had as objective to make an analysis of material and energy flows of the life cycle of three types of packaging for soft drinks: glass bottles of 390 mL, aluminum cans of 350 mL, and bottles of PET of 2,000 mL. The study considered processes since the extraction of raw materials for production of the packaging until the stages of recycling, after the consumption of the soft drink. For the research, an inventory analysis followed the LCA methodology. The main critical points of generation of negative environmental impact during the life cycle of each packaging had been the identified and quantified data in this study. The consumption of natural resources like water and other raw materials and energy, the generation of atmospheric emissions, solid wastes and wastewaters had been the analyzed categories. The results showed that, in accordance with the scenes and defined variables, the most important conclusion was that the bottle of glass presented a less favorable scene to the environment in comparison with other packaging.  相似文献   
58.
Though most landscape ecologists have integrated scaling issues in their works, these issues are often disregarded in landscape perception and preference studies. Researchers base their studies on a predefined single scale to assess the landscape, and they pay little attention to the scale specificity of their analysis and recommendations. We reconsidered three landscape assessment studies from our research unit in light of scaling issues. In addition to the scale of the assessed landscape, researchers should address the scale of the landscape surrogate that is submitted for assessment, including the spatial references of the people surveyed and the target level of application of the results. Indeed, many of the landscape assessment methods mix different landscape notions and scales. Therefore, we recommend the cautious use of these assessments, the integration of qualitative insights in addition tithe scoring and paying attention to the perception scale, as defined by Fairclough (2006).  相似文献   
59.
郭凤琼 《价值工程》2015,(21):51-52
并购是企业为了扩大生产规模、提高经营效益所做出的重大战略调整。本文运用账面价值法,将企业各种因素赋予不同的权重,结合账面价值倍数参数(支付者愿意支付的净资产价值的倍数)评估企业的价值,得到了更为客观的企业价值参数,为并购决策提供了可靠的参考依据。  相似文献   
60.
The present study examines the location of emergency rescue problems for urban ambulance and railway emergency systems. The proposed model considers probabilistic rescue demand, independent busy fractions of ambulances, and the corresponding risk levels in railway segments. We formulate the proposed model using fuzzy multi-objective programming and solve it using a generic algorithm and a non-dominated sorting genetic algorithm-II. Computation results are analyzed by applying the model to a real-world Taiwan railway system. Analytical results demonstrate that a proper adjustment of the rescue resource location improves rescue effectiveness for railway rescue and urban medical service demand.  相似文献   
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