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991.
New Zealand is the only country to date to have implemented forced ownership unbundling of electricity distribution from the rest of the electricity supply industry (in 1998). This paper examines the impact of this policy on electricity prices, quality of service and costs. We find that ownership unbundling did not achieve its objectives of facilitating greater competition in the electricity supply industry but that it did lead to lower costs and higher quality of service. We suggest that this experience indicates the potential benefits of ownership unbundling in Europe but also the danger of unintended consequences.  相似文献   
992.
Antitrust authorities have imposed firewalls between the previously separate divisions of newly vertically integrated firms in several industries, to address concerns that access to horizontal rivals’ proprietary information may reduce competition. This paper evaluates a specific antitrust concern by modeling the price effect of one seller’s learning its rival’s production costs before bidding in a duopoly procurement contest. The results show that imposing a firewall as a condition for permitting a vertical merger actually can lead to higher prices than if the flow of information were unimpeded, and they provide guidance as to when this unintended outcome occurs.  相似文献   
993.
This paper measures the impact of the entry of large supermarkets on incumbents of various sizes. Contrary to the conventional notion that big stores drive small rivals out of the market, data from Tokyo in the 1990s show that large supermarkets’ entry induces the exit of existing large and medium-size competitors, but improves the survival rate of small supermarkets. These findings highlight the role of store size as an important dimension of product differentiation. Size-based entry regulations would appear to protect big incumbents, at the expense of small incumbents and potential entrants.  相似文献   
994.
Creativity is acknowledged to be important for economic growth and as an everyday life-skill, however several influential reports have suggested that education could do more to harness creative talent. Creative cognition literature suggests the lack of creativity is at least partly the result of ‘fixation’ (difficulty in generating novel ideas due to imagination being ‘structured’ by existing knowledge). This paper focuses on the secondary (students aged 11–16 years) design and technology (D&T) context in the UK. Here we examine whether teacher practice can contribute to fixation by focusing on one specific facet of teacher practice in D&T; the use of product analysis to inform the generation of creative design ideas. Data is drawn from the preliminary phase of a research and intervention project from interviews with D&T teachers (N = 14), students (N = 126) and lesson observations (N = 10) and an analysis of documents and student work. Product analysis is widely used at different points in design projects but, as is shown, in all cases current practice can lead to fixation, as thinking is constrained down specific paths and tasks are at best at procedural rather than comprehension level. The implications of these findings and tentative ways forward for practitioners are discussed.  相似文献   
995.
This study investigates what pupils aged 10–12 can learn from working with robots, assuming that understanding robotics is a sign of technological literacy. We conducted cognitive and conceptual analysis to develop a frame of reference for determining pupils’ understanding of robotics. Four perspectives were distinguished with increasing sophistication; “psychological”, “technological”, “function”, and “controlled system”. Using Lego® Mindstorms® NXT robots, as an example of a Direct Manipulation Environment, we developed and conducted a lesson plan to investigate pupils’ reasoning patterns. There is ample evidence that pupils have little difficulty in understanding that robots are man-made technological and functional artifacts. Pupils’ understanding of the controlled system concept, more specifically the complex sense-reason-act loop that is characteristic of robotics, can be fostered by means of problem solving tasks. The results are discussed with respect to pupils’ developing technological literacy and the possibilities for teaching and learning in primary education.  相似文献   
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The Emission Trading Schemes of China and Europe show that China’s envisaged national ETS could bring a major contribution in the international approach against global warming; new perspectives on the use of composite sustainability indicators are also highlighted. China’s regional pilot schemes will converge to a (more) uniform price of emission allowances. As China is a major economic and political actor in the world economy, China’s progress with ETS is important. At the same time, China’s progress in the field of green international competitiveness – standing for a positive revealed comparative advantage in environmentally friendly goods – in the period 2000–2015 is considerable and the improved positioning of China in the EIIW-vita sustainability indicator shows considerable technological dynamics in Asia. The European ETS is working, but it suffers from the rather low price of emission allowances. The long-term time horizon of 2050 in the EU climate policy is rather ambitious and it is unclear whether or not a consistent G20 approach can be achieved – with the EU, China, Japan and the US cooperating amongst each other. There is a lack of a specialized climate stabilization institution in the world economy, the traditional anchoring of climate policy in the UN weakens the practical pressure for efficient cooperation since the UN is very heterogeneous in terms of per capita income and GHG emissions per unit of GDP; G20 might be an institution that is suitable for effective policy cooperation. More initiatives in the field of recycling could be useful.  相似文献   
1000.
Effects of direct flights on trade costs are investigated using micro price data at the city level. After controlling for local retail/distribution costs, traded input prices are obtained to be further used in the measurement of trade costs across cities through arbitrage conditions. The existence of a direct flight enters trade costs regressions negatively and significantly. The results are shown to be robust to the consideration of many control variables, nonlinearities in the effects of distance on trade costs, possible endogeneity of having direct flights between cities and alternative definitions of the data. The direct flights that are shown to be determined by bilateral air services agreements are further shown to reduce trade costs through an endogeneity analysis; the main policy implications are twofold: (i) international trade policies through aviation services, such as Open Skies Agreements of the US, are alternative trade policy tools to reduce international trade barriers; (ii) direct flights facilitate the integration of internal markets as in the case of European Union.  相似文献   
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