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Bong Gyou Lee Jeong Ho Kwak Ki Youn Kim Seong Jin Kim 《Telecommunications Policy》2009,33(5-6):296-308
In 1996, the Korean mobile communication market was the first in the world to commercialize the code division multiple access (CDMA). Since then, the voice-based mobile phone market has continued to grow and has now reached near saturation. Having recognized the potential of the mobile data service as a new source of profit, telecommunication operators are scrambling to evolve 3.5 generation (3.5G) technology in order to lead market competition. Recently, the Korean 3.5G mobile telecom market has faced stiff competition from CDMA-based EVDO Rev.A and global system for mobile telecommunications (GSM)-based high-speed downlink packet access (HSDPA). In addition, the world's first wireless LAN-based wireless broadband internet (WiBro) service was commercialized in June, 2006. This paper reviews the current status of the 3.5G technology and analyzes the service standardization strategies from the viewpoint of technological evolutions. This paper also suggests implications for Korea's specific circumstances where different mobile telecom technologies complement and compete with one another. Korea's experiences may serve as important lessons for other countries or operators who try to introduce the 3G and look beyond mobile telecom technologies. 相似文献
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Chi-Yo Huang Author Vitae Author Vitae 《Technological Forecasting and Social Change》2008,75(1):12-31
Product life cycle (PLC) prediction plays a crucial role in strategic planning and policy definition for high-technology products. Forecast methodologies which can predict PLCs accurately can help to achieve successful strategic decision-making, forecasting, and foresight activities in high-technology firms, research institutes, governments, and universities. Over the past few decades, even though analytic framework strategies have been proposed for production, marketing, R&D (research and development), and finance, aiming at each stage of PLCs, forecast methodologies with which to predict PLCs are few. The purpose of this research is to develop a novel forecast methodology to allow for predictions of product life time (PLT) and the annual shipment of products during the entire PLC of multiple generation products. A novel two-stage fuzzy piecewise regression analysis method is proposed in this paper. In the first stage, the product life-time of the specific generation to be analyzed will be predicted by the fuzzy piecewise regression line that is derived based upon the product life-time of earlier generations. In the second stage of the forecast methodology, the annual shipment of products of the specified generation will be predicted by deriving annual fuzzy regression lines for each generation, based upon the historical data on the earlier generations' products. An empirical study predicting the life-time and the annual shipment of the 16 Mb (Mega bit) DRAM (Dynamic Random Access Memory) PLC is illustrated to validate the analytical process. The results demonstrate that two-stage fuzzy piecewise regression analysis can predict multiple generation PLT and PLC precisely, thereby serving as a foundation for future strategic planning, policy definitions and foresights. 相似文献
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Björn Nykvist Author Vitae Lorraine Whitmarsh Author Vitae 《Technological Forecasting and Social Change》2008,75(9):1373-1387
A wide range of intractable problems such as polluting emissions, noise, accidents, resource depletion, and inaccessibility of amenities are associated with the current transport regime. Given the slow movement towards a more sustainable mobility system, more radical, systemic innovation - a ‘transition’ - is required. Broadly speaking, this may be achieved via three routes: technological change, modal shift, and reduced travel demand. Drawing on concepts from the transitions literature (e.g., [Geels, F.W.: Technological Transitions and System Innovations: A Co-evolutionary and Socio-Technical Analysis, Edward Elgar, Cheltenham, 2005.]), we conceptualise each of these routes as a bundle of niche activities within an Area of Innovation, deviating to differing degrees from the current mobility ‘regime’. We present empirical evidence and indications of ongoing development of niches in these three areas within the UK and Sweden, and explore processes of co-evolution, divergence and tension within and between niches. Findings indicate recent market penetration of novel transport technologies, more advanced than modal shift or demand management activities; however, different transport technologies are more successful in each country. We also identify examples of a close relationship between development of radical vehicle/fuel technologies and provision of mobility services; and information technology as a driver in all three areas of innovation. We conclude that future innovation in transport depends on diversity, hybridisation, and co-evolution of niches. Finally, policy implications are discussed. 相似文献
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Jonathan D. Linton Author Vitae 《Technological Forecasting and Social Change》2008,75(5):583-594
Many see Nanotechnology as the technology that will underlie the next Schumpeterian wave creating new opportunities for wealth and job creation. Further it is a process based or materials technology. Yet all currently used models of innovation are based on assembled products or service products and these simply do not recognize the differences in materials products nor the “enabling” nature of Nanotechnologies. If nanotechnology is poised to become the economic engine of this millennium and if current models of innovation, which are utilized, by policy makers and firm based strategist alike are based on technology product paradigms that are dissimilar to the realities of nanotechnology and other process-based technologies then there is cause for concern.Here the authors provide a model and supporting cases demonstrating a new process or materials based innovation model that is based on the tight coupling between product and process innovation of not only Nanotechnology-based products but other process-based products. This is an important finding, because it identifies and remedies a gap in the literature associated with earlier process and product innovation models. For process-based products like materials, food, chemicals and nanotechnologies any change to the manufacturing processes results in significant changes in end product features. The implications of this model to practice are considered. 相似文献
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土地革命是中国民主革命的基本内容,毛泽东在领导中国新民主主义革命运动中,一直较关注中国农民土地问题的彻底解决,并建立健全了一系列有关土地问题的法律制度,它对今天的土地立法和发展农村经济,建设有中国特色的社会主义土地法律制度有指导意义。 相似文献
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Cheng Jin -chuan 《上海商学院学报》2003,(1)
本文分析了入世后,上海企业家在做大商业品牌中,应正确处理好的六个关系,以及有关的述评。 相似文献
29.
Jin E. Zhang 《期货市场杂志》2003,23(6):535-560
This article explores the price of continuously sampled Asian options. For geometric Asian options, we present pricing formulas for both backward‐starting and forward‐starting cases. For arithmetic Asian options, we demonstrate that the governing partial differential equation (PDE) cannot be transformed into a heat equation with constant coefficients; therefore, these options do not have a closed‐form solution of the Black–Scholes type, that is, the solution is not given in terms of the cumulative normal distribution function. We then solve the PDE with a perturbation method and obtain an analytical solution in a series form. Numerical results show that as compared with Zhang's ( 2001 ) highly accurate numerical results, the series converges very quickly and gives a good approximate value that is more accurate than any other approximate method in the literature, at least for the options tested in this article. Graphical results determine that the solution converges globally very quickly especially near the origin, which is the area in which most of the traded Asian options fall. © 2003 Wiley Periodicals, Inc. Jrl Fut Mark 23:535–560, 2003 相似文献
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一、商业银行信用风险管理的主要模型和方法商业银行传统的信用风险度量方法有信贷决策的“6C”法和信用评分方法等。“6C”法是指由有关专家根据借款人的品德(character)(借款人的作风、观念以及责任心等,借款人过去的还款记录是银行判断借款人品德的主要依据);能力(capacity) 相似文献