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891.
The front end phase of the new product development has been examined extensively, yet few if any studies have examined the front end phase of new process development. By means of a multiple case study of process firms, this article aims to bridge this knowledge gap. Our results show that substantial differences in front end activities exist between the product development and process development domains. We conceptualize the front end in process development to be an iterative trial-and-error process, dominated by activities such as idea generation and refinement, literature reviews, anticipation of end-product changes, and various forms of experiments in bench scale, lab scale, and full-scale production. In addition, we highlight key problems in the front end and managerial remedies for how to mitigate them. While these findings provide theoretical implications for research into product development, process development and production management, the findings are particularly relevant to process development managers, plant managers, and development engineers interested in increasing the efficiency of production processes.  相似文献   
892.
We assess the marginal predictive content of a large international dataset for forecasting GDP in New Zealand, an archetypal small open economy. We apply “data-rich” factor and shrinkage methods to efficiently handle hundreds of predictor series from many countries. The methods covered are principal components, targeted predictors, weighted principal components, partial least squares, elastic net and ridge regression. We find that exploiting a large international dataset can improve forecasts relative to data-rich approaches based on a large national dataset only, and also relative to more traditional approaches based on small datasets. This is in spite of New Zealand’s business and consumer confidence and expectations data capturing a substantial proportion of the predictive information in the international data. The largest forecasting accuracy gains from including international predictors are at longer forecast horizons. The forecasting performance achievable with the data-rich methods differs widely, with shrinkage methods and partial least squares performing best in handling the international data.  相似文献   
893.
Based on formal results for population dynamics under varying fertility and mortality levels, this paper presents a new approach to backward population projection. Unlike other methods in the literature, the method presented here is robust and accurate in both the short and long run. The method and the theory behind it contribute to the knowledge about dynamic populations and may find applications in population modeling and reconstruction.  相似文献   
894.
This paper presents a novel intelligent bidding system, called SOABER (Simultaneous Online Auction BiddER), which monitors simultaneous online auctions of high-value fine art items. It supports decision-making by maximizing bidders’ surpluses and their chances of winning an auction. One key element of the system is a dynamic forecasting model, which incorporates information about the speed of an auction’s price movement, as well as the level of competition both within and across auctions. Other elements include a wallet estimator, which gauges the bidders’ willingness to pay, and a bid strategizer, which embeds the forecasting model into a fully automated decision system. We illustrate the performance of our intelligent bidding system on an authentic dataset of online art auctions for Indian contemporary art. We compare our system with several simpler ad-hoc approaches, and find it to be more effective in terms of both the extracted surplus and the resulting winning percentage.  相似文献   
895.
Forecast combination through dimension reduction techniques   总被引:2,自引:0,他引:2  
This paper considers several methods of producing a single forecast from several individual ones. We compare “standard” but hard to beat combination schemes (such as the average of forecasts at each period, or consensus forecast and OLS-based combination schemes) with more sophisticated alternatives that involve dimension reduction techniques. Specifically, we consider principal components, dynamic factor models, partial least squares and sliced inverse regression.Our source of forecasts is the Survey of Professional Forecasters, which provides forecasts for the main US macroeconomic aggregates. The forecasting results show that partial least squares, principal component regression and factor analysis have similar performances (better than the usual benchmark models), but sliced inverse regression shows an extreme behavior (performs either very well or very poorly).  相似文献   
896.
The innovation diffusion literature has established that the spread of a successful innovation over time typically follows a sigmoid curve. Therefore, the forecasting in this area has been monopolized by the use of well known aggregate diffusion models. Time series forecasting has been surprisingly neglected, as it provides mainly accurate short term forecasts. In this work, a method of exponential smoothing, the Holt's damped trend with a modification, is applied in recent broadband diffusion data of two large regions after the reach of the inflection point. As validated with holdback sample data ranging from 6 up to 30 months, the key for successful forecasting is the use of the estimated saturation level calculated from a diffusion model, in order to specify the appropriate trend. The results indicate improved predictions compared to two popular diffusion models, the Gompertz and the Linear Logistic model. The paper concludes with the application of the proposed method in a 48-month forecasting horizon, as well as the suggestions for further research.  相似文献   
897.
A key strength of backcasting is arguably the emphasis it places upon envisaging longer-term distant futures, allowing participants and users to think beyond incremental changes in their current lived experience and to embrace the more radical and disruptive socio-technical changes which may be necessary to deliver sustainability. In so doing, however, backcasting may run the risk of obscuring significant differences in current lived experience, negating alternative problem framings and normatively derived views of what constitutes sustainability. This paper reports an innovative UK attempt to develop an inclusive ‘bottom-up’ community foresight process for urban sustainability research. Unlike most backcasting studies, the methodology was initially grounded in an exploration of the community participants' current lived experience and understandings of sustainability. Given the particular purpose of the study the primary outcome from the work was structured around the articulation of a ‘community-led’ agenda for urban sustainability research, rather than an explicit normative vision and transition pathway. However, the methodology could easily be adapted for use in other contexts, and showed potential to contribute to the formation of local ‘transition arenas’: facilitating network formation and building capacity for local sustainability initiatives and experiments.  相似文献   
898.
A Delphi study was performed to answer the question: Which global societal trends relate to future radicalization and subsequent terrorism in the Netherlands? An inventory of two hundred global societal trends and a literature study of radicalization together served as briefing of the participants in the Delphi study. The first two rounds were conducted in anonymous writing. The third round was a face to face focus group meeting. In the first and second round participants scored the trends, adjusted their scores relative to others and provided arguments, and in the focus group meeting, themes were discussed in which the participants remained to have strong opposite views. This approach emphasizes divergence in opinion (‘dissensus’), as opposed to convergence (‘consensus’). Consensus seeking to us seems to be the dominant application of Delphi, but we emphasize the value of seeking dissensus. We hypothesize that in those cases where the opposite views that were discussed kept their ground, this Delphi study may have found early warnings of future radicalization.The essence of this paper is that it is possible, with limited effort, to get a handle on the complex and poorly defined subject of global societal trends influencing future radicalization. Application of the Dissensus Delphi method provided a selection of early warnings that may be looked into with future research.  相似文献   
899.
There are many uncertain factors in the high-tech project investment. It is necessary to use a scientific evaluation method in the high-tech investment. This paper proposes a risk evaluation method for a high-tech project investment. Firstly, the current situation of the research of a high-tech project investment is discussed. Then an evaluation indicators system is constructed and the evaluation procedure based on an uncertain linguistic weighted C-EOWA (ULWC-EOWA) operator is illuminated. Finally, this evaluation method is used in a practical example.  相似文献   
900.
This paper traces the translation processes associated with the mobilization of resources and industrial agency in the development of a next generation mobile network in Korea. To explain the socio-technical dynamics, the sociology of translation is used. The paper provides a story of a translation of strategy and related activities using Callon's four moments of translation. The story illustrates how, during the translation process, 4G strategies have been formed, shaped, and enhanced.It describes the process of technology adoption and developing stories by highlighting the co-evolving nature, diversity, and interface which constitute the next-generation network environment. It provides insight into the Korean mobile environment by offering a socio-technical analysis of 4G development and how it involves the dynamics of industry, regulation, and technology. The study suggests that the sociology of translation may be a promising explication of technological change and innovation.  相似文献   
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