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1.
In open systems, firms give up their property rights to technologies and permit other companies to use these technologies. We ask how an incumbent's architecture choice affects social welfare by altering R&D competition among firms. More specifically, we ask whether an incumbent, by adopting an open system, can establish its socially inefficient technology as the market standard, while an entrant is developing a more efficient technology. It is shown that an incumbent has an incentive to preempt an entrant's competing technology by choosing an open system, but that the open system might result in a premature market standard.  相似文献   
2.
A feature transformation method based on domain knowledge for arti?cial neural networks (ANNs) is proposed. The method of feature transformation based on domain knowledge converts continuous values into discrete values in accordance with the knowledge of experts in speci?c application domains. This approach effectively ?lters data, trains the classi?er, and extracts the rules from the classi?er. In addition, it reduces the dimensionality of the feature space, which not only decreases the cost and time in the operation but also enhances the generalizability of the classi?er. The experimental results of the proposed approach will be compared and tested statistically with the results of the linear transformation method. The results show that the method of feature transformation based on domain knowledge outperforms the linear transformation in modelling of ANNs. Copyright © 2004 John Wiley & Sons, Ltd.  相似文献   
3.
This article explores the characteristics of venture business and entrepreneurs in Korea to (1) identify technology transfer activities, (2) analyze the differences between technology transfer in linear and nonlinear venture businesses, and (3) guide more effective venture business policy and strategy. This empirical assessment reveals that entrepreneurs have insightful evaluations about their resources and capacities as well as expectations with regard to functions and features of science parks and incubators. Respondents from “linear model”-based start-ups tend to be older and have higher education, employ more basic research and development (R&D) and have more R&D-oriented careers, and have more varied work experience than “nonlinear”-based start-ups. The functions and features of science parks and incubators were generally not considered a critical influence on start-ups nor on the growth of venture businesses. Accordingly, alternative venture-nurturing strategies are discussed as being key to accelerate venture businesses growth.  相似文献   
4.
In this paper, we examine a trader's order choice between market and limit orders using a sample of orders submitted through NYSE SuperDot. We find that traders place more limit orders relative to market orders when: (1) the spread is large, (2) the order size is large, and (3) they expect high transitory price volatility. A rise in informational volatility appears neither to increase nor decrease the placement of limit orders. We also find that a rise in lagged price volatility decreases the size of spread, which is driven by the increase in the placement of limit orders.  相似文献   
5.
Drawing on reversal theory (Apter, 2007), the current research proposes that internet users' metamotivational state (telic vs. paratelic) determines advertising interactivity's effectiveness. An online field experiment involving 141 Facebook and Twitter users tests this proposition. Research findings support telic state consumers form more positive attitudes toward a low-level interactive ad, whereas paratelic state consumers form more positive attitudes toward a high-level interactive ad. Further, this research shows that an arousal seeking tendency mediates the metamotivational state's impact on ad attitude.  相似文献   
6.
To gain a better understanding of online brand communities, this study has examined why people joined in online brand communities and whether there were some differences in the motivations of Internet users based on different cultures. Open-ended questions were asked to the community members from both South Korean Automobile Online Brand Communities (KAOBC) and American Automobile Online Brand Communities (AAOBC) in the first stage and then generated and utilized an online survey for the study. The study found that KAOBC members tended to have a stronger social network, business, and communication motivations than AAOBC members. As a primary motivation, information seeking is the strongest motivation for members of both KAOBC and AAOBC. They had a similar level of information motivation.  相似文献   
7.
The aim of this article is to examine the impact of stock exchange mergers on the degree of informational efficiency. For this purpose, we apply the generalized spectral shape test for the martingale difference hypothesis to the stock returns before and after the 31 domestic and cross-border mergers completed from 1997 to 2011. The test is conducted with moving subsample windows, allowing us to detect the periods of (in)efficiency, and thus to conduct a comparative analysis for pre-merger and post-merger periods. We find that higher levels of efficiency are less frequent than lower levels of efficiency after a stock exchange merger. We also find that the impact on the level of efficiency depends on a range of merger characteristics such as the level of development, size, geographical diversification and industrial diversification of stock exchange.  相似文献   
8.
This paper explores the benefits of extending the investment universe to commodity futures, from the perspective of momentum traders. We find that the growth-optimal portfolio includes negative (positive) weights on commodity futures losers (stock winners). Motivated by this finding, we construct a joint momentum strategy, buying stock winners and selling commodity futures losers, and show that it generates an average monthly return of up to 1.91% and provides much lower skewness (0.04) and kurtosis (1.27) than a traditional stock momentum strategy. It also greatly improves profitability, especially in unfavorable market states, and thus effectively manages tail risk.  相似文献   
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10.
Forest transition in South Korea: Reality, path and drivers   总被引:2,自引:0,他引:2  
While forest transition (FT) in South Korea began in 1955, when forest cover was only 35% of national land area, significant increases in both forest cover and growing stock really occurred in the early 1970s. Using reconstructed historical records, we empirically demonstrate that (1) FT in South Korea was mainly accomplished by the recovery of degraded, non-stocked forest; and (2) one-dimensional FT analysis using forest area alone has severe limitations in diagnosing meaningful changes in forest sustainability. The key driver of FT in South Korea was the government-led reforestation policy. The comprehensive reforestation plans, started in 1973, not only provided economic incentives to the general public by establishing clear quantifiable goals, they also promoted inter-agency cooperation and coordination, especially between the energy and forest sectors, to replace firewood with fossil fuels. These government-led efforts, accompanied by rural-urban migration, brought an increase in stocked forest area and a complementary rising average growing stock level. The case of South Korea shows that FTs can be cultivated in a relatively short period of time by a central authority, even with imperfect governance and low economic development.  相似文献   
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