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This paper employs the 2008 financial crisis as an empirical setting to examine how investment strategies of venture capitalists (VCs) vary in the presence of a liquidity supply shock, and what the performance implications of these strategies are for their portfolio startups. We show that while, on aggregate, funded startups receive no less financing during the financial crisis than in non-crisis times, VCs allocate relatively more resources to startups operating in the VCs’ core sectors. We show that this skew allocation follows from VCs choosing to double down on their core-sector investing, rather than by a changed mix of investors or startups during the financial crisis. These effects are strongest for early-stage startups, for which information problems are most severe. Furthermore, these results are driven by the investment strategies of more-experienced VCs. Building on these findings, we find superior ex post performance among crisis-funded portfolio startups operating in more-experienced VCs’ core sectors.  相似文献   
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The aim of this study was: (i) to group basketball players into similar clusters based on a combination of anthropometric characteristics and playing experience; and (ii) explore the distribution of players (included starters and non-starters) from different levels of teams within the obtained clusters. The game-related statistics from 699 regular season balanced games were analyzed using a two-step cluster model and a discriminant analysis. The clustering process allowed identifying five different player profiles: Top height and weight (HW) with low experience, TopHW-LowE; Middle HW with middle experience, MiddleHW-MiddleE; Middle HW with top experience, MiddleHW-TopE; Low HW with low experience, LowHW-LowE; Low HW with middle experience, LowHW-MiddleE. Discriminant analysis showed that TopHW-LowE group was highlighted by two-point field goals made and missed, offensive and defensive rebounds, blocks, and personal fouls; whereas the LowHW-LowE group made fewest passes and touches. The players from weaker teams were mostly distributed in LowHW-LowE group, whereas players from stronger teams were mainly grouped in LowHW-MiddleE group; and players that participated in the finals were allocated in the MiddleHW-MiddleE group. These results provide alternative references for basketball staff concerning the process of evaluating performance.  相似文献   
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Precision and reliability of timescales are of importance in many situations, in particular in satellite navigation systems (i.e., Galileo system). Motivated by the necessity to improve the precision and the reliability of such clock signals, we have explored the possibility to exploit control theory in clock steering methods. First of all we provide a more robust theoretical framework for the analysis of the process. Two novel control algorithms are here proposed aiming to meet metrological specifications. Numerical simulations have been performed in order to evaluate the performances of the new control systems.  相似文献   
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Demand and innovation in services: The case of mobile communications   总被引:1,自引:0,他引:1  
This paper aims to analyse the pricing strategies of mobile communications operators and examine the role of demand characteristics in the development of new tariff plans. In so doing, we depart from a traditional industrial organization approach to price discrimination and interpret new tariff plans as innovations. In the spirit of Schumpeter, we look at competition in this sector as depending upon this form of innovation, and we argue that, given the specific features of the industry, the development of new tariff plans is strongly related to the users’ characteristics and behaviour. Our main point is that in a context of uncertainty, demand affects firms’ innovative strategies in two ways: first, by providing information on user behaviour and by increasing the capability of market segmentation; and second, by providing the incentives to innovate. This argument is supported by an empirical analysis carried out on the basis of an original dataset which includes all the tariff plans on offer in the history of the Italian market between 1992 and 2005. We find that both a firm's installed customer base and the level of market saturation play a role in shaping firms’ innovative pricing strategies, in terms of the number and characteristics of the new tariff plans.  相似文献   
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This study presents the results of the microclimate monitoring of the Arch of Augustus. This is a monument from the Roman era, situated in an urban area in the Western Alpine region of Aosta Valley, Italy. Measurements were carried out on different monument positions, corresponding to the four faces and below the vault. The measurements refer to air and surface temperature, air relative humidity, wind speed and direction. The environmental conditions are described in order to underline the differences among the four faces of the monument and to explain the nature of the decay observed on the monument. The damage risk, caused by the occurrence of phenomena like freezing-thawing cycles, thermal stress and water condensation, is estimated by relating microclimatic conditions to the stone damage processes. The results are compared to the decay map and the correlation between damage and microclimate are finally discussed.  相似文献   
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ABSTRACT

We aimed to evaluate the changes in double poling (DP) kinematics due to a long-distance cross-country skiing race in athletes with different performance levels. A total of 100 cross-country skiers, belonging to 10 different performance groups, were filmed on flat terrain 7 and 55 km after the start line, during a 58-km classical race. Cycle velocity, frequency and length decreased from the best to the lower-ranked group, while duty cycle increased (all P <.001). Between track sections, cycle velocity and length decreased, duty cycles increased (all P <.001) while frequency was unaltered (P =.782). Group*section interactions resulted for cycle velocity (P =.005). Considering all the participants together, % change in cycle velocity between sections correlated with % change in length and duty cycle (all P <.001). Thus i) skiers in better groups showed longer and more frequent cycles as well as shorter duty cycles than skiers in slower groups; ii) throughout the race all the groups maintained the same cycle frequency while decreasing cycle velocity and length; iii) better groups showed a lower reduction in cycle velocity. Individually, a low reduction in cycle velocity during the race related to the capacity to maintain long cycles and short duty cycles.  相似文献   
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