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31.
Relative efficiency of R&D activities: A cross-country study accounting for environmental factors in the DEA approach 总被引:1,自引:0,他引:1
This paper applies the production framework associated with the data envelopment analysis (DEA) method to evaluate the relative efficiency of R&D activities across countries. R&D capital stocks and manpower are treated as inputs while patents and academic publications are considered as outputs. A three-stage approach, which involves using DEA for evaluating efficiency and using Tobit regressions for controlling the external environment, is applied to 30 countries in recent years. The results show that less than one-half of the countries are fully efficient in R&D activities and that more than two-thirds are at the stage of increasing returns to scale. Most countries have a more significant advantage in producing SCI cum EI publications than in generating patents. 相似文献
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Marital conflict and conduct problems in Children of Twins 总被引:3,自引:0,他引:3
Harden KP Turkheimer E Emery RE D'Onofrio BM Slutske WS Heath AC Martin NG 《Child development》2007,78(1):1-18
The Children-of-Twins design was used to test whether associations between marital conflict frequency and conduct problems can be replicated within the children of discordant twin pairs. A sample of 2,051 children (age 14-39 years) of 1,045 twins was used to estimate the genetic and environmental influences on marital conflict and determine whether genetic or environmental selection processes underlie the observed association between marital conflict and conduct problems. Results indicate that genetic and nonshared environmental factors influence the risk of marital conflict. Furthermore, genetic influences mediated the association between marital conflict frequency and conduct problems. These results highlight the need for quasiexperimental designs in investigations of intergenerational associations. 相似文献
34.
Rebecca Hayes Caroline Godwin Danielle Butts Florence Martin 《Performance Improvement》2015,54(7):26-33
Suzy Q's is a retail business located in the southeastern United States. It offers hand‐knitted scarves; handmade hair accessories; handcrafted beaded jewelry such as necklaces, bracelets, and earrings; small handmade children's toys; and stock and custom‐printed T‐shirts. It began operations in early 2014. The owners established an online store and developed plans to sell items at local craft fairs and farmers’ markets in the southeastern United States. During its initial launch, the business generated limited orders for its products. In the beginning there was a limited amount of advertising using social media, which consisted of establishing a Facebook page, posting notifications on the business's Facebook page, and posting notifications about the business to the owners’ personal contacts on Facebook. Despite establishing a web presence and utilizing social media in its first year of operations, Suzy Q's did not generate a significant number of orders and received very little revenue. The owners of Suzy Q's, our client, established a goal to generate at least $700 per month in revenue for the calendar year 2015. Our analysis of the business revealed that the managers and employees had the skills needed to perform the work, but the lack of orders presented an obstacle to achieving their business goals. After completing a performance analysis, we recommended that Suzy Q's establish a single online presence, implement a marketing effort, establish a local presence, create a dedicated studio space, and create a formal business plan. It was our belief that Suzy Q's had the potential to reach its goals set for 2015 and beyond if these solutions were implemented. 相似文献
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Understanding the role of shaft stiffness in the golf swing 总被引:3,自引:3,他引:0
Theoretically, shaft stiffness can alter shot distance by increasing clubhead speed or altering clubhead orientation at impact.
A 3D forward dynamics model of a golfer and flexible club simulated the downswing. A genetic algorithm optimized the coordination
of the model’s muscles (four torque generators) to maximize clubhead speed. The maximum torque output and maximum rate of
torque development from the torque generators were varied to simulate the swing of golfers that generate different clubhead
speeds. Four shafts of varying stiffness (flexible, regular, stiff, and completely rigid) were entered into these simulations
to examine the role that shaft flexibility had on clubhead speed and orientation at impact. Shaft stiffness was found to have
a meaningful effect only on clubhead orientation (dynamic loft and dynamic close) at impact. There was no evidence to support
the premise that matching the stiffness properties of the shaft with the golfer would improve clubhead speed. 相似文献
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Po-Lin Pan Shuhua Zhou Marceline Thompson Hayes 《Journal of International and Intercultural Communication》2017,10(3):219-236
This study found that mortality salience in TV news activated more hostile attitude toward the perpetrators and negative judgment on the immigration issue. Social group difference influenced news viewers’ immigration issue judgment, but did not affect their resultant hostility and perceived vulnerability. More negative attitudes emerged toward the immigration issue when immigrant perpetrators were portrayed negatively in the news. News viewers with exposure to mortality salience in TV news reported more negative toward immigrants. Exposure to mortality-related elements in TV news could lead to social conflicts that were viewed as a severe threat by U.S. government and policymakers. 相似文献