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71.
This study defines the academic library as an innovation intermediary that under the service-dominant logic perspective has a role of co-creator of value instead of a traditional service provider focused on collecting and exchanging knowledge. Innovation intermediaries develop a number of roles and functions to stimulate knowledge creation and transfer by supporting interactions and collaborations among multiple parties. As result, 2×2 Matrix was created to position each library's service based on its unique combination of necessary innovation roles and functions. A single case study focused on a university library and highlighted the existence of two different types of intermediaries: generalist and specialist. 相似文献
72.
Luca Soldaini Andrew Yates Elad Yom-Tov Ophir Frieder Nazli Goharian 《Information Retrieval》2016,19(1-2):149-173
The majority of Internet users search for medical information online; however, many do not have an adequate medical vocabulary. Users might have difficulties finding the most authoritative and useful information because they are unfamiliar with the appropriate medical expressions describing their condition; consequently, they are unable to adequately satisfy their information need. We investigate the utility of bridging the gap between layperson and expert vocabularies; our approach adds the most appropriate expert expression to queries submitted by users, a task we call query clarification. We evaluated the impact of query clarification. Using three different synonym mappings and conducting two task-based retrieval studies, users were asked to answer medically-related questions using interleaved results from a major search engine. Our results show that the proposed system was preferred by users and helped them answer medical concerns correctly more often, with up to a 7 % increase in correct answers over an unmodified query. Finally, we introduce a supervised classifier to select the most appropriate synonym mapping for each query, which further increased the fraction of correct answers (12 %). 相似文献
73.
Digital skills are increasingly important for labour market outcomes and social participation. Do they also matter for academic performance? This paper investigates the effects of digital literacy on educational outcomes by merging data from the Italian National Assessment in secondary schools with an original data-set on performance tests of Internet skills for tenth-grade students. Our identification strategy relies on a rich set of individual, family, school and classroom control variables that are not commonly available in previous studies. The findings indicate that, overall, Internet skills have a positive impact on academic achievement. This effect is stronger for students with low academic performance or low family background. It is also stronger for students in technical or vocational schools. 相似文献
74.
Lisa Dragoset Jaime Thomas Mariesa Herrmann John Deke Susanne James-Burdumy Dara Lee Luca 《Journal of research on educational effectiveness》2019,12(2):215-250
As part of the American Recovery and Reinvestment Act of 2009, the School Improvement Grants (SIG) program received more than $3 billion with the goal of substantially improving student achievement. The SIG program’s funding was to help states turn around the nation’s persistently lowest-achieving schools using one of four school intervention models—transformation, turnaround, restart, or closure. We used a regression discontinuity design and a large sample of schools from more than 20 states to evaluate the impact of implementing a SIG-funded intervention model on use of SIG-promoted practices and student outcomes. Our regression discontinuity design exploited cutoff values on the continuous variables used to define the SIG eligibility tiers to compare outcomes in schools that just met the eligibility cutoff for receiving SIG funding to outcomes in schools that just missed it. We found that SIG had no impact on any of the outcomes we examined, including math and reading test scores, high school graduation rates, and college enrollment rates. Using a correlational analysis, we found the turnaround model was associated with larger student achievement gains in math than the transformation model for grades 6 through 12. 相似文献
75.
In this paper, we analyze empirically the relation between the growth of new technology-based firms and the human capital of founders, with the aim of teasing out the “wealth” and “capability” effects of human capital. For this purpose, we take advantage of a new data set relating to a sample composed of 506 Italian young firms that operate in high-tech industries in both manufacturing and services. In accordance with competence-based theories, the econometric estimates show that the nature of the education and of the prior work experience of founders exerts a key influence on growth. In fact, founders’ years of university education in economic and managerial fields and to a lesser extent in scientific and technical fields positively affect growth while education in other fields does not. Similarly prior work experience in the same industry of the new firm is positively associated with growth while prior work experience in other industries is not. Furthermore, it is the technical work experience of founders as opposed to their commercial work experience that determines growth. The fact that within the founding team there are individuals with prior entrepreneurial experiences also results in superior growth. Lastly, we provide evidence that there are synergistic gains from the combination of the complementary capabilities of founders relating to (i) economic-managerial and scientific-technical education and (ii) technical and commercial industry-specific work experiences. We conclude that the human capital of founders of new technology-based firms is not just a proxy for personal wealth. 相似文献
76.
Luca Cavanini Gionata Cimini Gianluca Ippoliti 《Journal of The Franklin Institute》2019,356(4):2015-2030
Current Mode Control (CMC) is the standard approach to regulate DC-DC power converters in high performance applications, allowing to obtain a faster time-response and better closed-loop stability if compared to Voltage Mode Control (VMC). In the last decade, several algorithms have been proposed to improve standard CMC, most of them requiring to replace the original controller. However, it is common to have either analog or embedded CMC controllers which cannot be replaced easily in commercial power converters. Inspired by very recent results in the topic, this paper proposes a Model Predictive Control (MPC) external loop aimed at optimally modifying the set-point of a CMC loop to improve converter performance. The proposed configuration is directly applicable to any pre-compensated converter as it does not require changes on the already-in-place controller. Moreover, by leveraging a multi-rate implementation, the benefits of MPC are introduced in power conversion without affecting much the computational cost of the over-all control system, contrary to what would happen for a direct MPC implementation. Simulation and experimental results on a synchronous DC-DC buck converter, controlled by a standard CMC algorithm, confirm the benefits of the approach. 相似文献
77.
Gennaro Boccia Davide Dardanello Cantor Tarperi Luca Festa Antonio La Torre Barbara Pellegrini 《European Journal of Sport Science》2018,18(5):695-704
Women are known to be less fatigable than men in single-joint exercises, but fatigue induced by running has not been well understood. Here we investigated sex differences in central and peripheral fatigue and in rate of force development (RFD) in the knee extensors after a half-marathon run. Ten male and eight female amateur runners (aged 25–50 years) were evaluated before and immediately after a half-marathon race. Knee extensors forces were obtained under voluntary and electrically evoked isometric contractions. Maximal voluntary isometric contraction (MVC) force and peak RFD were recorded. Electrically doublet stimuli were delivered during the MVC and at rest to calculate the level of voluntary activation and the resting doublet twitch. After the race, decreases in MVC force (males: ?11%, effect size [ES] 0.52; females: ?11% ES 0.33), voluntary activation (males: ?6%, ES 0.87; females: ?4%, ES 0.72), and resting doublet twitch (males: ?6%, ES 0.34; females: ?8%, ES 0.30) were found to be similar between males and females. The decrease in peak RFD was found to be similar between males and females (males: ?14%, ES 0.43; females: ?15%, ES 0.14). Half-marathon run induced both central and peripheral fatigue, without any difference between men and women. The maximal and explosive strength loss was found similar between sexes. Together, these findings do not support the need of sex-specific training interventions to increase the tolerance to neuromuscular fatigue in half-marathoners. 相似文献
78.
The paper considers a class of neural networks where flux-controlled dynamic memristors are used in the neurons and finite concentrated delays are accounted for in the interconnections. Goal of the paper is to thoroughly analyze the nonlinear dynamics both in the flux-charge domain and in the current-voltage domain. In particular, a condition that is expressed in the form of a linear matrix inequality, and involves the interconnection matrix, the delayed interconnection matrix, and the memristor nonlinearity, is given ensuring that in the flux-charge domain the networks possess a unique globally exponentially stable equilibrium point. The same condition is shown to ensure exponential convergence of each trajectory toward an equilibrium point in the voltage-current domain. Moreover, when a steady state is reached, all voltages, currents and power in the networks vanish, while the memristors act as nonvolatile memories keeping the result of computation, i.e., the asymptotic values of fluxes. Differences with existing results on stability of other classes of delayed memristor neural networks, and potential advantages over traditional neural networks operating in the typical voltage-current domain, are discussed. 相似文献
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