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591.
Alberto Téllez-Valero Manuel Montes-y-Gómez Luis Villaseñor-Pineda Anselmo Peñas Padilla 《Information processing & management》2011
Question answering (QA) is the task of automatically answering a question posed in natural language. Currently, there exists several QA approaches, and, according to recent evaluation results, most of them are complementary. That is, different systems are relevant for different kinds of questions. Somehow, this fact indicates that a pertinent combination of various systems should allow to improve the individual results. This paper focuses on this problem, namely, the selection of the correct answer from a given set of responses corresponding to different QA systems. In particular, it proposes a supervised multi-stream approach that decides about the correctness of answers based on a set of features that describe: (i) the compatibility between question and answer types, (ii) the redundancy of answers across streams, as well as (iii) the overlap and non-overlap information between the question–answer pair and the support text. Experimental results are encouraging; evaluated over a set of 190 questions in Spanish and using answers from 17 different QA systems, our multi-stream QA approach could reach an estimated QA performance of 0.74, significantly outperforming the estimated performance from the best individual system (0.53) as well as the result from best traditional multi-stream QA approach (0.60). 相似文献
592.
593.
When studying museum visitors, researchers sometimes collect data by video‐ and audio‐taping large high‐traffic areas. In order to inform visitors that they are being recorded, researchers post signs in the area. This article describes the Exploratorium's efforts to design and test trilingual signs that would effectively inform visitors when video‐based research is in progress. Interviews with 255 adult museum visitors, conducted across six versions of the recording area's setup and signage, revealed several effective design elements. The posted sign was more noticeable and welcoming when it included a large headline, a realistic camera icon, and a colorful background. The most effective setup of the area contained many cues to videotaping beyond the large posted sign, such as visible recording equipment and small signs on exhibits and cordons. In the most successful trilingual setup we tested, 92% of visitors leaving the research area knew they had been videotaped. 相似文献
594.
This paper describes the experience gained in the Center for Technological Innovation since its creation three years ago within the National Autonomous University of Mexico. By offering the services of locating clients, drafting and negotiating contracts, providing specialized information services, and project follow-up, the Center pursues the establishment of effective ties between University projects and industrial production. In so doing, its staff informally assumes the critical “dgate-keeper” and “entrepreneur” roles, not easily accepted in other areas of the University.The main difficulties encountered so far have been in developing interdisciplinary projects, providing due academic recognition for technological activities and extending knowledge about innovation throughout the University. On the other hand, a great advantage is the interest shown by the academic community; likewise is UNAM's stability and autonomy, structural characteristics which have stimulated the development of technically sound teams over several decades. To date, the Center has provided support services for 125 projects and has participated in establishing 44 contracts between the University and industry. 相似文献
595.
Diogo Martins Gomes Veronica McCauley 《International Journal of Science Education》2016,38(14):2259-2283
Science literacy has become socially and economically very important. European countries stress that science graduates are fundamental for economic growth. Nevertheless, there is a declining student participation in science. In response, there has been a call to change the way science is taught in schools, which focuses on inquiry methods rooted in constructivism. Universities and other organisations have responded by developing outreach programmes to improve student engagement in science. Given this context, there is a necessity for research to ascertain if this new relationship between outreach and education is worthwhile. This study examines and compares primary teachers and outreach practitioners understanding and perceptions of constructivist science pedagogy, in an effort to understand the potential of a teacher-outreach partnership. For this, qualitative and quantitative methods were employed, taking a dialectic pragmatic stance. Contradicting the recurrent view, teachers and outreach providers revealed favourable views in relation to constructivism, despite recognising barriers to its implementation. These results support a partnership between teachers and outreach practitioners and the realisation of the hybrid role of each participant. The results also reveal an important dynamic in outreach access to schools. Specifically, the outreach connected teachers acted as gatekeepers by negotiating access into their colleagues classrooms. 相似文献
596.
We investigate the relationship between patenting activity and the population size of metropolitan areas in the United States over the last two decades (1980-2001). We find a clear superlinear effect, whereby new patents are granted disproportionately in larger urban centers, thus showing increasing returns in inventing activity with respect to population size. We characterize this relation quantitatively as a power law with an exponent larger than unity. This phenomenon is commensurate with the presence of larger numbers of inventors in larger metropolitan areas, which we find follows a quantitatively similar superlinear relationship to population, while the productivity of individual inventors stays essentially constant across metropolitan areas. We also find that structural measures of the patent co-authorship network although weakly correlated to increasing rates of patenting, are not enough to explain them. Finally, we show that R&D establishments and employment in other creative professions also follow superlinear scaling relations to metropolitan population size, albeit possibly with different exponents. 相似文献
597.
Mónica Vallejo-Ruiz Antonio Fernández-Cano Manuel Torralbo Alexander Maz Luis Rico 《International Journal of Science and Mathematics Education》2008,6(2):313-327
This article offers an overview of mathematics education in Spain, analyzing the production of PhD theses over the last 30 years.
This period has been divided into four cycles that describe the evolution of Spanish research in the field of mathematics
education, together with changes in university and social politics. This paper also includes a forecast of the number of theses
that will be produced over the next 7 years, thus predicting the future progress and development of this area of research. 相似文献
598.
A.P. Ferreira Pinto 《文物保护研究》2014,59(2):79-90
The aim of this research work was to test the influence of stone properties, consolidation product, and application procedure on the potential harmfulness of consolidation on carbonate stones as assessed through the impacts on colour and water absorption kinetics. This article contributes to understanding the immediate and delayed impacts of consolidation treatments through the assessment of colour variation and modification of water absorption kinetics. The investigation was carried out on two limestones having a porosity of 10 and 27%, which were treated with three consolidating products (ethyl silicate, acrylic, and epoxy resins) using three treatment procedures: capillary absorption, brush, and full immersion. All products showed negative impacts at different degrees. We could show that their impact on a given stone depends not only on the consolidant type, but also on the treatment procedures. We demonstrated this way that the assessment of the potential harmfulness of a consolidation treatment for a specific intervention should be carried out in conditions as similar as possible to those expected to occur in practice and should never be based on extrapolations made from any other different conditions. The results also contribute to the definition of standard testing protocols in stone consolidation, privileging the application of a consolidant by direct contact capillary absorption when reproducibility is pursued, or by brushing when the potential highest impacts on colour are the target to evaluate. 相似文献
599.
Xavier Bonfill Dimelza Osorio Margarita Posso Ivan Sol Gabriel Rada Ania Torres Marcelo García Dieguez Maricela Pia‐Pozas Luisa Díaz‐García Mario Tristn Omar Gandarilla David A. Rincn‐Valenzuela Arturo Martí Ricardo Hidalgo Daniel Simancas‐Racines Luis Lpez Ricardo Correa Antonieta Rojas‐De‐Arias Csar Loza
scar Gianneo Hector Pardo 《Health information and libraries journal》2015,32(4):276-286
600.
Ezequiel M. Gonçalves Catarina N. Matias Diana A. Santos Luis B. Sardinha Analiza M. Silva 《Journal of sports sciences》2015,33(6):634-640
Bioelectrical impedance spectroscopy (BIS) is an inexpensive and non-invasive technique to measure total body water (TBW), extracellular water (ECW), and intracellular water (ICW). The purpose of this study was to validate TBW, ECW and ICW assessed by BIS, using dilution techniques as the reference method (REF) in elite judo athletes. Thirty-two Portuguese elite male judo athletes were evaluated during a period of weight stability. TBW, ECW and ICW were assessed by BIS (Xitron 4000). Deuterium and bromide dilution techniques were used as the criterion method for measuring TBW and ECW, while ICW was calculated as the difference between the two. BIS explained 96%, 77% and 94% of the total variability from REFs for TBW, ECW and ICW, respectively. BIS also demonstrated high precision (ρ ≥ 0.88) and accuracy (Cb = 0.98), with a minimum concordance coefficient correlation of 0.87 for ECW. The mean bias demonstrated that BIS slightly overestimated the REF in 1.1 kg (2.3%), 0.3 kg (1.6%) and 0.8 kg (2.7%) for TBW, ECW and ICW, respectively. The 95% limits of agreement ranged from ?1.2 to 3.3 kg in TBW, from ?1.8 to 2.4 kg in ECW and from ?1.0 to 2.6 kg in ICW. A non-significant trend was found between the difference and the mean of reference and alternative methods. These findings highlight the efficacy of BIS as a valid non-biased tool for the assessment of TBW and its compartments in elite male judo athletes, during a period of weight stability. 相似文献