排序方式: 共有125条查询结果,搜索用时 15 毫秒
61.
Diego Raphael Amancio Osvaldo Novais Oliveira Luciano da Fontoura Costa 《Journal of Informetrics》2012,6(3):427-434
Various factors are believed to govern the selection of references in citation networks, but a precise, quantitative determination of their importance has remained elusive. In this paper, we show that three factors can account for the referencing pattern of citation networks for two topics, namely “graphenes” and “complex networks”, thus allowing one to reproduce the topological features of the networks built with papers being the nodes and the edges established by citations. The most relevant factor was content similarity, while the other two – in-degree (i.e. citation counts) and age of publication – had varying importance depending on the topic studied. This dependence indicates that additional factors could play a role. Indeed, by intuition one should expect the reputation (or visibility) of authors and/or institutions to affect the referencing pattern, and this is only indirectly considered via the in-degree that should correlate with such reputation. Because information on reputation is not readily available, we simulated its effect on artificial citation networks considering two communities with distinct fitness (visibility) parameters. One community was assumed to have twice the fitness value of the other, which amounts to a double probability for a paper being cited. While the h-index for authors in the community with larger fitness evolved with time with slightly higher values than for the control network (no fitness considered), a drastic effect was noted for the community with smaller fitness. 相似文献
62.
63.
Willian M. Kuhnert Paulo J. Paupitz Gonçalves Diego F. Ledezma-Ramirez Michael J. Brennan 《Journal of The Franklin Institute》2021,358(1):1070-1086
Recently, a lot of attention has been given to a mechanical device known as the inerter. It is a mechanical component that can be compared to a capacitor with two ungrounded terminals in the mechanical-electrical systems analogy. In this paper, it is shown that although the concept of an inerter as a separate mechanical element is relatively new, there are several well-established vibration isolation systems that exhibit similar behavior to a simple lumped parameter system containing an inerter. Through a review of the literature, a link is established between the old and new ideas. Furthermore, a comparison between the systems is carried out using the quantities of mechanical impedance and displacement transmissibility. The advantages and disadvantages of using the inerter in vibration isolation are discussed, and a simple way of improving the high-frequency performance without severely degrading the low-frequency performance is described. 相似文献
64.
Luiz Antonio Joia Diego Altieri 《The Journal of High Technology Management Research》2018,29(2):204-215
E-Hailing Apps (EHA) – mobile device software to order any form of transportation pick up – have become very popular in society due to the swift proliferation of smartphones worldwide. Thus, the scope of this article is to ascertain the antecedents of continued use intention of EHA from the passengers' standpoint. To achieve this, a meta-model was developed via a theoretical background based on theories of information system adoption, diffusion of innovation, trust in virtual environments and user satisfaction, as well as research hypotheses. By applying structural equation modelling in data collected via a web survey, the theoretical meta-model and research hypotheses were tested. It was established that perceived utility, compatibility, relative advantage and trust are antecedents of user satisfaction with EHA, this factor being an antecedent of the continued use intention of same. Lastly, it was found that subjective norms have a direct and statistically significant impact on the continued use intention of EHA. 相似文献
65.
Irene M. Loe Maria D. Balestrino Randall A. Phelps Marcia Kurs‐Lasky Diego Chaves‐Gnecco Jack L. Paradise Heidi M. Feldman 《Child development》2008,79(6):1853-1868
In a prospective study of developmental outcomes in relation to early‐life otitis media, behavioral, cognitive, and language measures were administered to a large, diverse sample of children at 2, 3, 4, 6, and 9–11 years of age (N = 741). At 9–11 years of age, 9% of the children were categorized as having attention‐deficit/hyperactivity disorder (ADHD) based on parent report. Compared to the non‐ADHD group, the ADHD group had higher (i.e., less favorable) scores on parent and teacher versions of the Child Behavior Checklist at all ages. Children in the ADHD group also had lower scores on cognitive and receptive language measures in preschool. The findings support the concept that ADHD is a cognitive as well as a behavioral disorder. 相似文献
66.
Alicia Perdigones Diego Luis Valera Guillermo Pedro Moreda Jose Luis García 《European Journal of Engineering Education》2014,39(5):527-538
The Rural Engineering Department (Technical University of Madrid) ran three competence surveys during the 2006–2007 and 2007–2008 academic years and evaluated: (1) the competences gained by agricultural engineer's degree and agricultural technical engineer's degree students (360 respondents); (2) the competences demanded by agricultural employers (50 farming sector employers); (3) competences required by farming sector professionals and former students (70 professionals). The surveys show significant differences between what competences agricultural employers require of graduates and the competences they acquire during their agricultural engineering degree courses. Recruiters are looking for generic competences such as the ability to coordinate groups and place less importance on knowledge of engineering, biology, applied economics and legislation. Of the computer-related competences, those most in demand by sector professionals were related to the use of Microsoft Office/Excel (used by 79% of professionals). Surveys were used to redesign some subjects of the degrees. 相似文献
67.
68.
Iñaki Etaio Itziar Churruca Diego Rada Jonatan Miranda Amaia Saracibar Fernando Sarrionandia 《Interactive Learning Environments》2018,26(2):175-188
European Frame for Higher Education has led universities to adapt their teaching schemes. Degrees must train students in competences including specific and cross-curricular skills. Nevertheless, there are important limitations to follow skill improvement through the consecutive academic years. Final-year dissertation (FYD) offers the opportunity to assess these aspects so linked to the professional requirements. The experience reported here offers an alternative methodology for the FYD in order to reinforce cross-curricular skills and substitute the classic final evaluation schemes. A new protocol for the FYD was defined and tested in the Degree in Human Nutrition and Dietetics, with the participation of students and lecturers from different disciplines. The new methodology included collaborative activities that required students active implication and participation. New cross-curricular skills not considered before were included and evaluated in a continuous way: analysis and critical attitude, as well as team working. Obtained data revealed an improvement over cross-curricular skills. Student–student cooperation resulted in significant contributions to enhance FYD quality. The new methodology was satisfactorily valued by students. The main keys for the successful implementation of this protocol were the followings: encouragement of teachers and students, coordination, information and communication technologies, and clear guidelines. 相似文献
69.
Josefa León-López Carmen Calderón-Soto Matías Pérez-Sánchez Belén Feriche Xavier Iglesias Diego Chaverri 《European Journal of Sport Science》2018,18(6):832-841
Using a controlled parallel group longitudinal trial design, we investigated the effects of different training interventions on the prooxidant/antioxidant status of elite athletes: living and training at moderate altitude for 3 (Hi-Hi3) and 4 weeks (Hi-Hi), and for 4 weeks too, living high and training high and low (Hi-HiLo) and living and training at sea level (Lo-Lo). From 61 swimmers, 54 completed the study. Nitrites, carbonyls, and lipid peroxidation (LPO) levels were assessed in plasma. Enzymatic antioxidants glutathione peroxidase (GPx) and glutathione reductase (GRd), and non-enzymatic antioxidants total glutathione (GST), reduced glutathione (GSH) and oxidized glutathione (GSSG) were analysed in the erythrocyte fraction. At the end of the intervention, nitrites levels were similar in all altitude groups but higher than in the Lo-Lo controls (P?=?.02). Hi-HiLo had greater GPx activity than Hi-Hi and Hi-Hi3 during most of the intervention (P?≤?.001). GRd activity was higher in Lo-Lo than in Hi-Hi at the end of the training camp (P?≤?.001). All groups showed increased levels of LPO, except Lo-Lo, and carbonyls at the end of the study (P?≤?.001). Training at altitude for 3 or 4 weeks drives oxidative stress leading to cellular damage mainly by worsening the antioxidant capacities. The GSSG/GSH ratio appears to be related to perceived exertion and fatigue. The stronger antioxidant defence showed by the Hi-HiLo group suggests an inverse relationship between redox alterations and performance. Further studies are required to investigate the role of oxidative stress in acclimatization, performance, and health. 相似文献
70.
Diego Boerchi Semira Tagliabue 《International Journal for Educational and Vocational Guidance》2018,18(2):181-201
The object of this study was to assess students' perceptions of their parents’ career-related behaviours and their influence on the students’ behaviours. In study 1 (528 students), we developed the SIL Scale (support, interference and lack of engagement), a nine-item questionnaire applied to educational and job contexts. In study 2 (1204 students), we tested a person-centred approach and developed a new model called the WID Types (willing, involved and in difficulty), which identifies three clusters of students. The associations between the clusters and career choice difficulties, level of career exploration and stage of the vocational choice confirmed its validity. 相似文献