The World: A History,Combined Volume,by Felipe Fernández-Armesto. Upper Saddle River,NJ: Prentice Hall, 2006, 1152 pp., $126.20 hardbound.     

Ricardo Duchesne 《Academic Questions》2008,21(2):226-237

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A multilevel analysis of late entry in Nigeria     

Marcos Delprato  Ricardo Sabates 《International Journal of Research & Method in Education》2015,38(1):83-99

This paper explores how factors operating at the state and community levels are associated with the prevalence of late school enrolment in Nigeria. We investigate the following three research themes. First, whether late entry varies across states and across communities and how much of this variation can be explained by the composition of communities and states. Second, whether community wealth and state wealth are stronger predictors of late entry than household wealth. Third, whether wealth has different effects on the probability of late school entry in different states and in different communities within states. Using the 2010 Nigeria Education Data Survey, and a three-level multilevel logit model, we show that a substantial proportion of the variation in late school entry is explained by community- and state-level factors. We further find that children living in specific communities in Nigeria may face a double disadvantage in terms of on-time school enrolment. In these communities, not only is there a large proportion of children entering school late, but also household wealth has strong effects on the probability that a child is sent to school on on time. These communities could be targeted for educational interventions aimed at promoting on-time school enrolment.  相似文献   

Kinematic,kinetic and EMG analysis of four front crawl flip turn techniques     

Suzana Matheus Pereira  Caroline Ruschel  Marcel Hubert  Leandro Machado  Helio Roesler  Ricardo Jorge Fernandes 《Journal of sports sciences》2015,33(19):2006-2015

This study aimed to analyse the kinematic, kinetic and electromyographic characteristics of four front crawl flip turn technique variants. The variants distinguished from each other by differences in body position (i.e. dorsal, lateral, ventral) during rolling, wall support, pushing and gliding phases. Seventeen highly trained swimmers (17.9 ± 3.2 years old) participated in interventional sessions and performed three trials of each variant, being monitored with a 3-D video system, a force platform and an electromyography (EMG) system. Studied variables: rolling time and distance, wall support time, push-off time, peak force and horizontal impulse at wall support and push-off, centre of mass horizontal velocity at the end of the push-off, gliding time, centre of mass depth, distance, average and final velocity during gliding, total turn time and electrical activity of Gastrocnemius Medialis, Tibialis Anterior, Biceps Femoris and Vastus Lateralis muscles. Depending on the variant, total turn time ranged from 2.37 ± 0.32 to 2.43 ± 0.33 s, push-off force from 1.86 ± 0.33 to 1.92 ± 0.26 BW and centre of mass velocity during gliding from 1.78 ± 0.21 to 1.94 ± 0.22 m · s^?1. The variants were not distinguishable in terms of kinematical, kinetic and EMG parameters during the rolling, wall support, pushing and gliding phases.  相似文献   

Critical elements for product innovation at Portuguese innovative SMEs: an intellectual capital perspective     

Costa  Ricardo V  Fernández-Jardon Fernández  Carlos  Figueroa Dorrego  Pedro 《知识管理研究与实践》2014,12(3):322-338

Knowledge Management Research & Practice - The general purpose of this research is to study interaction effects between intangible assets and product innovation. More specifically, the authors...  相似文献   

Evaluating research and researchers by the journal impact factor: Is it better than coin flipping?     

Ricardo Brito  Alonso Rodríguez-Navarro 《Journal of Informetrics》2019,13(1):314-324

The journal impact factor (JIF) is the average of the number of citations of the papers published in a journal, calculated according to a specific formula; it is extensively used for the evaluation of research and researchers. The method assumes that all papers in a journal have the same scientific merit, which is measured by the JIF of the publishing journal. This implies that the number of citations measures scientific merits but the JIF does not evaluate each individual paper by its own number of citations. Therefore, in the comparative evaluation of two papers, the use of the JIF implies a risk of failure, which occurs when a paper in the journal with the lower JIF is compared to another with fewer citations in the journal with the higher JIF. To quantify this risk of failure, this study calculates the failure probabilities, taking advantage of the lognormal distribution of citations. In two journals whose JIFs are ten-fold different, the failure probability is low. However, in most cases when two papers are compared, the JIFs of the journals are not so different. Then, the failure probability can be close to 0.5, which is equivalent to evaluating by coin flipping.  相似文献   

An unsupervised heuristic-based approach for bibliographic metadata deduplication     

Eduardo N. Borges  Moisés G. de Carvalho  Renata Galante  Marcos André Gonçalves  Alberto H.F. Laender 《Information processing & management》2011

Digital libraries of scientific articles contain collections of digital objects that are usually described by bibliographic metadata records. These records can be acquired from different sources and be represented using several metadata standards. These metadata standards may be heterogeneous in both, content and structure. All of this implies that many records may be duplicated in the repository, thus affecting the quality of services, such as searching and browsing. In this article we present an approach that identifies duplicated bibliographic metadata records in an efficient and effective way. We propose similarity functions especially designed for the digital library domain and experimentally evaluate them. Our results show that the proposed functions improve the quality of metadata deduplication up to 188% compared to four different baselines. We also show that our approach achieves statistical equivalent results when compared to a state-of-the-art method for replica identification based on genetic programming, without the burden and cost of any training process.  相似文献   

Software product evolution for Intellectual Capital Management: The case of Meta4 PeopleNet     

Ricardo Colomo-PalaciosAuthor VitaeEduardo FernandesAuthor Vitae  Pedro Soto-AcostaAuthor Vitae  Marc Sabbagh^{Author Vitae} 《International Journal of Information Management》2011,31(4):395-399

Software must evolve in order to adapt to new demands and scenarios. In the case of packaged software that can be customized, this evolution implies the maintenance of both out-of-the-box and customized functionality alike. New user interface technologies provide a way to interact with applications that software vendors are forced to incorporate in order to meet new user and market requirements. Packaged software vendors are facing software evolution processes in order to attract more customers and conserve the existing ones. This case analysis describes the evolution of packaged software, Meta4 PeopleNet, towards the addiction of Rich Internet Applications features to a Human and Intellectual Capital Management tool. The findings and lessons learned presented in this case study provide useful insights for packaged software vendors facing software product evolution.  相似文献   

The rating of perceived exertion predicts intermittent vertical jump demand and performance     

Pereira G  Correia R  Ugrinowitsch C  Nakamura F  Rodacki A  Fowler N  Kokubun E 《Journal of sports sciences》2011,29(9):927-932

The aims of this study were (a) to assess the ability of the rating of perceived exertion (RPE) to predict performance (i.e. number of vertical jumps performed to a fixed jump height) of an intermittent vertical jump exercise, and (b) to determine the ability of RPE to describe the physiological demand of such exercise. Eight healthy men performed intermittent vertical jumps with rest periods of 4, 5, and 6 s until fatigue. Heart rate and RPE were recorded every five jumps throughout the sessions. The number of vertical jumps performed was also recorded. Random coefficient growth curve analysis identified relationships between the number of vertical jumps and both RPE and heart rate for which there were similar slopes. In addition, there were no differences between individual slopes and the mean slope for either RPE or heart rate. Moreover, RPE and number of jumps were highly correlated throughout all sessions (r = 0.97-0.99; P < 0.001), as were RPE and heart rate (r = 0.93-0.97; P < 0.001). The findings suggest that RPE can both predict the performance of intermittent vertical jump exercise and describe the physiological demands of such exercise.  相似文献   

Proactive interference of open field on consummatory successive negative contrast     

Nadia Justel  Ricardo Pautassi  Alba Mustaca 《Learning & behavior》2014,42(1):58-68

Reactivity to a reward is affected by prior experience with the different reinforcer values of that reward, a phenomenon known as incentive relativity, which can be studied using the consummatory succesive negative contrast (cSNC) paradigm, in which the performance of animals that receive a 4 % sucrose solution after trials on which they were exposed to 32 % sucrose is compared with that of subjects that always receive the 4 % sucrose solution. The exploration of a novel open field can enhance or block the acquisition of associative and nonassociative memories. The effect of open field on cSNC has not yet been explored. The main result of the present study was that open-field exposure significantly modified the expression of cSNC. Exposure to an open field 1 h but not immediately before the downshift interfered with the expression of cSNC. These animals drank more of the downshifted reward than did controls that were not exposed to the apparatus, and this behavior persisted for up to three recovery trials. This phenomenon was observed even when the animals were given a more protracted preshift phase and when the discrepancy between the preshift and shift incentive values of sucrose were increased. An open field also interfered with incentive downshift when open-field exposure occurred 6 h before the downshift, and repeated exposure to the apparatus did not deteriorate this effect. The present study adds to a growing body of literature that indicates that open-field exploration can interfere with memory formation.  相似文献   

Banco de ideas     

Ricardo Laviña  Narcís Vives  Xavier Avila 《Cultura y Educación》2013,25(3-4):166-172

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