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901.
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
902.
903.
H. Sadjadi 《Journal of The Franklin Institute》2011,348(1):112-124
This paper outlines the development of a robotic system designed to clean the outer surface of elliptic tapered structures such as Dubai airport concourse. The designed system consists of two identical cleaning satellites connected to a main unit and provides cleaning coverage up to 83° tilt from the horizontal surface of the concourse. The controller design, sensors, localization, and employed communication techniques are presented in this paper along with the final results of the implemented prototype. The system features redundant locomotion to ensure safe and reliable operation while maintaining autonomy and flexibility. 相似文献
904.
Wouter P.C. BoonAuthor Vitae Ellen H.M. Moors Author VitaeStefan Kuhlmann Author Vitae Ruud E.H.M. Smits Author Vitae 《Research Policy》2011,40(2):242-252
User involvement is assumed to be beneficial to innovation processes. Intermediary user organisations contribute to articulating societal demands for innovations. However, the learning processes inside these organisations are still not understood well. Therefore, this paper empirically investigates intermediaries using an event history approach. It yields characteristic learning mechanisms, e.g. concerning the management of expectations or actively building a case. If intermediaries overcome challenges regarding positioning, representation and the level of proactivity, they can play a precarious role in demand articulation in the context of new technologies. 相似文献
905.
The present study was aimed at investigating the relationships between autonomy-connectedness and adherence to independent and interdependent values in second-generation Dutch immigrant women with a background in countries labeled as collectivistic, and same-aged indigenous Dutch women (N = 180 and N = 157, respectively). Both groups completed the Autonomy-Connectedness Scale (ACS-30; Bekker & Van Assen, 2006) and the Self-Construal Scale (Singelis, 1994). Additionally, those with an immigrant background filled out the Acculturation Questionnaire (Arends-Tóth & Van de Vijver, 2003). Contrary to expectations, both groups had similar levels of self-awareness, whereas the indigenous Dutch women were - after controlling for educational level - more sensitive to others. In both groups, but even more in the group with an immigrant background, adherence to independent values appeared to contribute substantially and positively to self-awareness as well as capacity for managing new situations, and negatively to sensitivity to others. In addition, adherence to interdependent values contributed, for both groups, positively to sensitivity to others, and, for those with an immigrant background, negatively to self-awareness. The ACS-30 appeared to be useful for assessing autonomy-connectedness in the immigrant groups that participated in the study. The results confirm that a simple distinction between native and immigrant Dutch groups in terms of being self- or other-focused should be rejected, and give rise to further, clinically relevant research questions. 相似文献
906.
Although triathlon is growing in popularity at a remarkable rate, it has not been extensively studied. The aims of this research were to identify preparation strategies used by triathletes and to categorize these strategies according to gender and consultation with triathlon coaches. Survey data collected from 401 triathletes (207 males, 194 females) revealed training, nutritional, and mental preparation habits. Most participants engaged in strength training, consumed food and/or fluids during and after training, set training and competition goals, and applied mental preparation strategies during training and the hour before racing. Water was the most commonly consumed fluid; positive self-talk was the most used mental strategy. Participants were more likely to consult with a triathlon coach than a nutrition or sport psychology professional. Athletes with more years of experience in triathlon and those competing in longer distances were more likely to consult a triathlon coach. Female triathletes were more likely than male triathletes to train with others, use mental preparation strategies, and report feeling anxious before competitions. More male triathletes reported using nutritional supplements during training than their female counterparts. These findings add to the limited research base on triathletes' training habits, and hopefully will help guide practitioners who work with this group. The results provide guidance for collaborative efforts among training, nutrition, and mental health professionals to best support triathletes. 相似文献
907.
Koning RH 《Journal of sports sciences》2011,29(1):19-27
Home advantage is a pervasive phenomenon in sport. It has been established in team sports such as basketball, baseball, American football, and European soccer. Attention to home advantage in individual sports has so far been limited. The aim of this study was to examine home advantage in professional tennis. Match-level data are used to measure home advantage. The test used is based on logit models, and consistent specification is addressed explicitly. Depending on the interpretation of home advantage, restrictions on the specification of the model need to be imposed. We find that although significant home advantage exists for men, the performance of women tennis players appears to be unaffected by home advantage. 相似文献
908.
909.
Effect of hand paddles and parachute on the index of coordination of competitive crawl-strokers 总被引:1,自引:1,他引:0
We investigated the effects of hand paddles and parachute on the relative duration of stroke phases and index of coordination of competitive crawl-strokers. Eleven male-swimmers (age: 21.9 ± 4.5 years; 50-m best time: 24.23 ± 0.75 s) were evaluated in four maximal-intensity conditions: without equipment, with hand paddles, with parachute, and with both hand paddles and parachute. Relative stroke phase duration of each arm, swimming velocity, and stroke rate were analysed from video (60 Hz). The index of coordination was quantified based on the lag time between propulsive phases of each arm, which defined the coordination mode as catch-up, opposition or superposition. The stroke rate decreased in all conditions (P < 0.05) and swimming velocity decreased with parachute and with paddles + parachutes (P < 0.05). The coordination mode changed from catch-up in free swimming (-2.3 ± 5.0%) to opposition with paddles (-0.2 ± 3.8%), parachute (0.1 ± 3.1%), and paddles + parachute (0.0 ± 3.2%). Despite these variations, no significant differences were observed in relative duration of right and left arm-stroke phases, or in index of coordination. We conclude that the external resistances analysed do not significantly influence stroke phase organization, but, as a chronic effect, may lead to greater propulsive continuity. 相似文献
910.
We assessed how golfers cope with the commonly observed systematic overshoot errors in the perception of the direction between the ball and the hole. Experiments 1 and 2, in which participants were required to rotate a pointer such that it pointed to the center of the hole, showed that errors in perceived direction (in degrees of deviation from the perfect aiming line) are destroyed when the head is constrained to move within a plane perpendicular to the green. Experiment 3 compared the errors in perceived direction and putting errors of novice and skilled players. Unlike the perceived direction, putting accuracy (in degrees of deviation from the perfect aiming line) was not affected by head position. Novices did show a rightward putting error, while skilled players did not. We argue that the skill-related differences in putting accuracy reflect a process of recalibration. Implications for aiming in golf are discussed. 相似文献