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991.
Even when innovators know they are working with a potential breakthrough innovation, they face formidable difficulties in assessing the exact ways it will be innovative as well as deviant in regard to extant systems, business and practices. This finding emerges from our case study that spans the 40-year history of an ongoing and by now potentially radical innovation in automated and miniaturized liquid processing. We analyze the changes in the system-to-be and its relationship to its future contexts throughout this period and show how the developers were able to reliably predict technical compatibility, the outcome, the interface points and effects towards the intended environment only some distance ahead. This ‘fog of innovation’ presents a management challenge not duly met by instruments available in innovation literature. 相似文献
992.
2010年以来,以信息化、智能化、物理、数字和生物等领域新技术融合为标志的工业革命4.0,给社会生产生活带来巨大变化和新的机遇,同时,也使人类陷入前所未有的新的伦理困境。工业革命4.0有其深刻的历史根源,西方主要学术流派对工业革命4.0带来的科技伦理风险进行了反思,并提出了有代表性的观点。在此基础上,系统梳理了全球化时代工业革命4.0的科技进步带来的伦理挑战,探讨了新时代科技与工程教育的新视角、新观点与新方法。 相似文献
993.
This paper presents a North-South technology gap model which combines the Schumpeterian approach to technical and structural change with the Keynesian perspective on effective demand and the Balance-of-Payments (BOP) constraint as drivers of growth. Three are the contributions of the paper. First, it develops a model in which the technology gap, relative productivity and relative wages co-evolve and may generate different paths of convergence or divergence between South and North depending on the parameters of the model. Second, the parameters of the model are associated with different types of policies, which allows for discussing how these policies may change the growth path. Finally, the model is used to discuss the contrasting experiences of Asia and Latin America since 1970. Convergence in Asia and divergence in Latin America have been extensively debated topics in the literature on comparative economic development, which highlights the crucial role of industrial policy. It is argued that the results of the technology gap model are consistent with the findings of this literature and helps understand the forces behind convergence and divergence. 相似文献
994.
Online platforms, from Facebook to Twitter, and from Coursera to Uber, have become deeply involved in a wide range of public activities, including journalism, civic engagement, education, and transport. As such, they have started to play a vital role in the realization of important public values and policy objectives associated with these activities. Based on insights from theories about risk sharing and the problem of many hands, this article develops a conceptual framework for the governance of the public role of platforms, and elaborates on the concept of cooperative responsibility for the realization of critical public policy objectives in Europe. It argues that the realization of public values in platform-based public activities cannot be adequately achieved by allocating responsibility to one central actor (as is currently common practice), but should be the result of dynamic interaction between platforms, users, and public institutions. 相似文献
995.
Flávio R. M. Pavan Magno T. M. Silva Maria D. Miranda 《Journal of The Franklin Institute》2018,355(1):596-624
In this paper, we propose a numerically robust blind equalization scheme to mitigate cochannel and intersymbol interferences and separate signals from a convolutive mixture in multiple-input multiple-output (MIMO) communication systems. The robustness of the proposed scheme is achieved through a particular dual-mode operation applied to a constant-modulus-based space-time algorithm that corrects phase rotations. In the first mode of operation, the consistency in the nonlinear estimates of the transmitted signals is ensured. In the second mode, the Euclidean norms of the equalizer coefficient vectors decrease along the iterations, which allows the algorithm to return to the first mode of operation, where the estimation of the transmitted signals really occurs. In particular, we apply this scheme to a multimodulus version of the multiuser Shalvi-Weinstein algorithm (MU-SWA). By means of a deterministic stability analysis assuming the persistence of excitation condition, we show that the dual-mode MU-SWA does not diverge. 相似文献
996.
Maria Inez Angela Z. Ponce de Leon 《Sport in Society》2018,21(9):1302-1318
Football might not be as popular as basketball in the Philippines, but it has a loyal following. In 2012, broadcaster Arnold Clavio claimed that members of the Men’s National Team, the Azkals, were not true Filipinos. Most of the Azkals are children of Filipinos and foreign nationals, and spent their childhood abroad. Clavio’s statement prompted an online writing storm, which the researcher analyzed to examine how Filipinos constructed their identity. Analysis showed that Azkals supporters constructed the Filipino as a ‘citizen of the world’, with a dynamic identity defined by individual emotions. Clavio supporters tended to construct the Filipino as a ‘citizen of the country only’, with an identity fixed by location and acted out in culture. The debate centred on whether Filipino identity could be inherited but changed, or was fixed and immutable. These struggles raise interesting questions on national identity and unity, whether or not football is involved. 相似文献
997.
Maria Stella Valle Luciano Lombardo Matteo Cioni 《European Journal of Sport Science》2018,18(9):1217-1225
Learning precision ball throwing was mostly studied to explore the early rapid improvement of accuracy, with poor attention on possible adaptive processes occurring later when the rate of improvement is reduced. Here, we tried to demonstrate that the strategy to select angle, speed and height at ball release can be managed during the learning periods following the performance stabilization. To this aim, we used a multivariate linear model with angle, speed and height as predictors of changes in accuracy. Participants performed underarm throws of a tennis ball to hit a target on the floor, 3.42 m away. Two training sessions (S1, S2) and one retention test were executed. Performance accuracy increased over the S1 and stabilized during the S2, with a rate of changes along the throwing axis slower than along the orthogonal axis. However, both the axes contributed to the performance changes over the learning and consolidation time. A stable relationship between the accuracy and the release parameters was observed only during S2, with a good fraction of the performance variance explained by the combination of speed and height. All the variations were maintained during the retention test. Overall, accuracy improvements and reduction in throwing complexity at the ball release followed separate timing over the course of learning and consolidation. 相似文献
998.
This study examined how children’s physical activity levels during recess and lunchtime and the contribution of recess and lunchtime to daily physical activity differed across seasons. Three hundred and twenty-six children aged 8–11 years from Australia participated. Physical activity was measured every 15-seconds using hip-mounted ActiGraph accelerometers for 7 consecutive days during the winter (n = 246), spring (n = 211), summer (n = 161) and autumn terms (n = 139). Data were collected 2012–2013. Time spent in light- (LPA) moderate- (MPA), vigorous- (VPA), and moderate- to vigorous-intensity physical activity (MVPA) during recess and lunchtime were calculated. Longitudinal data were analysed using multilevel analyses and adjusted for potential confounders. The results showed that compared to winter, children engaged in significantly less MVPA and VPA in spring and summer during lunchtime (p < 0.05). No significant changes were observed during recess. The contribution of lunchtime to VPA and MVPA significantly decreased in spring and summer compared to winter (p < 0.05). Children’s lunchtime physical activity levels decreased between winter and spring and summer, with greater declines observed in VPA. Strategies to increase physical activity levels in every season are needed during lunchtime, with a greater emphasis on warmer months. 相似文献
999.
Achievement goal theory provides a framework to help understand how individuals behave in achievement contexts, such as sport. Evidence concerning the role of motivation in the decision to use banned performance enhancing substances (i.e., doping) is equivocal on this issue. The extant literature shows that dispositional goal orientation has been weakly and inconsistently associated with doping intention and use. It is possible that goal involvement, which describes the situational motivational state, is a stronger determinant of doping intention. Accordingly, the current study used an experimental design to examine the effects of goal involvement, manipulated using direct instructions and reflective writing, on doping likelihood in hypothetical situations in college athletes. The ego-involving goal increased doping likelihood compared to no goal and a task-involving goal. The present findings provide the first evidence that ego involvement can sway the decision to use doping to improve athletic performance. 相似文献
1000.
Dominique Silva Silveira Luis Filipe Gomes Barbosa Ferreira Lemos Rafael Miranda Tassitano Maria Teresa Cattuzzo Anderson Henry Pereira Feitoza Luisa Maria Seara Moreira Carneiro Aires 《Journal of sports sciences》2018,36(20):2317-2326
This study evaluated the effect of a multi-component intervention on motor performance (MP) and metabolic risk markers (MRM) in overweight/obese youth. A secondary aim was to examine whether changes in MP are associated to changes in MRM. A 3-month multi-component intervention was performed, consisting of physical exercise sessions (twice/week;1h), nutritional education sessions (once/month), and parental support (twice/week). The sample included 35 volunteers (7–13 y.o), allocated to intervention (INT, n = 17) and control (CONT, n = 18) group. Variables were measured pre (T0) and post intervention (T1). Fasting blood samples were analyzed for MRM. MP tests included the measurement of health related physical fitness components and motor coordination performance (KTK battery). To assess food intake, a 24-hour recall diary was used. GLM-ANCOVA was performed. Standardized scores were calculated for the outcome variables, and multilinear regressions were applied to analyze associations between the key variables. INT group showed improvements in MP, glycolytic and hepatic profiles. After adjustments for MVPA, SB, total intake and maturational stage, negative associations between %ΔMP and %Δglycolytic (β = -.424; 95%CI:-0.343:-0.022), and %Δhepatic scores (β = -.382 95%CI:-0.001:-0.009) were observed. The intervention produced a moderate-to-high effect on the MP and some MRM. Changes in MP were inversely associated with changes in glycolytic and hepatic markers. 相似文献