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151.
Mario?PascalevEmail authorView authors OrcID profile 《Ethics and Information Technology》2017,19(1):39-48
This article reviews the qualitative changes that big data technology introduced to society, particularly changes that affect how individuals control the access, use and retention of their personal data. In particular interest is whether the practice of privacy self-management in this new context could still ensure the informed consent of individuals to the privacy terms of big data companies. It is concluded that that accepting big data companies’ privacy policies falls short of the disclosure and understanding requirements for informed consent. The article argues that the practice of privacy self-management could remain viable if the review, understanding and acceptance of privacy agreements is streamlined, standardized and automated. Technology should be employed to counter the privacy problems created by big data technology. The creation of the privacy exchange authorities (PEA) is proposed as a solution to the failures of privacy self-management. The PEA are intermediaries that empower individuals to define their own privacy terms and express informed consent in their dealings with data companies. They will create the technological infrastructure for individuals to select their own privacy terms from a list of standard choices, potentially only once. The PEA will further mediate the delivery and authentication of the individual users’ privacy terms to data companies. A logical proof of concept is offered, illustrating the potential steps involved in the creation of the PEA. 相似文献
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Seong Hwan Oh Andreas Mierau Mario Thevis Andreas Thomas Christoph Schneider Alexander Ferrauti 《Sportwissenschaft》2018,48(2):235-244
The aim of this study was to investigate the effect of two different exercise interventions in the morning on football-specific components of performance in the afternoon under conditions simulating a competition day. In the morning on 3 experimental days, 12 football players (age 24.1?±?5.5 years) completed three different preload interventions that were applied in a counter-balanced order: (1) no intervention (NI); (2) moderate-intensive exercise (MI); and (3) high-intensive exercise (HI). The subjects performed the preload exercises, consisting of a small-sided game and repeated maximal sprints, from 10:00–11:00 a.m. At 3:00 p.m., the Bangsbo test (BT) was applied to examine the effects of the different morning interventions on football-specific endurance capacity. The results showed that the HI led to significantly higher blood-lactate concentrations (moderate to very large effect) and heart rates (very large to extremely large effect) compared to the MI. In addition, there was a significant measurement?×?intervention effect on concentrations of adrenalin and noradrenalin in the urine, which reached higher values immediately after the HI (very large effect) and MI (moderate effect) compared to NI. All effects disappeared by the time of the BT in the afternoon. During all trials, after the preload intervention, reaction time and critical flicker fusion frequency increased significantly compared to the baseline morning values (reaction time: small; critical flicker fusion: trivial to small effect), but no measurement?×?intervention interaction was found. During the BT, the mean total distance covered (trivial to small effect) and the pacing pattern did not differ significantly among the trials despite numerous small individual effects. We conclude that exercise interventions of various intensities in the morning have no general effect on football-specific components of performance in the afternoon despite significant metabolic, endocrinological and cognitive short-term effects. Coaches should consider individual preferences when prescribing competition-day procedures. 相似文献
154.
Luigi Gabrielli Marta Sitges Mario Chiong Jorge Jalil María Ocaranza Silvana Llevaneras 《European Journal of Sport Science》2018,18(9):1288-1297
Moderate endurance exercise has long been considered an essential element to maintain cardiovascular health, and sedentary behaviour in the general population has been related to a significant increase in all-causes of mortality, cardiovascular disease mortality and cardiovascular disease incidence. However, a growing group of people performs an intense exercise that leads to multiple heart adaptive changes that are collectively called “athlete’s heart”. In this review, we discussed the evidence of cardiac remodelling process secondary to repetitive and strenuous exercise in some predisposed athletes that produces intense and probably deleterious changes in cardiac morphology and function with no clear clinical significance in long-term follow-up. Moreover, we also discussed the individual biological response to exercise assessed by myocardial damage, inflammation, oxidative stress, fibrosis and ventricular hypertrophy biomarkers showing different intensities with equivalent exertion. 相似文献
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Mario Porru Alessandro Serpi Ignazio Marongiu Alfonso Damiano 《Journal of The Franklin Institute》2018,355(2):728-752
Two different control approaches for suppressing DC-link voltage unbalance in Three-Level Neutral-Point Clamped Converters (NPCs) are presented in this paper. They both guarantee DC-link voltage equalization over any NPC operating conditions, i.e. when the NPC feeds or is supplied by the main AC grid at different active and/or reactive power rates. The proposed control approaches consist of either a hysteresis or a proportional regulator, each of which synthesizes the most suitable control action based on the actual DC-link voltage unbalance. Particularly, two different PWM techniques have been developed in order to achieve DC-link voltage equalization successfully, preserving NPC voltage and current waveforms at the same time. The performances achievable by means of both the proposed control approaches have been compared to each other through an extensive simulation study in order to highlight their most important advantages and drawbacks, as well as their effectiveness over any operating conditions. Particularly, both control approaches are validated in the Matlab-Simulink environment referring to DC-link voltage equalization of an NPC that represents the point of common coupling between a DC microgrid and the main AC grid. 相似文献
157.
Mario Kafouros Chengqi Wang Eva Mavroudi Junjie Hong Constantine S. Katsikeas 《Research Policy》2018,47(7):1243-1255
We examine how the ways in which firms geographically configure their global portfolios of R&D units influence the effectiveness of firms’ own R&D investments and of external technical knowledge in enhancing firm performance. Our analysis indicates that the strength of these effects depends on the extent to which firms spread their R&D units across countries (geographic dispersion of R&D) and the extent to which firms establish multiple R&D units within each country (co-location of R&D). We show that geographic dispersion and co-location are associated with distinct value creation and value capture mechanisms and in turn lead to different performance outcomes. Although geographic dispersion enhances the effects of a firm’s own R&D on its performance, R&D co-location limits such effects. These relationships are reversed when we consider the effects of external technical knowledge on firm performance. R&D co-location, rather than geographic dispersion, is what renders the exploitation of external knowledge more effective in enhancing firm performance. Our results suggest that future research should shift its focus from the degree of R&D globalization to how a portfolio is globalized and geographically structured. 相似文献
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