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991.
The concept of industry 4.0 (i4.0) encompasses the integration of different technologies into an autonomous, knowledge- and sensor-based, self-regulating production system. Our objective is to synthesize which are the challenges and opportunities of adopting i4.0 from the perspective of technology provider companies. A single-case research was conducted with ten companies at the Portuguese Production Technologies Cluster. Based on i4.0 technologies – Augmented reality; Additive Manufacturing; Big Data; Cloud Computing; Cyber-Physical Systems; Cybersecurity; Smart Robotics; Simulation; and System Integration – interviewees mentioned that the main adoption challenges are the analysis of data generated, integration of new technologies with available equipment and workforce, and computational limitations. The main opportunities are improvements in: efficiency; flexibility; productivity; cybersecurity; quality of products and services; and decision process due to data analysis. Interviewees have also foreseen changes in company's business model through the integration of internal resources with complementary activities of their partners and other cluster companies.  相似文献   
992.
This paper explores a case of knowledge-intensive consumer services (KICS). Services have become less neglected in the economics of technical change and innovation studies in general; nevertheless, the advance of this agenda has been uneven. A significant emphasis has been on knowledge-intensive business services (KIBS). Despite their direct impact on social needs and individual desires, innovation in consumer-oriented services continues to be relatively under-theorized and under-researched. This paper brings into focus the sources and patterns of innovation in those innovative services that target human satisfaction and well-being as a final goal. We show evidence from a little-explored health industry, oral care. We address Malo Clinic, a company specialized in the most complex patient situations and a rare instance of an internationalized firm in the health services business. On the basis of a 20-year thread of corporate history, we find that a wide array of qualitative (interviews, newspaper coverage, marketing material) and quantitative evidence (papers, patents, trademarks) illuminates some of the features that may characterize a particular class of dynamic activities tending to consumers’ needs, expectations and quality of life. We argue that these key characteristics may be on course to become more general as the learning economy spreads to fully embrace the realm of the service sphere. One conclusion is that both the technological and non-technological capabilities underpinning more types of innovation are increasingly becoming coupled in consumer-relevant services.  相似文献   
993.
The main objective of this paper is to drive a rotary inverted pendulum by following a desired navigation instruction. This navigation is commanded by the user through a new electromagnetic device which is allowed to perturb the pendulum from its upright position. This apparatus consists of an electronic magnetic driving circuit to introduce commands and realized via two operated magnetic coils. So, the external programmed magnetic perturbation can be seen as external commandments. Therefore, the control problem statement is solved via a modified regulation control implementation, to maintain the pendulum on its upright position and giving free manipulation of the base of the rotary inverted pendulum. Hence, by using the corresponding H-linear matrix inequality technique, a static state controller is designed and tested experimentally so supporting our findings.  相似文献   
994.
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   
995.
This study aimed to validate an English version of Basic Psychological Needs Support Questionnaire (BPNSQ) and the Basic Psychological Needs in Physical Education Scale (BPN-PE) in the physical education context. Participants included 453 students aged between 12 and 17 years. For the BPNSQ, the hypothesized three-factor solution displayed high interfactor correlations (rs > 1), and a follow-up analysis indicated that the items were represented by a single need-support factor. For the BPN-PE, hypothesized three-factor solution was supported. Both scales were found invariant across gender, and the nomological validity was also demonstrated through the associations between factors of both scales. This study provides initial support for the use of the BPN-PE to assess psychological need satisfaction within the physical education context among English-speaking adolescents. The hypothesized three-factor structure of the BPNSQ was not supported and more research is needed to evaluate the English version in the physical education context.  相似文献   
996.
The purposes of this study were: (a) to analyze the factors determining the quality of relationships between a novice physical education (PE) teacher and his students’ families and (b) understand the implications of these relationships for his professional identity. The data stemmed from detailed teacher’s diaries written by the participant throughout his first five years of teaching. The data analysis followed several rounds of cyclical inductive-deductive processes in order to identify and classify the patterns related to the aforementioned purposes. The results, presented in two sections, show two distinct sets of factors, which, respectively, had very different implications for the development of the teacher’s professional identity. On the one hand, in the first three years of teaching, there appeared 11 specific ‘struggle factors’ (6 socio-cultural and structural factors and 5 family prejudices toward PE) that threatened the teacher’s initial pedagogical passion and lead to a great deal of hesitation and discouragement on his part; on the other hand, in the fourth and fifth years, due to the teacher’s ongoing commitment and (self-)reflective practice, there emerged eight ‘success factors’ (one from the families and seven from the teacher) that transformed his previous discouragement into hope and self-confidence. Besides the detailed analysis of all these factors and their implications, some additional recommendations for PE teacher education programs and further research are provided.  相似文献   
997.
The main purpose of this study was to compare the effect of the constant load and self-paced exercise with similar total work on autonomic control after endurance exercise. Ten physically active men were submitted to (i) a maximal incremental exercise test, (ii) a 4-km cycling time trial (4-km TT), and (iii) a constant workload test with identical total external work performed at 4-km TT. Gas exchange was measured throughout the tests, while blood lactate, heart rate, and heart rate variability (HRV) were measured during the passive recovery. Power output measured at the last lap (i.e. 3600–4000?m) of 4-km TT (316?±?89?W) was statistically higher than power output measured at the end of the constant workload exercise (211?±?42?W). The 4-km TT produced higher values of blood lactate concentration (8.8?±?2.1?mmol?L?1) than the constant workload test (7.8?±?2.1?mmol?L?1). The heart rate recovery measured at 60?s (constant workload: 37?±?7?bpm; 4-km TT: 30?±?6) and 120?s (constant workload: 57?±?9?bpm; 4-km TT: 51?±?9?bpm) were higher in the constant workload than in the self-paced exercise. The HRV (i.e. RMSSD30s) was statistically higher in the constant load exercise measured at 120, 420, 450, 480, 540, and 570?s than the self-paced exercise. These findings suggest that the autonomic control responses were dependent of the endurance exercise modalities, with parasympathetic activity being delayed after self-paced exercise, as evidenced by post-exercise heart rate indices.  相似文献   
998.
This study aimed to determine the effect of different percentages of body weight support (BWS) on spatiotemporal step characteristics during running. 26 endurance runners (age: 37 ± 9 years) completed a running treadmill protocol consisting of 6 different conditions (BWS combinations: 0–50%), with velocity maintained at 12 km/h. Each condition lasted 1 minute. Step angle, ground contact time (CT), flight time (FT), step length (SL) and frequency (SF), and duration of phases during stance time (phase1: initial contact; phase2: midstance; phase3: propulsion) were measured for every step during the test using a photoelectric cell system. Compared with the baseline condition (100% BW), FT was longer, CT was shorter, SL was longer, SF was lower, and the step angle was higher with each increase in BWS (p < 0.05). Also, some changes were observed in the duration of phases during stance time: phase1 did not experience changes across experimental conditions (p = 0.096), phase2 decreased and phase3 increased as BW was supported (p < 0.05). These results indicate that as BW was supported, runners showed longer FT and SL, shorter CT, lower SF, and greater step angle as well as some changes in the phases during the ground contact. Therefore, this study highlights the effect of different percentages of BWS on spatiotemporal parameters.  相似文献   
999.
This study aimed to investigate the acute effects of two barbell hip thrust-based (BHT) post-activation potentiation (PAP) protocols on subsequent sprint performance. Using a crossover design, eighteen handball athletes performed maximal 15-m sprints before and 15s, 4min and 8min after two experimental protocols consisting of BHT loaded with either 50% or 85% 1RM (50PAP and 85PAP, respectively), in order to profile the transient PAP effects. The resulting sprint performances were significantly impaired at 15s only after the 85PAP protocol, which induced likely and very likely greater decreases compared to the 50PAP. At 4min and 8min, significant improvements and very likely beneficial effects were observed in the 10m and 15m performances following both protocols. Significant differences were found when comparing the two PAPs over time; the results suggested very likely greater performance improvements in 10m following the 85PAP after 4min and 8min, and possible greater performance improvements in 15m after 4min. Positive correlations between BHT 1RMs values and the greatest individual PAP responses on sprint performance were found. This investigation showed that both moderate and intensive BHT exercises can induce a PAP response, but the effects may differ according to the recovery following the potentiating stimulus and the individual`s strength level.  相似文献   
1000.
Cardiorespiratory fitness (CRF) is associated with health benefits in children, improving cardiac morphology, cardiovascular disease risk factors, and biological outcomes. This study aimed to examine the substitution effects of displaying a fixed duration of sedentary time with a fixed duration of physical activity (PA) at different intensities on children’s CRF. A total of 315 children (136 boys) were assessed (age: 10.6 ± 0.6 years old). Outcomes at baseline and follow-up (16-months) were CRF determined using a maximal cycle test and sedentary time and PA measured with accelerometers. Data were analysed by isotemporal substitution analyses estimating the effect of reallocating 30 min/day of sedentary time by light (LPA), moderate (MPA) and vigorous physical activity (VPA) on CRF. VPA was positively and significantly associated with CRF cross-sectional (β = 0.026, < 0.001) and prospectively (β = 0.010, < 0.001). Reallocating 30 min/day of sedentary time into VPA was positively cross-sectionally (β = 0.780, < 0.001) and prospectively (β = 0.303, < 0.05) associated with CRF. Conversely, relocating 30-minutes of sedentary time into 30 minutes of LPA and MPA was not associated with CRF. These results suggest that reallocating an equal amount of time from sedentary into VPA is cross-sectional and prospectively associated with a favourable CRF.  相似文献   
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