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Gisela Pujol-Vazquez Leonardo Acho Saleh Mobayen Amelia Nápoles Vega Pérez 《Journal of The Franklin Institute》2018,355(10):4077-4096
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
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Lucas Rosiello Trojbicz Mayara Vieira Damasceno Leonardo Alves Pasqua Arthur Fernandes Gáspari Adriano Eduardo Lima-Silva 《European Journal of Sport Science》2018,18(6):842-850
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
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Alessandro N. Vargas Gisela Pujol Leonardo Acho 《Journal of The Franklin Institute》2017,354(1):332-344
The paper presents results for the second moment stability of continuous-time Markov jump systems with quadratic terms, aiming for engineering applications. Quadratic terms stem from physical constraints in applications, as in electronic circuits based on resistor (R), inductor (L), and capacitor (C). In the paper, an RLC circuit supplied a load driven by jumps produced by a Markov chain—the RLC circuit used sensors that measured the quadratic of electrical currents and voltages. Our result was then used to design a stabilizing controller for the RLC circuit with measurements based on that quadratic terms. The experimental data confirm the usefulness of our approach. 相似文献
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Stefano Basaglia Leonardo Caporarello Massimo Magni Ferdinando Pennarola 《International Journal of Information Management》2010
Previous research considering a normative perspective for fostering knowledge integration at the team level of analysis underscores that teams are often reluctant to share important knowledge among their members. In the attempt to provide a wider perspective on team knowledge integration, we take a different perspective, basing our arguments on team climate theoretical framework. Specifically, we argue that an autonomy and experimental climate (i.e. shared perception that the team supports autonomous action and experimentation and risk taking) can favor the team's ability to integrate members’ knowledge. Indeed, focusing on members’ willingness to contribute to team well-being, team autonomy and experimental climate may enhance the team's capability to integrate knowledge enabled by the IT infrastructure (IT knowledge integration capability). We tested our research model on a sample of 410 members and leaders of 69 organizational work teams. Results show the critical role played by team climate in favoring IT knowledge integration capability, which in turn affects team outcomes. 相似文献
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Marcus Peikriszwili Tartaruga Jeanick Brisswalter Leonardo Alexandre Peyré-Tartaruga Aluísio Otávio Vargas Ávila Cristine Lima Alberton Marcelo Coertjens 《Research quarterly for exercise and sport》2013,84(3):367-375
In this study, we analyzed the relationship between running economy (RE) and biomechanical parameters in a group running at the same relative intensity and same absolute velocity. Sixteen homogeneous male long-distance runners performed a test to determine RE at 4.4 m.s-1, corresponding to 11.1% below velocity at the ventilatory threshold. We found significant correlations between RE and biomechanical variables (vertical oscillation of the center of mass, stride frequency, stride length, balance time, relative stride length, range of elbow motion, internal knee, ankle angles at foot strike, and electromyographic activity of the semitendinosus and rectus femoris muscles). In conclusion, changes in running technique can influence RE and lead to improved running performance. 相似文献
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Leonardo Martín Pérez Francesc Codony Daniela López Leyton Mariana Fittipaldi Bárbara Adrados Jordi Morató 《Journal of Zhejiang University. Science. B》2010,11(1):27-29
Helicobacter pylori are ubiquitous Gram-negative bacteria with a high estimated level of infection in the world populations, but a majority of
the infected persons are asymptomatic. This pathogen has been classified by the World Health Organization as a class I carcinogen
and recognized as the causal agent of most peptic ulcers and chronic gastritis that might lead to stomach cancer. Although
not all the transmission pathways of these bacteria into humans have been properly identified, enough data have suggested
that the oral-oral or fecal-oral ones are the main infection routes. Helicobacter pylori have been detected in non-treated water and in drinking water, which suggested that water might be an important infection
source. As childhood is the critical period of infection, the aim of the present work was to examine the presence of Helicobacter pylori in soil samples from public playing areas of Spanish parks. 相似文献
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Leonardo Fuentealba Hernandez Lotte Schenk-Danzinger M. J. Langeveld Per Kirstein Richard D'Aeth R. E. Hennion Fritz Bohnsack Hans Thomae Oskar Anweiler L. J. Pongratz G. De Landsheere Hans Möckelmann 《International Review of Education/Internationale Zeitschrift für Erziehungswissenschaft/Revue internationale l'éducation》1961,7(3):358-376
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Hugo T.M. Kussaba João Y. Ishihara Leonardo R.A.X. Menezes 《Journal of The Franklin Institute》2019,356(6):3797-3810
This paper proposes a robust version of the unscented transform (UT) for one-dimensional random variables. It is assumed that the moments are not exactly known, but are known to lie in intervals. In this scenario, the moment matching equations are reformulated as a system of polynomial equations and inequalities, and it is proposed to use the Chebychev center of the solution set as a robust UT. This method yields a parametrized polynomial optimization problem, which in spite of being NP-Hard, can be relaxed by some algorithms that are proposed in this paper. 相似文献