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In this study, the issue of simultaneous fault detection and control (SFDC) for a class of switched linear systems with input and state delays is being addressed. A detector/controller unit (dynamic observer/observer-based controller) is suggested for a residual generation that simultaneously takes into account the control and fault detection objectives using specific performance indices. It is assumed that the delay will fluctuate within a range with a lower bound that is not zero. Based on a Lyapunov–Krasovskii functional (LKF), and thanks to the free-weighting matrix and projection lemma, a new sufficient condition for developing a new method is put forth in terms of a set of linear matrix inequalities (LMIs). To illustrate how well the suggested results work, the proposed method is applied to a vehicle roll dynamic. [ABSTRACT FROM AUTHOR]

This paper presents a detailed investigation of both normal and intruder states in 98Mo nucleus in the E ≥ 3 MeV. We considered all reported intruder energy levels for this nucleus, 0+2, 2+1, 4+1, 4+2, 2+2, and also the quadrupole transitions which originated from these levels. A mixing formalism based on the combination of U(5) and O(6) dynamical symmetries of the interacting boson model is used in the Hamiltonian and wavefunctions for, respectively, N- and (N + 2)-boson spaces. The weight of each space is determined by the calculation of theoretical quadrupole transition rates and compared with their experimental counterparts. By using these weights, the expectation values of the pure U(5) and O(6) Hamiltonians and also the total Hamiltonian that contains these limits and mixing terms are calculated for different levels, too. The results show that normal energy levels and quadrupole transition between them can be described satisfactory in comparison with experimental counterparts by using the pure U(5) Hamiltonian in the only N-boson space. For intruder levels and quadrupole transition originating from them or holding between normal and intruder states, the mixed formalism of Hamiltonian and wavefunctions increases the efficiency of theoretical formalisms and suggests exact results. [ABSTRACT FROM AUTHOR]

Entangled networks of carbon nanofibers are characterized both mechanically and electrically. Results for both tensile and compressive loadings of the entangled networks are presented for various densities. Mechanically, the nanofiber ensembles follow the micromechanical model originally proposed by van Wyk nearly 70 years ago. Interpretations are given on the mechanisms occurring during loading and unloading of the carbon nanofiber components. [ABSTRACT FROM AUTHOR]

The third author et al. in 2013, introduced and studied the concept of auto-Bell groups. A group G is said to be n-auto-Bell if [xn, α] = [x, αn], for all x in G, α in Aut(G) and any integer n ≠ 0, 1. Let Ln(G) be the nth-absolute centre of the group G, then some sharp bounds for the exponents of G/L2(G) and G/L3 (G) are constructed, when G is an n-auto-Bell abelian or n-auto-Bell groups. Finally, we show that <øx, α> is nilpotent of class at most 4, for every inner automorphism øx induced by an element x of G and α in Aut(G), when G is a 3-auto-Engel group. [ABSTRACT FROM AUTHOR]

For suitable Banach spaces X and Y with Schauder decompositions and a suitable closed subspace M of some compact operator space from X to Y, it is shown that the strong Banach-Saks-ness of all evaluation operators on M is a sufficient condition for the weak Banach-Saks property of M, where for each x ε X and y* ε Y*, the evaluation operators on M are defined by ϕx(T) = Tx and Ψy*(T) = T*y* : [ABSTRACT FROM AUTHOR]

Background and Aim: Regard with the importance of balance in daily activities especially in sport activities and understanding the important factor affecting it, the purpose of this study was to compare the role of vision system on dynamic postural stability of young women with men elite athletes. Materials and Methods: Twenty six young women and men elite swimmer were chosen from the available society. They were divided in two groups according to body mass index. Each subject performed postural stability tests for 6 trials with open and close eyes (3 trials with open and 3 trial with close eyes) that each trial was taken for 30 seconds and with 10 seconds rest between each of them. Balance index in anterior- posterior and medial- lateral directions were calculated and independent t test was used to compare between groups. Result: Results show that men swimmer are more depended to vision than women swimmer in maintaining retrieval postural stability (p= 0.001), while most impairment in maintaining postural stability in both groups occur in lack of vision status in anterior- posterior direction (p= 0.001). Conclusion: The findings of this study can be used to design training programs to prepare athletes. Key words: balance, vision, athlete, control [ABSTRACT FROM AUTHOR]

A nonlinear method is proposed to calculate the adhesion energy (strain energy release rate) of stiction-failed μcantilever beams with large deflections. The proposed method uses a nonlinear theory for the deflection of a beam and an energy method for calculating the beam’s strain energy. It is shown that current models used to predict μcantilevers’ profile breakdown when the beam deflection exceeds 27% of the thickness due to the onset of longitudinal stresses in the μcantilevers. Because the present model captures longitudinal stresses in the μcantilevers and consequently their contribution to the strain energy, mode I and mode II contributions to the adhesion energy can be discerned. A set of experiments are performed using the peel test scheme with poly-Si μcantilever stiction failed on a poly-Si substrate. Results processed using the present model indicate that the adhesion energy of the μcantilevers actually increases with increased height of the μcantilever’s base. This increase in the adhesion energy is attributed to the manner of loading that the μcantilevers experience which leads to increased contact area and the concomitant increase of adhesion. [ABSTRACT FROM AUTHOR]

Background and Aim: With regard to importance of the role of balance in performance of daily activity especially in exercise activity and necessary to identify the factors that influence the balance, the purpose of this study was to survey the effect of lower limb muscle fatigue on balance in elite young athletes. Materials and Methods: For this purpose, 15 young elite swimmers with a mean age and body mass index 17±0.7 and 21.62±0.5 during the two test phase, were studied. All participants performed the postural Stability and limit of stability tests in six for each test (three repetitions before and three repetitions after fatigue protocol by Wingate test)on the balance Biodex system. Values obtained by the system of the total, anterior - posterior, medial - lateral, anterior, anterior - right, anterior- left, posterior, posterior - right and posterior left index, were analyzed using paired sample t-test(P≤0.05). Results: Results showed that fatigue caused a significantly influence the anterior - posterior, medial - lateral, posterior, left and posterior -- left index. Conclusion: With considering the specificity of training principle, the results can be helpful in the design of exercises involving the lower limb muscles in the specific direction. [ABSTRACT FROM AUTHOR]

Abstract: A unique type of nonwoven carbon material has been developed which is flexible, resilient, and produced at modest temperature and near ambient pressure using catalytic deposition. This material is comprised entirely of nanoscale carbon fibers, which are extensively interlaced to create a coherent, bulk material. The structure and basic mechanical and electrical properties of this material were investigated through cyclic compression and in situ resistance measurement. The material was highly elastic and capable of being repeatedly compressed without disintegration. The mechanical response varied with density, and the density was controlled by the amount of catalyst used. The material exhibited a high electrical resistivity, which varied nonlinearly with compression. [Copyright &y& Elsevier]

Abstract: The main objective of fault tree analysis method is to estimate the “Top Event occurrence probability”. This requires determination of failure time distribution functions also known as “Bathtub Curves” for each of the system elements/events. This paper introduces a novel method to determine the failure time distribution functions using possibility theory. For this purpose, fuzzy‐bathtub distributions using expert opinions are generated for basic events and fuzzy formulas are derived for static and dynamic gates fault tree constructions. This process completed by proposed fuzzy Monte Carlo simulation throughout the preferred operational time and uses the actual time‐to‐failure data. Accordingly, the Top Event failure curve and the reliability profile of the system are depicted based on the defuzzificated basic‐events' bathtub‐failure‐rates. The results show that the proposed method not only is feasible and powerful but can also be accurate more than the other probabilistic and possibilistic techniques because of the component failure rates follow the real failure distributions. [ABSTRACT FROM AUTHOR]