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Vibrational resonance: a study with high-order word-series averaging

approaches, with word-series high-order averaged systems may be derived without having to compute the associated change of variables. The use of word series techniques is not confined to averaging; word series may be applied to compute normal forms of discrete or continuous dynamical systems [ 13 ], [ 14 ], [ 15 ], find formal invariants of differential systems [ 14 ], analyze numerical integrators [ 13 ], [ 1 ], etc. Section 2 provides a brief summary of the averaging technique we employ. It should be emphasized that while, for the sake of simplicity, this summary is

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Motivational Antecedents of Well-Being and Health Related Behaviors in Adolescents

al., 2001 ; Duda and Nicholls, 1992 ), we also assumed that satisfaction and boredom in school would be negatively related. As the motivational mechanisms within this research were assumed to be comparable across gender groups, we tested the hypothesized model for both boys and girls. We expected the model to be invariant across gender. Methods Participants A representative sample of 967 Spanish students (475 boys and 492 girls) between 11 and 16 years old (M = 13.54 ± 1.8 years) participated in this study. We excluded 110 students from the initial

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On the integrability of the Hamiltonian systems with homogeneous polynomial potentials

always a first integral because { H , H } = 0. Two functions H and F from ℂ 4 to ℂ are functionally independent when their gradients are linearly independent at all points of ℂ 4 except perhaps in a zero Lebesgue measure set. Here a Hamiltonian system (1) with two degrees of freedom is integrable if it has two functional independent first integrals H and F . This definition of integrability restricted to real Hamiltonian systems coincides with the Liouville integrability, see for instance [ 1 , 2 ]. First we summarize the classification of all

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Can aphids be controlled by fungus? A mathematical model

spring until harvest. In natural conditions, while the fungus is always present, aphids instead immigrate from the surroundings areas in the cereal field. Aphids are lost from the system, because they are killed by natural enemies or by infection by the fungus, or by winged emigration. 3 Model Let P be the biomass of plant material; S be the number of susceptible aphids; E the number of exposed aphids, i.e. infected by developing fungus but unable to transmit it, and F a measure of the amount of fungus in the environment, which is renewed whenever an

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The World’s Oldest Profession? Employment-Age Profiles from the Transactional Sex Market

national household surveys on employment-age profiles in the transactional sex market. A major barrier to measuring determinants of employment in transactional sex is the dearth of data on female participation in transactional sex from general population surveys. The Demographic and Health Surveys (DHS), collected in over 90 low-and middle-income countries and often used in economic analyses of risky sexual behavior including participation in the transactional sex market (e.g., see De Walque 2008, Fortson 2009, Friedman 2016 , Lucas and Wilson 2017 ), typically only

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Factors Affecting the Development of Voluntary Pension Schemes in CEE Countries: A Panel Data Analysis

current working generation should prolong their working lives or/and make additional savings. In the past decade, many CEE countries took measures to boost the supplementary savings for retirement. They included introducing new types of voluntary pension schemes and more favourable financial incentives. Nonetheless, according to OECD simulations of the modelled pension replacement rates, the voluntary pensions in CEE countries, except for Czechia, are still not developed enough to substantially increase the average adequacy of future pension benefits (OECD 2013). As

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Adjusting for Measurement Error in Retrospectively Reported Work Histories: An Analysis Using Swedish Register Data

Jeffreys’s Prior.” Journal of the American Statistical Association 86(416): 981–986. Doi: https://doi.org/10.1037/0033-295X.95.4.471 . Jäckle, A. 2008. Measurement error and data collection methods: Effects on estimates from event history data. Technical report, Institute for Social and Economic Research, ISER. Available at: https://www.iser.essex.ac.uk/research/publications/working-papers/iser/2008-13.pdf (accessed February 2019). Jeffreys, H. 1946. “An Invariant Form for the Prior Probability in Estimation Problems.” Proceedings of the Royal Society

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Anatomical characterization of ADHD using an atlas-based analysis: A diffusion tensor imaging study

, Evans A, Mazziotta J, Mori S. Atlas-based whole brain white matter analysis using large deformation diffeomorphic metric mapping: application to normal elderly and Alzheimer’s disease participants. Neuroimage 2009; 46(2): 486-99. 23. Ennis DB, Kindlmann G. Orthogonal tensor invariants and the analysis of diffusion tensor magnetic resonance images. Magn Reson Med 2006; 55(1): 136-46. 24. Bilgen M. Imaging corticospinal tract connectivity in injured rat spinal cord using manganese-enhanced MRI. BMC Medical Imaging 2006; 6

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What Determines Export Performances in High‑tech Industries

.1 % 24.7 % Manufacture of consumer electronics 3.1 % 27.8 % Manufacture of instruments and appliances for measuring, testing and navigation; watches and clocks 9.6 % 8.9 % Manufacture of irradiation, electro-medical and electrotherapeutic equipment 2.6 % 0.4 % Manufacture of optical instruments and photographic equipment 1.8 % 1.4 % Manufacture of magnetic and optical media 0.2 % 0.1 % Manufacture of air and spacecraft and related machinery 17.6 % 2.8 % Source: Authors’ own calculations based on the

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Intermittent transition to chaos in vibroimpact system

this information too, such as short time Fourier transform, Wigner distributions, etc.). Wavelet transform is capable of providing the time and frequency information simultaneously, hence giving a time-frequency representation of the signal. The WT was developed as an alternative to the short time Fourier Transform (STFT). Like the FT the continuous wavelet transform (CWT) uses inner products to measure the similarity between a signal and an analyzing function. In the FT the analyzing functions are the complex exponents e jωt . The resulting transform is a

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