A Damped Oscillator Model for Infrared Spectra of Formamide in the Liquid State

Clinicians and experimentalists routinely estimate vagal-cardiac nerve traffic from respiratory sinus arrhythmia. However, evidence suggests that sympathetic mechanisms may also modulate respiratory sinus arrhythmia. Our study examined modulation of respiratory sinus arrhythmia by sympathetic outflow. We measured R-R interval spectral power in 10 volunteers that breathed sequentially at 13 frequencies, from 15 to 3 breaths/min, before and after β-adrenergic blockade. We fitted changes of respiratory frequency R-R interval spectral power with a damped oscillator model: frequency-dependent oscillations with a resonant frequency, generated by driving forces and modified by damping influences. β-Adrenergic blockade enhanced respiratory sinus arrhythmia at all frequencies (at some, fourfold). The damped oscillator model fit experimental data well (39 of 40 ramps; r = 0.86 ± 0.02). β-Adrenergic blockade increased respiratory sinus arrhythmia by amplifying respiration-related driving forces ( P < 0.05), without altering resonant frequency or damping influences. Both spectral power data and the damped oscillator model indicate that cardiac sympathetic outflow markedly reduces heart period oscillations at all frequencies. This challenges the notion that respiratory sinus arrhythmia is mediated simply by vagal-cardiac nerve activity. These results have important implications for clinical and experimental estimation of human vagal cardiac tone.

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Surface-like over-damped oscillator model to interpret impedance spectroscopy data

Journal of Electroanalytical Chemistry ◽

10.1016/j.jelechem.2016.08.012 ◽

2016 ◽

Vol 778 ◽

pp. 74-79 ◽

Cited By ~ 2

Author(s):

F.C.M. Freire ◽

T.M. Andrade

Keyword(s):

Impedance Spectroscopy ◽

Oscillator Model ◽

Spectroscopy Data ◽

Damped Oscillator

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Band Analysis of Temperature-Dependent Near-Infrared Spectra of Oleic Acid in the Pure Liquid State by the Analytic Geometric Approach

Applied Spectroscopy ◽

10.1366/000370203322640189 ◽

2003 ◽

Vol 57 (12) ◽

pp. 1539-1550 ◽

Cited By ~ 3

Author(s):

Katsue Koashi ◽

Makio Iwahashi ◽

Yukihiro Ozaki

Keyword(s):

Oleic Acid ◽

Infrared Spectra ◽

Liquid State ◽

Near Infrared ◽

Geometric Approach ◽

Pure Liquid ◽

Temperature Dependent ◽

Near Infrared Spectra

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Infrared spectra of InSe

Canadian Journal of Physics ◽

10.1139/p81-024 ◽

1981 ◽

Vol 59 (2) ◽

pp. 198-201 ◽

Cited By ~ 10

Author(s):

S. Jandl ◽

M. Banville ◽

J. Deslandes

Keyword(s):

Infrared Spectra ◽

Direct Evidence ◽

Oscillator Model ◽

Space Group ◽

Group Assignment ◽

Consistent Description ◽

Dynamical Charge

The infrared spectra analyses of InSe with the independent oscillator model and with the factorized model give results consistent with the β polytype ([Formula: see text] space group) assignment. It is shown that only the independent oscillator model gives a consistent description of the spectra and provides direct evidence for a large dynamical charge contribution to the interactions.

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A damped oscillator model of the 50-day oscillation in the length of the day

Chinese Astronomy and Astrophysics ◽

10.1016/0275-1062(88)90024-0 ◽

1988 ◽

Vol 12 (1) ◽

pp. 48-54 ◽

Cited By ~ 2

Author(s):

Zhi-an Li ◽

Clark R. Wilson

Keyword(s):

Oscillator Model ◽

Length Of The Day ◽

Damped Oscillator

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Damped-oscillator model of adaptive response and its consequences

International Journal of Low Radiation ◽

10.1504/ijlr.2020.113538 ◽

2020 ◽

Vol 11 (3/4) ◽

pp. 186

Author(s):

Yehoshua Socol ◽

Yair Y. Shaki ◽

Ludwik Dobrzyński

Keyword(s):

Adaptive Response ◽

Oscillator Model ◽

Damped Oscillator

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Raman and infrared spectra and the structure of the dimethyl ester of 2,2,4,4-tetramethylglutaric acid

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19832072 ◽

1983 ◽

Vol 48 (7) ◽

pp. 2072-2078 ◽

Cited By ~ 6

Author(s):

Jiří Dybal ◽

Jan Štokr ◽

Bohdan Schneider

Keyword(s):

Temperature Dependence ◽

Infrared Spectra ◽

Liquid State ◽

Dimethyl Ester ◽

Local Order ◽

Dipolar Interactions ◽

Liquid States ◽

Solid And Liquid States

Raman and infrared spectra of the dimethyl ester of 2,2,4,4-tetramethylglutaric acid in the solid and liquid states and the temperature dependence of the spectra were measured. The behaviour of some bands in the spectra indicates the presence of three conformers in the liquid state. Local order of the molecules due to dipolar interactions of ester groups was observed.

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Research of Contact Response of an Elastic Sphere Impacting a Rigid Plate Based on the Mass-Spring-Damped Oscillator Model and Dimensionless Parameter \omega_\Omega

10.20855/ijav.2020.25.21523 ◽

2020 ◽

Vol 25 (2) ◽

pp. 141-152

Author(s):

Yang Yang ◽

Qingliang Zeng ◽

Lirong Wan ◽

Liang Wang ◽

Guangjun Yin

Keyword(s):

Contact Force ◽

Material Properties ◽

Dimensionless Parameter ◽

Contact Theory ◽

Oscillator Model ◽

Force Model ◽

Contact Response ◽

Mass Spring ◽

The Impact ◽

Damped Oscillator

The contact theory, such as the Hertz theory and Hunt-Crossley model can just solve the contact response when the sphere goes to the maximum compression but can't solve the contact process. In traditional research the impact process is considered as a single degree of freedom dynamical spring-damping system, however, the calculated contact force is much greater than the actual one. Based on the shortage of the conducted studies, a new dimensionless parameter Omega is proposed in this paper, the mass-spring-damped oscillator model (MSDOM) and the new contact theory with the consideration of the sphere mass and Omega are established. The correctness of the theoretical model is verified by 3D simulation, and the optimal contact force model is obtained. Furthermore, influence rules of material properties and contact parameters on contact response were studied. The results show that the contact deformation, velocity, piecewise nonlinear contact force and acceleration based on MSDOM and Omega are effective to calculate the contact response. The contact stiffness, damping, material properties of sphere and elastic modulus of the plate have different influence on the contact response while the Poisson's ratio nu_2 has little effect on it.

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