Recently, legged robots have attracted considerable attention as highly mobile rovers for planetary exploration. However, the surfaces of celestial bodies such as Mars and the Moon are primarily loose, causing slippag...
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The cardiac muscle is elastic and deformable. Pushing a catheter in contact with the cardiac muscle surface to conduct focal energy-based ablative therapies, such as RF ablation, requires an adequate electrode-tissue ...
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作者：
Kawashita, MishioKawashita, WakakoMathematics Program
Graduate School of Advanced Science and Engineering Hiroshima University Higashihiroshima739-8526 Japan Electrical
Systems and Control Engineering Program Graduate School of Advanced Science and Engineering Hiroshima University Higashihiroshima739-8527 Japan
In this paper, the inverse problem of the wave equation by the enclosure method for a medium with multiple types of cavities is discussed. In the case considered here, the sign of the indicator function of the enclosu...
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Achieving asymptotical cooperative goal for multi-agent systems(MASs)with non-autonomous leaders(i.e.,leaders with nonzero inputs)is a critical but challenging *** approach is to use discontinuous controllers which ma...
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Achieving asymptotical cooperative goal for multi-agent systems(MASs)with non-autonomous leaders(i.e.,leaders with nonzero inputs)is a critical but challenging *** approach is to use discontinuous controllers which may cause chattering phenomenon in practical *** to achieve the asymptotical goal via a chattering free cooperative controller remains to be open so *** this paper,an adaptive continuous controller is designed to achieve zero error consensus tracking in multiple Lur’e systems with a non-autonomous leader under directed switching ***,an unknown input observer(UIO)based on relative outputs is given to estimate the relative full *** an adaptive continuous controller is designed by introducing a decay function which remains positive into the term that plays the role of eliminating the impacts of leader’s nonzero ***,by using multiple Lyapunov functions(MLFs)technique,it is proven that zero error consensus tracking can be achieved if the average dwell time(ADT)is greater than a positive ***,theoretical result is verified by performing simulations on Chua’s *** with existing work,the proposed controller can not only achieve asymptotical consensus,but also is chattering free.
作者：
Kawashita, MishioKawashita, WakakoMathematics Program
Graduate School of Advanced Science and Engineering Hiroshima University Higashihiroshima739-8526 Japan Electrical
Systems and Control Engineering Program Graduate School of Advanced Science and Engineering Hiroshima University Higashihiroshima739-8527 Japan
In this article, the role of "shortest length" is discussed concerning the inverse problems with the time dependent enclosure method. In the beginning, the inclusions embedded in a non-layered medium are han...
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Cobalt titanate, CoTiO3, is a honeycomb antiferromagnet recently confirmed experimentally to host Dirac magnons, topological spin-orbit excitons, and chiral phonons. Here, we investigate a magnon gap at the zone cente...
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Cobalt titanate, CoTiO3, is a honeycomb antiferromagnet recently confirmed experimentally to host Dirac magnons, topological spin-orbit excitons, and chiral phonons. Here, we investigate a magnon gap at the zone center which calls for a refined spin Hamiltonian. We propose a microscopic model for the magnon gap and attribute it to a lattice-distortion (phonon)-induced higher-order spin interaction. Strong magnetoelastic coupling in CoTiO3 is also evident in Raman spectra, in which the magnetic order exerts a stronger influence on phonons corresponding to in-plane ionic motions than those with out-of-plane motions. We further examine the evolution of the zone-center magnons in a high magnetic field up to 18.5 T via THz absorption spectroscopy measurements. Based on this field dependence, we propose a spin Hamiltonian that not only agrees with magnon dispersion measured by inelastic neutron scattering but also includes fewer exchange constants and a realistic anisotropy term. Our work highlights the broad implications of magnetoelastic coupling in the study of topologically protected bosonic excitations.
The cardiac muscle is elastic and deformable. Pushing a catheter in contact with the cardiac muscle surface to conduct focal energy-based ablative therapies, such as RF ablation, requires an adequate electrode-tissue ...
The cardiac muscle is elastic and deformable. Pushing a catheter in contact with the cardiac muscle surface to conduct focal energy-based ablative therapies, such as RF ablation, requires an adequate electrode-tissue contact surface to transfer the energy to the target site. In this regard, the relationship between the contact force (CF) and the resulting mechanical response is still unclear, in particular, the insertion depth (ID) and the diameter of the surface deformation. The objective of this study was to quantify these relationships using an ex vivo model and a computational model. A rigid bar with a 2.3 mm diameter blunt tip (mimicking a 7Fr standard ablation catheter) was placed at a perpendicular orientation on a fragment of the porcine heart. CF values ranged from 10 to 80g. We used ANSYS to build a Mooney-Rivlig model of 3 parameters based on hyperelastic material and to simulate the same conditions as in the experiments. The experimental results showed a strong linear correlation between CF and insertion depth ID ( $\mathrm{R}^{2}=0.97, \mathrm{P} < 0.001$ ), from $0.7 \pm 0.3$ mm at 10 gto $6.9 \pm 0.1$ mm at 80 g. We also found a strong linear correlation between CF and minor and major diameters of the surface deformation assessed, from $4.0 \pm 0.4$ mm at 20 g to $10.3 \pm 0.0$ mm at 80 g ( $\mathrm{R}^{2}=0.96$ ), and from $6.4 \pm 0.7$ mm at 20 g to $16.7 \pm 0.1$ mm at 80 g ( $\mathrm{R}^{2}=0.95$ ), respectively. A descent gradient algorithm was used to minimize the mean square error (MSE) between the experimental and computational results of ID for the 10 values of CF. After trying different combinations for the3 parameters of the Mooney-Rivlig model, an optimal fit was achieved after 5 iterations, with an error of less than 0.55 mm for ID. This same mode was then used to predict the diameter of the surface deformation, obtaining an error of less than 0.65 mm. The results confirm that a Mooney-Rivlig model of three parameters based on
This paper addresses the problem of distributed online generalized Nash equilibrium (GNE) learning for multicluster games with delayed feedback information. Specifically, each agent in the game is assumed to be inform...
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Phocid seals can detect fish from distances up to 180 meters solely using undulating whiskers. The unique undulating surfaces of these whiskers have been found to minimize vortex-induced vibrations (VIVs). In our prev...
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ISBN:
(数字)9798350388039
ISBN:
(纸本)9798350388046
Phocid seals can detect fish from distances up to 180 meters solely using undulating whiskers. The unique undulating surfaces of these whiskers have been found to minimize vortex-induced vibrations (VIVs). In our previous work, we measured the ratios of undulation wavelength (λ) to mean diameter $\left(D_{m}\right),\left(\lambda / D_{m}\right)$ in both harbor and grey seals, yielding values of approximately 4.36 and 4.63, respectively. In this study, we delve into the significance of the $\lambda / D_{m}$ ratio to the vibration responses of seal whiskers in a fluid flow. We conducted comprehensive fluid-structure interaction studies using COMSOL Multiphysics®, wherein we studied vibration responses of harbor and grey seal whisker structures with diverse $\lambda / D_{m}$ values in the oncoming flow. Our results indicate that seal whiskers exhibited a trough in their VIV responses and a peak in wake-induced vibration (WIV) responses at $\lambda / D_{m}$ values around 4 to 5. Our findings could imply that the evolutionary optimization of the $\lambda / D_{m}$ value enables seal whiskers with resistance to VIV and sensitivity to WIV.
Postdoctoral training positions are becoming more common in the human factors and ergonomics (HFE) discipline. However, conversations related to training in the HFE discipline have largely focused on undergraduate and...
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