Search results for "DEFLECTION"
showing 10 items of 101 documents
Shakedown optimal design of reinforced concrete structures by evolution strategies
2000
Approaches the shakedown optimal design of reinforced concrete (RC) structures, subjected to variable and repeated external quasi‐static actions which may generate the well‐known shakedown or adaptation phenomenon, when constraints are imposed on deflection and/or deformation parameters, in order to simulate the limited flexural ductility of the material, in the presence of combined axial stress and bending. Within this context, the classical shakedown optimal design problem is revisited, using a weak upper bound theorem on the effective plastic deformations. For this problem a new computational algorithm, termed evolution strategy, is herein presented. This algorithm, derived from analogy …
Robust Output-Feedback Based Fault-Tolerant Control of Active Suspension with Finite-Frequency Constraint ★ ★This work is partly supported by Nationa…
2015
Abstract In this paper, the H∞ fault-tolerant control (FTC) problem of active suspensions with finite-frequency constraints is investigated. A full-car model is employed in the controller design such that the heave, pitch and roll motions can be simultaneously controlled. Both the actuator faults and external disturbance are considered in the controller design. As the human body is more sensitive to the vertical vibration in 4-8Hz, robust H∞ control with finite frequency constraints is designed. From the practical perspective, a robust dynamic output-feedback controller with fault tolerant ability is proposed, while other performances such as suspension deflection and actuator saturation ar…
Static output-feedback controller design for vehicle suspensions: an effective two-step computational approach
2014
In this study, a novel two-step methodology is applied in designing static output-feedback controllers for a class of vehicle suspension systems. Following this approach, an effective synthesis of static output-feedback controllers can be carried out by solving two consecutive linear matrix inequality optimisation problems. To illustrate the main features of the proposed design strategy, two different static output-feedback H 8 controllers are designed for a quarter-car suspension system. The first of those controllers uses the suspension deflection and the sprung mass velocity as feedback information, whereas the second one only requires the sprung mass velocity to compute the control acti…
Static output-feedback control for vehicle suspensions: a single-step linear matrix inequality approach
2013
In this paper, a new strategy to design static output-feedback controllers for a class of vehicle suspension systems is presented. A theoretical background on recent advances in output-feedback control is first provided, which makes possible an effective synthesis of static output-feedback controllers by solving a single linear matrix inequality optimization problem. Next, a simplified model of a quarter-car suspension system is proposed, taking the ride comfort, suspension stroke, road holding ability, and control effort as the main performance criteria in the vehicle suspension design. The new approach is then used to design a static output-feedbackH∞controller that only uses the suspensi…
Direkte Dickenmessung an Muskelstreifenpräparaten und Gewebsschnitten
1967
An apparatus for direct measurement of the thickness of tissue slices and muscle strips is described. Micrometer callipers are used, the proper adjustment of which is indicated by the sudden scale deflection of an ohmmeter. In comparison with the method of calculation based on a measurement of the area of the slice, this technique is time-saving and the results are more accurate and reproducible.
Engineering the dynamics of topological spin textures by anisotropic spin-orbit torques
2020
Integrating topologically stabilized magnetic textures such as skyrmions as nanoscale information carriers into future technologies requires the reliable control by electric currents. Here, we uncover that the relevant skyrmion Hall effect, which describes the deflection of moving skyrmions from the current flow direction, acquires important corrections owing to anisotropic spin-orbit torques that alter the dynamics of topological spin structures. Thereby, we propose a viable means for manipulating the current-induced motion of skyrmions and antiskyrmions. Based on these insights, we demonstrate by first-principles calculations and symmetry arguments that the motion of spin textures can be …
Beamline pulsing system for cyclotrons
1998
Abstract A beamline pulsing system for cyclotrons is presented. The function of this system is to modify the structure of a cyclotron ion beam guided to the desired research target by a beamline. In some in-beam experiments, an adjustment of the time structure of the beam is sometimes needed. This kind of situation occurs if, for example, the life time of the target material is longer than the period corresponding to the beam frequency. In this case, the frequency of the ion pulses hitting the target is 10–21 MHz depending on the frequency of the acceleration voltage. The adjustment of the ion beam pulse frequency is carried out by a beamline deflector. Deflection is achieved by feeding a h…
Antihyperon potentials in nuclei via exclusive antiproton–nucleus reactions
2015
Abstract The exclusive production of hyperon–antihyperon pairs close to their production threshold in p ‾ -nucleus collisions offers a unique and hitherto unexplored opportunity to elucidate the behavior of antihyperons in nuclei. For the first time we analyze these reactions in a microscopic transport model using the Giesen Boltzmann–Uehling–Uhlenbeck transport model. The calculation takes the delicate interplay between the strong absorption of antihyperons, their rescattering and mean field deflection as well as the Fermi motion of the struck nucleon into account. We find a substantial sensitivity of transverse momentum correlations of coincident Λ ‾ Λ -pairs to the assumed depth of the Λ…
The non dissipative damping of the Rabi oscillations as a "which-path" information
2005
Rabi oscillations may be viewed as an interference phenomenon due to a coherent superposition of different quantum paths, like in the Young's two-slit experiment. The inclusion of the atomic external variables causes a non dissipative damping of the Rabi oscillations. More generally, the atomic translational dynamics induces damping in the correlation functions which describe non classical behaviors of the field and internal atomic variables, leading to the separability of these two subsystems. We discuss on the possibility of interpreting this intrinsic decoherence as a "which-way" information effect and we apply to this case a quantitative analysis of the complementarity relation as intro…
Quantum erasure within the optical Stern-Gerlach model
2005
In the optical Stern-Gerlach effect the two branches in which the incoming atomic packet splits up can display interference pattern outside the cavity when a field measurement is made which erases the which-way information on the quantum paths the system can follow. On the contrary, the mere possibility to acquire this information causes a decoherence effect which cancels out the interference pattern. A phase space analysis is also carried out to investigate on the negativity of the Wigner function and on the connection between its covariance matrix and the distinguishability of the quantum paths.