15 papers · ranked by Valyu relevance
Robert A. Van Gorder
We describe how to control the motion – both speed and propagation direction – of a nonlinear traveling wave in real time via soliton management with time-varying dispersion/diffusion and loss/gain terms. When carried out subject to certain parameter constraints we derive, the approach allows for real-time manipulation…
Sebastiano Cominelli, Carlo Sinigaglia, Davide Enrico Quadrelli, Francesco Braghin
'Francesco Braghin'] In this paper, we propose a novel approach for controlling surface water waves and their interaction with floating bodies. We consider a floating target rigid body surrounded by a control region where we design three control strategies of increasing complexity: an active strategy based on…
Mattia Raffero, Michele Martini, Biagio Passione, Giuliana Mattiazzo + 2 more
'Ermanno Giorcelli' 'Giovanni Bracco'] The ISWEC (inertial sea wave energy converter) is presented, its control problems are stated, and an optimal control strategy is introduced. As the aim of the device is energy conversion, the mean absorbed power by ISWEC is calculated for a plane 2D irregular sea state. The…
Rupamanjari Majumder, Iolanda Feola, Alexander S. Teplenin, Antoine A. F. de Vries + 2 more
Propagation of non-linear waves is key to the functioning of diverse biological systems. Such waves can organize into spirals, rotating around a core, whose properties determine the overall wave dynamics. Theoretically, manipulation of a spiral wave core should lead to full spatiotemporal control over its dynamics.…
Mertcan Yetkin, Sudharsan Kalidoss, Frank E. Curtis, Lawrence Snyder + 1 more
'Arindam Banerjee'] A generic formulation for the optimal control of a single wave-energy converter (WEC) is proposed. The formulation involves hard and soft constraints on the motion of the WEC to promote reduced damage and fatigue to the device during operation. Most of the WEC control literature ignores the cost of…
Pedro Fornaro, Jacopo Ramello, Facundo Daniel Mosquera, Giuseppe Giorgi + 1 more
This article presents a detailed description, and step-by-step process, required to build a small-scale wave energy tank demonstrator (Tiny-T). The system consists of an operative wave energy converter (WEC) with active control, representing the first demonstration of electronic WEC control at 1/100 scale. A key…
Darío Pighin, Enrique Zuazua
We consider both the internal and boundary controllability problems for wave equations under non-negativity constraints on the controls. First, we prove the steady state controllability property with nonnegative controls for a general class of wave equations with time-independent coefficients. According to it, the…
Diego B. S. Audiffred, André V. G. Cavalieri, Pedro P. C. Brito, Eduardo Martini
'Eduardo Martini'] Reactive flow control has been shown as a promising tool to improve, among other aspects, the aerodynamic characteristics of an aircraft. This paper focuses on the use of reactive flow control to attenuate Tollmien-Schlichting (TS) waves over a wing profile. TS waves are an instability mechanism that…
Yunzhong Wang, Damian Tohl, Anh Tran Tam Pham, Youhong Tang + 2 more
'Qiongfeng Shi' 'Najib Kacem'] The development of low-frequency and low-amplitude wave energy harvesters has been limited by the lack of an affordable scientific evaluation platform, due to the high cost and land requirements of ground-based water channels. A 3D-printed modular wave generator, combined with the…
Yulei Liao, Leifeng Wang, Yiming Li, Ye Li + 2 more
'Houbing Song'] The control system designing of Unmanned Wave Glider (UWG) is challenging since the control system is weak maneuvering, large time-lag and large disturbance, which is difficult to establish accurate mathematical model. Meanwhile, to complete marine environment monitoring in long time scale and large…
Diego B. S. Audiffred, André V. G. Cavalieri, Igor A. Maia, Eduardo Martini + 1 more
'Eduardo Martini' 'Peter Jordan'] We present an experimental study of reactive control of turbulent jets. We target axisymmetric disturbances associated with coherent structures, which are known to underpin the peak sound radiation of turbulent jets. We first consider a forced jet flow case, such that the coherent…
X. Mao
The adjoint-based sensitivity analyses well explored in hydrodynamic stability studies are extended to calculate the sensitivity of forces acting on an aerofoil with respect to wall transpiration. The magnitude of the sensitivity quantifies the controllability of the force, and the distribution of the sensitivity…
Authors not listed
The present study investigates the transient 3D numerical prediction of the significance of passive control techniques, using triangular and rectangular span-wise pimples, placed at cambered section at the location 32% chord length from of the nose of the hydrofoil, and combined with a modified finite trailing edge…
Marshall J. Colville, Sangwoo Park, Warren R. Zipfel, Matthew J. Paszek
Recent advances in fluorescence microscopy have enabled the visualization of subcellular structures at unprecedented resolution. However, the complexity of state-of-the-art microscopes has increased considerably, often requiring the precise control and synchronization of multiple peripheral devices at high speeds.…
Sayak Bhattacharya, Scott L. Brincat, Mikael Lundqvist, Earl K. Miller
Neural oscillations are evident across cortex but their spatial structure is not well-explored. Are oscillations stationary or do they form “traveling waves”, i.e., spatially organized patterns whose peaks and troughs move sequentially across cortex? Here, we show that oscillations in the prefrontal cortex (PFC)…