Search results for "POWER"
showing 10 items of 5099 documents
Semiactive vibration control of offshore wind turbine towers with tuned liquid column dampers using H<inf>&#x221E;</inf> output feedb…
2010
This short paper addresses the problem of vibration in wind turbine towers. These structures are subject to winds and waves causing undesirable vibrations that affect the structure integrity and system performance. In order to mitigate the vibrations of the tower, a controllable tuned liquid column damper is placed on its top. We propose the use of H ∞ control techniques to formulate a control law. Furthermore, the controller uses output feedback to avoid the dependence on the knowledge of the states of the system. Simulation results illustrate the design procedure proposed in this paper.
“These Dead Are Not Ours”: Identity Factors, Communicative Aspects and Regulative Meanings of Violence inside Cosa Nostra
2019
Il saggio analizza l’uso e il significato della violenza in Cosa Nostra dentro un quadro teorico più ampio che consente di coglierne le cornici concettuali e le ricche declinazioni fenomenologiche. Partendo dagli studi dei costruttivisti e dei post-strutturalisti, pone al centro della riflessione il rapporto tra violenza e potere (Weber, Popitz, Arendt), il tema della legittimazione discorsiva della violenza (Benjamin, Derrida), il suo legame con la corporeità (la biopolitica, di cui parla Foucault) e il suo radicamento nella sfera del simbolico e dello “spazio sociale” (Bourdieu), la dimensione speculare e “spettacolare” della violenza esibita (Ruggiero). Elementi che trovano ampio riscont…
Novel Configuration for a C-Band Axial Vircator With High Output Power
2022
We present a novel configuration for an axial virtual cathode oscillator (Vircator) operating in the C-band and designed for high output power applications. In order to enhance the efficiency, we have employed a geometry with up to seven reflectors along the drift space. While in previous research works this optimization process has been performed only varying the reflectors radii while using a fixed distance between reflectors,in our work we propose an optimization in terms of both reflectors radii and distances. Our optimized structure for the axial Vircator is able to provide an efficiency up to 15.6% and an output power of 1.6 GW in the C-band, with a working voltage of 510 kV and a cat…
Hvordan bør menigheter arbeide med endring? En drøfting av relevansen av organisasjonsteoretiske perspektiver for endringstiltak i menigheter
2016
How ahould congregations work with change? A discussion of the relevance of organizational theoretical perspectives for change in congregations The purpose of this article is to discuss the contribution to congregations of theoretical perspectives on change in the organizational literature. The contribution of the discussion is on the evaluation of the relevance. I discuss the relevance of planned change, lifecycle theory, external influences, power, and coincidence and conclude that organizational perspectives are relevant as long as they applies in a context sensitive manner. I suggests a bounded rational planning process for congregational development. The arguments for this is that cong…
Visual acuity with computer simulated and lens-induced astigmatism
2014
[EN] The relationship between spherical and astigmatic refractive errors and their associated visual acuity is investigated in this work by means of two different approaches. In the first one, different refractive errors were induced in normal subjects by trial lenses. In the second one, defocused images were simulated numerically by the optical transfer function of a model eye and then judged by the same subjects. The amount of defocus (measured in terms of the modulus of the dioptric power vector) necessary to reduce the visual acuity to 0.1 logMAR and to 0.4 logMAR was computed with each method and then compared. We found that the visual system is clearly more tolerant to lens-induced de…
Discovering the Discriminating Power in Patient Test Features Using Visual Analytics: A Case Study in Parkinson’s Disease
2016
Part 11: New Methods and Tools for Big Data Wokshop (MT4BD); International audience; This paper presents a novel methodology for selecting the most representative features for identifying the presence of the Parkinson’s Disease (PD). The proposed methodology is based on interactive visual analytic based on multi-objective optimisation. The implemented tool processes and visualises the information extracted via performing a typical line-tracking test using a tablet device. Such output information includes several modalities, such as position, velocity, dynamics, etc. Preliminary results depict that the implemented visual analytics technique has a very high potential in discriminating the PD …
Anne d’Autriche en ses images : légitimation du pouvoir féminin et culture visuelle de la majesté dans la France du XVIIe siècle
2018
Anne of Austria offers an important part, yet neglected, in the the development of royal iconography in seventeenth century France. Devoided from management of power under the reign of her husband Louis XIII, she is however the subject of many representations. The number of her images increases when she accedes to the responsibilities of the government at the death of the king, in 1643, becoming regent in the name of her minor son, Louis XIV. Beyond its majority in 1651, she maintains herself at a prominent place, until the death of Mazarin in 1661. During these two decades, a deep political crisis in France culminates in the so-called Fronde. In this context, the image of Anne of Austria b…
Multivariate EEG spectral analysis evidences the functional link between motor and visual cortex during integrative sensorimotor tasks
2012
The identification of the networks connecting brain areas and the understanding of their role in executing complex tasks is a crucial issue in cognitive neuroscience. In this study, specific visuomotor tasks were devised to reveal the functional network underlying the cooperation process between visual and motor regions. Electroencephalography (EEG) data were recorded from twelve healthy subjects during a combined visuomotor task, which integrated precise grip motor commands with sensory visual feedback (VM). This condition was compared with control tasks involving pure motor action (M), pure visual perception (V) and visuomotor performance without feedback (V + M). Multivariate parametric …
Studying brain visuo-tactile integration through cross-spectral analysis of human MEG recordings
2010
An important aim in cognitive neuroscience is to identify the networks connecting different brain areas and their role in executing complex tasks. In this study, visuo-tactile tasks were employed to assess the functional correlation underlying the cooperation process between visual and tactile regions. MEG data were recorded from eight healthy subjects while performing a visual, a tactile, and a visuo-tactile task. To define regions of interest (ROIs), event-related fields (ERFs) were estimated from MEG data related to visual and tactile areas. The ten channels with the highest increase in ERF variance, moving from rest to task, were selected. Cross-spectral analysis was then performed to a…
Reliability of PEA Measurement in Presence of an Air Void Defect
2020
This paper deals with the reliability of the Pulsed Electro-Acoustic (PEA) technique in the case of a specimen containing an air layer. The first approach to this study has been proposed by the authors in previously published works. In these papers, the mathematical description, the PEA cell simulation model, and some experimental tests have been reported. In this work, a more accurate description of the acoustic wave behavior within the PEA cell and specimen with and without an air layer is given. Moreover, the comparison between simulation and experimental tests for both cases (specimen with and without air layer) allowed the validation of the previously developed PEA cell simulation mode…