Search results for "FSH"

Numerical and analytical analysis of a monopile-supported offshore wind turbine under ship impacts

2021

Abstract Offshore wind turbines in the vicinity of ship traffic are exposed to increased risks of ship collisions. To better understand the impact mechanism, this paper evaluates the dynamic responses of a monopile-supported wind turbine under ship impacts, using both numerical and analytical methods. The nonlinear finite element method is applied during the numerical simulations, and the wind load effects, soil conditions, and rigid and deformable ship bows are considered. The analytical approach, originally developed based on the energy method, is extended here to address the damping effects of monopile-supported wind turbines. In the case study, the impacts are studied between a 4600-ton…

Offshore wind metadata management

2014

Offshore wind energy is gaining more and more attention from industry and research community due to its high potential in producing green energy and lowering price on electricity consumption. However, offshore wind is facing many challenges, and hence it is still expensive to install in large scale. It therefore needs to be considered from different aspects of technologies in order to overcome these challenges. One of the problems of the offshore wind is that information comes from different sources with diversity in types and format. Besides, there are existing wind databases that should be utilised in order to enrich the knowledge base of the wind domain. This paper describes an approach …

A comparative study on the dynamic response of three semisubmersible floating offshore wind turbines

2019

Abstract Currently, there is a great interest to globally develop offshore wind energy due to the greenhouse effect and energy crisis. Great efforts have been devoted to develop reliable floating offshore wind energy technology to exploit the wind energy resources in deep seas. This paper presents a comparative study of the dynamic response of three different semisubmersible floating wind turbine structures. All the three platforms support the same 5MW wind turbine. The platforms examined are: a V-shaped Semi, an OC4-DeepCwind Semi and a Braceless Semi at 200 m water depth. A dynamic analysis is carried out in order to calculate and compare the performance of these platforms. The comparison…

Active heave compensation of floating wind turbine installation using a catamaran construction vessel

2021

Abstract The application of floating wind turbines is limited by the high cost that increases with the water depth. Offshore installation and maintenance continue to consume a high percentage of the project budget. To improve the installation efficiency of the floating offshore wind turbine, a novel concept is proposed by the SFI MOVE project. Several wind turbine superstructure components are preassembled onshore and carried to the installation site by a catamaran construction vessel. Each assembly can then be installed using only one lift, and the concept is less sensitive to weather conditions. In this paper, a control algorithm of the proposed hydraulic active heave compensator system i…

Les interactiones de Casimir hors d'équilibre : effets dynamiques et thermiques

2016

In this thesis, after an introduction where we briefly present the general context of Casimir physics, we present the results obtained during the PhD. At first, we show our work about the van der Waals/Casimir-Polder interactions between two atoms in an out-of-equilibrium condition due to their uniformly accelerated motion. We study the system of two uniformly accelerated atoms in vacuum space, when they are in their ground-state and when they are in a correlated state (one excited and one ground-state atom). We analyze this system both with an heuristic semiclassical model and with a more rigorous method, based on a separation of radiation reaction and vacuum fluctuations contributions, th…

Further Results on Modeling, Analysis, and Control Synthesis for Offshore Wind Turbine Systems

2014

Renewable energy is a hot topic all over the world. Nowadays, there are several sustainable renewable power solutions out there; hydro, wind, solar, wave, and biomass to name a few. Most countries have a tendency to want to become greener. In the past, all new wind parks were installed onshore. During the last decade, more and more wind parks were installed offshore, in shallow water. This chapter investigates a comparative study on the modeling, analysis, and control synthesis for the offshore wind turbine systems. More specifically, an \( {\mathcal{H}}_{\infty } \) static output-feedback control design with constrained information is designed. Constrained information indicates that a rema…

Elementi di pericolosità geologica dell’offshore del margine calabro-ionico

2008

Piattaforme oil and gas e sviluppo turistico: evidenze da una analisi esplorativa sull’accettabilità del decommissioning circolare

2022

Lo studio propone una lettura dell’accettabilità sociale del decommissioning circolare delle piattaforme oil and gas a fini di sviluppo turistico con una particolare attenzione alle installazioni presenti in Italia. Esso mostra come: 1) il pubblico riconosca un certo potenziale di riutilizzo turistico delle piattaforme; 2) l’accettabilità sociale sia ostacolata da distorsioni percettive; 3) la modifica di tali percezioni richiedano compiute policy di marketing sociale. This study focuses on the social acceptability of oil and gas platforms circular decommissioning and its potential for tourism development purposes, especially in Italy. It shows how: 1) the public acknowledges potential for …

Design and protocol of Estrogenic Regulation of Muscle Apoptosis (ERMA) study with 47 to 55-year-old women's cohort : novel results show menopause-re…

2018

Objective: The multidisciplinary Estrogenic Regulation of Muscle Apoptosis (ERMA) study was designed to reveal how hormonal differences over the menopausal stages affect the physiological and psychological functioning of middle-aged women. This paper describes the protocol and nonrespondent analysis of ERMA and novel findings on menopausal differences in blood count variables and their association with female sex hormones. Methods: Women aged 47 to 55 years were assigned to pre, early peri, late peri, and postmenopausal groups based on follicle-stimulating hormone (FSH) and bleeding diary. Multivariate linear regression models were constructed to estimate the association of 17b-estradiol (E…

FLUMO: FLexible Underwater MOdem

2019

The last years have seen a growing interest in underwater acoustic communications because of its applications in marine research, oceanography, marine commercial operations, the offshore oil industry and defense. High-speed communication in the underwater acoustic channel has been challenging because of limited bandwidth, extended multipath, refractive properties of the medium, severe fading, rapid time variation and large Doppler shifts. In this paper, we show an implementation of a flexible Software-Defined Acoustic (SDA) underwater modem, where modulation parameters are completely tunable to optimize performance. In particular, we develop the system architecture following two key ideas. …