Search results for " Buoy"
showing 10 items of 13 documents
Wave energy assessment in Sicily (Italy)
2015
Abstract This research presents an estimation of wave energy potential in Sicily (Italy) carried out using both buoy wave measurements from Rete Ondametrica Nazionale (RON), the Italian Government wave buoy network, and wave parameter data by ERA-INTERIM, a recent meteorological reanalysis project of the European Centre for Medium-Range Weather Forecasts (ECMWF). Starting from these offshore data, we first identified the western part of Sicily as the area with a higher availability of offshore wave energy; subsequently, we selected a study area in the western part of the south coast and assessed the nearshore potential energy by performing propagation using a spectral model (SWAN). The near…
Energy assessment of a wave energy converter in a small island. A case study
2022
The diffusion of technologies supplied by Renewable Energy Sources (RES) is contributing to the challenge of reduction of energy dependence from fossil fuels, avoiding the emission of several polluting substances and greenhouse gases (GHG). Already today, global warming caused by human activity is estimated at around 1∘C; energy consumption attributable to human habits is no longer sustainable. To date, energy production is still heavily dependent on fossil fuels. To reverse the negative trend, it is necessary to invest in new technologies and improve the efficiency of energy production plants in general. In particular, a wave energy converter will be presented, consisting of a buoy connect…
Reducing Stress and Enhancing Academic Buoyancy among Adolescents Using a Brief Web-based Program Based on Acceptance and Commitment Therapy : A Rand…
2018
Acceptance and commitment therapy programs have rarely been used as preventive tools for alleviating stress and enhancing coping skills among adolescents. This randomized controlled trial examined the efficacy of a novel Finnish web- and mobile-delivered five-week intervention program called Youth COMPASS among a general sample of ninth-grade adolescents (n= 249, 49% females). The intervention group showed a small but significant decrease in overall stress (between-group Cohen’s d = 0.22) and an increase in academic buoyancy (d= 0.27). Academic skills did not influence the intervention gains, but the intervention gains were largest among high-stressed participants. The results suggest that …
On the influence of gravitational and centrifugal buoyancy on laminar flow and heat transfer in curved pipes and coils
2015
Abstract The effects of gravitational and centrifugal buoyancy on laminar flow and heat transfer in curved and helical pipes were investigated by numerical simulation. Six dimensionless numbers characterizing the problem were identified, and an analysis was conducted on the possible combinations of signs of the gravitational and centrifugal buoyancy effects. Two distinct Richardson numbers were introduced in order to quantify the importance of the two types of buoyancy, and it was shown that, in the case of heating from the wall, a maximum realizable value of the centrifugal Richardson number exists which is a linear function of the curvature δ (ratio of pipe radius a to curvature radius c)…
Design and experimental test of a low costweather buoy
2013
The importance of prevention plans based on realistic inundation scenarios was dramatically highlighted by the Indian Ocean Tsunami of 26 December 2004. But also in the Mediterranean, sea storms basin are a quite common event especially during winter months. These scenarios are generally based on numerical models of tsunami wave propagation that can become more realistic and effective when calibrated with the distribution of true data acquired by special weather buoy. In this paper we present the result of an experimental weather buoy built by DEIM of University of Palermo, that is characterized by small cost and big versatility.
A GENERAL COMPUTATIONAL APPROACH FOR MAGNETOHYDRODYNAMIC FLOWS USING THE CFX CODE: BUOYANT FLOW THROUGH A VERTICAL SQUARE CHANNEL
2000
The buoyancy-driven magnetoconvection in the cross section of an infinitely long vertical square duct is investigated numerically using the CFX code package. The implementation of a magnetohydrodynamic (MHD) problem in CFX is discussed, with particular reference to the Lorentz forces and the electric potential boundary conditions for arbitrary electrical conductivity of the walls. The method proposed is general and applies to arbitrary geometries with an arbitrary orientation of the magnetic field. Results for fully developed flow under various thermal boundary conditions are compared with asymptotic analytical solutions. The comparison shows that the asymptotic analysis is confirmed for hi…
The “Seili-index” For The Prediction of Chlorophyll-α Levels In The Archipelago Sea of The Northern Baltic Sea, Southwest Finland
2021
AbstractTo build a forecasting tool for the state of eutrophication in the Archipelago Sea, we fitted a Generalized Additive Mixed Model (GAMM) to marine environmental monitoring data, which were collected over the years 2011–2019 by an automated profiling buoy at the Seili ODAS-station. The resulting “Seili-index” can be used to predict the chlorophyll-α (chl-a) concentration in the seawater a number of days ahead by using the temperature forecast as a covariate. An array of test predictions with two separate models on the 2019 data set showed that the index is adept at predicting the amount of chl-a especially in the upper water layer. The visualization with 10 days of chl-a level predict…
A security and surveillance application of the innovative Monitoring Underwater Buoy Systems (MUnBuS) on the Protected Marine Area (AMP) of capo gall…
2015
The proposed low cost systems shows the results obtained in the implementation and testing on real security application to Protected Marine Area surface and submarine environment of a innovative Monitoring Underwater Buoy Systems (MUnBuS) for installation with IR-CCTV-Cam, ultrasonic dolphin warning system and Green Laser Perimeter Detection. This concerning innovative Monitoring Underwater Buoy Systems that can be remotely controlled from the ground, air, satellite and sea and from a Center of Supervision Telecontroller And Data Acquisition and Monitoring (Mobile- STADAM Center). The Buoy is hosts for the radio or satellite communication equipment, the downloading and telemetering data equ…
Bench-scale investigation of inclined dense jets
2005
In this work experimental data on the geometry of dense inclined jets issuing in a lab-scale glass rectangular tank are presented. The surrounding fluid was always tap water at room temperature while the dense jets were water solutions of NaCl. Four parameters were changed in the experiments, namely nozzle diameter and inclination, and jet density and flow rate. Jet trajectories were revealed by a colored tracer. Images of the jet were recorded by a digital camera and then further digitally processed, eventually resulting in a time-averaged tracer intensity field. All the jet geometrical parameters, once normalized, were found to be very well correlated to the densimetric Froude number. Mod…
School-related stress among sixth-grade students : Associations with academic buoyancy and temperament
2019
The present study examined to what extent sixth-grade students' academic buoyancy and temperament contributed to their school-related stress. A total of 845 students rated their school-related stress at the beginning and end of the school year and their academic buoyancy at the beginning of the year. Parents rated students' effortful control and negative affectivity. The results showed that high academic buoyancy, high effortful control, and low negative affectivity at the beginning of the school year were related to lower school-related stress at the end of the school year, after controlling for gender, GPA, and previous level of stress. Effortful control and negative affectivity had no si…