|
|
|
|
|
Houliez, Emilie; Lefebvre, Sebastien; Lizon, Fabrice; Schmitt, Francois G.. |
This study is the first in situ work comparing rapid light curves (RLC) and non-sequential steady-state light curves (N-SSLC) in their efficiency to characterize phytoplankton photosynthetic activity and acclimation status. Measurements were carried out at two time scales (daily and annual) using the Pulse Amplitude Modulated fluorometry on samples taken in the coastal waters of a macrotidal ecosystem (the Strait of Dover, eastern English Channel). RLC and N-SSLC were compared under a wide range of environmental conditions and phytoplankton composition in order to define the best methodology to accurately capture short and long-term adjustments in the functioning of the photosynthetic apparatus. The relationships between the photosynthetic parameters... |
Tipo: Text |
|
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00395/50596/51484.pdf |
| |
|
|
Medina, Olmo Duran; Schmitt, Francois G.; Calif, Rudy; Germain, Gregory; Gaurier, Benoit. |
The correlation between the flow turbulence and the performances of a marine current turbine is studied. First, the incoming flow encountered in the flume tank is characterized in the framework of fully developed turbulent cascades in the inertial range. The Reynolds number, the Kolmogorov dissipation scale and the integral scale, are estimated from flow measurements. The intermittency of the turbulence is characterized in the lognormal multifractal framework, and the influence of the turbulent flow on the turbine power is assessed. The rotor speed control unit characteristics used for the turbine regulation induces non-negligible effects on the turbine behavior under fluctuations loads. Even if the power spectrum does not reveal any scale invariance, a... |
Tipo: Text |
Palavras-chave: Marine energy; Turbulence; Multifractal energy cascade; Intermittency; Turbine power production; High frequency data rate. |
Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00385/49620/50134.pdf |
| |
|
| |
|
|
|