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Said F.,University of Tromso | Johnsen H.,Northern Research Institute Tromso
IEEE Transactions on Geoscience and Remote Sensing | Year: 2014

An alternative approach to sea surface wind retrieval using synthetic aperture radar (SAR) stripmap (SM) data is explored in this paper, using both the polarization residual Doppler frequency (PRDF) - the difference between the VV and HH Doppler centroids - and the normalized radar cross section (NRCS). The PRDF not only enables the possible elimination of unwanted biases present in both VV and HH Doppler estimates but also helps decrease the number of wind ambiguities down to two. In order to successfully infer the wind field from the PRDF, the use of a geophysical Doppler model function, such as the general curvature model (GCM)-Dop, is necessary. Using such a function, a simulated version of the PRDF at X-band is analyzed in terms of the sea surface wind field at various incidence angles. Simulations first show that the PRDF increases with increasing incidence angle regardless of wind field conditions. Actual PRDF measurements also exhibit strong correlation with radial components of the wind speed. An alternate SAR wind retrieval procedure, incorporating both the PRDF and the NRCS, is tested on a series of dual-polarized SM TerraSAR-X scenes carefully selected along the Norwegian coast. The geophysical model functions used for this analysis are the GCM-NRCS and GCM-Dop. A 1.13-m/s bias, with a correlation of 0.85 and a 1.86-m/s rmse, exists between the mean estimated wind speeds and in situ measurements, while a 15.43° bias, with a 0.93 correlation coefficient and a 34.1° rmse, is found between the mean estimated wind directions and in situ measurements. © 2013 IEEE. Source


Krause G.,Alfred Wegener Institute for Polar and Marine Research | Brugere C.,University of York | Diedrich A.,SOCIB | Diedrich A.,James Cook University | And 8 more authors.
Aquaculture | Year: 2015

Failure of the blue revolution is a global risk. The international problem is that there is a gap in knowledge exchange between the aquaculture industry, policy makers trying to support aquaculture development and people who depend on aquaculture for a job and/or food source. Thus, governments and international organizations promoting aquaculture as the solution to improving food security, nutrition and income are failing to optimise production of natural aquatic resources.We identify a "people-policy gap", and suggest that this is an understudied constraint, which needs to be overcome before worldwide food security can be achieved from aquatic environments. We argue that this gap leads to uneven distribution of benefits, a disconnection between benefits and local needs, and detrimental effects on human health and food security, all of which can have negative repercussions on human communities and ecosystems. In order to address this need, we present an analytical framework to guide context specific, policy-relevant assessments of the social, economic and ecological dimensions of aquaculture on a case-by-case basis. The framework is designed to make best use of existing data and scientific tools for decision-making.In conclusion, we argue for: equal consideration of ecological, social and economic issues in aquaculture policy-making; pre-emptive identification of likely social impacts; integration of people- and context-specific social framing conditions into planning and policy review; addressing the social disconnection between global consumption and production; and, encouragement of creative combinations of theories and methods to assess and interpret the social dimensions of aquaculture in multiple contexts. © 2015 Elsevier B.V. Source


Fernandez-Luque L.,Northern Research Institute Tromso
Conference proceedings : ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference | Year: 2010

Health consumers have embraced the web to obtain access to health information and to socialize and share knowledge with peers. Additionally, the web has become a more interactive and rich platform with the integration of health applications and services, such as Personal Health Records. Some of these applications provide personalized interactions based on user specific characteristics. In this paper we provide an overview of Personalized Health Applications in the Web 2.0. We reviewed the health applications integrated in Google Health, Microsoft HealthVault and Facebook. We studied the goals of the applications and also the personalized feedback they provided. Source


Isham B.,Interamerican University of Puerto Rico | Rietveld M.T.,European Incoherent Scatter Scientific Association | Guio P.,University College London | Forme F.R.E.,CNRS Institute for research in astrophysics and planetology | And 2 more authors.
Physical Review Letters | Year: 2012

Langmuir cavitons have been artificially produced in Earth's ionosphere, but evidence of naturally occurring cavitation has been elusive. By measuring and modeling the spectra of electrostatic plasma modes, we show that natural cavitating, or strong, Langmuir turbulence does occur in the ionosphere, via a process in which a beam of auroral electrons drives Langmuir waves, which in turn produce cascading Langmuir and ion-acoustic excitations and cavitating Langmuir turbulence. The data presented here are the first direct evidence of cavitating Langmuir turbulence occurring naturally in any space or astrophysical plasma. © 2012 American Physical Society. Source


Cascado D.,University of Seville | Romero S.J.,University of Seville | Hors S.,University of Seville | Brasero A.,University of Seville | And 2 more authors.
2010 Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBC'10 | Year: 2010

In this paper we discuss about the integration of Ambient-Assisted Living (AAL) with virtual worlds. The integration of sensors from the AAL environment (e.g. vital signs, motion sensors) in the Virtual World can enhance the provision of in-world eHealth services, such as telerehabilitation, and taking advance of the social nature of virtual worlds. An implementation of a virtual world integrated in an AAL environment for tele-rehabilitation is described in this paper. At this time, all of the system's modules have been developed and we are currently integrating them in a fully functional version. The system will be tested with real users during 2010 in the Sport Medical Unit of The University of Seville. This paper describes the architecture and functionalities of the system. © 2010 IEEE. Source

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