Oceans of Tomorrow sensor interoperability for in-situ ocean monitoring

The Oceans of Tomorrow (OoT) projects, funded by the European Commission’s FP7 program, are developing a new generation of sensors supporting physical, biogeochemical and biological oceanographic monitoring. The sensors range from acoustic to optical fluorometers to labs on a chip. The result is that the outputs are diverse in a variety of formats and communication methodologies. The interfaces with platforms such as floats, gliders and cable observatories are each different. Thus, sensorPeer ReviewedPostprint (author's final draft

Enseñar y aprender cálculo con ayuda de la vista gráfica 3D de GeoGebra

En este artículo se esbozan los fundamentos teóricos que sustentan la utilización de la vista gráfica 3D de GeoGebra como herramienta para la enseñanza y el aprendizaje del Cálculo Diferencial e Integral. También se comparten algunas ideas, a modo de ejemplo, de construcciones que pueden realizarse para ayudar a comprender algunos conceptos que suelen resultar difíciles para los alumnos, debido a la gran dificultad de representarlos gráficamente utilizando sólo lápiz y papel, obligando al estudiante a limitarse a su manipulación algebraica. Los ejemplos abordados se relacionan con los temas: sólidos de revolución, extremos relativos en funciones de dos variables y cálculo de límites en funciones de dos variables

Seeking to enhance the bioenergy of municipal sludge: Effect of alkali pre-treatment and soluble organic matter supplementation

The aim of this research is to enhance the mesophilic anaerobic digestion of municipal sludge from Cadiz-San Fernando (Spain) wastewater treatment plant at 20 days hydraulic retention time (HRT). Two different strategies were tested to improve the process: co-digestion with the addition of soluble organic matter (1% v/v); and alkali sludge pre-treatment (NaOH) prior to co-digestion with glycerine (1% v/v). Methane production (MP) was substantially enhanced (from 0.36 ± 0.09 L CH4 l/d to 0.85 ± 0.16 L CH4 l/d), as was specific methane production (SMP) (from 0.20 ± 0.05 L CH4/g VS to 0.49 ± 0.09 L CH4/g VS) when glycerine was added. The addition of glycerine does not seem to affect sludge stability, the quality of the effluent in terms of pH and organic matter content, i.e. volatile fatty acids (VFA), soluble organic matter and total volatile solid, or process stability (VFA/Alkalinity ratio < 0.4). Alkali pre-treatment prior to co-digestion resulted in a high increase in soluble organic loading rates (more than 20%) and acidification yield (more than 50%). At 20 days HRT, however, it led to overload of the system and total destabilization of the mesophilic anaerobic co-digestion of sewage sludge and glycerine

Mesophilic anaerobic co-digestion of sewage sludge with glycerine: Effect of solids retention time

The main objective of this paper is to examine the effect of the increase in organic loading rates (OLRs), by reducing the solids retention time (SRT) from 20 d to 5 d, in single-phase mesophilic anaerobic co-digestion of sewage sludge with glycerine (1% v/v). It was experimentally confirmed that anaerobic co-digestion of these biowastes under steady-state conditions can achieve an 85 ± 5% reduction in volatile fatty acids (VFA) at SRTs of between 20 and 9 d, with a methane production yield of around 0.8 l CH4/l/d. Decreases in the SRT not only allow the sludge stability and biogas production to be maintained, but also lead to an increase in the waste that could be treated and lower operating costs. Therefore, mesophilic anaerobic co-digestion of sewage sludge and glycerin at a SRT lower than 20 d is possible and preferable due to being more economical and environmentally friendl

Optical fibers to measure temperature vertical profile at sea

The paper is focus in the use the optical fiber to measure the temperature in various heigh at the same time to get a temperature vertical variation. The temperature measurements are puntual while the Bragg gratings located in the fiber.Peer Reviewe

Multilayer hazes over Saturn’s hexagon from Cassini ISS limb images

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Some Aspects of the Thorny Skate (Raja radiata Donovan, 1808) Reproductive Biology in NAFO Division 3N Regulatory Area

Thorny skate samples from August to December 2000 were examined to determine both sexes maturity stages, length at maturity and females potential fecundity. The size and number of the ovarian oocytes increase as the maturation progress. In fully mature ovaries the average number of developed eggs is between 40 and 45 and its final mean size is 12.5 mm. The minimum number of developing eggs per female found in the ovaries was 2 and the maximum 88. Very few females at either the capsule extrusion or other of the active uterine stages have been found. On the contrary most part of the adult males were at the fully mature stages, suggesting that the samples could be taken on a mating aggregation season. Using data from 1997, 1999 and 2000, both maturity ogives have been fitted. The females length at maturity obtained ranged between 60 and 54 cm and that of the males between 43 and 51 cm

Seasonality and reproductive parameters of the thorny skate (Raja radiata Donovan, 1808) in NAFO Division 3N

In this paper the seasonal and geographic pattern of the fishing effort distribution targeting thorny skate is described. The fishery is performed in fall and in a quite restricted area of Div. 3N, in shallow waters of less than 100 m. The results support that the fishery is largely based on a skate mating concentration. The estimated length at 50 % maturity in males and females is 51 and 55 cm respectively

Spanish Skate (Raja radiata Donovan, 1808) Fishery in the Grand Bank (NAFO Division 3N): 1997-2000.

The Spanish skate fishery in NAFO Regulatory Area is performed from August to November in a quite restricted area of Div. 3N at depths between 51 and 100 m. Fishing effort, unstandardized catch rates, length composition, sexual maturity, by-catch, discards and sex-ratios are presented in this paper. The length range of thorny skate in the catches is mainly between 30 and 85 cm, with a mode of 50-51 cm. Both sexes appeared equally represented in the catches. The main by-catch in this fishery is American plaice and yellowtail flounder. A large proportion of mature males are observed