Time filter

Source Type

de Vos B.I.,LEI Part of Wageningen UR | Doring R.,Johann Heinrich Von Thunen Institute | Aranda M.,Tecnalia | Buisman F.C.,LEI Part of Wageningen UR | And 7 more authors.
Marine Policy | Year: 2016

Fisheries policy is increasingly influenced by civil society organizations. The newest example of this is the formulation of the landing obligation, a regulation that should reduce the contested practice of discarding unwanted fish. In this paper the implementation process of the landing obligation in four European countries is compared. From this comparison it becomes clear that fishers are working on diminishing discards. However it also shows that for the legitimacy, and the effectiveness of policy it is not only vital to increase the influence of civil society actors, but also the participation of resource users. Their views, knowledge, and cooperation are vital for a successful implementation of the regulation. Otherwise, resistance become too high, and regulation becomes more symbolic than a tool for change. © 2015 Elsevier Ltd. Source

Basurko O.C.,AZTI Marine Research Division | Uriondo Z.,University of the Basque Country
Applied Thermal Engineering | Year: 2015

Condition-Based Maintenance for diesel engines has contributed to reliability, energy-efficiency, and cost reduction. Both, the modelling of engine performance and fault detection require large amounts of data; usually, these are obtained on a test bench. In contrast, in operative engines, provoking faults onboard is not a viable proposition. Condition-Based Maintenance, fault detection and diagnosis need to be solved on engines installed in commercial vessels: the present contribution answers this need. A medium-speed diesel engine was monitored using thermocouples, pressure sensors, a propeller shaft torque meter and fuel oil flow-meters, during more than 10,000 running hours. Monitored data were used to train a three-layer feed-forward neural network, to generate the engine performance model; thus, determine the engine's fuel consumption and faulty conditions. The faulty conditions considered were: (1) a polluted turbine; (2) a dirty air filter/compressor; (3) a dirty air cooler; (4) and bad fuel injection, i.e. bad combustion. The sensor's precision and the experience gained by monitoring the engine served as a baseline to define the fault threshold values. The results proved the feasibility of installing a Condition-Based Maintenance, for vessels in operation, by monitoring engine performance and analysing the data with the aid of artificial neural networks. © 2015 Elsevier Ltd. All rights reserved. Source

Belzunce-Segarra M.J.,AZTI Marine Research Division | Belzunce-Segarra M.J.,CSIRO | Simpson S.L.,CSIRO | Amato E.D.,CSIRO | And 5 more authors.
Environmental Pollution | Year: 2015

Laboratory-based bioaccumulation and toxicity bioassays are frequently used to predict the ecological risk of contaminated sediments in the field. This study investigates the bioassay conditions most relevant to achieving environmentally relevant field exposures. An identical series of metal-contaminated marine sediments were deployed in the field and laboratory over 31 days. Changes in metal concentrations and partitioning in both sediments and waters were used to interpret differences in metal exposure and bioaccumulation to the benthic bivalve Tellina deltoidalis. Loss of resuspended sediments and deposition of suspended particulate matter from the overlying water resulted in the concentrations of Cu, Pb and Zn (major contaminants) becoming lower in the 1-cm surface layer of field-deployed sediments. Lower exchange rates of overlying waters in the laboratory resulted in higher dissolved metal exposures. The prediction of metal bioaccumulation by the bivalves in field and laboratory was improved by considering the metal partitioning within the surface sediments. © 2015 Elsevier Ltd. Source

Discover hidden collaborations