Consulta: subjectFacets:"Coupling"
Registros recuperados: 8
Data/hora: 11/06/2024 06:42:43

Contribution à l'étude du couplage entre diffusion d'eau et contrainte mécaniques dans les matériaux marins hautes performances
Provedor de dados: 5
Autores: Humeau, Corentin.
The aim of the study was to understand the impact of coupling on water diffusion and mechanical stress on marine installations. Moreover, we identified the key phenomena involved during this type of exposure. When we look to these type of applications we can distinguish two type of materials used: one for the structure and another for mooring facilities. The best performing structural materials appear to be composites, while the most effective mooring devices are made with synthetic ropes. Therefore, we decided to investigate both materials with the same method: first the properties uncoupled, second, as semi-coupled behaviours and finally as one coupled phenomenon. The present work highlights the divergences between uncoupled, semi-coupled and coupled...
Tipo: Text
Palavras-chave: Couplage; Diffusion d’eau; Contrainte mécanique; Vieillissement; Polymères; Cordages synthétiques; Composites; Coupling; Water diffusion; Mechanical stress; Ageing; Polymers; Synthetic ropes; Composites.
Ano: 2017
URL: https://archimer.ifremer.fr/doc/00499/61023/64424.pdf

On the developments of spectral wave models: numerics and parameterizations for the coastal ocean
Provedor de dados: 5
Autores: Roland, Aron; Ardhuin, Fabrice.
The development of numerical wave models for coastal applications, including coupling with ocean circulation models, has spurred an ongoing effort on theoretical foundations, numerical techniques, and physical parameterizations. Some important aspects of this effort are reviewed here, and results are shown in the case of the French Atlantic and Channel coast using version 4.18 of the WAVEWATCH III R model. Compared to previous results, the model errors have been strongly reduced thanks to, among other things, the introduction of currents, coastal reflection, and bottom sediment types. This last item is described here for the first time, allowing unprecedented accuracy at some sites along the French Atlantic Coast. The adequate resolution, necessary to...
Tipo: Text
Palavras-chave: Wave modeling; Bottom friction; Coupling; Wave-current interaction.
Ano: 2014
URL: http://archimer.ifremer.fr/doc/00192/30288/29918.pdf

Environmental degradation of composites for marine structures: new materials and new applications
Provedor de dados: 5
Autores: Davies, Peter.
This paper describes the influence of seawater ageing on composites used in a range of marine structures, from boats to tidal turbines. Accounting for environmental degradation is an essential element in the multi-scale modelling of composite materials but it requires reliable test data input. The traditional approach to account for ageing effects, based on testing samples after immersion for different periods, is evolving towards coupled studies involving strong interactions between water diffusion and mechanical loading. These can provide a more realistic estimation of long-term behaviour but still require some form of acceleration if useful data, for 20 year lifetimes or more, are to be obtained in a reasonable time. In order to validate extrapolations...
Tipo: Text
Palavras-chave: Seawater; Immersion; Durability; Damage; Coupling.
Ano: 2016
URL: http://archimer.ifremer.fr/doc/00340/45167/44603.pdf

Prediction of long term strength of adhesively bonded steel/epoxy joints in sea water
Provedor de dados: 5
Autores: Bordes, Melanie; Davies, Peter; Cognard, J. -y.; Sohier, L.; Sauvant-moynot, V.; Galy, J.
This study is concerned with the development of a tool to predict the long term behaviour of adhesively bonded steel joints aged in sea water. First, diffusion kinetics and the mechanisms governing the degradation of mechanical properties of an epoxy adhesive are described. These two sets of data were used in a Coupled finite element (FE) analysis to determine the stress state in double lap shear (DLS) specimens before and after aging. However, subsequent tests on DLS specimens indicated an adhesive and not cohesive failure mode, so this approach could not be used to predict failure in the present case without introducing an interfacial damage parameter. A second approach was therefore employed, in which modified Arcan samples were designed in order to...
Tipo: Text
Palavras-chave: Coupling; Finite element stress analysis; Aging; Durability.
Ano: 2009
URL: http://archimer.ifremer.fr/doc/2009/publication-6968.pdf

How Coupled are Decoupled Farm Payments? A Review of Coupling Mechanisms and the Evidence
Provedor de dados: 31
Autores: Bhaskar,   Arathi; Beghin,   John C.
This survey paper explores the literature on decoupling of farm programs that has emerged in the last 10 years. The paper identifies and assesses the various channels of potential coupling of decoupled farm payments and provides taxonomy of coupling mechanisms found in theoretical and empirical papers. Coupling of decoupled payments is pervasive but effects when measurable are small, with the exception of the impact on land values. The paper points to unresolved issues on potential coupling mechanisms for further research.
Tipo: Working or Discussion Paper
Palavras-chave: Decoupling; Decoupled payments; Farm policy; Agricultural trade policy; Coupling; Direct payments; CCP; PFC; SFP; Agricultural and Food Policy; Agricultural Finance; Q17; Q18.
Ano: 2007
URL: http://purl.umn.edu/7347

Decoupled Direct Payments Under Base Acreage and Yield Updating Uncertainty: An Investigation of Agricultural Chemical Use
Provedor de dados: 31
Autores: Peckham,   Janet G.; Kropp,   Jaclyn D.
Decoupled payments were thought to have minimal impacts on current production decisions and input use. However, the literature has identified several mechanisms through which decoupled payments become coupled. We analyze the effects of uncertainty regarding future policy changes on farm-level production decisions and input use, focusing on farmers’ expectations of base acreage and yield updating. Using farm-level data, we find positive relationships between both decoupled and other government payments and real per acre expenditures on agricultural chemicals. Furthermore, there is evidence that decoupled payments may affect the intensive margin more than other government payments.
Tipo: Conference Paper or Presentation
Palavras-chave: Coupling; Decoupled payments; Input use; Intensive margin; Updating; Agricultural and Food Policy; Risk and Uncertainty; Q12; Q18.
Ano: 2010
URL: http://purl.umn.edu/61214

Improvement of the AROPAj model covering a large range of agricultural activities at wide (UE) and high resolution (mapping of farm types) scales
Provedor de dados: 31
Autores: Baranger,   Edouard; Clodic,   Melissa; Galko,   Elodie; Jayet,   Pierre-Alain; Zakharov,   Paul.
Mathematical programming models suit policy makers' needs for assessing impacts of new policies and modellers' needs for new parameters, constraints and activities to represent the phenomenon under study. The AROPAj model aims at taking into account any geographical extension of the European Union as well as the continuously changing Common Agricultural Policy. As well as the European policies will include more and more environmental problems, AROPAj will be more and more designed toward environmental assessments. Two improvement axes are set up. Biophysical models are used to refine the design of farming systems represented in the economic model and to estimate nitrogen pollutant emissions. Down-scaling methods are coupled with the regional farm group...
Tipo: Conference Paper or Presentation
Palavras-chave: Supply model; EU; Linear programming; Agriculture; Environment; Coupling; Down-scaling; Environmental Economics and Policy; Farm Management; Research Methods/ Statistical Methods; Resource /Energy Economics and Policy.
Ano: 2008
URL: http://purl.umn.edu/6664

Coupling Research on the Process of Transfer of Surplus Labor Forces and Scaling-up of Farmland
Provedor de dados: 31
Autores: Hu,   Ji-kui; Jiao,   Jian-jun.
On the basis of giving an overview of efficiency research on transformation of land from fragmentation to scale economy, by using the concept of coupling in physics, this paper expounds the behavior basis of transfer of surplus rural labor forces in China and transformation of land from fragmentation to scaling up, and analyzes behaviors of all parties and equilibrium outcomes in the three stages concerning the transformation of agricultural land from fragmentation to scaling up as follows. At the first stage of coupling after multitudinous rural surplus labor forces emerge. The farmers begin to go to city seeking jobs. In this period, the amalgamation of land management has not occurred and the single farmer's land has not yet concentrated. The total land...
Tipo: Article
Palavras-chave: Surplus labor forces; Fragmentation of farmland; Scaling up of farmland; Coupling; China; Agribusiness.
Ano: 2011
URL: http://purl.umn.edu/119702