Search results for " bagging"
showing 5 items of 5 documents
Mechanical behavior of carbon/flax hybrid composites for structural applications
2012
In this work, the influence of an unidirectional carbon fabric layer on the mechanical performances of bidirectional flax fabric/epoxy composites used for structural applications was studied. Two different bidirectional flax fabrics were used to produce flax fabric reinforced plastic (FFRP) laminates by a vacuum bagging process: one is normally used to make curtains; the other, heavier and more expensive than the previous one, is usually used as reinforcement in composite structures. In order to realize hybrid structures starting from FFRP, an unidirectional UHM carbon fabric was used to replace a bidirectional flax fabric. Tensile and three-point bending tests were performed to evaluate t…
Influence of resin viscosity and vacuum level on mechanical performance of sandwich structures manufactured by vacuum bagging
2010
The choice of process parameters is critical in optimizing the mechanical properties of sandwich structures produced using the vacuum bagging technique. The aim of this paper is to analyze how the viscosity of the resin/curing agent system and the vacuum level influence the morphology and the mechanical behavior of sandwich beams with composite faces (epoxy resin and glass fiber fabric named COMBI 900) and a PVC foam core. Four different sandwich structures were produced by varying the viscosity of the epoxy resin/curing agent at constant maximum vacuum pressure. Three further structures were manufactured by varying the strength of the vacuum with the resin viscosity maintained constant at …
Ottimizzazione di strutture sandwich per applicazioni nautiche
2008
Effect of UD carbon on the specific mechanical properties of glass mat composites for marine applications
2009
In this work the influence of a uniaxial carbon fabric layer on the mechanical performances of a glass mat/epoxy composite used for marine applications has been studied. All the structures have been made, at room temperature, by vacuum bagging technique. Tension and flexural tests have been carried out in order to evaluate the specific mechanical properties of the composite and to compare these with those of the marine aluminium alloy 6016-T4. The glass composites have higher specific strength but lower specific modulus than aluminium alloy. To increase the specific modulus of the composites, each layer of glass mat has been replaced with a layer of uniaxial carbon fabric. In addition, a s…
ENSEMBLE METHODS FOR RANKING DATA
2017
The last years have seen a remarkable flowering of works about the use of decision trees for ranking data. As a matter of fact, decision trees are useful and intuitive, but they are very unstable: small perturbations bring big changes. This is the reason why it could be necessary to use more stable procedures, as ensemble methods, in order to find which predictors are able to explain the preference structure. In this work ensemble methods as BAGGING and Random Forest are proposed, from both a theoretical and computational point of view, for deriving classification trees when ranking data are observed. The advantages of these procedures are shown through an example on the SUSHI data set.