Perpendicular Weak Permanent Magnetic Field Effect on the Electrodeposited Nanostructured ZnO Film and its Kinetic Corrosion Behavior

Protection of Metals and Physical Chemistry of Surfaces - In this work the effect of the permanent weak magnetic field on the electrodeposited ZnO nanostructured film on the ITO substrate...     

Tracing the evolution of HCI patterns as an interaction design tool

Design patterns have been introduced as a medium to capture and disseminate the best design knowledge and practices. In the field of human–computer interaction, practitioners and researchers have explored different avenues to use patterns and pattern languages as design tools. This paper surveys these avenues—from individual pattern use for solving a specific design problem, to pattern-oriented design, which guides designers in building a conceptual design by leveraging relationships between patterns. One of our underlying goals is to investigate how patterns can be used, not only to foster the reuse of proven and valid design solutions, but also as a central artefact in the process of deriving a design from user experiences and requirements. We will present our investigations on pattern-based design, and discuss how user experiences can be incorporated in the pattern selection process through the use of user variables, pattern attributes and associated relationships.     

About the influence of temperature and matrix ductility on the behavior of carbon woven-ply PPS or epoxy laminates: Notched and unnotched laminates

Could thermoplastic-based composites be used to replace thermosetting-based composites in high-temperature secondary aircraft structures? The purpose of this work is to establish the ability of a material system to be used in aircraft engine nacelles when subjected to static loadings, with a key upper temperature of 120 °C. In order to provide answers to this question, the thermo-mechanical behaviors of carbon fiber fabric reinforced PPS or epoxy laminates have been compared specifically within the temperature change with 120 °C at the upper bound. The temperature-dependent ductile behavior of laminates is more or less exacerbated, depending on polymers glass transition temperature, and laminates stacking sequence. For both materials, the degree of retention of tensile mechanical properties is quite high in notched and unnotched quasi-isotropic laminates. A Digital Image Correlation technique has been used in order to understand the influence of temperature and matrix ductility on the mechanisms of overstresses accommodation near the hole. In fabric reinforced laminates, the high-temperature results suggest a competition between the mechanisms of damage, and the mechanism of plasticization, enhanced in angle-ply lay-ups. Thus, the highly ductile behavior of TP-based laminates, at temperatures higher than their T_g, is very effective to accommodate the overstresses near the hole.     

Numerical simulation of the effect of grain size on corrosion processes: Surface roughness oscillation and cluster detachment

This work reports on the numerical simulation results of the grain size effect on the corrosion processes using a cellular automata model. The material considered consists of domains and their edges. The domains represent the monocrystalline cores while their edges represent the intergranular defects. Either a periodic pattern or randomly generated domains of Voronoï tessellation are used. The model parameters, taking into account the polycrystalline aspect of corrosion, are the domain density and the corrosion probabilities of metal grain core and grain boundary sites. The corrosion probability for grain edge is taken as higher than for the grain core. A complicated surface structure appears with a high geometrical roughness if the density of defects is not too high. A strong correlation between the roughness evolution, the metal crystalline properties and the corrosion mechanism of the metal dissolution was established.     

The Inhibition Performance of trans-Cinnamaldehyde as a Green Compound for Mild Steel in Acidic 1 M HCl Medium: Correlation between Experimental and Theoretical Studies

Protection of Metals and Physical Chemistry of Surfaces - Corrosion inhibition propriety of (2E)-3-phenylprop-2-enal, known as trans-cinnamaldehyde (TCA) for mild steel in 1 M HCl medium was...     

The role of the experimental data base used to identify material parameters in predicting the cyclic plastic response of an austenitic steel

The first objective of this paper investigates the influence of the previous strain history on ratcheting. New tests were performed where different strain-controlled histories have been applied prior to ratcheting tests. It is demonstrated that under the same conditions, one can observe ratcheting, plastic shakedown or elasticity according to the prior strain-controlled history. The second objective points out the correlation between the experimental data base devoted to the identification of the material parameters and the quality of the predictions in cyclic plasticity. The results suggest that the choice of the tests should be closely linked to the capabilities of the model. In particular, the presence of non proportional strain-controlled tests in the data base may be not a good choice if the model itself is not able to represent explicitly such a character. All tests considered here were performed on 304L SS at room temperature.     

Retrofitting of reinforced concrete beams using composite laminates

This paper presents the results of an experimental study to investigate the behaviour of structurally damaged full-scale reinforced concrete beams retrofitted with CFRP laminates in shear or in flexure. The main variables considered were the internal reinforcement ratio, position of retrofitting and the length of CFRP. The experimental results, generally, indicate that beams retrofitted in shear and flexure by using CFRP laminates are structurally efficient and are restored to stiffness and strength values nearly equal to or greater than those of the control beams. It was found that the efficiency of the strengthening technique by CFRP in flexure varied depending on the length. The main failure mode in the experimental work was plate debonding in retrofitted beams.     

Recent trends in IP/NGEO satellite communication systems: transport, routing, and mobility management concerns

Non-geostationary (NGEO) satellite communication systems are seen as an attractive solution to realize the vision of anywhere, anytime pervasive access to the Internet. Their design and development have thus gained tremendous interest in the last few years. Commencing with a brief overview of general NGEO satellite configurations, this article next addresses the key technical difficulties in the development of NGEO IP-based satellite communications systems. The article discusses routing concerns, mobility management, and transport protocols with an emphasis on TCP performance in NGEO satellite networks. Some key innovations are presented. The recursive, explicit, and fair window adjustment (REFWA) scheme is presented as a solution to improve the efficiency and fairness of TCP in NGEO systems. An improvement to the REFWA scheme, REFWA plus, is also described to combat link errors in satellite environments.