Taking context into account in conceptual models using a Model Driven Engineering approach

Context

In public transport, travelers (considered as information systems users) do not have the same objectives and/or concerns at the same time. For this reason it is not always easy to provide them with the right information at the right time. If personalizing the information to the user allows to do this to some extend it is not enough since the information could also depend on the use of the context and the environment (e.g., place, time, etc.).

Objective

This paper proposes a solution allowing the context to be managed inside an application’s conceptual models in order to provide more flexible web applications from the user’s point of view.

Method

Our work is based on a modeling method using the Model Driven Engineering (MDE) approach and on practical field experiences permitting us to validate our solution. Our domain of application is personalized transport information.

Results

Introducing the notion of context into rules and decision trees that are used inside conceptual models allowed us to incorporate context as important information for personalizing web applications.

Conclusion

The context should be integrated into an application during the modeling phase to allow a smooth integration inside the application and to facilitate the evolution over time. Our solution offers a better user’s experience through an extended personalization of web applications.     

Performance analysis of four-pad hydrostatic squeeze film dampers loaded between pads under laminar and turbulent flow conditions

This paper presents a theoretical study of the effects of Poiseuille Reynolds number and eccentricity ratio on the performance of four-pad hydrostatic squeeze film dampers. The finite difference method has been used to solve Reynolds equation based on Constantinescu’s turbulent lubrication theory. The numerical results obtained are analysed and compared between three and four-lobe hybrid journal bearings. The computed results indicate that the performance of a hydrostatic squeeze film damper loaded between pads is significantly influenced by the flow regimes. The results presented in this work can be useful to the bearing designers.     

A geometrical proof of the persistence of normally hyperbolic submanifolds

We present a simple, computation-free and geometrical proof of the following classical result: for a diffeomorphism of a manifold, any compact submanifold that is invariant and normally hyperbolic persists under small perturbations of the diffeomorphism. The persistence of a Lipschitz invariant submanifold follows from an application of the Schauder fixed point theorem to a graph transform, while smoothness and uniqueness of the invariant submanifold are obtained through geometrical arguments. Moreover, we also prove a new result on the persistence and regularity of ‘topologically’ normally hyperbolic submanifolds, but without any uniqueness statement.     

Finite element comparison of single and bi-layered tube hydroforming processes

In this paper, single and bi-layered tube hydroforming processes were numerically simulated using the finite element method. It was found that the final bulges heights resulted from the models were in good agreement with the experimental results. Both types of modeling have been kept with the same geometry, tube material, and process parameters to compare between the obtained hydroformed products (branch height, thickness reduction, and wrinkling) using different loading path types. Results were discussed.     

Dendrosomes as novel gene porters‐III

BACKGROUND: It was previously reported that dendrosomes, i.e. neutral, biodegradable, covalent or self‐assembled, hyperbranched, spheroidal nano‐particles with a size ranging from 15 to 100 nm, provide a convenient and efficient means of gene delivery into various kinds of cells such as human hepatoma and kidney cells as well as animal models. RESULTS: New studies via circular dichroism show that hydrophilic and amphipathic dendrosomes either do not affect the DNA structure or moderately transform it from B‐ to A‐conformation. Gene delivery into human liver, kidney, and endothelial cells as well as other animal cells like Bowes, U‐937, Raw, CCRF‐CEM, MOLT‐4, K562, Huh‐7 and VERO reveal that the genes are efficiently expressed and in comparison with other gene porters like Lipofectin or bacterial ghosts, do quite well. It is also shown that dendrosomes are able to deliver genes into cells like endothelials that are usually hard to transfect. Cell culture experiments as well as intraperitoneal/intradermal injections of dendrosomes into mice establish their nontoxicity (up to 2.5 mg kg^?1 of animal weight in the latter case). Studies on immunization of BALB/c mice using conventional adjuvants such as aluminium phosphate, C_pG motif and one of the dendrosomes, indicate that the latter leads to the mildest initial response development while exceeding them afterwards. CONCLUSION: CD studies reveal that, owing to the neutrality of dendrosomes, formation of Den/DNA complexes is accompanied by slight structural modifications of DNA cell culture, and animal studies reveal that dendrosomes are inert, non‐toxic and highly efficient gene porters that perform at extremely low doses. In comparison with bacterial ghosts and some common porters, they are efficient in delivery of genes into animals and a variety of cells including those that are usually hard to transfect. Copyright © 2008 Society of Chemical Industry     

Securing physical layer using new chaotic parametric maps

Multimedia Tools and Applications - In this work, to overcome the flaws of standard chaotic maps we generated two new cascaded structures, 3D Cubic-Sine and 2D Cubic-Cat chaotic parametric maps,...     

Analysis of Side Information Impact on the Coverage Region of Wireless Wiretap Channel

Wireless Personal Communications - Analyzing wireless communication performances by using information-theoretic results is of practical importance. In this paper, first, an achievable secrecy rate...     

Numerical modeling of natural convection in an open cavity with two vertical thin heat sources subjected to a nanofluid

This paper presents a numerical study of natural convection cooling of two heat sources vertically attached to horizontal walls of a cavity. The right opening boundary is subjected to the copper–water nanofluid at constant low temperature and pressure, while the other boundaries are assumed to be adiabatic. The governing equations have been solved using the finite volume approach, using SIMPLE algorithm on the collocated arrangement. The study has been carried out for the Rayleigh number in the range 10⁴ ≤ Ra ≤ 10⁷, and for solid volume fraction 0 ≤ φ ≤ 0.05. In order to investigate the effect of heat source location, three different placement configurations of heat sources are considered. The effects of both Rayleigh numbers and heat source locations on the streamlines, isotherms, Nusselt number are investigated. The results indicate that the flow field and temperature distributions inside the cavity are strongly dependent on the Rayleigh numbers and the position of the heat sources. The results also indicate that the Nusselt number is an increasing function of the Rayleigh number, the distance between two heat sources, and distance from the wall. In addition it is observed that the average Nusselt number increases linearly with the increase in the solid volume fraction of nanoparticles.     

Transportation ontology definition and application for the content personalization of user interfaces

Ontologies have been largely exploited in many domains and studies. In this paper, we present a new application of a domain ontology for generating personalized user interfaces for transportation interactive systems. The concepts, relationships and axioms of transportation ontology are exploited during the semi-automatic generation of personalized user interfaces. Personalization deals with the capacity of adaptation of a user interface, reflecting what is known about the user and the domain application. It can be performed on the interface container presentation (e.g., layout, colors, sizes) and in the content provided in their input/output (e.g., data, information, document). In this paper, the transportation ontology is used to provide the content personalization. This paper presents the ontology and how it is used for the personalization of user interfaces for developing transportation interactive systems by model-driven engineering.     

Influence of ageing on the internal friction of magnesium

The internal friction of cp- (99.8 wt.%) and hp- (99.99 wt.%) magnesium was determined by measuring the logarithmic decrement of free vibrations of bending beams, which were clamped at one end. Independently of the purity and the thermomechanical pretreatment, for all samples the logarithmic decrement increases with increasing strain amplitude. The damping in hp-magnesium is generally higher than in cp-magnesium. This can be explained by the model of Granato and Lücke, assuming that the successive unpinning of dislocation segments between weak pinning points is the reason of the increment of damping with increasing strain amplitude. The weak pinning points are assumed to be solute atoms or vacancies. Based on this model, other effects, found also in time and stress dependent internal friction measurements, can be explained qualitatively. The damping decreases at room temperature with ageing time and annealing temperatures up to 150°C. For higher annealing temperatures the damping increases monotonously with the temperature of the heat treatment. The effect of ageing can also be reverted by dynamic strain in the range of about 10⁻⁴–10⁻³, which increases the internal friction of aged samples before they can age again.