On triangular lattice Boltzmann schemes for scalar problems

We propose to extend the d'Humi\'eres version of the lattice Boltzmann scheme to triangular meshes. We use Bravais lattices or more general lattices with the property that the degree of each internal vertex is supposed to be constant. On such meshes, it is possible to define the lattice Boltzmann scheme as a discrete particle method, without need of finite volume formulation or Delaunay-Voronoi hypothesis for the lattice. We test this idea for the heat equation and perform an asymptotic analysis with the Taylor expansion method for two schemes named D2T4 and D2T7. The results show a convergence up to second order accuracy and set new questions concerning a possible super-convergence.Comment: 23 page

Are Young and Old Workers Harmful for Firm Productivity?

This paper investigates the effects of the workforce age structure on the productivity of large Belgian firms. More precisely, it examines different scenarios of changes in the proportion of young (16-29 years), middle-aged (30-49 years) and old (more than 49 years) workers and their expected effects on firm productivity. Using detailed matched employer-employee data, we find that a higher share of young (old) workers within firms is favourable (harmful) for firm value added per capita. Results also show that age structure effects on productivity are stronger in ICT than in non-ICT firms.workforce age structure, demographic changes, firm performance

While we were away…

The most distressing news from China over the holidays was the severe sentence (11 years in prison) handed to dissident Liu Xiaobo for his involvement in the writing and organization of Charter ’08 in December 2008. For those who are catching up on this story, a brief set of readings to bring you up to speed on the situation

Lattice Boltzmann model approximated with finite difference expressions

We show that the asymptotic properties of the link-wise artificial compressibility method are not compatible with a correct approximation of fluid properties. We propose to adapt the previous method through a framework suggested by the Taylor expansion method and to replace first order terms in the expansion by appropriate three or five points finite differences and to add non linear terms. The "FD-LBM" scheme obtained by this method is tested in two dimensions for shear wave, Stokes modes and Poiseuille flow. The results are compared with the usual lattice Boltzmann method in the framework of multiple relaxation times

Adoption, fosterage et alliance

Adoption, fosterage et allianceMoyennant certaines précautions, il est possible de considérer la captation momentanée ou définitive d'enfants comme un processus de circulation articulé à celui du mariage. Les relations entre ces deux institutions peuvent être envisagées comme des rapports d'implication, médiatisés ou directs, comme des rapports de substitution ou comme des rapports d'inclusion. Les circuits d'adoption-fosterage, lorsqu'ils se répètent à travers le temps, peuvent soit emprunter des trajets spécifiques, soit se modeler sur des circuits matrimoniaux connus.Adoption, Fosterage and MarriageSubject to certain precautions, the temporary or permanent placing of children in a family can be considered to be like a process of circulation interlinked with that of marriage. The relationships between these two institutions can be envisaged as: 1. Relationships of involvement, either mediated or direct. 2. Relationships of substitution. 3. Relationships of inclusion. Networks of adoption-fosterage, when repeated over time, can either present their own specific pattern or follow well-known matrimonial networks

La question du secret de la naissance dans les sociétés « traditionnelles »

La question du secret de la naissance dans les sociétés « traditionnelles » (note de recherche)Cette note de recherche fait l’inventaire des attitudes et raisons alléguées contre le secret de la naissance lors de l’adoption chez les populations de droit plutôt oral et traditionnel, d’une part, et des attitudes et argumentaires de leurs opposants dans le même type de société, d’autre part. On postule une analogie de situation entre le face-à-face des partisans du rejet des parents biologiques et ceux qui prônent une coopération entre parents initiaux et d’adoption avec, en société de droit écrit à évolution rapide, les cas de procréation médicalement assistée : certains renvoient à l’anonymat des donneurs de gamètes et des mères porteuses ; d’autres estiment qu’un pacte de transparence entre intervenants et vis-à-vis de l’enfant serait mieux adapté socialement à ces nouvelles pratiques, suivant en cela le modèle majoritaire des sociétés traditionnelles.The Question of Secrecy Pertaining to Origins in “Traditional” Societies (Research Note)This research note is an analysis of attitudes and reasons given against, or for, secrecy surrounding birth, among societies that are regulated mostly by oral and traditional laws. The author postulates an analogy of situations between these societies, rejecting biological parents, or, to the contrary, practising an adoptive circulation of children, and fast changing industrialised societies with written laws, searching to provide families with descendants through medically assisted procreation. Some recommend that gamete donors or surrogate mothers be anonymous. Others, following the model most often used in “traditional” societies, suggest that transparency between the various actors and toward the child may be socially better suited to these new practices.La cuestión del secreto del nacimiento en las sociedades « tradicionales » (nota de investigación)Inventario de actitudes y de razones avanzadas contra el secreto del nacimiento durante la adopción entre las poblaciones regidas por el derecho oral y tradicional ; en seguida actitudes y argumentos de sus opuestos en el mismo tipo de sociedad. Se postula una analogía de situación entre el confrontamiento entre los partidarios del rechazo de los padres biológicos y quienes preconizan la cooperación entre los padres iniciales y la adopción, en sociedad de derecho escrito en rápida evolución, con el caso de la procreación médica asistida : algunos remiten al anonimato a los donantes de gametos y a las madres que llevan en su útero el ovulo fecundado In Vitro, otros estiman que un pacto transparente entre las partes interesadas con respecto al niño, sería, según el modelo mayoritario de las sociedades tradicionales, socialmente bien adaptada a las nuevas practicas

Alien Registration- Lallemand, Raoul (Sanford, York County)

https://digitalmaine.com/alien_docs/3185/thumbnail.jp