Cuba | EPFL Graph Search

Cuba (ˈkjuːbə , ˈkuβa; Erekusú), officially the Republic of Cuba (República de Cuba reˈpuβlika ðe ˈkuβa), is an island country comprising the island of Cuba, as well as Isla de la Juventud and several minor archipelagos. Cuba is located where the northern Caribbean Sea, Gulf of Mexico, and Atlantic Ocean meet. Cuba is located east of the Yucatán Peninsula (Mexico), south of both the American state of Florida and the Bahamas, west of Hispaniola (Haiti/Dominican Republic), and north of both Jamaica and the Cayman Islands. Havana is the largest city and capital; other major cities include Santiago de Cuba and Camagüey. The official area of the Republic of Cuba is (without the territorial waters) but a total of including the exclusive economic zone. Cuba is the second-most populous country in the Caribbean after Haiti, with over 11 million inhabitants. The territory that is now Cuba was inhabited as early as the 4th millennium BCE, with the Guanahatabey and Taíno peoples inhabiting the

Alternatives pour la réalisation de logements par auto-construction. Le quartier du Vaquerito (Santa-Clara, Cuba)

Guillaume Roux-Fouillet

En 2004, à Cuba, le logement se trouve dans une situation problématique : c'est un bien social qui revient de droit à chaque cubain, mais que l'Etat ne parvient plus à fournir à la population. Les interventions urbanistiques et architecturales prévues par l'Etat sont actuellement paralysées. L'auto-construction se présente alors comme la seule méthode de production de logements encore efficace. Cependant celle-ci se réalise inévitablement de manière anarchique en raison de l'accumulation des différents problèmes propres à Cuba (approvisionnement en matériaux, qualité constructive, absence de planification à terme, etc.) et surtout en raison de la non-urbanisation par l'Etat des zones prévues pour ce mode de construction. Ainsi le développement actuel est incompatible avec une future urbanisation satisfaisante. Cependant, si les actions constructives concrètes de l'Etat sont difficiles à imaginer dans l'immédiat, il reste un grand potentiel d'action au niveau de la gestion du processus de construction et de l'organisation sociale du quartier. Pour avoir une chance de voir le jour dans cette situation, un projet architectural réaliste doit proposer une stratégie progressive et durable pour sa réalisation. Ce projet s'organise sur la base des infrastructures institutionnelles existantes et emploie, au niveau local, une démarche participative pour conduire les travaux selon un enchaînement d'étapes, depuis la fabrication des matériaux de construction jusqu'à la construction des logements.

2004

Cuba, Best Practices: quel potentiel d'élargissement

The present article evaluates the knowledge that can be attributed to the application of « Best Practices » in the field of urban habitat. It especially aims at identifying the conditions of innovation in such a setting, as well as defining the necessary circumstances for an enlargement – or even the replication - of « Best Practices ». The analysis is based on the study of programs and projects carried out by the NGO “Habitat-Cuba” between 1994 and 2001. Two key aspects of the question will be highlighted: the “powers’ peripheral character of this type of programs and the “suspension” of a certain number of standards as a condition for success. The article thus underlines the fragility of these experiences in the longer term.

2007

Distribution of platinum-group elements and Os isotopes in chromite ores from Mayari-Baracoa Ophiolitic Belt (eastern Cuba)

Reto Frei, Anders Meibom

The Mayari-Baracoa ophiolitic belt in eastern Cuba hosts abundant chromite deposits of historical economic importance. Among these deposits, the chemistry of chromite ore is very variable, ranging from high Al (Cr#=0.43-0.55) to high Cr (Cr#=0.60-0.83) compositions. Platinum-group element (PGE) contents are also variable (from 33 ppb to 1.88 ppm) and correlate positively with the Cr# of the ore. Bulk PGE abundances correlate negatively with the Pd/Ir ratio showing that chromite concentrates mainly Os, Ir and Ru which gives rise to the characteristic negatively sloped, chrondrite-normalized PGE patterns in many chromitites. This is consistent with the mineralogy of PGEs, which is dominated by members of the laurite-erlichmanite solid solution series (RuS2-OsS2), with minor amounts of irarsite (IrAsS), Os-Ir alloys, Ru-Os-Ir-Fe-Ni alloys, Ni-Rh-As, and sulfides of Ir, Os, Rh, Cu, Ni, and/or Pd. Measured Os-187/Os-188 ratios (from 0.1304 to 0.1230) are among the lower values reported for podiform chromitites. The Os-187/Os-188 ratios decrease with increasing whole-rock PGE contents and Cr# of chromite. Furthermore, gamma Os values of all but one of the chromitite samples are negative indicating a subchondiritc mantle source. gamma Os decrease with increasing bulk Os content and decreasing Re-187/Os-188 ratios. These mineralogical and geochemical features are interpreted in terms of chromite crystallization from melts varying in composition from back-arc basalts (Al-rich chromite) to boninites (Cr-rich chromite) in a suprasubduction zone setting. Chromite crystallization occurs as a consequence of magma mixing and assimilation of preexisting gabbro sills at the mantle-crust transition zone. Cr#, PGE abundances, and bulk Os isotopic composition of chromitites are determined by the combined effects of mantle source heterogeneity, the degree of partial melting, the extent of melt-rock interactions, and the local sulfur fugacity. Small-scale (mu m to cm) chemical and isotopic heterogeneities in the platinum-group minerals are controlled by the mechanism(s) of chromite crystallization in a heterogeneous environment created by the turbulent regime generated by successive inputs of different batches of melt.

2005

Distribution of platinum-group elements and Os isotopes in chromite ores from Mayari-Baracoa Ophiolitic Belt (eastern Cuba)

Reto Frei, Anders Meibom

2005