An overview of the Lejeuneaceae in Australia

As currently understood, the Lejeuneaceae flora of Australia consists of 122 species in 27 genera. The family occurs almost exclusively in rainforested areas along the eastern coast of the continent. Based on species composition, three floristic regions are recognized: tropical, subtropical and temperate. The tropical region contains 80 percent of the total number of Lejeuneaceae found in Australia, the subtropical region contains 45 percent, and the temperate region only 15 percent of the total flora. The affinities of the Lejeuneaceae in the tropical and subtropical regions are strongest with the Asian flora, and those of the temperate region are strongest with the New Zealand flora. The diversity of the Lejeuneaceae flora in Australia is higher than might be expected for a non-equatorial region. This diversity may result from the wide variety of rainforest habitats that are available along both latitudinal and altitudinal gradients. The temperate flora is probably derived from that which existed in Australia, New Zealand, Antarctica and probably southern South America prior to the breakup of Gondwanaland. The modern tropical flora is probably a mixture of species that were part of the original northern Gondwanan flora and those that have invaded more recently

A re-evaluation of Cheilolejeunea subgenus Xenolejeunea

Cheilolejeunea subgenus Xenolejeunea Kachroo & Schust. is emended to account for variability observed in stem anatomy and lobule structure. Cheilolejeunea subgenus Tegulilejeunea Schust. is reduced to synonymy with subgenus Xenolejeunea. A new sectional classification of subgenus Xenolejeunea is proposed (sections Gigantae, Meyenianae, and Xenolejeunea). A key distinguishes among the sections and the 10 species accepted in the subgenus, which is known from Australasia, Oceania and tropical Asia. A nomenclator and discussion is provided for each species. Comments on excluded species conclude the treatment

Hymne à la déesse Tanent et présence latopolite sur quelques blocs d’Ermant

International audiencePublication of a set of loose blocks coming from the area of Bab el-Maganin at Armant. On the upper register, a priestess presents sistra to Tanent followed by four other deities. The lower register bears the representation of two goddesses, one with a crocodile head, the other with a vulture head. Each goddess protects with her arms different kind of objects or child. The hieroglyphic text is a hymn to Tanent, in which she is linked with other goddesses.Publication d'un ensemble lapidaire provenant du secteur de Bab el-Maganin à Ermant. Sur le registre supérieur, une prêtresse présente les sistres à la déesse Tanent suivie par quatre autres déesses. Le registre inférieur livre la représentation de deux déesses, l'une à tête de crocodile, l'autre à tête de vautour. Chaque déesse protège des ses mains différents objets ou jeunes enfants. Le texte hiéroglyphique qui accompagne ces représentations est un hymne à la déesse Tanent

Armant: recent discoveries at the temple of Montu-Re

International audienceResults of the 2013 season of the French-Egyptian Archaeological Mission at Arman

Seismic control of rocking structures using inerters

When subjected to lateral excitations, a variety of structures, such as museum artefacts, historical buildings, bridge piers and post-tensioned walled buildings, might uplift and set into rocking motion. Although this mechanism can efficiently limit the internal forces at their base, the possibility of overturning or experiencing increased lateral deformations and accelerations may severely affect the functionality of rocking structures. Nevertheless, suitable seismic control strategies are presently limited and consist mostly in preventing rocking motion altogether, which may induce undesirable stress concentrations and lead to impractical interventions. This thesis examines the alternative of using supplemental rotational inertia devices to control the seismic response of rocking structures. The newly proposed strategy employs inerters, which are mechanical devices that develop resisting forces proportional to the relative acceleration between their terminals and can be combined with a clutch to ensure they act only in opposition to the motion. The fundamental dynamic behaviour of the system is firstly examined considering a free-standing rigid block model. By deriving the corresponding equations of motion, it is demonstrated that the inclusion of the inerter effectively reduces the frequency parameter of the block, resulting in lower seismic demands and enhanced stability due to the well‐known size effects of the rocking behaviour. In subsequent chapters, this simplified single-degree-of-freedom model is gradually extended in order to incorporate the effects of post-tensioned tendons, structural flexibility and higher modes on the response. Overall, the analyses conducted under coherent pulses and real ground motion records show that inerter-equipped structures experience reduced seismic demands and lower probabilities of exceeding limit states usually associated with structural and non-structural damage. The fundamental knowledge acquired in the first part of this thesis is finally applied to control the seismic response of rocking timber buildings. To this end, a set of three post-tensioned rocking walled buildings, comprising 3, 6 and 9 storeys, is designed following direct-displacement-based design guidelines. Additionally, a set of clutched and non-clutched ball-screw and gear inerters is designed using a newly proposed pre-dimensioning procedure. The performance of bare and protected structures with different levels of apparent mass ratios is then compared in terms of peak inter-storey drifts and floor accelerations. Special attention is paid to the resisting forces developed in the inerters and the mechanism to transfer them to the structural diaphragm. Likewise, the ability of the inerters to control higher-mode effects is closely examined. Finally, a performance-based assessment with particular emphasis on non-structural and contents damage is conducted considering a database of 202 pulse-like ground motion records. Overall, the results of this assessments confirm the trends observed in the analytical examinations of the earlier chapters.Open Acces

Life cycle assessment of a positive energy house in France

Disponible à l'adresse : http://leso.epfl.ch/files/content/sites/leso/files/download/publications/cisbat_proceedings_final_download.pdfInternational audienceThe « positive energy house » concept combines energy saving, e.g. applying the passive house approach, and electricity production using a renewable resource, leading to a positive primary energy balance on a yearly basis. Compared to a standard house, more materials and components are used (thicker insulation, triple glazing windows, renewable energy systems...), this is why the environmental relevance of this concept is often questioned. In order to contribute to answer this question, a life cycle assessment (LCA) has been used to evaluate the environmental impacts of such buildings, including the fabrication of components, construction, operation, maintenance, dismantling and waste treatment. This paper presents results in the case of a positive energy building, showing also the influence of the choice of the heating system on various environmental impacts considered in this assessment (e.g. global warming potential, radioactive waste production, photochemical oxidant formation potential, cumulative energy demand, abiotic depletion potential). The case study concerns two attached passive houses built in Picardy, France, in which renewable energy systems are studied theoretically: the real houses include solar water heating but no renewable electricity production. The envelope has a high insulation, high airtightness and very low thermal bridges. The technical equipment includes a heat recovery ventilation and an earth-to-air heat exchanger. In this study, PV solar panels mounted on the roof have been added so as to obtain a positive primary energy assessment. For these houses, three different heating solutions have been studied: an electric heat-pump, a wood pellet condensing boiler and a wood pellet micro-cogeneration unit. The three alternatives have been modeled using the building thermal simulation tool COMFIE, in order to evaluate their heating load, possibly cooling load and thermal comfort level. Environmental impact indicators have been evaluated for these alternatives applying the LCA tool EQUER, linked to the building simulation tool COMFIE and using life cycle inventories from the Swiss Ecoinvent data base

Des éco-techniques à l'éco-conception des bâtiments

Disponible sur internet : http://perso.univ-lr.fr/fcherqui/IBPSAmars2006/02_BPeuportier.pdfNational audienceLes recherches menées à l'École des Mines de Paris depuis la fin des années 70 ont porté sur diverses techniques d'économie d'énergie et d'intégration des énergies renouvelables dans les bâtiments (solaire passif, solaire actif, solaire photovoltaïque). Plus récemment, des travaux ont été initiés sur les échangeurs air/sol (appelés parfois " puits canadiens "). Des modèles de bâtiments ont été développés pour évaluer les besoins de chauffage, de climatisation et d'éclairage, puis ils ont été étendus à l'évaluation des impacts environnementaux par l'analyse de cycle de vie. La programmation orientée objets a permis de capitaliser les connaissances, en facilitant le chaînage de ces différents modèles. Cet ensemble logiciel comporte un certain nombre de limites, en particulier sur la prise en compte des mouvements d'air, de l'humidité et de certains équipements. Des activités complémentaires de validation seraient utiles, en particulier dans le cas de bâtiments à très faibles besoins. L'utilisation de ces outils comme aide à la conception est facilitée par une interface conviviale, qui pourrait encore être améliorée de manière à progresser vers l'écoconception des bâtiments. Enfin, une extension à l'échelle d'un quartier est en cours de développement. Research activities have been performed at Ecole des Mines de Paris since the seventies, regarding energy efficient techniques and the integration of renewable energy systems in buildings (passive and active solar, photovoltaic systems). More recently, earth/air heat exchangers have been studied. Building models have been developed to evaluate heating, cooling and lighting loads. Thesenmodels have been complemented with life cycle assessment in order to estimate environmental impacts. Object oriented programming allowed the modelling contributions on each technique to be integrated in a whole software package. The limits of this model concern air movements, humidity transfer, and some types of equipment. Complementary validation work would be useful, particularly for low energy buildings. The use of these tools as design aid benefits from a user friendly interface, but further improvement would still be useful in order to progress towards eco-design. Finally, an extension of the models at a settlement level is in progress