2,051 research outputs found
Everlasting Shelters: life cycle energy assessment for heritage buildings
A total of twelve existing residential buildings (ten with heritage significance) were surveyed and modelled for their operational and embodied energy performance and their associated CO2 emissions in Australia and New Zealand. This paper presents an integrated life cycle framework, including energy flows associated with embodied energy, replacement of materials, construction processes and heating and cooling loads by combining life cycle modelling with esidential building energy rating software. The research found that overall, lower heating and cooling energy consumption does not necessarily lead to lower carbon emissions as carbon reduction depends on a number of factors including fuel mix profile and efficiency of the conventional grid. Buildings with ceiling insulation generally perform better in terms of energy usage especially in a colder climate and buildings made with heavy construction materials and with high thermal mass might work against the expected building fabric performance in a cold climatic condition with minimum solar gain. While the common perception is that old buildings often perform badly in terms of energy conservation, the higher rating for some of the buildings studied in this research shows that this is not always the case. The implications of this research apply not just to heritage buildings, but also to other existing buildings
Curriculum innovation in transnational teaching: A pilot study
Students are increasingly operating in a globalised world. Off shore education is challenging for students and teachers, as both need to make connections between local and culturally located knowledge and discipline. The relevant literature indicates that the transnational classroom has a number of challenges. Skills and knowledge of off shore and on shore teachers to enhance the quality of off shore learning and teaching are limited and unrealised. Off shore students experience culturally dislocated and disconnected pedagogies which impede student learning, engagement, program cohesion, and graduate outcomes. Yet, the transnational classroom also offers opportunities
A greenhouse gas assessment of a stadium in Australia
A greenhouse gas (GHG) life cycle assessment (LCA) was performed on a stadium used for sporting events in a subtropical region in Australia. Inventories for the construction and operation of a stadium are presented and the GHG emissions from construction, operations and end-of-life waste management are assessed against the attendance of one person at one event. The inclusion of additional economic activities, patron travel, LCA methodology, attendance and stadium life-time assumptions are likely to affect the overall magnitude of the GHG emissions of one person's attendance. The assessment shows that the stadium operation accounted for 72.5% of GHG emissions, with the operation of baseload heating, ventilation and cooling, lighting and refrigeration systems dominating. The best opportunity to reduce GHG emissions is to reduce the need for the continual operation of these systems. Construction impacts account for 24.7% of impacts, while replacement materials, end-of-life management of materials are relatively insignificant, contributing to less than 3% of life cycle GHG emissions
Management of late presentation congenital heart disease
In many parts of the world, mostly low- and middle-income countries, timely diagnosis and repair of congenital heart diseases (CHDs) is not feasible for a variety of reasons. In these regions, economic growth has enabled the development of cardiac units that manage patients with CHD presenting later than would be ideal, often after the window for early stabilisation - transposition of the great arteries, coarctation of the aorta - or for lower-risk surgery in infancy - left-to-right shunts or cyanotic conditions. As a result, patients may have suffered organ dysfunction, manifest signs of pulmonary vascular disease, or the sequelae of profound cyanosis and polycythaemia. Late presentation poses unique clinical and ethical challenges in decision making regarding operability or surgical candidacy, surgical strategy, and perioperative intensive care management
Quasi-normal modes of Schwarzschild-de Sitter black holes
The low-laying frequencies of characteristic quasi-normal modes (QNM) of
Schwarzschild-de Sitter (SdS) black holes have been calculated for fields of
different spin using the 6th-order WKB approximation and the approximation by
the P\"{o}shl-Teller potential. The well-known asymptotic formula for large
is generalized here on a case of the Schwarzchild-de Sitter black hole. In the
limit of the near extreme term the results given by both methods are
in a very good agreement, and in this limit fields of different spin decay with
the same rate.Comment: 9 pages, 1 ancillary Mathematica(R) noteboo
Progress in development of tapes and magnets made from Bi-2223 superconductors
Long lengths of (Bi,Pb)2Sr2Ca2Cu3O(x) tapes made by powder-in-tube processing have been wound into coils. Performance of the coils has been measured at temperatures of 4.2 to 77 K, and microstructures have been examined by x-ray diffraction and electron microscopy and then related to superconducting properties. A summary of recent results and an overview of future goals are presented
Enhanced electrical resistivity before N\'eel order in the metals, RCuAs (R= Sm, Gd, Tb and Dy
We report an unusual temperature (T) dependent electrical resistivity()
behavior in a class of ternary intermetallic compounds of the type RCuAs
(R= Rare-earths). For some rare-earths (Sm, Gd, Tb and Dy) with negligible
4f-hybridization, there is a pronounced minimum in (T) far above
respective N\'eel temperatures (T). However, for the rare-earths which are
more prone to exhibit such a (T) minimum due to 4f-covalent mixing and
the Kondo effect, this minimum is depressed. These findings, difficult to
explain within the hither-to-known concepts, present an interesting scenario in
magnetism.Comment: Physical Review Letters (accepted for publication
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Processing and properties of Ag-clad BSCCO superconductors
Long lengths of mono- and multifilament Ag-clad BSCCO (Bi-Sr-Ca-Cu-O) conductors with critical current densities of >10{sup 4} A/cm{sup 2} at 77 K were fabricated by the powder-in-tube method. {Tc} magnets were assembled by stacking pancake coils fabricated from long tapes and then tested vs applied magnetic field at various temperatures. A magnet that contained {approx}2400 m of {Tc} conductor generated a field of 3.2 T at 4.2 K. In-situ tensile and bending properties of the Ag-clad conductors were studied. Multilayer Ag/superconductor composites were fabricated by chemical etching. Preliminary results with multilayer tapes show that continuous Ag reinforcement of the BSCCO core improves strain tolerance of the tapes so they can carry 90% of their initial I{sub c} at 1% bend strain desite a higher superconductor/Ag ratio than that of unreinforced tapes
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Processing and fabrication of high-{Tc} superconductors for electric power applications
Recent developments in the powder-in-tube fabrication of (Bi,Pb){sub 2}Sr{sub 2}Ca{sub 2}Cu{sub 3}O{sub x} tapes include identification of high current transport regions of the superconductor core, optimization of conductor design and processing to take advantage of these high current regions, optimization of superconductor powders and heat treatments, and incorporation of flux pinning defects into the superconductor grains. These developments are briefly discussed and their implications are assessed
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