5,351 research outputs found
Internal friction investigation of phase transformation in nearly stoichiometric LaMnO3+ÎŽ
Rhombohedral LaMnO3+ÎŽ powders, prepared by two different soft chemistry routes (co-precipitation and hydrothermal synthesis), are sintered at 1400 °C for 2 h in air. Measurements of internal friction Qâ1(T) and shear modulus G(T), at low frequencies from â180 to 700 °C under vacuum, evidence three structural transitions of nearly stoichiometric orthorhombic LaMnO3+ÎŽ. The first one, at 250 or 290 °C, depending on the processing followed, is associated to either a JahnâTeller structural transition or a phase transformation from orthorhombic to pseudo-cubic. The second one at 610 or 630 °C is related to a phase transformation from pseudo-cubic or orthorhombic to rhombohedral. Below the Neel temperature, around â170 °C, a relaxation peak could be associated, for samples prepared according to both processing routes, to the motion of Weiss domains
Evaluation of a programme of transferable skills development within the PhD: views of late stage students
Recent years have seen an increasing emphasis placed upon the development of transferable skills within PhD degree programmes. This paper reports on steps taken to evaluate a programme of transferable skills development at a research intensive university in the UK, focussing on the views of late stage PhD students in the science, engineering and medical disciplines. It shows that most students report a positive impact from having taken part in transferable skills initiatives and that they have a positive attitude towards them. Participants report an enduring positive impact on their behaviour and consider that the training meets their perceived needs as they progress as researchers. However, amongst the population as a whole, there were differences in views. For example, it was found that females, overseas students and those mainly motivated to do the PhD by career-related reasons attach the greatest importance to such opportunities to develop transferable skills
Studies on European beech (Fagus sylvatica L.). Part 1: Variations of wood colour parameters
Colour parameters of European beech were measured using CIELab system. 103
logs from 87 trees in 9 sites were cut into boards to study the variations of
wood colour parameters. Both site and tree effect on colour were observed.
Patterns of red heartwood occurrence were defined. When excepting red heartwood
there was still a highly significant effect of site and tree; differences
remained after veneer processing. Axial variations were small, except very near
the pith or in red heartwood, suggesting possible early selection at periphery
under colour criteria. Red heartwood is darker, redder and more yellow than
normal peripheral wood.Comment: to be published in Annals of Forest Science reception 12.8.04;
acceptation 15.2.0
Modelling of ill-known requirements and integration in production planning
Making decisions on the base of uncertain forecasts is one of the key challenges for efficient Supply Chain Management. This article suggests the use of the theory of possibility for building a procurement plan on the base of ill-known requirements. These requirements, expressed in quantities by date, may come from various sources: forecasts or orders for instance. The possible types of imperfection pervading requirement are analysed and a unified representation model is suggested. A method is then described for calculating a plausible demand by period without loss of information; it is illustrated on an example in the last section
Integration of the supplier capacity for choosing the less risked schedule within an uncertain environment
This communication addresses the integration of the supplier capacity in the procurement planning process of a customer within a supply chain. Since this supply chain evolves within an uncertain environment, uncertainties may be due to an ill-known demand (prevision) and to the customer production system (scraps, imprecise processing time...). Thus, we propose a collaborative process where the customer aims at taking the less risked decision. The integration of the supplier capacity in the gross requirement enables to assess the risk of back order so that the feasibility of the requirement plan. It then enables the customer to make the decisions which limit this risk
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