The onset and association of CMEs with sigmoidal active regions

Previous studies of active regions characterised by Soft X-ray S or inverse-S morphology [Canfield et al., 1999], have found these regions to possess a higher probability of eruption. In such cases, CME launch has been inferred using X-ray proxies to indicate eruption. Active regions observed during 1997, previously categorised as both sigmoidal and eruptive [Canfield, 1999], have been selected for further study, incorporating SoHO-LASCO, SoHO-EIT and ground based H-alpha data. Our results allow re-classification into three main categories; sigmoidal, non-sigmoidal and active regions appearing sigmoidal due to the projection of many loops. Although the reduced dataset size prevents a statistical measure of significance, we note that regions comprising a single S (or inverse-S) shaped structure are more frequently associated with a CME than those classed as non-sigmoidal. This motivates the study of a larger dataset and highlights the need for a quantitative observational definition of the term "sigmoid"

Heat transfer in a compact tubular heat exchanger with helium gas at 3.5 MPa

A compact heat exchanger was constructed consisting of circular tubes in parallel brazed to a grooved base plate. This tube specimen heat exchanger was tested in an apparatus which radiatively heated the specimen on one side at a heat flux of up to 54 W/sq cm, and cooled the specimen with helium gas at 3.5 MPa and Reynolds numbers of 3000 to 35,000. The measured friction factor of the tube specimen was lower than that of a circular tube with fully developed turbulent flow, although the uncertainty was high due to entrance and exit losses. The measured Nusselt number, when modified to account for differences in fluid properties between the wall and the cooling fluid, agreed with past correlations for fully developed turbulent flow in circular tubes

Population health profile of the NSW Outback Division of General Practice: supplement

© Commonwealth of Australia To view the data presented in the profiles in Excel spreadsheets or via Interactive Mapping, please see the PHIDU website at: www.publichealth.gov.au

Population health profile of the Northern Melbourne Division of General Practice

© Commonwealth of Australia To view the data presented in the profiles in Excel spreadsheets or via Interactive Mapping, please see the PHIDU website at: www.publichealth.gov.au