Long term seismic response monitoring and finite element modeling of a concrete building considering soil flexibility and non-structural components

Peer reviewedPostprin

Finite element model updating of a RC building considering seismic response trends

ACKNOWLEDGEMENTS The authors would like to thank their supporters. GeoNet staff, particularly Dr Jim Cousins, Dr S.R. Uma and Dr Ken Gledhill, helped with access to seismic data and building information. Faheem Butt’s PhD study was funded by Higher Education Commission (HEC) Pakistan. Piotr Omenzetter’s work within The LRF Centre for Safety and Reliability Engineering at the University of Aberdeen is supported by The Lloyd's Register Foundation (The LRF). The LRF supports the advancement of engineering-related education, and funds research and development that enhances safety of life at sea, on land and in the air.Peer reviewedPostprin

Evaluation of seismic response trends from long-term monitoring of two instrumented RC buildings including soil-structure interaction

Peer reviewedPublisher PD

Laser diagnostics for NTP fuel corrosion studies

Viewgraphs and explanations on laser diagnostics for nuclear thermal propulsion (NTP) fuel corrosion studies are presented. Topics covered include: NTP fuels; U-Zr-C system corrosion products; planar laser-induced fluorescence (PLIF); utilization of PLIF for corrosion product characterization of nuclear thermal rocket fuel elements under test; ZrC emission spectrum; and PLIF imaging of ZrC plume

The Chandra X-Ray Observatory's Radiation Environment and the AP-8/AE-8 Model

The Chandra X-ray Observatory (CXO) was launched on July 23, 1999 and reached its final orbit on August 7, 1999. The CXO is in a highly elliptical orbit, approximately 140,000 km x 10,000 km, and has a period of approximately 63.5 hours (~ 2.65 days). It transits the Earth's Van Allen belts once per orbit during which no science observations can be performed due to the high radiation environment. The Chandra X-ray Observatory Center (CXC) currently uses the National Space Science Data Center's ``near Earth'' AP-8/AE-8 radiation belt model to predict the start and end times of passage through the radiation belts. However, our scheduling software uses only a simple dipole model of the Earth's magnetic field. The resulting B, L magnetic coordinates, do not always give sufficiently accurate predictions of the start and end times of transit of the Van Allen belts. We show this by comparing to the data from Chandra's on-board radiation monitor, the EPHIN (Electron, Proton, Helium Instrument particle detector) instrument. We present evidence that demonstrates this mis-timing of the outer electron radiation belt as well as data that also demonstrate the significant variablity of one radiation belt transit to the next as experienced by the CXO. We also present an explanation for why the dipole implementation of the AP-8/AE-8 model is not ideally suited for the CXO. Lastly, we provide a brief discussion of our on-going efforts to identify a model that accounts for radiation belt variability, geometry, and one that can be used for observation scheduling purposes.Comment: 12 pgs, 6 figs, for SPIE 4012 (Paper 76

Helping out: a national survey of volunteering and charitable giving

This report details the main findings of a national survey of volunteering and charitable giving – termed Helping Out – carried out by the National Centre for Social Research (NatCen) in partnership with the Institute for Volunteering Research (IVR) in 2006/07. The study was carried out for the Office of the Third Sector in the Cabinet Office. The main aims of the study were to examine: - how and why people give unpaid help to organisations, and what they think of their experiences; - what stops people from giving help; - the links between giving time and giving money; - how, why and how much people give money to charity; - what stops people from giving money to charity. There was also interest in estimates of the prevalence of volunteering and charitable giving. However, for a number of reasons (detailed in Chapters 2 and 10), prevalence estimates derived from this study should not be used to look at changes in these measures over time. Other study series are better suited to this purpose. In terms of volunteering, the study focused on formal help given through groups and organisations rather than informal help (given as an individual, e.g. to family and friends)

High Temperature Oxidation Kinetics of Dysprosium Particles

Rare earth elements have been recognized as critical materials for the advancement of many strategic and green technologies. Recently, the United States Department of Energy has invested many millions of dollars to enhance, protect, and forecast their production and management. The work presented here attempts to clarify the limited and contradictory literature on the oxidation behavior of the rare earth metal, dysprosium. Dysprosium particles were isothermally oxidized from 500 to 1000 °C in N2–(2%, 20%, and 50%) O2 and Ar–20% O2 using simultaneous thermal analysis techniques. Two distinct oxidation regions were identified at each isothermal temperature in each oxidizing atmosphere. Initially, the oxidation kinetics are very fast until the reaction enters a slower, intermediate region of oxidation. The two regions are defined and the kinetics of each are assessed to show an apparent activation energy of 8–25 kJ/mol in the initial region and 80–95 kJ/mol in the intermediate oxidation reaction region. The effects of varying the oxygen partial pressure on the reaction rate constant are used to show that dysprosium oxide (Dy2O3) generally acts as a p-type semiconductor in both regions of oxidation (with an exception above 750 °C in the intermediate region)

Stability and Decomposition of Ca-Substituted Lanthanum Ferrite in Reducing Atmospheres

Calcium-substituted lanthanum ferrites (La1–xCaxFeO3–δ x = 0, 0.1, 0.2, 0.3, 0.4) were synthesized in air and subsequently decomposed in reducing atmospheres. The partial pressure of oxygen (PO2) was controlled by varying the H2/H2O ratio by bubbling hydrogen/argon mixtures through water baths at controlled temperatures. Three regions of mass loss were identified as the PO2 was reduced, two of which were determined to be associated with decomposition reactions. Calcium was shown to decrease the thermal stability of the perovskite compound, but rather than incrementally increasing the required PO2 for decomposition proportional to calcium concentration, all samples partially decomposed at a single PO2. The extent of the partial decomposition was dependent on the amount of calcium substitution and temperature. The perovskite phase remaining after the partial decomposition was found to fully decompose at the same oxygen partial pressure as pure lanthanum ferrite

Supernova-Remnant Origin of Cosmic Rays?

It is thought that Galactic cosmic ray (CR) nuclei are gradually accelerated to high energies (up to ~300 TeV/nucleon, where 1TeV=10^12eV) in the expanding shock-waves connected with the remnants of powerful supernova explosions. However, this conjecture has eluded direct observational confirmation^1,2 since it was first proposed in 1953 (ref. 3). Enomoto et al.^4 claim to have finally found definitive evidence that corroborates this model, proposing that the very-high-energy, TeV-range, gamma-rays from the supernova remnant (SNR) RX J1713.7-3946 are due to the interactions of energetic nuclei in this region. Here we argue that their claim is not supported by the existing multiwavelength spectrum of this source. The search for the origin(s) of Galactic cosmic ray nuclei may be closing in on the long-suspected supernova-remnant sources, but it is not yet over.Comment: 4 pages, 1 Figur