Micro-simulating child poverty in 2010 and 2020

The 2008 Pre-Budget Report (PBR) said that 'the Government will take stock of progress towards its 2010 and 2020 child poverty target in the [2009] Budget'. As background to that exercise, this paper updates our previous analysis of the prospects for child poverty in the UK in 2010-11 and 2020-21

A computer simulation of Skylab dynamics and attitude control for performance verification and operational support

A simulation of the Skylab attitude and pointing control system (APCS) is outlined and discussed. Implementation is via a large hybrid computer and includes those factors affecting system momentum management, propellant consumption, and overall vehicle performance. The important features of the flight system are discussed; the mathematical models necessary for this treatment are outlined; and the decisions involved in implementation are discussed. A brief summary of the goals and capabilities of this tool is also included

Hydrogen environment embrittlement of astroloy and Udimet 700 (nickel-base) and V-57 (iron-base) superalloys

The sensitivity to hydrogen environment embrittlement of three superalloys was determined. Astroloy forgings were resistant to embrittlement during smooth tensile, notched tensile, and creep testing in 3.5-MN/sq m hydrogen over the range 23 to 760 C. The notched tensile strength of Udimet 700 bar stock in hydrogen at 23 C was only 50 percent of the baseline value in helium. Forgings of V-57 were not significantly embrittled by hydrogen during smooth tensile testing over the range 23 to 675 C; creep and rupture lives of V-57 were degraded by hydrogen. Postcreep tensile ductility of V-57 was reduced by 40 percent after creep exposure in hydrogen

Does text structure/summarization instruction facilitate learning from expository text?

The work upon which this publication is based was performed pursuant to Contract no. NIE-400-81-0030 of the National Institute of Educatio

The influence of atmosphere on the performance of pure-phase WZ and ZB InAs nanowire transistors

We compare the characteristics of phase-pure MOCVD grown ZB and WZ InAs nanowire transistors in several atmospheres: air, dry pure N$_2$ and O$_2$, and N$_2$ bubbled through liquid H$_2$O and alcohols to identify whether phase-related structural/surface differences affect their response. Both WZ and ZB give poor gate characteristics in dry state. Adsorption of polar species reduces off-current by 2-3 orders of magnitude, increases on-off ratio and significantly reduces sub-threshold slope. The key difference is the greater sensitivity of WZ to low adsorbate level. We attribute this to facet structure and its influence on the separation between conduction electrons and surface adsorption sites. We highlight the important role adsorbed species play in nanowire device characterisation. WZ is commonly thought superior to ZB in InAs nanowire transistors. We show this is an artefact of the moderate humidity found in ambient laboratory conditions: WZ and ZB perform equally poorly in the dry gas limit yet equally well in the wet gas limit. We also highlight the vital role density-lowering disorder has in improving gate characteristics, be it stacking faults in mixed-phase WZ or surface adsorbates in pure-phase nanowires.Comment: Accepted for publication in Nanotechnolog

The use of LANDSAT digital data and computer-implemented techniques for an agricultural application

Agricultural applications procedures are described for use of LANDSAT digital data and other digitalized data (e.g., soils). The results of having followed these procedures are shown in production estimates for cotton and soybeans in Washington County, Mississippi. Examples of output products in both line printer and map formats are included, and a product adequacy assessment is made

Decoherence of spin echoes

We define a quantity, the so-called purity fidelity, which measures the rate of dynamical irreversibility due to decoherence, observed e.g in echo experiments, in the presence of an arbitrary small perturbation of the total (system + environment) Hamiltonian. We derive a linear response formula for the purity fidelity in terms of integrated time correlation functions of the perturbation. Our relation predicts, similarly to the case of fidelity decay, faster decay of purity fidelity the slower decay of time correlations is. In particular, we find exponential decay in quantum mixing regime and faster, initially quadratic and later typically gaussian decay in the regime of non-ergodic, e.g. integrable quantum dynamics. We illustrate our approach by an analytical calculation and numerical experiments in the Ising spin 1/2 chain kicked with tilted homogeneous magnetic field where part of the chain is interpreted as a system under observation and part as an environment.Comment: 22 pages, 10 figure