Bayesian approach to sapwood estimates and felling dates in dendrochronology

An improved method of generating sapwood estimates for oak is developed. This suggests a revision of the 95% confidence range from 10–40 to 9–36 rings for trees from southern England. Current methods for estimating felling dates on timbers with incomplete sapwood do not generate true 95% confidence limits, and a Bayesian method for deriving such limits is presented. For timbers with no sapwood, the addition of 12 years to the date of the final ring is shown to give a 95% confidence limit on the terminus post quem for felling. The further application of these methods is illustrated by calculation of the common felling date for timbers from the Great Kitchen at Windsor Castle

Facebook and the People in the Iron House: 非死不可？

“Maybe we will block content in some countries, but not others,” Adam Conner, a Facebook lobbyist, told the [Wall Street] Journal. “We are occasionally held in uncomfortable positions because now we’re allowing too much, maybe, free speech in countries that haven’t experienced it before,” he said

Electronics implementation of the solar neutron experiment

The electronic equipment design and function are discussed for the solar neutron counter experiment. Circuit diagrams are included

Towards a semantic modeling of learners for social networks

The Friend of a Friend (FOAF) ontology is a vocabulary for mapping social networks. In this paper we propose an extension to FOAF in order to allow it to model learners and their social networks. We analyse FOAF alongside different learner modeling standards and specifications, and based on this analysis we introduce a taxonomy of the different features found in those models. We then compare the learner models and FOAF against the taxonomy to see how their characteristics have been shaped by their purpose. Based on this we propose extensions to FOAF in order to produce a learner model that is capable of forming the basis of a semantic social network.<br/

Space station thermal control surfaces

Mission planning documents were used to analyze the radiator design and thermal control surface requirements for both space station and 25-kW power module, to analyze the missions, and to determine the thermal control technology needed to satisfy both sets of requirements. Parameters such as thermal control coating degradation, vehicle attitude, self eclipsing, variation in solar constant, albedo, and Earth emission are considered. Four computer programs were developed which provide a preliminary design and evaluation tool for active radiator systems in LEO and GEO. Two programs were developed as general programs for space station analysis. Both types of programs find the radiator-flow solution and evaluate external heat loads in the same way. Fortran listings are included