A practical guide to the Freedom of Information Act 2000

The Constitution Unit has rewritten the Practical Guide to the Freedom of Information Act 2000. The revised edition differs considerably from the original in format and content. Foremest among the changes are the three case studies (with comments) at the end and the references to recently published, more detailed official advice. The guide is designed for practitioners who are responsible for or otherwise involved in their authority's plans to implement and operate the FoI Act. The guide serves as an introduction to implementation and operation of the FoI Act, focusing specifically on its core principles and features, how public authorities should prepare for implementation and what FoI practitioners should do when they receive requests for information

Coupled-channel calculation of bound and resonant spectra of Lambda-9Be and Lambda-13C hypernuclei

A Multi-Channel Algebraic Scattering (MCAS) approach has been used to analyze the spectra of two hyper-nuclear systems, Lambda-9Be and Lambda-13C. The splitting of the two odd-parity excited levels (1/2^- and 3/2^-) at 11 MeV excitation in Lambda-13C is driven mainly by the weak Lambda-nucleus spin-orbit force, but the splittings of the 3/2^+ and 5/2^+ levels in both Lambda-9Be and Lambda-13C have a different origin. These cases appear to be dominated by coupling to the collective 2+ states of the core nuclei. Using simple phenomenological potentials as input to the MCAS method, the observed splitting and level ordering in Lambda-9Be is reproduced with the addition of a weak spin-spin interaction acting between the hyperon and the spin of the excited target. With no such spin-spin interaction, the level ordering in Lambda-9Be is inverted with respect to that currently observed. In both hyper-nuclei, our calculations suggest that there are additional low-lying resonant states in the Lambda-nucleus continua.Comment: 15 pages, 3 figures, 6 tables. To be published in International Journal of Modern Physics

The supervised hierarchical Dirichlet process

We propose the supervised hierarchical Dirichlet process (sHDP), a nonparametric generative model for the joint distribution of a group of observations and a response variable directly associated with that whole group. We compare the sHDP with another leading method for regression on grouped data, the supervised latent Dirichlet allocation (sLDA) model. We evaluate our method on two real-world classification problems and two real-world regression problems. Bayesian nonparametric regression models based on the Dirichlet process, such as the Dirichlet process-generalised linear models (DP-GLM) have previously been explored; these models allow flexibility in modelling nonlinear relationships. However, until now, Hierarchical Dirichlet Process (HDP) mixtures have not seen significant use in supervised problems with grouped data since a straightforward application of the HDP on the grouped data results in learnt clusters that are not predictive of the responses. The sHDP solves this problem by allowing for clusters to be learnt jointly from the group structure and from the label assigned to each group.Comment: 14 page

Energy Conversion Alternatives Study (ECAS), Westinghouse phase 1. Volume 4: Open recuperated and bottomed gas turbine cycles

Open-cycle recuperated gas turbine plant with inlet temperatures of 1255 to 1644 K (1800 to 2500 F) and recuperators with effectiveness values of 0, 70, 80 and 90% are considered. A 1644 K (2500 F) gas turbine would have a 33.5% plant efficiency in a simple cycle, 37.6% in a recuperated cycle and 47.6% when combined with a sulfur dioxide bottomer. The distillate burning recuperated plant was calculated to produce electricity at a cost of 8.19 mills/MJ (29.5 mills/kWh). Due to their low capital cost $170 to 200$/kW, the open cycle gas turbine plant should see duty for peaking and intermediate load duty