The Ethanol Trap: Why Policies to Promote Ethanol as Fuel Need Rethinking

Government support for ethanol production is expensive for governments and costly for consumers.economic growth and innovation, ethanol fuel

An examination of automatic video retrieval technology on access to the contents of an historical video archive

Purpose – This paper aims to provide an initial understanding of the constraints that historical video collections pose to video retrieval technology and the potential that online access offers to both archive and users. Design/methodology/approach – A small and unique collection of videos on customs and folklore was used as a case study. Multiple methods were employed to investigate the effectiveness of technology and the modality of user access. Automatic keyframe extraction was tested on the visual content while the audio stream was used for automatic classification of speech and music clips. The user access (search vs browse) was assessed in a controlled user evaluation. A focus group and a survey provided insight on the actual use of the analogue archive. The results of these multiple studies were then compared and integrated (triangulation). Findings – The amateur material challenged automatic techniques for video and audio indexing, thus suggesting that the technology must be tested against the material before deciding on a digitisation strategy. Two user interaction modalities, browsing vs searching, were tested in a user evaluation. Results show users preferred searching, but browsing becomes essential when the search engine fails in matching query and indexed words. Browsing was also valued for serendipitous discovery; however the organisation of the archive was judged cryptic and therefore of limited use. This indicates that the categorisation of an online archive should be thought of in terms of users who might not understand the current classification. The focus group and the survey showed clearly the advantage of online access even when the quality of the video surrogate is poor. The evidence gathered suggests that the creation of a digital version of a video archive requires a rethinking of the collection in terms of the new medium: a new archive should be specially designed to exploit the potential that the digital medium offers. Similarly, users' needs have to be considered before designing the digital library interface, as needs are likely to be different from those imagined. Originality/value – This paper is the first attempt to understand the advantages offered and limitations held by video retrieval technology for small video archives like those often found in special collections

Anisotropic interaction of two-level systems with acoustic waves in disordered crystals

We apply the model introduced in Phys. Rev. B 75, 064202 (2007), cond-mat/0610469, to calculate the anisotropy effect in the interaction of two level systems with phonons in disordered crystals. We particularize our calculations to cubic crystals and compare them with the available experimental data to extract the parameters of the model. With these parameters we calculate the interaction of the dynamical defects in the disordered crystal with phonons (or sound waves) propagating along other crystalographic directions, providing in this way a method to investigate if the anisotropy comes from the two-level systems being preferably oriented in a certain direction or solely from the lattice anisotropy with the two-level systems being isotropically oriented.Comment: 10 page

The role of the computer in learning ndjébbana

While Computer Assisted Language Learning (CALL) is being superseded by an integrated approach to language learning and technology, it still has great potential to assist indigenous peoples in becoming print-literate in their own languages. This can also help to combat the disempowerment experienced by indigenous people as their world is penetrated by others with radically different backgrounds. This paper reports on research on an application of CALL implemented among the Kunibídji, a remote, indigenous Australian community. It focuses on the use of talking books in Ndjébbana, a language with only 200 speakers; the books were displayed on touch-screens at various locations in the community. Investigations into the roles of the computer to support language learning and cultural understanding are also reported. The computer was found to be a useful tool in promoting Kunibídji collaboration and cultural transformation

Schooling, cognitive ability, and health

A large literature documents a strong correlation between health and educational outcomes. In this paper we investigate the role of cognitive ability in the health–education nexus. Using NLSY data, we show that cognitive ability accounts for roughly one quarter of the association between schooling and health. Both schooling and ability are strongly associated with health at low levels but less related or unrelated at high levels. Estimates treating schooling as endogenous to health suggest that most of the correlation between schooling and health is attributable to unobserved heterogeneity, except possibly at low levels of schooling for individuals with low cognitive ability. An implication is that policies which increase schooling will only increase health to the extent that they increase the education of poorly-educated individuals; subsidies to college education, for example, are unlikely to increase population health.education, health, intelligence, correlated random coefficient models