Environmental Management for Agriculture (EMA) and Sustainable Agriculture

John Tzilivakis and Kathleen Lewis, ‘Environmental Management for Agriculture (EMA) and Sustainable Agriculture’, paper presented at the 2nd European Conference of the European Federation for Information Technology in Agriculture, Food and the Environment, 27 – 30 September 1999, Bonn, Germany.Submitted Versio

Numerical modelling of hailstone impact on the leading edge of a wind turbine blade

The scale of modern blades means that tip speeds in excess of 100ms-1 are now common in utility scale turbines. Coupling this with a hailstone terminal velocity ranging from 9ms-1 to 40ms-1, the relative impact velocity becomes highly significant. There is little published data on the performance of blade materials under these impact conditions and as such this work aims to understand the impact phenomena more clearly and consequently characterize the impact performance of the constitutive blade materials. To better understand hailstone impact, the LS-DYNA explicit dynamics code was employed to simulate hailstone impact on the blade leading edge. A Smooth Particle Hydrodynamics approach (SPH) was chosen to represent the hailstone geometry. It was found that the forces and stresses created during hail impact are significant and in some cases damaging, therefore posing both short and long term risks to the material integrity. It was also found that coating systems such as the gel coat provide essential – and in extreme conditions, sacrificial – protection to the composite substrate

CHORUS Deliverable 2.1: State of the Art on Multimedia Search Engines

Based on the information provided by European projects and national initiatives related to multimedia search as well as domains experts that participated in the CHORUS Think-thanks and workshops, this document reports on the state of the art related to multimedia content search from, a technical, and socio-economic perspective. The technical perspective includes an up to date view on content based indexing and retrieval technologies, multimedia search in the context of mobile devices and peer-to-peer networks, and an overview of current evaluation and benchmark inititiatives to measure the performance of multimedia search engines. From a socio-economic perspective we inventorize the impact and legal consequences of these technical advances and point out future directions of research

The Management and Use of Social Network Sites in a Government Department

In this paper we report findings from a study of social network site use in a UK Government department. We have investigated this from a managerial, organisational perspective. We found at the study site that there are already several social network technologies in use, and that these: misalign with and problematize organisational boundaries; blur boundaries between working and social lives; present differing opportunities for control; have different visibilities; have overlapping functionality with each other and with other information technologies; that they evolve and change over time; and that their uptake is conditioned by existing infrastructure and availability. We find the organisational complexity that social technologies are often hoped to cut across is, in reality, something that shapes their uptake and use. We argue the idea of a single, central social network site for supporting cooperative work within an organisation will hit the same problems as any effort of centralisation in organisations. We argue that while there is still plenty of scope for design and innovation in this area, an important challenge now is in supporting organisations in managing what can best be referred to as a social network site 'ecosystem'.Comment: Accepted for publication in JCSCW (The Journal of Computer Supported Cooperative Work

Tracking Bacterial Pollution Sources in Hampton Harbor

Fecal-borne microorganisms impact many shellfish-growing waters in coastal New Hampshire. Watersheds are often subject to fecal contamination by a variety of sources and efforts to improve water quality are often limited because of lack of information on which contaminant sources are most significant. Ribotyping and other microbial source tracking methods are useful new tools for providing information on the sources of fecal-borne bacterial contaminants in surface waters. New Hampshire has areas of abundant oyster (Crassostrea virginica) and clam (Mya arenaria) resources, the latter being most important in Hampton Harbor. In this study, Escherichia coli isolates (bacteria colonies) were obtained from water samples collected from ten sites in Hampton Harbor year-round during both dry and wet conditions. A library of known E. coli isolates was created from twenty different potential source species in the New Hampshire coastal watershed, including humans, livestock, pets, wildlife and avian species. The ribosomal RNA DNA of E. coli isolates was analyzed using ribotyping in which the patterns of ribosomal DNA were detected using chemiluminescence, then optimized and analyzed using GelCompar II software. A total of 249 isolates from the twenty known source species were used as a reference to identify sources for 390 unknown isolates from water samples taken from August 2000 through October 2001. Banding patterns for water samples and source species isolates were considered to be the same if there was 80% or greater similarity between patterns. Overall, sources for 62% of the isolates were identified