Start where you are: Graphic ordering influences improvisational dance

This article is an analysis and reflection on the role of lists and diagrams in Start where you are, a multimedia improvisational piece performed as part of square zero independent dance festival: the second edition/la deuxième édition. This interdisciplinary festival was organised by collective (gulp) dance projects and took place in Ottawa, Canada, in August 2005. Start where you are was the result of a collaboration between the authors: two dance artists (Andrew and MacKinnon, the principals of (gulp)) and a visual communication designer (Gillieson). A sound artist and a lighting technician also participated in the work. This is a post-performance retrospective meant to analyze more closely the experience that meshed the evidentiary weight of words and graphics with the ephemerality and subjectivity of movement-based live performance. It contextualizes some of the work of collective (gulp) within a larger tradition of improvisation in modern dance. It also looks at how choice-making processes are central to improvisation, how they relate to Start, and how linguistic material can intersect with and support improvisational performance. Lastly, it examines some characteristics of lists and diagrams, unique forms of visual language that are potentially rich sources of material for improvisation.

Mass and size distribution measurement of particulates from a gas turbine combustor using modern mobility analyzer and particle sizer

SMPS and DMS500 analysers were used to measure particulate size distributions in the exhaust of a fully annular aero gas turbine engine at two operating conditions to compare and analyse sources of discrepancy. A number of different dilution ratio values were utilised for the comparative analysis, and a Dekati hot diluter operating at a temperature of 623°K was also utilised to remove volatile PM prior to measurements being made. Additional work focused on observing the effect of varying the sample line temperatures to ascertain the impact. Explanations are offered for most of the trends observed, although a new, repeatable event identified in the range from 417°K to 423°K – where there was a three order of magnitude increase in the nucleation mode of the sample – requires further study.

Seasonality of modern pollen and sediment deposition in an estuarine context: the Severn Estuary Levels, southwest England

Recent sedimentological and palynological research on subfossil Holocene banded sediments from the Severn Estuary Levels suggested seasonality of deposition, registered by variations in mineral grain-size and pollen assemblages between different parts of the bands. Here we provide data that strengthen this interpretation from sampling of modern sediments and pollen deposition on an active mudflat and saltmarsh on the margin of the Severn Estuary, and comparison with a vegetation survey and contemporary records of climate, river and tidal regimes. The results of grain-size analysis indicate deposition of comparatively coarse-grained silts during the relatively cool and windy conditions of winter and comparatively fine-grained sediments during relatively warm and calm summer months. Pollen analysis demonstrates the significance of long-term storage of pollen grains and fern spores in the estuarine waterbody, superimposed on which seasonal variations in pollen inputs from local and regional vegetation remain detectable. Copyright (C) 2007 John Wiley & Sons, Ltd.

Seasonality of delta C-13 and C/N ratios in modern and mid-holocene sediments in the Severn Estuary levels, SW Britain

Bulk organic VC and C/N ratios from mid-Holocene salt-marsh deposits with sedimentary banding reveal subtle but significant differences between coarse- and fine-grained deposits. These are consistent with findings from seasonally sampled modern silts, and with the interpretation, on physical and palynological grounds, of the fine-grained and coarse-grained components as warm-season and cold-season deposits, respectively. The control is considered to be seasonal variations in the character of the organic matter supplied.

Evolution of the modern Nile delta promontories: development of accretional features during shoreline retreat

The active accretional features that have developed along the modern Nile Delta promontories during shoreline retreat are analysed using topographic maps, remote imagery, ground and hydrographic surveys, together providing 15 time-slice maps (1922-2000) at Rosetta and 14 time-slice maps (1909-2000) at Damietta. Small double sandy spits developed and persisted at Rosetta between 1986 and 1991. At Damietta, a much larger single spit, 9 km long, formed approximately east of the mouth of the Damietta Nile branch between 1955 and 1972, although its source has now been depleted. Both the Rosetta and Damietta inlets are associated with submerged mouth bars that accumulated prior to the damming of the Nile, but that continue to contribute to local sedimentation problems, particularly at Rosetta. The development of the active accretional features along the Nile promontories reflects a combination of factors including sediment availability, transport pathways from source areas, a decrease in the magnitude of Nile flood discharges, as well as the impact of protective structures at the river mouths.

Ensemble-based data assimilation and the localisation problem

The “butterfly effect” is a popularly known paradigm; commonly it is said that when a butterfly flaps its wings in Brazil, it may cause a tornado in Texas. This essentially describes how weather forecasts can be extremely senstive to small changes in the given atmospheric data, or initial conditions, used in computer model simulations. In 1961 Edward Lorenz found, when running a weather model, that small changes in the initial conditions given to the model can, over time, lead to entriely different forecasts (Lorenz, 1963). This discovery highlights one of the major challenges in modern weather forecasting; that is to provide the computer model with the most accurately specified initial conditions possible. A process known as data assimilation seeks to minimize the errors in the given initial conditions and was, in 1911, described by Bjerkness as “the ultimate problem in meteorology” (Bjerkness, 1911).