Electric Shadows (Dianying) *

Catalogue Essay on Isaac Julien's installation "Ten Thousand Waves". Probably also included in catalogue for Isaac Julien exhibition Sao Paulo Autumn 201

Modelling rain drop impact on offshore wind turbine blades

The effects of rain and hail erosion and impact damage on the leading edge of offshore wind turbine blades have been investigated. A literature review was conducted to establish the effects of exposure to these conditions and also to investigate the liquid impact phenomena and their implications for leading edge materials. The role of Explicit Dynamics software modelling in simulating impact events was then also established. Initial rain impact modelling is then discussed with the results showing good agreement with theoretical predictions both numerically and with respect to the temporal and spatial development of the impact event. Future development of the rain model and a proposed hail model are then detailed. Planned rain impact and erosion testing work is addressed which will be used to validate, inform and compliment the ongoing modelling efforts

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

Gait Extraction and Description by Evidence-Gathering

Using gait as a biometric is of increasing interest, yet there are few model-based, parametric, approaches to extract and describe moving articulated objects. One new approach can detect moving parametric objects by evidence gathering, hence accruing known performance advantages in terms of performance and occlusion. Here we show how that the new technique can be extended not only to extract a moving person, but also to extract and concurrently provide a gait signature for use as a biometric. We show the natural relationship between the bases of these approaches, and the results they can provide. As such, these techniques allow for gait extraction and description for recognition purposes, and with known performance advantages of a well-established vision technique

Screen theory and film culture, 1977-1987

My work in the 1970s and 1980s was developed with the evolving body of work now loosely called 'c e theory'. It centred on notions of authorship, spectatorship and art cinema with specific reference to the films of Carl Dreyer. In my research and writing on Dreyer's film Vampyr I applied the literary concept of the fantastigue to cinema, one of the first substantial theoretical contributions to a now established area of publication and research. According to one writer' this work was "probably the most ambitious attempt to apply Todorov's approach to cinema", a "notable exception" in the theoretical writing of that time. This was part of the wider movement associated with SEFT and Screen to interrogate the uncritical realism which dominated 1970s film studies. In my subsequent writing on Dreyer I explored a structuralist but more psychoanalytically informed discussion of genre, developing the concept of the "Dreyer text" as a way of bringing psychoanalytic concepts to compliment and complicate structuralist notions of authorship and genre. I was part of a loose group at Screen which was passionate both about cinema and ideas. While polemically defending the new concepts we were bringing to bear on cinema, we were equally concerned with their institutional placing. Our work concentrated both on regimes of looking allowed to the spectator by texts and their institutional placing. We focussed on political and discursive structures of the cinematic institution and developed a concept of 'cinema as social practice'. In particular I pushed for a cultural critique of British Independent cinema and its institutions, which was continued in my work on screen acting. I was also instrumental in extending Screen theory to other visual arts. I felt that the sometime parochialism of film studies lay in part in its separation from analysis of other forms of visual culture. In my full context statement I wish to explore limitations in the political, semiotic and psychoanalytic models which I (as did many others) adopted at the time. What I now see as Screen theory's 'blind spots' in relation to issues of sexual orientation and race can be traced back to the problematic of this period. My own subsequent research on gay and lesbian cinema as well as film and television projects on screen acting (Acting Tapes) psychoanalysis (Between Two Worlds) and Frantz Fanon (Frantz Fanon: Black Skin White Mask) came out of dissatisfaction with that earlier project as it was then conceived. The form chosen - the essay and review - reflects the difficulty of thinking through these issues. [James Donald (ed), 'Fantasy and the Cinema', British Film Institute, London 1989] In essence my proposal involves looking back at my work around Dreyer and what one could broadly call my 'film culture' work, and arguing that what was sometimes felt and described as a theory: practice division between these two domains could be more usefully thought of in retrospect in terms of two overlapping modes of theoretical production involving different notions of institution, conjuncture, subject etc. In looking again at the strengths and weaknesses of the work I am submitting here, however, I still expect key terms of subject and history, discourse and institution, to remain in place, modified and nuanced by the substantial range of work in psychoanalysis, cultural studies and queer theory that Screen in part engendered and which my work participated in.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Shellfish Spotlight: 2008

Each year Granite State shellfishers search shallow briny waters in search of delicious mussels, clams, or oysters for the dinner table. Those who are skilled often are rewarded with full buckets, but few shellfishers realize that good harvests in New Hampshire’s Seacoast owe much to activities occurring far upstream. The quality of the water and amount of available nutrients that sustain a clam or oyster is directly related to the condition of the rivers and streams that drain the land. The Hampton-Seabrook Estuary is fed by approximately 46 square miles of surrounding land. An even larger system, the Piscataqua River Estuary that includes Great Bay, is supplied by a watershed that is 1,023 square miles. Development within the coastal watershed area has profound impacts on the amount of contaminants flowing to the sea. Sediment washed from roadways and bare soil flows downstream and collects in the estuary where it smothers shellfish beds in extreme cases. Nutrients, primarily nitrogen, are contributed by wastewater treatment plants, septic systems, and land use activities such as lawn fertilizing. Excessive nutrients threaten the ecological balance of the estuaries and thus the survival of shellfish populations. Finally, bacteria from failing septic systems, pet waste, or damaged sewer systems create a human health hazard in estuarine waters. Because shellfish filter great amounts of water to take in food and oxygen, they absorb contaminants from the water that accumulate in their flesh. Therefore, a watershed that flushes large amounts of contaminants downstream will deliver many of these contaminants to shellfish and reduce their numbers or often make them unsafe to eat. It is this close relationship between coastal watershed function and shellfish health that caused the New Hampshire Estuaries Project (NHEP), and many partnering agencies, to monitor shellfish in New Hampshire and make their restoration and maintenance a priority. The NHEP Manage- ment Plan includes many strategies that improve water quality throughout the watershed that will in turn improve shellfish populations and open more harvesting areas

Understanding and Applying Ecological Principles in Cities

Renaturing cities requires a thorough understanding of how plants and animals interact with the urban environment and humans. But cities are a challenging environment for ecologists to work in, with high levels of heterogeneity and rapid rates of change. In addition, the hostile conditions often found in cities mean that each city, and region of a city, can have their own unique geographical context. In this chapter, we contrast urban ecological research in the UK and Brazil, to demonstrate the challenges and approaches needed to renature cities. In so doing, we provide a platform for global transferability of these locally contextualised approaches. The UK has a long history of urbanisation and, as a result of increasing extinction debts over 200 years, well-established urban ecological research. Research is generally focused on encouraging species back into the city. In contrast, Brazil is a biodiversity hotspot with relatively rich urban flora and fauna. This rich ecosystem is imperilled by current rapid urbanisation and lack of support for urban nature by city-dwellers. By working together and transferring expertise, UK and Brazilian researchers stand a better chance of understanding urban ecological processes and unlocking renaturing processes in each location. We present one such method for applying ecological knowledge to cities, so-called Ecological Engineering, in particular by discussing ecomimicry—the adaptive approach needed to apply global ecological principles to local urban challenges. By reading the ecological landscape in which urban developments sit and applying tailored green infrastructure solutions to new developments and greenspaces, cities may be able to reduce the rate at which extinction debt is accumulated