24,485 research outputs found
Target Detection Using Fractal Geometry
The concepts and theory of fractal geometry were applied to the problem of segmenting a 256 x 256 pixel image so that manmade objects could be extracted from natural backgrounds. The two most important measurements necessary to extract these manmade objects were fractal dimension and lacunarity. Provision was made to pass the manmade portion to a lookup table for subsequent identification. A computer program was written to construct cloud backgrounds of fractal dimensions which were allowed to vary between 2.2 and 2.8. Images of three model space targets were combined with these backgrounds to provide a data set for testing the validity of the approach. Once the data set was constructed, computer programs were written to extract estimates of the fractal dimension and lacunarity on 4 x 4 pixel subsets of the image. It was shown that for clouds of fractal dimension 2.7 or less, appropriate thresholding on fractal dimension and lacunarity yielded a 64 x 64 edge-detected image with all or most of the cloud background removed. These images were enhanced by an erosion and dilation to provide the final image passed to the lookup table. While the ultimate goal was to pass the final image to a neural network for identification, this work shows the applicability of fractal geometry to the problems of image segmentation, edge detection and separating a target of interest from a natural background
Effect of osmotic potential of activator solution and temperature on viability and vigour of wheat seed
Experiment was conducted to investigate if seed priming with polyethylene glycol (PEG) activator solutions affects the viability and vigour of deteriorating wheat (Triticum aestivum L. cv. Caxton) seed lot. Seeds were subjected to PEG priming solutions with varying osmotic potentials (-1, -2, -3 MPa) at temperatures of 15 or 20°C for 6, 12, 18 or 24 h and compared to the non-primed control. Highest germination percentage at first and final count, length of plumule and dry weight of seedling were all associated with Treatment 1 MPa/20°C/6 h (92%, 94%, 9.2 cm, 0.0133 mg, respectively) compared to the control (82.5%, 86%, 7.8 cm, 0.0112 mg, respectively). The best values of coefficient of velocity of germination (CVG), mean germination time (MGT) and germination rate index (GRI) were associated with Treatment 2 MPa/15°C/24 h. There were significant interactions between the factors under study and whilst most positive effects decreased with incubation time the opposite was true at 15°C Treatment 2 MPa where an initial decrease in germination after 6 h was restored with longer incubation times. Significant correlations were found between most of the characteristics under study although these did not always account for a high percentage of variation but CVG and MGT were very highly correlated. It was concluded that, 6 h in Treatment 1 MPa PEG at a temperature of 20°C resulted in significantly improved germination percentage whilst 24 h Treatment 2 MPa at 15°C was optimal for the highest CVG and MGT. The highest speed of germination was not associated with the highest germination percentage
Information technology professionals and the new-rich middle class in Chennai (Madras)
Since 1991, when the policy of economic liberalisation began in earnest, the size and prosperity of India's middle class have grown considerably. Yet sound sociological and ethnographic information about its social structure and cultural values is still sparse, and as André Béteille comments: ‘Everything or nearly everything that is written about the Indian middle class is written by middle-class Indians…[who] tend to oscillate between self-recrimination and self-congratulation’. The former is exemplified by Pavan Varma's The Great Indian Middle Class (1998), which excoriates this class for its selfish materialism and the ‘retreat from idealism’ that was manifest in the smaller, ‘traditional middle class’ of the earlier, post-independence period. A good example of the opposite tendency is Gurcharan Das's India Unbound (2002), which celebrates ‘the rise of a confident new middle class’Das's diagnosis of what has changed is actually very similar to Varma's, but he insists that the new middle class is no ‘greedier’ than the old one, and the ‘chief difference is that there is less hypocrisy and more self-confidence
Traditional vocations and modern professions among Tamil Brahmans in colonial and post-colonial south India
Since the nineteenth century, Tamil Brahmans have been very well represented in the educated professions, especially law and administration, medicine, engineering and nowadays, information technology. This is partly a continuation of the Brahmans’ role as literate service people, owing to their traditions of education, learning and literacy, but the range of professions shows that any direct continuity is more apparent than real. Genealogical data are particularly used as evidence about changing patterns of employment, education and migration. Caste traditionalism was not a determining constraint, for Tamil Brahmans were predominant in medicine and engineering as well as law and administration in the colonial period, even though medicine is ritually polluting and engineering resembles low-status artisans’ work. Crucially though, as modern, English-language, credential-based professions that are wellpaid and prestigious, law, medicine and engineering were and are all deemed eminently suitable for Tamil Brahmans, who typically regard their professional success as a sign of their caste superiority in the modern world. In reality, though, it is mainly a product of how their old social and cultural capital and their economic capital in land were transformed as they seized new educational and employment opportunities by flexibly deploying their traditional, inherited skills and advantages
The art of being human : a project for general philosophy of science
Throughout the medieval and modern periods, in various sacred and secular guises, the unification of all forms of knowledge under the rubric of ‘science’ has been taken as the prerogative of humanity as a species. However, as our sense of species privilege has been called increasingly into question, so too has the very salience of ‘humanity’ and ‘science’ as general categories, let alone ones that might bear some essential relationship to each other. After showing how the ascendant Stanford School in the philosophy of science has contributed to this joint demystification of ‘humanity’ and ‘science’, I proceed on a more positive note to a conceptual framework for making sense of science as the art of being human. My understanding of ‘science’ is indebted to the red thread that runs from Christian theology through the Scientific Revolution and Enlightenment to the Humboldtian revival of the university as the site for the synthesis of knowledge as the culmination of self-development. Especially salient to this idea is science‘s epistemic capacity to manage modality (i.e. to determine the conditions under which possibilities can be actualised) and its political capacity to organize humanity into projects of universal concern. However, the challenge facing such an ideal in the twentyfirst century is that the predicate ‘human’ may be projected in three quite distinct ways, governed by what I call ‘ecological’, ‘biomedical’ and ‘cybernetic’ interests. Which one of these future humanities would claim today’s humans as proper ancestors and could these futures co-habit the same world thus become two important questions that general philosophy of science will need to address in the coming years
Deer reduce habitat quality for a woodland songbird: evidence from settlement patterns, demographic parameters, and body condition.
Understanding avian responses to ungulate-induced habitat modification is important because deer populations are increasing across much of temperate Europe and North America. Our experimental study examined whether habitat quality for Blackcaps (Sylvia atricapilla) in young woodland in eastern England was affected by deer, by comparing Blackcap behavior, abundance, and condition between paired plots (half of each pair protected from deer). The vegetation in each pair of plots was the same age. The Blackcap is an ideal model species for testing effects of deer on avian habitat quality because it is dependent on dense understory vegetation and is abundant throughout much of Europe. We compared timing of settlement, abundance, age structure (second-year vs. after-second-year), and phenotypic quality (measured as a body condition index, body mass divided by tarsus length) between experimental and control plots. We used point counts to examine Blackcap distribution, and standardized mist netting to collect demographic and biometric data. Incidence of singing Blackcaps was higher in nonbrowsed than in browsed plots, and singing males were recorded in nonbrowsed plots earlier in the season, indicating earlier and preferential territory establishment. Most Blackcaps, both males and females, were captured in vegetation prior to canopy closure (2–4 years of regrowth). Body condition was superior for male Blackcaps captured in nonbrowsed plots; for second-year males this was most marked in vegetation prior to canopy closure. We conclude that deer browsing in young woodland can alter habitat quality for understory-dependent species, with potential consequences for individual fitness and population productivity beyond the more obvious effects on population density
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Changing positions: The Sexual Politics of A Women’s Field Hockey Team 1986-1996
Despite a huge expansion in the literature on individual aspects of sexual identity and sexuality, and the growth of studies on women in sport, there are still relatively few investigations into women’s sporting and sexual subcultures. In addition, practical difficulties frequently preclude the adoption of longitudinal research designs when studying sport groups. This research describes the micro-dynamics of a particular women’s field hockey team, tracing the shifting composition of the team from predominantly heterosexual to almost entirely lesbian over the ten year period 1986-1996. A retrospective, longitudinal design was used: data from semi-structured interviews with 26 players were matched against data depicting the changing distribution of heterosexual and lesbian players during the ten year period. Two major findings emerge: first, that the women’s sexual identities were more fluid and complex than most of the literature on women in sport implies. Secondly, the status system of the club was more strongly influenced by organisation sexuality than it was by structural tradition. Consequently the status system changed from one based on structure (i.e. years of experience in the club) to one based on culture (i.e. identity as a lesbian organisation) as the number of self-identified lesbians increased beyond 38%
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Energy Projects in Milton Keynes: Energy Consultative Unit Progress Report 1976-1981
The Energy Consultative Unit was a joint Open University/MKDC body set up by Professor Jake Chapman, founder of the OU Energy Research Group. This report describes the work carried out on energy-related projects in Milton Keynes over the period 1976-1981, many of them involving the Open University. After a short explanation of how energy is used in the UK, the report introduces the Energy Consultative Unit projects and summarises the main conclusions drawn from the Unit's work. It then describes the projects on which the Unit has worked and summarises other energy projects under way in the new city. It does not go into the projects in detail, but there are a number of technical reports available for people who want to study them in more depth, and these are listed in the back of the report. The projects represent the work of a considerable number of people and a list of acknowledgements, indicating who should be contacted for further information, is also set out at the back of the report
Nuclear weak interaction rates in primordial nucleosynthesis
We calculate the weak interaction rates of selected light nuclei during the
epoch of Big Bang Nucleosynthesis (BBN), and we assess the impact of these
rates on nuclear abundance flow histories and on final light element abundance
yields. We consider electron and electron antineutrino captures on 3He and 7Be,
and the reverse processes of positron capture and electron neutrino capture on
3H and 7Li. We also compute the rates of positron and electron neutrino capture
on 6He. We calculate beta and positron decay transitions where appropriate. As
expected, the final standard BBN abundance yields are little affected by
addition of these weak processes, though there can be slight alterations of
nuclear flow histories. However, non-standard BBN scenarios, e.g., those
involving out of equilibrium particle decay with energetic final state
neutrinos, may be affected by these processes.Comment: 10 pages, 6 figure
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