82 research outputs found
Studies on the Pyrolysis of Composite Solid Propellants leading to Ignition
Studies on the pyrolysis leading to ignition of polystyrene (PS)/ammonium perchlorate (AP), polyvinyl chloride (PVC)/AP and polyphenol formaldehyde (PPF)/AP propellants revealed that the activation energy for the ignition strongly depends upon the binder. Double base propellants exhibit an empirical relationship between the ignition delay (~) and the oxidiser concentration; when the same equation is applied to composite solid propellants, the plot of In ~ vs In C (C=Concentration, %) yields a straight line with a knee corresponding to 65-70 per cent AP above which the dependence on ~ becomes less sensitive
Changes in the Calorimetric Value and Ignition Temperature of Composite Solid Propellants During Ageing-A Note
Calorimetric value and ignition temperature of carboxy terminated polybutadiene/ammonium perchlorate propellant decrease during accelerated ageing. The behaviour has been explained on account of binder loss and condensed phase reactions in the propellant matrix
An unusual congregation of organisms in the catches off Kovalam, Madras
The fishermen belonging to Kovalam had a hectic activity in harvesting huge quantities of fish from the Kovalam bay from 26-8-'87 to 4-9-'87. Fishermen employed all available gears for catching the fish and prawns. According to them, this was due to the appearance of 'Vandal thanneer' or turbid water close to the shore. The present account embodies the results of the observations made on this unusual phenomenon
Marine fisheries of the south-east coast of India during 2008
The south-east coast of India comprising the
states of Andhra Pradesh, Tamil Nadu and
Pondicherry have a total coastline of 2050 km which
is 34% of the total coastline of the country. This region
is more diverse with respect to the number of species
that are landed. In 2007, it was observed that 499
species were landed in Tamil Nadu, 294 in Andhra
Pradesh and 115 in Pondicherry
Implementing Fine/Medium Grained TLP Support in a Many-Core Architecture
Abstract. We believe that future many-core architectures should support a simple and scalable way to execute many threads that are generated by parallel programs. A good candidate to implement an efficient and scalable execution of threads is the DTA (Decoupled Threaded Architecture), which is designed to exploit fine/medium grained Thread Level Parallelism (TLP) by using a hardware scheduling unit and relying on existing simple cores. In this paper, we present an initial implementation of DTA concept in a many-core architecture where it interacts with other architectural components designed from scratch in order to address the problem of scalability. We present initial results that show the scalability of the solution that were obtained using a many-core simulator written in SARCSim (a variant of UNISIM) with DTA support
Coarse-grained reconfigurable array architectures
Coarse-Grained Reconfigurable Array (CGRA) architectures accelerate the same inner loops that benefit from the high ILP support in VLIW architectures. By executing non-loop code on other cores, however, CGRAs can focus on such loops to execute them more efficiently. This chapter discusses the basic principles of CGRAs, and the wide range of design options available to a CGRA designer, covering a large number of existing CGRA designs. The impact of different options on flexibility, performance, and power-efficiency is discussed, as well as the need for compiler support. The ADRES CGRA design template is studied in more detail as a use case to illustrate the need for design space exploration, for compiler support and for the manual fine-tuning of source code
Overview of marine fisheries in India during 2007
Fisheries sector in India plays an important role
in the country’s economy and it supports the livelihood
of millions of people. India is having 8,129 km of
coastal length with 2.02 million sq. km of Exclusive
Economic Zone (upto 200 m depth) and 0.452 million
sq. km of continental shelf area
Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases
The production of peroxide and superoxide is an inevitable consequence of
aerobic metabolism, and while these particular "reactive oxygen species" (ROSs)
can exhibit a number of biological effects, they are not of themselves
excessively reactive and thus they are not especially damaging at physiological
concentrations. However, their reactions with poorly liganded iron species can
lead to the catalytic production of the very reactive and dangerous hydroxyl
radical, which is exceptionally damaging, and a major cause of chronic
inflammation. We review the considerable and wide-ranging evidence for the
involvement of this combination of (su)peroxide and poorly liganded iron in a
large number of physiological and indeed pathological processes and
inflammatory disorders, especially those involving the progressive degradation
of cellular and organismal performance. These diseases share a great many
similarities and thus might be considered to have a common cause (i.e.
iron-catalysed free radical and especially hydroxyl radical generation). The
studies reviewed include those focused on a series of cardiovascular, metabolic
and neurological diseases, where iron can be found at the sites of plaques and
lesions, as well as studies showing the significance of iron to aging and
longevity. The effective chelation of iron by natural or synthetic ligands is
thus of major physiological (and potentially therapeutic) importance. As
systems properties, we need to recognise that physiological observables have
multiple molecular causes, and studying them in isolation leads to inconsistent
patterns of apparent causality when it is the simultaneous combination of
multiple factors that is responsible. This explains, for instance, the
decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference
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