2,908 research outputs found

    Model based methodology development for energy recovery in ash heat exchange systems

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    Flash tank evaporation combined with a condensing heat exchanger can be used when heat exchange is required between two streams and where at least one of these streams is difficult to handle (in terms of solid particles content, viscosity, pH, consistency etc.). To increase the efficiency of heat exchange, a cascade of these units in series can be used. Heat transfer relationships in such a cascade are very complex due to their interconnectivity, thus the impact of any changes proposed is difficult to predict. In this report, a mathematical model of a single unit ash tank evaporator combined with a condensing heat exchanger unit is proposed. This model is then developed for a chain of the units. The purpose of this model is to allow an accurate evaluation of the effect and result of an alteration to the system. The resulting model is applied to the RUSAL Aughinish Alumina digester area

    Yang-Mills theory for bundle gerbes

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    Given a bundle gerbe with connection on an oriented Riemannian manifold of dimension at least equal to 3, we formulate and study the associated Yang-Mills equations. When the Riemannian manifold is compact and oriented, we prove the existence of instanton solutions to the equations and also determine the moduli space of instantons, thus giving a complete analysis in this case. We also discuss duality in this context.Comment: Latex2e, 7 pages, some typos corrected, to appear in J. Phys. A: Math. and Ge

    Some observations on the possibilities of culture of the Indian sand whiting Sillago sihama (Forskal) in brackish waters

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    Indian sand whiting, Sillago sihama (Forskal) forms a dominant species in the estuarine fish catches during the south-west monsoon when they are in great demand and fetch a high price as sea fishing remains suspended due to rough weather conditions. The paper deals with preliminary observations on certain aspects of the biology of the fish related to its culture. The ability of the species to withstand very wide raoges of salinity makes it suitable for culture io both brackish and fresh waters

    Quantitative abundance of amphipods around Andaman-Nicobar Islands

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    The present study deals with the quantitative distribution and abundance of amphipods of the Andaman Sea in time and space, based on the zooplankton samples collected during the cruises 46- 73 of FORV Sagar Sampada during 1988-1990. Mean number of amphipods (no/1000 m ) reached the maximum of 1763 in January and the minimum of 315 in July. The seasonal density was maximum during the northeast monsoon and minimum for the southwest monsoon and their mean numbers were estimated as 812 and 463/1000 m respectively. In general, they were abundant in the region where the station depths ranged between 50 and 100 m with the mean estimated as 800/1000 m of water. Analysis of day and night samples did not show any remarkable variation. The distribution and abundance of amphipods in relation to time and space are discussed in the paper

    Extensive Review on Laminated Bus Bar for Low and High Power Applications

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    This paper explains about wide range of applications for Laminated Bus Bar used for high and low power applications. Authors also explains ways to effective utilize laminated bus bar when compared to conventional bus bar. Laminated bus bars are designed with low stray inductance and high capacitance with a uniform current distribution in conducting plate. Parameters like Length, Width, material thickness and other miscellaneous parameters effect Laminated bus bar performance. With a proper design of Laminated bus bar it can best utilized, laminated bus bar are suitable for many low and high power applications which are discussed in this paper. Replacing conventional bus bar with laminated bus bar additional advantages are achieved like lighter weight, less space and lower maintenance

    Estimation of ASO titer as an indicator of streptococcal infection precipitating acute adenolymphangitis in brugian lymphatic filariasis

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    Recurrent episodes of acute adenolymphangitis (ADL) are important clinical manifestations of lymphatic filariasis which contribute significantly to the progression of lymphedema. It is increasingly being recognized that secondary bacterial infections play an important role in the etiology of ADL. We examined the role of streptococcal infection as a precipitating factor of ADL in brugian filariasis, by determining the anti-streptolysin O (ASO) titers and by isolating the causative organism wherever possible. The study population consisted of 30 patients with filariasis related ADL (Group A), 30 patients with chronic filarial edema (Group B) and 60 age and sex matched healthy adults (Group C). ASO titer was estimated by the latex agglutination method at the time of entry into the study, at the 15th day and at 3,6 and 12 months. ASO titers were persistently elevated in 90% of patients in Group A and a portal of entry for bacterial infection was detected in all of these patients. In Group B only six patients had persistently elevated ASO titers. These patients had grade III lymphedema and three of them had monilial infections in the affected limb. In the control group none had persistently elevated ASO titers. The elevated ASO titers and the detection of a site of entry for bacteria in patients with ADL supports a streptococcal etiology for this condition

    Bayesian State-space Implementation of Schaefer Production Model for Assessment of Stock Status for Multi-gear Fishery

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    Knowing the status of marine fish stock is of utmost importance to develop management strategies for sustainable harvest of marine fishery resources. A widely accepted approach towards this is to derive sustainable harvest levels using time series data on fish catch and fishing effort based on fish stock assessment models like Schaefer’s model that describe the biomass dynamics. In India, the marine fishery is of complex multi-species nature where in different species are caught by a number of fishing gears and each gear harvests a number of species making it difficult to obtain the fishing effort corresponding to each fish species. Since the capacity of the gears varies, the effort made to catch a resource cannot be considered as the sum of efforts expended by different fishing gears. Hence, it demands the importance of effort standardisation for making use in stock assessment models. This paper describes a methodology for the standardization of fishing efforts and assessing fish stock status using Bayesian state-space implementation of the Schaefer production model (BSM). A Monte Carlo based method namely Catch-Maximum Sustainable Yield (CMSY), has also been used for estimating fisheries reference points from landings and a proxy for biomass using resilience of the species. The procedure has been illustrated with data on Indian mackerel (Rastrelliger Kanagurta) collected from the coastal state of Andhra Pradesh, India during 1997-2018. Maximum Sustainable Yield (MSY) of Indian mackerel for Andhra Pradesh has been estimated. A comparison between both CMSY and BSM methods have been made and found that the estimates are in close agreements
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