Studying the Imaging Characteristics of Ultra Violet Imaging Telescope (UVIT) through Numerical Simulations

Ultra-Violet Imaging Telescope (UVIT) is one of the five payloads aboard the Indian Space Research Organization (ISRO)'s ASTROSAT space mission. The science objectives of UVIT are broad, extending from individual hot stars, star-forming regions to active galactic nuclei. Imaging performance of UVIT would depend on several factors in addition to the optics, e.g. resolution of the detectors, Satellite Drift and Jitter, image frame acquisition rate, sky background, source intensity etc. The use of intensified CMOS-imager based photon counting detectors in UVIT put their own complexity over reconstruction of the images. All these factors could lead to several systematic effects in the reconstructed images. A study has been done through numerical simulations with artificial point sources and archival image of a galaxy from GALEX data archive, to explore the effects of all the above mentioned parameters on the reconstructed images. In particular the issues of angular resolution, photometric accuracy and photometric-nonlinearity associated with the intensified CMOS-imager based photon counting detectors have been investigated. The photon events in image frames are detected by three different centroid algorithms with some energy thresholds. Our results show that in presence of bright sources, reconstructed images from UVIT would suffer from photometric distortion in a complex way and the presence of overlapping photon events could lead to complex patterns near the bright sources. Further the angular resolution, photometric accuracy and distortion would depend on the values of various thresholds chosen to detect photon events.Comment: Submitted to PASP, 16 Pages, 9 figure

E1−E2E1-E2 interference in the Coulomb dissociation of 8^8B

We investigate the effects arising out of the $E1 - E2$ interference in the Coulomb dissociation of $^8$B at beam energies below and around 50 MeV/nucleon. The theory has been formulated within a first order semiclassical scheme of Coulomb excitation, in which both the ground state and the continuum state wave functions of $^8$B enter as inputs. We find that the magnitude of the interference could be large in some cases. However, there are some specific observables which are free from the effects of the $E1 - E2$ interference, which is independent of the models used to describe the structure of $^8$B. This will be useful for the analysis of the breakup data in relation to the extraction of the astrophysical factor $S_{17}(0)$.Comment: Revised version to appear in Physical Review

A Novel Survey Analysis on Energy-Aware Routing Protocols for Manet Applications

MANET system applications in today situation consumes larger amounts of energy this energy becomes an important parameter and scarce resource in MANETS This energy consumption has to be reduced and harvested in the communication devices for efficient usage of energy and power Different energy aware and harvesting strategies have been devised using various protocols to achieve the reduction and minimised usage of the available energy and power resources This paper surveys and illustrates the differences of various Energy aware Routing Protocol used in MANETS based on the matrices used These protocols provide some awareness in optimizing the Energy and Power Resources and limit the consumption when nodes are idle This intern increases the life time of the node and improves the performance widely investigating the energy efficiency protocols for adhoc infrastructure less MANET environmen

Impact of Chinese engines in the marine fishing sector of Kerala

Impact of Chinese engines in the marine fishing sector of Keral

Constraint analysis on the impediments faced by Indian seafood exporters

Among the leading non traditional exports, fish and fishery products play a prominent role contributing significantly to the success of India's export effort to bridge the yawning trade gap of India.They have become one of the major foreign exchange earners in the agricultural and a1lied sectors of India in the recent years. Starting from mere scraps in the pre independence period, it is a saga of steady striking and sustained growth that the industry had recorded raising India's status and prestige and securing for her a respectable position among the maritime nations of the worl

Subsidies in Indian fisheries-Methodological issues and implications for the future

Subsidies are financial contributions made by Government or public bodies which provide a private benefit. Westlund (2003) defined fisheries subsidies as “government actions or inactions that are specific to the fisheries industry and that modify – by increasing or decreasing – the potential profits by the industry in the short, medium or long-term”. World attention was drawn to the scale of the global fisheries crisis and also the extent of fishery subsidies in 1992 with the publication of an FAO report, Marine Fisheries and the Law of the Sea: A Decade of Change. The adverse effect of subsides depend on the existing management regime and the bioeconomic conditions of the fishery. Subsidies lower the cost of harvest and raise the effective price of fish. As a management tool, cost-reducing or profit-increasing subsidies may result in increased productive efforts and hence considered as harmful through over exploitation of fish resources and unsustainable harvesting

Emission of Green House Gases from Grasslands and their Mitigation

The concentrations of green house gases (GHG) in the atmosphere began in pre-industrial times and it continues to increase. This could result into an alarming increase in temperature of up to 5.4 oC by year 2100 due to a net global annual GHG emission of H 4.5-6.5 Gt C equivalent. About 18% of the world’s GHG are contributed by livestock and related activities on grasslands that are spread over almost 35 million Km2.These grasslands give livelihood to over a billion people most of who are poor. Twenty to 70% of the land surface area is degrading often due to overgrazing caused by increased demand for meat and milk, among other factors. A right set of policies that incentivises appropriate management of the grasslands have the potential to reduce up to 30% of the GHG globally. This can be achieved by mainly focussing on reduction in deforestation for pastures, silvo-pastoral improvements and reduction in enteric fermentation in animals, and appropriate manure and fertilizer management, especially on extensive grasslands. Reduction in GHG emissions will also depend upon the level of resource use efficiencies achieved, added intensification to reduce pressure on grasslands, and success or failure of appropriate market and regulatory policy interventions

Assessing the consumer preferences using Conjoint Analysis: An Application in Fisheries Sector

Assessing the consumer preferences using Conjoint Analysis: An Application in Fisheries Secto

Environmental and social issues in coastal aquaculture

Aquaculture has grown rapidly in the recent years and has promise for further potential growth. This rapid expansion was possibly because of the growing demand for aquatic products and the failure of the global capture fishery, which has been exploited, to or beyond its potential. When the global catch statistics remains standstill between 80-100 million metric tons per year, the global aquaculture production is registering an overwhelming annual growth of 8-14% producing between 20-25 million tons per year. Of the aquaculture practices, coastal shrimp farming has registered the maximum growth of about 400% in the last decade. The two factors resulting to its boom were the increasing demand for Indian shrimp and the improved farming technique

Climate change world and your role

Earth’s climate is always changing. In the past, it has gone through warmer and cooler periods which last for thousands of years. This long term pattern of weather conditions (temperature, air pressure, humidity, precipitation, sunshine, cloudiness, and winds) prevailing in an area is the Climate change which is the most furious issue of the present world. Climate change is change in the earth’s overall climate or a long term change in the weather pattern of a region for a considerable period of time eg: change in the earth’s global temperature, or its typical precipitation pattern. It can also be any significant long-term change in the expected patterns of average weather of a region across a considerable period of time