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Periodicity of quasar and galaxy redshift
No full textContext. An approach for studying the large-scale structure of the Universe lies in the detection and analysis of periodicity of redshift values of extragalactic objects, galaxies, and quasi stellar objects (QSO), in particular. Moreover, the hypothesis of the existence of multiple periodicities in the redshift distributions deserves exploration. The task is compounded by the presence of confounding effects and measurement noise.
Aims. Studies of periodicity detection in redshift values of extragalactic objects obtained from the Sloan Digital Sky Survey (SDSS)
have been conducted in the past, largely based on the Fourier transform. The present study aims to revisit the same thing using the
singular value decomposition (SVD) as the primary tool.
Methods. Periodicity detection and the determination of the fundamental period have been performed using a standard spectral
approach as well as a SVD-based approach for a variety of simulated datasets. The analysis of the quasar redshift data from DR12
and galaxy redshift dataset of DR10 from SDSS data has been carried out.
Results. A wide range of periodicities are observed in different redshift ranges of the quasar datasets. For redshifts greater than 0.03,
a period length of 0.2094 was determined while periodicities of 0.1210 and 0.0654 were obtained for redshift ranges (0.03,1) and
(3,4), respectively. Twin periodicities of 0.1153 and 0.0807 were obtained for the redshift range (1,3). Determining the ranges to be
examined has been done based on histogram computation; the binwidths of which have been obtained by employing a kernel density
estimation. The redshift sequence for the galaxy samples exhibits a somewhat different nature, but still contains periodic components.
Twin periodicities of 0.0056 and 0.0079 were observed for a redshift range greater than 0.03.
Conclusions. Galaxy and quasar redshift values form sequences, which are not only discrete in amplitude but also contain periodic
components. The superiority of the singular value decomposition method over the spectral estimation approach, in redshift periodicity
analysis especially from the point of view of robustness, is demonstrated through simulations. The existence of periodicity for quasar
and galaxy families is thus firmly established, lending further support to the Hoyle-Narlikar variable mass theory
The Impact of Development on Social Conflicts-Case Studies of Intra-Family and Inter-Group Strife in Two Villages in Kerala
No full textThe escalation of individual cases of women’s demand for equality and personal freedom into intra-community and inter-community conflicts are not unknown. As more women have begun to assert themselves as individuals, citizens and workers in the contemporary context of globalised development, the link between gender relations and social conflicts are only likely to strengthen. However, the existing theorisations have largely under-examined the role of gender and family in shaping intra-community and inter-community conflicts because of the complete analytical separation between the private and public spheres. To understand the impact of diverse development processes on the everyday interactions between intra-family gender relations and social conflicts, mixed-methods field research was conducted in two villages in Kerala with diverse development experiences. The study focused on the changes in two sets of interactions - between work and family, and between family and community- by analysing gender relations within and across these spheres. The study finds that the transition from a low-income economy to a remittance-dependent consumerist society has generated new crises, inequalities, opportunities and aspirations in contemporary Kerala. The responsibilities and burdens of managing the crises and negotiating aspirations under these contexts of immense social change have increasingly fallen on women. Women’s labour has emerged as an important resource for globalising capital. Development policies and welfare programs target women as primary agents through whom welfare resources are transferred to families. Women play a vital role in the survival, resilience and upward mobility of families in the contemporary context. With this expansion of women’s economic roles and a simultaneous weakening of men’s ability to be breadwinners, the traditional bases for masculine power and identity within the family are being undermined. It is under these circumstances of altered intra-family gender dynamics that men turn to community and political organisations to restore their diminished status. Community organisations in Kerala have always been major sources of economic, social, political and affective support for its members. Consequently, leadership positions in these organisations are associated with high status. As men dominate these resourceful organisations, their status as household heads and active community members is reinforced undermining the important contributions women make in the work and home spheres. The masculinised community and political organisations use gender as an instrument to control women and mobilise them for various communitarian projects including inter-group conflicts
Mapping the life trajectories of women scientists in India: successes and struggles
Get PDFThis article discusses the findings of a research report titled ‘Capturing diversity: a comprehensive
report on women in science and engineering in India’. By mapping the life trajectories of 130 women
scientists of India, the article highlights their successes and struggles at different levels of their
lives in order to have a career in science
Space Newsletter: Science, Technology, Application 2(2)
Get PDFToday we have several Earth Observation Satellites
launched by various agencies acquiring and sending huge
environmental data like pollutants, population movement,
transportation movement, construction on ground, weather
conditions, climatic condition, oceanic conditions, chlorophyll
etc. This kind of data is available since 1972 with the
introduction of Landsat series satellites jointly by NASA and
US Geological Survey. Now, the ongoing research is on how
to integrate analytical technologies like ML, computational
epidemiology, CFD etc blended with innovation with the
uninterruptedly available satellite data to predict the
outbreak of unknown diseases. This will help the policy
makers to make informed decisions for the wellbeing of
general public
Assembling Amaravati: speculative accumulation in a new Indian city
Get PDFThe paper explores processes of speculative accumulation through land in the making of a new city in Andhra Pradesh, southern India. Rather than analysing the Amaravati plan as an example of neoliberal urbanization or ‘accumulation by dispossession’, it examines how the project is unfolding on the ground by situating it within the region’s ‘vernacular capitalism’ centred on land and finance capital. The paper maps the processes of speculative accumulation through which value is extracted from land by diverse actors, and describes the practices of calculation, investment and negotiation employed by local landowners to manage their uncertain futures and to insert themselves as ‘stakeholders’ in the development of the new city. The Amaravati case reflects the deepening entanglement of transnational and provincial circuits of capital in post-liberalization India
Is Agrarian Resilience Limited to Agriculture? Investigating the “Farm” and “Non-Farm” Processes of Agriculture Resilience in the Rural
No full textWith 76% of the total main workforce in agriculture and more than 50% small and medium landowning households, the village provides an important case study for understanding agrarian resilience. The conceptualisation of resilience has been majorly confined to a system or a territorial boundary. Agrarian resilience too is commonly assumed to be driven by forces within the agriculture and the rural. i.e. land ownership remains constant, the labour of the peasantry is spatially limited to agriculture, the capital is generated within agriculture and the networks and skills of the peasantry is also confined to agriculture. This has underscored the role of factors and processes working outside the agriculture in conceptualising agrarian resilience. While the primacy of the agrarian processes cannot be denied, there are often processes working outside an agrarian system that can also enable resilience. i.e. the rural workforce can diversify its labour outside agriculture in the urban non-farm sector, capital can also be generated from sources outside the agriculture. In this context, using the case study of a village dominated by small and medium landowning households in the Patiala district of Punjab in India, the paper shows that resilience is driven by processes both within and outside agriculture
Performance Evaluation of an Open Thermochemical Energy Storage System Integrated with Flat Plate Solar Collector
No full textIn this study, the performance of an open thermochemical energy storage (TCES) system integrated with a flat plate solar collector is evaluated using a simplified dynamic model for space heating applications, considering a charging phase during the summer daytime and a discharging phase during the winter night. For charging and discharging operations, the time-varying solar flux (DNI) and ambient conditions in Pune, India is used. Simplified energy balance equations for the reactive packed bed and the flat plate solar collector are developed and validated against the previous reported works. The effects of the energy density and the aspect ratio of the reactive packed bed on the performance of the TCES system are evaluated using a non-dimensional parameter , which is the ratio of thermal power extracted/stored to the power required to blow air through the reactive packed bed. An increase in reactive packed bed energy density by 16.66% is found to decrease the time-averaged value of by 63.97% and 48.06%, respectively, for charging and discharging phases. A four-fold increase of aspect ratio of the reactive packed bed is found to increase the time-averaged value of by 6.20 times and 6.35 times during the charging and discharging phases, respectively
Predicting the performance of a photovoltaic system in the island nation, Mauritius
No full textExistence of microclimatic conditions in tropical island poses a challenge to integrate a greater share of renewable energy, more specifically solar energy into the power grid. Because of the high humidity and sudden cloud coverage, the power output from solar photovoltaic (SPV) plants is severely affected. In this manuscript, the performance results of a study carried out on a 15.2 MW solar photovoltaic (SPV) plant in the island nation Mauritius are analyzed. The net annual yield was 22,162 MWh. This plant has prevented 22,162 metric tonnes of CO2 being released into the atmosphere. A model is deduced to forecast the yield from the SPV plants at that location. The grid operator, the National Central Electricity Board, needs to know a priori, the energy mix for the subsequent few days so that the level of operation of fossil fuel-fired thermal plants can be tuned accordingly to minimize the environment pollution of this pristine island