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GASP. XV. A MUSE view of extreme ram-pressure stripping along the line of sight: Physical properties of the jellyfish galaxy JO201
We present a study of the physical properties of JO201, a unique disc galaxy with extended tails undergoing extreme ram-pressure stripping (RPS) as it moves through the massive cluster Abell 85 at supersonic speeds mostly along the line of sight. JO201 was observed with multi-unit spectroscopic explorer as part of the GASP programme. In a previous paper (GASP II) we studied the stellar and gas kinematics. In this paper we present emission-line ratios, gas-phase metallicities, and ages of the stellar populations across the galaxy disc and tails. We find that while the emission at the core of the galaxy is dominated by an active galactic nucleus (AGN), the disc is composed of star-forming knots surrounded by excited diffuse gas. The collection of star-forming knots presents a metallicity gradient steadily decreasing from the centre of the galaxy outwards, and the ages of the stars across the galaxy show that the tails formed ? 109 yr ago. This result is consistent with an estimate of the stripping time-scale (?1 Gyr), obtained from a toy orbital model. Overall, our results independently and consistently support a scenario in which a recent or ongoing event of intense RPS acting from the outer disc inwards, causes removal and compression of gas, thus altering the AGN and star formation activity within and around the galaxy. 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. -
Effect of Coriolis force on Rayleigh-Bard convection with internal heat generation
The objective of this paper is to analyze the influence of the Coriolis force and internal heat source on Rayleigh-Bard convection in a Boussinesquian fluid of depth d. A linear theory which is oriented towards the normal mode analysis technique is used for this mono-diffusive convection in order to find the criteria for the onset of Rayleigh-Bard convection. The eigenvalue of the said problem was obtained by the use of the Galerkin method in the cases of rigid-rigid, rigid-free, and free-free velocity boundary combinations considering the isothermal and adiabatic temperature boundaries that determine the stability of the system. The effects of various parameters, Taylor number and the internal Rayleigh number are put under consideration only for stationary convection. Treating Taylor number as a critical parameter, shown that it plays a major role in stabilization of the system in case of any particular infinitesimal disturbance. The destabilization of the system has been possible with rotation by treating internal Rayleigh numbers as a critical parameter since the increase in values of the internal Rayleigh number advances the onset of convection. Oscillatory convection seems highly improbable as the scaled frequency of oscillation remains less than 0 for all combinations of Prandtl number, internal Rayleigh number, and Taylor number. 2019, Accent Social and Welfare Society. All rights reserved. -
Locating Indian universities in knowledge societies: A critique
Knowledge societies characterize a defining feature of the present era. Veering away from their initial connotation of scientific temper and reasoning, today, they assume a new meaning in which the basis of economy, polity, and social action is knowledge. In the post-capitalist, post-industrial societies, knowledge has become the foundation of industrial productivity and social wellbeing. The crux of knowledge production has been shifting from the traditional disciplinary contexts promoted by academic interests in the universities to its applications for better productivity and wellbeing. Nevertheless, productivity and usefulness are accorded an epistemological appeal in defining what counts as knowledge. In this context, the present paper discusses the changes in knowledge production and dissemination processes in knowledge societies and their implications for universities in India. 2019 Journal of Dharma: Dharmaram Journal of Religions and Philosophies (DVK, Bangalore). -
Us and India: Emerging offshore balancing in Asia
The US and India have become closer in recent times. Compared with the last century, the relationship between the two countries is in steady growth. Under both the Bush and Obama administrations, and now the Trump administration too, India is receiving significant importance in US strategic policy toward the IndoPacific. Indias emergence as a credible power in the Indian Ocean region has brought both countries much closer. The relationship has also steadily progressed as result of Chinas emergence as a potential hegemon in Asia. The US faces difficulty in maintaining its preponderant position across the IndoPacific and requires strong allies in the region to help share the burden. In this regard, India could be the offshore balancer in Asia to counter Chinas emergence as a potential hegemon in the region. 2019 Taylor & Francis Group, LLC. -
Prediction of Answer Keywords using Char-RNN
Generating sequences of characters using a Recurrent Neural Network (RNN) is a tried and tested method for creating unique and context aware words, and is fundamental in Natural Language Processing tasks. These type of Neural Networks can also be used a question-answering system. The main drawback of most of these systems is that they work from a factoid database of information, and when queried about new and current information, the responses are usually bleak. In this paper, the author proposes a novel approach to finding answer keywords from a given body of news text or headline, based on the query that was asked, where the query would be of the nature of current affairs or recent news, with the use of Gated Recurrent Unit (GRU) variant of RNNs. Thus, this ensures that the answers provided are relevant to the content of query that was put forth. Copyright 2019 Institute of Advanced Engineering and Science. All rights reserved. -
RADON in GROUNDWATER of MAGADI TALUK, RAMANAGARA DISTRICT in KARNATAKA
Radon is a water-soluble radioactive noble gas produced from the alpha decay of 226Ra in uranium series. Its presence in drinking water and open air increases the risk of lung and intestinal cancers in human beings. In view of this, radon concentration in groundwater and its dose due to inhalation and ingestion to the population of Magadi taluk of Ramanagara district in Karnataka state, India was studied. The groundwater samples were analyzed for radon concentration using emanometry technique. The study showed that the radon concentration in this area varied from 27.4 1.0 to 167.5 3.9 Bq/L and the effective dose ranged from 104.2 2.7 to 636.2 11.0 ?Sv/a. The study also revealed that 95% of the 37 samples studied showed higher radon concentration compared to the UNSCEAR recommendation (40 Bq/L) and all the samples showed higher than the USEPA recommendation (11.1 Bq/L). Ten samples have concentration above the maximum permissible level prescribed by WHO (100 Bq/L). The groundwater samples are found to be slightly alkaline within the permissible limit of Indian Standards. 2018 The Author(s). Published by Oxford University Press. All rights reserved. -
Facile synthesis of novel antimony selenide nanocrystals with hierarchical architecture by physical vapor deposition technique
Stoichiometric antimony selenide (Sb 2 Se 3 ) nanocrystals have been successfully engineered by a facile physical vapor deposition method, employing a single precursor of polycrystalline Sb 2 Se 3 charge in a closed quartz ampoule under high vacuum without any foreign seed or extraneous chemical elements. This work underscores the efficacy of the vapor deposition process and provides synthetic strategies to scale down bulk Sb 2 Se 3 into novel nanostructures. The morphological evolution of the tailored architecture was examined on micro and nano size scales by scanning electron microscopy and high-resolution transmission electron microscopy. The intrinsic mechanism governing the nanostructure formation is revealed as layer-by-layer growth, related to the unique layered structure of Sb 2 Se 3 . The optical properties of the grown crystals were probed by UVvisNIR and photoluminescence tools. The band-gap values of the microfibers, nanorods, nanooctahedra and nanospheres estimated from UVvisNIR analysis are found to be 1.25, 1.47, 1.51 and 1.75 eV, respectively. Powder X-ray diffraction, energy-dispersive analysis by X-rays, X-ray photoelectron spectroscopy, Raman spectroscopy and photoluminescence studies confirmed the quality, phase purity and homogeneity of the as-grown nanostructures. The adopted physical vapor deposition method is thus shown to be a simple and elegant route which resulted in the enhancement of the band gap for the Sb 2 Se 3 samples compared with their counterparts grown by chemical methods. This approach has great potential for further applications in optoelectronics. International Union of Crystallography, 2019 -
Lattice thermal conduction in suspended molybdenum disulfide monolayers with defects
In this study, we investigated the effect of lattice defects comprising vacancies and boundaries on the lattice thermal conductivity (LTC), ? p , of suspended molybdenum disulfide monolayers (MLs) over a wide temperature range (1 < T < 500 K). Using the phonon Boltzmann formalism, the acoustic phonons were considered to be scattered by the sample and grain boundaries, isotopic impurities, vacancies, and other phonons via Umklapp and normal (N-) processes. ? p was evaluated using a modified Callaway model by considering the in-plane longitudinal acoustic and transverse acoustic phonons, and out-of-plane flexural acoustic phonon modes. We demonstrated the need to include the often neglected non-resistive N-processes when evaluating the LTC. Numerical calculations of the temperature dependence of the LTC for crystalline and polycrystalline MoS 2 MLs showed the dominance of sample-dependent scattering mechanisms at low temperatures (T < 100 K) and of phonon-phonon scattering at higher temperatures, where the N-processes played an important role. The effects of vacancies and boundaries were to alter the behavior and suppress the magnitude of the LTC. The suppression due to vacancies was greater in crystalline MLs with specular surfaces and in polycrystalline MLs with larger grain sizes. The calculations compared well with recent thermal conductivity data obtained for polycrystalline samples. The need for further investigations is suggested. 2018 Elsevier Ltd -
Handwritten tibetan character recognition using hidden markov model
The Tibetan language which is one of the four oldest and most original languages of Asia is elemental to Tibetan identity, culture and religion and it convey very specific social and cultural behaviors, and ways of thinking. The annihilation of the Tibetan language will have tremendous consequences for the Tibetan culture and hence it is important to preserve it. Tibetan language is mainly used in Tibet, Bhutan, and also in parts of Nepal and India. Tibetan script is devised based on the Devanagari model and Sanskrit based grammars. In this paper, a method for Tibetan handwritten character recognition based on density and distance feature detection is presents. To get a better classification result, images are converted into binary and noise removal is done by using Otzsos method. Features are extracted by normalizing the image based on distance and density of the pixel in the image. Finally, Hidden Markov Model is used for character classification. BEIESP. -
An investigation on structural, electrical and optical properties of GO/ZnO nanocomposite
Coupling of graphene oxide with metal oxide is an effective way to enhance the opto-electric properties of the composite. Herein, a hybrid structure of graphene oxide (GO) -Zinc oxide (ZnO) nanostructure was successfully designed and fabricated with varying concentrations of ZnO. The GO and ZnO nanoparticles were synthesized through Hummer's and simple precipitation method respectively. Structural and physiochemical properties were examined via X-ray powder diffraction, FTIR and UV-Vis spectroscopy. The XRD results of GO showed a peak at 2? of 12.02 with particles of size 6nm and inter layer spacing 0.87 nm. The XRD patterns of ZnO nanoparticles showed a hexagonal unit cell structure and the average dimension of the sample was calculated to be 15 nm. The band gap of the synthesized GO is found to be 5.1 eV and that of ZnO to be 3.07 eV with the help Tauc plot. The dependence of various concentration of ZnO on the electrical behaviour is discussed by an impedance analyzer in the frequency range 100Hz to 1MHz. The ZnO/GO composite with best results have been obtained for 20% and 60 % ratios of ZnO. The composite has high dielectric permittivity and low loss tangent values and is identified as a promising candidate for energy storage applications. 2019 The Authors. -
Parametric investigation on the tool wear while performing face milling on inconel 718 using round insert
Machining of Inconel 718 has become a material of great purpose in the machining industry. Since Inconel is considered to be a super alloy which possess high material property such as high thermal fatigue, high strength and high resistance to corrosion it is thus considered to be a material which is hard to machine. This paper gives an overview on the tool wear that takes place while machining. Machining was carried out in a CNC milling machine with the help of a tungsten carbide circular insert. The cutting parameters taken into consideration were cutting speed, feed rate and depth of cut. Tool wear was analysed with the help of tool makers microscope. Statistical analysis was done on the MINITAB 18 software by using regression analysis. The regression analysis was carried out by using Response Surface Methodology (RSM) the mathematical model for each individual response has been developed from regression equations considering analysis of cutting parameters as independent variables which was found to be significantly accurate. BEIESP. -
Experimenting with resilience and scalability of wifi mininet on small to large SDN networks
Today everything is getting digitized where people want to be wireless by all aspects. There is a high demand of WiFi in every sector. Highest influence on network planning of newly developed network infrastructure is of SDN to meet the futuristic needs of upcoming technology. As a result, newly developed networks have become more adaptive to dynamic circumstances along with enhanced flexibility. Being globally connected, it is inevitable to obtain adequate services from data centers through Wi-Fi support on SDN Networks, which is still a dream. Thus, the target of the experiment performed and presented by the authors of this paper is to implement WiFi support on SDN. Further, authors have also demonstrated the scalability and resilience of SDN based WiFi Network on Mininet by testing performance parameters in various dynamic scenarios. This paper will have a high impact on the end users as SDN technology can be implemented as last mile technology using WiFi SDN. BEIESP. -
A Note on the Rainbow Neighbourhood Number of Certain Graph Classes
A rainbow neighbourhood of a graph G is the closed neighbourhood N[v] of a vertex v? V(G) which contains at least one colored vertex of each color in the chromatic coloring C of G. Let G be a graph with a chromatic coloring C defined on it. The number of vertices in G yielding rainbow neighbourhoods is called the rainbow neighbourhood number of the graph G, denoted by r ? (G). In this paper, rainbow neighbourhood number of certain graph classes are discussed. 2018, The National Academy of Sciences, India. -
Investigation of speech synthesis, speech processing techniques and challenges for enhancements
The sound produced by any human being or instrument can be used for various applications using the concept of extraction or selection. Using this concept, virtual sounds are produced which is prime requirement for various speech synthesis applications. In this paper we review the different speech processing methodologies, parameters involved and the various applications based on the speech quality produced. Though an overview is given on the processing and involved parameter, priority is given to the speech enhancement application. This survey helps to identify the challenges involved in various processing technique involved in speech enhancement of healthy and disordered speech. These findings with different speech production and speech synthesis techniques will help to improve the quality in various application of speech to text (STT), text to speech (TTS), Automatic speech production (ASP) and Automatic speech recognition (ASR). Copyright 2019 American Scientific Publishers All rights reserved. -
Some New Results on the Rainbow Neighbourhood Number of Graphs
A rainbow neighbourhood of a graph G is the closed neighbourhood N[v] of a vertex v? V(G) which contains at least one coloured vertex of each colour in the chromatic colouring C of G. Let G be a graph with a chromatic colouring C defined on it. The number of vertices in G yielding rainbow neighbourhoods is called the rainbow neighbourhood number of the graph G, denoted by r?(G). Rainbow neighbourhood number of the complements and products of certain fundamental graph classes are discussed in this paper. 2018, The National Academy of Sciences, India. -
Effect of heat treated HNT on physico-mechanical properties of epoxy nanocomposites
Halloysite Nano Tubes (HNTs) are naturally occurring Kaolite group minerals having an aluminosilicate-layer in the form of nanotubes which are known to enhance the properties of the polymer matrix composites when effectively dispersed in the epoxy matrix phase. In this regard, the present work is carried out to fabricate the composite specimens by polymer stir casting techniques and evaluate the basic properties viz., density, hardness, tensile strength, flexural strength, impact strength and the microstructure using Transmission electron microscopy (TEM) for better morphological studies of the dispersions in the nanocomposites with a filler content of 0, 5 and 10 wt% of HNT's that are effectively treated at three temperature conditions viz., Room temperature (RT), 50 C and 70 C according to specified ASTM test methods selected after thorough investigations and review of literature. As per the experimental investigation, the mechanical properties of the nanocomposite increases by the incorporation of heat treated HNT. Further, the study revealed that the nano composite with a filler content of 10 Wt.% of HNT preheat treated at 50 C shows superior tensile and flexural strength, However the critical observation of the results reveal that the impact strength is maximum for Nano composites with a filler content of 5 Wt.% HNT pre heat treated at 70 C. The study of TEM images gives an overview of uniform dispersion of HNTs in the matrix phase owing to varying pre-treatment conditions. It is evident that the properties of the nanocomposite depends on the quantity of functional filler present and temperature of heat treatment. 2019 Elsevier Ltd -
Biodegradation studies of polyhydroxyalkanoates extracted from Bacillus subtilis NCDC 0671
The major characteristic feature that distinguishes polyhydroxyalkanoates (PHAs) from its synthetic counterparts is its biodegradability. PHAs are the only class of biopolymers reported to be 100% degradable under both aerobic and anaerobic conditions without production of any toxic residues. The biodegradability of PHAs is influenced by several factors like moisture, temperature, pH, surface area and molecular weight of the polymer. The rate of biodegradation varies greatly depending on the environment. Biodegradation studies were carried out using plating method and direct inoculation method using selected Bacillus strains. Fungal degradation of PHA sheets was assessed using Penicillium chrysogenum. Biodegradation of PHA sheets in different soil types like river valley, agricultural land and garden soil was investigated. The degree of PHA degradation in aqueous environment was studied by incubating the sheets in distilled water, sea water, fish tank water and pond water. The highest degradation rate was observed with agriculture land soil (35.47 0.13%) and fish tank soil (36.93 0.13%). The non-toxic nature of the soil incubated with PHA sheets was ensured using plant growth test. 2019, World Research Association. All rights reserved. -
A stochastic propagation model to the energy dependent rapid temporal behaviour of Cygnus X-1 as observed by AstroSat in the hard state
We report the results from analysis of six observations of Cygnus X-1 by Large Area X-ray Proportional Counter (LAXPC) and Soft X-ray Telescope (SXT) onboard AstroSat, when the source was in the hard spectral state as revealed by the broad-band spectra. The spectra obtained from all the observations can be described by a single-temperature Comptonizing region with disc and reflection components. The event mode data from LAXPC provides unprecedented energy dependent fractional root mean square (rms) and time-lag at different frequencies which we fit with empirical functions.We invoke a fluctuation propagation model for a simple geometry of a truncated disc with a hot inner region. Unlike other propagation models, the hard X-ray emission (>4 keV) is assumed to be from the hot inner disc by a single-temperature thermal Comptonization process. The fluctuations first cause a variation in the temperature of the truncated disc and then the temperature of the inner disc after a frequency dependent time delay.We find that the model can explain the energy dependent rms and time-lag at different frequencies. 2019 The Author(s) Published by Oxford University Press on behalf of the Royal Astronomical Society. -
Analysis of machining parameters for face milling of inconel 718 using response surface methodology
The machining of Inconel 718 which is a nickel based super alloy has become a material of great importance mainly in the aerospace industry. Reason being the materials possesses properties of increase in strength at elevated temperature, high resilience to chemical reaction and high wear resistance. Gaining optimum machining parameters have become a great concern in the manufacturing industry, where economy of machining plays a very important key role in the market. This paper gives an overview of the experimentation conducted on the basis of Response Surface Methodology (RSM). Regression equations have been developed for surface roughness, by taking into consideration the machining parameters like cutting speed, feed rate and depth of cut for face milling operation performed in CNC machine. RSM analysis was carried out with the help of Mini Tab 18 software. The Mathematical equation developed after regression analysis shows to be very efficient. BEIESP. -
Managing change, growth and transformation: Case studies of organizations in an emerging economy
Purpose: In view of dynamic and widespread economic transformation in emerging economies, managing organizational change and growth in this context deserves more research attention. The purpose of this paper is to examine how three organizations in different industries manage change, growth and transformation in their organizational ecosystem. Design/methodology/approach: The authors conducted in-depth interviews with the leadership of three organizations in different economic sectors in India, a country representing an emerging economy. The authors also reviewed historical data from these organizations. Three case studies illustrating the evolution of these organizations were developed from the data collected. Findings: Lessons and implications from the three case studies suggest the following key elements of effective organizational change mechanisms in an emerging economy: visionary entrepreneurial leadership; program quality excellence; scale growth and scope expansion; network capabilities; and sustainable stakeholders engagement. At the same time, this study also shows how these organizations manage change, growth and transformation in the context of a society with strong traditions and cultural norms. Research limitations/implications: Results and conclusions may be limited by the fact that the study is based on three case studies. Additional studies from a variety of industries with large numbers of participants will be helpful in more fully understanding the ways in which change, growth and transformation can best be developed and deployed in different organizational settings. Practical implications: The proposed model of organizational change in an emerging economy may assist organizational leadership in designing and sustaining their change efforts. Social implications: This study highlights the role of visionary entrepreneurial leadership and the impact of organizational growth mechanisms on organizational value delivery capabilities and organizational reputation. Originality/value: Lessons and implications of five growth steps of outstanding organizations in an emerging economy context provide valuable insight for organizational change, growth and transformation in other emerging contexts. 2019, Emerald Publishing Limited.