Deep Learning Research: Scientometric Assessment of Global Publications Output during 2004 -17

The paper provides a quantitative and qualitative description of deep learning research using bibliometric indicators covering global research publications published during 14-year period 2004-17. Global deep learning research registered 106.76% high growth per annum, and averaged 7.99 citations per paper. Top 10 countries world- over dominate the research field with their 99.74% global publications share and more than 100% global citations share. China ranks the top with the highest (29.25%) global publications share, followed by USA (26.46%), U.K. (6.40%), etc. during the period. Canada tops in relative citation index (5.30). International collaboration has been a major driver of research in the subject with 14.96% to 53.76% of national-level share of top 10 countries output appeared as international collaborative publications. Computer Science is one of the most popular areas of research in deep learning research (76.85% share). The study identifies top 50 most productive organizations and 50 most productive authors and top 20 most productive journals reporting deep learning research and 118 highly cited papers with 100+ citations per paper

Multi-messenger constraints on the Hubble constant through combination of gravitational waves, gamma-ray bursts and kilonovae from neutron star mergers

The simultaneous detection of gravitational waves and light from the binary neutron star merger GW170817 led to independent measurements of distance and redshift, providing a direct estimate of the Hubble constant $H_0$ that does not rely on a cosmic distance ladder nor assumes a specific cosmological model. By using gravitational waves as ''standard sirens'', this approach holds promise to arbitrate the existing tension between the $H_0$ value inferred from the cosmic microwave background and those obtained from local measurements. However, the known degeneracy in the gravitational-wave analysis between distance and inclination of the source lead to a $H_0$ value from GW170817 that was not precise enough to resolve the existing tension. In this review, we summarize recent works exploiting the viewing-angle dependence of the electromagnetic signal, namely the associated short gamma-ray burst and kilonova, to constrain the system inclination and improve on $H_0$. We outline the key ingredients of the different methods, summarize the results obtained in the aftermath of GW170817 and discuss the possible systematics introduced by each of these methods

Mobile computing: a scientometric assessment of global publications output

The paper examines 34641 global publications output on mobile computing research, as covered in Scopus database during 2007-16. The study finds that mobile computing research is growing at 9.35% rate per annum and its citation impact averaged to 3.39 citations per paper. The global share of top 10 most productive countries ranged from 3.29% to 31.06%, with largest global publication share coming from China (31.06%), followed by USA (15.35%), etc. Together, the top 10 most productive countries accounted for 81.24% global publication share during 2007-16. Seven of top 10 countries achieved relative citation index above world average of 1: USA (2.37), U.K. (1.78), Italy (1.72), Canada (1.64), etc. International collaborative publications share of top 10 most productive countries in mobile computing research during 2007-16 varied from 11.55% to 48.16%. Computer Science, among subjects, accounted for the largest publication share (89.55%), followed by engineering (33.58%), social sciences (18.67%), mathematics (8.74%), etc. during 2007-16. The top 20 most productive organizations and authors contributed 14.79% and 1.76% global publication share respectively and accounted for 9.5% and 5.11% global citation share respectively during 2007-16. The top 20 journals accounted for 24.11% share of total journals output of 5673 papers during 2007-16. The top 50 highly cited publications registered citations in the range from 164 to 1235 citations per paper and together these top 50 papers cumulated 16822 citations, with an average of 336.4 citations per paper. These 50 highly cited papers resulted from participation of 184 authors and 103 organizations, and were published in 31 journals, including 4 in IEEE Transactions on Mobile Computing, 2 papers each in Decision Support System, IEEE Communication Magazine, IEEE Pervasive Computing and IEEE Communication Surveys & Tutorials and 1 paper each in other 26 journals.

iPTF16abc and the population of Type Ia supernovae: Comparing the photospheric, transitional and nebular phases

Key information about the progenitor system and the explosion mechanism of Type Ia supernovae (SNe~Ia) can be obtained from early observations, within a few days from explosion. iPTF16abc was discovered as a young SN~Ia with excellent early time data. Here, we present photometry and spectroscopy of the SN in the nebular phase. A comparison of the early time data with a sample of SNe~Ia shows distinct features, differing from normal SNe~Ia at early phases but similar to normal SNe~Ia at a few weeks after maximum light (i.e. the transitional phase) and well into the nebular phase. The transparency timescales ($t_0$) for this sample of SNe~Ia range between $\sim$ 25 and 41 days indicating a diversity in the ejecta masses. $t_0$ also weakly correlates with the peak bolometric luminosity, consistent with the interpretation that SNe with higher ejecta masses would produce more $^{56}$Ni. Comparing the $t_0$ and the maximum luminosity, L$_{max}$\, distribution of a sample of SNe~Ia to predictions from a wide range of explosion models we find an indication that the sub-Chandrasekhar mass models span the range of observed values. However, the bright end of the distribution can be better explained by Chandrasekhar mass delayed detonation models, hinting at multiple progenitor channels to explain the observed bolometric properties of SNe~Ia. iPTF16abc appears to be consistent with the predictions from the M$_{ch}$ models.Comment: 13 pages, 8 figures, accepted for publication in MNRA

Nebular spectroscopy of SN 2014J: Detection of stable nickel in near infrared spectra

We present near infrared (NIR) spectroscopy of the nearby supernova 2014J obtained $\sim$450 d after explosion. We detect the [Ni II] 1.939 $\mu$m line in the spectra indicating the presence of stable $^{58}$Ni in the ejecta. The stable nickel is not centrally concentrated but rather distributed as the iron. The spectra are dominated by forbidden [Fe II] and [Co II] lines. We use lines, in the NIR spectra, arising from the same upper energy levels to place constraints on the extinction from host galaxy dust. We find that that our data are in agreement with the high $A_V$ and low $R_V$ found in earlier studies from data near maximum light. Using a $^{56}$Ni mass prior from near maximum light $\gamma$-ray observations, we find $\sim$0.05 M$_\odot$ of stable nickel to be present in the ejecta. We find that the iron group features are redshifted from the host galaxy rest frame by $\sim$600 km s$^{-1}$.Comment: 6 pages, 4 figures, submitted to A&

High Radiation Resistant DC-DC Converter Regulators for use in Magnetic fields for LHC High Luminosity Silicon Trackers

For more efficient power transport to the electronics embedded inside large colliding beam detectors, we explore the feasibility of supplying higher DC voltage and using local DC-DC conversion to 1.3 V (or lower, depending upon on the lithography of the embedded electronics) using switch mode regulators located very close to the front end electronics. These devices will be exposed to high radiation and high magnetic fields, 10 – 100 Mrads and 2 - 4 Tesla at the SLHC

On the characteristics of the plankton at Kandla in the Gulf of Kutch during August 1958—July 1960

The study of plankton and hydrology is of fundamental importance in the marine biological research programmes and our present knowledge on these aspects, which still remains far from satisfactory, is owing to a few contributions (Bal et al 1946, Bal and Pradhan 1952 ; Chidambaram and Menon 1945 ; Ganapati and Sarma 1958; George 1953; Jacob and Menon 1947 ; Hornell and Nayudu 1923 ; Menon 1945 ; Prasad 1956 ; Ramamurthy 1953 and Subrahmanyan 1959). Practically no information is available from the Gulf of Kutch on the west coast of India

Multi-wavelength INTEGRAL NEtwork (MINE) observations of the microquasar GRS 1915+105

We present the international collaboration MINE (Multi-lambda Integral NEtwork) aimed at conducting multi-wavelength observations of X-ray binaries and microquasars simultaneously with the INTEGRAL gamma-ray satellite. We will focus on the 2003 March-April campaign of observations of the peculiar microquasar GRS 1915+105 gathering radio, IR and X-ray data. The source was observed 3 times in the plateau state, before and after a major radio and X-ray flare. It showed strong steady optically thick radio emission corresponding to powerful compact jets resolved in the radio images, bright near-infrared emission, a strong QPO at 2.5 Hz in the X-rays and a power law dominated spectrum without cutoff in the 3-300 keV range. We compare the different observations, their multi-wavelength light curves, including JEM-X, ISGRI and SPI, and the parameters deduced from fitting the spectra obtained with these instruments on board INTEGRAL.Comment: 4 pages, 9 fig., Proc. of the 5th INTEGRAL Workshop (Feb. 16-20 2004), to be published by ES