2,831 research outputs found
Hybrid static/dynamic scheduling for already optimized dense matrix factorization
We present the use of a hybrid static/dynamic scheduling strategy of the task
dependency graph for direct methods used in dense numerical linear algebra.
This strategy provides a balance of data locality, load balance, and low
dequeue overhead. We show that the usage of this scheduling in communication
avoiding dense factorization leads to significant performance gains. On a 48
core AMD Opteron NUMA machine, our experiments show that we can achieve up to
64% improvement over a version of CALU that uses fully dynamic scheduling, and
up to 30% improvement over the version of CALU that uses fully static
scheduling. On a 16-core Intel Xeon machine, our hybrid static/dynamic
scheduling approach is up to 8% faster than the version of CALU that uses a
fully static scheduling or fully dynamic scheduling. Our algorithm leads to
speedups over the corresponding routines for computing LU factorization in well
known libraries. On the 48 core AMD NUMA machine, our best implementation is up
to 110% faster than MKL, while on the 16 core Intel Xeon machine, it is up to
82% faster than MKL. Our approach also shows significant speedups compared with
PLASMA on both of these systems
The Role of Earthworms in Tropics with Emphasis on Indian Ecosystems
The paper highlights the research carried out by different scientists in India on aspects of earthworm population dynamics and species diversity, associated with other soil fauna and microflora. It also deals with the importance of earthworm activity on physicochemical properties of soil with reference to India and other tropical countries. Stress is laid on the earthworm plant association and importance of the secretions of earthworms as plant growth stimulators. Moreover, the earthworm species reported and being utilized for vermicomposting in India are discussed, since vermicomposting is the ultimate technology which renders for the improvement of soil fertility status and plant growth. Earthworms serve as indicators of soil status such as the level of contamination of pollutants: agrochemicals, heavy metals, toxic substances, and industrial effluents; human-induced activities: land-management practices and forest degradation. In all these fields there is lacuna with respect to contributions from India when compared to the available information from other tropical countries. There is lot of scope in the field of research on earthworms to unravel the importance of these major soil macrofauna from holistic ecological studies to the molecular level
On the occurrence of Radio Halos in galaxy clusters - Insight from a mass-selected sample
Giant radio halos (RH) are diffuse Mpc-scale synchrotron sources detected in
a fraction of massive and merging galaxy clusters. An unbiased study of the
statistical properties of RHs is crucial to constrain their origin and
evolution. We aim at investigating the occurrence of RHs and its dependence on
the cluster mass in a SZ-selected sample of galaxy clusters, which is as close
as possible to be a mass-selected sample. Moreover, we analyse the connection
between RHs and merging clusters. We select from the Planck SZ catalogue
(Planck Collaboration XXIX 2014) clusters with
at z=0.08-0.33 and we search for the presence of RHs using the NVSS for z<0.2
and the GMRT RH survey (GRHS, Venturi et al. 2007, 2008) and its extension
(EGRHS, Kale et al. 2013, 2015) for 0.2<z<0.33. We use archival Chandra X-ray
data to derive information on the clusters dynamical status. We confirm that RH
clusters are merging systems while the majority of clusters without RH are
relaxed, thus supporting the idea that mergers play a fundamental role in the
generation of RHs. We find evidence for an increase of the fraction of clusters
with RHs with the cluster mass and this is in line with expectations derived on
the basis of the turbulence re-acceleration scenario. Finally, we discuss the
effect of the incompleteness of our sample on this result.Comment: 11 pages, 7 figures, accepted for publication in A&
To evaluate the clinical efficacy of Palash Mula Arka in Pittaja Netrabhishyanda
Abhishyanda is one of the Sarvagata Vyadhi mentioned by Acharya Sushruta. In modern science, signs and symptoms of Netrabhishyanda may be correlated with conjunctivitis, which is the inflammatory condition of conjunctiva. Kavala Dharana, Dhumrapana, Aschyotana, Sechana Putapaka etc. are various suggested regimens in Ayurvedic texts for the treatment of Netrabhishyanda. Considering this effectiveness of Palasha as mentioned by Acharya Sushruta, it is planned to study the use of Palasha Mula Arka Aschyotana in Pittaja Netrabhishyanda. 60 patients having classical signs and symptoms of Pittaja Abhishyanda (Acute Bacterial Conjunctivitis) as per Ayurvedic and modern texts were selected for the study. After completion of therapy, mean Conjunctival hyperemia was reduced to 0.2167 ± 0.4086 in Control and 0.5667 ± 0.5040 in Trial Group. Palasha Mula Arka was found effective in reduction in conjunctival hyperemia, watering and the number of culture colonies, it was also found effective in burning sensation, discharge, foreign body sensation and photophobia
The Extended GMRT Radio Halo Survey I: New upper limits on radio halos and mini-halos
A fraction of galaxy clusters host diffuse radio sources called radio halos,
radio relics and mini-halos. We present the sample and first results from the
Extended GMRT Radio Halo Survey (EGRHS)- an extension of the GMRT Radio Halo
Survey (GRHS, Venturi et al. 2007, 2008). It is a systematic radio survey of
galaxy clusters selected from the REFLEX and eBCS X-ray catalogs . Analysis of
GMRT data at 610/ 235/ 325 MHz on 12 galaxy clusters are presented. We report
the detection of a newly discovered mini-halo in the cluster RXJ1532.9+3021 at
610 MHz. A small scale relic (~200 kpc) is suspected in the cluster Z348. We do
not detect cluster-scale diffuse emission in 11 clusters. Robust upper limits
on the detection of radio halo of size of 1 Mpc are determined. We also present
upper limits on the detections of mini-halos in a sub-sample of cool-core
clusters. The upper limits for radio halos and mini-halos are plotted in the
radio power- X-ray luminosity plane and the correlations are discussed. Diffuse
extended emission, not related to the target clusters, but detected as
by-products in the sensitive images of two of the cluster fields (A689 and
RXJ0439.0+0715) are reported. Based on the information about the presence of
radio halos (or upper limits), available on 48 clusters out of the total sample
of 67 clusters (EGRHS+GRHS), we find that ~23% of the clusters host radio
halos. The radio halo fraction rises to ~31%, when only the clusters with X-ray
luminosities >8x10^44 erg/s are considered. Mini-halos are found in ~50 % of
cool-core clusters. A qualitative examination of the X-ray images of the
clusters with no diffuse radio emission indicates that a majority of these
clusters do not show extreme dynamical disturbances and supports the idea that
mergers play an important role in the generation of radio halos/relics.Comment: 21 pages, 18 figures, 3 tables, accepted for publication in A&
Malware security for Android Components using Layer permission
Today’s open source android smartphone operating system is adept of executing the multifaceted and enormous application, which increases the installation of diverse applications with increase in chance of installation of malware application. The behavior pattern of android is depicted by the requested permission of application. System explores a way to detect malware application based on requested permission by the application. Detection of malware application is done in two steps; first step is to selecting representative features by applying the FAST algorithm. Whereas representative feature is extracted permissions, requested in the application. In second step classification of application is done as a malware or benign application using support vector machine (SVM). Using FAST and SVM algorithms system can discriminate android application as malware also enrich the performance of malware detection system.
DOI: 10.17762/ijritcc2321-8169.15053
Effect of nanoclay loading on zeta potential of polyester nanocomposite fibre
Polyester (PET) nanocomposite fibres have been melt spun by adding master batches of linear low density polyethylene (LLDPE) loaded with organophilic nanoclay after compatibilizing the PET and LLDPE. The spun fibres show increased hydrophobicity which further increases progressively with the amount of nanoclay loaded into the fibre. The addition of this nanoclay also results in improved dyeability of the nanocomposite fibres with acid dyes due to the presence of quaternary ammonium organic substituent that is present in the nanoclay. There is slight decrease in tensile strength of the fibre accompanied by the decrease in elongation %, indicating that the addition of nanoclay makes the filaments stiffer. The onset of crystallization temperature occurs at higher temperature in case of composite fibres than in case of neat PET fibre because of nucleating effect of nanoclay
Rotational viscoelastic laminar boundary layer flow around a rotating disc
The equations of motion for the laminar boundary layer flow over a rotating disc have been derived for a fluid which obeys a Rivlin-Ericksen type of constitutive equation and whose material parameters are assumed to be arbitrary functions of the second invariant of the rate of deformation tensor. The analysis establishes the conditions under which a true similarity solution is possible. An inspectional analysis yields a relationship between the moment coefficient, a generalized Reynolds number and a modified Weissenberg number which incorporates a variable relaxation time with a process time characteristic of the boundary layer flow on the disc. Experimental data obtained are analysed in terms of the derived relationship and the agreement between the two, after the determination of the unknown constants, is found to be quite sound. A brief discussion follows which emphasizes the role of geometry, regime of flow and viscoelastic material parameters in giving a wide variety of flow phenomena
New giant radio sources and underluminous radio halos in two galaxy clusters
The aim of this work is to analyse the radio properties of the massive and
dynamical disturbed clusters Abell 1451 and Zwcl 0634.1+4750, especially
focusing on the possible presence of diffuse emission. We present new GMRT 320
MHz and JVLA 1.5 GHz observations of these two clusters. We found that both
Abell 1451 and Zwcl 0634.1+4750 host a radio halo with a typical spectrum
(). Similarly to a few other cases reported in the recent
literature, these radio halos are significantly fainter in radio luminosity
with respect to the current radio power-mass correlations and they are smaller
than classical giant radio halos. These underluminous sources might contribute
to shed light on the complex mechanisms of formation and evolution of radio
halos. Furthermore, we detected a candidate radio relic at large distance from
the cluster center in Abell 1451 and a peculiar head tail radio galaxy in Zwcl
0634.1+4750, which might be interacting with a shock front.Comment: 15 pages, 13 figures, accepted for publication in A&
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