464 research outputs found
In-Vehicle Data Communication with CAN &Security Monitoring: A Review
Automobiles are now being created with more electronic components for efficient functioning such as Anti Lock Braking system, Adaptive Cruise Control, Traction control system, Airbag, Power Steering etc. managed by networked controllers that include hundreds of ECUs (electronic control units) that can coordinate, control, and monitor loads of internal vehicle components. Each component, such as ABS, TCS (Traction control system), tire pressure monitoring system and telematics system, may communicate with nearby components over the CAN (Controller Area Network) bus, establishing an in-vehicle communication network. These modern automobile system networks intended for safety with minimal consideration for security have drawn the attention of researchers for providing security in CAN. The Paper reviews the behavior and vulnerabilities of CAN within an in-vehicle network including various attacks possible in CAN along with the proposed solutions in the literature with extensive survey on a security promising approach named as IDS (Intrusion detection system)
Lesser Known Ethnomedicinal Plants of Alagar Hills, Madurai District of Tamil Nadu, India
The ethnobotanical uses of plant species viz. Embelia basal (Roxb.) DC., Gymnema lactiferum R.Br., Ophiorrhiza mungos L., and Syzygium alternifolium (Wight) Walp. were recorded from Alagar hills of Madurai district, Tamil Nadu
Structural and Electrical Studies of NixSn1-xO2 Sn Dopped Nickel Oxide Thin Film by Jet Nebulizer Spray Pyrolysis Technique for Photodiode and Solar Cell Applications
The dissertation deals with preparation and characterization of NixSn1-xO2 thin films by the jet nebulizer spray pyrolysis technique at optimized temperature 450°C with Ni dopants. The films were analysed to understand the structural, surface morphology, optical and electrical studies for NixSn1-xO2 thin. Moreover, in the case of transparent oxide films, the thickness increases linearly with time of spray. Also, the growth of thin films is temperature dependent. At low temperatures, the growth rate is controlled by activated processes, such as adsorption, surface diffusion chemical reaction and desorption. However, at high temperatures, the activated processes occur so fast and the molecules do not dam up on the substrate. Growth rate also depends on the size of the droplets, because the decomposition of droplet is temperature dependent. If the droplet size is large, the heat absorbed from the surroundings will not be sufficient to vaporize entirely the solvent on the way to the substrate and adversely affect the kinetics of the reaction. The XRD Pattern of NixSn1-xO2 shows the polycrystalline nature with orthorhombic structure and is oriented through (021) direction. The grain size of the prepared films is increased up to x=0.2 and then decreased slightly, for x= 0.8 the grain increases. The conductivity of NixSn1-xO2(x=0) at room temperature is 2.8×10-4s/cm and the other compositions (x=0.2, 0.4, 0.8) show the decrease of conductivity to 2.4×10-6s/cm. The maximum transmittance ( 75%) shows in IR region and 70%of transmittance in the visible region at x=0.4. The band gap value of NixSn1-xO2 films is 2.96, 2.98 and 3.0 ev for x=0.8 0.2 and 0.4 respectively. It can be used for diode and solar cell applications due to the higher transmittance and decreases of band gap energy
Resolving the decades-long transient FIRST J141918.9+394036: an orphan long gamma-ray burst or a young magnetar nebula?
Ofek (2017) identified FIRST J141918.9+394036 (hereafter FIRST J1419+3940) as
a radio source sharing similar properties and host galaxy type to the compact,
persistent radio source associated with the first known repeating fast radio
burst, FRB 121102. Law et al. (2018) showed that FIRST J1419+3940 is a
transient source decaying in brightness over the last few decades. One possible
interpretation is that FIRST J1419+3940 is a nearby analogue to FRB 121102 and
that the radio emission represents a young magnetar nebula (as several
scenarios assume for FRB 121102). Another interpretation is that FIRST
J1419+3940 is the afterglow of an `orphan' long gamma-ray burst (GRB). The
environment is similar to where most such events are produced. To distinguish
between these hypotheses, we conducted radio observations using the European
VLBI Network at 1.6 GHz to spatially resolve the emission and to search for
millisecond-duration radio bursts. We detect FIRST J1419+3940 as a compact
radio source with a flux density of (on 2018
September 18) and a source size of (i.e. given the angular diameter distance of ).
These results confirm that the radio emission is non-thermal and imply an
average expansion velocity of . Contemporaneous
high-time-resolution observations using the 100-m Effelsberg telescope detected
no millisecond-duration bursts of astrophysical origin. The source properties
and lack of short-duration bursts are consistent with a GRB jet expansion,
whereas they disfavor a magnetar birth nebula.Comment: 8 pages, 4 figures, accepted for publication in ApJ
Effect of medium, explants, cytokinins and node position on in vitro shoot multiplication of Caralluma lasiantha (Wight) N.E.Br., an endemic and medicinally important plant
An efficient shoot multiplication protocol was developed for Caralluma lasiantha, an endemic medicinal plant belonging to the family Asclepiadaceae. Mature explants were cultured on Murashige and Skoog (MS), (1962) medium, Gamborg's B5 (B5) and woody plant medium (WPM) supplemented with 6-benzyladenine (BA), 8.87 µM, for shoot induction. The nodal explants exhibited maximum shoot sprouting frequency when cultured on MS medium supplemented with BA (8.87 µM). Nodal explants cultured on MS medium supplemented with different concentrations of cytokinins with 3% sucrose exhibited 100% sprouting frequency. Maximum number of three to four shoots was induced from mature second nodal explants on MS medium containing BA (8.87 µM). The isolated microshoots were rooted on half strength MS medium supplemented with naphthalene acetic acid (NAA), 0.54 µM. The plantlets thus developed were hardened and successfully established in soil.Key words: 6-Benzyl adenine, nodal explant, naphthalene acetic acid, Caralluma lasiantha, micro propagation
Observing Pulsars with a Phased Array Feed at the Parkes Telescope
During February 2016, CSIRO Astronomy and Space Science and the
Max-Planck-Institute for Radio Astronomy installed, commissioned and carried
out science observations with a phased array feed (PAF) receiver system on the
64m diameter Parkes radio telescope. Here we demonstrate that the PAF can be
used for pulsar observations and we highlight some unique capabilities. We
demonstrate that the pulse profiles obtained using the PAF can be calibrated
and that multiple pulsars can be simultaneously observed. Significantly, we
find that an intrinsic polarisation leakage of -31dB can be achieved with a PAF
beam offset from the centre of the field of view. We discuss the possibilities
for using a PAF for future pulsar observations and for searching for fast radio
bursts with the Parkes and Effelsberg telescopes.Comment: 10 pages, 8 figures, 2 tables. It has been accepted for publication
in PAS
SYMBA: An end-to-end VLBI synthetic data generation pipeline:Simulating Event Horizon Telescope observations of M 87
In vitro shoot multiplication and conservation of Caralluma bhupenderiana Sarkaria - an endangered medicinal plant from South India
An efficient protocol was described for the rapid in vitro multiplication of an endangered medicinal plant, Caralluma bhupenderiana Sarkaria, via enhanced axillary bud proliferation from nodal explants collected from young shoots of six-months-old plant. The physiological effects of growth regulators [6- Benzyladenine (BA), kinetin (Kn), 2-Isopentyl adenine (2iP), zeatin (Zn), indole-3-acetic acid (IAA), indole-3-butyric acid (IBA)], different strengths of Murashige and Skoog (MS) medium and various pH levels on in vitro morphogenesis were investigated. The highest number (8.40 + 0.50) of shoots and the maximum average shoot length (3.2 ± 0.31 cm) were recorded on MS medium supplemented with BA (8.87 μM) at pH 5.8. Rooting was best achieved on half-strength MS medium augmented with NAA (2.69 μM). The plantlets regenerated in vitro with well-developed shoot and roots were successfully established in pots containing peat mass and garden manure in 1:1 ratio and grown in a greenhouse with 80% survival rate. The regenerated plants did not show any immediate detectable phenotypic variation.Key words: Apocynaceae, asclepiadoideae, conservation, micro-propagation, endangered, Caralluma bhupenderiana
The beamformer and correlator for the Large European Array for Pulsars
The Large European Array for Pulsars combines Europe's largest radio
telescopes to form a tied-array telescope that provides high signal-to-noise
observations of millisecond pulsars (MSPs) with the objective to increase the
sensitivity of detecting low-frequency gravitational waves. As part of this
endeavor we have developed a software correlator and beamformer which enables
the formation of a tied-array beam from the raw voltages from each of
telescopes. We explain the concepts and techniques involved in the process of
adding the raw voltages coherently. We further present the software processing
pipeline that is specifically designed to deal with data from widely spaced,
inhomogeneous radio telescopes and describe the steps involved in preparing,
correlating and creating the tied-array beam. This includes polarization
calibration, bandpass correction, frequency dependent phase correction,
interference mitigation and pulsar gating. A link is provided where the
software can be obtained.Comment: 10 pages, 6 figures, accepted for publication in Astronomy and
Computin
Resolving the decades-long transient FIRST J141918.9+394036: an orphan long gamma-ray burst or a young magnetar nebula?
Ofek (2017) identified FIRST J141918.9+394036 (hereafter FIRST J1419+3940) as
a radio source sharing similar properties and host galaxy type to the compact,
persistent radio source associated with the first known repeating fast radio
burst, FRB 121102. Law et al. (2018) showed that FIRST J1419+3940 is a
transient source decaying in brightness over the last few decades. One possible
interpretation is that FIRST J1419+3940 is a nearby analogue to FRB 121102 and
that the radio emission represents a young magnetar nebula (as several
scenarios assume for FRB 121102). Another interpretation is that FIRST
J1419+3940 is the afterglow of an `orphan' long gamma-ray burst (GRB). The
environment is similar to where most such events are produced. To distinguish
between these hypotheses, we conducted radio observations using the European
VLBI Network at 1.6 GHz to spatially resolve the emission and to search for
millisecond-duration radio bursts. We detect FIRST J1419+3940 as a compact
radio source with a flux density of (on 2018
September 18) and a source size of (i.e. given the angular diameter distance of ).
These results confirm that the radio emission is non-thermal and imply an
average expansion velocity of . Contemporaneous
high-time-resolution observations using the 100-m Effelsberg telescope detected
no millisecond-duration bursts of astrophysical origin. The source properties
and lack of short-duration bursts are consistent with a GRB jet expansion,
whereas they disfavor a magnetar birth nebula.Comment: 8 pages, 4 figures, accepted for publication in ApJ
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