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Undetectable least significant bit replacement steganography
No full textIn this paper we propose a novel method based on Inverse Transitions for increasing the security of Least Significant Bit (LSB) replacement steganography. Before hiding data using LSB replacement, cover image is preprocessed using inverse transitions. The preprocessing modifies the LSBs in such a way that the resulting change in pixel values can not occur with LSB replacement. The proposed method ensures 100% undetectability for payload up to 1.5 bpp in colour images against most accurate length estimation methods for LSB replacement. The proposed method is faster, does not require any additional storage and ensures complete recovery of hidden data in comparison to state of the art steganography methods. The proposed method can be used in resource constrained applications which demand fast and secure data hiding and loss less recovery of hidden data
Search for the pair production of light top squarks in the e(+/-)mu(-/+) final state in proton-proton collisions at root s=13 TeV
No full textA search for the production of a pair of top squarks at the LHC is presented. This search targets a region of parameter space where the kinematics of top squark pair production and top quark pair production are very similar, because of the mass difference between the top squark and the neutralino being close to the top quark mass. The search is performed with 35.9 fb(-1) of proton-proton collisions at a centre-of-mass energy of root s = 13 TeV, collected by the CMS detector in 2016, using events containing one electron-muon pair with opposite charge. The search is based on a precise estimate of the top quark pair background, and the use of the M-T2 variable, which combines the transverse mass of each lepton and the missing transverse momentum. No excess of events is found over the standard model predictions. Exclusion limits are placed at 95% confidence level on the production of top squarks up to masses of 208 GeV for models with a mass difference between the top squark and the lightest neutralino close to that of the top quark
Positive Threshold Voltage Shift in AlGaN/GaN HEMTs and E-Mode Operation By AlxTi1-xO Based Gate Stack Engineering
No full textIn this paper, for the first time, we have experimentally demonstrated enhancement mode (e-mode) AlGaN/GaN high-electron-mobility transistor (HEMT) operation by integrating p-type high-kappa AlxTi1-xO based gate stack. Concentrationof Al in Al-Ti-O system was found to be a tuning parameter for the threshold voltage of GaN HEMTs. The high-kappa properties of AlxTi1-xO as a function of Al % are studied. Superiority of AlTiO over other p-oxides such as CuO and NiOx is proven statistically. Using the high-kappa and p-type AlTiO, in conjunction with a thinner AlGaN barrier under gate, 600-V e-mode GaN HEMTs are demonstrated with superior ON-state performance (I-ON similar to 400 mA/mm and R-ON = 8.9 Omega-mm) and gate control over channel (I-ON/I-OFF = 10(7), SS=73mV/dec, and gate leakage < 200nA/mm), beside improved safe operating area reliability
MIMO-OTFS in High-Doppler Fading Channels: Signal Detection and Channel Estimation
No full textOrthogonal time frequency space (OTFS) modulation is a recently introduced multiplexing technique designed in the 2-dimensional (2D) delay-Doppler domain suited for high-Doppler fading channels. OTFS converts a doubly-dispersive channel into an almost non-fading channel in the delay-Doppler domain through a series of 2D transformations. In this paper, we focus on MIMO-OTFS which brings in the high spectral and energy efficiency benefits of MIMO and the robustness of OTFS in high-Doppler fading channels. The OTFS channel-symbol coupling and the sparse delay-Doppler channel impulse response enable efficient MIMO channel estimation in high Doppler environments. We present an iterative algorithm for signal detection based on message passing and a channel estimation scheme in the delay-Doppler domain suited for MIMO-OTFS. The proposed channel estimation scheme uses impulses in the delay-Doppler domain as pilots for estimation. We also compare the performance of MIMO-OTFS with that of MIMO-OFDM under high Doppler scenarios
Low-cost and nontoxic highly rectifying diodes using p-type tin monosulfide (SnS) thin films and Ti/Au binary contacts
No full textEco-friendly and efficient rectifying p-n diodes have been developed by using cost-effective and non-toxic fin monosulfide (SnS) thin films. Chemically stoichiometric fin monosulfide (SnS) thin films followed by titanium/gold (Ti/Au) bilayer contacts were deposited on Si substrates and then, the structures were treated by rapid thermal annealing process (RTP) at different temperatures. The impact of RTP treatment on the surface morphology and chemical composition of Ti/Au contacts and SnS films along with their electrical characteristics were investigated. The electrical measurements show that as compared to untreated Si/SnS/Ti/Au structures, the heat-treated structures typically at 200 degrees C possess low electrical resistivity and contact resistance of similar to 3 x 10(-2) Omega cm and similar to 11 k Omega, respectively. Heterojunction formed between p-SnS and n-Si exhibited excellent diode characteristics and possess a high current flow in the order of milliamperes, and excellent rectification factor of 1177@ 5 V
Enhanced tensile properties of novel bio-waste synthesized carbon particle reinforced composites
No full textLow cost, catalyst free porous carbon nanospheres (CNSs) of size 60-70 nm, synthesized from bio-waste products, were used as fillers to fabricate a novel polymer matrix nanocomposite (PMNC) with two different filler contents, viz. 0.1 and 0.25 wt% in an epoxy resin. The composites were tested for their tensile strength and elastic modulus. The 0.25 wt%. composite showed similar to 30% improvement in tensile strength, similar to 7% increase in elastic modulus and similar to 50% increase in % elongation with respect to that of the base resin properties. This study offers exciting structural applications for CNS materials. (C) 2019 Elsevier B.V. All rights reserved
Cascaded Plasma-Ozone Injection System: A Novel Approach for Controlling Total Hydrocarbon Emission in Diesel Exhaust
No full textThe hydrocarbons present in diesel exhaust, although treated as minor pollutants, are equivalent to some of the major pollutants in terms of toxicity, contamination and harmfulness to the environment and hence, any effort towards treating hydrocarbons is a welcome step before letting the same into the atmosphere. In this current work two non-thermal plasma techniques viz., electrical discharge plasma (direct plasma) and ozone injection (indirect plasma) were coupled while treating the diesel exhaust for possible mitigation of total hydrocarbons (THC). The work is intended to provide a cleaning system which is non-catalytic, non-adsorbent and non-thermal plasma based one leading to less utilization of electrical energy and long lasting. The study was conducted at laboratory level with controlled flow conditions of the diesel exhaust. It was observed that the combined discharge plasma and ozone injection has resulted in more of THC reduction/conversion to the tune of 95% at about plasma specific energy of 55J/L and with an injection of 1656ppm of ozone. The individual as well as cascaded treatment techniques are discussed in detail and a comparative analysis of the same has been provided
Self-assembly of a ``cationic-cage'' via the formation of Ag-carbene bonds followed by imine condensation
No full textA new strategy for the synthesis of a ``cationic-cage'' (CC-Ag) has been developed via metal-carbene (M-CNHC) bond formation followed by imine bond condensation. Reaction of a trigonal trisimidazolium salt H3L(PF6)(3) functionalized with three flexible N-phenyl-aldehyde pendants with silver oxide yielded a trinuclear tricationic organometallic cage (OC-Ag). Subsequent treatment of the organometallic cage (OC-Ag) with 1,4-diaminobutane links the two tris-NHC ligands via imine bond condensation, which thus generates a 3D `cationiccage' (CC-Ag). Furthermore, post-synthetic replacement of the Ag(I) with Au(I) leading to the formation of CC-Au was achieved via trans-metalation, with the retention of the molecular architecture
ESD Behavior of AlGaN/GaN Schottky Diodes
No full textThis experimental study reports behavior of Ni/Au-based AlGaN/GaN Schottky diodes under ESD conditions. A comparative study of diodes with/without recessed Schottky contact unfolds different degradation physics in each case. The impact of different current conduction mechanisms, device degradation and trap generation on its robustness are analyzed. The role of interface traps under ESD failure of the GaN Schottky diode is investigated. The transition from soft-to-hard failure, which is found to depend on the presence of traps, and diode design is discussed. New insights into degradation trends, cumulative nature of degradation, and trap-assisted failure modes are discovered
Phase diagram of the system Ce-Rh-O
No full textAlthough important for catalytic applications, a phase diagram for the ternary system Ce-Rh-O is not found in the literature. Phase diagrams of most Ln-Rh-O systems show LnRhO(3) with orthorhombic perovskite structure as the lone stable ternary oxide. Based on systematic trends in experimentally determined thermodynamic properties of eleven LnRhO(3) compounds, the Gibbs energy of formation of CeRhO3 is evaluated as a function of temperature. For the reaction, 1/2 Ce2O3 (A-rare earth) + 1/2 Rh2O3 (ortho) -> CeRhO3, Delta G degrees/J mol(-1) = -69,336 + 5.26(T / K). The estimated data for CeRhO3 along with evaluated data for the binary Ce-Rh and data for binary oxides from the literature are used to compute the phase diagram for the system Ce-Rh-O at high temperature. Because of the significantly higher stability of CeO2-x compared to Ce2O3, the compound CeRhO3 is found to be unstable. A section of the phase diagram and an oxygen potential - composition diagram for the system Ce-Rh-O at 1200 K are computed from thermodynamic data