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Medical image fusion technology and its collective diagnosis are becoming crucial day by day. This task confers the latest algorithm for image fusion of medical images to many diagnostic complications. Firstly, transform is employed on input source images. The result of the application of transform is the decomposition of source images into various subbands. Eminent features are extracted from these subbands by using resnet50. These features are fused by phase congruency and guided filtering fusion rules. Finally, inverse transform gives the original image. The experiment results of this algorithm are compared with different methods by taking some pairs of medical images. Subjective and objective outcomes prove that the proposed algorithm exceeds the current methods by giving optimal performance measures in the area of medical diagnosis. Thus, it is revealed that the suggested multimodal image fusion model provides elevated performance over existing models via diverse diseases using MRI-SPECT and MRI-PET. [ABSTRACT FROM AUTHOR]

We have developed a micro-controller based Deep Level Transient Spectroscopy (DLTS) system to identify the deep-level defects in semiconductors. It consists of Arduino-Due, a capacitance meter, and interface circuits. In addition, we have also developed the algorithms needed for the entire signal processing. It is not limited to Arduino-Due but can be implemented using other micro-controllers also. We have used Arduino-Due to generate the filling pulse and monitor the capacitance, temperature, data acquisition, timing control, and signal processing. The sequence of generating the filling pulse, reading the data, and signal processing is controlled digitally rather than by analog sampling circuits and timers. The minimum pulse width generated using Arduino-Due is 50 ns; the pulse width generation depends on various hardware and software parameters and their integration. The resolution in reading the data is 0.8 mV/unit. The time delays in reading the data are appropriately taken care of in the system. The whole experiment can be completed in a single temperature cycle within 2–3 h. The system is simple, inexpensive, in an easy-to-use platform, and less time-consuming; minimizes possible errors; and improves accuracy. The measurements using the "micro-controller based DLTS system" are verified by fabricating (Au) gold-doped silicon (Si) p–n junction samples (Au is a well-understood defect in Si). Using the Arduino-Due based DLTS system, we calculated the energy, the capture cross section, and the concentration of trap levels. The results are in good agreement with the literature, indicating the versatility of the system. [ABSTRACT FROM AUTHOR]

Hafnium oxide (HfO2) has been explored as high-κ gate dielectrics in scaled CMOS devices, artificial synapses to be used in neuromorphic computing to achieve brain-like functionalities, a storage layer in memory devices, a piezoelectric energy harvester, and a photodetector. In this article, the origin of a native defect present in the HfO2 thin films on silicon is experimentally probed using deep level transient spectroscopy (DLTS) technique. It was realized that defects (predominantly oxygen vacancies) in HfO2 segregate near the Si/HfO2 interface. The interfacial and bulk HfO2 trap charges are communicating through the tunneling/ hopping, and, finally, they are emitted to the respective bands of silicon depending on the silicon used. We have observed four prominent defect states, and we believe that all these belong to oxygen vacancies in different charge states. The activation energies of trap states are in the range of 1.22–2.02 eV from the HfO2 conduction band edge, and they fall in front of the Si bandgap in the band alignment of the Al/HfO2/Si gate stack. The capture cross sections of these traps are measured with insufficient filling DLTS and found to be of the order of 10−19 cm2. The results provide valuable insights into realizing the behavior of oxygen vacancy-related deep defects in HfO2 and guide their possible impact on the device performance. [ABSTRACT FROM AUTHOR]

The synthesis and the structural and luminescence studies of samarium-doped calcium aluminate phosphors are reported. These phosphors are synthesized by the solid-state reaction method with a variable concentration of doping ions (0.5–3.0 mol%). The synthesized phosphors are characterized by the X-ray diffraction (XRD), scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FTIR) techniques. The XRD studies show that the doped phosphors have a cubic structure. The SEM images reveal that the Sm3+- doped Ca3Al2O6 phosphor represents a combination of some rod-like and flower-like structures. The FTIR studies confirm the formation of a Ca3Al2O6:Sm3+ phosphor. The photoluminescence (PL) emission measurements upon excitation by 273 nm (ultraviolet light) show the characteristic emission peaks of Sm3+ at 579, 589, 600 and 619 nm. The characteristic orange-red emission is observed for samarium ion. The excitation spectra of the Ca3Al2O6:Sm3+ phosphor mainly consist of a more intense charge transfer band (CTB) of Sm3+ located at 273 and 395 nm with some peaks centred at 319 and 362 nm. The CIE coordinates are calculated by the spectrophotometric method using the spectral energy distribution of the Ca3Al2O6:Sm3+ sample. The prepared phosphors can act as a single host for orange-red light emission in display devices. [ABSTRACT FROM AUTHOR]

The Indus Basin is one of the most vulnerable regions due to climate change. This article presents the mean precipitation and temperature changes along with their extremes over the Indus Basin (IB). Here we used the statistically downscaled, bias-corrected, high-resolution data from the newly emerged Coupled Model Intercomparison Project Phase 6 (CMIP6) of two Shared Socioeconomic Pathways (SSP2-4.5 and SSP5-8.5) in response to global warming. The spatial variations of precipitation, maximum and minimum temperature obtained from the Multi-Model Mean (MMM) of CMIP6 models showed a good agreement with APHRODITE (precipitation) and CPC (temperature) for the base period (1995–2014) over the basin. Results suggest that the precipitation may increase as high as 40% from June to September (JJAS) and 25% from December to February (DJF) in the SSP5-8.5 scenario by the end of the century. Future temperature projections show that warming may continue over the basin. A significant warming was noticed in the SSP5-8.5 scenario than the SSP2-4.5 scenario, with a maximum increase of more than 4 °C towards the end of the twenty-first century. Analysis of spatiotemporal variations of future extreme precipitation indices viz RD, SDII, RX1DAY, RX5DAY, R10MM, R20MM except CDD are high in number over Upper Indus Basin (UIB) compared to Lower Indus Basin (LIB). Extreme temperature indices such as TXx, SU, CSU, TNn, FD, CFD, TR except for ID show an increase of 40% to more than 75% under the SSP5-8.5 scenario compared to the baseline period over the basin. [ABSTRACT FROM AUTHOR]

In the present study, we analyse large-scale connections to deadly heatwaves in India in spring. Deadly Indian heatwaves occur in the spring months of April and May, and are increasing in recent years. These events are associated with the amplification of planetary Rossby waves. This amplification is called quasi-resonant amplification (QRA). An increase of amplitude or resonance occurs when stationary and moving waves coincide in their size. Previous studies stressed QRA’s role in summer because persistent extreme weather events such as the 2003 European heatwave, the 2010 Pakistan flood, Russian heatwave, the 2011 Texas and Oklahoma heat waves, and drought occurred in summer. QRA seems to be related to the amplification of Arctic warming in winter and summer, but observations show that Arctic warming occurs in spring also. The novel aspect of our study is that we found strong evidence for QRA in the boreal spring, the season of Indian heatwaves. Amplified Arctic warming or Arctic amplification thought to be responsible for QRA occurs in spring also. Our results confirm that maximum surface temperatures in spring over India show predictability with high statistical significance, about 4 days ahead. Maximum surface temperatures can be used to predict heatwaves, as shown earlier by some authors. [ABSTRACT FROM AUTHOR]

Presents information on a study which analyzed the interaction of gold-related defects with irradiation-induced defects in silicon. Preparation of neutron-transmutation-doped silicon; Measurement of current-voltage parameters of silicon; Conclusions.

Deals with a study which determined the simulated emission cross section for the transition of neodymium in lead borate and bismuth borate glasses through fluorescence measurements. Theoretical framework; Experimental details; Results and discussion; Conclusions.

Investigates the effect of hydrogenation and thermal annealing on the photoluminescence of p-indium phosphide. Observation on thermally-induced donor-acceptor transition in the samples; Photoluminescence spectra of magnesium-doped indium phosphide; Experimental details and result of the study.

Focuses on the relation between gold related levels in silicon with deep level transient spectroscopy using linearly graded junctions. Calculation of the defect concentrations; Background doping of the thyristor sample; Measurement of the majority-carrier capture cross sections.

Provides information on a study which observed improvements in the optical and electrical properties of gallium antimonide after ruthenium passivation. Effect of ruthenium passivation on gallium antimonide; Observation on the passivation and luminescence efficiency of ruthenium; Discussion of the boundary passivation of polycrystallines.

The nature of the signal due to light beam induced current (LBIC) at the remote contacts is verified as a lateral photovoltage for non-uniformly illuminated planar p-n junction devices; simulation and experimental results are presented. The limitations imposed by the ohmic contacts are successfully overcome by the introduction of capacitively coupled remote contacts, which yield similar results without any significant loss in the estimated material and device parameters. It is observed that the LBIC measurements introduce artefacts such as shift in peak position with increasing laser power. Simulation of LBIC signal as a function of characteristic length Lc of photo-generated carriers and for different beam diameters has resulted in the observed peak shifts, thus attributed to the finite size of the beam. Further, the idea of capacitively coupled contacts has been extended to contactless measurements using pressure contacts with an oxidized aluminium electrodes. This technique avoids the contagious sample processing steps, which may introduce unintentional defects and contaminants into the material and devices under observation. Thus, we present here, the remote contact LBIC as a practically non-destructive tool in the evaluation of device parameters and welcome its use during fabrication steps. [ABSTRACT FROM AUTHOR]

Abstract: Mechanical properties of poly(3-hexylthiophene) (P3HT)/[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) blend films, prepared under different processing conditions, were evaluated by nanoindentation. Photovoltaic devices fabricated using above active layers presented the highest power conversion efficiencies for blend films having lowest Young’s modulus (20.73GPa) and hardness (649MPa), as measured by a nanoidentator under optimized conditions of blend proportion (1:1), film drying rate (slow) and annealing temperature and time (110°C and 10min). It implies that the degree of nano-scale phase separation for the P3HT:PCBM blend is strongly correlated with the mechanical properties in the nanodimension. The nanoindentation is a method to estimate nano-scale mechanical properties of blend films and the performance of photovoltaic cells. [Copyright &y& Elsevier]

Nasicons (sodium super ion conductors) are a class of solid electrolytes. Their structure, compositional diversity, evolution, and applications are reviewed. A wide range of materials is considered based on crystalline and glassy Nasicon compositions. [ABSTRACT FROM AUTHOR]

Nasicon type compounds of general formula Ca0.5SbMP3O12 (M = Al, Fe, Cr) are prepared by solid-state method. All the compounds crystallize in hexagonal lattice with $$ R \,\bar 3\,c $$ space group. The IR spectra show characteristic PO4 vibrations. Conductivity studies indicate the presence of charged defects. The Cole-Cole plots of impedance are semicircles between 150 and 350 °C. The thermal expansion of these samples is studied in the temperature range 25–500 °C. [ABSTRACT FROM AUTHOR]

Abstract: In the process of preparing a visible light photocatalyst CaIn2O4, a novel core shell like composite In2O3@CaIn2O4 was observed at intermediate calcination temperatures, during the solid-state reaction between ball milled powders of CaCO3 and In2O3. The composition, crystallinity and photo absorption of the coupled phases obtained in the temperature range 873–1323K, were characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM) and UV–vis diffused reflectance spectroscopy. The coupled composite phases In2O3@CaIn2O4 showed superior visible light induced photocatalytic degradation of Methylene Blue (MB) compared to single phase CaIn2O4. Selective charge separation and efficient charge transport at the interface when illuminated are considered to be the possible reasons for the enhanced photocatalytic performance of this composite catalyst. [Copyright &y& Elsevier]

Abstract: Bulk and nano sized pyrochlore of composition La2−x Gd x Zr2O7 (x =0.025, 0.05, 0.075 and 0.1) have been prepared by sol–gel method. They are characterized by powder X-ray diffraction and infrared spectroscopy. The sintering temperature influences the particle size of the sample. The room temperature powder ESR of La1.95Gd0.05Zr2O7 gave characteristic “U” spectrum. The influence of particle size on the ESR of Gd3+ is investigated. Possible reason for the disappearance of “U” spectrum with increase in the particle size is given. [Copyright &y& Elsevier]

Abstract: Preparation, characterization and electrical properties of new silver nasicons of composition AgTaMP3O12 (M=Al, Ga, In, Cr, Fe and Y) have been investigated. All compositions crystallize in the rhombohedral nasicon structure and are found to be isomorphous with NbTiP3O12. The space group of all compositions is R3¯c except AgTaYP3O12, which crystallizes in R3¯ space group. All the compounds show characteristic PO4 vibrational bands. DC conductivity studies (by two-probe method) and AC impedance measurements correlate well. The Cole–Cole plots do not show any spikes on the lower frequency side indicating negligible electrode effects. The isothermal conductivity obtained from DC (σ dc) and AC (σ(0)) agrees well. The activation energies obtained from the plots of log σ dc versus 1/ T, log σ(0) versus 1/ T and log τ versus 1/ T are approximately the same suggesting conducting species to be mobile silver ions. The peak width at half height for Mʺ modulus plot is ∼1.34 decades for all samples, which is close to 1.14 decades observed for Debye solid. The height of Mʺ obtained from the experimental plots are close to that of Mʺ (max)= C 0 /2C indicating the Debye nature of the samples. The room temperature Mössbauer spectrum of AgTaFeP3O12 suggests paramagnetic nature of this sample. [Copyright &y& Elsevier]

Abstract: A new copper Nasicon of composition Cu0.5TaFeP3O12 has been prepared and reduced under hydrogen flow at 500 and 675°C, separately. The unreduced and reduced products are characterized by IR spectra and powder X-ray diffraction. The copper Nasicon and the products obtained by its reduction crystallize in the rhombohedral lattice with space group . The ESR and Mössbauer spectral results suggest only partial reduction of both Cu2+ and Fe3+ to Cu+ and Fe2+, respectively, with simultaneous hydrogen insertion to balance the charge. A reaction in conformity with the obtained results is proposed. [Copyright &y& Elsevier]

The compound CaTiFeP3O12 has been converted to HxCaTiFe1−x3+Fex2+P3O12 by reduction using hydrogen. The reduced product is characterized by powder X-ray diffraction (XRD) and Mo¨ssbauer spectroscopy and its unit cell parameters are deduced. Mo¨ssbauer spectral results suggest that CaTiFeP3O12 could not be reduced completely. The effect of heat treatment on the reduced product has been studied. [Copyright &y& Elsevier]

The rare-earth borates of composition LnB3O6 (Ln=Sm, Eu and Gd) have been prepared and their infrared and magnetic susceptibility were studied. The infrared spectra show the characteristic bands due to planar BO3 and tetrahedral BO4 units. The DC susceptibilities were measured from 5 to 300 K. The electron paramagnetic resonance (EPR) spectrum for Gd3+ was recorded at room temperature. The EuB3O6 and SmB3O6 show van Vleck paramagnetism, corresponding to the ground state 7F0 of Eu3+ and 6H5/2 of Sm3+, respectively. From the susceptibility data of EuB3O6 and SmB3O6, spin–orbit coupling constants of 348 and 458 cm−1 were obtained for Eu3+ and Sm3+, respectively. The magnetic susceptibility of GdB3O6 follows the Curie law. From the EPR measurement the g value of Gd3+ in GdB3O6 is found to be 2.01. Both the EPR measurements and magnetic susceptibility results agree well and show that Gd3+ ion in this compound is scarcely affected by the crystal field. [Copyright &y& Elsevier]

HgTe nanocrystals (NCs) have unique properties that make them suitable for optoelectronic devices in the mid-wave infrared (MWIR) and short-wave infrared regions. However, electrically active defects can trap charge carriers, reducing their mobility and diffusion length, which degrades the NCs' optical and electrical properties. In this study, we used the thermal admittance spectroscopic (TAS) method to analyze defects in HgTe NC-based photovoltaic devices. The ITO/HgTe/Al device structure was used to study the defect levels in HgTe nanocrystals and the effect of these traps on transport properties. Using low-temperature I–V measurements, we calculated the trap activation energy as 0.14 eV, and the transport was found to occur mainly through these trap states. From the TAS measurements, the trap activation energy obtained was 0.14 eV, and the concentration of trap level was 3.16 × 10 16 cm − 3 eV − 1 . We have also fabricated ITO/ TiO 2 /HgTe/Au and fluorine doped tin oxide/ TiO 2 /HgTe/ MoO 3 /Au devices and did TAS measurements to understand the effect of adding electron and hole extraction layer on the formation of defect levels. Intriguingly, a distinct reversal in the capacitance–frequency (C–F) behavior is observed at different temperatures, leading to positive slopes in the Arrhenius plot. This peculiar phenomenon is attributed to the size-dependent doping effects within the HgTe nanocrystals. The outcomes of this study shed light on the significance of understanding and quantifying electrically active defects in HgTe nanocrystals for the advancement of NC-based optoelectronic devices. [ABSTRACT FROM AUTHOR]

Summertime heat stress future projections from multi-model mean of 18 CMIP5 models show unprecedented increasing levels in the RCP 4.5 and RCP 8.5 emission scenarios over India. The estimated heat stress is found to have more impact on the coastal areas of India having exposure to more frequent days of extreme caution to danger category along with the increased probability of occurrence. The explicit amount of change in temperature, increase in the duration and intensity of warm days along with the modulation in large scale circulation in future are seemingly connected to the increasing levels of heat stress over India. A decline of 30 to 40% in the work performance is projected over India by the end of the century due to the elevated heat stress levels which pose great challenges to the country policy makers to design the safety mechanisms and to protect people working under continuous extreme hot weather conditions. [ABSTRACT FROM AUTHOR]

The carrier density dependent current-voltage (J-V) characteristics of electrochemically prepared poly(3-methylthiophene) (P3MeT) have been investigated in Pt/P3MeT/Al devices, as a function of temperature from 280 to 84 K. In these devices, the charge transport is found to be mainly governed by different transport regimes of space charge limited conduction (SCLC). In a lightly doped device, SCLC controlled by exponentially distributed traps (Vl+1 law, l>1) is observed in the intermediate voltage range (0.5-2 V) at all temperatures. However, at higher bias (>2 V), the current deviates from the usual Vl+1 law where the slope is found to be less than 2 of the logJ-logV plot, which is attributed to the presence of the injection barrier. These deviations gradually disappear at higher doping level due to reduction in the injection barrier. Numerical simulations of the Vl+1 law by introducing the injection barrier show good agreement with experimental data. The results show that carrier density can tune the charge transport mechanism in Pt/P3MeT/Al devices to understand the non-Ohmic behavior. The plausible reasons for the origin of injection barrier and the transitions in the transport mechanism with carrier density are discussed. [ABSTRACT FROM AUTHOR]

ABSTRACT: We have used 1° × 1° resolution maximum temperature (TMAX) data sets developed by India Meteorological Department (IMD) to examine the summer time warming over India during the period 2001–2014 in comparison with the period 1971–2000. The two study periods have been arrived at based on the drastic change of Moisture Index (IM) trends over India between the two epochs. The TMAX variations over India are discussed with the corresponding changes in Potential Evapotranspiration (PET) data of the Climate Research Unit (CRU) and Outgoing Longwave Radiation (OLR) data of NOAA ESRL. The study shows a considerable warming over northern parts of India compared to southern parts. Western Himalayas (WH) and Northwest (NW) regions experienced highest warming with 1.4 °C and 0.8 °C increases during Epoch 2 (2001–2014) as compared Epoch 1 (1971–2000) during the summer (March, April and May). Using MERRA Black Carbon Surface Mass Concentration (BCSMC) data, we have analysed the relation of increasing BCSMC with the TMAX over different homogeneous temperature regions of India and found that BCSMC has increased upto 1.6 times between the two epochs. Strong linear association is found between TMAX, PET and OLR evidenced by Coherence Wavelet Spectral analysis. It is also found that the highest warming occurred in the month of March and is 2.2 °C in WH and 1.4 °C in NW parts of India. We calculated mass stream function based on zonal mean meridional velocity for the two periods. In the recent periods we observed the weakening of polar cell and northward expansion of Hadley cell. These changes may be related to warming conditions of the atmosphere which may explain the intensification and northward expansion of the Ferrel cell with favourable conditions during the summer season. [ABSTRACT FROM AUTHOR]

The authors of the present paper studied some aspects of hydro and agrometeorological phenomena in terms of humidness, dryness and crop growing periods over India. Revised water balance model is used to obtain the above and the results are examined during the two half centuries i.e 1901 to 1950 and 1951 to 1995 in delineating the climate change impacts over India. Palmer Drought Severity Index (PDSI) for All India is related to aridity and humidity indices to understand the dry and wet spells over India. The paper also holds its stand on the analysis and the trends of thermo and hygric components such as precipitation, maximum and minimum temperatures, water need, actual evapotranspiration and soil moisture for All India. The return rates of All India maximum and minimum rainfall and temperatures are obtained for different time intervals using Extreme Value Analysis, that might be useful in assessing the impact and thereby to plan over the risk management for the better environmental and thus the human sustainability. [ABSTRACT FROM AUTHOR]

Abstract: New Nasicon type of compounds of composition AgSbMP3O12 (M=Al, Ga, Fe and Cr) are synthesized by solid-state method. All the compounds crystallize in the hexagonal lattice with space group . The infrared spectra of these compounds show characteristic bands due to PO4 group. The frequency independent conductivity of these compounds shows Arrhenius type behavior and the activation energy for conduction is in the range 0.40–0.55eV. Frequency independent conductivity (σ dc) studies and frequency dependent (σ ac) impedance measurements correlate well. The Cole–Cole plots do not show any spikes on the lower frequency side indicating negligible electrode effects. The activation energies obtained from the plots of log σ dc T versus 1/T, log σ ac(0) versus 1/T and log τ versus 1/T are approximately the same. The peak width at half height for electric modulus (M″) plot is ∼1.24 decades for all samples, which is close to 1.14 decades observed for Debye solid. The height of electric modulus (M″) obtained from the experimental plots are close to that of M″ (max)= C 0/2C indicating the Debye nature of the samples. [Copyright &y& Elsevier]

Hydrothermally grown mercury cadmium telluride quantum dots (CdHgTe QDs) are decorated on graphene oxide (GO) sheets through physisorption. The structural change of GO through partial reduction of oxygen functional groups is observed with X-ray photoelectron spectroscopy in GO-QDs composites. Raman spectroscopy provides relatively a small change (~1.1 times) in D/G ratio of band intensity and red shift in G band from 1606 cm-1 to 1594 cm-1 in GO-CdHgTe QDs (2.6 nm) composites, which indicates structural modification of GO network. Steady state and time resolved photoluminescence (PL) spectroscopy shows the electronic interactions between photoexcited near infrared emitting CdHgTe QDs and GO. Another interesting observation is PL quenching in the presence of GO, and it is quite effective in the case of smaller size QDs (2.6 nm) compared to the larger size QDs (4.2 nm). Thus, the observed PL quenching is attributed to the photogenerated electron transfer from QDs to GO. The photoexcited electron transfer rate decreases from 2.2 × 109 to 1.5 × 108 s-1 with increasing particle size from 2.6 to 4.2 nm. Photoconductivity measurements on QDs-GO composite devices show nearly 3 fold increase in the current density under photo-illumination, which is a promising aspect for solar energy conversion and other optoelectronic applications. [ABSTRACT FROM AUTHOR]

Temperature and photo-dependent current–voltage characteristics are investigated in thin film devices of a hybrid-composite comprising of organic semiconductor poly(3,4-ethylenedioxythiophene): polystyrenesulfonate (PEDOT:PSS) and cadmium telluride quantum dots (CdTe QDs). A detailed study of the charge injection mechanism in ITO/PEDOT:PSS-CdTe QDs/Al device exhibits a transition from direct tunneling to Fowler–Nordheim tunneling with increasing electric field due to formation of high barrier at the QD interface. In addition, the hybrid-composite exhibits a huge photoluminescence quenching compared to aboriginal CdTe QDs and high increment in photoconductivity (~ 400%), which is attributed to the charge transfer phenomena. The effective barrier height (ΦB ≈ 0.68 eV) is estimated from the transition voltage and the possible origin of its variation with temperature and photo-illumination is discussed. [ABSTRACT FROM AUTHOR]

The present study explored the performance of the current coupled models obtained from the Asia Pacific Economic Cooperation (APEC) Climate Centre (APCC) in representing the tropical Indo-Pacific sea surface temperature (SST) and rainfall during boreal summer season (June through September; JJAS). We have used the retrospective/hindcast runs for 28 years from 1983 to 2010 initialized in May. The mean SST bias in the tropical Indo-Pacific Oceans showed large diversity among the models in JJAS. In the case of the rainfall, most of the models displayed a strong dry bias over the major continental regions and wet biases over the tropical oceans. The majority of the models simulated the Inter-annual variability (IAV) of JJAS rainfall and SST reasonably well over the equatorial Pacific region, where the models are close to observed IAV and maximum signal to noise ratio (SNR). It is found that the models display, low IAV of rainfall and SST over the Indian Ocean with low SNR values, resulting in less predictive skill as compared to the tropical Pacific region. Similarly, all models showed a higher skill in summer rainfall prediction over the oceanic regions compared to the Asian land region, where SNR is very low. Further analysis suggested that the models have greater skill in predicting El Niño-Southern Oscillation (ENSO). The category wise analysis showed that models could predict 60–70% of the extreme ENSO events, but the normal events are represented only by 50%. It is noted that the models predict many false alarms for El Niño resulting in a higher frequency of El Niño occurrence. This is mainly responsible for stronger ENSO and the Asian Monsoon teleconnections in the models than in the observations. Meanwhile, the category wise rainfall skill for extended Indian monsoon region (EMR) displayed 50–60% accuracy for the extreme monsoon years and is around 50% for normal years. However, models such as CCSM3, CFSV2, and CANCM3 have displayed higher rainfall skills over EMR as compared to the other models possibly due to better representation of teleconnections spatial patterns between EMR rainfall and SST anomalies over Indo-Pacific Oceans. [ABSTRACT FROM AUTHOR]

In the present study, rainfall estimates from TRMM (Tropical Rainfall Measuring Mission) and GPM (Global Precipitation Mission) constellation of satellites are analyzed in the context of rainfall induced landslide occurrences over Western Ghats (WG) of India along with the daily gridded rainfall data developed by the India Meteorological Department (IMD) and Advanced Research Weather Research and Forecasting (ARW) numerical model simulations. This study aims to analyze the pattern of changes in rain rate and total rainfall triggering the large landslides over WG in TMPA (product of TRMM) and IMERG (GPM product) rainfall data sets. As a case study, performance of IMERG V5 is assessed during Malin landslide which occurred on 30 July 2014 (initial GPM era). Results indicate that IMERG shows significant increase in rain rate (>60 mm/h in half-hourly data) during Malin landslide. Near real-time IMERG V5, underestimates the rain rate but increasing pattern of rain-rate are observed which is similar to that of final version. Spatial pattern of ARW rainfall output is also close to the satellite and IMD rainfall patterns. We propose that IMERG V5 can be used as an indicator to reliably depict the higher rainfall scenario over the sites that are vulnerable to rainfall induced landslide occurrence over the WG region. [ABSTRACT FROM AUTHOR]

Present study focuses on rainfall over Western Ghats (WG), a complex topographic region (elevation > 500 m) of India to evaluate and to better understand the satellite behavior in contrast with a flat region (FR) (elevation < 500 m) of central India from 1998 to 2016 using the combinatory data sets of TMPA and IMERG (satellite rainfall estimation). The categorical Intra Seasonal Oscillations (ISO) of Indian summer monsoon (ISM) namely, Madden Julian Oscillation (MJO) and Quasi Bi-Weekly Oscillation (QBWO) are tested in satellite and India Meteorological Department (IMD) gridded rainfall data sets to find out the satellite performance. As the accurate estimation of rainfall from satellites over higher elevation zones is challenging, here we propose a new perspective to select the rainfall products of satellite for better comparison with ground measurements. Considering the satellite's best capability in detecting the cold clouds resulting from deep convection and its coupling with higher-level circulation, we show that the rainfall from satellites yield fruitful comparison with ground measurements when moist static stability, tropical easterly jet is above the climatological values. [ABSTRACT FROM AUTHOR]

Quantum ensembles form easily accessible architectures for studying various phenomena in quantum physics, quantum information science and spectroscopy. Here we review some recent protocols for measurements in quantum ensembles by utilizing ancillary systems. We also illustrate these protocols experimentally via nuclear magnetic resonance techniques. In particular, we shall review noninvasive measurements, extracting expectation values of various operators, characterizations of quantum states and quantum processes, and finally quantum noise engineering. [ABSTRACT FROM AUTHOR]

The electrical conductivity of cobalt and titanium substituted barium hexagonal ferrites of different compositions has been investigated as a function of composition and temperature. Plots of log(σT) versus 103/T are almost linear and show a transition near the Curie temperature. The activation energy in the ferrimagnetic region is in general less than that in the paramagnetic region. An attempt is made to explain the conduction mechanism in Ba–Co–Ti ferrites. [Copyright &y& Elsevier]

We report the nonlinear optical absorption studies in two differently sized water-soluble cadmium telluride quantum dot (QD) samples, exhibiting first excitonic absorption peaks at 493 nm and 551 nm, respectively. An optical limiting behavior is observed for near-resonant excitation at 532 nm using nanosecond laser pulses, originating from the effective two-photon absorption (TPA) mechanism. The effective TPA coefficient (βeff) is measured to be in the range of 10-12 m/W. This is one order of magnitude higher than the TPA coefficient (β) reported for off-resonant excitation. At this excitation wavelength, the smaller QD shows a relatively weaker photoluminescence and stronger nonlinear absorption. [ABSTRACT FROM AUTHOR]