Indian Institute of Technology Bhubaneswar

About: Indian Institute of Technology Bhubaneswar is a education organization based out in Bhubaneswar, India. It is known for research contribution in the topics: Large Hadron Collider & Higgs boson. The organization has 1185 authors who have published 3132 publications receiving 48832 citations.

Influence of convective parameterization on the systematic errors of Climate Forecast System (CFS) model over the Indian monsoon region from an extended range forecast perspective

Abstract: This study investigates the influence of Simplified Arakawa Schubert (SAS) and Relax Arakawa Schubert (RAS) cumulus parameterization schemes on coupled Climate Forecast System version.1 (CFS-1, T62L64) retrospective forecasts over Indian monsoon region from an extended range forecast perspective. The forecast data sets comprise 45 days of model integrations based on 31 different initial conditions at pentad intervals starting from 1 May to 28 September for the years 2001 to 2007. It is found that mean climatological features of Indian summer monsoon months (JJAS) are reasonably simulated by both the versions (i.e. SAS and RAS) of the model; however strong cross equatorial flow and excess stratiform rainfall are noted in RAS compared to SAS. Both the versions of the model overestimated apparent heat source and moisture sink compared to NCEP/NCAR reanalysis. The prognosis evaluation of daily forecast climatology reveals robust systematic warming (moistening) in RAS and cooling (drying) biases in SAS particularly at the middle and upper troposphere of the model respectively. Using error energy/variance and root mean square error methodology it is also established that major contribution to the model total error is coming from the systematic component of the model error. It is also found that the forecast error growth of temperature in RAS is less than that of SAS; however, the scenario is reversed for moisture errors, although the difference of moisture errors between these two forecasts is not very large compared to that of temperature errors. Broadly, it is found that both the versions of the model are underestimating (overestimating) the rainfall area and amount over the Indian land region (and neighborhood oceanic region). The rainfall forecast results at pentad interval exhibited that, SAS and RAS have good prediction skills over the Indian monsoon core zone and Arabian Sea. There is less excess rainfall particularly over oceanic region in RAS up to 30 days of forecast duration compared to SAS. It is also evident that systematic errors in the coverage area of excess rainfall over the eastern foothills of the Himalayas remains unchanged irrespective of cumulus parameterization and initial conditions. It is revealed that due to stronger moisture transport in RAS there is a robust amplification of moist static energy facilitating intense convective instability within the model and boosting the moisture supply from surface to the upper levels through convergence. Concurrently, moisture detrainment from cloud to environment at multiple levels from the spectrum of clouds in the RAS, leads to a large accumulation of moisture in the middle and upper troposphere of the model. This abundant moisture leads to large scale condensational heating through a simple cloud microphysics scheme. This intense upper level heating contributes to the warm bias and considerably increases in stratiform rainfall in RAS compared to SAS. In a nutshell, concerted and sustained support of moisture supply from the bottom as well as from the top in RAS is the crucial factor for having a warm temperature bias in RAS.

Effect of plasma treatment on multilayer graphene: X-ray photoelectron spectroscopy , surface morphology investigations and work function measurements

Abstract: We report here the effect of plasma treatment on multilayer graphene samples as determined by X-ray photoelectron spectroscopy and surface morphology studies with atomic force microscopy, scanning electron microscopy and transmission electron microscopy. The plasma treatment was modified to introduce controlled levels of defects and functionalities to the graphene samples to give tunable properties. The elemental composition and structure were investigated by XPS and micro Raman spectroscopy. The XPS study showed that there was a slight variation in the sp2/sp3 hybridization ratio between the plasma-treated samples and the pristine sample. Kelvin probe measurements were carried out on all the multilayer graphene samples and indicated a slight variation in the work function of the graphene samples after plasma treatment.

A Distributed MIMO Radar With Joint Optimal Transmit and Receive Signal Combining

Abstract: Multiple-input multiple-output (MIMO) radar systems are popular for their ability to mitigate the target radar cross section fluctuations and null Doppler. However, MIMO radar fundamentally suffers from a notable signal-to-noise ratio (SNR) loss compared to an ideal phased-array (PA) radar. In order to overcome this drawback, a distributed MIMO radar scheme with joint optimal transmit and receive signal combining method is proposed in this work. In view of the optimality, the proposed scheme outperforms the most popular combining methods of MIMO radar addressed in the literature. Also, the proposed scheme performs same as the ideal PA radar in case of the nonfluctuating target. In case of fluctuating targets, the proposed scheme outperforms PA radar at high SNR.

Evolution of peptide nucleic acid with modifications of its backbone and application in biotechnology.

Abstract: Peptide nucleic acids (PNAs) are getting prodigious interest currently in the biomedical and diagnostic field as an extremely powerful tool because of their potentiality to hybridize with natural nucleic acids. Although PNA has strong affinity and sequence specificity to DNA/RNA, there is a considerable ongoing effort to further enhance their special chemical and biological properties for potential application in numerous fields, notably in the field of therapeutics. The toolbox for backbone modified PNAs synthesis has been extended substantially in recent decades, providing a more efficient synthesis of peptides with numerous scaffolds and modifications. This paper reviews the various strategies that have been developed so far for the modification of the PNA backbone, challenging the search for new PNA systems with improved chemical and physical properties lacking in the original aegPNA backbone. The various practical issues and limitations of different PNA systems are also summarized. The focus of this review is on the evolution of PNA by its backbone modification to improve the cellular uptake, sequence specificity, and compatibility of PNA to bind to DNA/RNA. Finally, an insight was also gained into major applications of backbone modified PNAs for the development of biosensors.