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Summary: The switched reluctance motor (SRM) is a prominent electrical machine drive with low cost and good performance in different drive applications. This machine's main drawbacks are torque ripple and flux ripple. However, the existing SRM‐operated direct torque control (DTC) Voltage vectors (VVs) give high torque ripples due to improper sector division and minimum selection of VVs switching states. On the other hand, a two‐level hysteresis torque band can result in torque ripples. Therefore, this paper proposed DTC using 16 partitions, active small and large VVs, and a multilevel hysteresis torque band (MHTB) strategy to mitigate the torque ripple further. More active VVs (i.e., 16) are employed in the modified sector‐based switching tables, suppressing the torque ripples. The proposed strategy is verified and validated using MATLAB/Simulink. The detailed result discusses the response of torque, flux, and speed of SRM. The DTC‐operated SRM drive experimental results prove the effective minimization of torque ripples in the proposed DTC compared to the existing DTC. [ABSTRACT FROM AUTHOR]

Robust data on the spatial distribution of land degradation is important for resource conservation planning. Spatial land degradation status of India was mapped using multi-temporal Linear Imaging Self Scanning Sensor (LISS-III) data acquired from Resourcesat-1/2 during 2005-2006 and 2015-2016 under the Natural Resources Census programme of the Indian Space Research Organisation. Heads-up on-screen visual interpretation of multi-season satellite data was carried out, supported by digital elevation model and other historical maps available. Visual interpretation cues were developed and employed across various partner institutions to achieve consistency in mapping. The outputs were subjected to two-stage quality check. Results indicate that the total land degradation of India was 91.2 M ha (27.77% of the geographical extent of the country) during 2015-2016 against 91.3 M ha during 2005-2006. During the ten-year period, there was an overall decrease of around 0.1 M ha in degraded land. However, noticeable intra- and inter-class changes were observed in land degradation during the ten-year period. Major reclamation was noticed in sand dunes which were converted into crop lands by levelling them. Substantial decrease in severity and extent of salt-affected soils was noticed in Uttar Pradesh. [ABSTRACT FROM AUTHOR]

Brachytherapy (BT) for locally advanced cervical cancer is vital for optimal outcomes. There is heterogeneity in brachytherapy treatment practice for cervical cancer across India. In an attempt to standardize various processes involved in cervical cancer brachytherapy, the expert members of the Indian Brachytherapy Society (IBS) developed a document related to radiation therapy treatment of cervical cancer with special emphasis on brachytherapy. The guidelines are based on high quality clinical evidence, expert opinion and consensus wherever evidence was lacking. The document provides a guide for external beam radiation and details of all the processes involved in high-dose-rate (HDR) brachytherapy including patient selection, preparation, principles and technique of BT applications, target and normal tissue definition, dose prescriptions, BT planning, reporting parameters, common complications of BT and their management, scope for research, etc. In summary, we present here practical tips and tricks, recording and reporting of cervical cancer brachytherapy, which can be implemented in various clinical environments and forms the basis of this report. [ABSTRACT FROM AUTHOR]

Reliable mapping of soil organic carbon (SOC) and Soil Inorganic Carbon (SIC) densities and estimates of their pool size are important from global warming perspective to understand the sequestration potential and losses. In this study, first spatially explicit mapping of SOC and SIC at 250 m resolution and an estimate of their pool size in India was undertaken using a large number of remote sensing derived data layers and data mining approach. The SOC and SIC densities up to 100 cm depth or paralithic contact (whichever is shallower) were estimated for 1198 soil samples located across India using a stratified random sampling that integrated land use, soil, topography and agro-ecological regions. Using Random forests (RF) based spatial prediction procedure with climatic, land cover, rock type, soil type, multi-year NDVI, irrigation status as independent input variables, models for predicting carbon density at 250 m spatial resolution were developed. For modelling with RF algorithm, about 898 soil profile observations (75% observations) were used, while the rest of 300 (25% of total observations) were used for validation. It was observed that the data distribution of sample points don't have significant influence on RF model predictions. The relationship between observed and predicted values was characterized by Mean Squared Deviation (MSD) and Root Mean Squared Error (RMSE) parameters. The SOC, SIC and total soil carbon pool size of India has been estimated at 22.72 ± 0.93 Pg,12.83 ± 1.35 Pg and 35.55 ± 1.87 Pg, respectively, which are comparable to previous studies while providing first spatially explicit 250 m map of their distribution. The spatial distribution indicates that majority of the carbon stock resides in the northern part of India. The soil carbon stock of eastern India has contribution from organic carbon, while the western portion has contribution mainly from inorganic carbon. [ABSTRACT FROM AUTHOR]