Electrical discharge machining (EDM) is much preferred in modern precision-manufacturing industries owing to its ability to machine any metal regardless of its hardness. However, its constraint is that the selected metal should be an electrically conductive material. For the present investigation, an Inconel 718 alloy was selected for EDM, using a TiB2-Cu electrode made with powder metallurgy. Input factors, namely, the pulse current (Ip), pulse-on time (Ton) and gap voltage (Gv) were selected and their output responses were the surface roughness (SR) and material-removal rate (MRR). For the response surface, the Box Behnken technique was preferred when designing the experiments (DoE). An ANOVA test was performed to understand the influence of the selected input factors on the SR and MRR. The RSM integrated with a grey relational analysis (GRA) revealed that the optimal input parameters for better machining characteristics were: Ip = 10 A, Ton = 40 µs and Gv = 50 V. Besides, the results also showed that the pulse current more significantly influenced the output responses than the other parameters. Moreover, an increase in the gap voltage caused surface irregularities on the machined surface. Surface morphology of the machined surfaces was analysed through SEM and EDAX. Moreover, a certain amount of tool-material transfer was noted with the EDAX analysis.

A research study was conducted for summer paddy area estimation in Needamangalam and Mannargudi blocks of Cauvery delta zone of Tamil Nadu using Sentinel-2A satellite data. Optical data reflects the biological features of objects and provides spectrum information about the surface. Sentinel-2A satellite data were obtained for the study area during summer seasonand processed using ENVI Software. The paddy area was derived from the processed data using ground truth points collected during the cropping period of the study area. The summer paddy cultivating area in the Needamangalam and Mannargudi blocks of the Cauvery delta zone was estimated as 8082 ha. Needamangalam and Mannargudi blocks are having 5766.25 and 2315.75 ha, respectively as summer paddy area Accuracy assessment of the classification was carried out using the confusion matrix for the collected ground truth points and the overall classification accuracy was 89.6 percent with a kappa scoreof 0.79.

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