Browsing by Author "Saraah Imran"

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A Novel Deep Learning-based Landsat 7 ETM+ Multi-Spectral to Hyperspectral Reconstruction Model: Application for Water Bodies in an Indian Region
(Institute of Electrical and Electronics Engineers Inc., 2024) Saraah Imran; Subhojit Mandal; Ajanta Goswami; Mainak Thakur; Ashwani Raju
Hyperspectral (HS) remote sensing has the capacity to provide finer spectral information and better identification of objects while multispectral (MS) data are more readily available but with fewer bands. In absence of HS data, spectral reconstruction from MS to HS data can be considered in order to enhance the applicability of HS data. In this study, a deep learning-based Multi-Head Attention enabled Multi-Layer Perceptron (MHA-MLP) model is developed to reconstruct a scene of EO-1 Hyperion (HS) from a Landsat 7 ETM+ (MS) image. The reconstruction is also done using Multi-Layer Perceptron (MLP) and Transformer models. The reconstructed data from the three models is studied for water body locations in Betul, Madhya Pradesh, India. The results are analysed by comparative study of the spectra and calculation of standard statistical metrics. The reconstructed spectra from the MHA-MLP are found to follow the original HS spectra more closely than the other models and show the best values in the statistical metrics. Hence, The MHA-MLP model is found to be the best HS reconstructor model when compared to MLP and Transformer models. The reconstructed spectra are capable of capturing the 670 nm notch important for the study of chlorophyll concentration. This model can be used for water quality assessment applications and can also be extended for other applications. © 2024 IEEE.
Geomorphological and mineralogical analysis of the lunar Robertson crater
(Elsevier Ltd, 2025) Ashwani Raju; Saraah Imran; Jiwantika Kumari; Ankit Kumar; Ramesh P. Singh
This study provides a comprehensive overview of the lunar Robertson crater of Copernican period located on the far side of the moon using multi-sensor satellite observations from combined Chandrayaan-I M3, LROC WAC Global Geomorphology and SELENE DTM mosaics. The analysis shows development of dynamic features, distribution of minerals, and topographic features during the crater formation. The crater preserves a complex geological evolution based on the mineralogical heterogeneity and distinct geomorphological features (such as accumulated melt flow at the crater floor, topographic undulations etc.) observed in a radial symmetry, which suggest formation through high energy impact processes. The detailed investigation of melt pool topography at the crater floor, highlights the formation and subsequent modifications of the transient cavity developed during simple to complex crater transition after the impact. The mineral species identified using the RELAB spectral library through the ‘spectral hourglass’ workflow show a distinct distribution, with Mg-spinel and olivine-rich lithologies concentrated in the central peak, while pyroxenes dominate the crater floor and surrounding rock rings. This pattern shows a complex mineral distribution, likely excavated from different depths as a result of the impact event. The dynamics of crater formation show a diameter respectively of 4.36 km and 5.73 km, assumed for chondrite and iron projectiles. Besides, CSFD measurements represent an absolute age of about 82 ± 4 Ma based on the 121 isochron fits to the differential data of post-impact craters that suggests recent resurfacing consistent with melt flow during the terminal stages of impact dynamics. © 2025 COSPAR