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Publication Metadata only Understanding the Influence of Film Thickness on rGO-Based Flexible Capacitive Leaf Wetness Sensors for In-Situ Agriculture Applications(IEEE, 01-07-2025) Yogi, Pooja; Yadav, Rohit; Kumari, Kusum; Borkar, Hitesh; Roy, Anil; Palaparthy, Vinay; DA-IICT, GandhinagarIntegrated plant disease management is pivotal in abating crop loss. For this purpose, leaf wetness sensors (LWSs) are widely used to measure the leaf wetness duration. This work focuses on fabricating the LWS on flexible polyimide substrates and understanding its sensor transfer characteristics using reduced graphene oxide (rGO) as the sensing film with varying thickness. For this purpose, three different concentrations, viz, 0.001 mg (Device A), 1 mg (Device B), and 10 mg (Device C) of rGO are dispersed in 0.5 mL deionized water, and these are drop-casted on the fabricated LWS. Subsequently, sensor properties such as response, recovery/recovery time, hysteresis, and temperature effects are studied. Initial laboratory readings demonstrate that the fabricated LWS response for devices A, B, and C is 607866%, 6541%, and 780%, sensing area wetness, respectively. Further, the response times for devices A, B, and C are 10, 15, and 6 s, respectively. Interestingly, the recovery times of devices A, B, and C are approximately 15, 16, and 2462 s, respectively. Further, it has been observed that over the temperature range of 30 °C–60 °C, the sensor response changes by 2%, 5%, and 17% for devices A, B, and C, respectively.Publication Metadata only Detection and localization of copy-move tampering along with adversarial attack in a digital image(Springer, 02-07-2025) Diwan, Anjali; Roy, Anil; DA-IICT, GandhinagarPublication Metadata only A novel method for detecting light source for digital images forensic(De Gruyter, 01-06-2011) Agrawal, Rohin; Mitra, Suman; Mitra, Suman; Mitra, Suman; Roy, Anil; Roy, Anil; DA-IICT, Gandhinagar; Agrawal, Rohin (200501187)Manipulation in image has been in practice since centuries. These manipulated images are intended to alter facts � facts of ethics, morality, politics, sex, celebrity or chaos. Image forensic science is used to detect these manipulations in a digital image. There are several standard ways to analyze an image for manipulation. Each one has some limitation. Also very rarely any method tried to capitalize on the way image was taken by the camera. We propose a new method that is based on light and its shade as light and shade are the fundamental input resources that may carry all the information of the image. The proposed method measures the direction of light source and uses the light based technique for identification of any intentional partial manipulation in the said digital image. The method is tested for known manipulated images to correctly identify the light sources. The light source of an image is measured in terms of angle. The experimental results show the robustness of the methodology. Keywordsimage forensics�manipulation�least square approximation�surface normals�decorrelation�noise filterPublication Metadata only Investigating an Impact of Leaf Bending Radius and Angle for Flexible Leaf Wetness Sensor(IEEE, 01-03-2024) Khaparde, Priyanka; Patle, Kamlesh S; Borkar, Hitesh; Gangwar, Jitendra; Roy, Anil; Palaparthy, Vinay; DA-IICT, Gandhinagar; Patle, Kamlesh S (202121017)It is pivotal to monitor and examine the plant disease during in situ measurements to abate the crop loss. For this purpose, leaf wetness sensors (LWS) are widely used. However, for the LWS during in situ measurements, operational exposure is always a concern considering the plant growth at different stages. During the plant growth, the stem angle changes and even the leaf canopy bends either inward or outward due to environmental factors or physical trauma. Thus, LWS placed on the leaf canopy may produce erroneous results. In this letter, we have examined the effect of leaf bending radius (outward or inward) and angle (from 0� to 90�) on the flexible LWS fabricated on the polyamide substrates. LWS comprises of interdigitated electrodes (IDEs) having interelectrode spacing 0.05 cm. Fabricated LWS are 3.5 cm long and 1.5 cm wide in dimension. We have used the two LWS viz. one bare IDEs and another with molybdenum disulfide (MoS2) coated LWS. Lab experiments indicated that sufficient wetness remained on the bare IDEs and MoS2-coated IDEs till 40� and 70� of bending angle, respectively. Subsequently, when the LWS are bended outward or inward, bare IDEs and MoS2-coated IDEs retain water molecules till 0.7 and 1 cm, respectively, when bended from its initial length (3.5 cm).Publication Metadata only Keypoint based comprehensive copy-move forgery detection(IET, 01-12-2021) Diwan, Anjali; Sharma, Rajat; Mitra, Suman; Mitra, Suman; Mitra, Suman; Roy, Anil; Roy, Anil; DA-IICT, Gandhinagar; Diwan, Anjali (201521013); Sharma, Rajat (201811045)Verifying the authenticity of a digital image has been challenging problem. The simplest of the image tampering tricks is the copy-move forgery. In copy-move forgery copied portion of the image is pasted on another part of the same image. Geometrical transformations are used on the copied portions of the image before pasting it for the tampered image to look realistic and visually convincing. To make it more complex, other processing approaches may also be applied in the forged region for hiding traces of forgery. These processings are the scale, rotation, JPEG compression, and AWGN. In this paper, an approach based on features of the CenSurE keypoint detector and FREAK descriptor is proposed. This combination has novelty in itself as it has never been used for this purpose before to the best of authors' literature studies. CenSurE detectors are fast and give stable and accurate output even in the case of rotated images, which we club with binary descriptor FREAK. Hierarchical clustering and Neighbourhood search is applied in such a way that it can locate and detect multiple copy-move forgeries. The authors are hopeful that the proposed approach may be used in real-time image authentication and copy-move forgery detection.Publication Metadata only Evolution of Dew and Rain Water Resources in Gujarat (India) between 2005 and 2021(Preprint.org, 24-06-2024) Budhbhatti, Rupal; Muselli, Marc; Beysens, Daniel; Roy, Anil; Roy, Anil; DA-IICT, GandhinagarGlobal warming leads in general to a reduction in precipitations and non-rainfall water contributions such as dew. The present study, carried out in Gujarat (India) for 17 years between 2005 and 2021, shows however a rare increase of the rain falls and dew condensation, the latter related to an increase in relative humidity and a decrease in wind amplitudes. Rain was obtained from meteo stations. Dew was calculated from an energy model and meteo data from 15 meteo stations (14 in India and 1 in Pakistan) and compared to early and dedicated measurements in 13 sites. Maps of dew, rain and their relative contributions during the period are provided. They show that, while rain mainly occurs during the monsoon (June to September), dew forms during the dry season (October to April). This water resource was mapped over the Gujarat state of India by using a kriging process. According to the site, the dew/rain ratios can represent between 4.6% (Ahmedabad) to 37.2% (Jamnagar) on the whole period of 17 years. This positive evolution, which is observed since 2015-2017, is likely to continue in the future.Publication Metadata only CNN-Keypoint Based Two-Stage Hybrid Approach for Copy-Move Forgery Detection(IEEE, 21-03-2024) Diwan, Anjali; Roy, Anil; Roy, Anil; DA-IICT, GandhinagarAuthenticating digital images poses a significant challenge due to the widespread use of image forgery techniques, including copy-move forgery. Copy-move forgery involves copying and pasting portions of an image within the same image while applying geometric transformations to make the forged image appear genuine. Furthermore, additional processing techniques such as additive noise scaling, JPEG compression, and rotation can be employed to further conceal evidence of forgery. These factors contribute to the complexity of detecting and verifying the authenticity of digital images. The proposed work uses a combination of the CenSurE keypoint detection and a CNN architecture to detect and localize copy-move forgery in digital images. The use of CNN architecture allows the algorithm to update its learning via training data repeatedly, making it a data-driven approach. By combining keypoints with CNN features, the proposed approach can enhance the detection of copy-move forgery even in the presence of attacks such as geometrical transformations, scale, and rotation. Additionally, the proposed approach can effectively handle post-processing operations such as JPEG compression, additive noise, image blur, colour reduction, brightness change, and contrast adjustment. One important aspect of the proposed approach is its ability to handle images with different textures, including smooth and self-similar structural images with dense textures. The proposed approach can produce stable results in images with various attacks, making it a functional and reliable tool for detecting copy-move forgery in a diverse range of forged images. The proposed approach represents an important contribution to the field of multimedia forensics, providing an effective and reliable means of detecting and localizing copy-move forgery in digital images.Publication Metadata only Superpixel-Driven Optimized Wishart Network for Fast PolSAR Image Classification Using Global k-Means Algorithm(IEEE, 01-01-2020) Gadhiya, Tushar; Roy, Anil; Roy, Anil; DA-IICT, GandhinagarLimitation of optical remote sensing technology gave rise to synthetic aperture radar (SAR) imaging. SAR is a microwave imaging technique, which promises to have a long-range propagation characteristic allowing imaging under harsh weather conditions or in hostile lighting situation. This has opened up a domain of classification using polarimetric SAR (PolSAR) images. In this article, we propose a fast PolSAR image classification algorithm, which uses not only pixel-based feature but also spatial features around each pixel. This is achieved by introducing superpixel-driven optimized Wishart network. The first improvement suggested in this article is to take advantage of a fast global k-means algorithm for obtaining optimal cluster centers within each class. It uses real-valued vector representation of PolSAR coherency matrix along with fast matrix inverse and determinant algorithms to reduce computational overhead. Our method then exploits the information of neighboring pixels by forming a superpixel so that even a noisy pixel may not be assigned a wrong class label. The proposed network uses dual-branch architecture to efficiently combine pixel and superpixel features. We concluded that our proposed method has better efficiency in terms of classification accuracy and computational overhead compared with other deep learning-based methods available in the literature.Publication Metadata only Optimized Wishart Network for an Efficient Classification of Multifrequency PolSAR Data(IEEE, 01-11-2018) Gadhiya, Tushar; Roy, Anil; Roy, Anil; DA-IICT, Gandhinagar; Gadhiya, Tushar (201621009)Publication Metadata only CSD Type Family Solar Drying Technology and its Potential Impact on Rural Development and Nutrition - a Case Study(CCSE, 01-04-2014) Sinha, Sangeeta; Singh, SNP; Roy, Anil; Roy, Anil; DA-IICT, GandhinagarGlobalization has adversely affected development of rural areas in developing countries. Rural areas are unable to absorb new technologies due to low literacy rates. Local Products, mostly from agricultural produces, are increasingly replaced by cheaper products from organized mechanized farming from one or the other corner of the globe. In this paper, family type cabinet solar dryer designs are presented in commensuration with the contemporary requirement of rural Bihar. Design objective includes simplification of technology and process, easy maintenance and low price to dry exotic produces which has significant export potential. Field trials are conducted, social surveys are undertaken and nutritional values of the products are determined in actual condition. Results indicate that simpler technology with state-of-art control of temperature by a combination of high heat capacity material and phase change material is most suitable to dry vegetables and spices, commonly called �Cash Crops�. Their nutritional values remain within 80% limits even after six months. The technology is appropriate as it uses local materials; sustainable as it is cost-effective and employment generating ability and; robust as it uses very simple way for controlled drying.