Faculty Publications
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Item Monitoring Spatial and Temporal Scales of Shoreline Changes in the Cuddalore Region, India(Elsevier, 2018) Subbarayan, S.; Kulithalai Shiyam Sundar, K.S.S.; Vishnuprasath, S.R.Coastal zones are constantly undergoing changes in shape and environment due to natural processes and anthropogenic interventions. The study of shoreline change has become a matter of great concern in recent years. The measurement of shorelines is a key factor in coastal zone construction. A shoreline change study was carried out for a 33-km stretch of the Cuddalore coast between Gadilam and the Vellar River. Satellite images (2000, 2005, 2010, and 2015) were taken as an input dataset in a GIS platform. Automatic shoreline delineation was attempted by a masking technique using ENVI software. In this study, the modification of normalized difference water index (MNDWI) method extracted the raster shoreline-based contrast value of coastal pixels and thresholding techniques for segmenting water and land regions. DSAS software and reference digitized shoreline boundary data were used for the analysis of shoreline changes. End point rate (EPR) and net shoreline movement determination showed the northern part of the Uppanar River mouth under erosion (region A to C and E) and sediment deposition at an accretion rate of 7.6. m/year from EPR and 114. m from NSM. The maximum shoreline erosion rate was -. 3.8. m/year from EPR and -. 57. m from NSM. From these attempts and results, a methodical approach for detection and monitoring of shoreline changes on spatial and temporal scales of interest have been suggested. © 2019 Elsevier Inc. All rights reserved.Item Solar Radiation Assessment and Forecasting Using Satellite Data(Springer Nature, 2019) Masoom, A.; Kashyap, Y.; Bansal, A.Since the availability of ground data is very sparse, satellite data provides an alternative method to estimate solar irradiation. Satellite data across various spectral bands may be employed to distinguish weather signatures, such as dust, aerosols, fog, and clouds. For a tropical country like India, which is potentially rich in solar energy resources, the study of these parameters is of crucial importance from the perspective of solar energy. Furthermore, a complete utilization of the solar energy depends on its proper integration with power grids. Because of its variable nature, incorporation of photovoltaic energy into electricity grids suffers technical challenges. Solar radiation is subjected to reflection, scattering and absorption by air molecules, clouds, and aerosols in the atmosphere. Clouds can block most of the direct radiation. Modern solar energy forecasting systems rely on real-time Earth observation from the satellite for detecting clouds and aerosols. © 2019, Springer Nature Singapore Pte Ltd.Item Monitoring Spatial and Temporal Scales of Shoreline Changes in the Cuddalore Region, India(Elsevier, 2019) Subbarayan, S.; Kulithalai Shiyam Sundar, K.S.S.; Vishnuprasath, S.R.Coastal zones are constantly undergoing changes in shape and environment due to natural processes and anthropogenic interventions. The study of shoreline change has become a matter of great concern in recent years. The measurement of shorelines is a key factor in coastal zone construction. A shoreline change study was carried out for a 33-km stretch of the Cuddalore coast between Gadilam and the Vellar River. Satellite images (2000, 2005, 2010, and 2015) were taken as an input dataset in a GIS platform. Automatic shoreline delineation was attempted by a masking technique using ENVI software. In this study, the modification of normalized difference water index (MNDWI) method extracted the raster shoreline-based contrast value of coastal pixels and thresholding techniques for segmenting water and land regions. DSAS software and reference digitized shoreline boundary data were used for the analysis of shoreline changes. End point rate (EPR) and net shoreline movement determination showed the northern part of the Uppanar River mouth under erosion (region A to C and E) and sediment deposition at an accretion rate of 7.6m/year from EPR and 114m from NSM. The maximum shoreline erosion rate was −3.8m/year from EPR and −57m from NSM. From these attempts and results, a methodical approach for detection and monitoring of shoreline changes on spatial and temporal scales of interest have been suggested. © 2019 Elsevier Inc. All rights reserved.Item Quantification and morphology studies of nanoporous alumina membranes: A new algorithm for digital image processing(2013) Choudhari, K.S.; Jidesh, P.; Sudheendra, P.; Kulkarni, S.D.A new mathematical algorithm is reported for the accurate and efficient analysis of pore properties of nanoporous anodic alumina (NAA) membranes using scanning electron microscope (SEM) images. NAA membranes of the desired pore size were fabricated using a two-step anodic oxidation process. Surface morphology of the NAA membranes with different pore properties was studied using SEM images along with computerized image processing and analysis. The main objective was to analyze the SEM images of NAA membranes quantitatively, systematically, and quickly. The method uses a regularized shock filter for contrast enhancement, mathematical morphological operators, and a segmentation process for efficient determination of pore properties. The algorithm is executed using MATLAB, which generates a statistical report on the morphology of NAA membrane surfaces and performs accurate quantification of the parameters such as average pore-size distribution, porous area fraction, and average interpore distances. A good comparison between the pore property measurements was obtained using our algorithm and ImageJ software. This algorithm, with little manual intervention, is useful for optimizing the experimental process parameters during the fabrication of such nanostructures. Further, the algorithm is capable of analyzing SEM images of similar or asymmetrically porous nanostructures where sample and background have distinguishable contrast. Copyright © Microscopy Society of America 2013.Item Data transfer using MCM code(Institute of Electrical and Electronics Engineers Inc., 2016) Manishkumar, S.P.; Agarawal, D.J.; Tom, A.J.; Chaithya, G.R.; Varambally, S.Multicolored Matrix (MCM) Code is a two-dimensional color coded matrix. It consists a sequence of images rendered at an optimum frame rate to transfer simple data between portable devices such as a mobile phone. We introduce an untried channel-less short range communication technology, designed with limitless storage capacity, great structural stability and flexibility due to which it can work in harsh lighting environments and still combat readability issues in the decoding process. The idea is inspired by the already existing QR code. Our method has various code types in terms of number of colors and size of matrix depending on length of the data. This paper introduces our new idea of data transfer, the technical features of the code along with the encoding-decoding techniques, bit error rates and future scope of improvements for the idea. © 2016 IEEE.Item Image processing approach to diagnose eye diseases(Springer Verlag service@springer.de, 2017) Prashasthi, P.; Shravya, K.S.; Deepak, A.; Mulimani, M.; Shashidhar, K.G.Image processing and machine learning techniques are used for automatic detection of abnormalities in eye. The proposed methodology requires a clear photograph of eye (not necessarily a fundoscopic image) from which the chromatic and spatial property of the sclera and iris is extracted. These features are used in the diagnosis of various diseases considered. The changes in the colour of iris is a symptom for corneal infections and cataract, the spatial distribution of different colours distinguishes diseases like subconjunctival haemorrhage and conjunctivitis, and the spatial arrangement of iris and sclera is an indicator of palsy. We used various classifiers of which adaboost classifier which was found to give a substantially high accuracy i.e., about 95% accuracy when compared to others (k-NN and naive-Bayes). To enumerate the accuracy of the method proposed, we used 150 samples in which 23% were used for testing and 77% were used for training. © Springer International Publishing AG 2017.Item Compressed Sensing for Energy and Bandwidth Starved IoT Applications(Institute of Electrical and Electronics Engineers Inc., 2018) Ramachandra, G.; Bhat, M.S.Ensuring security through the use of video surveillance cameras at public places is becoming attractive these days, thanks to the efficient compression, transmission and storage schemes. To up-scale the surveillance mechanism to large sensor networks, it is imperative that the applications become compatible to wireless sensor networks using Internet of Things (IoT) infrastructure. IoT nodes are generally energy and bandwidth-limited owing to their small size and large scale deployment. Therefore, any image/video acquisition application using IoT infrastructure should function within these constraints. Compressed sensing (CS) is one such paradigm that uses simultaneous sensing and compression and provides a technique for efficient image/video acquisition. This paper investigates the use of compressed sensing for image acquisition in IoT based applications that suffer from energy, bandwidth and storage limitations. © 2018 IEEE.Item Evaluation of ultrasonic sensor in robot mapping(Institute of Electrical and Electronics Engineers Inc., 2019) Nair, S.K.A.; Joladarashi, S.; Ganesh, N.This paper presents the simulation and experimental investigation on mapping done using ultrasonic sensor(HC-SR04). Issues related to exploration, mapping and localization are discussed. Kobuki base with three ultrasonic sensors was kept as robot mobile base platform. A 2D occupancy grid map is updated by the robot when it moves and collects information from ultrasonic sensor. The sensor being noisy in nature generates unwanted ghost points. This results in outliers in the map especially in corners of the environment due to specular reflections. The issues like outliers are dealt with image processing techniques. © 2019 IEEE.Item Development of low-cost real-time driver drowsiness detection system using eye centre tracking and dynamic thresholding(Springer Verlag service@springer.de, 2020) Khan, F.; Sharma, S.One in every five vehicle accidents on the road today is caused simply due to driver fatigue. Fatigue or otherwise drowsiness, significantly reduces the concentration and vigilance of the driver thereby increasing the risk of inherent human error leading to injuries and fatalities. Hence, our primary motive being - to reduce road accidents using a non-intrusive image processing based alert system. In this regard, we have built a system that detects driver drowsiness by real time tracking and monitoring the pattern of the driver’s eyes. The stand alone system consists of 3 interconnected components - a processor, a camera and an alarm. After initial facial detection, the eyes are located, extracted and continuously monitored to check whether they are open or closed on the basis of a pixel-by-pixel method. When the eyes are seen to be closed for a certain amount of time, drowsiness is said to be detected and an alarm is issued accordingly to alert the driver and hence, prevent a casualty. © Springer Nature Switzerland AG 2020.Item Estimation of Tyre Pressure from the Characteristics of the Wheel: An Image Processing Approach(Springer, 2020) Vineeth Reddy, V.B.; Ananda Rao, H.; Yeshwanth, A.; Ramteke, P.B.; Koolagudi, S.G.Improper tyre pressure is a safety issue that falls prey to ignorance of users. But a drop in tyre pressure can result in the reduction of mileage, tyre life, vehicle safety and performance. In this paper, an approach is proposed to measure the tyre pressure from the image of the wheel. The tyre pressure is classified into under pressure and normal pressure using load index, tyre type, tyre position and ratio of compressed and uncompressed tyre radius. The efficiency of the feature is evaluated using three classifiers namely Random Forest, AdaBoost and Artificial Neural Networks. It is observed that the ratio of radii plays a major role in classifying the tyres. The proposed system can be used to obtain a rough idea on whether the tyre should be refilled or not. © 2020, Springer Nature Singapore Pte Ltd.