Faculty Publications
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Item Mechanical and Thermal Properties of Sisal Fiber-Based Composites(wiley, 2021) Mishra, V.; Agrawal, A.; Chandraker, S.; Sharma, A.Natural fibers have attracted the scientific community toward their usage as reinforcement in polymeric composites mainly because of multiple benefits such as low cost, huge/easy availability, easy processing, and growing concern toward environmental awareness as they are biodegradable. Reinforcing natural fibers is an efficient approach toward reducing the consumption of nonbiodegradable plastic material. Also, natural fibers are promising reinforcing materials that can replace different synthetic fibers. Among the various natural fibers available, sisal fiber as reinforcement in a polymeric matrix is a strong competitor. Sisal fiber has several advantages like they are the widely used natural fiber and has the second-largest consumption across the world after cotton. It has high strength with good durability. It also has a good percentage of elongation before the break and does not deteriorate quickly in salty water. These fibers are smooth and straight with a high degree of inflexibility. Sisal represents around 2% of the total cultivation among plant fibers. In this regard, the present chapter focuses on sisal fiber as reinforcement with different polymeric matrices. The main emphasis is on the mechanical and thermal behavior of composite understudy and applications of this category of composites in various fields. A review of selected work on the research of sisal fiber with polymer matrix is the content of this chapter. © 2022 WILEY-VCH GmbH, Boschstr. 12, 69469 Weinheim, Germany.Item Physical, mechanical and sliding wear behavior of solid glass microsphere filled epoxy composites(Elsevier Ltd, 2018) Agrawal, A.; Chandraker, S.; Sharma, A.Performance of epoxy based composites filled with micro-size solid glass microsphere (SGM) is reported in this work. The main emphasis of the present work is on the common trends detected in properties of epoxy/SGM composites. For physical property, densities of all the fabricated samples were presented.Glass micro-sphere filled epoxy composites haveless porosity. They also exhibit improvedmicro-hardness, flexural and impact strength, though tensile strength is compromised marginally. Further, sliding wear performance of the fabricated composites with respect to filler content, sliding velocity and applied force were studied.With improved physical, mechanical and sliding wear, the presently fabricated composites found its potential application where wear predominated. © 2018 Elsevier Ltd. All rights reserved.Item Inner Attention Based bi-LSTMs with Indexing for non-Factoid Question Answering(Institute of Electrical and Electronics Engineers Inc., 2018) Sharma, A.; Harithas, C.In this paper, we focussed on non-factoid question answering problem using a bidirectional LSTM with an inner attention mechanism and indexing for better accuracy. Non factoid QA is an important task and can be significantly applied in constructing useful knowledge bases and extracting valuable information. The advantage of using Deep Learning frameworks in solving these kind of problems is that it does not require any feature engineering and other linguistic tools. The proposed approach is to extend a LSTM (Long Short Term Memory) model in two directions, one with a Convolutional layer and other with an inner attention mechanism, proposed by Bingning Wang, et al., to the LSTMs, to generate answer representations in accordance with the question. On top of this Deep Learning model we used an information retrieval model based on indexing to generate answers and improve the accuracy. The proposed methodology showed an improvement in accuracy over the referred model and respective baselines and also with respect to the answer lengths used. The models are tested with two non factoid QA data sets: TREC-QA and InsuranceQA. © 2018 IEEE.Item Reconstruction of Edges from Fan-Beam Projections(Institute of Electrical and Electronics Engineers Inc., 2018) Narasimhadhan, A.V.; Sharma, A.; Koolagudi, S.G.; Naganjaneyulu, G.V.S.S.K.R.; Avinash, S.; Peddireddy, V.; Kishan, N.B.; Rajan, J.The goal of computerised tomography is to reconstruct cross sectional image of the object under consideration from it's projections whereas edge detection is an image analysis problem of utmost importance in medical imaging to outline the boundaries of tumours, bones etc. In this paper, a technique to reconstruct the edges directly from fan-beam projections, using the Marr-Hildreth operator, is presented. To obtain the edge map of object under consideration, the divergent beam transform of Marr-Hildreth operator is convolved with ramp filter to yield an edge reconstruction filter which is finally convolved with the acquired fan-beam projections and back-projected, resulting in a convolution back-projection, to reconstruct the edges. The paper also discusses about the utilisation of state-of-the-art Noo's algorithm to reconstruct the edges directly from equi-angular fan beam projections. Finally, the proposed technique is simulated to make relevant conclusions and inferences. © 2018 IEEE.Item Mechanical and Thermal Behaviour of Epoxy/Hexagonal Boron Nitride/Short Sisal Fiber Hybrid Composites(Institute of Physics Publishing helen.craven@iop.org, 2020) Agrawal, A.; Chandraker, S.; Sharma, A.Hybrid composite i.e. surface modified hexagonal boron nitride (hBN) and short sisal fiber reinforced in epoxy matrix is fabricated using hand lay-up method. The effect of surface modified hBN filler and sisal fiber content on mechanical and thermal properties of epoxy based hybrid composites were investigated in this paper. The main aim of the investigation is to develop a material which can found its application in microelectronic components. As per the requirement of microelectronic industry, the material should possess high thermal conductivity. Hence, thermal conductivity of epoxy increases with increase in hexagonal boron nitride content. Inspite of insulative nature of sisal fiber, the study shows that its inclusion in combination with hBN enhances the thermal conductivity if the content of both the fillers were properly selected. Other thermal property like coefficient of thermal expansion and glass transition temperature appreciably improves when combination of fillers were added in epoxy matrix. Mechanical properties under study i.e. tensile strength and compressive strength also enhances when combination of sisal fiber and hBN were incorporated as compared to when single filler hBN were used. Hence, usage of hybrid filler as reinforcement in epoxy improve overall mechanical and thermal property of the developed material. © 2020 Published under licence by IOP Publishing Ltd.Item Design and Development of Efficient Under-Drainage System for Lined Canals(Springer Science and Business Media Deutschland GmbH, 2021) Sharma, A.; Das, B.B.Under-drainage system for lined canal is present beneath the canal bed to drain off the water present over there. It consists of longitudinal and transverse perforated drain pipes along with the arrangement of pressure relief valves. Cases of failure of lining of canal are there due to inconsistency in under-drainage system. Performance of geocell is exceptionally well in soil compaction, slope stabilization, earth retention and as reinforcement in case of retaining structure, road construction and railway embankments. Contrary to other researches, here performance of geocell as reinforcement of buried pipe under canal bed is investigated. Experimental study is carried out on canal model and on an under-drainage system. Strain in the buried pipe is observed due to application of various loading patterns on canal model. For sustained loading, 29% increase in strain is observed in pipe buried in unreinforced soil as compared to 18% in pipe buried in reinforced soil. For maximum loading almost three times more strain is stored in pipe in unreinforced soil. Yield is also observed in pipe without geocell, whereas at same loading no such behaviour is observed in pipe with geocell. It is reported that geocell can act as reinforcement for buried drain pipes under canal bed, and this helps in making under-drainage system efficient. © 2021, Springer Nature Singapore Pte Ltd.Item Physical and mechanical properties of epoxy reinforced with pistachio shell particulates(American Institute of Physics Inc., 2021) Chandraker, S.; Agrawal, A.; Prakash, P.; Khan, I.A.; Sharma, A.Recently, natural fillers have gain huge interest among the academic researchers and scientists to be used as potential reinforcement material in polymeric matrix composites. The various reasons which attract the scientific community toward it usage in polymer composites are its low cost, ample availability, easy processing and the most important is the growing concern towards environmental awareness as they are bio-degradable. Reinforcing natural fillers is also an efficient approach towards waste management as most of the promising natural fillers were dumped if not used. Following the similar trend, an attempt has been made to utilize pistachio shells as a filler material in polymeric resin for developing a composite body. Pistachio shell with particle size 75 micron is used with epoxy matrix in present investigation. Six sets of epoxy based composites are fabricated using hand lay-up method by varying the filler content upto 30 wt. %. Density of the composites is evaluated using Archimedes principle. Micrographs are taken to visualize the compatibility between filler and matrix body. Tensile strength, compressive strength, flexural strength and hardness are the various mechanical properties evaluated of the developed materials. From the experimental analysis, it has been found that, all the mechanical properties of the composite under consideration increases with filler content. Though increase in density is also observed with filler loading but the increment is marginal. On the basis of experimental findings, it can be concluded that the developed material can be gainfully found its application in light duty structures. © 2021 Author(s).Item Design and Implementation of a System for Vehicle Accident Reporting and Tracking(Institute of Electrical and Electronics Engineers Inc., 2022) Dankan Gowda, V.D.; Sharma, A.; Naik, A.S.; Meena, R.S.; Kudari, J.M.; Purushotham, S.Population growth and per capita income have contributed to increasing vehicle ownership and presence on roads worldwide. Increasing traffic on roads is one of the prime causes of road accidents. A large proportion of people die prematurely in road accidents. It is almost impossible to predict before the accident happens. Also, there may be some accident prevention mechanisms and early warning systems, but it is hard to avert road accidents wholly. This paper has explained in detail, the designing and implementation of a crash notifier system. © 2022 IEEE.Item An Improved ResNet-50 Neural Network Design for PV Panel Image Classification(Springer Science and Business Media Deutschland GmbH, 2025) Kumar, A.; Kashyap, Y.; Sharma, A.The increasing popularity of photovoltaic (PV) setups stems from their capacity to generate clean and cost-effective electricity. However, various factors can either totally or partially disrupt the production of PV panels. To address this challenge, this study proposes a ResNet-50 model with dynamically adjusted hyperparameters to classify real-time captured images of PV panels into efficient and non-efficient categories. The hyperparameter tuning within the ResNet-50 model is conducted across three distinct cases, revealing that the most optimal classification results are achieved with the following settings: 50 epochs, a learning rate of 0.001, and a batch size of 32. The highest weighted average metrics, including accuracy (96%), recall (96%), precision (97%), and F1-score (96%), were obtained under these settings. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2025.Item Influence of masonry infill on fundamental natural frequency of 2D RC frames(2010) Chethan, K.; Ramesh Babu, R.; Venkataramana, K.; Sharma, A.Reinforced Concrete (RC) framed structures with Un-Reinforced Masonry (URM) infill panels form a major portion of all the RC framed structures worldwide. The URM panels are considered as non-structural members, which is fairly good assumption under gravity loads, however, it is not the same under lateral forces. Under seismic loads, the stiffness additions due to infill panels modify the dynamic behavior of the structure significantly by altering the frequency of the structure. A research project has been taken up at Earthquake Engineering and Vibration Research Centre (EVRC), Central Power Research Institute (CPRI), Bangalore to investigate the influence of masonry infill on fundamental natural frequency of RC frames. 2D RC frames of one bay and two bay having single storey, double storey and three storeys are cast and tested for bare frame and many combinations of URM infill panels. Tri-axial shake table is used for testing. The details of the numerical analysis and experimentation carried out in the research project are brought out in this paper.