Faculty Publications
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Item Microstructural and Size Accuracy Study of Electrochemical Machined Aluminium Alloy Features(Springer Nature, 2019) Sahu, R.K.; Pal, V.K.; Kumar, P.The present work focuses on the machining of aluminium 6061 alloy workpiece electrodes using Electro-Chemical Machining (ECM) by varying the control parameters like voltage, feed rate and machining time. Scanning electron microscopy study is carried out to examine the microstructure of the craters of definite morphology machined on the workpiece. Optimum parameter settings to maximize the length, width and depth of the obtained features were studied individually through a parametric experimental design layout of Taguchi. The results reveal that the optimal parameter settings are found to be different for each performance objective. As a result, the grey Taguchi method has been adopted to convert the three objectives into a single objective and by considering the performance objectives concurrently, the process parameters were optimized. The favourable parameters to maximize the responses are determined to be voltage—15 V, feed rate—0.3 mm/min and machining time—5 min. Further, the effect of process parameters on the microstructure and size accuracy of the Al alloy features is studied. © 2019, Springer Nature Singapore Pte Ltd.Item Investigation on Corrosion Behavior of Polydimethylsiloxane and Nanofillers-Based Polymer Nanocomposite Coated Galvanized Iron(Springer, 2025) Kumar, P.; Kumar, S.; Ramesh, M.R.; Doddamani, M.The paper focuses on developing polydimethylsiloxane (PDMS) and nanofillers (ZnO and SiO2) based polymer nanocomposite solutions for coating galvanized iron (GI) using sol–gel dip coating method and investigating its corrosion behavior. The nanofillers in varying wt.% (0, 2, 4, 6, 8, and 10) are incorporated in the solution of PDMS and xylene for developing a nanocomposite coating solution. The solutions are characterized by pH, viscosity, and non-volatile matter. It is observed that all the solutions are basic. The viscosity (10.28–47.43%) and the non-volatile matter (8.06–15%) of the solutions are observed to be increasing with an increasing nanofiller % as compared to the base solution (PDMS and xylene). The developed solutions are coated on the GI substrate and tested for wettability, XRD, FTIR, and electrochemical responses. The wettability and the XRD tests confirm the hydrophobic and amorphous nature of the coated surface, respectively. The Si–O–Si groups are observed at 1088 cm−1. The electrochemical analysis shows that the impedance resistance of the coated surfaces is higher than that of the surface coated with the base solution. Further, the corrosion rate of the coated surfaces decreases with the % of the nanofillers. The coating with 10% nanofillers exhibited the highest impedance resistance and the lowest corrosion rate, finding applications in construction, marine, and naval. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2025.Item Design and analysis of microstrip elliptical low pass filter(IEEE Computer Society, 2009) Kumar, P.; Chaturvedi, A.Design and analysis of a stepped impedance elliptical microstrip low pass filter has been described in this paper. To improve the frequency response, fractals have been proposed in the conventional design. Conventional geometry and fractalized geometry have been simulated and thus obtained results are reported and compared.Item Parallel method for discovering frequent itemsets using weighted tree approach(2009) Kumar, P.; Ananthanarayana, V.S.Every element of the transaction in a transaction database may contain the components such as item number, quantity, cost of the item bought and some other relevant information of the customer. Most of the association rules mining algorithms to discover frequent itemsets do not consider the components such as quantity, cost etc. In a large database it is possible that even if the itemset appears in a very few transactions, it may be purchased in a large quantity. Further, this may lead to very high profit. Therefore these components are the most important information and without which it may cause the lose of information. This motivated us to propose a parallel algorithm to discover all frequent itemsets based on the quantity of the item bought in a single scan of the database. This method achieves its efficiency by applying two new ideas. Firstly, transaction database is converted into an abstraction called Weighted Tree that prevents multiple scanning of the database during the mining phase. This data structure is replicated among the parallel nodes. Secondly, for each frequent item assigned to a parallel node, an item tree is constructed and frequent itemsets are mined from this tree based on weighted minimum support. © 2009 IEEE.Item Discovery of weighted association rules mining(2010) Kumar, P.; Ananthanarayana, V.S.Mining of association rules for basket databases, has been investigated by [1] [3] [4], [9], [12], etc. Most of these works focus on mining binary association rules, i.e, most of the association rules mining algorithms to discover frequent itemsets do not consider the quantity in which items have been purchased. This paper discusses an efficient method for discovering a weighted association rules from a large volumes of data in a single scan of the database. The data structure used here is called Weighted Tree. We found that this algorithm is more efficient than Cai's Algorithm. ©2010 IEEE.Item Attribute -TID method for discovering sequence of attributes(2012) Kumar, P.; Ananthanarayana, V.S.The abstraction based algorithms read databases in sequential order and then construct abstraction of the database in memory. Given any database with n attributes, it is possible to read the same in n! ways. These different n! ways lead to abstractions of different sizes. In this paper, for a given a set of transactions D, we find the sequence or order of the attributes in which the database is read, a representation which is compact than PC-tree, can be obtained in the memory. © 2012 Springer-Verlag.Item Geographical location based hierarchical routing strategy for wireless sensor networks(2012) Kumar, P.; Chaturvedi, A.; Kulkarni, M.The overall performance and thus the achievable efficiency of wireless sensor networks (WSNs) rely on the type of protocols deployed to support particular application in hand. In WSN, network's lifetime depends upon the residual energy of individual nodes. In this paper; a brief survey comprises of various reported methodologies that make uses of geographical location attributes for routing in WSN is presented. To assist the routing algorithm on location aspect of the source and destination as well as other intermediate nodes; a location index is formulated based on binary encoded spatial frames. The merit of proposed spatial encoding scheme is its supportiveness on scalability aspects, so it can be easily tailored to accommodate hierarchy based network architectures. Further, the scheme incorporates an effective mechanism to select cluster heads for each cluster in such a way so as to avoid the localization of hot spot effects right from cluster level to network level. © 2012 IEEE.Item An energy efficient algorithm to avoid hot spot effects in Wireless Sensor Networks(IEEE Computer Society help@computer.org, 2013) Kumar, P.; Chaturvedi, A.In this paper, a novel approach is proposed to minimize the hot spot effect to improve the life time of Wireless Sensor Networks (WSNs) based on energy of each sensor node. To implement the proposed approach, the spatial locations of geographical area under surveillance are motioned using binary location index. The simulation work is carried out for two different case studies; in first case the sink/base station is remains stationary during entire observation, whereas in other case the sink is reallocated to appropriate locations at suitable time instants. Timely varying pattern of residual energy of all network nodes and total number of queries supported by entire network till it attains targeted life time is presented and discussed. © 2013 IEEE.Item Life time enhancement of wireless Sensor Network using fuzzy c-means clustering algorithm(Institute of Electrical and Electronics Engineers Inc., 2014) Kumar, P.; Chaturvedi, A.The major issues in wireless Sensor Networks (WSNs) are efficient uses of limited resources and appropriate routing of network paths under severely constrained energy scenarios. To overcome these issues; k-means and fuzzy c-means algorithms are investigated to form clusters and for subsequent selection of cluster heads. For all these clusters; selection of cluster head is done based on member sensor nodes residual energy status (RES) and estimation of Euclidean distances. Depending upon the Euclidean distance measure between the sink node and center of gravity of clusters; these clusters are classified into five types. Further, RES estimations are presented for cluster heads as well simple sensor network nodes. © 2014 IEEE.Item Performance analysis of energy aware routing protocol for Wireless Sensor Networks(Institute of Electrical and Electronics Engineers Inc., 2014) Kumar, P.; Chaturvedi, A.The main issues in wireless Sensor Networks (WSNs) are efficient uses of limited resources and appropriate routing of network path. To overcome these issues multiple sinks are most efficient and effective with proper routing protocols. The residual energy status of entire network nodes of single stationary and multiple sink are compared with number of queries supported and its performances are also evaluated. © 2014 IEEE.