Journal Articles
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Item Hard turning and machine tool: A review(Inderscience Publishers, 2015) Kumar, P.; Chauhan, S.R.; Aggarwal, A.Hard turning is a precise machining operation that imposes strict requirements on both the cutting and machine tools. During the last few decades, the application of hard turning has been increasing in various automotive industrial areas. With the development of new cutting tool, the precision and rigidity of machine tools have been improved to allow hard turning to become a viable process. The objective of this paper is to report a survey of the recent research progress in hard turning with cubic boron nitride tools in regard of machine tool, cutting tool, tool wear, tool geometry and surface issues. This paper report a survey of all the factors that affect the performance of hard turning process, in an attempt to achieve better understanding of hard turning process. A summary of the hard turning techniques is outlined and further a comparison of hard turning and grinding is discussed in brief. © 2015 Inderscience Enterprises Ltd.Item Multifunctional conjugated 1,6-heptadiynes and its derivatives stimulated molecular electronics: Future moletronics(Elsevier Ltd, 2020) Magisetty, R.; Hemanth, N.R.; Kumar, P.; Shukla, A.; Shunmugam, R.; Balasubramanian, B.Over the past decade conducting polymers have been studied for electronic applications, among them, molecular electronics: the study and investigation of molecular building blocks is a next-generation demanded area of research. Hence, the moletronic equivalent multi-functional advantages of cyclopolymerized 1,6-heptadiyne (HD) systems explored in this review. Further, this report elucidates physical properties via conditional cyclopolymerization methodologies, it describes the chemistry of tethering molecular-chains facilitated intrinsic-conductivity. HD and its derivatives induce superior conductivity characteristics via doping elements, wherein, significant electronic conductivity mechanism is attributable to the solitons and anti-solitons, which was described in this context. HD and their derivatives molecular mechanism, its compatibility are expounded for moletronic application, which is new insight of the article. Moreover, required inherent characteristics, for e.g., thermal-stability, chemical-resistance, mechanical properties, magnetic, and electronic properties have been discussed. Furthermore, failures, physical limitations, and its realizable similarity solutions for moletronics have described. Though electronic or moletronic components having failures and other physical limitations, HDs offers excellent conductivity with wide functional and physical properties that could lead to potential candidates to deliver efficient and low-cost moletronic devices. © 2019 Elsevier LtdItem Forest Vulnerability to Climate Change: A Review for Future Research Framework(MDPI, 2022) Roshani; Sajjad, H.; Kumar, P.; Masroor, M.; Rahaman, M.H.; Rehman, S.; Ahmed, R.; Sahana, M.Climate change has caused vulnerability not only to the forest ecosystem but also to forest-dependent communities. Therefore, its management is essential to increase forest ecosystem services and reduce vulnerability to climate change using an integrated approach. Although many scientific studies examined climate change impact on forest ecosystems, forest vulnerability assessment, including forest sensitivity, adaptability, sustainability and effective management was found to be scant in the existing literature. Through a systematic review from 1990 to 2019, this paper examined forest vulnerability to climate change and its management practices. In this paper, descriptive, mechanism and thematic analyses were carried out to analyze the state of existing research, in order to understand the concept of vulnerability arising from climate change and forest management issues. The present study proposed a framework for integrated forest assessment and management for addressing such issues in future research. The conversion of forest land into other land uses, forest fragmentation, forest disturbance and the effects of climate change on the forest ecosystem are the existing problems. Forest vulnerability, effective adaptation to forest ecosystems and long-term sustainability are priority areas for future research. This study also calls for undertaking researchers at a local scale to involve communities for the effective management of forest ecosystems. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.Item Study on soil moisture retention function for the indian forested hillslope soils(Taiwan Geotechnical Society 43, Sec. 4, Keelong Rd, Taipei 106,, 2013) Prasanna, P.; Varija, K.; Kumar, P.Pedotransfer functions (PTFs) are one of the widely used tools to predict the soil water retention curves (SWRC). The objective of this study was to develop and validate point and parametric PTF models based on nonlinear regression technique using the different set of predictors such as particle-size distribution, bulk density, porosity and organic matter content. Soil samples were collected from different elevations at different depths in forested hillslope area of Pavanje river basin that lies in coastal area of Karnataka, India. The point PTF models estimated retention points at 33, 100, 300, 500, 1000, and 1500 kPa pressure heads and the parametric PTF models estimated the van Genuchten and Brooks-Corey retention parameters. The data were evaluated with the root mean square error (RMSE), mean error (ME), and coefficient of determination (R2) between the measured and predicted water contents. The prediction of soil water retention curve using PTFs by point estimation method for the sampled soils was relatively successful (best case R2 = 0.862). Further, a critical comparative analysis on the performances of point and parametric methods was done. It can be suggested to use the developed PTFs for the prediction of soil water retention curve for the loamy sand and sandy loam textured soils in this forest area of the coastal region in south western portion of India.Item Corrosion behaviour of 18%Ni M250 grade maraging steel under welded condition in hydrochloric acid medium(2013) Kumar, P.; Nityananda Shetty, A.N.The corrosion behaviour of welded maraging steel in hydrochloric acid solutions was studied over a range of acid concentration and solution temperature by electrochemical techniques like Tafel extrapolation method and electrochemical impedance spectroscopy. The corrosion rate of welded maraging steel increases with the increase in temperature and concentration of hydrochloric acid in the medium. The energies of activation, enthalpy of activation and entropy of activation for the corrosion process were calculated. The surface morphology of the corroded sample was evaluated by surface examination using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS).Item Electrochemical investigation on the corrosion of 18%Ni M250 grade maraging steel under welded condition in sulfuric acid medium(2013) Kumar, P.; Nityananda Shetty, A.N.The corrosion behavior of welded maraging steel in sulfuric acid solutions has been studied over a range of acid concentrations and solution temperatures by electrochemical techniques such as Tafel extrapolation and electrochemical impedance spectroscopy. The studies have revealed that the corrosion rate of welded maraging steel increases with the increase in temperature and increase in concentration of sulfuric acid in the medium. The thermodynamic parameters such as activation energy, enthalpy of activation and entropy of activation for the corrosion process are calculated. The results obtained through the two techniques are in good agreement. The surface morphology and surface composition of the corroded samples have been examined by scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) analysis, respectively. © 2013 Allerton Press, Inc.Item A geographical location aware energy efficient routing scheme for query based Wireless Sensor Networks(2013) Kumar, P.; Chaturvedi, A.; Shrivastava, S.In this paper, a geographical location based routing scheme is proposed that works effectively for different hierarchical networks and thus supports an important aspect of network scalability. Further, herein a heuristic is proposed that minimizes the occurrence of hot spot to improve the overall life time of Wireless Sensor Networks (WSNs). This utilizes residual energy estimation based on energy of each sensor node. Its implementation mainly comprises of the geographical location of each sensor in Binary Location Index (BLI) representation form, precise updates about the link with shortest path, and coverage of the each sensor; the method which is without change of cluster head is compared with the change of cluster head based on BLI for fixed single sink.Item Corrosion inhibition effect of 2,5-bis (3,4,5-trimethoxy phenyl)-1,3,4-oxadiazole (BTPO) on 18 Ni M250 grade welded maraging steel in 1.0 M sulphuric acid medium(Mohammed Premier University jmaterenvironsci@gmail.com, 2014) Kumar, P.; Nityananda Shetty, A.N.Corrosion inhibition of welded maraging steel in 1.0 M sulphuric acid was studied in the presence of different concentrations of 2,5-bis (3,4,5-trimethoxy phenyl)-1,3,4-oxadiazole (BTPO) by electrochemical techniques. The results confided that BTPO was a good inhibitor, and the inhibition efficiencies obtained from potentiodynamic polarization and electrochemical impedance methods were in good agreement. The inhibitor, BTPO, acted essentially as a mixed-type inhibitor with its inhibition action through its surface adsorption. The inhibition effciency was found to increase with the increase in BTPO concentration but decreased with the increase in temperature. The activation parameters for the corrosion of the alloy and thermodynamic parameters for the adsorption of BTPO on the alloy surface were calculated and discussed. The adsorption of BTPO on welded maraging steel surface was predominantly through physisorption and obeyed the Langmuir adsorption isotherm. Scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDS) study confirmed the formation of an anticorrosion protective film of BTPO on the metal surface.Item Location movement and multiplicity attributes of sink in query-based wireless sensor networks(Inderscience Publishers, 2015) Kumar, P.; Chaturvedi, A.The principal issue in wireless sensor networks (WSNs) is the efficient use of finite energy of each sensor node as it predominantly influences the life time of WSN. In this work, we proposed four case studies on a typical square shape geographical area. In all these cases, the network architecture is hierarchical and same network environment is considered. These cases differ from each other on sink node(s) features viz. single/multiple, optimality of locations and stationary/moveable. As sink node plays an important role in a bridging the communication between the remote entities (sensor nodes) and access points/users; the proposed algorithms are formulated by keeping sink node(s) in centre stage. Further, the paper concludes by comparing various outcome measures like number of queries supported, average residual energy status (RES) estimation that directly impact the 'hot spot' phenomenon, thus enhances network life time while ensuring avoidance of 'islanding' and still adhere to energy efficient usage of network resources. © © 2015 Inderscience Enterprises Ltd.