Motilal Nehru National Institute of Technology Allahabad

About: Motilal Nehru National Institute of Technology Allahabad is a education organization based out in Allahabad, Uttar Pradesh, India. It is known for research contribution in the topics: Computer science & Control theory. The organization has 2475 authors who have published 5067 publications receiving 61891 citations. The organization is also known as: NIT Allahabad & Motilal Nehru Regional Engineering College.

Methods for solving singular boundary value problems using splines: a review

Abstract: This paper surveys and reviews papers of spline solution of singular boundary value problems. Among a number of numerical methods used to solve two-point singular boundary value problems, spline methods provide an efficient tool. Techniques collected in this paper include cubic splines, non-polynomial splines, parametric splines, B-splines and TAGE method.

GLCM and its application in pattern recognition

Abstract: Grey Level Co-Occurrence matrix is one of the oldest techniques used for texture analysis. The Grey Level Co-Occurrence matrix has two important parameters i.e. distance and direction. In this paper various combinations of distance and directional angles used for GLCM calculation are analyzed in order to recognize certain patterned images based on their textural features. Patterns considered in this paper are horizontally striped, vertically striped, right diagonally striped, left diagonally striped, checkered and irregular. Our proposed method has achieved a percentage accuracy of 96, 98, 96, 90, 96 and 94 for horizontally striped, vertically striped, right diagonally striped, left diagonally striped, checkered and irregular patterns respectively. Thus an overall percentage accuracy of 95 is achieved for pattern recognition using GLCM.

Quality Improvement by Parameter Optimization in Laser Trepan Drilling of Superalloy Sheet

Abstract: Drilling of small-diameter holes meeting stringent quality standards in superalloys such as Inconel718 (having widespread applications in aeroengine component manufacturing) has always been a challenging task. Laser drilling has wide applications in the aerospace industry. Laser trepan drilling (LTD) provides better control over the drilled hole geometry compared with laser percussion drilling to fulfill the higher dimensional accuracy requirement. This article presents an integrated approach of artificial neural network and genetic algorithm for the modeling and optimization of geometrical quality characteristics such as hole taper and circularity during LTD of 1.6 mm thick Inconel718 superalloy sheet. The optimum results show considerable improvements in hole taper, and hole circularities at laser beam entry and exit sides. Higher values of laser pulse frequency and trepanning speed in the present range have resulted in more circular holes with reduced taper.

Capture and chemical fixation of carbon dioxide by chitosan grafted multi-walled carbon nanotubes

Abstract: Since last few years, climate change has been a serious concern all over the world. The concentrations of carbon dioxide (CO2) in the atmosphere have been increasing at an alarming rate and this has been a key contributor to global warming and associated climate change. Hence, there is a global demand to reduce atmospheric CO2 for balancing our climatic condition. Herein, we have synthesized cost-effective and environment-friendly chitosan grafted multi-walled carbon nanotubes (CSMWCNTs) based solid adsorbents for the capture of carbon dioxide as well as an efficient catalyst for its chemical fixation. Physical characterization of CSMWCNTs was done by fourier transformation infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscope (SEM) analysis, Brunauer-Emmett-Teller (BET) isotherm and thermogravimetric analysis (TGA). The CO2 uptake capacity of CSMWCNTs was found to be significantly higher (1.92 ccg−1) than that of pure chitosan but lower than functionalized multi-walled carbon nanotubes (10.20 ccg−1). Moreover, it has been found that CSMWCNTs shows significant catalytic activity towards the chemical fixation of CO2 with epoxides (propylene oxide and styrene oxide) and leading to the formation of corresponding cyclic carbonates. Cycloaddition of CO2 with epoxides is one of the greenest approach to form high value added organic chemicals which have several applications as synthons in fine chemicals, petrochemicals, valuable intermediates, antifoam additives, engineering plastics and pharmaceuticals. Hence, to the best of our knowledge, for the first time capture and chemical fixation of CO2 (at atmospheric pressure) by CSMWCNTs is being reported herein and which may help to reduce CO2 gas from the atmosphere.

Computer-aided genetic algorithm based multi-objective optimization of laser trepan drilling

Abstract: The laser trepan drilling (LTD) has proven to produce better quality holes in advanced materials as compared with laser percussion drilling (LPD). But due to thermal nature of LTD process, it is rarely possible to completely remove the undesirable effects such as recast layer, heat affected zone and micro cracks. In order to improve the hole quality, these effects are required to be minimized. This research paper presents a computer-aided genetic algorithm-based multi-objective optimization (CGAMO) methodology for simultaneous optimization of multiple quality characteristics. The optimization results of the software CGAMO has been tested and validated by the published literature. Further, CGAMO has been used to simultaneously optimize the recast layer thickness (RLT) at entrance and exit in LTD of nickel based superalloy sheet. The predicted results show minimization of 99.82% and 85.06% in RLT at entrance and exit, respectively. The effect of significant process parameters on RLT has also been discussed.