YMCA University of Science and Technology

About: YMCA University of Science and Technology is a education organization based out in Faridabad, India. It is known for research contribution in the topics: Web page & Web crawler. The organization has 299 authors who have published 568 publications receiving 4547 citations.

An experimental analysis and optimization of machining rate and surface characteristics in wedm of monel-400 using rsm and desirability approach

Abstract: In the present work, an experimental investigation on wire electrical discharge machining (WEDM) of Monel-400 has been presented. Monel-400 is a nickel–copper-based alloy, mostly employed in ships and corrosion-resisting applications. Four input WEDM parameters namely discharge current (Ip), pulse-on time (Ton), pulse-off time (Toff) and servo voltage (SV) have been investigated and modeled for two performance characteristics namely machining rate (MR) and surface roughness (SR). Effect of WEDM parameters has been discussed using response surface graphs. Using analysis of variance, quadratic model is found significant for MR while two factors interaction (2FI) model has been suggested for SR. To optimize multi-performance characteristics, desirability function has been employed. Corresponding to highest desirability, the optimal combination of discharge parameters is Ip: 103 A; Ton: 113 μs; Toff: 37 μs and SV: 50 V. The effect of discharge energy on surface morphology has also been examined. High discharge energy increases the extent of surface damage and results in large size and overlapped craters on machined surface. Low discharge energy and high value of Toff result in minimum defects on machined surface. Trim cutting operations were performed at low discharge energy using different wire offset values. Result shows that surface finish can be improved significantly after a single trim cut irrespective of high discharge energy in rough cut.

Soft computing based multi-objective optimization of Brayton cycle power plant with isothermal heat addition using evolutionary algorithm and decision making

Abstract: Display Omitted Two performance parameters are optimized through NSGA-II and MOEA/D.Optimal values of various input parameters are obtained.Significant improvement (about 15%) in thermal efficiency is reported.Suitability of heat exchanger for a particular application can be found.Effects of various input parameters on dual objectives are reported. An irreversible regenerative Brayton cycle model considering internal and external irreversibilities is developed in matrix laboratory (MATLAB) simulink environment and thermodynamic optimization based on finite time thermodynamic analysis along with multiple criteria is implemented. Evolutionary algorithms based on second version of non-dominated sorting genetic algorithm (NSGA-II) and multi-objective evolutionary algorithm based on decomposition (MOEA/D) are employed to optimize power output and thermal efficiency simultaneously where isobaric-side heat exchanger effectiveness (eH), isothermal-side effectiveness (eH1), sink-side effectiveness (eL), regenerator-side effectiveness (eR), and working medium temperature (T5) are taken as design variables. The optimal values of aforementioned design variables are investigated. Pareto optimal frontiers between dual objectives are obtained and the final optimal values of power output and thermal efficiency are chosen via LINMAP, fuzzy Bellman-Zadeh, Shannon's entropy and TOPSIS decision making approaches. The obtained results are compared and the best one is preferred. An improvement in thermal efficiency from 18.29% to 21.10% is reported. In addition to this, variations of different input parameters on the power output and thermal efficiency are conferred and presented graphically. With the goal of error investigation, the maximum and average errors for the obtained results are designed at last.

Influence of vermicompost application in potting media on growth and flowering of marigold crop

Abstract: This paper reports the influence of vermicomposts prepared from cow dung and house hold waste on the growth and flowering of marigold crop A total of seven potting media were prepared containing soil, cow dung vermicompost and cow dung + house hold waste vermicompost The fertility status of soil and vermicomposts was quantified In these media, growth and flowering of marigold plant seedlings was studied for 60 days The results showed that the vermicomposting process converted the cow dung and household waste into a highly stabilized product having C:N ratio <200 The NPK content of vermicomposts was higher than soil The plant grown in vermicompost-containing potting media had 23 times more plant height than control Results showed that the addition of vermicompost, in appropriate quantities, to potting media has significantly positive effects on growth and flowering of marigold seedlings including plant biomass, plant height, number of buds and flowers It was concluded that addition of vermicompost, in appropriate quantities, to potting media has synergistic effects on growth and yield of marigold

Decision making over the production system life cycle: MOORA method

Abstract: Decisions in robust and flexible production systems are made in an environment often characterized by complexity, need for flexibility, and inclusion of a decision-maker’s subjectivity. Typically in production system life cycle, decisions on the product design, facility location, facility layout, supplier, material, technology, and so forth has to be made in an efficient and timely manner. These decisions are more complex as the decision makers have to assess a wide range of alternatives based on a set of conflicting criteria. In this paper, application of multi-objective optimization on the basis of ratio analysis approach is explored to solve such type of decision making problems. Moreover performance of the reference point approach is also tested for the considered decision making problems.

WEDM of nickel based aerospace alloy: optimization of process parameters and modelling

Abstract: This article presents the experimental data for the machining of Nimonic-90 on wire electrical discharge machining (WEDM). It is a nickel based alloy which possessing creep resistance and high rupture strength at high temperature (up to $$950~^{\circ }\hbox {C}$$ ). Four input process parameters, viz., peak current (Ip), pulse-on time (Ton), pulse-off time (Toff), and servo voltage (SV) were investigated and modelled for three response variables namely cutting speed (CS), surface roughness (SR) and radial overcut (RoC) utilizing Response Surface Methodology (RSM). In present experimentation, quadratic model is suggested for all three responses. Analysis of Variance (ANOVA) indicate that Ip, Ton, Toff and SV are significant process parameters influencing the CS and SR while Ip, Ton and SV were highly significant parameters influencing the RoC. Desirability function was employed to optimize the multi-performance characteristics. Using SEM micrographs and micro-hardness profile, effect of discharge energy (DE) on surface morphology was examined. Topography of machined surface; corresponds to different levels of DE; suggests that high discharge energy results in overlapped and deep craters of large size diameters and high thickness of recast layer whereas low discharge energy results into fine surface with minimum recast layer.