Documents published in Scipedia

• Multi-response optimization of process parameters for TIG welding of Incoloy 800HT by Taguchi grey relational analysis

  A. Srirangan, S. Paulraj

  Collection of Engineering Science and Technology, an International Journal (2017).

  
  

  Abstract

  Incoloy 800HT which was selected as one of the prominent material for fourth generation power plant can exhibit appreciable strength, good resistance to corrosion and oxidation in high temperature environment. This study focuses on the multi-objective optimization using grey relational analysis for Incoloy 800HT welded with tungsten inert arc welding process with N82 filler wire of diameter 1.2 mm. The welding input parameters play a vital role in determining desired weld quality. The experiments were conducted according to L9 orthogonal array. The input parameter chosen were the welding current, Voltage and welding speed. The output response for quality targets chosen were the ultimate tensile strength and yield strength (at room temperature, 750 °C) and impact toughness. Grey relational analysis was applied to optimize the input parameters simultaneously considering multiple output variables. The optimal parameters combination was determined as A2 B1 C2 i.e. welding current at 110 A, voltage at 10 V and welding speed at 1.5 mm/s. ANOVA method was used to assess the significance of factors on the overall quality of the weldment. The output of the mechanical properties for best and least grey relational grade was validated by the metallurgical characteristics:

  Abstract
  Incoloy 800HT which was selected as one of the prominent material for fourth generation power plant can exhibit appreciable strength, good resistance to corrosion and oxidation [...]

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• Shadow removal using sparse representation over local dictionaries

  R. Sasi, V. Govindan

  Collection of Engineering Science and Technology, an International Journal (2017).

  
  

  Abstract

  The presence of shadow in an image is a major problem associated with various visual processing applications such as object recognition, traffic surveillance and segmentation. In this paper, we introduce a method to remove the shadow from a real image using the morphological diversities of shadows and sparse representation. The proposed approach first generates an invariant image and further processing is applied to the invariant image. Here, shadow removal is formulated as a decomposition problem that uses separate local dictionaries for shadow and nonshadow parts, without using single global or fixed generic dictionary. These local dictionaries are constructed from the patches extracted from the residual of the image obtained after invariant image formation. Finally, non-iterative Morphological Component Analysis-based image decomposition using local dictionaries is performed to add the geometric component to the non-shadow part of the image so as to obtain shadow free version of the input image. The proposed approach of shadow removal works well for indoor and outdoor images, and the performance has been compared with previous methods and found to be better in terms of RMSE.

  Abstract
  The presence of shadow in an image is a major problem associated with various visual processing applications such as object recognition, traffic surveillance and segmentation. [...]

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• Design of optimal input–output scaling factors based fuzzy PSS using bat algorithm

  D. Sambariya, R. Gupta, R. Prasad

  Collection of Engineering Science and Technology, an International Journal (2017).

  
  

  Abstract

  In this article, a fuzzy logic based power system stabilizer (FPSS) is designed by tuning its input–output scaling factors. Two input signals to FPSS are considered as change of speed and change in power, and the output signal is considered as a correcting voltage signal. The normalizing factors of these signals are considered as the optimization problem with minimization of integral of square error in single-machine and multi-machine power systems. These factors are optimally determined with bat algorithm (BA) and considered as scaling factors of FPSS. The performance of power system with such a designed BA based FPSS (BA-FPSS) is compared to that of response with FPSS, Harmony Search Algorithm based FPSS (HSA-FPSS) and Particle Swarm Optimization based FPSS (PSO-FPSS). The systems considered are single-machine connected to infinite-bus, two-area 4-machine 10-bus and IEEE New England 10-machine 39-bus power systems for evaluating the performance of BA-FPSS. The comparison is carried out in terms of the integral of time-weighted absolute error (ITAE), integral of absolute error (IAE) and integral of square error (ISE) of speed response for systems with FPSS, HSA-FPSS and BA-FPSS. The superior performance of systems with BA-FPSS is established considering eight plant conditions of each system, which represents the wide range of operating conditions.

  Abstract
  In this article, a fuzzy logic based power system stabilizer (FPSS) is designed by tuning its input–output scaling factors. Two input signals to FPSS are considered as change [...]

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• Analysis of heatlines and entropy generation during double-diffusive MHD natural convection within a tilted sinusoidal corrugated porous enclosure

  S. Hussain

  Collection of Engineering Science and Technology, an International Journal (2017).

  
  

  Abstract

  The natural convection and entropy generation during double-diffusive MHD natural convection in a tilted sinusoidal corrugated porous enclosure is investigated numerically in this work by using heatline visualization technique. The top and bottom horizontal walls are assumed as adiabatic and non-diffusive, while the left and right vertical corrugated sidewalls are maintained at a constant hot and cold temperatures and concentrations respectively. The flow in the enclosure is subjected to an inclined magnetic field. The enclosure is filled with an electrically conducting fluid [Pr = 0.024] saturated with a porous media. The numerical computations are presented for various values of Rayleigh number (Ra), Hartmann number (Ha), Lewis number (Le), Darcy number (Da), buoyancy ratio (N), magnetic field orientation angle (φ) and enclosure inclination angle (Φ). In addition, the entropy generation due to fluid friction, thermal gradients, diffusion, and magnetic field beside the total entropy generation are studied and discussed. It is found that the flow circulation decreases strongly when the magnetic field applied horizontally and the enclosure is considered vertical. Heatline visualization concept is successfully applied to the considered problem. The average Nusselt number decreases when the Lewis number increases, while the average Sherwood number increases when the Lewis number increases. Also, both average Nusselt and Sherwood numbers increase when the Darcy number and buoyancy ratio increase. Moreover, the results show that the entropy generations due to magnetic field when the enclosure is subjected to the horizontal magnetic field are higher than the corresponding values when it subjected to the vertical magnetic field.

  Abstract
  The natural convection and entropy generation during double-diffusive MHD natural convection in a tilted sinusoidal corrugated porous enclosure is investigated numerically [...]

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• Magneto-dielectric properties of doped ferrite based nanosized ceramics over very high frequency range

  A. Saini, P. Kumar, B. Ravelo, S. Lallechere, A. Thakur, P. Thakur

  Collection of Engineering Science and Technology, an International Journal (2017).

  
  

  Abstract

  In the present study, indium doped nano sized nickel zinc cobalt based ferrite ceramics with composition Ni0.5 Zn0.3 Co0.2 Inx Fe2-x O4 (x = 0.2 and 0.4) were synthesized by a co-precipitation technique. Powdered sample has been pre-sintered at 800 °C, pressed into toroids and finally sintered at 1000 °C. The single phase formation of the presintered powder has been confirmed by X ray diffraction (XRD). The average particle size of the presintered powder has been estimated by field emission scanning electron microscope (FESEM) and found to be about ~60 nm for x = 0.2 and ~80 nm at x = 0.4. The electromagnetic characterization has been made using vector network analyzer. High value of permeability (17.3 and 15.2 for x = 0.2 and 0.4 respectively) with low magnetic loss tangent of 10−1 order were obtained. Permittivity of 8.2 and 10, and dielectric loss tangent of the order of 10−2 were also achieved. With the measured electromagnetic parameters, miniaturization factor of 12.32 and normalized characteristic impedance close to unity (1.23) were obtained up to 100 MHz frequency. These fascinating parameters definitely propose Ni0.5 Zn0.3 Co0.2 In0.4 Fe1.6 O4 ceramics as a substrate material for miniaturized antenna in very high frequency band. Possible reasons and mechanisms of electromagnetic properties for different concentrations of indium are discussed in the paper.

  Abstract
  In the present study, indium doped nano sized nickel zinc cobalt based ferrite ceramics with composition Ni0.5 Zn0.3 Co0.2 Inx Fe2-x O4 (x = 0.2 and 0.4) were synthesized [...]

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• Evaluation of in-cylinder mixture homogeneity in a diesel HCCI engine – A CFD analysis

  N. Ramesh, J. Mallikarjuna

  Collection of Engineering Science and Technology, an International Journal (2017).

  
  

  Abstract

  Performance and emission characteristics of HCCI engines depend on achieving a good in-cylinder homogeneous mixture. The formation of in-cylinder mixture depends on many engine parameters, which need optimization. In addition, as of now, there is no direct way to clearly describe and estimate in-cylinder mixture homogeneity. In the CFD analysis, it is evaluated indirectly using contour plots of equivalence ratio, variation of in-cylinder pressure with crank angles, heat release curves or by the comparison of emissions. In this study, an attempt has been made to develop methods to evaluate the in-cylinder mixture homogeneity by the CFD analysis using AVL-FIRE. Here, global and local in-cylinder fuel distribution and in-cylinder fuel distribution index are used to evaluate the mixture homogeneity. In order to evaluate these methods, mixture homogeneities in two cases of fuel injections with 7- and 10-hole injector are compared. Finally, we found that the global fuel distribution (GFD) plot helps direct quantitative assessment of mixture distribution in various ER range. However, the GFD method cannot explain the spatial variation of fuel distribution and does not provide mixture homogeneity on a simple scale. In the method of plotting fuel distribution index, the overall homogeneity will be evaluated on a scale of 0 to 1 by a simple way. In the method of plotting local fuel distribution (LFD), the spatial variation of mixture homogeneity is well defined in local zones both in radial and axial directions. Further, these proposed methods help us to reduce the computation time significantly.

  Abstract
  Performance and emission characteristics of HCCI engines depend on achieving a good in-cylinder homogeneous mixture. The formation of in-cylinder mixture depends on many engine [...]

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• Microcontroller USB interfacing with MATLAB GUI for low cost medical ultrasound scanners

  J. Raj, S. Rahman, S. Anand

  Collection of Engineering Science and Technology, an International Journal (2017).

  
  

  Abstract

  This paper presents an 8051 microcontroller-based control of ultrasound scanner prototype hardware from a host laptop MATLAB GUI. The hardware control of many instruments is carried out by microcontrollers. These microcontrollers are in turn controlled from a GUI residing in a computing machine that is connected over the USB interface. Conventionally such GUIs are developed using ‘C’ language or its variants. But MATLAB GUI is a better tool, when such GUI programs need to do huge image/video processing. However interfacing MATLAB with the microcontroller is a challenging task. Here, MATLAB interfacing through an intermediate MEX ‘C’ language program is presented. This paper outlines the MEX programming methods for achieving the smooth interfacing of microcontrollers with MATLAB GUI.

  Abstract
  This paper presents an 8051 microcontroller-based control of ultrasound scanner prototype hardware from a host laptop MATLAB GUI. The hardware control of many instruments [...]

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• Effects of induced magnetic field and homogeneous–heterogeneous reactions on stagnation flow of a Casson fluid

  C. Raju, N. Sandeep, S. Saleem

  Collection of Engineering Science and Technology, an International Journal (2017).

  
  

  Abstract

  In this study, we analyzed the induced magnetic field effect on the stagnation-point flow of a non-Newtonian fluid over a stretching sheet with homogeneous–heterogeneous reactions and non-uniform heat source or sink. The transformed ordinary differential equations are solved numerically using Runge–Kutta and Newtons method. For physical relevance we analyzed the behavior of homogeneous and heterogeneous profiles individually in the presence of induced magnetic field. The effects of different non-dimensional governing parameters on velocity, induced magnetic field, temperature and concentration profiles, along with the skin friction coefficient and local Nusselt number, are discussed and presented through graphs. The results of the present study are validated by comparing with the existed literature. Results indicate that induced magnetic field parameter and stretching ratio parameter have the tendency to enhance the heat transfer rate.

  Abstract
  In this study, we analyzed the induced magnetic field effect on the stagnation-point flow of a non-Newtonian fluid over a stretching sheet with homogeneous–heterogeneous [...]

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• Bat algorithm optimized fuzzy PD based speed controller for brushless direct current motor

  K. Premkumar, B. Manikandan

  Collection of Engineering Science and Technology, an International Journal (2017).

  
  

  Abstract

  In this paper, design of fuzzy proportional derivative controller and fuzzy proportional derivative integral controller for speed control of brushless direct current drive has been presented. Optimization of the above controllers design is carried out using nature inspired optimization algorithms such as particle swarm, cuckoo search, and bat algorithms. Time domain specifications such as overshoot, undershoot, settling time, recovery time, and steady state error and performance indices such as root mean squared error, integral of absolute error, integral of time multiplied absolute error and integral of squared error are measured and compared for the above controllers under different operating conditions such as varying set speed and load disturbance conditions. The precise investigation through simulation is performed using simulink toolbox. From the simulation test results, it is evident that bat optimized fuzzy proportional derivative controller has superior performance than the other controllers considered. Experimental test results have also been taken and analyzed for the optimal controller identified through simulation.

  Abstract
  In this paper, design of fuzzy proportional derivative controller and fuzzy proportional derivative integral controller for speed control of brushless direct current drive [...]

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• Investigation on energy efficient sensor node placement in railway systems

  A. Philipose, R. A

  Collection of Engineering Science and Technology, an International Journal (2017).

  
  

  Abstract

  Recently wireless sensor network (WSN) has been widely used for monitoring railway tracks and rail tunnels. The key requirement in the design of such WSN is to minimize the energy consumption so as to maximize the network lifetime. This paper includes the performance of an improved medium access control (MAC) protocol, namely, time adaptive-bit map assisted (TA-BMA) protocol, for the purpose of communication between the sensors placed in a railway wagon. The train is considered to be moving at a constant speed, and the sensor nodes are stationary with respect to the motion of train. The effect of mobility on the proposed MAC protocol is determined using genetic algorithm (GA), and the observed increase in energy consumption on considering mobility is 18.51%. Performance analysis of the system model is carried out using QualNet (ver. 7.1), and the energy consumption in transmit mode, receive mode, percentage of time in sleep mode, end-to-end delay and throughput are investigated.

  Abstract
  Recently wireless sensor network (WSN) has been widely used for monitoring railway tracks and rail tunnels. The key requirement in the design of such WSN is to minimize the [...]

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