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Number of results: 39
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Abstract

Artificial neural network (ANN), a Computational tool that is frequently applied in the modeling and simulation of manufacturing processes. The emerging forming technique of sheet metal which is typically called single point incremental forming (SPIF) comes into the map and the research interest towards its technological parameters. The surface quality of the end product is a major issue in SPIF, which is more critical with the hard metals. The part of the brass metal is demanded in many industrial uses because of its high load-carrying capacity and its wear resistance property. Considering the industrial interest and demand of the brass metal products, the present study is done with the SPIF experiment on calamine brass Cu67Zn33 followed by an ANN analysis for predicting the absolute surface roughness. The modeling result shows a close agreement with the measured data. The minimum and maximum errors are found in experiment 3 and experiment 7 respectively. The error of predicted roughness is found in the range of –30.87 to 20.23 and the overall coefficient of performance of ANN modeling is 0.947 which is quite acceptable.
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Authors and Affiliations

Manish Oraon
1
Vinay Sharma
1

  1. Birla Institute of Technology, Faculty of Production Engineering, India
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Abstract

This research paper discusses an analytical approach to designing the active region of light emitting diodes to enhance its performance. The layers in the active region were modified and the effects of changing the width of quantum well and barrier layers in a multi-quantum light emitting diode on the output power and efficiency have been investigated. Also, the ratio of the quantum well width to the B layer width was calculated and proposed in this research paper. The study is carried out on two different LED structures. In the first case, the width of the quantum well layers is kept constant while the width of the B layers is varied. In the second case, both the quantum well and B layer widths are varied. Based on the simulation results, it has been observed that the LED power efficiency increases considerably for a given quantum well to B layers width ratio without increasing the production complexity. It is also seen that for a desired power efficiency the width of quantum well should be between 0.003 µm and 0.006 µm, and the range of B width (height) should be 2.2 to 6 times the quantum well width. The proposed study is carried out on the GaN-AlGaN-based multi-quantum well LED structure, but this study can be extended to multiple combinations of the semiconductor structures.
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Bibliography

  1. Lenk, R. & Lenk, C. Practical Lighting Design with LEDs. (2nd. ed.) (John Wiley & Sons, Ltd., 2017).
  2. , S. M. & Kwok, K. Ng, Physics of Semiconductor Devices. (4th ed.) (Wiley-Interscience, 2006).
  3. Van Zeghbroeck, B. Principles Of Semiconductor Devices. (Prentice-Hall, 2006).
  4. Schulte-Römer, N., Meier, J., Söding, M. & Dannemann, E. The LED paradox: how light pollution challenges experts to reconsider sustainable lighting. Sustainability 11, 6160 (2019). https://doi.org/10.3390/su11216160
  5. Sharma, L, & Sharma, R. Optimized design of narrow spectral linewidth nonpolar m-plane InGaN/GaN micro-scale light-emitting diode. J. Opt. 49, 397–402 (2020). https://doi.org/10.1007/s12596-020-00632-4
  6. Rashidi, A. et al. High-speed nonpolar InGaN/GaN LEDs for visible-light communication. IEEE Photonics Technol. Lett. 29, 381–384 (2017). https://doi.org/10.1109/LPT.2017.2650681
  7. Shi, J. et al. III-Nitride-based cyan light-emitting diodes with GHz bandwidth for high-speed visible light communicatio. IEEE Electron. Device Lett. 37, 894–897 (2016). https://doi.org/10.1109/LED.2016.2573265
  8. Gong, M. et al. Semi-polar (20–21) InGaN/GaN multiple quantum wells grown on patterned sapphire substrate with internal quantum efficiency up to 52 percent. Appl. Phys. Express. 13, 091002 (2020). https://doi.org/10.35848/1882-0786/abac91
  9. Rouet-Leduc, B., Barros, K., Lookman, T. & Humphreys, C. J. Optimisation of GaN LEDs and the reduction of efficiency droop using active machine learning. Sci. Rep. 6, 24862 (2016). https://doi.org/10.1038/srep24862
  10. Piprek, J. Simulation-based machine learning for optoelectronic device design: perspectives, problems, and prospects. Opt. Quantum Electron. 53, 175 (2021). https://doi.org/10.1007/s11082-021-02837-8
  11. Usman, M., Munsif, M. & Abdur-Rehman, A., High internal quantum efficiency of green GaN-based light-emitting diodes by thickness-graded last well/last B and composition-graded electron blocking layer Opt. Quantum Electron. 52, 320 (2020). https://doi.org/10.1007/s11082-020-02436-z
  12. Song, K., Mohseni, M. & Taghipour, F. Application of ultraviolet light-emitting diodes (UV-LEDs) for water disinfection. Water Res. 94, 341–349 (2016). https://doi.org/10.1016/j.watres.2016.03.003
  13. Liao, Ch.-L. et al. High-speed GaN-based blue light-emitting diodes with gallium-doped ZnO current spreading layer. IEEE Electron. Device Lett. 34, 611–613 (2013). https://doi.org/10.1109/LED.2013.2252457
  14. Quan, Z. et al. High bandwidth freestanding semipolar (11–22) InGaN/GaN light-emitting diodes. IEEE Photon. J. 8, (2016). https://doi.org/10.1109/JPHOT.2016.2596245
  15. Shi, J.-W. et al. III-nitride-based cyan light-emitting diodes with GHz bandwidth for high-speed visible light communication. IEEE Electron. Device Lett. 37, 894–897 (2016). https://doi.org/10.1109/LED.2016.2573265
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Authors and Affiliations

Lokesh Sharma
1
Ritu Sharma
1

  1. Department of Electronics and Communication Engineering, Malaviya, National Institute of Technology, Jaipur, Rajasthan 302017, India
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Abstract

Objectives: To design and simulate a buck converter and detector circuit which can prognostically indicate the power supply failure. Failure of Aluminium Electrolytic Capacitor (AEC) is considered as the parameter causing the power supply failure. To analyse variation of output ripple voltage due to possible changes in the Equivalent Series Resistance (ESR) and effective capacitance of the capacitor and design a detector to detect the failure of power supply prognostically.
Methods: A DC-DC buck converter in SMPS topology is designed by assuming an input voltage of 12V with 3 volts possible fluctuations and an output voltage of 3.3 volts is desired. Simulation is carried out to measure the variation in output ripple voltage caused due to aging of electrolytic capacitor using TINA by Texas Instruments. A detector is also designed to compare the ripple voltage and a predefined threshold voltage so as to indicate the possible failure of Switched Mode Power Supply (SMPS) well in advance by monitoring the output ripple increase.
Novelty: Having a fault tolerant power supply is very important in safety critical applications. Here by monitoring the output ripple variation, the degradation of AEC is predicted by calculating the ESR and capacitance variation. This simple yet effective prognostic detection will support in the design of fault tolerant power supplies.
Highlight: It is found that, the ripple at the output increases with aging of the electrolytic capacitor, as with time the equivalent capacitance decreases and Equivalent Series Resistance (ESR) of the capacitor increases. The designed detector output is found to prognostically indicate the failure of SMPS.
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Authors and Affiliations

Preethi Sharma K
1
T. Vijayakumar
1

  1. Department of ECE, SJB Institute of Technology, Bengaluru, India
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Abstract

This paper proposes a generalized fractional controller for integer order systems with time delay. The fractional controller structure is so adopted to have a combined effect of fractional filter and Smith predictor. Interestingly, the resulting novel controller can be decomposed into fractional filter cascaded with an integer order PID controller. The method is applied to two practical examples i.e. liquid level system and Shell control fractionator system. The closed- loop responses resulting from the proposed method are compared with that of the available methods in the literature. For quantitative evaluations of the proposed method, Integral Absolute Error (IAE) and Integral Square Control Input (ISCI) performance criteria are employed. The proposed method effectively enhances the closed-loop response by improving the IAE values, reducing the control effort inputs to achieve the desired output. The disturbance rejection and robustness tests are also carried out. The robustness test reveals a significant improvement in the maximum absolute sensitivity measure. That is displayed in numerical simulations of the paper.

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Authors and Affiliations

Shaival Hemant Nagarsheth
Shambhu Nath Sharma
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Abstract

Improvement in the exegetic efficiency of a solar air heater (SAH) can be done by enhancing the rate of heat transfer. In this work, the exergetic efficiency optimization of an artificially roughened solar air heater having an inverted L-shape rib has been performed. The numerical analysis of the exergetic performance of the solar air heater was carried out at a constant heat flux of 1000 W/m2. The study was conducted to investigate the effect of different relative roughness pitch (7.14–17.86) on the exergy losses, under the Reynolds number range of 3000 to 18 000. The roughness parameter of this geometry has been optimized and found to be among functional operating parameters like average solar intensity and temperature rise across the collector. The optimized value of relative roughness pitch is 17.86 at the isolation of 1000 W/m 2, and the parameter of temperature rise ranges from 0.005 to 0.04.
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Authors and Affiliations

Manmohan Chaudhari
1
Sohan Lal Sharma
2
Ajoy Debbarma
2

  1. Maya Institute of Technology and Management, Selaqui, Dehradun, Uttarakhand-248007, India
  2. National Institute of Technology, Hamirpur, Himachal Pradesh, 177005, India
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Abstract

Physical machine systems are represented in the form of differential equations. These differential equations may be of the higher order and difficult to analyses. Therefore, it is necessary to convert the higher-order to lower order which replicates approximately similar properties of the higher-order system (HOS). This article presents a novel approach to reducing the higher-order model. The approach is based on the hunting demeanor of the hawk and escaping of the prey. The proposed method unifies the Harris hawk algorithm and the moment matching technique. The method is applied on single input single output (SISO), multi-input multi-output (MIMO) linear time–invariant (LTI) systems. The proposed method is justified by examining the result. The results are compared using the step response characteristics and response error indices. The response indices are integral square error, integral absolute error, integral time absolute error. The step response characteristics such as rise time, peak, peak time, settling time of the proposed reduced order follows 97%–100% of the original system characteristics.
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Authors and Affiliations

Aswant Kumar Sharma
1
Dhanesh Kumar Sambariya
1

  1. Department of Electrical Engineering, Rajasthan Technical University, Rawath Bhata Road 324010, Kota, India
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Abstract

The evolution of microstructured optical fibers with hexagonal array (H-MOFs) of air-holes rooted in the background of undoped silica has led to the realization of an ideal host for encouraging and technologically entitled optical properties. We focus to explore the divergence of radiation into free space from the end-facet of solid-core H-MOFs by using the improved theoretical model. Also, we investigated the wavelength dependence of beam divergence angle for principal core mode of H-MOFs under step-index fiber approximation (SIFA). Experimental results have been included for comparison.

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Authors and Affiliations

D.K. Sharma
S.M. Tripathi
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Abstract

In this paper, a low power highly sensitive Triple Metal Surrounding Gate (TM-SG) Nanowire MOSFET photosensor is proposed which uses triple metal gates for controlling short channel effects and III–V compound as the channel material for effective photonic absorption. Most of the conventional FET based photosensors that are available use threshold voltage as the parameter for sensitivity comparison but in this proposed sensor on being exposed to light there is a substantial increase in conductance of the GaAs channel underneath and, thereby change in the subthreshold current under exposure is used as a sensitivity parameter (i.e., Iillumination/IDark). In order to further enhance the device performance it is coated with a shell of AlxGa1-xAs which effectively passivates the GaAs surface and provides a better carrier confinement at the interface results in an increased photoabsorption. At last performance parameters of TM-SG Bare GaAs Nanowire MOSFET are compared with TM-SG core-shell GaAs/AlGaAs Nanowire MOSFET and the results show that Core-Shell structures can be a better choice for photodetection in visible region.

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Authors and Affiliations

S.K. Sharma
A. Jain
B. Raj
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Abstract

Background: a humidity sensor is used to sense and measure the relative humidity of air. A new composite system has been fabricated using environmental pollutants such as carbon black and low-cost zinc oxide, and it acts as a humidity sensor. Residual life of the sensor is calculated and an expert system is modelled. For properties and nature confirmation, characterization is performed, and a sensing material is fabricated. Methodology: characterization is performed on the fabricated material. Complex impedance spectroscopy (CIS), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) are all used to confirm the surface roughness, its composite nature as well as the morphology of the composite. The residual lifetime of the fabricated humidity sensor is calculated by means of accelerated life testing. An intelligent model is designed using artificial intelligence techniques, including the artificial neural network (ANN), fuzzy inference system (FIS) and adaptive neuro-fuzzy inference system (ANFIS). Results: maximum conductivity obtained is 6.4×10⁻³ S/cm when zinc oxide is doped with 80% of carbon black. Conclusion: the solid composite obtained possesses good humidity-sensing capability in the range of 30–95%. ANFIS exhibits the maximum prediction accuracy, with an error rate of just 1.1%.

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Authors and Affiliations

C. Bhargava
J. Aggarwal
P.K. Sharma
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Abstract

The present work aims at studying the effects of orientation, size, position, and the combination of multiple internal diathermal obstructions in a fluid-saturated square porous enclosure, generally encountered in thermal insulations. The overall objective is to suppress the natural convection fluid flow and heat transfer across a differentially heated porous enclosure. To serve this purpose, multiple diathermal obstructions are employed to mechanically protrude into a porous medium. It is sought to estimate the effect of various types of orientation, clustering and alternate positioning of obstructions by considering number of obstructions (Np), length of obstructions (λ), modified Rayleigh number (Ra*) on local and average Nusselt number (Nu). The Darcy model for porous media is solved using Finite difference method along with Successive Accelerated Replacement scheme. One of the findings is that the value of the Nusselt number decreases by increasing both, the number of obstructions as well as the length of obstructions irrespective of its orientation and positioning. The reduction in Nusselt number is significant with obstructions attached on lower half of the hot wall and/or on upper half of cold wall. In addition, the overall reduction in Nusselt number is slightly greater with obstructions attached explicitly to the cold wall.

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Authors and Affiliations

Jayesh Subhash Chordiya
Ram Vinoy Sharma
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Abstract

This paper proposes an active noise control (ANC) application to attenuate siren noise for the patient lying inside ambulance with no sound proofing. From the point of cost effectiveness, a local ANC system based on feedforward scheme is considered. Further, to handle the limitation of limited Zone of Silence (ZoS), the ANC based on virtual sensing is explored. The simulations are done in MATLAB for the recorded ambulance siren noise signal. The results indicate that ANC can be an effective solution for creating a silent environment for the patient.
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Authors and Affiliations

Sharma Manoj Kumar
Vig Renu
Pal Ravi
Shantharam Veena
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Abstract

The paper projects the potential of agricultural waste Saraca indica leaf powder (SILP) in biosorbing chromium from aqueous system. The influence of pH, contact time, metal concentration, biomass dosage and particle size on the selectivity of the removal process was investigated. The maximum sorption efficiency of SILP for Cr(lll): 85.23% and Cr(VI): 89.67%was found to be pH dependent giving optimum sorption at pH 6.5 and 2.5 respectively. The adsorption process fitted well to both Freundlich and Langmuir isotherms. Morphological changes observed in Scanning Electron Micrographs ofmetal treated biomass confirm the existence of biosorption phenomenon. Fourier Transform Infra-red Spectrometry confirms that amino acid-Cr interactions contribute a significant role in the biosorption of chromium using target leafpowder. The successful applications of easily abundant agricultural waste SILP, as a biosorbent have potential for a low technological pretreatment step, prior to economically not viable high-tech chemical treatments for the removal of Cr from water bodies.
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Authors and Affiliations

Pritee Goyal
Parul Sharma
Shalini Srivastava
M.M. Srivastava
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Abstract

In this paper, a novel double-layer multiband circularly polarized microstrip patch antenna is proposed. The design employs the concept of slotted patch fed with proximity coupled feed having defected ground plane (DGS). The proposed antenna achieves multiple operating frequency bands including FB1 (11.15 GHz), FB2 (4.17 GHz), FB3 (4.87 GHz) and FB4 (1.98 GHz). The proposed antenna has obtained bandwidth of 12.98%, 4.7%, 4.69% and 5.39% at FB1, FB2, FB3 and FB4 bands, respectively. The proposed antenna also exhibits circular polarization in the frequency band FB4. The 3dB ARBW of the antenna is 9.23% at 11.2 GHz. Finally, a metallic cavity is used with the antenna to achieve a unidirectional radiation pattern. The designed antenna radiation characteristics are verified with the experimental results.

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Authors and Affiliations

Ashish Kumar Singh
Ankit Sharma
M. Lakshmanan
Deepak Gangwar
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Abstract

Heat exchangers are widely employed in numerous industrial applications to serve the heat recovery and cooling purpose. This work reports a performance analysis of a tube in tube heat exchanger for different flow configuration under variable operating conditions. The experimental investigation was performed on a U-shaped double pipe heat exchanger set up whereas Commercial Computational Fluid Dynamics code FLUENT along with k-ε turbulence modeling scheme was implemented for the simulation study. The flow solution was achieved by implementing k-ε turbulence modeling scheme and the simulation findings were compared with the experimental results. The experimental findings were in good agreement with the simulation results. The counter-flow configuration was found to be 29.4% more effective than the co-current one at low fluid flow rate. Direct relationship between heat transfer rate and flow rate is observed while effectiveness and LMTD showed inverse relationship with it. The significance of inlet temperature of hot and cold stream has been evaluated, they play crucial role in heat exchange process.

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Authors and Affiliations

Vikas Kannojiya
Rahul Gaur
Pushpender Yadav
Riya Sharma

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