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Article
Publication date: 14 February 2022

Rohit Gupta, Indranil Biswas, B.K. Mohanty and Sushil Kumar

In the paper, the authors study the simultaneous influence of incentive compatibility and individual rationality (IR) on a multi-echelon supply chain (SC) under uncertainty. The…

272

Abstract

Purpose

In the paper, the authors study the simultaneous influence of incentive compatibility and individual rationality (IR) on a multi-echelon supply chain (SC) under uncertainty. The authors study the impact of contract sequence on coordination strategies of a serial three-echelon SC consisting of a supplier, a manufacturer and a retailer in an uncertain environment.

Design/methodology/approach

The authors develop a game-theoretic framework of a serial decentralized three-echelon SC. Under a decentralized setting, the supplier and the manufacturer can choose from two contract types namely, wholesale price (WP) and linear two-part tariff (LTT) and it leads to four different cases of contract sequence.

Findings

The study show that SC coordination is possible when both the supplier and the manufacturer choose LTT contract. This study not only identifies the influence of contract sequence on profit distribution among SC agents, but also establishes cut-off policies for all SC agents for each contract sequence. This study also examine the influence of chosen contract sequence on optimal profit distribution among SC agents.

Research limitations/implications

Three-echelon SC coordination under uncertain environment depends upon the contract sequence chosen by SC agents.

Practical implications

This study results will be helpful to managers of various SCs to take operational decisions under uncertain situations.

Originality/value

The main contribution of this study is that it explores the possibility of coordination by supply contracts for three-echelon SC in a fuzzy environment.

Details

Benchmarking: An International Journal, vol. 30 no. 1
Type: Research Article
ISSN: 1463-5771

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Article
Publication date: 12 March 2018

Shekhar Shukla, B.K. Mohanty and Ashwani Kumar

The purpose of this paper is to highlight an innovative approach to explore and evaluate the sustainability perspectives in e-commerce channels for additive manufacturing (AM)…

1033

Abstract

Purpose

The purpose of this paper is to highlight an innovative approach to explore and evaluate the sustainability perspectives in e-commerce channels for additive manufacturing (AM). This approach helps the stakeholders to perform strategic planning dependent on a scenario-based analysis.

Design/methodology/approach

The paper structures the problem of understanding the sustainability perspectives of e-commerce channels for AM using value-focused thinking to identify the related fundamental objectives. These objectives assist in creating dynamic scenarios based on fuzzy cognitive maps of different e-commerce channels for AM.

Findings

To evaluate the proposed research methodology, four scenarios were developed for each e-commerce channel for AM. The exploration and evaluation of one of these scenarios assisted in explaining the whereabouts of the process to aid in strategizing decision situations and understanding these channels better from the sustainability perspective.

Practical implications

The approach presented in this paper can be used by the practitioners to perform strategic planning for prioritizing sustainability in e-commerce channels for AM; considering the consequences and trade-offs wrt the other factors. Moreover, the scenario-based analysis can be performed depending on the problem requirements of the stakeholder.

Originality/value

The paper addresses the gap of understanding the theoretical aspect of the sustainability perspective in e-commerce channels for AM and the practical aspect of exploring and evaluating them. A scenario-based analysis for each e-commerce channel based on the fundamental objectives of sustainability provides insights for implementation and directions for future research.

Details

Industrial Management & Data Systems, vol. 118 no. 2
Type: Research Article
ISSN: 0263-5577

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Article
Publication date: 12 February 2018

Alivarani Mohapatra, Byamakesh Nayak and Kanungo Barada Mohanty

This paper aims to propose a simple, derivative-free novel method named as Nelder–Mead optimization algorithm to estimate the unknown parameters of the photovoltaic (PV) module…

171

Abstract

Purpose

This paper aims to propose a simple, derivative-free novel method named as Nelder–Mead optimization algorithm to estimate the unknown parameters of the photovoltaic (PV) module considering the environmental conditions.

Design/methodology/approach

At a particular temperature and irradiation, experimental current-voltage (I-V) and power-voltage (P-V) characteristics are drawn and considered as a reference model. The PV system model with unknown model parameters is considered as the adaptive model whose unknown model parameters are to be adapted so that the simulated characteristics closely matches with the experimental characteristics. A single diode (Rsh) model with five unknown model parameters is considered here for the parameter estimation.

Findings

The key advantages of this method are that parameters are estimated considering environmental conditions. Experimental characteristics are considered for parameter estimation which gives accurate results. Parameters are estimated considering both I-V and P-V curves as most of the applications demand extraction of the actual power from the PV module.

Originality/value

The proposed model is compared with other three well-known models available in the literature considering various statistical errors. The results show the superiority of the proposed model with a minimum error for both I-V and P-V characteristics.

Details

World Journal of Engineering, vol. 15 no. 1
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 16 April 2020

Nikhil Pachauri

In a power system, the purpose of automatic voltage regulator (AVR) is the voltage control of synchronous generator. Power system stability and security depends on the AVR.

237

Abstract

Purpose

In a power system, the purpose of automatic voltage regulator (AVR) is the voltage control of synchronous generator. Power system stability and security depends on the AVR.

Design/methodology/approach

The present work is concentrated on the precise terminal voltage control of AVR system and simultaneously maintaining the stability of the system. Therefore, an optimal proportional–integral–derivative (PID) controller is proposed. An optimization technique inspired from Mother Nature, i.e. water cycle algorithm (WCA) is used to evaluate the optimum parameter values of PID controller leading to WCA-tuned PID (WCA-PID). The performance of WCA-PID is compared with other controller reported in the literature.

Findings

Simulation results show that WCA-PID regulates the terminal voltage more preciously and accurately in comparison to other controller. Further, it is more robust toward parametric uncertainty, set-point tracking and disturbance rejection in comparison to other controller reported in the literature.

Originality/value

The work is not published anywhere else.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 39 no. 3
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 12 March 2019

Prakash Chandra Sahu, Ramesh Chandra Prusty and Sidhartha Panda

The paper has proposed to implement gray wolf optimization (GWO)-based filter-type proportional derivative with (FPD) plus (1+ proportional integral) multistage controller in a…

135

Abstract

Purpose

The paper has proposed to implement gray wolf optimization (GWO)-based filter-type proportional derivative with (FPD) plus (1+ proportional integral) multistage controller in a three-area integrated source-type interlinked power network for achieving automatic generation control.

Design/methodology/approach

For analysis, a three area interconnected power system of which each area comprises three different generating units where thermal and hydro system as common. Micro sources like wind generator, diesel generator and gas unit are integrated with area1, area2 and area3 respectively. For realization of system nonlinearity some physical constraints like generation rate constraint, governor dead band and boiler dynamics are effected in the system.

Findings

The supremacy of multistage controller structure over simple proportional integral (PI), proportional integral, derivative (PID) and GWO technique over genetic algorithm, differential evolution techniques has been demonstrated. A comparison is made on performances of different controllers and sensitivity analysis on settling times, overshoots and undershoots of different dynamic responses of system as well as integral based error criteria subsequent a step load perturbation (SLP). Finally, sensitive analysis has been analyzed by varying size of SLP and network parameters in range ±50 per cent from its nominal value.

Originality/value

Design and implementation of a robust FPD plus (1 + PI) controller for AGC of nonlinear power system. The gains of the proposed controller are optimized by the application of GWO algorithm. An investigation has been done on the dynamic performances of the suggested system by conducting a comparative analysis with conventional PID controller tuned by various optimization techniques to verify its supremacy. Establishment of the robustness and sensitiveness of the controller by varying the size and position of the SLP, varying the loading of the system randomly and varying the time constants of the system.

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Article
Publication date: 10 August 2021

B.N. Mohan Kumar and H.G. Rangaraju

Digital signal processing (DSP) applications such as finite impulse response (FIR) filter, infinite impulse response and wavelet transformation functions are mainly constructed…

67

Abstract

Purpose

Digital signal processing (DSP) applications such as finite impulse response (FIR) filter, infinite impulse response and wavelet transformation functions are mainly constructed using multipliers and adders. The performance of any digital applications is dependent on larger size multipliers, area and power dissipation. To optimize power and area, an efficient zero product and feeder register-based multiplier (ZP and FRBM) is proposed. Another challenging task in multipliers is summation of partial products (PP), results in more delay. To address this issue, the modified parallel prefix adder (PPA) is incorporated in multiplier design. In this work, different methods are studied and analyzed for designing FIR filter, optimized with respect to area, power dissipation, speed, throughput, latency and hardware utilization.

Design/methodology/approach

The distributed arithmetic (DA)-based reconfigurable FIR design is found to be suitable filter for software-defined radio (SDR) applications. The performance of adder and multipliers in DA-FIR filter restricts the area and power dissipation due to their complexity in terms of generation of sum and carry bits. The hardware implementation time of an adder can be reduced by using PPA which is based on Ling equation. The MDA-RFIR filter is designed for higher filter length (N), i.e. N = 64 with 64 taps and this design is developed using Verilog hardware description language (HDL) and implemented on field-programmable gate array. The design is validated for SDR channel equalizer; both RFIR and SDR are integrated as single system and implemented on Artix-7 development board of part name XC7A100tCSG324.

Findings

The MDA-RFIR for N = 64 is optimized about 33% in terms of area-delay, power-speed product and energy efficiency. The theoretical and practical comparisons have been done, and the practically obtained results are compared with existing DA-RFIR designs in terms of throughput, latency, area-delay, power-speed product and energy efficiency are better about 3.5 times, 31, 45 and 29%, respectively.

Originality/value

The MDA-RFIR for N = 64 is optimized about 33% in terms of area-delay, power-speed product and energy efficiency.

Details

International Journal of Pervasive Computing and Communications, vol. 18 no. 1
Type: Research Article
ISSN: 1742-7371

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Article
Publication date: 27 September 2021

Swati Sucharita Pradhan, Raseswari Pradhan and Bidyadhar Subudhi

The dynamics of the PV microgrid (PVMG) system are highly nonlinear and uncertain in nature. It is encountered with parametric uncertainties and disturbances. This system cannot…

118

Abstract

Purpose

The dynamics of the PV microgrid (PVMG) system are highly nonlinear and uncertain in nature. It is encountered with parametric uncertainties and disturbances. This system cannot be controlled properly by conventional linear controllers. H controller and sliding mode controller (SMC) may capable of controlling it with ease. Due to its inherent dynamics, SMC introduces unwanted chattering into the system output waveforms. This paper aims to propose a controller to reduce this chattering.

Design/methodology/approach

This paper presents redesign of the SMC by modifying its sliding surface and tuning its parameters by employing water-evaporation-optimization (WEO) based metaheuristic algorithm.

Findings

By using this proposed water-evaporation-optimization algorithm-double integral sliding mode controller (WEOA-DISMC), the chattering magnitude is diminished greatly. Further, to examine which controller between H8 controller and proposed WEOA-DISMC performs better in both normal and uncertain situations, a comparative analysis has been made in this paper. The considered comparison parameters are reference tracking, disturbance rejection and robust stability.

Originality/value

WEO tuned DISMC for PVMG system is the contribution.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 40 no. 5
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 2 April 2019

Kanungo Barada Mohanty, Kishor Thakre, Aditi Chatterjee, Ashwini Kumar Nayak and Vinaya Sagar Kommukuri

This study aims to propose a modified topology for an asymmetric multilevel inverter as a basic module that generates 13-level output voltage waveform. The basic module consists…

86

Abstract

Purpose

This study aims to propose a modified topology for an asymmetric multilevel inverter as a basic module that generates 13-level output voltage waveform. The basic module consists of eight switches (unidirectional and bidirectional switch) and four DC voltage sources with unequal magnitudes. The proposed topology reduces the number of switches, isolated DC sources, cost and size of the circuit significantly as compared to other topologies. In addition, the proposed circuit provides a modular structure for a multilevel inverter.

Design/methodology/approach

The proposed configuration is implemented through simulation and hardware development of a single-phase 13-level inverter prototype. A multicarrier-based pulse width modulation scheme is adopted for generating switching signals by using dSPACE real-time controller.

Findings

To demonstrate the advantages of the proposed configuration, a comparative analysis is carried out with other multilevel topologies in terms of number of switches, gate driver circuits, on-state switches and blocking voltage on the switches. The comparison results confirmed that the proposed configuration requires less number of components for the same number of voltage levels. Moreover, the peak inverse voltage on switches and losses is lower in the proposed configuration.

Originality/value

In the available literature, numerous topologies are presented with main emphasis on the reduced components count. In this study, the authors proposed a new topology for an asymmetrical source configuration. The performance of the proposed topology under steady-state and dynamic conditions is evaluated using simulation and experimental implementation.

Details

World Journal of Engineering, vol. 16 no. 1
Type: Research Article
ISSN: 1708-5284

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Article
Publication date: 6 February 2017

Mica Grujicic, S. Ramaswami and Jennifer Snipes

Nacre is a biological material constituting the innermost layer of the shells of gastropods and bivalves. It consists of polygonal tablets of aragonite, tessellated to form…

422

Abstract

Purpose

Nacre is a biological material constituting the innermost layer of the shells of gastropods and bivalves. It consists of polygonal tablets of aragonite, tessellated to form individual layers and having the adjacent layers as well as the tablets within a layer bonded by a biopolymer. Due to its highly complex hierarchical microstructure, nacre possesses an outstanding combination of mechanical properties, the properties which are far superior to the ones that are predicted using techniques such as the rule of mixtures. Given these properties, a composite armor the structure of which mimics that of nacre may have improved performance over a monolithic armor having a similar composition and an identical areal density. The paper aims to discuss these issues.

Design/methodology/approach

In the present work, an attempt is made to model a nacre-like composite armor consisting of B4C tablets and polyurea tablet/tablet interfaces. The armor is next tested with respect to impact by a solid right circular cylindrical (SRCC) rigid projectile, using a transient non-linear dynamics finite-element analysis. The ballistic-impact response and the penetration resistance of the armor are then compared with that of the B4C monolithic armor having an identical areal density. Furthermore, the effect of various nacre microstructural features (e.g. surface profiling, micron-scale asperities, mineral bridges between the overlapping tablets lying in adjacent layers, and B4C nano-crystallinity) on the ballistic-penetration resistance of the composite armor is investigated in order to identify an optimal nacre-like composite armor architecture having the largest penetration resistance.

Findings

The results obtained clearly show that a nacre-like armor possesses a superior penetration resistance relative to its monolithic counterpart, and that the nacre microstructural features considered play a critical role in the armor-penetration resistance.

Originality/value

The present work indicates that for a given choice of armor material, penetration resistance may be improved by choosing a structure resembling that of nacre.

Details

International Journal of Structural Integrity, vol. 8 no. 1
Type: Research Article
ISSN: 1757-9864

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Article
Publication date: 12 June 2017

Mica Grujicic, Jennifer Snipes and S. Ramaswami

The purpose of this paper is to model a nacre-like composite material, consisting of tablets and polyurea tablet/tablet interfaces, B4C. This composite material is being…

317

Abstract

Purpose

The purpose of this paper is to model a nacre-like composite material, consisting of tablets and polyurea tablet/tablet interfaces, B4C. This composite material is being considered in the construction of the so-called backing-plate, a layer within a multi-functional/multi-layer armor system.

Design/methodology/approach

Considering the basic functions of the backing-plate (i.e. to provide structural support for the ceramic-strike-face and to stop a high-velocity projectile and the accompanying fragments) in such an armor system, the composite-material architecture is optimized with respect to simultaneously achieving high flexural stiffness and high ballistic-penetration resistance. Flexural stiffness and penetration resistance, for a given architecture of the nacre-like composite material, are assessed using a series of transient non-linear dynamics finite-element analyses. The suitability of the optimized composite material for use in backing-plate applications is then evaluated by comparing its performance against that of the rolled homogeneous armor (RHA), a common choice for the backing-plate material.

Findings

The results obtained established: a trade-off between the requirements for a high flexural stiffness and a high ballistic-penetration resistance in the nacre-like composite material; and overall superiority of the subject composite material over the RHA when used in the construction of the backing-plate within multi-functional/multi-layer armor systems.

Originality/value

This study extends the authors previous research on nacre-mimetic armor to optimize the architecture of the armor with respect to its flexural stiffness and ballistic-penetration resistance, so that these properties could be increased over the levels attained in the current choice (RHA) for the backing layer of multi-functional/multi-layer armor.

Details

International Journal of Structural Integrity, vol. 8 no. 3
Type: Research Article
ISSN: 1757-9864

Keywords

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