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A saturated iron core superconducting fault current limiter (SISFCL) has an important role to play in the present-day power system, providing effective protection against electrical faults and thus ensuring an uninterrupted supply of electricity to the consumers. Previous mathematical models developed to describe the SISFCL use a simple flux density-magnetic field intensity curve representing the ferromagnetic core. As the magnetic state of the core affects the efficient working of the device, this paper aims to present a novel approach in the mathematical modeling of the device with the inclusion of hysteresis.

The Jiles–Atherton’s hysteresis model is utilized to develop the mathematical model of the limiter. The model is numerically solved using MATLAB. To support the validity of model, finite element model (FEM) with similar specifications was simulated.

Response of the limiter based on the developed mathematical model is in close agreement with the FEM simulations. To illustrate the effect of the hysteresis, the responses are compared by using three different hysteresis characteristics. Harmonic analysis is performed and comparison is carried out utilizing fast Fourier transform and continuous wavelet transform. It is observed that the core with narrower hysteresis characteristic not only produces a better current suppression but also creates a higher voltage drop across the DC source. It also injects more harmonics in the system under fault condition.

Inclusion of hysteresis in the mathematical model presents a more realistic approach in the transient analysis of the device. The paper provides an essential insight into the effect of the core hysteresis characteristic on the device performance.

This paper investigates the selection of semiconductor switches used in contactless power transfer (CPT) system. In the present paper a single phase high frequency full bridge inverter using different semiconductor switches like IGBT, MPOSFET and GTO has been considered. Harmonic injection in input current of the inverter for different semiconductor switches has been analyzed using PSIM software. The THD of input current of the inverter for the particular switching device has been determined by using Fourier Transforms. It has been observed that THD in case of the IGBT is minimised.

The purpose of this paper is to understand the practices and policies unique to high-tech manufacturing start-ups in emerging economies, such as India. The study analyzes the main features and challenges of the high-tech manufacturing sector, and the way in which enabling environment including policy making, supply chain capability and related technologies through Industry 4.0 could be leveraged to foster growth.

The paper undertakes an exploratory approach through in-depth semi-structured interviews conducted with high-tech manufacturing firms in various stages of their growth. The paper provides evidence of the challenges that high-tech manufacturing firms face in India, the strategies they adopt and highlights the role of institutional structures and policies.

Findings show that high-tech manufacturing start-ups in India face various challenges in the upstream, production and downstream supply chain processes. Further, issues related to availability of quality material, quality suppliers, contracts, funding and access to markets remain. Results also show that enabling operational and financial levers could be created by policy makers and other stakeholders to help the high-tech manufacturing start-ups scale faster and create value.

This paper contributes to the R&D intensive industry and high-tech manufacturing literature in the context of emerging economies, such as India, and provides a rigorous overview of the start-up ecosystem in high-tech manufacturing.

The purpose of this paper is to examine the factors affecting the financial sustainability of the Indian Micro Finance Institutions (MFIs) post-Andhra Pradesh (AP) crisis

Regression analysis is used to test the significance of the independent variables on the variable of interest, i.e. the operational self-sustainability. Three-stage regression analysis, i.e. Partial F-test, residual analysis and Box–Cox-type transformations is applied to see the impact of the variables on financial sustainability of the Indian MFIs. The study is based on the data of the Indian MFIs during three fiscal years from 2010-2011 to 2012-2012 reported in the Microfinance Information Exchange (MIX).

The authors’ results indicate that in 2010-2011, the linear regression model seems to be good fit to the data, whereas in 2011-2012 and 2012-2013, the appropriateness of the linear regression models seems questionable (the error distribution seems to be skewed). It is observed that square root of the dependent variable exhibits adequate fit for 2011 and 2012. Therefore, a substantial change in the model for estimating sustainability of Indian MFIs is observed in the post-AP crisis era. It is observed that portfolio quality and capital management are important determinants for the financial sustainability of the MFIs.

This study identifies the factors affecting the sustainability of the Indian MFIs, especially after the reforms following the AP crisis in India. The study suggests that from 2012-2013, the factors such as write-off ratio, capital-to-asset ratio, ratio of financial revenue to assets and provision for loan impairment-to-asset ratio are the main factors which have significant impact on the operational self-sufficiency (OSS) of Indian MFIs. This indicates that the quality of portfolio must be improved to reduce the vulnerability of the Indian MFIs.

After the AP crisis, the performance of Indian MFIs is stabilized to a greater extent. The various performance indicators are improving.

The paper provides a detailed comparative analysis of the factors effecting financial sustainability of the Indian MFIs, before and after the regulatory reforms in 2011. A substantial change is observed after 2011-2012. Such a study on the Indian microfinance sector seems to be new (to the best of the authors’ knowledge).

The purpose of this study is to perform a detailed review on the numerical modeling of multiphase and multicomponent flows in microfluidic system using phase-field method. The phase-field method is of emerging importance in numerical computation of transport phenomena involving multiple phases and/or components. This method is not only used to model interfacial phenomena typical to multiphase flows encountered in engineering and nature but also turns out to be a promising tool in modeling the dynamics of complex fluid-fluid interfaces encountered in physiological systems such as dynamics of vesicles and red blood cells). Intrinsically, a priori unknown topological evolution of interfaces offers to be the most concerning challenge toward accurate modeling of moving boundary problems. However, the numerical difficulties can be tackled simultaneously with numerical convenience and thermodynamic rigor in the paradigm of the phase field method.

The phase-field method replaces the macroscopically sharp interfaces separating the fluids by a diffuse transition layer where the interfacial forces are smoothly distributed. As against the moving mesh methods (Lagrangian) for the explicit tracking of interfaces, the phase-field method implicitly captures the same through the evolution of a phase-field function (Eulerian). In contrast to the deployment of an artificially smoothing function for the interface as used in the volume of a fluid or level set method, however, the phase-field method uses mixing free energy for describing the interface. This needs the consideration of an additional equation for an order parameter. The dynamic evolution of the system (equation for order parameter) can be described by Allen–Cahn or Cahn–Hilliard formulation, which couples with the Navier–Stokes equation with the aid of a forcing function that depends on the chemical potential and the gradient of the order parameter.

In this review, first, the authors discuss the broad motivation and the fundamental theoretical foundation associated with phase-field modeling from the perspective of computational microfluidics. They subsequently pinpoint the outstanding numerical challenges, including estimations of the model-free parameters. They outline some numerical examples, including electrohydrodynamic flows, to demonstrate the efficacy of the method. Finally, they pinpoint various emerging issues and futuristic perspectives connecting the phase-field method and computational microfluidics.

This paper gives unique perspectives to future directions of research on this topic.