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The purpose of this study is to investigate the bending analysis of metal (Ti-6Al-4V)-ceramic (ZrO₂) functionally graded material (FGM) sandwich plate with material property gradation along length and thickness direction under thermo-mechanical loading using inverse trigonometric shear deformation theory (ITSDT). FGM sandwich plate with a ceramic core and continuous variation of material properties has been modelled using Voigt’s micro-mechanical model following the power law distribution method. The impact of bi-directional gradation of material properties over the bending response of FGM plate under thermo-mechanical loading has been investigated in this work.

In this study, gradation of material properties for FGM plates is considered along length and thickness directions using Voigt’s micromechanical model following the power law distribution method. This type of FGM is called bi-directional FGMs (BDFGM). Mechanical and thermal properties of BDFGM sandwich plates are considered temperature-dependent in the present study. ITSDT is a non-polynomial shear deformation theory which requires a smaller number of field variables for modelling of displacement function in comparison to poly-nominal shear deformation theories which lead to a reduction in the complexity of the problem. In the present study, ITSDT has been utilized to obtain the governing equations for thermo-mechanical bending of simply supported uni-directional FGM (UDFGM) and BDFGM sandwich plates. Analytical solution for bending analysis of rectangular UDFGM and BDFGM sandwich plates has been carried out using Hamilton’s principle.

The bending response of the BDFGM sandwich plate under thermo-mechanical loading has been analysed and discussed. The present study shows that centre deflection, normal stress and shear stress are significantly influenced by temperature-dependent material properties, bi-directional gradation exponents along length and thickness directions, geometrical parameters, sandwich plate layer thickness, etc. The present investigation also reveals that bi-directional FGM sandwich plates can be designed to obtain thermo-mechanical bending response with an appropriate selection of gradation exponents along length and thickness direction. Non-dimensional centre deflection of BDFGM sandwich plates decreases with increasing gradation exponents in length and thickness directions. However, the non-dimensional centre deflection of BDFGM sandwich plates increases with increasing temperature differences.

For the first time, the FGM sandwich plate with the bi-directional gradation of material properties has been considered to investigate the bending response under thermo-mechanical loading. In the literature, various polynomial shear deformation theories like first-order shear deformation theory (FSDT), third-order shear deformation theory (TSDT) and higher-order shear deformation theory (HSDT) have been utilized to obtain the governing equation for bending response under thermo-mechanical loading; however, non-polynomial shear deformation theory like ITSDT has been used for the first time to obtain the governing equation to investigate the bending response of BDFGM. The impact of bi-directional gradation and temperature-dependent material properties over centre deflection, normal stress and shear stress has been analysed and discussed.

The purpose of this paper is to carry out free vibration and buckling analysis of functionally graded material (FGM) plate.

Equilibrium and stability equations of FGM rectangular plate under different boundary conditions are derived using finite element method-based inverse trigonometric shear deformation theory (ITSDT). Eight-noded rectangular plate element with seven degrees of freedom at each node is used for the present analysis. The power-law distribution method has been considered for the continuously graded variation in composition of the ceramic and metal phases across the thickness of a functionally graded plate.

The finite element formulation incorporated with ITSDT and provisions of the constitutive model of FGM plate has been implemented in a numerical code to obtain the natural frequency and critical buckling load under uniaxial and biaxial compressive load. The influence of material gradation, volume fraction index, span to thickness ratio and boundary constraints over free vibration and buckling response has been studied.

Development and validation of finite element methodology using ITSDT to predict the structural response of the FGM plates under different loading, geometric and boundary conditions.

The purpose of this article is to carry out the thermal buckling analysis of power and sigmoid functionally graded material Sandwich plate (P-FGM and S-FGM) under uniform, linear, nonlinear and sinusoidal temperature rise.

Thermal buckling of FGM Sandwich plates namely, FGM face with ceramic core (Type-A) and homogeneous face layers with FGM core (Type-B), incorporated with nonpolynomial shear deformation theories are considered for an analytical solution in this investigation. Effective material properties and thermal expansion coefficients of FGM Sandwich plates are evaluated based on Voigt's micromechanical model considering power and sigmoid law. The governing equilibrium and stability equations for the thermal buckling analysis are derived based on sinusoidal shear deformation theory (SSDT) and inverse trigonometric shear deformation theory (ITSDT) along with Von Karman nonlinearity. Analytical solutions for thermal buckling are carried out using the principle of minimum potential energy and Navier's solution technique.

Critical buckling temperature of P-FGM and S-FGM Sandwich plates Type-A and B under uniform, linear, non-linear, and sinusoidal temperature rise are obtained and analyzed based on SSDT and ITSDT. Influence of power law, sigmoid law, span to thickness ratio, aspect ratio, volume fraction index, different types of thermal loadings and Sandwich plate types over critical buckling temperature are investigated. An analytical method of solution for thermal buckling of power and sigmoid FGM Sandwich plates with efficient shear deformation theories has been successfully analyzed and validated.

The temperature distribution across FGM plate under a high thermal environment may be uniform, linear, nonlinear, etc. In practice, temperature variation is an unpredictable phenomenon; therefore, it is essential to have a temperature distribution model which can address a sinusoidal temperature variation too. In the present work, a new sinusoidal temperature rise is proposed to describe the effect of sinusoidal temperature variation over critical buckling temperature for P-FGM and S-FGM Sandwich plates. For the first time, the FGM Sandwich plate is modeled using the sigmoid function to investigate the thermal buckling behavior under the uniform, linear, nonlinear and sinusoidal temperature rise. Nonpolynomial shear deformation theories are utilized to obtain the equilibrium and stability equations for thermal buckling analysis of P-FGM and S-FGM Sandwich plates.

The aim of this paper is to investigate the initiation and progress of damage in laminated composite shells at elevated moisture concentration and temperature due to low‐velocity impacts.

A finite element analysis procedure is developed to investigate the initiation and propagation of damage in laminated composite shells in hygrothermal environments.

It was found inter alia, that in the case of rise of temperature present FEM results match well with closed form solutions and that stress results at different levels of moisture concentration agree with the results published in the open literature.

The paper provides in‐depth insight into the progress of damage in laminated shell structures.

The paper investigates initiation and progress of damage in laminated composite shell structures due to low‐velocity impacts.

In the present investigation, a finite element analysis procedure is developed to predict the initiation and propagation of damages as well as to analyse damaged laminated composite plates under forced vibration and impact loads. Isoparametric quadratic plate bending element (nine‐noded rectangular) based on Mindlin plate theory is used to develop the FE codes for the present analysis. A phenomenological damage model assuming the effective stress concept is used to represent the damage of a lamina. The initiation and progress of damage due to forced vibration and low velocity impact are studied for different impactor velocities.

This paper examines the technical efficiency (TE) of Indian commercial banks during 1998–2015.

This study uses mathematical programming-based data envelopment analysis (DEA) methodology to measure technical efficiency of Indian banks. Further, Simar and Wilson (2007) double bootstrap procedure is applied to examine the determinants of efficiency of the Indian banks, by examining the effects of various bank specific and other contextual variables.

The results indicate substantial upward bias in the conventional efficiency estimates of the Indian commercial banks. Needless to note, such upward bias is consistent with the theoretical postulates. The bootstrapped regression results show that increasing capital adequacy ratio is positively associated with bank efficiency. The popular belief that non-performing assets have a dampening effect on performance of banks is validated. Among others, ownership category is observed to be an important determining factor of bank efficiency. Specifically, state-owned banks (SOBs) are relatively lagging behind the foreign banks. Moreover, larger banks are observed to have a significantly higher level of efficiency, therefore, recent official policy initiatives toward consolidation of SOBs are validated.

As this study uses Simar and Wilson (2007) bootstrap approach, it enables the authors to have an estimate of the extent of bias in the traditional DEA TE scores. It also helps us drawing consistent inferences by rectifying the problem of serial correlation in the conventional second stage regression in this regard.

India is one of the largest tea producers and consumers in the world. Around 70% of Indian tea is consumed by domestic consumers. The world famous Darjeeling and Assam tea are India’s pride. Once India was the top exporter of tea in the global market, currently, it is lagging behind China, Kenya, and Sri Lanka. In the global arena, Indian tea is facing stiff competition from China, Kenya, and Sri Lanka. With this backdrop, the present study aims to investigate twin objectives. First, the changing growth pattern of India’s tea export is investigated. Along with this, the impacts of trade openness on India’s tea export are also scrutinized. The entire study is conducted based on the secondary data, compiled from the various issues of Handbook of Statistics on Indian Economy published by Reserve Bank of India. The data are compiled for the period 1987–1988 to 2018–2019. The investigation of the first objective is facilitated by the Poirer’s Spline function approach. On the contrary, for the exploration of the second objective, we have calculated the “trade openness index.” The study concludes that initially with trade openness Indian tea industry was benefitting but the growth rate of tea export gets reduced over time. It is surprising that in the post-EXIM-2002–2007 phase the rate of growth of India’s tea exports has declined sharply. The study ends with suitable policy prescriptions.

Firms have been adopting lean manufacturing to improve their business performances. However, they are facing failures or less success in implementation, mainly due to lack of understanding in relating the lean practices (LPs) from the required performance measures perspective. In view of the lack of research and the importance of understanding them, the purpose of this paper is to prioritize LPs.

As LPs are scattered in the literature and a variety of performance measures are used, an extensive literature review is first carried out to identify the LPs and performance measures. The blend of interpretive structural modeling and interpretive ranking process interpretive tools is adopted in establishing the contextual relationship among LPs and then ranking them based on the performance measures. A three-dimensional priority matrix is proposed for better explanation of the results.

The proposed framework can help firms better understand LPs and their levels of importance in lean implementation.

The involvement of lean experts may produce some bias in evaluating the LPs.

The proposed framework can help practitioners to develop an industry-specific road-map for the result-oriented LP implementation. Based on the area of performance to be improved, practitioners can prioritize LPs for implementation.

This is the first study that provides a comprehensive review of LPs available in the literature and prioritizes them in accordance with performance with interpretive tools.

The purpose of this paper is to assess the present situation in the development of indigenous digital libraries in India. The study aims to evaluate different retrieval features of Indian digital libraries, especially those provide access to multilingual and multimedia documents.

For this study, eight digital libraries originated in India, which are available in 24×7 timeframe and accessible worldwide through the internet, have been identified and selected. The retrieval features and other information on these digital libraries have been collected mostly from their respective websites and from other published literature, annual reports, etc.

The paper finds that Indian digital libraries provide universal access to informative and culturally rich digital content related to South Asian region. The digitisation efforts in Indian institutions make these digital libraries operational.

The institutional repositories and open access archives of Indian institutions that give access to the current research literature are not included in this study, because their retrieval features are mostly similar to each other as they use either DSpace or GNU EPrints open source software.

Indigenous digital libraries in India provide universal access to information and knowledge related to culture and heritage of people of South Asian counties. This study gives an insight on how diverse contents are integrated and disseminated to the end‐users in a user‐friendly manner. This study also indicates research initiatives on different aspects of multilingual contents in this region.

No such evaluation on Indian digital libraries has been done from the perspective of information retrieval features. This study will generate new knowledge in area of indigenous digital libraries in a developing country like India. This study is also an attempt to popularise Indian indigenous digital libraries among the world community.

Indian textiles have a history of fine craftsmanship, and because of that, it has its own global appeal and international demand. India has its own extensive base of raw material and manufacturing. This makes India the second-largest textile exporter in the world after China. India's share in the global textiles and apparels trade was approximately 5% in 2017. In 2017, India's textile industry contributes 7% of total industry output and employs about 45 million people directly. Its contribution to the country's GDP and export earnings in the same year was 2% and 15%, respectively. With this backdrop, the present chapter aims to investigate twin objectives. Initially, the changing growth pattern of India's readymade garment export is investigated. Along with this, the impacts of trade openness on India's readymade garment export are also scrutinized. The entire study is conducted based on the secondary data, compiled from the various issues of “Handbook of Statistics on Indian Economy,” published by “Reverse Bank of India.” The data are compiled for the period 1987–1988 to 2018–2019. The investigation of the first objective is facilitated by the “Poirer's Spline function approach.” On the contrary, for the exploration of the second objective, we have calculated the “trade openness index.” It is measured as the sum of export and import as a percentage of GDP. The study concludes that the Indian readymade garment industry shows a declining growth rate and the industry is benefited from trade openness. The study ends with suitable policy prescriptions.