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This paper aims to analyze deeply the effect of surface roughness conditions of the common interface of the two-layered riveted cantilever beams on their frictional damping during free lateral vibration at first mode. Here, the product, (µ × α), and damping ratio, ξ, are the parameters whose variations are analyzed in this investigation. For this, the influencing parameters considered are the natural frequency of vibration, f; the amplitude of initial excitation, y; and surface roughness value, Ra.

For experimentally evaluating logarithmic damping decrement, d, the frequency response function analyzer for the case of free lateral vibrations was used. Later, for evaluating the product, µ × α (where µ is the kinematic coefficient of friction and α is the dynamic slip ratio), and then, the damping ratio, ξ, the empirical relation suggested for logarithmic damping decrement, d, of riveted cantilever beams was used. After this, the full and reduced quadratic models of the product, µ × α, ξ, response surface methodology (RSM) with the help of Design Expert 11 software was used. Corresponding main effects plots, surface plots and prediction comparison plots were obtained to observe the variations of the product, µ × α, ξ for the variations of influencing parameters: f, y and Ra. Finally, a machine learning technique such as artificial neural networks (ANNs) using “nntool” present in MATLAB R13a software was used to predict the ξ for the different combinations of f, y and Ra.

The full and reduced quadratic regression models for the product, (µ × α) and the damping ratio, ξ of riveted cantilever beams for free lateral vibrations of the first mode in terms of the parameters: f, y and Ra were obtained. In addition, the main effects plots, surface plots and prediction comparison plots for the product, µ × α, ξ, with the corresponding experimental values of the product, µ × α, ξ, were obtained. Also, the execution of ANNs using MATLAB R13a software is proved to be the more accurate tool for the prediction of damping ratios in comparison to quadratic regression equations obtained from Design Expert 11 software. In the end, the assumption that the effect of surface roughness value on the product, (µ × α), and the damping ratio, ξ, is negligible is proved to be true using the main effects plots for the product, (µ × α) and ξ obtained from the Design Expert 11 software.

Obtaining the full and reduced quadratic regression equations for the product, (µ × α), and ξ of the two-layered riveted cantilever beams in terms of parameters: f, y and Ra was done. In addition, the conditions for the corresponding minimum and maximum values of the product, (µ × α), and ξ were obtained. Later, the main effects plots, surface plots and comparison plots of the predicted product, (µ × α), and ξ versus experimental product, (µ × α), and ξ were also obtained. Finally, the predicted values of the product, (µ × α), and ξ using the ANNs tool are observed to be the more accurate values in comparison to that obtained from RSM using the Design Expert 11 software.

The objective of the paper is to evaluate the fabrication process and to study the influence of process parameters of friction stir processing of 6061-TiB₂-Al₂O₃ Aluminum alloy surface composite on microhardness tensile strength, and microstructure.

Friction stir processing method is used for attaining the desired mechanical properties, and selectively processed reinforcements to fabricate the samples. The Taguchi technique was used to optimize rotational speed, travel speed and volume percentage of reinforcement particles to enhance the mechanical properties of 6061-TiB₂-Al₂O₃ Aluminum alloy composite.

The fabrication of surface composites through FSP allows new inventions in terms of material with enhanced surface layers without changing the base metal.

To examine the behavior of the surface of the composites in the different zones, the practical implication consists of the use of different characterization techniques like optical microscopy and scanning microscopy for microstructural behavior and the measurement of hardness and tensile tests for mechanical behavior.

The research work consists of tool design and process parameters, which can affect the final product (microstructural changes), and the performance of the modified surface layer behavior was studied and presented.

Medical textile is one aspect of technical textiles and it is classified according to performance and functional properties for hygienic and healthcare products. Seaweeds have curative powers for curing most degenerative diseases. The paper aims to discuss these issues.

The present study focusses on the extraction of dyes from five seaweeds such as Ulva reticulata, Ulva lactuca, Sargassum wightii, Padina tetrastomatica and Acanthophora spicefera. The presence of bioactive compounds, antioxidant and antimicrobial properties of dye extracted from seaweeds was analysed. The dye extracted from green seaweed was applied on cotton fabric to obtain antimicrobial and other properties used to make non- implantable materials.

A maximum antioxidant inhibition percentage of 86.48+2.84 and a maximum antibacterial activity of 27 mm inhibition zone were obtained on the fabric treated with the dye extract from the Ulva lactuca seaweed. The physical properties such as tensile strength and tearing strength did not show much significant difference in untreated and treated fabric. The air permeability, water absorbency and wicking behaviour of treated fabric were reduced compared with untreated fabric. The washing and rubbing properties of treated fabric were very good after repeated washing.

This bioactive fabric has been used for non-implantable materials such as wound healing, face mask, surgical gowns and hygienic textiles in recent years.

Gives a bibliographical review of the finite element methods (FEMs) applied for the linear and nonlinear, static and dynamic analyses of basic structural elements from the theoretical as well as practical points of view. The range of applications of FEMs in this area is wide and cannot be presented in a single paper; therefore aims to give the reader an encyclopaedic view on the subject. The bibliography at the end of the paper contains 2,025 references to papers, conference proceedings and theses/dissertations dealing with the analysis of beams, columns, rods, bars, cables, discs, blades, shafts, membranes, plates and shells that were published in 1992‐1995.

General Management/Strategy.

Post-graduate/MBA.

Case A: Mr Grandhi Mallikarjuna Rao, founding chairman of GMR, was considering a proposal to bid for an upcoming international airport in Hyderabad, India. The strategic move would have marked GMR’s foray into the Indian airport infrastructure sector. GMR had been involved in the development and operation of power plants and had thrived on public–private partnerships for all its projects. Mr Rao is thinking: Should GMR make another major investment in infrastructure development by bidding to build the airport in Hyderabad, India? Further, how should the organization prepare itself for this strategic move? Case B: On April 4, 2013, the meeting of GMR’s Group Executive Council (GEC) was scheduled to take place. Srinivivas Bommidala, G.M. Rao’s son-in-law and Chairman of GMR’s airports business, was gearing up for the meeting. The meeting was called to discuss a proposal for bidding for an upcoming airport project in the Philippines. It had been more than a decade since GMR entered the airport infrastructure sector. The organization had built substantial airport operating expertise during that period. It adopted a joint venture (JV) model for expanding in the airport infrastructure business. Until now, the organization had always formed JVs for all its airport projects. JVs with existing airport operators were necessitated by the bid conditions that required a certain minimum airport operating experience for qualifying as a bidder for various projects. In some cases, a JV with a local player helped GMR with market knowledge for functioning in a foreign market. GMR also used JVs to access the capabilities it lacked for operating in this sector and gradually learnt from its partners for building capabilities in-house. The group now had the required operating expertise in the sector to qualify as a bidder. One of the key issues the GEC was contemplating was: Whether GMR should continue to form JV for bidding for the upcoming project or should it go solo? Further, if it had to form a JV then, in which areas should it seek a partner?

Case A: To understand the relationship between key concepts in strategic management, including diversification, capabilities and core competence. To help students understand the various factors managers consider when deciding on the diversification strategy of an organization. To create an understanding of the organizational processes required to facilitate diversification into a new segment. To teach students how to evaluate a potential market opportunity that may require a firm to take on a diversification strategy. Case B: To help students understand how companies use alliances as growth strategies. To understand the rationale for formation of various alliances. To explore various factors managers consider when deciding on alliance strategy of an organization. To understand the challenges associated with using alliances as a strategic option. To understand the pros and cons of internal development (i.e. going solo) vis-à-vis strategic alliances.

CSS 11: Strategy.

This study examines whether the current virus pandemic (COVID-19) has any significant negative effect on returns series of selected stock markets in the developed, Asian and GCC countries. For this purpose, the EGARCH (1, 1) model and the News Impact Curve (NIC) are applied to examine the persistence of symmetric volatility, leverage-effect and inducing volatility by preceding bad or good news. The findings suggest that the volatility is persistent in all stock markets, but it is under unity for many stock markets, which means the volatility will persist for the short term in most cases. Furthermore, the findings of asymmetric volatility analysis indicate the presence of leverage-effect over the study period in all the selected stock markets except Japan, Indonesia and Hong Kong. However, NIC plots provide evidence that the negative shock (news) of the COVID-19 outbreak would put forward a higher volatility on all selected stock market returns in the near future, except for the stock markets in Thailand, Japan and Singapore, where the shocks (positive) suggest a higher subsequent period of conditional variance compared to the current shocks (negative) of the COVID-19 pandemic. Consequently, understanding the volatility structure of stock market returns is imperative for policy guidance among the policymakers and potential investors. For policymakers, as the volatility caused by the COVID-19 outbreak is persistent for the short term, this may encourage governments and central banks to implement effective measures to stimulate fiscal and monetary policies to counter the distraction caused by the pandemic, support the economic activities and cushion the local firms from the pandemic effect. For investors, the findings suggest that long-term investment decision should be taken to invest in all stock markets that are negatively affected by the COVID-19 outbreak to achieve capital gain in the future, while short-term investment decisions may be undertaken to take advantage from the short-term market volatility.

Amaranth leaves which are an excellent source of calcium, iron, β‐carotene and protein, grow as a weed during the rainy season in Haryana State. This study aims to incorporate nutrient dense dried amaranth leaves powder in products commonly consumed in Haryana State, India.

Fresh amaranth leaves were dried at 50 ± 5 ^○C. The products like biscuits, mathi, matar and sev commonly consumed in Haryana State, were prepared using 5 per cent dried amaranth leaf powder. Amaranth leaf powder was not added in the products which served as control. The nutrient composition of the prepared products was analysed. The nutrient composition of control and supplemented products was compared.

The supplemented products like biscuit, mathi, matar and sev had significantly higher protein, fat, ash and fibre contents as compared to their control. The total soluble sugar, reducing sugar and non reducing sugar content of supplemented biscuit was significantly higher than control biscuit. The phytic acid and tannin content significantly increased and in vitro protein and starch digestibility significantly decreased in all the supplemented products as compared to their respective controls. Supplemented biscuit had about one and a half times higher Ca and supplemented mathi and matar had double the amount of Ca than their respective controls. The increase in Mg, Fe and Zn content in all the supplemented products was significant.

Amaranth leaves are abundantly available during the rainy season, and can be successfully incorporated in commonly consumed food products without adding any extra cost.

Amaranth leaf powder supplemented products are a very good source of protein, fibre, calcium and iron. Consumption of such value added products may contribute in improving the nutritional status of the population especially the vulnerable section.

This paper aims to analyze and give directions for advancing research in stock market volatility highlighting its features, structural breaks and emerging developments. This study offers a platform to research the benchmark studies to know the research gap and give directions for extending future research.

The author has performed the literature review, and, reference checking as per the snowballing approach. Firstly, the author has started with outlining and simplifying the significance of the subject area, the review illustrating the various elements along with the research gaps and emphasizing the finding.

This work summarizes the studies covering the volatility, its properties and structural breaks on various aspects such as techniques applied, subareas and the markets. From the review’s analysis, no study has clarified the supremacy of any model because of the different market conditions, nature of data and methodological aspects. The outcome of this research work has delivered further magnitude to research the benchmark studies for the upcoming work on stock market volatility. This paper has also proposed the hybrid volatility models combining artificial intelligence with econometric techniques to detect noise, sudden changes and chaotic information easily.

The author has taken the research papers from the scholarly journal published in the English language only and the author may also consider other nonscholarly or other language journals.

To the best of the author’s knowledge, this research work highlights an updated and more comprehensive framework examining the properties and demonstrating the contemporary developments in the field of stock market volatility.

The purpose of this paper is to study the effects of Soret and Dufour effects on convective heat and mass transfer flow through a porous medium in a rectangular duct in the presence of inclined magnetic field.

Using the non-dimensional variables, the governing equations have been transformed into a set of differential equations, which are non-linear and cannot be solved analytically, therefore finite element method has been used for solving the governing equations.

The influence of thermo-diffusion, diffusion thermo, radiation, dissipation, heat sources and the inclined magnetic field on all the flow, heat and mass transfer characteristics has been found to be significant.

The problem is relatively original as it combines many effects as Soret and Dufour effects and chemical reaction under inclined magnetic field.

The purpose of this paper is to present the optimal design of a simply supported variable curvature laminated angle-ply composite panel under uniaxial compression. The objective is to maximize the failure load which is defined as the minimum of the buckling load and the first-ply failure load.

The numerical results presented are obtained using a shear deformable degenerated shell finite element, a brief formulation of which is given. Some verification problems are solved and a convergence study is conducted in order to assess the accuracy of the element. The design procedure is presented and optimization results are given for a simply supported symmetric eight layer angle-ply panel composed of a flat and two cylindrical sections.

The influences of the stacking sequence and panel thickness on optimization are investigated and the effects of various problem parameters on the optimization procedure are discussed.

The paper shows that the load carrying capacity of thicker panels is considerably reduced when the first-ply failure constraint is taken into account.