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The equation of motion of a beam on multiple supports, subject to prescribed time‐dependent conservative axial loads, is formulated based on Hamilton’s principle and the assumed mode method. The effects of sinusoidal perturbations in respect of the axial loads are then examined using Bolotin’s method. The respective regions of instability are determined by converting the resulting equations of boundary frequencies into the standard form of a generalized eigenvalue problem. Instability regions are presented for various combinations of support configuration, average value and amplitude of the sinusoidal perturbations of the axial loads.

The purpose of this paper is to review the nature and extent of foodborne diseases in India due to chemical and microbial agents.

The scientific investigations/reports on outbreak of foodborne diseases in India for the past 29 (1980‐2009) years due to adulteration, chemical, and microbiological contamination have been reviewed. Reported scientific information on foodborne pathogens detected and quantified in Indian foods has also been reviewed.

A total of 37 outbreaks involving 3,485 persons who have been affected due to food poisoning have been reported in India. Although the common forms of foodborne diseases are those due to bacterial contamination of foods, however, higher numbers of deaths have been observed due to chemical contaminants in foods.

A national foodborne disease surveillance system needs to be developed in India in order to enable effective detection, control and prevention of foodborne disease outbreaks.

The equation of motion of a free‐free moving column with a prescribed axial acceleration is formulated based on Hamilton’s principle and the assumed mode method. The slender column is used as a simple model for a missile or a launched vehicle. The column is under the action of aerodynamic forces which are modelled as axial external loads at the ends of the column. The effects of axial sinusoidal perturbations in respect of axial acceleration and the external loads are then examined using Bolotin’s method. The respective regions of instability are determined by converting the resulting equations of boundary frequencies to the standard form of a generalized eigenvalue problem. Instability regions for various combinations of external loads and axial acceleration of the column are presented.

Purpose – The aggregate investment by foreign institutional investors (FIIs) in the Indian stock market is significant compared to that by domestic institutions and individual (retail) investors. The question of whether FIIs exhibit herding and positive feedback trading while investing in the Indian stock markets has not been examined so far. This study is an attempt to fill the gap and contribute to the existing evidence on foreign portfolio investment in India.

Methodology/approach – We have analyzed the daily data on purchases and sales of securities by FIIs sourced from the Securities and Exchange Board of India (SEBI), and the Bombay Stock Exchange (BSE). We have adopted the approach of Lakonishok et al. (1992), and Wermers (1999) to examine herding and positive feedback trading by foreign investors.

Findings – Our results suggest that FIIs exhibit herding and positive feedback trading during different phases of the stock market. This observed behavior is prominent in but not restricted to large cap stocks as they enjoy better liquidity.

Social implication – The herding and positive feedback trading by FIIs is a cause for concern for government of India, capital market regulator (SEBI), and the country's central bank (RBI) as it adversely affects stock prices and volatility. They are required to formulate and implement a suitable policy response given their objective of protecting the interests of small investors in the market. They may also have to monitor the purchases and sales of equities by FIIs in general and of better performing large cap stocks in particular.

This study is intended to investigate the volatility patterns in Bombay Stock Exchange Limited Sensitivity Index (BSE Sensex) based on time series data collected for 10 years period of time. To reach out the predefined objectives of the study, the authors have employed generalized autoregressive conditional heteroscedastic models. The study revealed that the presence of heteroscedasticiy is found in BSE Sensex. Further, the model produced highly accurate results when the researchers compared the estimated results from actual. Furthermore, the volatility of BSE Sensex has shown the features of clustering and significant time varying. Moreover, the model has indicated that there is a positive correlation between daily stock returns and the BSE Sensex volatility.

Heat exchangers (HEXs) are extensively used in many applications such as heating and cooling systems. To increase the thermal performance of HEXs, nano-sized particles could be added to the base working fluid which can improve the thermophysical properties of the fluid. In addition, further improvement in the thermal performance of nanofluids can be obtained by using two or more different nanoparticles which are known as hybrid nanofluids. This paper aims to improve the thermal efficiency of U-type tubular HEX (THEX) by using CuO-Al₂O₃/water hybrid nanofluid.

Numerical simulation has been used to model THEX with various configurations. Also, CuO-Al₂O₃/water hybrid nanofluid has been experimented in THEX in two various modes including parallel (PTHEX) and counter flow (CTHEX) regarding to the numerical findings. Hybrid nanofluids have been prepared in two particle concentrations and compared with CuO/water nanofluid at the same concentrations and also with water.

The numerical simulation results showed that adding fins and also using hybrid nanofluid can increase heat transfer rate in HEX. However, adding fins cannot be a good option in U-type THEX with lower diameter because it increases pressure drop notably. Experimental results of this work illustrated that using Al₂O₃-CuO/water hybrid nanofluid in the THEX improved thermal performance significantly. Maximum enhancement in overall heat transfer coefficient of THEX by using CuO-Al₂O₃/water nanofluid in 0.5% and 1% concentrations achieved as 9.5% and 12%, respectively.

The obtained findings of the study showed the positive effects of using hybrid type nanofluid in comparison with single type nanofluid. In this study, numerical and experimental analysis have been conducted to investigate the effect of using hybrid type nanofluid in U-type HEX. The obtained results exhibited successful utilization of CuO-Al₂O₃/water hybrid type nanofluid in HEX. Moreover, it was observed that thermal performance analysis of the nanofluids without any experiment can be done by using numerical method.

This paper investigates herding behavior and its persistence among foreign institutional investors (FIIs) in the individual stocks of the energy sector of Indian stock exchange by focusing on post turmoil period. The study also examines the relation of herding with the individual return, market return, trading volume and conditional volatility of individual and market return.

The presence of herding is investigated by Lakonishok et al. (1992) model, value-based and count-based herd ratio measure among FIIs in individual stock of energy sector post turmoil period. Further, run test was employed to check the persistency in herding and multivariate distributed lag to investigate the relationship with the market determinant.

The result indicates the existence of herding in most of the companies and strong persistence in all the companies. The intensity of buy side herding is higher than sell side. Herding and individual return both are significant driving forces of FIIs herding, while trading volume and market volatility in few companies exhibit inverse relationship.

This study is limited to investigation of energy sector stock.

Stock market is significantly influenced by FIIs and their propensity to herd may generate instability in the stock market. Therefore, regulatory authority should continuously monitor the flow of fund by FIIs.

Herding in the individual stock of the energy sector was not previously performed.

The purpose of this paper is to develop an algorithm and software for determining the size of a line-start permanent magnet synchronous motor (LSPMSMs) based on its optimization.

The software consists of an optimization procedure that cooperates with a FEM model to provide the desired behavior of the motor under consideration. The proposed improved version of the genetic algorithm has modifications enabling efficient optimization of LSPMSMs. The objective function consists of three important functional parameters describing the designed machine. The 2-D field-circuit mathematical model of the dynamics operation of the LSPMSMs consists of transient electromagnetic field equations, equations describing electric windings and mechanical motion equations. The model has been developed in the ANSYS Maxwell environment.

In this proposed approach, the set of design variables contains the variables describing the stator and rotor structure. The improved procedure of the optimization algorithm makes it possible to find an optimal motor structure with correct synchronization properties. The proposed modifications make the optimization procedure faster and more

This proposed approach can be successfully applied to solve the design problems of LSPMSMs.

This case describes the challenges faced by Amul in organising dairy farmers into a co-operative and creating continuous opportunities for value addition. Participants in the case discussion are required to review the developments in the organisation and recommend a strategy for the future.