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This study aims to numerically study the three-dimensional (3D) flow field characteristics in a conical convergent divergent (CD) nozzle with an internal strut system to describe the effect of struts on producing a side force for thrust vectoring applications.

Struts are solid bodies. When inserted into the supersonic region of the axisymmetric CD nozzle, it induces a shock wave that causes an asymmetric pressure distribution predominantly over the internal surface of the diverging wall of the C-D nozzle, creating a net side force similar to the secondary injection thrust vectoring control method. Numerical simulations were performed by solving Unsteady Reynolds Averaged Navier–Stokes equations with re-normalized group k–ϵ turbulence model. Cylindrical struts of various heights positioned at different locations in the divergent section of the nozzle were investigated at a nozzle pressure of 6.61.

Thrust vectoring angle of approximately 3.8 degrees was obtained using a single cylindrical strut with a dimensionless thrust (%) and total pressure loss of less than 2.36% and 2.67, respectively. It was shown that the thrust deflection direction could also be changed by changing the strut insertion location. A strut located at half of the diverging length produced a higher deflection per unit total pressure loss.

Using a lightweight and high-temperature resistant material, such as a strut, strut insertion-based thrust vectoring control might provide an alternative thrust vectoring method in applications where a longer period of control is needed with a reduced overall system weight.

This study describes the 3D flow field characteristics which result in side force generation by a supersonic nozzle with an internal strut.

This study measures the impact of ICT on Malaysia’s aggregate output in the period 1965‐2005. It closes a gap in existing literature by using the 3SLS technique on a country specific study. Telecommunication penetration rate is used as a proxy for ICT and analysed in both macro‐economic and micro‐economic perspectives. The findings of this study suggest that there is a causal relation between ICT and aggregate output in Malaysia and that the MSC and the privatisation policy of the telecommunication sector, are found to be indifferent to achieving expected economic growth in Malaysia.

This paper aims to introduce the quasi impedance source inverter (qZSI)-based static compensator (STATCOM), which is incorporated into the hybrid distributed power generation system for enhancement of power quality. The distributed power generation system includes the photovoltaic (PV), wind energy conversion system (WECS) and battery energy storage system.

The WECS is used by the self-excited induction generator (SEIG) and the flywheel energy storage system (FESS). To regulate its terminal voltage and frequency, the SEIG requires adjustable volt-ampere reactive (VAR). A combination of a STATCOM and a fixed condenser bank usually serves to satisfy the VAR demand. The maximum correntropy criterion-based adaptive filter technique (AFT) is proposed to control the qZSI-STATCOM and to guarantee that the voltage at the SEIG terminal is harmonic-free while providing non-linear three-phase and single-phase loads.

The coordinated operation of the suggested voltage control and flywheel control systems ensures that load voltage and frequency are retained in their respective values at very low harmonic distortions regardless of wind speed and load variation. The simulation and experimental studies are carried out under different load conditions to validate the efficiencies of the PV-assisted STATCOM.

To improve system stability and minimize total costs, extra load current sensors can also be avoided. This paper proposes to control the SEIG terminal voltage and harmonic elimination in the standalone WECS systems using maximum correntropy criterion-based AFT with a fuzzy logic controller.

This paper aims to present a study on stability analysis of Jeffrey fluids in the presence of emergent chemical gradients within microbial systems of anisotropic porous media.

This study uses an effective method that combines non-dimensionalization, normal mode analysis and linear stability analysis to examine the stability of Jeffrey fluids in the presence of emergent chemical gradients inside microbial systems in anisotropic porous media. The study focuses on determining critical values and understanding how temperature gradients, concentration gradients and chemical reactions influence the onset of bioconvection patterns. Mathematical transformations and analytical approaches are used to investigate the system’s complicated dynamics and the interaction of numerous characteristics that influence stability.

The analysis is performed using the Jeffrey-Darcy type and Boussinesq estimation. The process involves using non-dimensionalization, using the normal mode approach and conducting linear stability analysis to convert the field equations into ordinary differential equations. The conventional thermal Rayleigh Darcy number RDa,c is derived as a comprehensive function of various parameters, and it remains unaffected by the bio convection Lewis number Łe. Indeed, elevating the values of ζ and γ′ in the interval of 0 to 1 has been noted to expedite the formation of bioconvection patterns while concurrently expanding the dimensions of convective cells. The purpose of this investigation is to learn how the temperature gradient affects the concentration gradient and, in turn, the stability and initiation of bioconvection by taking the Soret effect into the equation. The results provide insightful understandings of the intricate dynamics of fluid systems affected by chemical and biological elements, providing possibilities for possible industrial and biological process applications. The findings illustrate that augmenting both microbe concentration and the bioconvection Péclet number results in an unstable system. In this study, the experimental Rayleigh number RDa,c was determined to be 4π2at the critical wave number ( δcˇ) of π.

The study’s novelty originated from its investigation of a novel and complicated system incorporating Jeffrey fluids, emergent chemical gradients and anisotropic porous media, as well as the use of mathematical and analytical approaches to explore the system’s stability and dynamics.

Even though use studies of card catalogues are quite rare, use of online public access catalogues (OPACs) has been extensively investigated since early 1980s. Yet there are not many attempts to conduct comparative studies highlighting the differences in use of card catalogues and OPACs of the same library and user population. This paper reports an attempt made to study use of the OPAC of ISRO Satellite Centre (ISAC) library and compare the results with the findings of the study of use of card catalogue of the same library conducted 17 years ago. The paper not only brings various aspects of user behaviour about OPAC but also depicts the differences in user behaviour as well as the effects of technological changes from card catalogue (manual system) to OPAC (automated system).

This paper draws on data from a comparative study of use of the online public access catalogue (OPAC) and the card catalogue of the ISRO Satellite Centre (ISAC) library, and examines the steady decline in the use of subject searching by end‐users and the associated problems and issues. It presents data to highlight the negligible use of Boolean operators and combination searches, variations in descriptors assigned to books of the same class numbers, and too many records tagged to very broad descriptors. The article concludes that moving from a traditional card catalogue to a modern OPAC has not made subject searching more attractive or effective.

The purpose of this paper is to identify coronavirus contact using internet of things. The disease is said to be highly contagious with the contact of infected persons. Feared to be air-borne, droplets of body fluids can transmit the disease in a matter of hours. The predominant symptoms of the COVID-19 are high fever, cough, breathing problem, etc. Recent studies have demonstrated the evolution of the disease to hide its symptoms. As it is highly transmissible, this disease might spread at an exponential rate costing the lives of thousands of people. The chain of transmission has to be detected with utmost priority through early detection and isolation of infected people. Automated internet of things (IoT) devices can be used in design and implementation of a prediction scheme for reporting the health-care risks of the patients with various parameters such as temperature, humidity and blood pressure.

IoT is a configuration of multiple autonomous and embedded wireless devices for serving a purpose. Every object possesses an individual identity and will serve to register critical events as entries for future learning and decisions. IoT plays an inevitable role in medical industries, detection of vital signs of diseases and monitoring. Among other life-threatening diseases, a new pandemic is on rise among world nations. COVID-19, a novel severe acute respiratory syndrome virus originated from animals in December 2019 and is becoming a serious menace to Governments, despite serious measures of lockdowns.

In this paper, the authors defined an architecture of an IoT system to predict the Covid-19 disease by getting the data from the human through sensors and send the data to the doctor using mobile, computer, etc. The main goal is early health surveillance by predicting COVID-19. Accordingly, the authors are able to identify both symptomatic and asymptomatic patients, which will help in the early prediction of disease.

Using the proposed method, the authors can save the time of both patient and doctor by ensuring timely medical treatment and contribute toward breaking the transmission chain. In so doing, the method also contributes toward avoiding unnecessary expenses and saving human lives.

This study investigates the impact of corporate social responsibility (CSR) on corporate innovation. We selected the listed nonfinancial firms of South Asian Economies. The sample of the study comprised a total of 426 listed manufacturing firms of South Asian Countries for period spans 10 years from 2012 to 2021. In this study, descriptive statistics, multicollinearity diagnostic tests, correlation analysis and two-step dynamic panel system generalized method of moments (GMM) were applied to analyze the data. CSR measured with three proxies' social indicators, environmental indicators, and CSR composite index of social and environmental indicators. However, corporate innovation is captured with number of citations received in a year and number of patents filed in the year. Overall, findings of the study using all measures of CSR shows that CSR significantly and positively related with corporate innovation. Our results find support for CSR-innovation view with all measures of CSR. The findings suggest that the current study is helpful for managers, regulators, policymakers, and researchers. For managers, the study helps them to make the CSR and innovation decision. The policymakers should take appropriate innovative decision while considering factors such as CSR. This study can also be extended by considering this study for developed and emerging economies sample.

The aim of this study is to examine the impact of foreign direct investment (FDI) inflow and information and communication technology (ICT) on the economic performance of India by analysing annual data from 1991 to 2019.

This study has used data collected from secondary sources. The variables considered for the analysis are based on the review of theoretical and empirical literature. Moreover, apart from the quantitative variables, two qualitative variables have also been considered through the use of dummy variables. The Cobb–Douglas, Transcendental logarithmic and Simultaneous equations models have been used for the study.

The result reveals that the partial elasticities of the per-capita gross domestic product (PCGDP) of India with respect to FDI, mobile density (MD) and internet density (ID) are 0.074, 0.024 and 0.036, respectively. The positive and significant coefficient of the interaction among FDI, MD and ID in the estimation of the transcendental logarithmic function indicates the importance of ICT infrastructure in extracting the best out of FDI (the coefficient is 0.011 for the model without any control variables and it is 0.005 with control variables).

The findings of this study are more reliable as the latest available data have been analysed through the appropriate econometric models. This study will be useful for the policymakers in the formulation of policies with regard to foreign capital and digitalisation.