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The paper aims to test the spectral line-based weighted sum of gray gases (SLW) method in axisymmetric geometries with particles and high temperature gradients.

An SLW model is coupled with Trivic’s mean wavelength approach to estimate the radiative heat fluxes at the wall of an enclosure and to the base wall of the rocket exhaust, thereby subsequently studying the effect of concentration variation of the gases and particles in these cases. Radiative transfer equation is solved using modified discrete ordinates method. Anisotropic scattering is modeled using transport approximation.

Two cases considered show the importance of particle emission and scattering in the rocket plume base heating problems. In cases involving only gases, the concentration of H₂O tends to have more impact on the flux values than any other gas.

A full model of gases with particles in an axially varying temperature field is reported. Such cases are very common in practical applications. The present methodology gives more insight and a firm handle on the problem vis-a-vis other traditional techniques.

The purpose of this paper is to explore the mediating role of demonetisation in the usage of IT-enabled banking services (ITeBS). The study extends the theory of technology readiness (TR) (Parasuraman and Colby, 2015) by incorporating the behavioural intention and actual usage of ITeBS.

Based on the theory of TR and encompassing the impact of demonetisation, the study examines the functional relationship of TR, behavioural intention and actual usage. Structural equation modelling and mediation analysis are applied on a data set of 474 usable responses.

The study confirms that TR is a significant factor in customer’s intention to use ITeBS. The demonetisation variable fully mediates the relationship model, which implies a significant finding in the consumer acceptance literature.

The result of this study proposes three major implications. Primarily, the banks should focus on providing simple and user-friendly ITeBS interface and its uninterrupted access. It is necessary to educate the customers by giving them a trial of the service. Furthermore, social media platforms may be utilised as an effective and efficient tool to resolve customer complaints.

This study is first of the attempts to investigate government’s digital push in the technology adoption literature. The results indicate significant influence of demonetisation on the usage of ITeBS.

This paper presents the heat transfer enhancement from discrete heat sources using a wavy channel.

The finite element method is utilized to solve the hydrodynamic/thermal problem. The considered geometry consists of a channel formed by two wavy plates with six discrete heat sources placed on upper and lower walls. The global objective is to maximize the heat transfer from the heat sources. The wavy channel enhances heat transfer from the heat sources through the modification of the flow pattern in the channel. The effects of the Reynolds number, Prandtl number, waviness of the wavy wall, and the location of the heat sources on the thermal characteristics of the flow are investigated.

Results indicate that the wavy channel significantly enhances the heat flow out of the heat sources, with heat sources located at the minimum channel cross sections having the best performance. The Nusselt number increases with an increase in Reynolds number and waviness of the wavy channel. The higher Prandtl number has a positive effect on the heat flow out of the heat sources. The heat transfer enhancement can reaches as high as 120 percent for high Reynolds numbers and waviness of the channel.

The combination of wavy plates and optimum placement of heat sources can lead to better, less expensive thermal management of heat sources in electronic devices.

The purpose of this paper is to examine the impact of key antecedents of unified theory of acceptance and use of technology model 2 on behavioral intention to accept and use mobile payment systems in National Capital Region, India.

A sample of 267 mobile payment system users in National Capital Region was obtained through an online survey. A partial least squares method was used to find out whether key antecedents of UTAUT2 predict behavioral intention to accept mobile payment systems which further predicts use behavior toward mobile payment systems.

The research substantiates that performance expectancy, effort expectancy, habit and facilitating conditions significantly predict behavioral intention, which in turn significantly predict use behavior to use mobile payment systems. Both social influence and hedonic motivation were weak predictors of behavioral intention.

The research substantiates that performance expectancy, effort expectancy, habit and facilitating conditions significantly predict behavioral intention, which in turn significantly predict use behavior to use mobile payment systems. Both social influence and hedonic motivation were weak predictors of behavioral intention.

The research substantiates that performance expectancy, effort expectancy, habit and facilitating conditions significantly predict behavioral intention, which in turn significantly predict use behavior to use mobile payment systems. Both social influence and hedonic motivation were weak predictors of behavioral intention.

The purpose of this study is to develop a model that explains a user’s attitude toward M-payments in India, based on the motivational model and awareness about demonetization policy. The study also investigates the validity and differential predictive power of four different M-payment usage models, by considering the effect of improved awareness regarding demonetization policy on the core construct of the motivational model.

The model was tested with survey data from 362 M-payment users using partial least squares. Respondents were M-payment users with significant usage experience.

This study empirically determined that the motivation model and awareness about demonetization policy in M-payment usage after demonetization are connected. As hypothesized, the study found: a positive relationship between extrinsic motivation and intention to use M-payment, positive relationship between awareness about demonetization policy and behavioral intention to use M-payment, positive relationship between intrinsic motivation and extrinsic motivation, positive relationship between awareness about demonetization policy and extrinsic motivation and positive moderation effect of awareness about demonetization policy on the extrinsic motivation-behavioral intention relationships. The hypothesis that awareness about demonetization policy would have a moderating effect on intrinsic motivation–behavioral intention relationship was not supported.

From a practitioner’s perspective, this study underscores the importance of raising sufficient awareness about the demonetization policy as a determinant of users’ willingness to use M-payment services. Mandatory regulations by the government and motivation toward M-payment use can be a good starting point for a cashless economy.

This study makes a needed contribution to the literature by validating the integrated motivation model, emphasizing the importance of raising awareness about the demonetization policy among M-payment users. The model may provide a useful foundation for future research in this area.

This study proposed and tested three comprehensive models of the usage intention of proximity mobile payment services after a government regulation, by integrating the theory of planned behaviour (TPB) and the norm-activation model (NAM). The purpose of this paper is to investigate the effects of moral norms, merchant pro-activeness and perceived government regulation (demonetisation) on users’ continuance intention of proximity mobile payment services.

In total, 387 users of proximity mobile payment services in India were surveyed using a structured questionnaire. This study was carried out with shoppers in the Mumbai Metropolitan Region and New Delhi because of the diverse and large population of these cities.

The results of this study indicated that: integrating the variables of NAM into the original TPB model enhanced the prediction effect; perceived demonetisation regulation exerted a direct determinant effect as well as moderate effect on continuance usage intention of mobile payment services; also, extended TPB model with perceived demonetisation regulation as moderator could satisfactorily predict the continuance usage intention.

The results provided insightful evidence for the government and policymakers to outline more effective mandatory regulation policies.

This investigation attempts to enhance the theoretical understanding of the antecedents of in-store proximity mobile payment services after government regulation (demonetisation) in India.

This paper's aim is to investigate the effect of surface radiation on the developing laminar forced convection flow of a transparent gas between two vertical parallel plates. The walls are heated asymmetrically, this enhances the effect of radiation even with the two walls having low values of emissivity.

Numerical techniques were used to study the effect of the controlling parameters on wall temperatures, fluid temperature profiles, and Nusslet number.

The values of the radiation number at which surface radiation can engender symmetric heating (and hence maximum average Nusslet number on the heated wall and maximum reduction in the maximum heated wall temperature are achieved) are obtained. Threshold values of the radiation number at which radiation effects can be neglected are obtained.

Boundary‐layer flow model is used.

The implications include design of high‐temperature gas‐cooled heat exchangers, advanced energy conversion devices, advanced types of power plants, and many others.

Though a number of analyses of internal flows including radiation effect have been made, most have been directed at the simplest case of the prescribed uniform (isothermal) temperature boundary condition. The available literature that deals with the problem with prescribed heat flux at the walls is limited to fully developed flow or specifying the convection coefficient a priori. The lack of both theoretical and experimental data concerning combined forced convection and surface radiation developing flows between two parallel and its practical importance motivated the present work.

As data centres grow in size and complexity, traditional air-cooling methods are becoming less effective and more expensive. Immersion cooling, where servers are submerged in a dielectric fluid, has emerged as a promising alternative. Ensuring reliable operations in data centre applications requires the development of an effective control framework for immersion cooling systems, which necessitates the prediction of server temperature. While deep learning-based temperature prediction models have shown effectiveness, further enhancement is needed to improve their prediction accuracy. This study aims to develop a temperature prediction model using Long Short-Term Memory (LSTM) Networks based on recursive encoder-decoder architecture.

This paper explores the use of deep learning algorithms to predict the temperature of a heater in a two-phase immersion-cooled system using NOVEC 7100. The performance of recursive-long short-term memory-encoder-decoder (R-LSTM-ED), recursive-convolutional neural network-LSTM (R-CNN-LSTM) and R-LSTM approaches are compared using mean absolute error, root mean square error, mean absolute percentage error and coefficient of determination (R²) as performance metrics. The impact of window size, sampling period and noise within training data on the performance of the model is investigated.

The R-LSTM-ED consistently outperforms the R-LSTM model by 6%, 15.8% and 12.5%, and R-CNN-LSTM model by 4%, 11% and 12.3% in all forecast ranges of 10, 30 and 60 s, respectively, averaged across all the workloads considered in the study. The optimum sampling period based on the study is found to be 2 s and the window size to be 60 s. The performance of the model deteriorates significantly as the noise level reaches 10%.

The proposed models are currently trained on data collected from an experimental setup simulating data centre loads. Future research should seek to extend the applicability of the models by incorporating time series data from immersion-cooled servers.

The proposed multivariate-recursive-prediction models are trained and tested by using real Data Centre workload traces applied to the immersion-cooled system developed in the laboratory.

The interaction between mixed convection and thermal radiation in ventilated cavities with gray surfaces has been studied numerically using the Navier‐Stokes equations with the Boussinesq approximation. The effect of thermal radiation on streamlines and isotherms is shown for different values of the governing parameters namely, the Rayleigh number (10³ ≤ Ra ≤ 10⁶), the Reynolds number (50 ≤ Re ≤ 5000) and the surfaces emissivity (0 ≤ ε≤ 1). The geometrical parameters are the aspect ratio of the cavity A = L’/H’ = 2 and the relative height of the openings B = h’/H’ = 1/4. Results of the study show that thermal radiation alters significantly the temperature distribution, the flow fields and the heat transfer across the active walls of the cavities.

The aim of this work consists of studying numerically the coupling between natural convection and radiation in a tall rectangular cavity by examining the effect of the emissivity of the walls, ε, the Rayleigh number, Ra, and the inclination of the cavity, θ, on the flow characteristics and the existence ranges of the multiple solutions obtained.

The Navier‐Stokes equations were discretized by using a finite difference technique. The vorticity and energy equations were solved by the alternating direction implicit method. Values of the stream function were obtained by using the point successive over‐relaxation method. The calculation of the radiative heat exchange between the walls of the cavity is based on the radiosity method.

For an inclined cavity (θ=45°), up to four different solutions are obtained and their range of existence is found to be strongly dependent on the Rayleigh number and the emissivity of the cavity walls. In the case of a vertical cavity (θ=90°), the weak reduction of the convection effect due to radiation is largely compensated for by the contribution of the radiation which enhances the overall heat transfer through the cold surface of the cavity and favours the appearance of secondary cells.

The existence of multiple steady‐state solutions in an inclined cavity (θ=45°) and the number of the obtained solutions are affected by the presence of radiation. In face, the increase of the emissivity reduces the number of solutions for weak values of the Rayleigh number. Also, the increase of this parameter favours the multiplicity of solutions for all the considered values of the emissivity. For a vertical cavity (θ=90°), the effect of radiation generates an oscillatory convection for large values of the Rayleigh number.