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This study aims to numerically analyse the impact of an inclined magnetic field and Joule heating on the conjugate heat transfer because of the mixed convection of an Al₂O₃–water nanofluid in a thick wall enclosure.

A horizontal temperature gradient together with the shear-driven Flow creates the mixed convection inside the enclosure. The nonhomogeneous model, in which the nanoparticles have a slip velocity because of thermophoresis and Brownian diffusion, is adopted in the present study. The thermal performance is evaluated by determining the entropy generation, which includes the contribution because of magnetic field. A control volume method over a staggered grid arrangement is adopted to compute the governing equations.

The Lorentz force created by the applied magnetic field has an adverse effect on the flow and thermal field, and consequently, the heat transfer and entropy generation attenuate because of the presence of magnetic force. The Joule heating enhances the fluid temperature but attenuates the heat transfer. The impact of the magnetic field diminishes as the angle of inclination of the magnetic field is increased, and it manifests as the volume fraction of nanoparticles is increased. Addition of nanoparticles enhances both the heat transfer and entropy generation compared to the clear fluid with enhancement in entropy generation higher than the rate by which the heat transfer augments. The average Bejan number and mixing-cup temperature are evaluated to analyse the thermodynamic characteristics of the nanofluid.

This literature survey suggests that the impact of an inclined magnetic field and Joule heating on conjugate heat transfer based on a two-phase model has not been addressed before. The impact of the relative slip velocity of nanoparticles diminishes as the magnetic field becomes stronger.

Nanofluids’ properties made them interesting for various areas like engineering, medicine or cosmetology. Discussed here, research pertains to specific problem of heat transfer enhancement with application of the magnetic field. The main idea was to transfer high heat rates with utilization of nanofluids including metallic non-ferrous particles. The expectation was based on changed nanofluid properties. However, the results of experimental analysis did not meet it. The heat transfer effect was smaller than in the case of base fluid. The only way to understand the process was to involve the computational fluid dynamics, which could help to clarify this issue. The purpose of this research is deep understanding of the external magnetic field effect on the nanofluids heat transfer.

In presented experimental and numerical studies, the water and silver nanofluids were considered. From the numerical point of view, three approaches to model the nanofluid in the strong magnetic field were used: single-phase Euler, Euler–Euler and Euler–Lagrange. In two-phase approach, the momentum transfer equations for individual phases were coupled through the interphase momentum transfer term expressing the volume force exerted by one phase on the second one.

Therefore, the results of numerical simulation predicted decrease of convection heat transfer for nanofluid with respect to pure water, which agreed with the experimental results. The experimental and numerical results are in good agreement with each other, which confirms the right choice of two-phase approach in analysis of nanofluid thermo-magnetic convection.

The Euler–Lagrange exhibit the best matching with the experimental results.

The purpose of this paper is to investigate the effect of pulsed magnetic field (PMF) with different duty cycles on the melt flow and heat transfer behaviors during direct-chill (DC) casting of large-size magnesium alloy billet and find the appropriate range of duty cycle.

A transient two-dimensional mathematical model coupled electromagnetic field, flow field and thermal field, is conducted to study the melt flow and temperature field under PMF and compared with that under the harmonic magnetic field.

The results reveal that melt vibration and fluctuation are generated due to the instantaneous impact of repeated thrust and pull effects of Lorentz force under PMF. The peak of Lorentz force decreases greatly with the increasing duty cycle, but the melt fluctuation region is expanded with higher duty cycle, which accelerates the interior melt velocity and reduces the temperature gradient at the liquid-solid interface. However, PMF with overly high duty cycle has adverse effect on the melt convection and limited influence on the interior melt. A duty cycle of 20% to 50% is a reasonable range.

This paper can provide guiding significance for the setting of duty cycle parameters on DC casting under PMF.

There are few reports on the effect of PMF parameters during DC casting with applying PMF, especially for duty cycle, a parameter unique to PMF. The findings will be helpful for applying the external field of PMF on DC casting.

This study aims to develop two piezoelectric textile devices formed from different weft knitted fabric rapports (Jersey and Pique) to be applied in the renewable energy’s (RE) area.

Two different weft knitted rapports were produced with polyester (PES). The device developed has five layers: a central of poly(vinylidene fluoride) (PVDF) nonwoven, involved by two insulating layers of PES knitted fabric; and two conductive external layers, made of polypyrrole-coated PES knitted fabric. The piezoelectric textile devices were joined by sewing the five layers of the device.

The FTIR technique confirmed the β-phase in the PVDF nonwoven. This study produced and tested two different textiles devices with piezoelectric behavior, confirmed by the correlated pattern of voltage and tensile stress difference curves, showing the potential application in RE’s and sustainable energies field as smart textiles, such as devices incorporated in garments in the areas of high movement (elbow, knee, foot, fingers and hands, among others), and as an energy generator device

Textile materials with piezoelectric properties promise to advance RE’s developments due to their high material flexibility and sensitivity to the electrical response. The knitted fabric technology presents flexibility due to its construction process. Comparative studies analyzing the electrical response between knitted and woven fabrics have already been realized. However, there is a gap in terms of research scientific research regarding the comparison of the piezoelectric effect in a material that presents different knitted fabric rapports.

Due to an increase in energy demands, it has become vital to devise efficient energy policies. Literature has suggested multiple factors influencing the consumption of specific energy types. Among others, institutional quality (INQ) is another factor that can determine energy consumption. Given this, the current study aimed to investigate the impact of INQ on fossil fuel energy (FFE) and renewable energy consumption (REC).

The empirical analysis was conducted on 20 years (2000–2019) of data from South Asian economies, and regression among variables was established by employing the dynamic ordinary least square and fully modified ordinary least square models. The selection of both techniques is subject to the existence of cointegration identified by the Johansen cointegration test. Other pre-estimation techniques include cross-section dependence and unit root testing validating the estimation of coefficients in the long run.

The analysis mainly reveals the negative impact of INQ on FFE and the positive impact of INQ on REC. The authors further find the asymmetric impact of control variables including foreign direct investment inflow, economic growth, inflation rate, financial sector development and energy investment on the consumption of both types of energy.

Given the positive influence of INQ on REC, it is recommended to focus on improving the efficiency of institutions specifically those that are directly linked with energy-related policies. A better INQ can ensure environmental sustainability by enhancing the consumption of renewable energy. Therefore, it is advised to exert more efforts to improve the INQ.

In view of the positive influence of INQ on REC, it is recommended to focus on improving the efficiency of institutions specifically that are directly linked with energy-related policies. A better INQ can ensure environmental sustainability by enhancing the consumption of renewable energy. Therefore, it is advised to exert more efforts for improving the INQ.

This study offers robustness to the empirical findings of existing literature on the INQ-REC nexus and complements the underdeveloped literature on the INQ-FFE relationship.

This study aims to investigate the influence of the interrelationship between the deployment of Industry 4.0 (I4.0) technologies and the application of lean production (LP) practices on the degree of organizational sustainability performance (SP) enhancement of the Bangladeshi ready-made garment (RMG) sector.

Previously, researchers have applied the resource-based view (RBV) or dynamic capability view (DCV) to describe the interaction of resources and capacities (technologies, management practices, SP) to analyze their effectiveness. However, in light of several contemporary academic discussions, this study contends that these organizational views are inappropriate for explicating SP. Hence, as the foundation of this study’s theoretical framework, the authors used the practice-based view (PBV), which is recommended as a useful window to evaluate the function of practices that are common and simple to emulate in execution. To test the theoretical framework and research hypothesis, this study used partial least square (PLS) analysis. For that, the authors carried out a systematic survey to collect data from 80 Bangladeshi RMG factories.

The results of this research imply that LP is a crucial factor in enhancing organizational SP. Moreover, the results also indicate that the adoption of I4.0 technologies along with LP can assist in delivering the lean objectives more efficiently and, therefore, the combined application of LP practices and I4.0 technologies play a significant role in enhancing organizational SP.

Though the present literature indicates the probable significant association between LP and SP or I4.0 technologies and SP, no study, with the best of the authors’ knowledge, has empirically examined the combined impacts of correlation between LP and I4.0 on SP. This is also a unique study to apply the PBV theory to explain the organizational SP through the combination of common resources and technologies.

Using the theoretical lens of appraisal theory, this research aims to investigate the interrelationship between employees' organizational justice perceptions and counterproductive work behaviours (CWBs) through the mediation of negative emotions.

To this end, a sample comprised of 207 banking sector employees of Pakistan was utilized to test hypothesized relationships. The collected data were analyzed through the partial least structural equation modelling technique.

Results show that counterwork behaviours are influenced by distributive and procedural justice perceptions. The mediating effects of negative emotions were also statistically significant between procedural, interpersonal and informational justice perceptions and counterwork behaviours. No gender differences were found between distributive, interpersonal and informational justice perceptions and counterwork behaviours. However, the authors found that procedural justice perceptions of female employees are strongly related to CWBs as compared to male employees.

This research contributes to the existing organizational behaviour literature by empirically testing the hypothesized relationships using the theoretical lens of appraisal theory with advanced quantitative data analysis techniques.

The purpose of this study is to investigate the impact of the oscillatory movement on heat transfer within a double periodic lid-driven cubic enclosure filled with copper-water nanofluid and to figure out how the oscillations impact the fluid flow and thermal behavior inside the enclosure. The authors asserted that this study will help to improve the heat transfer efficiency and the thermal performance of various technical engineering equipments.

The cubic enclosure is heated differentially; the left side is cold, the right one is warm and the remaining walls are insulated. Based on the movement directions of the upper and bottom lids, two cases for lid-driven walls are examined (Case 1: same movement for both lids; Case 2: opposite movement for the lids). The finite volume approach was implemented to solve the time-dependent three-dimensional momentum and energy equations, adopting the power low as a scheme of resolution. The numerical study was carried out for a range of parameters: volume fraction (0 ≤ φ ≤ 0.06), Richardson number (0.1 ≤ Ri ≤ 10), non-dimensional lid frequency (2π/50 ≤ Ω ≤ 2π/10) and fixed Grashof number 105.

The numerical simulations were executed for two different cases of the direction of the motion of the oscillatory lids. Based on the findings obtained, decreasing the Richardson number with low lids frequency gives the best heat transfer enhancement for both cases. Furthermore, in the same conditions, swapping from Case 2 to Case 1 leads to enhancing the maximum average Nusselt number obtained by 29.74%. At a high Richardson number, using high lids frequency increases the heat transfer rate compared to using low lids frequency (an enhancement of 4.32% for Case 1 and 3.63% for Case 2). The best heat transfer rate was established for Case 1 when the lids move positively, transporting the cold flow to the hot side. In all cases, increasing the concentration of nanoparticles improves the heat transfer.

The current study gives an understanding of the problem of mixed convection in a cubic enclosure with oscillatory walls, which has received little attention. And also, there has been no study published on unsteady mixed convection within a double oscillatory lid-driven cavity.

A viable framework has been proven to reduce operational and institutional inefficiencies in the urban water supply sector. The absence of drivers necessary to develop a framework may have hindered institutional development and effective Ghanaian urban water supply management. Thus, the research aims to identify the drivers and develop a framework for effectively managing the urban water supply in Ghana.

The study utilised a qualitative research design approach and analysed collected data to proffer answers to the research questions. The research sampled 19 participants, and saturation was achieved.

Findings identified drivers for developing Ghana's urban water supply framework. They categorised them into the availability of water supply resources, the level of professionalism of the personnel, the provision of accessible quality water, the efficient management system of water supply, prudent financial management, ethics for managing water supply and the culture of managing water supply. These pertinent constructs form components of Ghana's urban water sector framework.

Besides supporting transformation and sustainability to develop a framework for managing Ghana's urban water supply sector, policymakers may utilise the developed model to evaluate public urban water supply compliance with Ghana's water sector performance.

The purpose of this study is to adopt the upper echelon theory to analyze the effect of chief executive officer (CEO) transformational leadership on organizational ethical culture and its subsequent impact on firm performance. The study also integrates the knowledge from the structure–conduct–performance paradigm to test whether the high degree of competitive intensity that firms experience could weaken the effect of organizational ethical culture on firm performance.

Online survey data were obtained from firms in Thailand that were randomly selected from the directory provided by the Department of Business Development (n = 200). Partial least squares structural equation modeling was used to analyze the data.

Organizational ethical culture significantly meditates the effect of CEO transformational leadership on firm performance. Moreover, the moderating effect analysis illustrates that the positive effect of organizational ethical culture on firm performance tends to be lower when firms have a high level of competitive intensity in the market.

Overall, this study adds new knowledge to the literature by showing that, although ethical culture created by transformational leaders can lead to high firm performance, the market environment in terms of competitive intensity could mitigate this benefit.