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The purpose of this study is to investigate factors contributing to the development of resilience capacity and capability of industrial clusters in order for them to mitigate, absorb and adapt to the impacts of Iran’s economic sanctions.

The Hospital Equipment Cluster of Tehran (HECT) was selected as the case study for the research. The data were collected using the library and field research and analyzed using the thematic analysis method.

The key dimensions of resilience were grouped into socio-cultural, economic, technical-organizational and institutional–infrastructural categories. Based on the “complex adaptive system” theory, each of the abovementioned dimensions were investigated on different levels of analysis, including individual, enterprise, cluster, government and environment. Eventually, recommendations were made by considering required capacities and capabilities of resilience of the hospital equipment sector toward economic sanctions.

The resilience toward economic sanctions, as an extensive disaster, is a considerably new subject and few studies have been performed in the field. This research provides practical solutions for local policy-makers, authorities and enterprise managers.

The purpose of this study is to explore the impact of customer engagement in sales promotion on purchase intention. Utilizing value co-creation and customer engagement theories, the authors tested a model that specifies the effect of customer engagement in sales promotion on purchase intention, through its impact on perceived value and customer satisfaction.

The model was tested with the PLSc-SEM approach.

Engaging customers to store's offers by giving them the possibility to choose the type of promotional discount that suits their personal preferences and needs is positively associated with purchase intention, and that this relationship is mediated in serial by perceived value and customer satisfaction.

Involving customers in sales promotion provides opportunities for retail front line management, as well as for customer relationship management to attract attention and interest.

While previous research concerned situations where firms and customers collaborate in the co-creation of value, its role in the sales promotion process is yet unclear. This study starts filling this gap by taking a closer look at customer participation in the sales promotion process and its impact on customer purchase intention.

The purpose of this paper is to consider natural convection of a nanofluid inside of a C-shaped cavity using Lattice Boltzmann method (LBM).

Effects of some geometry and flow parameters consisting of the aspect ratio of the cavity, aspect ratio of the heat source; Rayleigh number (Ra = 10³ − 10⁶) have been investigated. The validity of the method is checked by comparing the present results with ones from the previously published work.

The results demonstrate that for Ra = 10³, the aspect ratio of the heat source has more influence on the average Nusselt number in contrast to the case of Ra = 10⁶. Contrary to the fact that the average Nusselt number increases non-linearly more than twice because of the increase of the aspect ratio of the enclosure at Ra = 10³, the average Nusselt number has a linear relation with the aspect ratio for of Ra = 10⁶. Therefore, upon increasing the Rayleigh number, the efficiency of the aspect ratio of the cavity on the thermal convection, gradually diminishes.

The authors believe that all the results, both numerical and asymptotic, are original and have not been published elsewhere.

This paper aims to study the natural convection of a nanofluid inside a cavity which contains obstacles using lattice Boltzmann method (LBM). The results have focused mainly on various parameters such as number and aspect ratio of roughness elements and different nanoparticle volume fraction. The isotherms and streamlines are presented to describe the hydrodynamics and thermal behaviors of the nanofluid flow throughout the enclosure.

The methodology of this paper consists of mathematical model, statement of the problem, nanofluid thermophysical properties, lattice Boltzmann method, LBM for fluid flow, LBM for heat transfer, numerical strategy, boundary conditions, Nusselt (Nu) number calculation, code validation and grid independence.

Natural convection heat transfers of a nanofluid inside cavities with and without rough elements have been studied. Lattice Boltzmann technique has been used as numerical approach. The results showed that at higher Rayleigh number (Ra = 10⁶), there are denser streamlines near the left (source) and right wall (sink) which results in better cooling and enhances convective heat rejection to the heat sink. After a distinctive aspect ratio of rough elements (A =0.1), change in streamline pattern which arises from increasing of aspect ratio does not have an important effect on isotherms. Results indicate that for lower Rayleigh number (Ra =10³), no variation in average Nu is observed with increasing in number of roughness, while for higher one (Ra = 10⁶) average Nu decreases from N = 0 (smooth cavity) up to N = 4 and then remains constant (N = 6).

Currently, no argumentative and comprehensive extraction can be concluded without fully understanding the role of different arrangement of roughness. Some geometrical parameters such as aspect ratio, number and position of rough elements have been considered. Also, the effect of nanoparticle concentration was studied at different Ra number. Briefly, using LBM, this paper aims to investigate the natural convection of a nanofluid flow on the thermal and hydrodynamics parameters in the presence of rough element with various arrangements.

The purpose of this paper is to numerically study MHD natural convection and entropy generation of Al₂O₃-water alumina nanofluid inside of T-shaped baffled cavity which is subjected to a magnetic field.

Effect of various geometrical, fluid and flow factors such as aspect ratio of enclosure and baffle length, Rayleigh and Hartmann number of nanofluid have been considered in detail. The hydrodynamics and thermal indexes of nanofluid have been described using streamlines, isotherms and isentropic lines.

It is found that by enhancing Hartmann number, symmetrical streamlines gradually lose symmetry and their values decline. It is found that by enhancing Hartmann number, symmetrical streamlines gradually lose symmetry and their values decline. The interesting finding is an increase in the impact of Hartmann number on heat transfer indexes with augmenting Rayleigh number. However, with augmenting Rayleigh number and, thus, strengthening the buoyant forces, the efficacy of Hartmann number one, an index indicating the simultaneous impact of natural heat transfer to entropy generation increases. It is clearly seen that the efficacy of nanofluid on increased Nusselt number enhances with increasing aspect ratio of the enclosure. Based on the results, the Nusselt number generally enhances with the larger baffle length in the enclosure. Finally, with larger Hartmann number and lesser Nusselt one, entropy production is reduced.

The authors believe that all the results, both numerical and asymptotic, are original and have not been published elsewhere.

The purpose of this paper is to propose and test an integrated model focusing on the drivers and consequences of intellectual capital in the context of the hotel industry.

A quantitative study was conducted, including 156 hotels located in Iran. Structural equation modeling examines the validity of constructs and path relationships.

The results of the PLS-SEM analysis provided three findings as follows: the three dimensions of social capital, namely the structural, relational, and cognitive social capital, had positive effects on knowledge sharing; knowledge sharing had positive effects on three components of intellectual capital (human capital, structural capital and relational capital); and intellectual capital dimensions, which in turn, lead to innovation.

The combination of a developing country context and the significance of social capital, knowledge sharing, intellectual capital and innovation in hotel industry enhance the contextual contribution of the paper.

There is limited research examining the relationship between social media and green food purchasing behaviour. In the current study, we examine the factors that affect consumers’ green food purchasing behaviour in Türkiye.

Data collected from the participants by survey method were analysed using Smart PLS 4.0 with IBM SPSS 26 and PLS to run SEM.

Our findings have revealed that from all the structural elements in the theory of planned behaviour (TPB), only attitude and perceived behavioural control contribute to consumers’ green food purchasing behaviour, while subjective norms do not contribute to consumers’ green food purchasing behaviour. Additionally, it was found that social media usage (SMU) and digital marketing interactions (DMI) have a positive and significant effect on green food purchasing behaviour. More information, experiences, opinions and recommendations on green foods in social media channels can encourage consumers to buy more green food.

This study first evaluates the applicability of the TPB model in explaining green food purchasing behaviour. This study is extended with two new factors included in the original framework of the TPB model, namely, SMU and DMI.

Using passive techniques like twisted tapes and corrugated surface is an efficient method of heat transfer improvement, since the referred manners break the boundary layer and improve the heat exchange. This paper aims to present an improved dual-flow parabolic trough collector (PTC). For this purpose, the effect of an absorber roof, a type of turbulator and a grooved absorber tube in the presence of nanofluid is investigated separately and simultaneously.

The FLUENT was used for solution of governing equation using control volume scheme. The control volume scheme has been used for solving the governing equations using the finite volume method. The standard k–e turbulence model has been chosen.

Fluid flow and heat transfer features, as friction factor, performance evaluation criteria (PEC) and Nusselt number have been calculated and analyzed. It is showed that absorber roof intensifies the heat transfer ratio in PTCs. Also, the combination of inserting the turbulator, outer corrugated and inner grooved absorber tube surface can enhance the PEC of PTCs considerably.

Results of the current study show that the PTC with two heat transfer fluids, outer and inner surface corrugated absorber tube, inserting the twisted tape and absorber roof have the maximum Nusselt number ratio equal to 5, and PEC higher than 2.5 between all proposed arrangements for investigated Reynolds numbers (from 10,000 to 20,000) and nanoparticles [Boehmite alumina (“λ-AlOOH)”] volume fractions (from 0.005 to 0.03). Maximum Nusselt number and PEC correspond to nanoparticle volume fraction and Reynolds number equal to 0.03 and 20,000, respectively. Besides, it was found that the performance evaluation criteria index values continuously grow by an intensification of nanoparticle volume concentrations.

Inclination angle has been reported to have an enhancing effect on the thermal-hydraulic characteristics and entropy of some thermal systems. Therefore, this paper aims to numerically investigate the effects of inclination angle, volume concentration and Reynolds number on the thermal and hydraulic characteristics and entropy generation rates of water-based Al₂O₃ nanofluids through a smooth circular aluminum pipe in a turbulent flow.

A constant heat flux of 2,000 Watts is applied to the circular surface of the tube. Reynolds number is varied between 4,000 and 20,000 for different volume concentrations of alumina nanoparticles of 0.5%, 1.0% and 2.0% for tube inclination angles of ±90o, ±60o, ±45o, ±30o and 0o, respectively. The simulation is performed in an ANSYS Fluent environment using the realizable kinetic energy–epsilon turbulent model.

Results show that +45o tube orientation possesses the largest thermal deviations of 0.006% for 0.5% and 1.0% vol. concentrations for Reynolds numbers 4,000 and 12,000. −45o gives a maximum pressure deviation of −0.06% for the same condition. The heat transfer coefficient and pressure drop give maximum deviations of −0.35% and −0.39%, respectively, for 2.0% vol. concentration for Reynolds number of 20,000 and angle ±90o. A 95%–99.8% and 95%–98% increase in the heat transfer and total entropy generation rates, respectively, is observed for 2.0% volume concentration as tube orientation changes from the horizontal position upward or downward.

Research investigating the effect of inclination angle on thermal-hydraulic performance and entropy generation rates in-tube turbulent flow of nanofluid is very scarce in the literature.

This paper aims to peruse the influence of second law analysis for electrically conducting fluid of a Casson nanofluid over a wedge. For activation energy, a modified Arrhenius function is used.

The highly non-linear governing equations are developed using similarity transformations and then computed numerically via Keller–Box method.

The influences of emerging parameters on velocity, temperature distribution and concentration of nanoparticle are explained and presented via graphs and tables. Also, the behavior of fluid flow is investigated through the coefficient of skin friction, Nusselt and Sherwood numbers. Results reveal that the velocity profile enhances due to increasing Casson parameter and magnetic parameter, whereas the temperature distribution and concentration of nanoparticle decrease with larger vales of Casson parameter. It is inspected that the concentration boundary layer increases due to activation energy and decreases due to reaction rate and temperature differences.

The authors believe that all the numerical results are original and significant which are used in biomedicine, industrial, electronics and transportation. The results have not been considered elsewhere.