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The macroscopic properties of dried sand can be correctly modelled when the accurate determination of the microscopic properties is available. The microscopic properties between the particles such as the coefficients of rolling (µ _r) and sliding (µ _s), are numerically determined in two different ways: with and without considering the fluid effect. In an earlier study, the microscopic properties were determined by discrete element method (DEM) and without considering the air effect on the macroscopic properties such as the Angle of Repose. The purpose of this paper is to recalibrate the microscopic properties through a coupling between the DEM and computational fluid dynamics (CFD).

The first step is dedicated to the calibration of the CFD-DEM model through modelling a single particle sedimentation within air, water, and silicon oil. The voidage and drag models, the grid size ratio (D/dx), the domain size ratio (W/D), and the optimum coupling interval between the CFD and DEM were investigated through comparing the CFD-DEM results with the analytical solution and experimental data. The next step is about modelling an Hourglass with the calibrated CFD-DEM model to recalibrate the µ _r and µ _s of dried sand particles.

It was concluded that the air has a minor effect on the macroscopic properties of the dried sand and the µ _r and µ _s that were obtained with the DEM can be utilized in the CFD-DEM simulation.

Utilizing the granulometry of dried quartz sand in the calibration process of the CFD-DEM method has raised the possibility of using the µ _r and µ _s for other applications in future studies.

The global call to ‘leave-no-one behind’ cannot be achieved without tacking the intractable social issues faced by the most excluded people. There is increasing interest in using visual methodologies for participatory research in contexts of marginalisation, because they offer the potential to generate knowledge from people’s lived experience, which can reveal subjective, emotional, and contextual aspects missed by other methods; alongside the means for action through showing outputs to external audiences. The challenge is that the perspectives of those in highly inequitable and unaccountable contexts are – by definition – rarely articulated and often neglected. The author thus begins by assuming that there are unavoidable tensions in using visual methods; between perpetuating marginalisation by inaction, which is ethically questionable; and the necessary risks in bringing unheard views to public attention. Many experienced practitioners have called for a situated approach to visual methods ethics (Clark, Prosser, & Wiles, 2010; Gubrium, Hill, & Flicker 2014; Shaw, 2016). What is less clear is what this means for those wanting to apply this practically. In this chapter, the author addresses this gap through the exemplar of participatory video with marginalised groups. Drawing on cases from Kenya, India, Egypt, and South Africa, the author contributes a range of tried-and-tested strategies for navigating the biggest concerns such as informing consent; and the tensions between respecting autonomy and building inclusion, and between anonymity and supporting participant’s expressive agency. Through this, the author provides a resource for researchers, including prompts for critical reflection about how to generate solutions to visual ethical dilemmas in context.

Historical bazaars, a huge treasure of Iranian culture, art and economy, are places for social capital development. Un-supervised management in past decades has led to the demolition and change of historical bazaars and negligence of its different aspects. The present research aims to investigate the resilience of historical bazaars preserving their identity and different developments.

The artificial neural network (ANN) has been applied to investigate the resilience of historical bazaars. This model consists of three main networks for evaluating the resilience of historical networks in terms of adaptability, variability and reactivity.

The ANN proposed to evaluate the resilience of historic bazaars based on the mentioned factors is efficient. By calculating mean squared error (MSE), the model accuracy for evaluating adaptability, variability and reactivity were obtained at 7.62e-25, 2.91e-24 and 1.51e-24. The correlation coefficient was obtained at a significance level of 99%. This indicates the considerable effectiveness of the artificial intelligence model in modeling and predicting the qualitative properties of historical bazaars resilience.

This paper clarifies indexes and components of resilience in terms of adaptability, variability and reactivity. Then, the ANN model is obtained with the least error and very high accuracy that predict the resilience of historical bazaars.

Contact centers (CCs) are one of the main touch points of customers in an organization. They form one of the inputs to customer relationship management (CRM) to enable an organization to efficiently resolve customer queries. CCs have an important impact on customer satisfaction and are a strategic asset for CRM systems. The purpose of this paper is to review the current literature on CCs and identify their shortcomings to be addressed in the current digital age.

The current literature on CCs can be classified into the analytical and the managerial aspects of CCs. In the former, data mining, text mining, and voice recognition techniques are discussed, and in the latter, staff training, CC performance, and outsourced CCs are discussed.

With the growth of information and communication technologies, the information that CCs must handle both in terms of type and volume, has changed. To deal with such changes, CCs need to evolve in terms of their operation and public relations. The authors present a state-of-the-art review of the challenges in identifying the gaps in order to have the next generation of CCs. Lack of an interactive CC and lack of data integrity for CCs are highlighted as important issues that need to be dealt with properly by CCs.

As far as the authors know, this is the first paper that reviews CCs’ literature by providing the comprehensive survey, critical evaluation, and future research.

Aiming at the problems of poor accuracy and limitation in strength assessment of spot welding vehicle body caused by uncertain factors, such as key component size and nugget diameter, the numerical models of strength uncertainty analysis of spot-welded joints were constructed based on evidence theory and fuzzy theory.

Evidence theory and fuzzy theory are used to deal with the uncertainty of design parameter, and differential evolution algorithms are used to calculate the propagation process of uncertainty in this model. Furthermore, efficient relationship between the strength of welded joints and each design parameter is constructed by using response surface proxy model, which effectively avoids the problem of repeated complex finite element analysis in uncertainty analysis.

The results show that the constructed uncertainty numerical model is effective for the multiple uncertainties and give interval results under different probabilities and affiliations, which can more effectively evaluate the strength of the welded body structure to avoid overly conservative estimates for deterministic design.

The evidence theory is improved and combined with differential evolution algorithm and response surface method to effectively improve the computational efficiency. Based on the improved evidence theory and fuzzy algorithm, the numerical models for the uncertainty analysis of solder joint strength of welded structures are constructed and their feasibility is verified.

Knowledge is a fundamental source for sustainability and transfer as it plays a vital role in gaining and maintaining competitive advantage; thus it is imperative to investigate the factors that might impact knowledge transfer (KT). Therefore, the purpose of this paper is to investigate the association between knowledge enablers (organizational culture (OC), information technology (IT) knowledge leadership (KL) and knowledge strategy (KS)) and KT in the Jordanian construction industry.

A quantitative research approach was adopted, and structured questionnaire was sent to the employees in the construction industry. An aggregate of 250 surveys were distributed and out of them 195 were obtained, which represented a response rate of 78 percent.

The results of this paper showed that KS, OC, IT and KL has positive and significant impact on KT.

The study contributes to the literature by empirically testing the antecedents of KT in the Jordanian construction industry. To the best of authors’ knowledge, there are not many studies that incorporate these factors in single model, especially in Jordan.

This research aims to investigate and identify knowledge transfer (KT) enablers within the developing country of Ghana. These enablers act as mechanisms to stimulate knowledge creation, knowledge protection and build effective knowledge-sharing (KS) behaviour in construction companies – consequently, they are crucial to business survival in a globally competitive market.

A perception questionnaire survey was used to elicit responses from construction practitioners using purposive and snowballing non-probability sampling techniques. Summary statistical analysis and a chi-square test was used to uncover relationships between the independent and dependent variables.

An empirical examination of data collected indicated that knowledge strategy, organizational culture, information technology and knowledge leadership as knowledge enablers have a significant positive relationship with KT. Future research is however required to measure transfer within an organization vis-à-vis measure perception of such.

The work presents a rare glimpse of the relationship between knowledge enablers and KT (particularly in a developing country context) and as such provides utility to policymakers and construction firms to enhance their knowledge capabilities.

The purpose of this study is three-dimensional flow and heat transfer investigation of water/Al₂O₃ nanofluid inside a microchannel with different cross-sections in two-phase mode.

The effect of microchannel walls geometry (trapezoidal, sinusoidal and stepped microchannels) on flow characteristics and also changing circular cross section to trapezoidal cross section in laminar flow at Reynolds numbers of 50, 100, 300 and 600 were investigated. In this study, two-phase water/Al₂O₃ nanofluid is simulated by the mixture model, and the effect of volume fraction of nanoparticles on performance evaluation criterion (PEC) is studied. The accuracy of obtained results was compared with the experimental and numerical results of other similar papers.

Results show that in flow at lower Reynolds numbers, sinusoidal walls create a pressure drop in pure water flow which improves heat transfer to obtain PEC < 1. However, in sinusoidal and stepped microchannel with higher Reynolds numbers, PEC > 1. Results showed that the stepped microchannel had higher pressure drop, better thermal performance and higher PEC than other microchannels.

Review of previous studies showed that existing papers have not compared and investigated nanofluid in a two-phase mode in inhomogeneous circular, stepped and sinusoidal cross and trapezoidal cross-sections by considering the effect of changing channel shape, which is the aim of the present paper.

Increasing heat transfer rate in spiral heat exchangers is possible by using conventional methods such as increasing number of fluid passes and counter flowing. In addition, newer ideas such as using pillows as baffles in the path of cold and hot fluids and using nanofluids can increase heat transfer rate. The purpose of this study is to simulate turbulent flow and heat transfer of two-phase water-silver nanofluid with 0-6 Vol.% nanoparticle concentration in a 180° path of spiral heat exchanger with elliptic pillows.

In this simulation, the finite volume method and two-phase mixture model are used. The walls are subjected to constant heat flux of q″ = 150,000 Wm⁻². The inlet fluid enters curves path of spiral heat exchanger with uniform temperature T_in = 300 K. After flowing past the pillows and traversing the curved route, the working fluid exchanges heat with hot walls and then exits from the section. In this study, the effect of radiation is disregarded because of low temperature range. Also, temperature jump and velocity slipping are disregarded. The effects of thermophoresis and turbulent diffusion on nanofluid heat transfer are disregarded. By using finite volume method and two-phase mixture model, simulations are performed.

The results show that the flow and heat transfer characteristics are dependent on the height of pillows, nanoparticle concentration and Reynolds number. Increasing Reynolds number, nanoparticle concentration and pillow height causes an increase in Nusselt number, pressure drop and pumping power.

Turbulent flow and heat transfer of two-phase water-silver nanofluid of 0-6 per cent volume fraction in a 180° path of spiral heat exchanger with elliptic pillows is simulated.

The purpose of this paper is to numerically simulate the nanofluid boiling inside a tube in turbulent flow regime and to investigate the effect of adding volume faction of CuO nanoparticles on the boiling process.

To make sure the accuracy of the obtained numerical results, the results of this paper have been compared with the experimental results and an acceptable coincidence has been achieved. In the current paper, by Euler–Euler method, the phase change of boiling phenomenon has been modeled. The presented results are the local Nusselt number distribution, temperature distribution of wall, the distribution of volume fraction of vapor phase and fluid temperature at the center of the tube.

The obtained results indicate that using nanofluid is very effective in the postponement of the boiling process. Hence, by change the amount of volume fraction of nanoparticles in base fluid, the location of phase change and bubble creation are changed. Also, at the Reynolds numbers of 50,000, 100,000 and 150,000 with the volume fraction of 2 per cent, the beginning locations of phase change process are, respectively, 2D, 10D and 13D, and for the volume fraction of 4 per cent, the beginning locations of phase change are 4D, 18D and 19D, respectively. These results indicate that, as the volume fraction of nanoparticles increases, the location of the start of the phase change process is postponed that this issue causes the increment of heat transfer from wall to fluid and the reduction of wall temperature. In general, it can be stated that, in boiling flows, using nanofluid because of the delay in boiling phenomenon has a good effect on heat transfer enhancement of heated walls. Also, the obtained results show that, by increasing Reynolds number, the created vapor phase reduces that leads to increase of the Nusselt number.

The paper investigates the effect of using nanofluid in phase change process of cooling fluid.