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This paper aims to coat ternary composite NiBP-graphite films by Dynamic Chemical Plating “DCP” technique with a growth rate of at least 5 μm/h, which makes this technique a worthy candidate for production of composite films. Electroless nickel plating method can be used to deposit nickel–phosphorous and nickel–boron coatings on metals or plastic surface. However, restrictions such as toxicity, short lifetime of the plating-bath and limited plating rate have limited applications of conventional electroless processes.

DCP is an alternative for producing metallic deposits on non-conductive materials and can be considered as a modified electroless coating process. Using a double-nozzle gun, two different solutions containing the precursors are sprayed simultaneously and separately onto the surface. With this technique, NiBP-graphite films are fabricated and their corrosion and tribological properties are investigated.

With a film thickness of 2 μm, tribological analysis confirms that these coatings have favorable anti-friction and anti-wear properties. Corrosion resistance of NiBP-graphite composite films was investigated, and it was found that graphite incorporation significantly enhances corrosion resistance of NiBP films.

DCP is faster and simpler to perform compared to other electroless deposition techniques. Using a double-nozzle gun, metal salt solution and reducing agents are sprayed to the surface, forming a deposit. Previously, coatings such as Cu, Cu-graphite, Cu-PTFE, Ni-B-TiO2, Ni-P, Ni-B-P and Ni-B-Zn with favorable compactness and adherence by DCP were reported. In this paper, the authors report the application of the DCP technique for depositing NiBP-PTFE nanocomposite films.

The purpose of this paper is to study the effects of using different Brownian models on natural and mixed convection fluid flow and heat transfer inside the square enclosure filled with the AlOOH–water nanofluid.

Due to fulfill of this demand, five different models for the effective thermal conductivity and viscosity of the nanofluid are considered. The following results are presented for the Ra=10⁷ to 10¹⁰ and Ri=0.01 to 100, whereas the volume fraction of the nanoparticles is varied from φ = 0.01 to 0.04.

According to the obtained results, increasing of Rayleigh number and reduction of Richardson number leads to the higher values of the average Nusselt number and entropy generation. Also, it is realized that, variation trend of the average Nusselt number and entropy generation in all cases is increasing by growing the volume fraction. It is found that the obtained average Nusselt numbers and entropy generations with Koo and Kleinstreuer are the highest among all the studied cases, and it is followed by Patel, Vajjha and Das, Corcione and Maxwell–Brinkman models, respectively.

Based on the results of present investigation, the Nusselt number difference predicted between the Maxwell–Brinkman model (as constant-property model) and Koo and Kleinstreuer model is about 7.84 per cent at 0.01 per cent volume fraction and 5.47 per cent at 0.04 per cent volume fraction for the Rayleigh number equal to 107. The entropy generation difference predicted between the two above studied model is about 8.05 per cent at 0.01 per cent volume fraction and 5.86 per cent at 0.04 per cent volume fraction for the Rayleigh number equal to 107. It is observed that using constant-property model has a significant difference in the obtained results with the results of other variable-property models.

This paper aims to reveal the challenges and problems of technology commercialization in an industrial development organization in Iran.

To achieve the objective of this paper, a mixed-methods case study was used. Initially, 15 in-depth interviews with technology commercialization experts were conducted and 43 themes were extracted as problems of technology commercialization. The outcomes of the interviews informed the development of the questionnaire. Subsequently, a survey of 205 experts was performed to examine the responses obtained from the interviews. The main problems were identified through exploratory factor analysis and evaluated through confirmatory factor analysis.

Seven factors are identified as the main difficulties of technology commercialization, including weakness in the commercialization process, challenges of the business environment, weak organizational structure, inefficient project management, ineffective cooperation with non-governmental sectors, failure to collaborate with stakeholders and conflicting political behaviors.

The outcomes of this research inform the organization’s managers of the poor conditions and barriers of the technology commercialization process. The findings also help managers to overcome the challenges that are under the control of the organization.

This paper contributes to the knowledge on technology commercialization by exploring the main factors that form barriers to and difficulties of technology commercialization in an industrial development organization and suggesting appropriate solutions.

By extending the service robot acceptance model (sRAM), this study aims to explore and enhance the acceptance of chatbots. The study considered functional, relational, social, user and gratification elements in determining the acceptance of chatbots.

By using the purposive sampling technique, data of 321 service customers, gathered from millennials through a questionnaire and subsequent PLS-SEM modeling, was applied for hypotheses testing.

Findings revealed that the functional elements, perceived usefulness and perceived ease of use affect acceptance of chatbots. However, in social elements, only perceived social interactivity affects the acceptance of chatbots. Moreover, both user and gratification elements (hedonic motivation and symbolic motivation) significantly influence the acceptance of chatbots. Lastly, trust is the only contributing factor for the acceptance of chatbots in the relational elements.

The study extends the literature related to chatbots and offers several guidelines to the service industry to effectively employ chatbots.

This is one of the first studies that used newly developed sRAM in determining chatbot acceptance. Moreover, the study extended the sRAM by adding user and gratification elements and privacy concerns as originally sRAM model was limited to functional, relational and social elements.

This study/paper aims to deal with thermal convection and entropy production of a ferrofluid in an enclosure having an isothermally warmed solid body placed inside. It should be noted that this research deals with a development of passive cooling system for the electronic devices.

The domain of interest is a square chamber of size L including a rectangular solid block of sizes l₁ and l₂. Thermal convection of ferrofluid (water–Fe₃O₄ nanosuspension) is analyzed within this enclosure. The solid body is considered to be isothermal with temperature T_h and also its area is L²/9. The vertical borders are cold with temperature T_c and the horizontal boundaries are adiabatic. The flow driven by temperature gradient in the cavity is two-dimensional. The governing equations, formulated in dimensionless primitive variables with corresponding initial and boundary conditions, are worked out by using the finite volume technique with the semi-implicit method for pressure-linked equations algorithm on a uniformly staggered mesh. The influence of nanoparticles volume fraction, aspect ratio of the solid block and an irreversibility ratio on energy transport and flow patterns are examined for the Rayleigh number Ra = 10⁷.

The results show that the nanoparticles concentration augments the thermal transmission and the entropy production increases also, while the augmentation of temperature difference results in a diminution of entropy production. Finally, lower aspect ratio has the significant impact on heat transfer, isotherms, streamlines and entropy.

An efficient numerical technique has been developed to solve this problem. The originality of this work is to analyze convective energy transport and entropy generation in a chamber with internal block. To the best of the authors’ knowledge, the effects of irreversibility ratio are scrutinized for the first time. The results would benefit scientists and engineers to become familiar with the analysis of convective heat transfer and entropy production in enclosures with internal isothermal blocks, and the way to predict the heat transfer rate in advanced technical systems, in industrial sectors including transportation, power generation, chemical sectors, electronics, etc.

This study aims to examine the effects of cross-flow and multiple jet impingement on conductive panel cooling performance when subjected to uniform magnetic field effects. The cooling system has double rotating cylinders.

Cross-flow ratios (CFR) ranging from 0.1 to 1, magnetic field strength (Ha) ranging from 0 to 50 and cylinder rotation speed (Rew) ranging from −5,000 to 5,000 are the relevant parameters that are included in the numerical analysis. Finite element method is used as solution technique. Radial basis networks are used for the prediction of average Nusselt number (Nu), average surface temperature of the panel and temperature uniformity effects when varying the impacts of cross-flow, magnetic field and rotations of the double cylinder in the cooling channel.

The effect of CFR on cooling efficiency and temperature uniformity is favorable. By raising the CFR to the highest value under the magnetic field, the average Nu can rise by up to 18.6%, while the temperature drop and temperature difference are obtained as 1.87°C and 3.72°C. Without cylinders, magnetic field improves the cooling performance, while average Nu increases to 4.5% and 8.8% at CR = 0.1 and CR = 1, respectively. When the magnetic field is the strongest with cylinders in channel at CFR = 1, temperature difference (ΔT) is obtained as 2.5 °C. The rotational impacts on thermal performance are more significant when the cross-flow effects are weak (CFR = 0.1) compared to when they are substantial (CFR = 1). Cases without a cylinder have the worst performance for both weak and severe cross-flow effects, whereas using two rotating cylinders increases cooling performance and temperature uniformity for the conductive panel. The average surface temperature lowers by 1.2°C at CFR = 0.1 and 0.5°C at CFR = 1 when the worst and best situations are compared.

The outcomes are relevant in the design and optimization-based studies for electric cooling, photo-voltaic cooling and battery thermal management.

The purpose of this paper is to underline the significance of invoking Big Data and Internet of Things (IoT) technologies in Omani Banks. Opportunities and challenges are also being discussed in the case study.

Four Omani banks representative of local, international, Islamic and specialized banks are being studied in terms of their social networking presence on Facebook and their e-banking facilities. Also, impetus is laid upon the aggregation of internal data and vast amounts of semi-structured external data from public sources, including social media.

The case study shows that Big Data analytics and IoT technologies may be utilized by the Omani banks for facilitating them in “forecasting” and “nowcasting”. Besides, customers may be better managed with better and efficient services. However, there are challenges in tapping these technologies such as security, infrastructure, regulatory norms, etc.

Banks in Oman need to appreciate the utility of Big Data and IoT technologies, and for this, a robust IT infrastructure should be institutionalized.

The case study is a major step in integrating Big Data and IoT technologies in Omani banks across four variants of national, international, Islamic and specialized banks. This is the first study where such integration has been emphasized in the Omani banking sector.

The analysis of fluid flow and thermal transport performance inside the cavity has found numerous applications in various engineering fields, such as nuclear reactors and solar collectors. Nowadays, researchers are concentrating on improving heat transfer by using ternary nanofluids. With this motivation, the present study analyzes the natural convective flow and heat transfer efficiency of ternary nanofluids in different types of porous square cavities.

The cavity inclination angle is fixed ω = 0 in case (I) and ω=π4 in case (II). The traditional fluid is water, and Fe3O4+MWCNT+Cu/H2O is treated as a working fluid. Ternary nanofluid's thermophysical properties are considered, according to the Tiwari–Das model. The marker-and-cell numerical scheme is adopted to solve the transformed dimensionless mathematical model with associated initial–boundary conditions.

The average heat transfer rate is computed for four combinations of ternary nanofluids: Fe3O4(25%)+MWCNT(25%)+Cu(50%),Fe3O4(50%)+MWCNT(25%)+Cu(25%),Fe3O4(33.3%)+MWCNT(33.3%)+Cu(33.3%) and Fe3O4(25%)+MWCNT(50%)+Cu(25%) under the influence of various physical factors such as volume fraction of nanoparticles, inclined magnetic field, cavity inclination angle, porous medium, internal heat generation/absorption and thermal radiation. The transport phenomena within the square cavity are graphically displayed via streamlines, isotherms, local and average Nusselt number profiles with adequate physical interpretations.

The purpose of this study is to determine whether the ternary nanofluids may be used to achieve the high thermal transmission in nuclear power systems, generators and electronic device applications.

The current analysis is useful to improve the thermal features of nuclear reactors, solar collectors, energy storage and hybrid fuel cells.

To the best of the authors’ knowledge, no research has been carried out related to the magneto-hydrodynamic natural convective Fe3O4+MWCNT+Cu/H2O ternary nanofluid flow and heat transmission filled in porous square cavities with an inclined cavity angle. The computational outcomes revealed that the average heat transfer depends not only on the nanoparticle’s volume concentration but also on the existence of heat source and sink.

Auxetics metamaterials show high performance in their specific characteristics, while the absolute stiffness and strength are much weaker due to substantial porosity. This paper aims to propose a novel auxetic honeycomb structure manufactured using selective laser melting and study the enhanced mechanical performance when subjected to in-plane compression loading.

A novel composite structure was designed and fabricated on the basis of an arrowhead auxetic honeycomb and filled with polyurethane foam. The deformation mechanism and mechanical responses of the structure with different structural parameters were investigated experimentally and numerically. With the verified simulation models, the effects of parameters on compression strength and energy absorption characteristics were further discussed through parametric analysis.

A good agreement was achieved between the experimental and simulation results, showing an evidently enhanced compression strength and energy absorption capacity. The interaction between the auxetic honeycomb and foam reveals to exploit a reinforcement effect on the compression performance. The parametric analysis indicates that the composite with smaller included angel and higher foam density exhibits higher plateau stress and better specific energy absorption, while increasing strut thickness is undesirable for high energy absorption efficiency.

The results of this study served to demonstrate an enhanced mechanical performance for the foam filled auxetic honeycomb, which is expected to be exploited with applications in aerospace, automobile, civil engineering and protective devices. The findings of this study can provide numerical and experimental references for the design of structural parameters.

Higher education and universities have faced unprecedented and ubiquitous changes. The University of Tehran or “UT,” as the leading university in Iran, is not immune to these changes. The purposes of this study is to investigate the current situation and future of the UT and gain insights and possible responses to changes that suit its strengths and potential to progress in an increasingly competitive, complex environment with uncertainties. It identifies deep fundamental underpinnings of the issue and highlights them for policymakers to formulate strategies and future vision of the UT.

Causal layered analysis (CLA) was applied as a framework and the data collected from different sources such as literature reviews, content analysis of rules, regulations and master plans of the university and coded interviews of four different groups of university stakeholders were analyzed. The current system of UT, as well as hidden beliefs, that maintains traditional perceptions about university was mapped. Next, by applying a new recursive process and reverse CLA order, new CLA layers extracted through an expert panel, the layers of CLA based on new metaphors to envision future of UT were backcasted.

The results from CLA layers including litany, system, worldview and metaphor about the current statue of UT show disinterest and inertia against changes, conservative, behind the times and traditional perceptions, and indicate that the UT system is mismatched to the needs of society and stakeholders in the future. The authors articulated alternative perspectives deconstructed from other worldviews so there are new narratives that reframe the issues at hand. The results show that to survive in this fast-paced revolution and competition in higher education, UT should develop scenarios and formulate new strategies.

The authors had limited access to a wide range of stakeholders. As the UT is a very big university with so many faculties and departments, to access a pool of experts and top policymakers who were so busy and did not have time to interview inside and outside of university was very hard for the research team. The authors also had limitation to access the internal enactments and decisions of the trustee board of the UT and the financial balance sheets of the university.

In this paper, by mixing different methods of futures studies, the authors have shown how to move forward while understanding the perspectives of stakeholders about the future of UT by a new recursive process and reverse CLA order. A supplementary phase was added to improve CLA and to validate the method and results, which were ignored in previous studies.