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1 – 10 of 50Latifah Falah Alharbi, Umair Khan, Aurang Zaib, S.H.A.M. Shah, Anuar Ishak and Taseer Muhammad
Thermophoresis deposition of particles is a crucial stage in the spread of microparticles over temperature gradients and is significant for aerosol and electrical technologies. To…
Abstract
Purpose
Thermophoresis deposition of particles is a crucial stage in the spread of microparticles over temperature gradients and is significant for aerosol and electrical technologies. To track changes in mass deposition, the effect of particle thermophoresis is therefore seen in a mixed convective flow of Williamson hybrid nanofluids upon a stretching/shrinking sheet.
Design/methodology/approach
The PDEs are transformed into ordinary differential equations (ODEs) using the similarity technique and then the bvp4c solver is employed for the altered transformed equations. The main factors influencing the heat, mass and flow profiles are displayed graphically.
Findings
The findings imply that the larger effects of the thermophoretic parameter cause the mass transfer rate to drop for both solutions. In addition, the suggested hybrid nanoparticles significantly increase the heat transfer rate in both outcomes. Hybrid nanoparticles work well for producing the most energy possible. They are essential in causing the flow to accelerate at a high pace.
Practical implications
The consistent results of this analysis have the potential to boost the competence of thermal energy systems.
Originality/value
It has not yet been attempted to incorporate hybrid nanofluids and thermophoretic particle deposition impact across a vertical stretching/shrinking sheet subject to double-diffusive mixed convection flow in a Williamson model. The numerical method has been validated by comparing the generated numerical results with the published work.
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Mohamed M. Hendy and Magdy A. Ezzat
Whereas, the classical Green-Naghdi Type II (GN-II) model struggles to accurately represent the thermo-mechanical behavior of thermoelectric MHD due to its inability to account…
Abstract
Purpose
Whereas, the classical Green-Naghdi Type II (GN-II) model struggles to accurately represent the thermo-mechanical behavior of thermoelectric MHD due to its inability to account for the memory effect. A new mathematical model of the GN-II theory incorporates a fractional order of heat transport to address this issue.
Design/methodology/approach
The employment of the matrix exponential method, which forms the basis of the state-space approach in contemporary theory, is central to this strategy. The resulting formulation, together with the Laplace transform techniques, is applied to a variety of problems. Solutions to a thermal shock problem and to a problem of a layer media both without heat sources are obtained. Also, a problem with the distribution of heat sources is considered. The numerical technique is used to achieve the Laplace transform inversion.
Findings
According to the numerical results and its graphs, the influences of the fractional order parameters, figure-of-merit factor, thermoelectric power and Peltier coefficient on the behavior of the field quantities are investigated in the new theory.
Originality/value
The new modeling of thermoelectric MHD has advanced significantly as a result of this work, providing a more thorough and precise tool for forecasting the behavior of these materials under a range of thermal and magnetic conditions.
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Latifah Falah Alharbi, Umair Khan, Aurang Zaib and Anuar Ishak
A novel type of heat transfer fluid known as hybrid nanofluids is used to improve the efficiency of heat exchangers. It is observed from literature evidence that hybrid nanofluids…
Abstract
Purpose
A novel type of heat transfer fluid known as hybrid nanofluids is used to improve the efficiency of heat exchangers. It is observed from literature evidence that hybrid nanofluids outperform single nanofluids in terms of thermal performance. This study aims to address the stagnation point flow induced by Williamson hybrid nanofluids across a vertical plate. This fluid is drenched under the influence of mixed convection in a Darcy–Forchheimer porous medium with heat source/sink and entropy generation.
Design/methodology/approach
By applying the proper similarity transformation, the partial differential equations that represent the leading model of the flow problem are reduced to ordinary differential equations. For the boundary value problem of the fourth-order code (bvp4c), a built-in MATLAB finite difference code is used to tackle the flow problem and carry out the dual numerical solutions.
Findings
The shear stress decreases, but the rate of heat transfer increases because of their greater influence on the permeability parameter and Weissenberg number for both solutions. The ability of hybrid nanofluids to strengthen heat transfer with the incorporation of a porous medium is demonstrated in this study.
Practical implications
The findings may be highly beneficial in raising the energy efficiency of thermal systems.
Originality/value
The originality of the research lies in the investigation of the Darcy–Forchheimer stagnation point flow of a Williamson hybrid nanofluid across a vertical plate, considering buoyancy forces, which introduces another layer of complexity to the flow problem. This aspect has not been extensively studied before. The results are verified and offer a very favorable balance with the acknowledged papers.
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Shahd A.A. Alsayari, Rehab F.M. Ali, Sami A. Althwab and Mona S. Almujaydil
This study aims to assess the oxidative stability of avocado oil (AO) at various temperatures, using butylated hydroxytoluene (BHT) as an artificial antioxidant and different…
Abstract
Purpose
This study aims to assess the oxidative stability of avocado oil (AO) at various temperatures, using butylated hydroxytoluene (BHT) as an artificial antioxidant and different concentrations of ultrasonic extract of Chlorella vulgaris.
Design/methodology/approach
Extracts of C. vulgaris were obtained using four solvents: water, acetone, ethanol and 80% ethanol-aqueous. Standard techniques were used to conduct qualitative phytochemical screening of the extracts. The extracted samples were analyzed for total phenolics, total flavonoids, antioxidant activity and phenolic compound fractionation. Some physicochemical parameters of AO treated with various concentrations of C. vulgaris ultrasonic extract compared to a 200 ppm BHT and exposed to different temperatures were measured.
Findings
The highest phenolic, flavonoids content and antioxidant activity was achieved by 80% ethanolic extract of C. vulgaris . The results showed that exposure of AO to high temperatures led to significant changes in the oil's physicochemical properties. These changes increased as the temperature increased. On the other hand, adding 80% ethanolic extract of C. vulgaris into AO reduced the effect of heat treatment on the change in physicochemical properties.
Originality/value
Adding 80% ethanolic extract of C. vulgaris into AO can potentially reduce the impact of heat treatment on the alteration of physicochemical properties.
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The purpose of this study is to explore the role of gold as a hedge against inflation in the case of the United Arab Emirates.
Abstract
Purpose
The purpose of this study is to explore the role of gold as a hedge against inflation in the case of the United Arab Emirates.
Design/methodology/approach
The study utilizes monthly data on the local sharia-compliant spot gold contract traded on the Dubai Gold and Commodity Exchange (DGCX) and the corresponding consumer price index series over the period December 2015 to January 2021. The econometric approach employed by the study involves a unit root testing procedure that allows the timing of significant breaks to be estimated. A cointegration analysis is then conducted using a nonlinear autoregressive distributed lag (NARDL) model, taking into consideration the presence of structural breaks in addition to short- and long-run asymmetries.
Findings
The results reveal that consumer and gold prices are cointegrated, which implies that investing in gold can hedge against inflation in the long run. No sufficient evidence, nonetheless, is found in support of the ability of gold to serve as a hedge against inflation in the short run.
Originality/value
The findings have several important policy implications for policymakers and investors that are further discussed in the study.
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Asiyah S.D.A. Alshammai, Rehab F.M. Ali and Raghad M. Alhomaid
This study aims to find out how pomposia fruit powder (Syzygium cumini L.) mixed with roasted coffee (RCO) affected antioxidants, phytochemicals, lipid peroxidation inhibition and…
Abstract
Purpose
This study aims to find out how pomposia fruit powder (Syzygium cumini L.) mixed with roasted coffee (RCO) affected antioxidants, phytochemicals, lipid peroxidation inhibition and sensory attributes.
Design/methodology/approach
Pomposia fruits (Syzygium cumini L.) powder (PFP) was integrated with RCO at levels of 0.0%, 5.0%, 10.0%, 15.0% and 20.0%. RCO, PFP and binary mixtures containing RCO: PFP were evaluated for their total phenolics (TP), total flavonoids (TF), anthocyanin content (AC), antioxidant activity and phenolic compounds fractionation. The oxidative indices of coffee oil samples were measured throughout different storage intervals. Additionally, sensory characteristics of RCO enriched with different PFP doses were evaluated.
Findings
PFP samples exhibited the greatest TP content (1910 mg/100 g), whereas RCO samples had the lowest concentration (1090 mg/100 g). As more PFP was added, the corresponding coffee blends’ concentrations of TP, TF and AC were improved significantly. PFP possesses a radical-scavenging activity that is about 1.20 times more than RCO’s. DPPH (2,2-diphenyl-1-picrylhydrazyl) radical-scavenging activity jumped significantly from 74.13% in control (untreated) samples to 77.64%, 78.39% and 80.15% for samples enriched with 10.0%, 15.0% and 20% PFP, respectively. Significant increases in gallic acid, hesperidine, benzoic acid, chlorogenic acid, hispertin, catechol, quercetin, pyrogallol and rutin were detected when RCO was mixed with different quantities of PFP. At the end of storage trial, the coffee oil treated with 20% PFP had AV, PV and TBA values that were about 1.70, 1.95 and 1.66 times lower, respectively, than those of the control sample that had not had PFP addition. The RCO with 5.0% PFP achieved the greatest over acceptability grades.
Originality/value
To the best of the authors’ knowledge, this study was the first study to evaluate the effect of incorporating various level of pomposia fruit powder into RCO. The findings shows that adding different concentrations of pomposia fruit powder into RCO can indeed enhance the radical-scavenging activity of the coffee and potentially extend its shelf life.
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Ayman El-Anany, Rehab F.M. Ali, Mona S. Almujaydil, Reham M. ALgheshairy, Raghad Alhomaid and Hend F. Alharbi
This study aims to evaluate the nutrient content and acceptable qualities of plant-based burger patties (PBBP) formulated with chickpea flour, defatted sesame cake (DSC) flour…
Abstract
Purpose
This study aims to evaluate the nutrient content and acceptable qualities of plant-based burger patties (PBBP) formulated with chickpea flour, defatted sesame cake (DSC) flour, coffee silver skin and pomegranate juice as colorant.
Design/methodology/approach
The chemical composition, energy value, cholesterol content, amino acid composition, cooking loss, pH, color characteristics and sensory attributes of PBBP were analyzed using official procedures and compared to beef burger.
Findings
PBBP had a protein value of 16.0 g/100g, which is nearly close to the protein content of the beef burger (18.1 g/100g). The fat content of the PBBP was approximately three times lower than that of the beef burger. The fiber content in PBBP was approximately 23 times as high as that in beef burgers samples (p = 0.05). The raw PBBP samples supplies 178 Kcal/100g, whereas beef burger possessed 259 Kcal/100g. Neither the raw nor the cooked PBBP samples contained any cholesterol. Both the beef and PBBP displayed acceptability scores higher than 7.0, which suggests that PBBP was well accepted.
Originality/value
It is concluded that the PBBP sample exhibited a protein value of 16.0 g/100g, which is comparable to the protein level of beef burgers (18.1 g/100g). The fat level of the PBBP samples was significantly lower than that of the beef burger samples. Uncooked PBBP samples contained significantly higher fiber content compared to beef burger samples. No cholesterol was found in raw or cooked PBBP samples. Overall acceptance scores for both beef and PBBP samples exceeded 7.0, suggesting that the proposed product (PBBP) was received favorably.
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Affordable housing provision is one of the visions of the Kingdom of Saudi Arabia (KSA), as highlighted in Vision 2030. For about 21 months now, the coronavirus disease 2019…
Abstract
Purpose
Affordable housing provision is one of the visions of the Kingdom of Saudi Arabia (KSA), as highlighted in Vision 2030. For about 21 months now, the coronavirus disease 2019 (COVID-19) pandemic has ravaged the world and has increased the level of economic crisis and financial uncertainty to achieve planned projects. Studies investigating the reality of how the COVID-19 pandemic may streamline the chances of achieving affordable housing for all in 2030 are scarce. Thus, this study examined the relevance of affordable housing, the perceived impact of COVID-19 on affordable housing and proffered measures to promote affordable housing finance in Vision 2030.
Design/methodology/approach
Medina, Riyadh and Al Qassim were the participants' cities engaged via panel interviews and supported by existing relevant Vision 2030 documents. The Delphi method was adopted to explore the government officials, financial operators (bankers), academicians and employees' opinions, and the analysed data presented in themes.
Findings
Findings show that SA Vision 2030 blueprint expresses an exemplary country in all ramifications, including affordable housing finance for the citizens. Findings reveal that the COVID-19 pandemic threatens SA affordable housing finance Vision 2030. The increased housing shortage, high construction housing cost, increased foreclosures, increased eviction, possible homelessness, financial instability and vulnerability emerged as the perceived impact of COVID-19 on affordable housing finance in Vision 2030. Refinancing housing loans to boost Vision 2030, forbearance to promote Vision 2030, improve payment relief, among others, emerged as measures to promote affordable housing in the post-COVID-19 era.
Research limitations/implications
The research only identified the possible negative impacts of the COVID-19 pandemic on affordable housing finance in Vision 2030 and proffered policy solutions from the engaged participants' perspective. Also, the study covered three cities (Medina, Riyadh and Al Qassim). The suggestions that will emerge from this research may be adopted to address other sectors captured in Vision 2030 that are critical and hit by the ravaging pandemic.
Practical implications
Measures such as refinancing mortgages and strengthening government housing agencies will promote affordable housing for Vision 2030 if the relevant policymakers and mortgage institutions are well implemented.
Originality/value
This research identified the perceived early threats from the COVID-19 pandemic that could affect affordable housing transformation in Vision 2030 from the participants' perspective. Studies regarding COVID-19 and affordable housing in Vision 2030 are very few.
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Makhmoor Bashir and M. Muzamil Naqshbandi
The research on sustainable business model innovation (SBMI) has seen a surge over the years. However, despite the surge, the literature on the antecedents of SBMI is still at a…
Abstract
Purpose
The research on sustainable business model innovation (SBMI) has seen a surge over the years. However, despite the surge, the literature on the antecedents of SBMI is still at a budding stage. Therefore, the purpose of this paper is to expand the literature on SBMI by investigating the influence of managerial ties on SBMI.
Design/methodology/approach
Data were collected from 200 SMEs in Saudi Arabia to test the conceptual model, which was analysed using structural equation modelling.
Findings
The findings highlighted the significance of managerial ties in promoting SBMI. Furthermore, the findings highlighted that managerial ties might not optimally result in SBMI uncles channelized through absorptive capacity. However, the findings could not confirm the moderating role of strategic flexibility.
Practical implications
The findings from this study have implications for SME owners, recommending that these firms develop managerial ties and absorptive capacities to realize the benefits of SBMI.
Originality/value
To the best of the authors’ knowledge, this study is one of the first to highlight the significance of managerial ties in promoting SBMI from an emerging market perspective.
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Hossam Wefki, Mona Salah, Emad Elbeltagi, Asser Elsheikh and Rana Khallaf
Given the growing interest in modern construction techniques and the emergence of innovative technologies, construction site layout planning research has progressively been…
Abstract
Purpose
Given the growing interest in modern construction techniques and the emergence of innovative technologies, construction site layout planning research has progressively been investigating approaches to adopt innovative concepts and incorporate renewed approaches to improve widespread efficiency. This research develops a decision-making tool that optimizes construction site layout plans. The developed model targets two main objectives: minimizing material transportation costs and maximizing safety by optimally placing facilities on construction sites.
Design/methodology/approach
A novel approach is devised based on the integration of Building Information Modeling and Generative Design (BIM-GD). This engine is used to optimize the multi-objective site layout problems to identify layout alternatives in the early project stages. Parametric modeling uses Dynamo to construct the model and explore constraints initially. Finally, the GD environment is utilized to create different design alternatives, and then the decision-making procedure selects the most appropriate design alternative. Additionally, a case study is applied to validate the effectiveness of the developed model.
Findings
The results indicate the effectiveness of the proposed GD tool and its potential for more complex applications. The GD engine examined optimal layout plans, balancing different objectives and adhering to appointed geometric constraints. A case study was conducted to assess the model's effectiveness and showcase its suitability. Construction Site Layout Planning (CSLP) is an essential step in design that can influence considerable aspects, such as material transportation expenses and different safety standards on the site. Employing visual programming for parametric modeling within Dynamo-Revit creates an expedient and user-friendly platform for planning engineers who may require more programming expertise to create and program algorithmic models visually. Utilizing GD in CSLP has proven to be a powerful tool with consequential prospects for improving applications and executing more models.
Practical implications
The findings from this framework are intended to help construction practitioners select the most appropriate site layout during early project stages while incorporating different safety criteria inside construction sites to alleviate actual safety risks.
Originality/value
A new approach is proposed that utilizes an integrated BIM-GD engine to optimize multi-objective site layout problems. This approach targets two main objectives: minimizing material transportation costs and maximizing safety by optimally placing facilities in construction sites.
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