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The purpose of this study is to analyze the impacts of combined utilization of multi-jet impinging cooling of nanofluids with magnetic field and porous layer on the cooling performance, as effective cooling with impinging jets are obtained for various energy systems, including photovoltaic panels, electronic cooling and many other convective heat transfer applications.

Finite element method is used to explore the magnetic field effects with the inclusion of porous layer on the cooling performance efficiency of slot nanojet impingement system. Impacts of pertinent parameters such as Reynolds number (Re between 250 and 1,000), strength of magnetic field (Ha between 0 and 30), permeability of the porous layer (Da between 0.001 and 0.1) on the cooling performance for flat and wavy surface configurations are explored.

It is observed that the average Nusselt number (Nu) rises by about 17% and 20.4% for flat and wavy configuration while temperature drop of 4 K is obtained when Re is increased to 1,000 from 250. By using magnetic field at the highest strength, the average Nu rises by about 29% and 7% for flat and wavy cases. Porous layer permeability is an effective way of controlling the cooling performance while up to 44.5% variations in the average Nu is obtained by varying its value. An optimization routine is used to achieve the highest cooling rate while the optimum parameter set is obtained as (Re, Ha, Da, γ, sx) = (1,000, 30, 0.07558, 86.28, 2.585) for flat surface and (Re, Ha, Da, γ, sx) = (1,000, 30, 0.07558, 71.85, 2.329) for wavy surface configurations.

In thermal systems, cooling system design is important for thermal management of various energy systems, including fuel cells, photovoltaic panels, electronic cooling and many others. Impinging jets are considered as effective way of cooling because of its ability to give higher local heat transfer coefficients. This paper offers novel control tools, such as magnetic field, installation of porous layer and hybrid nano-liquid utilization for control of cooling performance with multiple impinging jets.

The purpose of this study was to investigate the determinants of purchase intentions for utilitarian and hedonic counterfeit sporting goods among Muslim’ consumers. The moderating effect of income and status consumption was also examined.

Questionnaires were distributed among male undergraduate university students who were consumers of sports goods. A total of 360 valid and usable questionnaires were collected and analyzed through descriptive and inferential statistics.

The results showed that perceived risk, personal gratification, religiosity, information susceptibility and normative susceptibility all have a positive and significant effect on negative attitudes toward counterfeit sports goods. The effect of a negative attitude toward counterfeit goods was also negative and significant for the intention to purchase utilitarian and hedonistic goods. Income was not a moderator in the relationship between negative attitudes and the intention to purchase utilitarian and hedonic goods. However, the moderating effect of status consumption on the intention to purchase both utilitarian and hedonic goods was significant.

The use of a male-only student sample potentially limits the generalization of the findings, but not the underlying relationships between the variables. Efforts to discourage or prevent the purchase of counterfeit sporting goods should highlight the risk and reduced personal gratification associated with purchasing counterfeit products, while also appealing to a person’s faith-based ethics.

This study produces a novel model explaining the purchase intentions for utilitarian and hedonic counterfeit sporting goods. This model can inform the development of anti-counterfeiting strategies in Muslim countries.

The library is one of the critical foundations of informing and educating the public, and it should fulfil its function in the community, which is disseminating knowledge effectively. The library must have a dynamic space and an appropriate atmosphere to do this. Also, librarians should assist clients outside of stressful work environments. This study aimed to examine the association between organizational climate and job burnout in the hospital and college libraries of Shahid Beheshti University of Medical Sciences.

This study is a cross-sectional survey. The population includes all librarians working in the college and hospital libraries of Shahid Beheshti University of Medical Sciences. Two questionnaires, including organizational climate “ClimateQUAL” and job burnout “Maslach and Jackson”, were applied to collect data. It was hypothesized that there is a correlation between the organizational climate and the burnout of librarians.

The findings revealed that the organizational climate and job burnout are not in a favourable situation, with average scores of 4.70 and 2.50, respectively. Furthermore, there is a significant statistical relationship between organizational climate and job burnout (p-value<0.001).

Knowledge of the significant relationship between the organizational climate and job burnout in medical libraries may encourage policymakers to make more efforts to provide their staff with a better climate and less burnout. Regarding that it is crucial to enhance the existing condition in medical libraries, the findings of the present study suggest that policymakers should be conscious of improving the current condition, which could lead to promoting patrons’ satisfaction and productivity in the mentioned libraries.

This paper aims to investigate the effect of centrifugal disk finishing (CDF) technique on the surface and subsurface characteristics of the fused deposited modeling (FDM) parts in both theoretical and experimental aspects. From theoretical aspect, a novel theoretical model is developed as a function of layer deposition orientation, layer thickness, finishing working time, density ratio and hardness ratio to estimate the surface roughness profile of FDM part at different finishing conditions and finishing time intervals. Meanwhile, from the experimental aspect, an experimental campaign was performed under different mechanical and mechanical-chemical finishing conditions to verify the theoretical model and also assess the surface and subsurface characteristics of the polished parts.

The theoretical model commences with an approximation of surface profile of the FDM part through a sequence of parabola arcs, continues with the calculation of reference line and machined surface profile and leads to a formulation of surface roughness of as-printed and polished surface. In the experimental section, the FDM parts are polished under dry, pure water, 25% and 50% volumetric aqueous acetone solutions finishing conditions through CDF technique.

The comparison between experimental and theoretical results reveals 9% mean absolute error between theoretical and experimental results. Meanwhile, Rq reduction percentage of polished parts under dry, pure water, 25% and 50% aqueous acetone solutions are 66.1%, 54.5%, 56.9% and 67.2%, respectively. The scanning electron microscopy results reveal severe layer damage in dry finishing condition, while the application of 50% aqueous acetone as a polishing solution completely eliminates layer damage. Another promising finding was sticky material phenomenon on the surface of polished part under 25% finishing condition. The Shore hardness test illustrates that the surface hardness improvement of the polished parts under dry, pure water, 25% and 50% aqueous acetone solutions finishing conditions are 8.4%, 2.25%, 4.36% and 10.8%, respectively. The results also revealed that the dimension variation of polished parts under dry, pure water, 25% and 50% aqueous acetone solutions are 0.634%, 0.525%, 0.545% and 0.608%, respectively. The edge profile radius of the as-printed part is 134 µm, while the edge profiles radius of the polished parts under dry, pure water, 25% aqueous acetone solution and 50% aqueous acetone solution are 785.5 µm, 545.5 µm, 623.5 µm and 721.5 µm, respectively, at the polishing time of 720 min.

This paper fulfills an identified need to study the benefits of the mechanical-chemical polishing technique in comparison to mechanical and chemical polishing strategy of the FDM parts for the first time. Beside the experimental campaign, the novel analytical formulation of surface roughness as a function of mechanical properties of abrasive media and FDM part and finishing specifications provides a valuable insight in the case of material-removal processes.

This study aims to simulate Hunter turbine in Computer Forensic Examiner (CFX) environment dynamically. For this purpose, the turbine is designed in desired dimensions and simulated in ANSYS software under a specific fluid flow rate. The obtained values were then compared with previous studies for different values of angles (θ and α). The amount of validation error were obtained.

In this research, at first, the study of fluid flow and then the examination of that in the tidal turbine and identifying the turbines used for tidal energy extraction are performed. For this purpose, the equations governing flow and turbine are thoroughly investigated, and the computational fluid dynamic simulation is done after numerical modeling of Hunter turbine in a CFX environment.

The failure results showed; 11.25% for the blades to fully open, 2.5% for blades to start, and 2.2% for blades to close completely. Also, results obtained from three flow coefficients, 0.36, 0.44 and 0.46, are validated by experimental data that were in high-grade agreement, and the failure value coefficients of (0.44 and 0.46) equal (0.013 and 0.014), respectively.

In this research, at first, the geometry of the Hunter turbine is discussed. Then, the model of the turbine is designed with SolidWorks software. An essential feature of SolidWorks software, which was sorely needed in this project, is the possibility of mechanical clamping of the blades. The validation is performed by comparing the results with previous studies to show the simulation accuracy. This research’s overall objective is the dynamical simulation of Hunter turbine with the CFX. The turbine was then designed to desired dimensions and simulated in the ANSYS software at a specified fluid flow rate and verified, which had not been done so far.

Double-diffusive convection within a tri-dimensional in a horizontal annulus partially filled with a fluid-saturated porous medium is numerically investigated. The aim of this work is to understand the effects of a source of heat and solute on the fluid flow and heat and mass transfer rates.

In the formulation of the problem, the Darcy–Brinkman–Forchheimer model is adopted to the fluid flow in the porous annulus. The laminar flow regime is considered under steady state conditions. Moreover, the transport equation for continuity, momentum, energy and mass transfer are solved using the Patankar–Spalding technique.

Through this investigation, the predicted results for both average Nusselt and Sherwood numbers were correlated in terms of Lewis number, thermal Grashof number and buoyancy ration. A comparison was made with the published results and a good agreement was found.

The paper’s results are validated by favorable comparisons with previously published results. The results of the problem are presented in graphical forms and discussed. This paper aims to study the behavior of the flow structure and heat transfer and mass for different parameters.

This study aimed to analyze the lipid content and fatty acid composition in the liver and muscle of a porcupinefish species inhabiting waters around the Ryukyu Islands to investigate their potential as a source of long-chain n-3 polyunsaturated fatty acids (LC-PUFAs).

Porcupinefish were collected along the Okinawa Island coast. The composition of fatty acids and cholesterol in both liver and muscle were analyzed using a gas chromatograph mass spectrometer.

The liver of Okinawan long-spine porcupinefish was rich in lipids whose content correlated to the proportion of liver/body weight. Fatty acid compositions in their liver and muscles were similar to each other. LC-PUFAs occupied 44% of total fatty acids, with docosahexaenoic acid (DHA) being the dominant (42%), whereas eicosapentaenoic acid occupied 2.4%. The liver contained 1,690 mg of cholesterol and 14.8 g of DHA per 100 g, whose proportion decreased in summer compared to other seasons (p = 0.036).

The liver of Okinawan long-spine porcupinefish, which has not yet been commercially used although its non-toxicity is claimed, can be an excellent source of LC-PUFAs, especially DHA, accentuating its potential in food supplements’ production.

The purpose of this paper is to evaluate the temperature, the Dirichlet conditions have been considered to the parallel horizontal plates. The model of generalized Brinkman-extended Darcy with the Boussinesq approximation is considered and the governing equations are computed by COMSOL multiphysics.

In the current study, the thermodynamic irreversible principle is applied to study the unsteady Poiseuille–Rayleigh–Bénard (PRB) mixed convection in a channel (aspect ratio A = 5), with the effect of a uniform transverse magnetic field.

The effects of various flow parameters on the fluid flow, Hartmann number (Ha), Darcy number (Da), Brinkman number (Br) and porosity (ε), are presented graphically and discussed. Numerical results for temperature and velocity profiles, entropy generation variations and contour maps of streamlines, are presented as functions of the governing parameter mentioned above. Basing on the generalized Brinkman-extended Darcy formulation, which allows the satisfaction of the no-slip boundary condition on a solid wall, it is found that the flow field and then entropy generation is notably influenced by the considering control parameters. The results demonstrate that the flow tends toward the steady-state with four various regimes, which strongly depends on the Hartman and Darcy numbers variations. Local thermodynamic irreversibilities are more confined near the active top and bottom horizontal walls of the channel when increasing the Da and decreasing the Hartmann number. Entropy generation is also found to be considerably affected by Brinkman number variation.

In the present work, we are presenting our investigations on the influence of a transverse applied external magnetohydrodynamic on entropy generation at the unsteady laminar PRB flow of an incompressible, Newtonian, viscous electrically conducting binary gas mixture fluid in porous channel of two horizontal heated plates. The numerical solutions for the liquid velocity, the temperature distribution and the rates of heat transport and entropy generation are obtained and are plotted graphically.

This paper evaluates the benefits of harnessing artificial intelligence (AI) tools for safety compliance on construction projects in Nigeria.

This study employed a specialised approach by combining qualitative and quantitative approach. The study carried out a brief systematic literature review (SLR) to identify the variables of the study. These variables were prepared in a questionnaire which was distributed among professionals within the Nigerian construction sector using purposive sampling. A total of 140 questionnaires were retrieved. The collected data were analysed using Relative Importance Index (RII), Ginni’s Mean (GM) and exploratory factor analysis (EFA).

The analysis revealed that all the identified benefits hold considerable importance, with an average RII of 0.86, with real-time monitoring as the most prominent advantage. However, using the GM which was 0.861, the study identified “mitigation of hazards on worksites” as the stationary benefit of AI in safety compliance.

The study was conducted exclusively within Nigeria’s Federal Capital Territory, using a cross-sectional survey approach.

The results will be valuable for professionals and practitioners in the Nigerian construction sector, as they will acquire insights into the potential advantages of utilising AI tools for monitoring of safety compliance on construction projects.

The study adopted a robust approach by identifying the stationary benefit using the GM in combination with RII and EFA.