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This study evaluates low Reynolds number models of turbulence for numerical computations on the heat transfer and fluid flow behavior in a rectangular channel with streamwise‐periodic ribs mounted on one of the principal walls. The models include k − ε models of Launder and Sharma (1974), Chien (1982), k − ε model of Lin and Hwang (1998), Wilcox’s k−ω model (Wilcox, 1994) and Durbin’s model k − ε −v² (Durbin, 1995). The numerical results show that all these models can predict the flowfield reasonably well, and the inclusion of the Yap term (Yap, 1987) in the ε – equation (or ε – equation) can further improve the prediction in these k − ε models, k − ε model and k − ε − v² model. However, these models behave differently in heat transfer computations. The k − ω model leads to too low a level of heat transfer and turbulence. Among these k − ε models and the k − ε model, Lin’s model with the Yap term predicts the heat transfer level best. Durbin’s model with extra v², f equations and the Yap term exhibits further improvement.

A numerical investigation to determine the velocity and heat transfer characteristics of multiple impinging slot jets in rib‐roughened channels in the presence of cross‐flow has been carried out. Fluid flow is modeled using an explicit algebraic stress model. A simple eddy diffusivity and a generalized gradient diffusion hypothesis are applied for the modeling of turbulent heat fluxes. The computations are validated against available experimental fluid flow and heat transfer data. Different size and arrangement of jets and ribs are considered in detail, while the Reynolds numbers of a jet and the channel inlet are fixed at 6,000 and 14,000, respectively. Results show that the ratio (B/W) between the size of the jets and ribs is most important. An explanation is that the ribs inhibit the motion of eddies by preventing them from coming very close to the surface when B/W is low, e.g. B/W = 1, although the ribs will increase the turbulence intensity. This blockage limited the heat transfer enhancement effect of the ribs and impinging jets.

Performance of various k‐ε models on turbulent forced convection in a channel with periodic ribs is assessed.

The influence of the Yap correction and the non‐linear stress‐strain relation on the predictions of mean‐flow, turbulence quantities and local heat transfer rate is examined. The effect of thermal boundary conditions on the heat transfer predictions is investigated by employing both the prescribed heat flux approach and the conjugate heat transfer approach.

It was found that the inclusion of the Yap correction in the ε‐equation significantly improves the predictions of mean velocity and wall heat transfer for both high‐Reynolds number and low‐Reynolds number k‐ε models in the present ribbed channel flow with massive flow separation. The employment of the non‐linear stress‐strain relation only marginally improves the predictions of turbulence quantities: the turbulence anisotropy is reproduced although the level of turbulence intensity is still too low. In general, the conjugate heat transfer approach predicts better average Nusselt number than the prescribed heat flux approach. However, both approaches under‐predict the experimental value by about 28‐33 percent when the low‐Reynolds number k‐ε model of Lien and Leschziner (1999) with the Yap term is adopted.

Thorough numerical treatments of the thermal boundary conditions at the solid‐liquid interface, and detailed periodic condition in the periodic regime, were given in the paper to benefit researchers interested in solving similar problems.

The purpose of this computational fluid dynamics (CFD)-based study on semicircular rib-roughened equilateral triangular duct is to investigate heat transfer, friction factor and thermohydraulic performance parameter. The analysis is carried out by simulating problem in ANSYS (Fluent). The Reynolds number in the study varies from 4,000 to 24,000. Nusselt number is calculated for different Reynolds number using various turbulent models available in ANSYS (Fluent) for a smooth duct and compared the results with the Dittus–Boelter correlation.

The analysis has been done by solving basic fluid governing equations (continuity, momentum and energy) by using finite volume method (FVM). The semicircular ribs were fabricated on the absorber plate. The constant amount of heat flux is applied on the absorber plate, whereas other two walls are made adiabatic. The semi-implicit method for pressure linked equations (SIMPLE) algorithm is used with pressure–velocity-coupled disretization to estimate the results. The selection of turbulent model has been done on the basis of Nusselt number prediction in the smooth duct.

The renormalization-group k − ε model predicts the Nusselt number more accurately as compared to standard k − ε model, standard k − ω model, shear stress transport (SST) k − ω and realizable k − ε model in the Reynolds number ranges from 4,000 to 24,000 with a ± 5.5% deviation from Dittus–Boelter equation for smooth duct. The maximum thermo-hydraulic performance is observed of the order of 1.7 for arrangement which has a relative roughness height of 0.067 and relative roughness pitch of 7.5 at higher Reynolds Number of 24,000.

Although, many experimental studies are available in the area of rib-roughened ducts, the present study is based on CFD analysis of semicircular rib-roughened equilateral triangular duct and the results are predicted in terms of Nusselt number, friction factor and thermohydraulic performance parameter. Moreover, the predicted result of Nusselt number and friction factor is validated by comparing with Dittus–Boelter correlation and modified Blasius equation, respectively. This advantage made Fluent a powerful tool for analyzing the internal fluid flow through roughened ducts.

Amid rising environmental concerns, Industry 4.0 and blockchain technology (BCT) are transforming circular economy practices and prevailing business models. Recognizing the same, the current study examines the role of advanced technology in circular practices and their impact on eco-environmental performance, which influences organizational performance. The study collects data from 185 food processing enterprises that are located in Malaysian territories. By employing CB-SEM modeling, the study provides three key findings. First, Industry 4.0 significantly improves the circular economy practices. Second, circular economy practices help to improve firms' environmental performance but did not stimulate operational performance. Third, higher eco-environmental performance significantly boosts organizational performance. This study set out the foundations for participating countries/firms that help to achieve sustainable goals through the integration of blockchain technology in circular economy practices.

This study proposes a collaborative federated learning (CFL) framework to address personal data transmission and retention issues for artificial intelligence (AI)-enabled video surveillance in public spaces.

This study examines specific challenges for long-term people monitoring in public spaces and defines AI-enabled video surveillance requirements. Based on the requirements, this study proposes a CFL framework to gradually adapt AI models’ knowledge while reducing personal data transmission and retention. The framework uses three different federated learning strategies to rapidly learn from different new data sources while minimizing personal data transmission and retention to a central machine.

The findings confirm that the proposed CFL framework can help minimize the use of personal data without compromising the AI model's performance. The gradual learning strategies help develop AI-enabled video surveillance that continuously adapts for long-term deployment in public spaces.

This study makes two specific contributions to advance the development of AI-enabled video surveillance in public spaces. First, it examines specific challenges for long-term people monitoring in public spaces and defines AI-enabled video surveillance requirements. Second, it proposes a CFL framework to minimize data transmission and retention for AI-enabled video surveillance. The study provides comprehensive experimental results to evaluate the effectiveness of the proposed framework in the context of facial expression recognition (FER) which involves large-scale datasets.

To investigate the role of simulation in the introduction of technology in a continuous operations process.

A case‐based research method was chosen with the aim to provide an exemplar of practice and test the proposition that the use of simulation can improve the implementation and running of conveyor systems in continuous process facilities.

The research determines the optimum rate of re‐introduction of inventory to a conveyor system generated during a breakdown event.

More case studies are required demonstrating the operational and strategic benefits that can be gained by using simulation to assess technology in organisations.

A practical outcome of the study was the implementation of a policy for the manual re‐introduction of inventory on a conveyor line after a breakdown event had occurred.

The paper presents a novel example of the use of simulation to estimate the re‐introduction rate of inventory after a breakdown event on a conveyor line. The paper highlights how by addressing this operational issue, ahead of implementation, the likelihood of the success of the strategic decision to acquire the technology can be improved.

The traditional tissue engineering approach employs rapid prototyping systems to realise microstructures (i.e. scaffolds) which recapitulate the function and organization of native tissues. The purpose of this paper is to describe a new rapid prototyping system (PAM‐modular micro‐fabrication system, PAM²) able to fabricate microstructures using materials with different properties in a controlled environment.

Computer‐aided technologies were used to design multi‐scale biological models. Scaffolds with specific features were then designed using custom software and manufactured using suitable modules. In particular, several manufacturing modules were realised to enlarge the PAM² processing material window, controlling physical parameters such as pressure, force, temperature and light. These modules were integrated in PAM², allowing a precise control of fabrication parameters through a modular approach and hardware configuration.

Synthetic and natural polymeric solutions, thermo‐sensitive and photo‐sensitive materials can be used to fabricate 3D scaffolds. Both simple and complex architectures with high fidelity and spatial resolution ranging from ±15 μm to ±200μm (according to ink properties and extrusion module used) were realised.

The PAM² system is a new rapid prototyping technique which operates in controlled conditions (for example temperature, pressure or light intensity) and integrates several manufacturing modules for the fabrication of complex or multimaterial microstructures. In this paper it is shown how the system can be configured and then used to fabricate scaffolds mimicking the extra‐cellular matrix, both in its properties (i.e. physic‐chemical and mechanical properties) and architecture.

The purpose of this review is to provide a conceptual framework of consumer engagement behavior in the value co-creation process of healthcare services, and further understand the current knowledge maps and advances.

Specifically, the scoping review methodology is used to synthesize the extant findings. The authors first develop the inclusion/exclusion criteria to evaluate the source material for the review; then, the authors further conduct the literature refinement to select the final data sample. As such, the authors extract and analyze the information derived from these articles.

The authors found most related studies focus on exploring patients' engagement behavior in the value co-creation process, especially those with chronic disease; the findings also reveal that consumers are most likely to engage in the value co-creation process of healthcare services by seeking or sharing health information; also, consumers engagement behavior is mainly driven by individual, interactive, and technological factors; moreover, consumer engagement in the value co-creation of healthcare services are more likely to achieve positive health and behavioral outcomes.

The role of consumers has gradually shifted from that of passive recipients to that of active participants in the healthcare value co-creation process. Consumer engagement behavior is the key premise for the realization of healthcare value co-creation, and it has received increasing attention both academically and practically. By unearthing the conceptual framework of consumer engagement behavior in the value co-creation process of healthcare services, this study provides a systematic understanding and serves as a useful resource for future research and practice.