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The paper's purpose is to consider a numerical study of turbulent natural convection heat transfer inside a triangular‐shaped enclosure.

In the formulation of governing non‐linear partial differential equations the momentum and energy equations coupled with a k‐ε model are applied to the enclosure. To solve these equations, a commercially available computational fluid dynamic (CFD) code, Fluent, is utilized. In addition a control volume‐based code is developed. Finally, the results are compared.

Flow and temperature field are presented as a function of aspect ratio (Ar), angle between the sloped and horizontal wall (θ) and the Grashof number (Gr). It is shown that heat transfer is higher for turbulent flow when compared with laminar flow. Meanwhile the results reflect a strong dependency on the angle between two enclosure walls (θ). It is clear from the data that the results obtained by CFD code are similar to that of control volume method.

The case considered is two‐dimensional, the motion is two‐dimensional and steady state, the flow is incompressible, the flow is Boussinesq, and the fluid properties are constant. It is recommended to conduct an experimental test in order to validate the analytical results.

The code enables the prediction of the heat transfer inside an attic‐shaped enclosure. This helps in locating the highest area of heat loss; hence prevention can be implemented for this area.

This study aims to develop a new design for the fluid-safety valve to make it more environmentally friendly.

Computational fluid dynamics is carried out to analyse the behaviour of flow in both traditional and new safety valves.

The possibility of failure in the new design under the maximum allowable working pressure is analysed using finite element analysis.

Investigating a new low-fluid pressure safety valve design.

The purpose of this study is to investigate the pulsating flow in a three-dimensional channel. Channel flow is laminar and turbulent. After validation, the effect of different channel cross-sectional geometries (circular, hexagonal and triangular) with the pulsating flow are investigated. For this purpose, the alumina nanofluid was considered as a working fluid with different volume percentages (0 per cent [pure water], 3 per cent and 5 per cent).

In this study, the pulsatile flow was investigated in a three-dimensional channel. Channel flow is laminar and turbulent.

The results show that the fluid temperature decreases by increasing the volume percentage of particles of Al₂O₃; this is because of the fact that the input energy through the wall boundary is a constant value and indicates that with increasing the volume percentage, the fluid can save more energy at a constant temperature. And by adding Al₂O₃ nanofluid, thermal performance improves in channels, but it should be considered that the use of nanofluid causes a pressure drop in the channel.

Alumina/water nanofluid with the pulsating flow was investigated and compared in three different cross-sectional channel geometries (circular, hexagonal and triangular). The effect of different volume percentages (0 per cent [pure water], 3 per cent and 5 per cent) of Al₂O₃ nanofluid on temperature, velocity and pressure are studied.

This research aims to investigate numerically the influence of braking jets on separation process of a flying object.

The flying object is at supersonic regime and axial separation of its stages is accomplished with the aid of braking jets of separated stage. The simulation is three‐dimensional and relative motion of the stages is considered three degree of freedom. Full Navier‐Stokes equations in conjunction with κ−ε (RNG) turbulence model equations are considered as governing equations. These equations are solved using the finite volume technique. The separation process is analysed as an unsteady process and the problem is solved in a moving grid domain. The local remeshing method is adapted to regenerate computational cells around moving boundaries.

Time history of flow field around the vehicle components, time history of aerodynamic coefficients, and instantaneous relative position of the body components are the results of this research. Numerical modelling results are compared with the results of other references.

Most of the similar works in this area have used Euler or thin layer Navier‐Stokes (TLNS) equations as governing equations and the use of full Navier‐Stokes equations to analyse such a complicated problem (3D axial separation with braking jets) have not been reported in the literature. Since there are some recirculation zones inside the flow field and Euler or even TLNS equations cannot predict their behaviours, the use of full Navier‐Stokes equations may lead to more accurate prediction of these regions and aerodynamic forces.

Integration of lasers and fibre optics into robotic systems provides new opportunities in sensing and material processing. Increased productivity and application of robots in hostile environments are other possibilities.

Integrating complementary information with high-quality visual perception is essential in infrared and visible image fusion. Contrast-enhanced fusion required for target detection in military, navigation and surveillance applications, where visible images are captured at low-light conditions, is a challenging task. This paper aims to focus on the enhancement of poorly illuminated low-light images through decomposition prior to fusion, to provide high visual quality.

In this paper, a two-step process is implemented to improve the visual quality. First, the low-light visible image is decomposed to dark and bright image components. The decomposition is accomplished based on the selection of a threshold using Renyi’s entropy maximization. The decomposed dark and bright images are intensified with the stochastic resonance (SR) model. Second, texture information-based weighted average scheme for low-frequency coefficients and select maximum precept for high-frequency coefficients are used in the discrete wavelet transform (DWT) domain.

Simulations in MATLAB were carried out on various test images. The qualitative and quantitative evaluations of the proposed method show improvement in edge-based and information-based metrics compared to several existing fusion techniques.

In this work, a high-contrast, edge-preserved and brightness-improved image is obtained by the processing steps considered in this work to get good visual quality.

The purpose of this study is to build a personalized learning intervention system, which can support students' personalized learning, improve teachers' teaching efficiency and students' learning effect.

The research proposes a personalized learning intervention method based on a collaborative filtering algorithm and knowledge map. The application of knowledge map makes learning content organized, and the use of collaborative filtering algorithm makes it possible to provide personalized learning recommendations for students. This personalized learning intervention system can monitor students' learning development and achieve the combination of personalized and efficiency. For the study, 152 seventh graders were assigned to a control group and an experimental group. Traditional learning intervention was used in the control group, and individualized learning intervention was used in the experimental group.

SPSS was used for data organization and analysis. The effectiveness of the personalized learning intervention system is verified by quasi-experimental research, and the influence of the system on students' learning effect is discussed. The result found that personalized learning interventions were more effective than traditional approaches in improving students’ achievement. However, for students of different learning levels, personalized learning intervention system has different effects on learning confidence and learning anxiety.

The personalized learning intervention system based on the collaborative filtering algorithm and knowledge map is effective in improving learning effect. And, it also has a certain influence on students' psychology.