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This study investigated the building energy, glare and daylight performance of overhang using building simulation software Energyplus in order to identify an optimal depth in hot summer and cold winter zone. A typical building with different window-to-wall ratios (WWR) was modeled and different overhang depths were considered. Results showed that the optimal overhang depths are 0.9m (WWR=0.15), 1.16m (WWR=0.3) and 1.62m (WWR=0.57), respectively. The total energy savings from overhang design can be ranging from about 3% to 24% depending on WWR and overhang depth. Moreover, the regression relationship between optimal overhang depth and WWR is given to help identify the best overhang dimension at the design stage. The potential energy saving performance for different WWRs then can be roughly inferred according to a total energy saving chart without building energy simulation. In conclusion, to be applicable in buildings, an overhang depth of 0.6-0.8m is suitable in this region since it has a balance in energy performance and aesthetic appearance.

Surface texturing has been proven as an effective means of contact performance enhancement. However, limited work has been done to investigate the regular relationship to solve the multi-parameters problem of textures, and inertia effect and elastic deformation were seldom considered together in previous optimization work. This paper aims to quantitatively obtain the relationship between the textured depth and liquid film thickness and find the effect of deformation on the optimal textured height ratio in elastic parallel sliders.

Numerical models of hydrodynamic lubrication are established based on the computational fluid dynamic method. Elastic deformation is considered through fluid–structure interaction (FSI) method. Using response surface optimization method, textured parallel sliders are optimized with maximum loading capacity as the objective.

The results show that the optimal height ratios are all within the range of 0.60-0.65 when textured parallel sliders are considered as rigid. After considering the effect of elastic deformation, loading capacity drops and is reduced more obviously with a decrease in the elastic moduli. The optimal height ratios are within the range of 0.60-0.63, which shows that FSI has a considerable influence on loading capacity but has no significant influence on the optimal height ratio.

The present research provides a theoretical reference for engineering application of elastic textured parallel sliders.

To avoid the structural defect, early crack detection is oneof the important aspects in the recent area of research. The purpose of this paper is to detect the crack before its failure by means of its position and severity.

This paper uses two trees based regressors, namely, decision tree (DT) regressor and random forest (RF) regressor for their capabilities to adopt different types of parameter and generate simple rules by which the method can predict the crack parameters with better accuracy, making it possible to effectively predict the crack parameters such as its location and depth before failure of the beam.

The predicted parameters can be achieved, if the relationship between vibration and crack parameters can be attained. The relationship yields the results of beam natural frequencies, which is used as the input value for the regression techniques. It is observed that the RF regressor predicts the parameters with better accuracy as compared to DT regressor.

The idea is used the developed regression techniques to identify the crack parameters which are more effective as compared to other developed methods because the alternate name of prediction is called regression. The authors have used DT regressor and RF regressor to achieve the target. In this paper care has been given to the generalization of the model, so that the adaptability of the model can be ensured. The robustness of proposed methods has been verified in support of numerical and experimental analysis.

The purpose of this study is to present a depth information-based solution for automatic camera control, depending on the presenter’s moving positions. Talks, presentations and lectures are often captured on video to give a broad audience the possibility to (re-)access the content. As presenters are often moving around during a talk, it is necessary to steer recording cameras.

We use depth information from Kinect to implement a prototypical application to automatically steer multiple cameras for recording a talk.

We present our experiences with the system during actual lectures at a university. We found out that Kinect is applicable for tracking a presenter during a talk robustly. Nevertheless, our prototypical solution reveals potential for improvements, which we discuss in our future work section.

Tracking a presenter is based on a skeleton model extracted from depth information instead of using two-dimensional (2D) motion- or brightness-based image processing techniques. The solution uses a scalable networking architecture based on publish/subscribe messaging for controlling multiple video cameras.

The purpose of this paper is to present a new concept of passive loop technique called “high magnetic coupling passive loop” (HMCPL) (suitable for buried power lines) along with optimised design parameters.

The optimal design (geometrical displacement and shielding current intensity and phase) for the mitigation of magnetic field produced by flat and trefoil configuration of the power line is carried out by means of genetic algorithm.

Different layouts for the source (flat and trefoil configuration) and the shield (introduction of the phase splitting technique) are designed. The optimization parameters are the coordinates of the shield conductors and the transformer ratio of the magnetic core that couple the source and the shield. Moreover, physical constraints as maximum depth of excavation and geometric interference between cables were introduced in the optimization procedure.

The paper deals with a very new technology for field mitigation called HMCPL. Actually, the base layout of the HMCPL does not need an optimal design. On the other hand, in some applications the base layout cannot be used, therefore, the introduction of an optimal design cannot be avoided. In this paper, the optimal design of several configurations is performed showing that the performances of the HMCPL are very interesting even if the base layout cannot be used.

The main purpose of this paper is to understand and model the hydrodynamic influence of surface textures on journal bearings.

In the model, a rectangular array of circle dimples is used to modify the film thickness expression. In full film and cavitation regions, classical Reynolds equation and Reynolds boundary condition are used as the governing equations, respectively. By setting high load bearing capacity as the main optimal goal, the influence of textures on tribological characteristics is studied to get the optimal distribution and parameters of textures.

The results suggest that the load bearing capacity of a journal bearing may be improved through appropriate arrangement of textures partially covering its sleeve. The reduction of the cavitation area may also be achieved by arranging the textures in divergent region. With a high density distribution of textures which have step depths varying linearly along the circumferential direction of the bearing, the load bearing capacity enhancement seems to give good performance. Comparing with smooth bearing, the load bearing capacity enhancement of such textures is about 56.1 per cent, although the influence of texture diameters for the same area density seems insignificant.

The paper shows how surface textures can be designed on journal bearing to improve its tribological performances.

This study aims to investigate the effects of irregular groove textures on the friction and wear performance of sliding contact surfaces. These textures possess multiple depths and asymmetrical features. To optimize the irregular groove texture structure of the sliding contact surface, an adaptive genetic algorithm was used for research and optimization purposes.

Using adaptive genetic algorithm as an optimization tool, numerical simulations were conducted on surface textures by establishing a dimensionless form of the Reynolds equation and setting appropriate boundary conditions. An adaptive genetic algorithm program in MATLAB was established. Genetic iterative methods were used to calculate the optimal texture structure. Genetic individuals were selected through fitness comparison. The depth of the groove texture is gradually adjusted through genetic crossover, mutation, and mutation operations. The optimal groove structure was ultimately obtained by comparing the bearing capacity and pressure of different generations of micro-convex bodies.

After about 100 generations of iteration, the distribution of grooved textures became relatively stable, and after about 320 generations, the depth and distribution of groove textures reached their optimal structure. At this stage, irregular texture structures can support more loads by forming oil films. Compared with regular textures, the friction coefficient of irregular textures decreased by nearly 47.01%, while the carrying capacity of lubricating oil films increased by 54.57%. The research results show that irregular texture structures have better lubrication characteristics and can effectively improve the friction performance of component surfaces.

Surface textures can enhance the friction and lubrication performance of metal surfaces, improving the mechanical performance and lifespan of components. However, surface texture processing is challenging, as it often requires multiple experimental comparisons to determine the optimal texture structure, resulting in high trial-and-error costs. By using an adaptive genetic algorithm as an optimization tool, the optimal surface groove structure can be obtained through simulation and modeling, effectively saving costs in the process.

This study aims to enhance the lubrication performance of thrust bearings. The influence of columnar convex–concave compound microtexture on bearing performance is investigated

Based on the compound microtexture model of thrust bearings, considering surface roughness and turbulent effect, the variation of lubrication characteristics with the change in the compound microtexture parameters is studied.

The results indicate that, compared with circular microtexture, the maximum pressure of compound microtexture of thrust bearings increases by 7.42%. Optimal bearing performance is achieved when the internal microtexture depth is 0.02 mm. Turbulent flow states and surface roughness lead to a reduction in the optimal depth. The maximum pressure and load-carrying capacity of the bearing decrease as the initial angle increases, whereas the friction coefficient increases with the increase in the initial angle. The lubrication performance is best for bearings with a circumferential parallel arrangement of microtexture.

The novel composite microtexture with columnar convex-concave is proposed, and the computational model of thrust bearings is set. The influence of surface roughness and turbulent flow on the bearing performance should be considered for better conforming with engineering practice. The effect of microtexture depth, arrangement method and distribution position on the lubrication performance of the compound microtexture thrust bearing is investigated, which is of great significance for improving tribology, thrust bearings and surface microtexture theory.

Surface roughness is an important parameter in manufacturing engineering with significant influence on the performance of mechanical parts. Failures, sometimes catastrophic failures, leading to high costs, have been imputed to a component's surface roughness. Owing to the need for improvement of machining parameters in order to obtain a prescribed surface roughness, new developments have been recently investigated. This work aims to report on a study of an optimisation model based on genetic algorithms (GAs).

The developed algorithm considers a machining parameter data population obtained from experimental tests. The exchange of structured information based on natural selection principles and “survival‐of‐the‐fittest” allows the combination of solutions in a sequence of generations leading to the best solution.

Over standard experimental design methodologies the proposed GA approach shows advantages in finding the optimal conditions under the imposed constraints. Indeed the quality of the produced surface roughness cannot be evaluated using only a criterion. This GA method determines the combined effects of the input parameters to the optimal machining parameter.

A new methodology for determining optimal machining parameters in dry turning based on the measurement of the surface roughness is proposed. The numerical and experimental developed model can be used with success on further applications with industrial interest.

This study aims to explore the superiority of the compound dimple (e.g. the rectangular-rectangular dimple) and compare its tribological performance for rough parallel surfaces with those of the traditional one-layer dimple (simple dimple).

A mixed-lubrication model for a rough textured surface is established and solved using the finite difference method for film pressure and contact pressure. To accelerate the evaluation of surface deformation, the efficient Continuous convolution fast Fourier transform algorithm is applied. The effects of the compound dimple on the tribological performance for the rough parallel surfaces is numerically investigated. And these effects are compared with those of the simple dimple. Furthermore, a reciprocating friction test is conducted to verify the superiority of the compound dimple.

The compound dimple exhibits better tribological performances in comparison with the traditional simple dimple, that is, a larger load-carrying capacity and a smaller friction coefficient. To achieve the best tribological performances for the rough parallel surfaces, the depth ratio of the lower pore to the total pore of the compound dimple and the dimple interval should be reasonably chosen. For the surface with compound dimples, there exists an optimal surface roughness to simultaneously maximize the load-carrying capacity and minimize the friction coefficient. The smaller friction coefficient of the surface with compound dimples is verified by the reciprocating friction test.

The compound dimple is proposed and the superiority of this novel surface texture is confirmed. This study is expected to provide a new texturing method to improve the tribological performances of the traditional simple dimple.