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The purpose of this work is to perform an application study on experimental animals (dogs) to investigate the efficiency of using weft knitted mesh fabric as cardiac support mesh to support left ventricular hypertrophy.

In this work, weft-knitted mesh sample “Knitted Cardiac Support Mesh” manufactured using Nylon (6, 6) yarns, with count 20 Denier and medium mesh size, was placed around the two ventricles to prevent further dilatation, support and reduce left ventricular wall stress.

Medical textile is a rapidly expanding field in technical textiles that are widely used in a variety of medical applications. One of these medical textile applications is “Knitted Cardiac Support Mesh”, which is used in the treatment of Dilated Cardiomyopathy.

After the implantation of the manufactured Knitted Cardiac Support Mesh around the myocardium, all dogs survived for three months before being euthanized, and some clinical examinations were performed to investigate and evaluate the sample performance. It was demonstrated from the experimental application, that the nylon mesh sample performed the best during the surgical operation due to its good ability to stretch and recover at a moderate rate, as well as the textile mesh lightweight.

Increasingly stringent quality and cost requirements have brought about a revival in the use of stainless steel cloth as a production tool for screen printing. Process factors are examined to support the choice of stainless steel for its stability and potential for high registrational accuracy printing. Screen making is of vital importance to the end result, and the achievement and maintenance of uniform tension are as critical for stainless steel as for other screen media. Full specification of printing screen requirements is essential, as is incoming goods inspection of cloth and finished screens. The entire weaving process contributes to the overall quality of stainless steel cloth and, although post‐production correction procedures are available, they are undesirable and can be avoided by a carefully controlled weaving process.

The purpose of this study is to propose a precise and standardized strategy for numerically simulating vehicle aerodynamics.

Error sources in computational fluid dynamics were analyzed. Additionally, controllable experiential and discretization errors, which significantly influence the calculated results, are expounded upon. Considering the airflow mechanism around a vehicle, the computational efficiency and accuracy of each solution strategy were compared and analyzed through numerous computational cases. Finally, the most suitable numerical strategy, including the turbulence model, simplified vehicle model, calculation domain, boundary conditions, grids and discretization scheme, was identified. Two simplified vehicle models were introduced, and relevant wind tunnel tests were performed to validate the selected strategy.

Errors in vehicle computational aerodynamics mainly stem from the unreasonable simplification of the vehicle model, calculation domain, definite solution conditions, grid strategy and discretization schemes. Using the proposed standardized numerical strategy, the simulated steady and transient aerodynamic characteristics agreed well with the experimental results.

Building upon the modified Low-Reynolds Number k-e model and Scale Adaptive Simulation model, to the best of the authors’ knowledge, a precise and standardized numerical simulation strategy for vehicle aerodynamics is proposed for the first time, which can be integrated into vehicle research and design.

The paper reviews U‐V curable screen‐printable etch plating and solder resists, their basic components, principles of U‐V curing, their performance in the liquid as well as in the solid state and their advantages. Also discussed are the basic construction and performance of U‐V curing equipment.

This study aims to find the characteristics of supercritical airfoil in helicopter rotor blades for hovering phase using numerical analysis and the validation using experimental results.

Using numerical analysis in the forward phase of the helicopter, supercritical airfoil is compared with the conventional airfoil for the aerodynamic performance. The multiple reference frame method is used to produce the results for rotational analysis. A grid independence test was carried out, and validation was obtained using benchmark values from NASA data.

From the analysis results, a supercritical airfoil in hovering flight analysis proved that the NASA SC rotor produces 25% at 5°, 26% at 12° and 32% better thrust at 8° of collective pitch than the HH02 rotor. Helicopter performance parameters are also calculated based on momentum theory. Theoretical calculations prove that the NASA SC rotor is better than the HH02 rotor. The results of helicopter performance prove that the NASA SC rotor provides better aerodynamic efficiency than the HH02 rotor.

The novelty of the paper is it proved the aerodynamic performance of supercritical airfoil is performing better than the HH02 airfoil. The results are validated with the experimental values and theoretical calculations from the momentum theory.

This paper aims to study the influence of cylindrical texture parameters on the lubrication performance of static and dynamic pressure thrust bearings (hereinafter referred to as thrust bearings) and to optimize their lubrication performance using multiobjective optimization.

The influence of texture parameters on the lubrication performance of thrust bearings was studied based on the modified Reynolds equation. The objective functions are predicted through the BP neural network, and the texture parameters were optimized using the improved multiobjective ant lion algorithm (MOALA).

Compared with smooth surface, the introduction of texture can improve the lubrication properties. Under the optimization of the improved algorithm, when the texture diameter, depth, spacing and number are approximately 0.2 mm, 0.5 mm, 5 mm and 34, respectively, the loading capacity is increased by around 27.7% and the temperature is reduced by around 1.55°C.

This paper studies the effect of texture parameters on the lubrication properties of thrust bearings based on the modified Reynolds equation and performs multiobjective optimization through an improved MOALA.

The purpose of this paper is to optimize the key parameters (mesh count, paper type and ink type) in screen printing, which are affecting the printed ink volume. The objective of the optimization was to maximize the color reliability by decreasing the color difference (ΔE value) of the prints while minimizing the ink consumption. Screen printing is still dominating the printing industry to make cost-effective production when high volumes are needed.

The experiment was designed using the Taguchi method, and the samples were prepared with screen-printing by using the standard squeegee angle and pressure. The effect of mesh count, ink type and paper type on ink consumption was evaluated with using analysis of variances and main effects plots of S/N ratio and standard deviation.

The factors ink type, paper type and mesh count were found significant for ink consumption due to their Probability (P) values which were lower than 0.05. It was determined that the mesh count was the most critical variable with the analysis of variance. The analysis showed that the selection of an optimum mesh count was the key to controlling the amount of the deposited ink. Although mesh counts were inversely proportional with the ink consumptions, they did not affect the color differences as expected.

The optimization of process parameters, that are most effective on the print quality, is necessary to minimize the ink usage and lower the costs and environmental impact without exceeding the desired ΔE value limits.

To improve the competitiveness of the European single‐sided PCB industry as supplied to the European Consumer Electronics Industry.

This paper is intended to be of interest to those involved in electronic applications of the screen printing process, including PCBs, membrane switches, thick film printing and instrument control panels. In recent years there have been a number of advances in screen printing technology which have significantly increased the capabilities and versatility of the process. Developments have included improvements in performance of screen printing machinery, mesh fabrics, stretching equipment, screen frame design, exposure devices, stencil systems and ink rheology and printability. In spite of these advances, there are many applications in PCB production where screen printing is under‐utilised, despite its cost effectiveness for volume board production when compared with dry film resists. This paper outlines some of the developments which have produced the modern screen stencils, and describes the rôle of mesh and stencil in determining the properties of the final printed result.

Basic properties of screen materials are defined, with a study of different mesh formations and coatings and their effect on the printed image. Detailed specifications are given for a range of stainless steel, polyester, and nylon fabrics. A table then summarises recommendations for specific thick film applications such as conductor tracks, fine line conductor tracks, resistors, solder paste deposition, dielectric layers, and overglazes. The requirements for the artwork and photopositive are examined, with recommended procedures for exposing and processing the mask. The survey concludes with notes on other factors which commonly influence quality at the print stage.