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The purpose of this paper is to present a finite element analysis (FEA) of filament-wound composites, as well as application of these materials.

In this paper, a new finite element method of filament-wound composite is presented. The stress and strain fields in the composite cylinders are analyzed using the ABAQUS software packages for considering the filament undulation and crossover. The paper presented results of buckling load of composite cylinders with different types of filament-winding patterns.

The result of the example shows that the stress distributions are uniform along the cylinder length and around the circumference when the analytical approach is based on the conventional FEA. The stress distributions are not uniform along the cylinder length and around the circumference for considering the filament undulation and crossover. The stress units are arranged in a regular geometric pattern around circumference and along the axis of rotation. The analysis of the effect of filament-winding mosaic patterns on the mechanical characteristics of composite cylindrical is presented in the paper.

The stress and strain fields in the composite cylinders were analyzed for considering the filament undulation and crossover. The buckling load of composite cylinders with different types of filament-winding patterns was presented in this paper.

The influence of the number and arrangement of bolts on the tensile properties of bolted composite laminates was studied in the present study.

Based on the finite element model, the stiffness degradation method is used to simulate the damage evolution process for the failure of bolted composite laminates. Using ABAQUS finite element software combined with material failure criteria, the numerical calculation of the connection strength and failure mode of bolted composite laminates was carried out.

The results of the study show that the tensile strength of the composite laminates connected by three bolts is higher than that of the laminates connected by two bolts. And the arrangement of different bolts has a great influence on the failure strength of bolted laminates.

Bolted connection of composite laminates is a common problem in engineering practice. The effect of bolt arrangement and number on the strength of composite laminates is studied in this manuscript.

The cure simulation of composite structures with arbitrary geometry can be investigated by the finite element program.

Finite element method is employed in this work.

The simulated results match the experimental results well, which demonstrates the finite element analysis models are reliable. Compared with the one- and two-dimensional finite element analysis, temperature and degree of cure can be calculated at any point within composite structures in the present simulation analysis. The cure simulation of composite structures with arbitrary geometry can be investigated by the finite element program.

A coupled thermokinetic simulation of the liquid composite molding process based on a three-dimensional finite element method is presented. The cure simulation of composite structures with arbitrary geometry can be investigated by the finite element program.

The purpose of this study is to propose an automatic leveling method for a printing platform based on a three-point coordinate feedback. The proposed method is used in fused deposition modeling additive manufacturing systems. The coordinate error of the leveled plane is constrained to within  ± 0.2 mm, which is less than the printed layer thickness.

First, the model of the forward and inverse solutions of the parallel arm is obtained based on the principles of vector algebra. Second, the automatic leveling mechanism for collecting the z-coordinate is designed. The best position of the virtual origin plane is obtained by comparing the z-coordinates of the test points. Finally, after making multiple adjustments through a closed-loop z-coordinate feedback, the parallelism of the printing plane and the virtual origin plane is limited to an effective range.

The experimental results show that after three leveling attempts, the z-coordinate of the test points can be constrained to within  ± 0.2 mm, which shows that this method can effectively achieve automatic leveling in a delta three-dimensional (3D) printer.

This study presents a novel and distinctive delta 3D printer leveling system by designing a leveling mechanism and a leveling algorithm. The method uses a closed-loop feedback mode to make the leveling process simple, convenient and efficient without requiring major changes to the printer. The error after leveling is less than the printed layer thickness, which fully guarantees the accuracy of the leveling process.

Fault diagnosis methods based on blind source separation (BSS) for rolling element bearings are necessary tools to prevent any unexpected accidents. In the field application, the actual signal acquisition is usually hindered by certain restrictions, such as the limited number of signal channels. The purpose of this study is to fulfill the weakness of the existed BSS method.

To deal with this problem, this paper proposes a blind source extraction (BSE) method for bearing fault diagnosis based on empirical mode decomposition (EMD) and temporal correlation. First, a single-channel undetermined BSS problem is transformed into a determined BSS problem using the EMD algorithm. Then, the desired fault signal is extracted from selected intrinsic mode functions with a multi-shift correlation method.

Experimental results prove the extracted fault signal can be easily identified through the envelope spectrum. The application of the proposed method is validated using simulated signals and rolling element bearing signals of the train axle.

This paper proposes an underdetermined BSE method based on the EMD and the temporal correlation method for rolling element bearings. A simulated signal and two bearing fault signal from the train rolling element bearings show that the proposed method can well extract the bearing fault signal. Note that the proposed method can extract the periodic fault signal for bearing fault diagnosis. Thus, it should be helpful in the diagnosis of other rotating machinery, such as gears or blades.

The purpose of this paper is to explore financial quality problems, based on the dynamics of the ownership structure, in the privatization process to clarify the internal relation among the ownership’s attribution of the commercial mixed ownership company, the company’s performance and its financial relationships. This paper also examines the mixed ownership enterprise’s potential problems during the development process.

Adopting the single case study method, the authors selected the mixed ownership public company Hubei Sanxia New Building Materials Co., Ltd. (stock code: 600293) to explore, from a privatization perspective, the impact of mixed ownership on financial quality.

The study found that Sanxia experienced tight cash flow and heavy debt burdens due to the privatization and that its controlling shareholders used non-operating income to support Sanxia, thus characterizing the dual role of “the grabbing hand” and “the helping hand.” Sanxia’s privatization process highlighted the volatility of performance, the exception of monetary funds and the existence of accounting fraud rather than the prosperous development of the capital combination.

These findings provided case support that privatization negatively affects the financial quality of the company. Previous studies have indicated that there should be greater focus more on the issue that state-owned shares rebound during the process of privatization and that, with respect to commercial mixed ownership reform of state-owned enterprises, such reform must avoid the passive transfer of corporate control, ensure the fairness of the related transactions, prevent the loss of state-owned assets and preclude the controlling shareholders from seizing interests of listed companies.

The purpose of this paper is to improve the corrosion resistance of the 6061-Al alloy as the battery pack material for electric vehicles, and the nano-SiC/MAO composite coating was prepared.

The corrosion resistance of coatings was evaluated by the global electrochemical test, and the local electrochemical impedance spectroscopy (LEIS) was used to study the local corrosion mechanism. The laser confocal microscope, scanning electron microscope and X-ray diffractometer (XRD) were used to characterise coatings.

Results showed that the impedance of nano-SiC/MAO coating was 1–2 times higher than MAO coating, and the main corrosion product was Al(OH)₃. LEIS results showed that the impedance of the nano-SiC/MAO coating was two times higher than the MAO coating. The defective SiC/Micro-arc oxidation coating still had high corrosion resistance compared to the MAO coating.

The physical model of the local corrosion mechanism for SiC/MAO composite coating in “cavity-fracture collapse” mode was proposed.