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The defect detection problem of color-patterned fabric is still a huge challenge due to the lack of manual defect labeling samples. Recently, many fabric defect detection algorithms based on feature engineering and deep learning have been proposed, but these methods have overdetection or miss-detection problems because they cannot adapt to the complex patterns of color-patterned fabrics. The purpose of this paper is to propose a defect detection framework based on unsupervised adversarial learning for image reconstruction to solve the above problems.

The proposed framework consists of three parts: a generator, a discriminator and an image postprocessing module. The generator is able to extract the features of the image and then reconstruct the image. The discriminator can supervise the generator to repair defects in the samples to improve the quality of image reconstruction. The multidifference image postprocessing module is used to obtain the final detection results of color-patterned fabric defects.

The proposed framework is compared with state-of-the-art methods on the public dataset YDFID-1(Yarn-Dyed Fabric Image Dataset-version1). The proposed framework is also validated on several classes in the MvTec AD dataset. The experimental results of various patterns/classes on YDFID-1 and MvTecAD demonstrate the effectiveness and superiority of this method in fabric defect detection.

It provides an automatic defect detection solution that is convenient for engineering applications for the inspection process of the color-patterned fabric manufacturing industry. A public dataset is provided for academia.

This study aims to understand the multiaxial fretting fatigue, wear and fracture characteristics of 35CrMoA steel under the elliptical loading path.

By keeping the contact pressure and torsional shear cyclic stress amplitude unchanged; the axial cyclic stress amplitude varied from 650 MPa to 850 MPa. The fretting fatigue test was carried out on MTS809 testing machine, and the axial cyclic strain response and fatigue life of the material were analyzed. The fretting zone and fracture surface morphology were observed by scanning electron microscope. The composition of wear debris was detected by energy dispersive X-ray spectrometer.

In this study, with the increase of axial stress amplitude, 35CrMoA steel will be continuously softened, and the cyclic softening degree increases. The fretting fatigue life decreases unevenly. The fretting scars in the stick region are elongated in the axial direction. The area of fracture crack propagation zone decreases. In addition, the results indicate that wear debris in the slip region is spherical and has higher oxygen content.

There were few literatures about the multiaxial fretting fatigue behavior of 35CrMoA steel, and most scholars focused on the contact pressure. This paper reveals the effect of axial cyclic stress on fretting fatigue and wear of 35CrMoA steel under the elliptical loading path.

The purpose of this paper is to understand the effect of particle content, applied load and sliding speed on the tribological properties of A356-SiCP composites manufactured using a newly developed vacuum stir casting technique.

A356 alloy reinforced with 10, 15 and 20 vol% SiC particles was prepared by vacuum stir casting. Tribological tests were carried out on block-on-ring tribometer under dry sliding conditions, room temperature. Wear mechanism was investigated by scanning electron microscope and energy dispersion spectrum.

SiCP is homogeneously dispersed in the matrix. The increase in SiCP content decrease wear rate, but it leads to an increase in coefficient of friction. The wear rate increase and friction coefficient present different variation trends with increasing load. For A356-20%SiCP composite, when the load is less than 10 MPa, wear rate and friction coefficient under sliding speed of 400 rpm are lower than those of 200 rpm. Wear mechanism transition from abrasion, oxidation, delamination, adhesion to plastic flow as load and sliding speed increasing.

Results of this study will help guide the use of A356-SiCP in many automotive products such as brake rotors, brake pads, brake drums and pistons.

There are few paper studies the effect of particle content, applied load and sliding speed on the tribological properties of A356-SiCP composites. Aluminum matrix composites with uniform distribution of reinforcing particles were successfully prepared by using the newly developed vacuum stir casting technique.

The purpose of this paper is to investigate the time-varying finite-time formation tracking control problem for multiple unmanned aerial vehicle systems under switching topologies, where the states of the unmanned aerial vehicles need to form desired time-varying formations while tracking the trajectory of the virtual leader in finite time under jointly connected topologies.

A consensus-based formation control protocol is constructed to achieve the desired formation. In this paper, the time-varying formation is specified by a piecewise continuously differentiable vector, while the finite-time convergence is guaranteed by utilizing a non-linear function. Based on the graph theory, the finite-time stability of the close-loop system with the proposed control protocol under jointly connected topologies is proven by applying LaSalle’s invariance principle and the theory of homogeneity with dilation.

The effectiveness of the proposed protocol is verified by numerical simulations. Consequently, the proposed protocol can successfully achieve the predefined time-varying formation in finite time under jointly connected topologies while tracking the trajectory generated by the leader.

This paper proposes a solution to simultaneously solve the control problems of time-varying formation tracking, finite-time convergence, and switching topologies.

The purpose of this paper was to examine the relationship between organizational tenure and employee innovative behavior and the influence of culture difference and status-related moderators (i.e. status hierarchy and status stability) on the linkage.

By using a meta-analysis method that included 76 empirical studies, this study examines the relationship of organizational tenure and innovative behavior. In this study, 79 samples (N = 21659) derived from 76 empirical studies that met the inclusion criteria in the meta-analysis.

The results show that organizational tenure has a weak positive effect on employee innovative behavior (r = 0.04), and status hierarchy, position tenure, culture difference and measurement ways influence the relationship between the two. In addition, a three-way interaction among status hierarchy, position tenure and organizational tenure is found to jointly affect innovative behavior; specifically, for those who are low in status hierarchy and short in position tenure, their organizational tenures are positively related to innovative behavior, but for those with a longer position tenure in organizations, their organizational tenure may relate to innovative behavior negatively, whatever their status hierarchies are (high or low). This study is helpful in providing theoretical foundation and practical skills to such issues regarding how to trigger innovative behavior efficiently at different career stages.

Limitations include tenure range of participants and no longitudinal samples in our studies. Future research should examine more contextual factors which influenced the relationship between organizational tenure and innovative behavior.

The results of this study show that long organizational tenure is not negatively related to innovative behaviors. For managers, do not ignore the contribution of long-tenured employees to innovation. Through promotion or job rotation to increase employees’ job satisfaction and innovative willing.

To authors’ knowledge, this is the first study to examine status attribute class variables in the relationship between organizational tenure on innovative behavior. The study is helpful in providing theoretical foundation and practical skills to such issues regarding how to trigger innovative behavior at different career stages correctly.

Guided by social exchange theory and signaling theory, this chapter investigates the relationship between individual perceptions of high-performance work systems (HPWS), union instrumentality, and employees’ turnover intention. The results obtained from a multilevel and multisource sample of more than 1,300 employees in 37 multinational corporation based in China show that, in contrast to our hypothesis, union instrumentality is not directly related to turnover intention; rather, the results from the post hoc mediation analysis show that union instrumentality is indirectly and negatively related to turnover intention through affective organizational commitment. Consistent with our hypothesis, the results of our analysis show that union instrumentality serves as an important contingent factor in the relationship between HPWS and employee turnover intention. The relationship between HPWS and turnover intention becomes positive when employee union instrumentality is low.

The purpose of this paper is to provide theoretical basis and data support for researchers to choose appropriate international partners, provide a basis for Chinese research funding agencies, such as National Natural Science Foundation of China (NSFC) to formulate international research collaboration (IRC) strategies and policies and provide recommendations for the improvement of the internationalization level of China's basic scientific research.

Based on existing research, this study took output of “Major International (Regional) Joint Research Project” (MIJRP) funded by NSFC and participated by Chinese scholars in the meantime as the analysis object, proposed hypotheses and constructed the indicators of IRC and research output (RO). In addition, the mathematical statistics was used to compare the RO of China's IRC and nonIRC, and the statistical analysis model was used to measure the influence on RO of collaboration country's research capacity, research collaboration between China and US, scope of international research collaboration and reprint author country.

The RO of China's IRC is higher than that of nonIRC; research capacity of collaboration country has no inevitable effect on the RO of China's IRC; the RO of China's IRC participated by Americans is higher than that without American scholars; expanding the scope of China's IRC to some degree can increase RO; the RO of China's IRC led by foreigners is higher than that led by Chinese. In particular, China–US IRC and foreign scholars acting as the reprint author are two major factors for the RO of China's IRC.

Most of the traditional research on IRC are based on the co-author papers, and this study tried to analyze the characteristics and regularities on IRC from a new view of international collaboration projects, which can be a supplement to the traditional international collaboration research on co-author papers.

To improve the high-temperature wear properties of the SiCp/A359 composite, foamed iron-reinforced SiCp/A359 composite (A359–SiCp/Fe) is prepared. The purpose of this study is to investigate the tribological behavior and mechanism of the A359–SiCp/Fe composites at different temperatures (100–500 °C) and loads (7 N, 10 N and 12 N).

The A359–SiCp/Fe composite was fabricated by vacuum-assisted infiltration. The dry sliding tribological behaviors of A359–SiCp/Fe composite were investigated using the ball-on-disc-type tribometer. The worn surface and wear morphology of the longitudinal section were examined using field emission scanning electron microscopy and metallographic microscope.

The critical transition temperature for severe wear in A359–SiCp/Fe composite was 50–100 °C higher than in SiCp/A359 composite. Foamed iron prevents exfoliation cracks from penetrating deeper into the matrix. The friction coefficient stability of the A359–SiCp/Fe composite was higher than the unreinforced composite at elevated temperatures. With the increase in temperature, the friction-affected layer was severely worn, and the wear mechanism transferred from abrasion and delamination to oxidation and plastic flow, respectively.

The preparation procedure for aluminum matrix composites reinforced with foamed metal has been less reported, and the research on the tribological behavior and mechanism of A359–SiCp/Fe composite at various temperatures is insufficient. The foamed iron structure considerably enhances the wear properties of SiCp/A359 composite in elevated temperature conditions.

To investigate transverse vibration of the eccentric rotor in a 12/8 poles switched reluctance motor (SRM), a transverse analytical vibration model is built by finite element method (FEM) under the interaction of radial magnetic resultant and vibration displacement. External forces, including radial magnetic resultant and centrifugal force, are also derived in detail, according to the variation of airgap and current and other intermediate parameters with rotation angle.

The transverse vibration response of the eccentric rotor including radial magnetic resultant and vibration displacement is solved by Newmark-β method, after inputting the currents of three phase windings under angle position control strategy. The basic characteristics of radial magnetic resultant and vibration displacement are reflected in time and frequency domain.

The magnetic resultant vector of the eccentric rotor presents multi-petals star geometric shape. The frequency distribution of magnetic resultant relates to rotation speed, current waveform and the least common multiple of the stator and rotor teeth. However, the frequency distribution of the vibration displacement also relates closely to the first-order critical whirl speed of the rotor. When the rotor is running at certain speeds, it will display superharmonic resonance and show abundant displacement locus.

By using this analytical model and solving process proposed in this paper, the nonlinear coupled vibration response of the eccentric rotor in SRM can be analyzed and discussed rapidly; only the stator’s winding currents obtained by experiment or electromagnetic simulation is needed as input.

This paper aims to investigate the effect of Cu content and T6 heat treatment on the mechanical properties and the tribological performance of SiCp/Al-Si-Cu-Ni-Mg hybrid composites at an elevated temperature.

The stir casting method was used to synthesize SiCp/Al-12Si-xCu-1Ni-1Mg (x = 2, 3, 3.5, 4, 4.5, 5 Wt.%) composites containing 20 vol% SiC. The hardness and tensile strength of the aluminum matrix composites (AMCs) at room temperature and elevated temperature were studied, and the wear mechanism was investigated using scanning electron microscopic and energy dispersive spectroscopy.

Results indicate that the hardness and tensile strength of the AMCs are affected significantly by T6 heat treatment and Cu content. The high-temperature friction and wear mechanism of AMCs is the composite wear mechanism of oxidation wear, adhesion wear, abrasive wear, peeling wear, high-temperature softening and partial melting. Among them, adhesion wear, high-temperature matrix softening and local melting are the main wear mechanisms.

The influence mechanism of Cu content on the hardness, tensile strength and high temperature resistance of AMCs was explained by microstructure. And the results further help to explore the application of AMCs in high temperature.