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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.

The purpose of this paper is to study the mechanical and corrosion behaviors of selective laser melting (SLM) 30CrMnSiA steel.

The microstructure, mechanical behavior and corrosion resistance of SLM 30CrMnSiA steel were studied by electrochemical test and immersion experiment.

The results showed that the microstructure of SLM 30CrMnSiA steel contained equiaxed fine (25.0 µm) ferrite and lamellar pearlite. The tensile strength of SLM 30CrMnSiA steel under the process parameters is 1,447 MPa and the elongation is 7.5%. As the immersion/salt spray test time increased to 15 days/48 h, corrosion mainly occurred in the local position of the sample and corrosion resistance decreased. When the immersion/salt spray test time increased to 30 days/168 h, the corrosion production covered the surface of the samples and the corrosion resistance increased.

The paper can guide the application and in situ repair for low-alloy steel by additive manufacturing.

This paper aims to analyse the current state of research to identify the link between Lean Manufacturing and Industry 4.0 (I4.0) technologies to map out different research themes, to uncover research gaps and propose key recommendations for future research, including lessons to be learnt from the integration of lean and I4.0.

A systematic literature review (SLR) is conducted to thematically analyse and synthesise existing literature on Lean Manufacturing–I4.0 integration. The review analysed 60 papers in peer-reviewed journals.

In total, five main research themes were identified, and a thematic map was created to explore the following: the relationship between Lean Manufacturing and I4.0; Lean Manufacturing and I4.0 implication on performance; Lean Manufacturing and I4.0 framework; Lean Manufacturing and I4.0 integration with other methodologies; and application of I4.0 technologies in Lean Manufacturing. Furthermore, various gaps in the literature were identified, and key recommendations for future directions were proposed.

The integration of Lean Manufacturing and I4.0 will eventually bring many benefits and offers superior and long-term competitive advantages. This research reveals the need for more analysis to thoroughly examine how this can be achieved in real life and promote operational changes that ensure enterprises run more sustainably.

The development of Lean Manufacturing and I4.0 integration is still in its infancy, with most articles in this field published in the past two years. The five main research themes identified through thematic synthesis are provided in the original contribution. This provides scholars better insight into the existing literature related to Lean Manufacturing and I4.0, further contributing to defining clear topics for future research opportunities. It also has important implications for industrialists, who can develop more profound and richer knowledge than Lean and I4.0, which would, in turn, help them develop more effective deployment strategies and have a positive commercial impact.

The purpose of this paper is to achieve the optimal system design of a four-wheel mobile robot on transmission line maintenance, as the authors know transmission line mobile robot is a kind of special robot which runs on high-voltage cable to replace or assist manual power maintenance operation. In the process of live working, the manipulator, working end effector and the working environment are located in the narrow space and with heterogeneous shapes, the robot collision-free obstacle avoidance movement is the premise to complete the operation task. In the simultaneous operation, the mechanical properties between the manipulator effector and the operation object are the key to improve the operation reliability. These put forward higher requirements for the mechanical configuration and dynamic characteristics of the robot, and this is the purpose of the manuscript.

Based on the above, aiming at the task of tightening the tension clamp for the four-split transmission lines, the paper proposed a four-wheel mobile robot mechanism configuration and its terminal tool which can adapt to the walking and operation on multi-split transmission lines. In the study, the dynamic models of the rigid robot and flexible transmission line are established, respectively, and the dynamic model of rigid-flexible coupling system is established on this basis, the working space and dynamic characteristics of the robot have been simulated in ADAMS and MATLAB.

The research results show that the mechanical configuration of this robot can complete the tightening operation of the four-split tension clamp bolts and the motion of robot each joint meets the requirements of driving torque in the operation process, which avoids the operation failure of the robot system caused by the insufficient or excessive driving force of the robot joint torque.

Finally, the engineering practicability of the mechanical configuration and dynamic model proposed in the paper has been verified by the physical prototype. The originality value of the research is that it has double important theoretical significance and practical application value for the optimization of mechanical structure parameters and electrical control parameters of transmission line mobile robots.

Marking and inspecting are key steps in hull structure construction. However, currently most marking and inspecting operations are still carried out manually, which leads to low assembly efficiency and quality. This paper aims to solve these problems through the application of digital technology: the optical projection and machine vision.

First, the assembly process model of hull construction is established in 3D design environment. Second, the process information is presented to workers in a virtual form through optical projector, which provides accurate guidance for the manual operation. On this basis, the workers can complete welding and assembly operations readily. Finally, the machine vision method is used to check the assembly results, which can decrease the subjective errors.

A rapid and accurate assembly positioning for hull structure construction is realized based on optical projection, which can avoid the pollution caused by the marking machine and the error caused by human.

This paper combines the advantages of optical projection and machine vision to the field of shipbuilding. The shortcomings of the traditional marking and inspection methods is effectively solved, which may provide a new way for enhancing the assembly efficiency and quality.

It is very indispensable for the various control centers of multi-transmission system owners (TSOs) grids to coordinate their reactive power optimization (RPO) efforts. However, such coordinated equilibrium point is comparatively hard to achieve unless one TSO control center could obtain all grids’ information in detail, which may lead to confidential issue and heavy communicating load. The purpose of this paper is to propose a solution to optimizing the reactive power control efforts among multi-TSOs grids with a mathematic interconnection model and reasonable communication cost.

Based on the interconnected power network equation, the stability-related optimum reactive power injection and the power-loss-related optimum reactive power injection were derived, respectively. Furthermore, according to the decomposition-and-coordination-based computing methodology, a coordinated RPO model for interconnected TSOs was designed, taking into consideration both the static voltage stability and economy.

The extreme values for the indicator L of power grid voltage stability and active power loss function were found and proved to be minimums. According to these extreme values, an expression for the reactive power injection at interconnected nodes between TSOs grids was obtained, and a coordinated strategy of RPO was established, which could take the static voltage stability and economy into consideration without confidential concern.

The existence of minimum values for indicator L of voltage stability and power loss was demonstrated, respectively. And the method presented in this paper can ensure the safety of information among different TSO grids, i.e. avoiding confidential issues. In particular, the coordinated control method can be implemented on the local power grid without knowing all of the parameters of its interconnection.

The purpose of this paper is to present a new plan approach for optimal allocation water resources in social‐economic‐environmental complex system in order to achieve human and nature coordinated development.

By integrating the system dynamics (SD) and multi‐objective programming (MOP), the new approach which is termed SD‐MOP model is proposed. The model is characterized by fully reflecting the initial trends of the system development, accurately explaining both of the structure and function of the system, objectively finding the sensible points of the system, and achieving the optimum solutions of the model, the according the solutions the optimal plan can be designed according practical situation.

By applying SD‐MOP integrated model, the designed planning proposal can be guaranteed operable, available, and optimal level.

SD‐MOP integrated model is a very useful support tool in optimal decision making.

The new planning approach of SD‐MOP integrated model can be used in regional resources planning, especially in formulating sustainable development strategies. In addition, the model can be used to estimate the trends of the system development when the planning program has been implemented.

The purpose of this paper is to examine the determinants of juvenile attitudes toward the police (JATP) in Chinese social settings. More specifically, this study borrows from the wisdom of social bond theory and relevant literature developed in the USA to explain juvenile ratings of the police on specific job functions.

The data were collected from a multi-stage cluster sample of 2,704 high school students in a city with a population of 3.8 million located in the southwest region of China. The analysis includes variables derived from social bond theory as well as traditional models commonly employed in US studies, such as demographic background and contact with the police.

The findings suggest that both social bonds and traditional models have their respective utility to explain the variation in juvenile evaluations of the police.

This study expands the scope of the investigation on JATP in China, a distinctively different cultural environment from the USA. More specifically, it explores the utility of the respective explanatory power of the social bond model and traditional models in relation to juveniles’ ratings of the police in China.

This paper aims to inspect the defects of solder joints of printed circuit board in real-time production line, simple computing and high accuracy are primary consideration factors for feature extraction and classification algorithm.

In this study, the author presents an ensemble method for the classification of solder joint defects. The new method is based on extracting the color and geometry features after solder image acquisition and using decision trees to guarantee the algorithm’s running executive efficiency. To improve algorithm accuracy, the author proposes an ensemble method of random forest which combined several trees for the classification of solder joints.

The proposed method has been tested using 280 samples of solder joints, including good and various defect types, for experiments. The results show that the proposed method has a high accuracy.

The author extracted the color and geometry features and used decision trees to guarantee the algorithm's running executive efficiency. To improve the algorithm accuracy, the author proposes using an ensemble method of random forest which combined several trees for the classification of solder joints. The results show that the proposed method has a high accuracy.

Measuring the diffusion of protests, or more generally, the diffusion of events, is an ongoing task in social sciences. This paper proposes an inter-event approach to study what types of protests tend to diffuse or decline. We develop a standardized, five-step procedure to measure what we define as “event diffusion momentum” (EDM): (1) employ event-based data containing information on the time, location, and features of each protest; (2) define the temporal and spatial ranges of interest; (3) for each observation, count the number of events before and after it within the defined ranges; (4) predict the numbers of post-event and pre-event protests with appropriate count models; (5) calculate the ratios of predicted values for each predictor and confidence intervals using the delta method. The ratio is the EDM. Applying this method to Dynamics of Collective Action (DoCA) data, we identify several micro- and macro-level factors associated with protest diffusion in the United States, 1960–1995. We conclude with the implications and generalizability of the proposed method.