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The purpose of this paper is to study the effect of current-carrying condition on the electrochemical process and atmospheric corrosion behavior of the commercial aluminum alloys.

Potentiodynamic polarization tests were performed to study the electrochemical process of the aluminum alloys. Salt spray tests and weight loss tests were carried out to study the atmospheric corrosion behavior. The corrosion morphology of the alloys was observed, and the products were analyzed.

The corrosion process of four aluminum alloys was accelerated in the current-carrying condition. Moreover, the acceleration effect on A2024 and A7075 was much stronger than that on A1050 and A5052. The main factors would be the differences in microstructure and corrosion resistance between these alloys. As the carried current increased, the corrosion rate and corrosion current density of the aluminum alloys gradually increased, with the protection of the corrosion product film decreasing linearly.

This is a recent study on the corrosion behavior of conductors under current-carrying condition, which truly understands the corrosion status of power grid materials. Relevant results provide support for the corrosion protection and safe service of aluminum alloy in power systems.

Surface roughness has a serious impact on the fatigue strength, wear resistance and life of mechanical products. Realizing the evolution of surface quality through theoretical modeling takes a lot of effort. To predict the surface roughness of milling processing, this paper aims to construct a neural network based on deep learning and data augmentation.

This study proposes a method consisting of three steps. Firstly, the machine tool multisource data acquisition platform is established, which combines sensor monitoring with machine tool communication to collect processing signals. Secondly, the feature parameters are extracted to reduce the interference and improve the model generalization ability. Thirdly, for different expectations, the parameters of the deep belief network (DBN) model are optimized by the tent-SSA algorithm to achieve more accurate roughness classification and regression prediction.

The adaptive synthetic sampling (ADASYN) algorithm can improve the classification prediction accuracy of DBN from 80.67% to 94.23%. After the DBN parameters were optimized by Tent-SSA, the roughness prediction accuracy was significantly improved. For the classification model, the prediction accuracy is improved by 5.77% based on ADASYN optimization. For regression models, different objective functions can be set according to production requirements, such as root-mean-square error (RMSE) or MaxAE, and the error is reduced by more than 40% compared to the original model.

A roughness prediction model based on multiple monitoring signals is proposed, which reduces the dependence on the acquisition of environmental variables and enhances the model's applicability. Furthermore, with the ADASYN algorithm, the Tent-SSA intelligent optimization algorithm is introduced to optimize the hyperparameters of the DBN model and improve the optimization performance.

The purpose of this paper is to introduce a motion control method for WFF-AmphiRobot, which can effectively realize the flexible motion of the robot on land, underwater and in the transition zone between land and water.

Based on the dynamics model, the authors selected the appropriate state variables to construct the state space model of the robot and estimated the feedback state of the robot through the maximum a posteriori probability estimation. The nonlinear predictive model controller of the robot is constructed by local linearization of the model to perform closed-loop control on the overall motion of the robot. For the control problem of the terminal trajectory, using the neural rhythmic movement theory in bionics to construct a robot central pattern generator (CPG) for real-time generation of terminal trajectory.

In this paper, the motion state of WFF-AmphiRobot is estimated, and a model-based overall motion controller for the robot and an end-effector controller based on neural rhythm control are constructed. The effectiveness of the controller and motion control algorithm is verified by simulation and physical prototype motion experiments on land and underwater, and the robot can ideally complete the desired behavior.

The paper designed a controller for WFF-AmphiRobot. First, when constructing the robot state estimator in this paper, the robot dynamics model is introduced as the a priori estimation model, and the error compensation of the a priori model is performed by the method of maximum a posteriori probability estimation, which improves the accuracy of the state estimator. Second, for the underwater oscillation motion characteristics of the flipper, the Hopf oscillator is used as the basis, and the flipper fluctuation equation is modified and improved by the CPG signal is adapted to the flipper oscillation demand. The controller effectively controls the position error and heading angle error within the desired range during the movement of the WFF-AmphiRobot.

The purpose of this study is to simultaneously investigate a comprehensive analysis of the extent to which strategic orientations, namely, imitation and innovation orientations, and knowledge management affect firm performance.

Drawing on the theoretical frameworks of the resource-based view and dynamic capability theory, this scholarly inquiry has proposed a comprehensive framework that delineates the relationships amongst imitation, innovation, absorptive capacity (ACAP), innovation performance and financial performance. To scrutinize the proposed research model, bootstrap routines were used through Smart partial least squares to estimate the procedures. To collect the necessary data, a questionnaire and financial statements were acquired from a sample of 100 Iranian firms listed on the Tehran Stock Exchange. The findings of the study have important implications for both scholars and practitioners seeking to enhance firm performance through the effective utilization of imitation, innovation and ACAP.

The results indicate that imitation activities have directly led to the improvement in innovation performance, even in the presence of innovation and ACAP. However, the relationship has not been confirmed by financial performance.

Imitation and innovation orientations have been identified as pivotal strategic orientations that can significantly affect firm performance. As far as the authors know, this investigation represents the first comprehensive examination of both imitation and innovation activities as a critical transition in emerging markets (EMs) characterized by complex economies, such as Iran. The findings may aid firms in enhancing their performance by providing insight into the strategic importance of imitation and innovation orientations in EMs.

According to extensive analysis, employee agility is influenced by teamwork, coordination and the organizational environment. However, less consideration has been given to the role of work stressors (challenge, hindrance) in influencing employee agility. To address this research gap, this study sheds light on how the use of enterprise social media (ESM) for social and work purposes influences employee agility through work stressors.

This research also explores how ESM visibility enhances the interaction between work stressors and employee agility by using primary data obtained from Chinese workers. A total of 377 entries were analyzed using AMOS 24.10 tools. All the hypotheses were tested using structural equation modeling (SEM).

The findings revealed that ESM use (social and work) negatively impacts challenge and hindrance work stressors. The results also reflect that challenge stressors have a significant impact on employee agility, whereas hindrance stressors are negatively related to it. Furthermore, the outcome also indicated that increased ESM visibility reinforces the connection between challenge stressors and employee agility. However, ESM visibility did not indicate a significant moderating impact on the link between hindrance stressors and employee agility.

This study describes how ESM usage effects agility of stressed employees. This research also explores how ESM visibility improves the interaction between work stressors and employee agility. The study results contribute to growing research on social media and employee agility and suggest several points of guidance for managers.

As a common form of failure in industry, corrosion causes huge economic losses. At present, with the development of computational techniques, artificial intelligence (AI) is playing a more and more important role in the field of scientific research. This paper aims to review the application of AI in corrosion protection research.

In this paper, the role of AI in corrosion protection is systematically described in terms of anticorrosion materials and methods, corrosion image recognition and corrosion life prediction.

With efficient and in-depth data processing methods, AI can rapidly advance the research process in terms of anticorrosion materials and methods, corrosion image recognition and corrosion life prediction and save on costs.

This paper summarizes the application of AI in corrosion protection research and provides the basis for corrosion engineers to quickly and comprehensively understand the role of AI and improve production processes.

How to identify the critical success factors (CSFs) of public health emergencies (PHEs) is of great practical significance to carry out a scientific and effective risk assessment. The purpose of this paper is to address this issue.

In this paper, the authors propose a new approach to identify the CSFs by hesitant fuzzy linguistic set and a Decision-Making Trial and Evaluation Laboratory (DEMATEL) approach. First, a larger group of experts are clustered into three groups according to similarity degree. Then, the weight of each cluster is determined by the maximum consensus method, and the overall direct influence matrix is obtained by clustering with hesitant fuzzy linguistic weighted geometric (HFLWG) operators. Finally, the overall direct influence matrix is transformed into the crisp direct impact matrix by the score function, and 11 CSFs of PHEs are identified by using the extended DEMATEL method.

In addition, an example of PHEs shows that the approach has good identification applicability. The approach can be used to solve the problems of fuzziness and subjectivity in linguistic assessments, and it can be applied to identify the customer service framework with the linguistic assessments process in emergency management.

This paper extends the above DEMATEL method to study in the hesitant fuzzy linguistic context. This proposed hybrid approach has a wider application in the high-risk area where disasters frequently occur.

Quality awards are widely considered symbols of successful quality management. The purpose of this paper is to empirically test the effects of the China Quality Award (CQA) on firms' performance. The study further explores how the benefits due to CQA are affected by contextual factors.

Using the data of CQA winners from 2001 to 2016, the event study method is applied to analyze the abnormal performance of winners. Furthermore, multiple regression models are proposed to evaluate the effects of contextual factors on the relationship between the award and profitability.

The findings show that CQA has positive impacts on profitability and fixed asset efficiency but not on labor productivity. Besides, state-owned firms and firms with high innovation intensity obtain more profitability benefits than others.

This is the first study to explain the relationship between quality awards and firm performance from a theoretical perspective, providing new insights into the quality management and performance literature. Furthermore, this study deepens the understanding of the relationship between quality awards and performance and reveals new implications. Some of the contextual factors examined, such as innovation intensity, are considered for the first time in quality award research.

As China shifts from a “human capital demographic dividend” to a “demographic dividend” as a source of economic growth, this paper examines the influence of social security system improvement on enterprises efforts to attract talent and enhance innovation ability.

This study uses a sample of Chinese listed firms from 2008 to 2019 to analyse the influences of social security contributions on enterprise innovation, and the mediating effect of human capital accumulation. The OLS, DID test, placebo test, 2SLS are used to test the research questions.

The authors find a significant positive correlation between social security contributions and enterprise innovation because social security contributions improve the accumulation of human capital, helping enterprises to attract talent, which in turn has a positive impact on corporate innovation. The positive correlation between social security contributions and enterprise innovation is more significant in private enterprises, STAR Market and GEM listed companies and labour-intensive enterprises.

These findings provide a theoretical basis for the formulation of relevant policies and the current reform of social security collection in China. The findings also have practical significance for the sustainable development of China's economy given its ageing population.

This study provides a new perspective, that is, from the perspective of human capital accumulation, to discuss the impact of social security contributions on enterprise innovation, and enriches the relevant literature on the economic consequences of social security contributions and the influencing factors of corporate innovation.

This chapter examines the impacts of scheduled announcements of 14 widely followed macroeconomic news on the corporate bond market from July 2002 to June 2017 and documents several new findings. First, good (bad) macroeconomic news tends to have a negative (positive) effect on IG bond returns and a positive (negative) effect on high-yield (HY) bond returns. Second, nonfarm payroll (NFP) appears to be the “King of announcements” for the corporate bond market. Third, while information about revisions of prior releases is incorporated into bond prices on announcement days, future revisions fail to be priced in. Fourth, the news information is thoroughly and quickly reflected in bond prices on the announcement day. Finally, corporate bond volatility increases on announcement days, whereas the Zero Lower Bound (ZLB) policy has little effect on conditional volatility.