Search results

The weld joint of large thin-wall metal parts which deforms in manufacturing and clamping processes is very difficult to manufacture for its shape is different from the initial model; thus, the space normals of the part surface are uncertain.

In this paper, an effective method is presented to calculate cutter location points and to estimate the space normals by measuring some sparse discrete points of weld joint. First, a contact-type probe fixed in the end of friction stir welding (FSW) robot is used to measure a series of discrete points on the weld joint. Then, a space curve can be got by fitting the series of points with a quintic spline. Second, a least square plane (LSP) of the measured points is obtained by the least square method. Then, normal vectors of the plane curve, which is the projection of the space curve on the LSP, are used to estimate the space normals of the weld joint curve. After path planning, a post-processing method combing with FSW craft is elaborated.

Simulation and real experiment demonstrate that the proposed strategy, which obtains cutter locations of welding and normals without measuring the entire surface, is feasible and effective for the FSW of large thin-walled complex surface parts.

This paper presents a novel method which makes it possible to accurately weld the large thin-wall complex surface part by the FSW robot. The proposed method might be applied to any multi-axes FSW robot similar to the robot studied in this paper.

The purpose of this paper is to design a climbing robot connected by a connecting rod mechanism to achieve multi-functional tasks such as obstacles crossing and climbing of power transmission towers.

A connecting rod type gripper has been designed to achieve stable grasping of angle steel. Before grasping, use coordination between structures to achieve stable docking and grasping. By using the alternating movements of two claws and the middle climbing mechanism, the climbing and obstacle crossing of the angle steel were achieved.

Through a simple linkage mechanism, a climbing robot has been designed, greatly reducing the overall mass of the robot. It can also carry a load of 1 kg, and the climbing mechanism can perform stable climbing. The maximum step distance of the climbing robot is 543 mm, which can achieve the crossing of angle steel obstacles.

A transmission tower climbing mechanism was proposed by analyzing the working environment. Through the locking ability of the screw nut, stable clamping of the angle steel is achieved, and a pitch mechanism is designed to adjust the posture of the hand claw.

An electrochemical method based on the open circuit potential (OCP) fluctuations was put forward. It can be used to optimize the alloy compositions for improving the corrosion resistance of rust layer.

The potential trends and potential fluctuations of carbon steels in seawater were separated by Hodrick–Prescott filter. The Spearman correlation coefficient and max information coefficient were used to explore the correlation of alloy compositions and potential fluctuations.

After long-term immersion, potential fluctuation resistance (PFR) can be used to characterize the corrosion resistance of metals and its rust layers. In the 1,500 to 2,500 h exposure period, Fe, C and S compositions have strong negative correlations, whereas PFR and P composition have weak negative correlations. Mn, Cu and Ti alloy compositions help the rust layer of carbon steels have higher PFRs. These elements that exhibit higher PFRs in this period have been confirmed to have the effect on improving the corrosion resistance of rust layer.

A new computing method for alloy composition optimization of carbon steels based on the OCP fluctuations was put forward. This method combines electrochemical monitoring with the long-term actual seawater environmental tests of various carbon steels.

The aim of this article is two-fold. First, it offers a unique account of San Min, the prototype of the current Chinese educational principle proposed by Yan Fu (1854–1921) that aimed at improving people’s physical, intellectual and moral capacities. This system of educational thinking has received only marginal attention in Anglophone research literature. Second, given the influence of Yan Fu’s interpretation and promulgation of Herbert Spencer’s educational philosophy during that period, it investigates the extent to which San Min is derived from Spencer’s educational thought (the “Spencerian Triad”). This article focusses on how Yan Fu adapted the ideas of San Min from Spencer’s account.

This article considers Yan Fu’s principle of San Min in relation to Spencer’s educational triad through a close reading and comparison of key primary texts (including Yan Fu’s original writing). It explores the similarities and differences between each account of education’s goals and its proposed means of attainment.

Yan Fu’s principle of San Min is shown to have been adapted from the Spencerian Triad. However, using the theory of Social Organism, Yan Fu re-interpreted Spencer’s individual liberty as liberty for the nation. While Spencer’s goal was to empower individuals, Yan Fu aimed to serve collective independence, wealth and power.

This article addresses oversights concerning San Min’s Western origins in the Spencerian Triad and its influence on Chinese education under Yan Fu’s sway. It is significant because San Min is still at the core of the current Chinese educational policy.

There are two opposite views about whether the Antitrust Law is conducive to the development of the economy. One view is that the Antitrust Law can restrain monopoly, maintain market competition and benefit economic growth. The other view is that the Antitrust Law inhibits innovation by monopolistic firms and fosters rent-seeking, which is bad for economic growth. To provide a possible perspective for clarifying the controversy, this paper aims to answer the following two questions: first, will the Antitrust Law inhibit corporate innovation? Second, does the antitrust enforcement agency discriminate against private enterprises?

Based on the samples of A-share listed companies from 2003 to 2013, the authors use the implementation of China’s Antitrust Law in 2008 as a policy shock, take the monopoly enterprises in each industry as the treatment group and competitive enterprises as the control group, using the difference-in-differences method to test the impact of the implementation of the Antitrust Law on corporate innovation activities.

The results show that compared with competitive enterprises, the patent output of monopolistic enterprises was significantly reduced after the implementation of the Antitrust Law, which indicates that the Antitrust Law does inhibit the innovation activities of monopolistic enterprises. Further research finds that the innovation suppression effect of the Antitrust Law is more prominent in state-owned enterprises, which means that the government does not have “selective law enforcement” against private enterprises in the process of law enforcement. Therefore, the results provide evidence for the idea that government intervention is neutral.

First, the paper enriches and expands the research on the factors affecting corporate innovation from the perspective of market structure. Second, it enriches and expands relevant research on the consequences of implementing the Antitrust Law from the perspective of corporate innovation. Third, it not only provides the relevant empirical evidence for clarifying the dispute about the Antitrust Law but also is helpful to clarify whether the Chinese Government has “selective law enforcement” against private enterprises.

Robots are widely used in industrial manufacturing and service industries around the world. However, most of the previous studies on industrial robots use data at the national or industry level in the context of developed countries. This study examines the impact of imported industrial robots on firm innovation at the firm level in China.

Drawing on a large dataset of more than three million records in China, including non-publicly traded small and medium firms, the authors adopt a difference-in-differences method to investigate the impact and channels of industrial robots on firm innovation.

The authors find that the application of industrial robots increases firm innovation. Two possible channels are identified through which robots promote innovation: alleviation of financial constraints and the improvement of human capital. Further analysis shows that the effect of robots on innovation is more pronounced for firms that are highly dependent on external financing, belong to high-tech industries, import high-end robots, have insufficient supply of skilled labor and private firms (non-SOEs). The authors also find that industrial robots increase the firms' innovation quality and the marginal contribution of innovation to firms' total factor productivity.

This study provides big data evidence of the unintended positive consequences of industrial robots on firm innovation. The results are helpful to clarify the controversy of industrial robots. It also has important implications for government industrial policy making, firm innovation and human resource management.

The purpose of this paper is to study how the government stimulates incineration plants to participate in waste classification management, and how to adjust the subsidy strategy for them.

Considering that the classification behavior of residents will produce herd effect, and waste classification can reduce the disposal cost of incineration plants, the authors constructed a differential game model between the government and waste incineration plants, and analyzed the input strategy of the government and incineration plants when they cooperate in the management of municipal waste classification.

Increasing the input level of supervision or raising subsidy price, the government can promote incineration plants to increase the input level of incentive. Moreover, from a long-term perspective, increasing the input level of supervision is more effective. Compared with government supervision, the method of incineration plants incentive can more effectively increase the amount of waste disposal. Furthermore, the government supervision and the incineration plants incentive have a positive interaction effect on improving the amount of waste disposal. Increasing the input level of incineration plants incentive or the level of waste-to-energy technology can increase the amount of waste disposal, and from a long-term perspective, increasing the level of R&D investment is more beneficial to increasing the amount of waste disposal.

The results are helpful to improve the investment in the management of waste classification, and also provide a certain theoretical basis for the government's subsidy policy for incineration plants, so as to reduce the financial pressure of the government.

Why do some employees choose to prolong their working hours excessively? The current study tested how core self-evaluations (CSEs) might lead to workaholism and how perceived job demands might mediate this relationship.

Insights from the extant literature underpin the hypotheses on how CSEs would affect the development of workaholism through perceived job demands. A sample of 421 working people in China completed the online surveys, and the mediation model was tested using Mplus 7.0 (Muthén and Muthén, 1998–2012).

This study found that different components of CSEs influence workaholism in different ways. Specifically, generalized self-efficacy positively predicts workaholism, whereas emotional stability negatively predicts workaholism. Moreover, most aspects of CSEs (generalized self-efficacy, emotional stability and locus of control) influence workaholism via perceived job demands, specifically via perceived workload but not via perceived job insecurity.

The current study is the first to explore how individuals' fundamental evaluations of themselves (i.e. CSEs) relate to workaholism. The results are helpful for the prevention and intervention of workaholism in organizations.

The rapid development and high penetration of digitalization have triggered profound changes in the energy sector. The purpose of this study is to integrate the government digital transformation into the analysis framework and discuss its impact on urban energy efficiency and its realization mechanism.

Using the “Information Benefit Pilot City” (IBC) policy as a quasi-natural experiment, and drawing on data from 285 prefecture-level cities in China from 2008 to 2019, this paper discusses how digital government affects urban energy efficiency by using difference-in-differences (DID).

The results show that digital governance significantly improves energy efficiency, and this conclusion remains reliable even after a series of robustness tests, endogeneity processing and sensitivity analysis. Heterogeneity results show that resource-based, eastern, high economic development level and high urbanization rate city digital government construction are more conducive to improving energy efficiency. The mediating effect shows that the influence mechanism of digital government on energy efficiency mainly includes reducing carbon emission, promoting green technology innovation and attracting talents.

(1) From the perspective of government digital transformation, this study supplements the way to improve energy efficiency and also expands the social dividend of government governance transformation. (2) Through quasi-experimental analysis of IBC policy, this paper solves the problem of difficulty in quantifying the government's digital transformation indicators. (3) The impact heterogeneity and realization mechanism are further discussed and the specific ways of digital government's impact on energy efficiency are revealed.

The purpose of this paper is to propose a knowledge extraction framework to extract knowledge, including entities and relationships between them, from unstructured texts in digital humanities (DH).

The proposed cooperative crowdsourcing framework (CCF) uses both human–computer cooperation and crowdsourcing to achieve high-quality and scalable knowledge extraction. CCF integrates active learning with a novel category-based crowdsourcing mechanism to facilitate domain experts labeling and verifying extracted knowledge.

The case study shows that CCF can effectively and efficiently extract knowledge from multi-sourced heterogeneous data in the field of Tang poetry. Specifically, CCF achieves higher accuracy of knowledge extraction than the state-of-the-art methods, the contribution of feedbacks to the training model can be maximized by the active learning mechanism and the proposed category-based crowdsourcing mechanism can scale up the effective human–computer collaboration by considering the specialization of workers in different categories of tasks.

This research proposes CCF to enable high-quality and scalable knowledge extraction in the field of Tang poetry. CCF can be generalized to other fields of DH by introducing domain knowledge and experts.

The extracted knowledge is machine-understandable and can support the research of Tang poetry and knowledge-driven intelligent applications in DH.

CCF is the first human-in-the-loop knowledge extraction framework that integrates active learning and crowdsourcing mechanisms; he human–computer cooperation method uses the feedback of domain experts through the active learning mechanism; the category-based crowdsourcing mechanism considers the matching of categories of DH data and especially of domain experts.