Lei Dong, Xiaoyu Zhang, Kun Liu, Xiaojun Liu, Ruiming Shi, Junyuan Wang and Feng Liu
The purpose of this paper is to investigate the tribological properties of the WC/TiC-Co substrate under different loading conditions under three impact abrasive wear conditions.
Abstract
Purpose
The purpose of this paper is to investigate the tribological properties of the WC/TiC-Co substrate under different loading conditions under three impact abrasive wear conditions.
Design/methodology/approach
The three body collisional wear behavior of Co alloy with WC and TiC at three impact energy was studied from 1 to 3 J. Meanwhile, the microstructure, hardness, phase transformation and wear behavior of these specimens were investigated by scanning electron microscopy, Rockwell hardness (HRV), EDS and impact wear tester. The resulting wear rate was quantified by electronic balance measurements under different pressures.
Findings
The specific wear rate increases with the increase of the nonlinearity of the impact energy and the increase in the content of WC or TiC. The effect of TiC on wear rate is greater than that of WC, but the hardness is smaller. The wear characteristics of the samples are mainly characterized by three kinds of behavior, such as cutting wear, abrasive wear and strain fatigue wear. The WC-Co with fewer TiC samples suffered heavier abrasive wear than the more TiC samples under both low and high impact energy and underwent fewer strain fatigue wears under high impact energy.
Originality/value
The experimental results show that the wear resistance of the Co alloy is improved effectively and the excellent impact wear performance is achieved. The results can be used in cutting tools such as coal mine cutting machines or other fields.
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Shuai Yang, Bin Wang, Junyuan Tao, Zhe Ruan and Hong Liu
The 6D pose estimation is a crucial branch of robot vision. However, the authors find that due to the failure to make full use of the complementarity of the appearance and…
Abstract
Purpose
The 6D pose estimation is a crucial branch of robot vision. However, the authors find that due to the failure to make full use of the complementarity of the appearance and geometry information of the object, the failure to deeply explore the contributions of the features from different regions to the pose estimation, and the failure to take advantage of the invariance of the geometric structure of keypoints, the performances of the most existing methods are not satisfactory. This paper aims to design a high-precision 6D pose estimation method based on above insights.
Design/methodology/approach
First, a multi-scale cross-attention-based feature fusion module (MCFF) is designed to aggregate the appearance and geometry information by exploring the correlations between appearance features and geometry features in the various regions. Second, the authors build a multi-query regional-attention-based feature differentiation module (MRFD) to learn the contribution of each region to each keypoint. Finally, a geometric enhancement mechanism (GEM) is designed to use structure information to predict keypoints and optimize both pose and keypoints in the inference phase.
Findings
Experiments on several benchmarks and real robot show that the proposed method performs better than existing methods. Ablation studies illustrate the effectiveness of each module of the authors’ method.
Originality/value
A high-precision 6D pose estimation method is proposed by studying the relationship between the appearance and geometry from different object parts and the geometric invariance of the keypoints, which is of great significance for various robot applications.
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This study seeks to understand how accountant stereotypes have been constructed and reconstructed at the macro-national and the structural level in Chinese society.
Abstract
Purpose
This study seeks to understand how accountant stereotypes have been constructed and reconstructed at the macro-national and the structural level in Chinese society.
Design/methodology/approach
This qualitative investigation into China's social construction of accountant stereotypes employs Becker's (1963) labelling theory. Viewing stereotyping as a socially constructed practice, this study draws on a post-positivistic, reflexive epistemology in conducting 28 semi-structured interviews with accountants and related actors.
Findings
Chinese accountant stereotypes are constructed and reconstructed according to the rules created and enforced in different cultural-political periods. The accountant stereotypes constructed during the ancient Confucian period (500 BC – 1948) were replaced during 1949 and 2012 when the political focus shifted towards propagating socialism and later promoting economic growth. They also show how Confucian stereotypes of accountants resurfaced in 2013 but were reconstructed by the central government's cultural confidence policy of propagating Confucianism.
Originality/value
Empirically, prior literature has focused on what the accountant stereotype is and how accountants respond to such stereotypes, but it has neglected the ways in which these accountant stereotypes are politically and culturally constructed, diffused and legitimated. This paper fills in the gap by understanding the social practice of accountant stereotyping in a previously unexplored political-cultural context, namely Chinese society. In theoretical terms, by offering the first use of Becker's (1963) labelling theory in the accounting literature, it furthermore enhances our understanding of how accountants' identities and social standing are shaped by social rules.
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Zhifeng Liu, Junyuan Guo, Yumo Wang, Dong Xiangmin, Yue Wu, Zhijie Yan and Gong Jinlong
This paper aims to propose a method for finding the maximum rotational speed of an inclined turntable at which the stability of the bearing oil film is maintained.
Abstract
Purpose
This paper aims to propose a method for finding the maximum rotational speed of an inclined turntable at which the stability of the bearing oil film is maintained.
Design/methodology/approach
The finite difference method was used to solve the Reynolds equation. Variation of bearing capacity of a tilted hydrostatic turret over time was determined. The combined effect of tilt and rotational speed of the turret on the oil film stability was also analyzed.
Findings
When the turntable is operated at low speeds with only small angle of tilt, stability of the oil film is maintained. At lower rotational speeds, a smaller angle of tilt improves the bearing capacity and ensures stability of the oil film. Whereas, higher rotational speeds can have a considerable influence on the bearing capacity.
Originality/value
The results demonstrate that the inclination or tilt of the turntable significantly affects the stability of the oil film.
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Jun Liu, Junyuan Dong, Mingming Hu and Xu Lu
Existing Simultaneous Localization and Mapping (SLAM) algorithms have been relatively well developed. However, when in complex dynamic environments, the movement of the dynamic…
Abstract
Purpose
Existing Simultaneous Localization and Mapping (SLAM) algorithms have been relatively well developed. However, when in complex dynamic environments, the movement of the dynamic points on the dynamic objects in the image in the mapping can have an impact on the observation of the system, and thus there will be biases and errors in the position estimation and the creation of map points. The aim of this paper is to achieve more accurate accuracy in SLAM algorithms compared to traditional methods through semantic approaches.
Design/methodology/approach
In this paper, the semantic segmentation of dynamic objects is realized based on U-Net semantic segmentation network, followed by motion consistency detection through motion detection method to determine whether the segmented objects are moving in the current scene or not, and combined with the motion compensation method to eliminate dynamic points and compensate for the current local image, so as to make the system robust.
Findings
Experiments comparing the effect of detecting dynamic points and removing outliers are conducted on a dynamic data set of Technische Universität München, and the results show that the absolute trajectory accuracy of this paper's method is significantly improved compared with ORB-SLAM3 and DS-SLAM.
Originality/value
In this paper, in the semantic segmentation network part, the segmentation mask is combined with the method of dynamic point detection, elimination and compensation, which reduces the influence of dynamic objects, thus effectively improving the accuracy of localization in dynamic environments.
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Lei Hu, Yun Wang, Jie Zhang, Jun Zhang, Yan Cui, Lvzhong Ma, Junyuan Jiang, Liming Fang and Bangcheng Zhang
As Chinese massage is increasingly popular, many physicians are needed these days. In order to promote the experience and skills of experts and reduce labour intensity during…
Abstract
Purpose
As Chinese massage is increasingly popular, many physicians are needed these days. In order to promote the experience and skills of experts and reduce labour intensity during massage, a massage robot, which could reproduce the expert techniques with individualized manipulation parameters and enhanced safety control strategies, is presented in this paper.
Design/methodology/approach
The kinematic and force features of key massage techniques, such as Thumb Kneading, Pressing, Rolling, Vibrating and Pinching, are summarized by analyzing the massage processes of expert physicians, and a mathematical model for robotic massage is established. With safety issues taken into account, the overall system structure of the massage robot is proposed. The system generally consists of a positioning platform and a massage end‐effector which implements the massage techniques, and the end‐effector is further divided into a parallel mechanism and a massage hand to accommodate different techniques. Visual tracking is used for positioning acupuncture points by recognizing markers on a massage vest worn by the patient. A pain threshold value is introduced to individualize therapy schemes and a force‐position control method based on the pain threshold is presented.
Findings
VAS (Visual Analogue Scale) tests for lumbar muscle strain are carried out using the massage robot, and the treatment effect of the massage robot based on traditional Chinese massage therapy theory is initially validated.
Research limitations/implications
The treatment effect of the massage robot needs to be assessed clinically for more occasions and more clinical experiments will be conducted, to optimize the configuration and control strategy to meet the clinical needs in future work.
Originality/value
The robotic massage system presented in this paper is acting on acupuncture points based on traditional Chinese massage therapy theory, with human manipulation techniques reproduced and expert experiences incorporated. The massage robot can take the place of a massager to perform Chinese massage. Most of the massage robotic systems published in the world perform only one massage technique and the whole massage process is not completely considered. By comparison, the authors' massage robot could perform five techniques. Furthermore, the authors have designed the procedure of robotic massage specifically for patients who suffer from lumbar muscle strain.
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Despite an intensified anti-corruption campaign, China's economic growth and social transition continue to breed loopholes and opportunities for big corruption, leading to a…
Abstract
Despite an intensified anti-corruption campaign, China's economic growth and social transition continue to breed loopholes and opportunities for big corruption, leading to a money-oriented mentality and the collapse of ethical standards, and exposing the communist regime to greater risk of losing moral credibility and political trust. In Hong Kong, the setting up of the Independent Commission Against Corruption (ICAC) in 1974 marked the advent of a new comprehensive strategy to eradicate corruption and to rebuild trust in government. The ICAC was not just an anti-corruption enforcement agency per se, but an institution spearheading and representing integrity and governance transformation. This chapter considers how mainland China can learn from Hong Kong's experience and use the fight against corruption as a major political strategy to win the hearts and minds of the population and reform governance in the absence of more fundamental constitutional reforms, in a situation similar to Hong Kong's colonial administration of the 1970s–1980s deploying administrative means to minimize a political crisis.