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1 – 10 of 35Chengguo Liu, Junyang Li, Zeyu Li and Xiutao Chen
The study aims to equip robots with the ability to precisely maintain interaction forces, which is crucial for tasks such as polishing in highly dynamic environments with unknown…
Abstract
Purpose
The study aims to equip robots with the ability to precisely maintain interaction forces, which is crucial for tasks such as polishing in highly dynamic environments with unknown and varying stiffness and geometry, including those found in airplane wings or thin, soft materials. The purpose of this study is to develop a novel adaptive force-tracking admittance control scheme aimed at achieving a faster response rate with higher tracking accuracy for robot force control.
Design/methodology/approach
In the proposed method, the traditional admittance model is improved by introducing a pre-proportional-derivative controller to accelerate parameter convergence. Subsequently, the authors design an adaptive law based on fuzzy logic systems (FLS) to compensate for uncertainties in the unknown environment. Stability conditions are established for the proposed method through Lyapunov analysis, which ensures the force tracking accuracy and the stability of the coupled system consisting of the robot and the interaction environment. Furthermore, the effectiveness and robustness of the proposed control algorithm are demonstrated by simulation and experiment.
Findings
A variety of unstructured simulations and experimental scenarios are designed to validate the effectiveness of the proposed algorithm in force control. The outcomes demonstrate that this control strategy excels in providing fast response, precise tracking accuracy and robust performance.
Practical implications
In real-world applications spanning industrial, service and medical fields where accurate force control by robots is essential, the proposed method stands out as both practical and straightforward, delivering consistently satisfactory performance across various scenarios.
Originality/value
This research introduces a novel adaptive force-tracking admittance controller based on FLS and validated through both simulations and experiments. The proposed controller demonstrates exceptional performance in force control within environments characterized by unknown and varying.
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Linghuan Li, Shibin Sun, Ronghua Zhuang, Bing Zhang, Zeyu Li and Jianying Yu
This study aims to develop a polymer cement-based waterproof coating with self-healing capability to efficiently and intelligently solve the building leakage caused by cracking of…
Abstract
Purpose
This study aims to develop a polymer cement-based waterproof coating with self-healing capability to efficiently and intelligently solve the building leakage caused by cracking of waterproof materials, along with excellent durability to prolong its service life.
Design/methodology/approach
Ion chelators are introduced into the composite system based on ethylene vinyl acetate copolymer emulsion and ordinary Portland cement to prepare self-healing polymer cement-based waterproof coating. Hydration, microstructure, wettability, mechanical properties, durability, self-healing performance and self-healing products of polymer cement-based waterproof coating with ion chelator are investigated systematically. Meanwhile, the chemical composition of self-healing products in the crack was examined.
Findings
The results showed that ion chelators could motivate the hydration of C2S and C3S, as well as the formation of hydration products (C-S-H gel) of the waterproof coating to improve its compactness. Compared with the control group, the waterproof coating with ion chelator had more excellent water resistance, alkali resistance, thermal and UV aging resistance. When the dosage of ion chelator was 2%, after 28 days of curing, cracks with a width of 0.29 mm in waterproof coating could fully heal and cracks with a width of 0.50 mm could achieve a self-healing efficiency of 72%. Furthermore, the results reveal that the self-healing product in the crack was calcite crystalline CaCO3.
Originality/value
A novel ion chelator was introduced into the composite coating system to endow it with excellent self-healing ability to prolong its service life. It has huge application potential in the field of building waterproofing.
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Zeyu Li, Weidong Liu, Le Li, Zhi Liu and Feihu Zhang
Underwater shuttle is widely used in scenarios of deep sea transportation and observation. As messages are transmitted via the limited network, high transmission time-delay often…
Abstract
Purpose
Underwater shuttle is widely used in scenarios of deep sea transportation and observation. As messages are transmitted via the limited network, high transmission time-delay often leads to information congestion, worse control performance and even system crash. Moreover, due to the nonlinear issues with respect to shuttle’s heading motion, the delayed transmission also brings extra challenges. Hence, this paper aims to propose a co-designed method, for the purpose of network scheduling and motion controlling.
Design/methodology/approach
First, the message transmission scheduling is modeled as an optimization problem via adaptive genetic algorithm. The initial transmission time and the genetic operators are jointly encoded and adjusted to balance the payload in network. Then, the heading dynamic model is compensated for the delayed transmission, in which the parameters are unknown. Therefore, the adaptive sliding mode controller is designed to online estimate the parameters, for enhancing control precision and anti-interference ability. Finally, the method is evaluated by simulation.
Findings
The messages in network are well scheduled and the time delay is thus reduced, which increases the quality of service in network. The unknown parameters are estimated online, and the quality of control is enhanced. The control performance of the shuttle control system is thus increased.
Originality/value
The paper is the first to apply co-design method of message scheduling and attitude controlling for the underwater unmanned vehicle, which enhaces the control performance of the network control system.
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Wan Liu, Zeyu Li, Li Chen, Dexin Zhang and Xiaowei Shao
This paper aims to innovatively propose to improve the efficiency of satellite observation and avoid the waste of satellite resources, a genetic algorithm with entropy operator…
Abstract
Purpose
This paper aims to innovatively propose to improve the efficiency of satellite observation and avoid the waste of satellite resources, a genetic algorithm with entropy operator (GAE) of synthetic aperture radar (SAR) satellites’ task planning algorithm.
Design/methodology/approach
The GAE abbreviated as GAE introduces the entropy value of each orbit task into the fitness calculation of the genetic algorithm, which makes the orbit with higher entropy value more likely to be selected and participate in the remaining process of the genetic algorithm.
Findings
The simulation result shows that in a condition of the same calculate ability, 85% of the orbital revisit time is unchanged or decreased and 30% is significantly reduced by using the GAE compared with traditional task planning genetic algorithm, which indicates that the GAE can improve the efficiency of satellites’ task planning.
Originality/value
The GAE is an optimization of the traditional genetic algorithm. It combines entropy in thermodynamics with task planning problems. The algorithm considers the whole lifecycle of task planning and gets the desired results. It can greatly improve the efficiency of task planning in observation satellites and shorten the entire task execution time. Then, using the GAE to complete SAR satellites’ task planning is of great significance in reducing satellite operating costs and emergency rescue, which brings certain economic and social benefits.
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Zeyu Li, Mazlina Mustapha, Ahmad Fahmi Sheikh Hassan and Saidatunur Fauzi Saidin
This study examines the impact of corporate governance on succession planning and organizational performance. Drawing on agency theory, the main purpose of this study is to…
Abstract
Purpose
This study examines the impact of corporate governance on succession planning and organizational performance. Drawing on agency theory, the main purpose of this study is to identify the effect of corporate governance on succession planning by measuring the different characteristics of the board of directors.
Design/methodology/approach
This multi-quantitative research used primary and archival data. A total of 281 valid questionnaires were collected from Chinese listed family firms to gauge succession planning. Relevant archival data were obtained to measure board characteristics and organizational performance. All hypotheses were examined through structural equation modeling.
Findings
The outcomes indicate that corporate governance positively influences succession planning and, in turn, boosts superior organizational performance, which uncovers the mediating effect of succession planning on the relationship between corporate governance and organizational performance. Our findings reveal that board independence and education facilitate the development of succession planning, which is crucial in the family business’s life cycle.
Originality/value
The results of this study contribute to management succession, strategic management and leadership research by demonstrating how corporate governance fosters organizational performance through succession planning, thereby expanding the application scenarios of agency theory in family firms. Additionally, the article also enriches our understanding of how family businesses apply sound governance structures to promote organizational strategic decision-making during the succession process.
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Zhili Zhao, Mingqiang Zhang, Xi Meng, Zhenkun Li, Jiazhe Li, Luying Qiu and Zeyu Ren
The author proposed a friction plunge micro-welding (FPMW) method and applied it to column grid array packaging to realize the connection of copper columns without precision molds…
Abstract
Purpose
The author proposed a friction plunge micro-welding (FPMW) method and applied it to column grid array packaging to realize the connection of copper columns without precision molds assisted positioning. The purpose of this paper is to study the flow behavior of the solder undergoing frictional thermo-mechanical action during the FPMW and to determine the source of the solders in the micro-zones with different microstructure characteristics near the solder/Cu column friction interface.
Design/methodology/approach
Three kinds of Sn58Bi/SAC305 and SAC305/Pb90Sn composite solder samples were designed to study the flow behavior of the solder during FPMW using Bi and Pb as tracer elements.
Findings
The results show that most of the solders in the position occupied by the copper column was softened and plasticized during the welding process and was extruded to side of the copper column, flowing axially, circumferentially and radially along a trajectory similar to a conical spiral line. Under the drive of the tangential friction force and the radial hold-tight force, the extruded out visco-plastic solders fully mixed with the visco-plastic solders on the sides of the copper column, and bonded with the solders that deformed plastically on the periphery, so that a stir zone and a dynamic recrystallization zone finally evolved. The outside plastically deformed solders evolved into a thermo-mechanical affected zone.
Originality/value
The flow behavior of the solder during the FPMW was determined, as well as the source of the solders in micro-zones with different microstructure characteristics.
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Xu Li, Zeyu Xiao, Zhenguo Zhao, Junfeng Sun and Shiyuan Liu
To explore the economical and reasonable semi-rigid permeable base layer ratio, solve the problems caused by rainwater washing over the pavement base layer on the slope, improve…
Abstract
Purpose
To explore the economical and reasonable semi-rigid permeable base layer ratio, solve the problems caused by rainwater washing over the pavement base layer on the slope, improve its drainage function, improve the water stability and service life of the roadbed pavement and promote the application of semi-rigid permeable base layer materials in the construction of asphalt pavement in cold regions.
Design/methodology/approach
In this study, three semi-rigid base course materials were designed, the mechanical strength and drainage properties were tested and the effect and correlation of air voids on their performance indexes were analyzed.
Findings
It was found that increasing the cement content increased the strength but reduced the air voids and water permeability coefficient. The permeability performance of the sandless material was superior to the dense; the performance of the two sandless materials was basically the same when the cement content was 7%. Overall, the skeleton void (sand-containing) type gradation between the sandless and dense types is more suitable as permeable semi-rigid base material; its gradation is relatively continuous, with cement content? 4.5%, strength? 1.5 MPa, water permeability coefficient? 0.8 cm/s and voids of 18–20%.
Originality/value
The study of permeable semi-rigid base material with large air voids could help to solve the problems of water damage and freeze-thaw damage of the base layer of asphalt pavements in cold regions and ensure the comfort and durability of asphalt pavements while having good economic and social benefits.
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Abstract
Purpose
Labor conflict has become a serious problem in recent China. From the perspective of entrepreneur innovation, this paper aims to find an effective path to eliminate this conflict. On the basis of theoretical analyses and regression analyses, this paper finds that, with legal environment and other conditions identical, entrepreneur innovation will significantly facilitate elimination of labor conflicts.
Design/methodology/approach
Using theoretical analyses based on entrepreneurship theory, this paper puts forward a series of hypotheses about the effects of entrepreneur innovation on labor conflicts. With panel data during 2013-2015 from China Employer–Employee Survey, this paper examines the effects of entrepreneur innovation on labor conflicts. Using interaction term regressions, this paper examines heterogeneous effects of entrepreneur innovation on labor conflicts by ownership, market power and export behavior. With mediating effect model, this paper examine whether workers’ participation in corporation governance is an important channel in which entrepreneurial innovation can impact on labor conflicts.
Findings
First, using benchmark regressions and robustness checks, this paper finds that there exist significantly positive effects of entrepreneur innovation on workers’ job satisfaction, incentive, social security, job development and job stability, which will reduce potential risks of labor conflict effectively. Second, using interaction term regressions, this paper finds that there exist heterogeneous effects of entrepreneur innovation on labor conflicts by ownership, market power and export behaviors. The study finds that the effects of entrepreneur innovation are more concentrated in private firms, firms with stronger market power and non-exporters. Third, using a mediating effect model, the study finds that workers’ participation in corporation governance is an important channel in which entrepreneur innovation can have impacts on labor conflicts.
Originality/value
The paper enriches the existing research about how to eliminate labor conflicts in China. On the basis of China Employer–Employee Survey data, this paper finds the importance of entrepreneur innovation on Chinese transition, which not only has positive impacts on firm performance, but also has impacts on eliminating labor conflicts and establishing better labor relationship. Therefore, stimulating entrepreneur innovation is very important for solving conflicts during Chinese transition.
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Abstract
Purpose
This paper aims to forecast the future development of UIC technology according to the changes of IPC in different time periods. The findings also provide a theoretical basis for the UIC policymakers of energy-saving environmental protection industry.
Design/methodology/approach
The present study will take energy-saving technology as an example, through using a two-mode network analysis method to build the four-stage IPC code UIC innovation-technology network, researching UIC innovation network applicant heterogeneity, UIC technology network and technology relevance.
Findings
Through the establishment of UIC innovation-technology two-mode network, namely, applicant node CN and IPC node TN, this paper analyzes the important applicants, focal technologies, correlation of focal technologies and the development trends of energy saving technology in the future by using the related theories and methods of two-mode network.
Originality/value
At present, only about 11% of energy-saving enterprises in China have R&D activities. The government needs to implement top-level design, improve industrial policies, strengthen investment in technology R&D and build a platform for technological innovation in energy-saving industries to support the R&D of common and key technologies in energy-saving industries.
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Bing Xue, Rui Yao, Zengyu Ye, Cheuk Ting Chan, Dickson K.W. Chiu and Zeyu Zhong
With the rapid development of social media, many organizations have begun to attach importance to social media platforms. This research studies the management and the use of…
Abstract
Purpose
With the rapid development of social media, many organizations have begun to attach importance to social media platforms. This research studies the management and the use of social media in academic music libraries, taking the Center for Chinese Music Studies of the Chinese University of Hong Kong (CCMS) as a case study.
Design/methodology/approach
We conducted a sentiment analysis of posts on Facebook’s public page to analyze the reaction to the posts with some exploratory analysis, including the communication trend and relevant factors that affect user interaction.
Findings
Our results show that the Facebook channel for the library has a good publicity effect and active interaction, but the number of posts and interactions has a downward trend. Therefore, the library needs to pay more attention to the management of the Facebook channel and take adequate measures to improve the quality of posts to increase interaction.
Originality/value
Few studies have analyzed existing data directly collected from social media by programming based on sentiment analysis and natural language processing technology to explore potential methods to promote music libraries, especially in East Asia, and about traditional music.
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