Yuhua Dong, Chundong Geng, Xiang Wang and Qiong Zhou
This paper aims to investigate effect of porous polystyrene microspheres encapsulated inhibitor on the protection performance of epoxy resin coating.
Abstract
Purpose
This paper aims to investigate effect of porous polystyrene microspheres encapsulated inhibitor on the protection performance of epoxy resin coating.
Design/methodology/approach
Porous polystyrene (PS) microspheres were synthesized by soap-free emulsion polymerization. The morphology of microspheres was observed by scanning electron microscopy and transmission electron microscopy. Corrosion inhibitor benzotriazole was encapsulated into porous PS microspheres. The protection performance of epoxy resin coating with different contents of PS microspheres was tested by polarization curve.
Findings
The findings of electrochemical impedance spectroscopy and scanning vibrating electrode technique showed that addition of corrosion inhibitor to porous PS microspheres further improved the protection performance of the coatings.
Practical implications
Porous PS microspheres could be used as nanocontainer to encapsulate corrosion inhibitor.
Originality/value
Addition of porous PS microspheres with corrosion inhibitor improved the protection performance of the coatings.
Details
Keywords
The purpose of this study is to examine the impact of cross-ownership on corporate digital innovation and their specific mechanisms. Cross-ownership, who hold equity in two or…
Abstract
Purpose
The purpose of this study is to examine the impact of cross-ownership on corporate digital innovation and their specific mechanisms. Cross-ownership, who hold equity in two or more companies simultaneously, have two different types of governance effects in the capital market: governance synergistic effects and competitive collusion effects.
Design/methodology/approach
This paper uses a panel model, selecting A-share company data from 2011 to 2021 in China. In total, 23,853 valid data were obtained, which came from the CSMAR database and Wind database. For some missing data, they were manually supplemented by consulting the company's annual report and Sina Finance. Data processing was conducted using EXCEL and Stata16.0 software.
Findings
The results show that cross-ownership promote corporate digital innovation by leveraging governance synergies. Further grouping tests show that the synergistic effects of cross-ownership are significant in non-state-owned, high-tech, weakly competitive and higher analyst attention enterprises. Mechanism testing shows that cross-ownership can empower corporate digital innovation in three ways: reducing information asymmetry, alleviating financing constraints and improving corporate governance.
Originality/value
The conclusion of this paper provides new empirical evidence for a comprehensive understanding of the role of cross-ownership in corporate development, enriches the economic consequences research of chain institutional investors in China and broadens the research perspective of corporate digital innovation. It also provides important references for the digital transformation of enterprises and the healthy development of the capital market.
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JingRong Li, YuHua Xu, JianLong Ni and QingHui Wang
Hand gesture-based interaction can provide far more intuitive, natural and immersive feelings for users to manipulate 3D objects for virtual assembly (VA). A mechanical assembly…
Abstract
Purpose
Hand gesture-based interaction can provide far more intuitive, natural and immersive feelings for users to manipulate 3D objects for virtual assembly (VA). A mechanical assembly consists of mostly general-purpose machine elements or mechanical parts that can be defined into four types based on their geometric features and functionalities. For different types of machine elements, engineers formulate corresponding grasping gestures based on their domain knowledge or customs for ease of assembly. Therefore, this paper aims to support a virtual hand to assemble mechanical parts.
Design/methodology/approach
It proposes a novel glove-based virtual hand grasping approach for virtual mechanical assembly. The kinematic model of virtual hand is set up first by analyzing the hand structure and possible movements, and then four types of grasping gestures are defined with joint angles of fingers for connectors and three types of parts, respectively. The recognition of virtual hand grasping is developed based on collision detection and gesture matching. Moreover, stable grasping conditions are discussed.
Findings
A prototype system is designed and developed to implement the proposed approach. The case study on VA of a two-stage gear reducer demonstrates the functionality of the system. From the users’ feedback, it is found that more natural and stable hand grasping interaction for VA of mechanical parts can be achieved.
Originality/value
It proposes a novel glove-based virtual hand grasping approach for virtual mechanical assembly.
Details
Keywords
Song Tian, Haitian Long, Yumei Li, Yuhua Sun, Ping Wang and Mingyuan Gao
This study aims to develop a novel self-powered monitoring system that uses radio frequency (RF) energy harvesting and ultra-low-power management technologies for real-time…
Abstract
Purpose
This study aims to develop a novel self-powered monitoring system that uses radio frequency (RF) energy harvesting and ultra-low-power management technologies for real-time condition monitoring of switch rails.
Design/methodology/approach
The system is designed for integration within the jump wire holes of switch rails, ensuring structural integrity and aesthetic appeal. It features a highly efficient energy harvesting mechanism combined with optimized power management for wireless sensor nodes. An on-board antenna captures ambient RF energy, managed by high-efficiency circuits to ensure stable wireless sensor operation. An ultra-low-power system-on-chip is used to acquire and transmit multimodal data on vibration and temperature from the switch rails. The data collection is enhanced through a two-threshold approach, adapting to harvested energy levels for self-energy balancing.
Findings
Testing revealed that the energy harvesting subsystem operated stably at distances up to 2.9 m from the RF source, charging a 200 µF capacitor to 4.2 V in just 220 s. The monitoring subsystem’s average power consumption is in the low microwatt range. Continuous operation over 30 days in real conditions resulted in only a 5 mV reduction in battery voltage, indicating successful self-powered operation and validating long-term reliability in unattended scenarios.
Originality/value
This research presents an innovative solution, integrating RF energy harvesting with ultra-low-power technology, which addresses the power and stability challenges faced by traditional monitoring systems.
Details
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Angga Wahyu Anggoro, Padraig Corcoran, Dennis De Widt and Yuhua Li
International trade transactions, extracted from customs declarations, include several fields, among which the product description and the product category are the most important…
Abstract
Purpose
International trade transactions, extracted from customs declarations, include several fields, among which the product description and the product category are the most important. The product category, also referred to as the Harmonised System Code (HS code), serves as a pivotal component for determining tax rates and administrative purposes. A predictive tool designed for product categories or HS codes becomes an important resource aiding traders in their decision to choose a suitable code. This tool is instrumental in preventing misclassification arising from the ambiguities present in product nomenclature, thus mitigating the challenges associated with code interpretation. Moreover, deploying this tool would streamline the validation process for government officers dealing with extensive transactions, optimising their workload and enhancing tax revenue collection within this domain.
Design/methodology/approach
This study introduces a methodology focused on the generation of sentence embeddings for trade transactions, employing Sentence BERT (SBERT) framework in conjunction with the Multiple Negative Ranking (MNR) Loss function following a contrastive learning paradigm. The procedure involves the construction of pairwise samples, including anchors and positive transactions. The proposed method is evaluated using two publicly available real-world datasets, specifically the India Import 2016 and United States Import 2018 datasets, to fine-tune the SBERT model. Several configurations involving pooling strategies, loss functions, and training parameters are explored within the experimental setup. The acquired representations serve as inputs for traditional machine learning algorithms employed in predicting the product categories within trade transactions.
Findings
Encoding trade transactions utilising SBERT with MNR loss facilitates the creation of enhanced embeddings that exhibit improved representational capacity. These fixed-length embeddings serve as adaptable inputs for training machine learning models, including support vector machine (SVM) and random forest, intended for downstream tasks of HS code classification. Empirical evidence supports the superior performance of our proposed approach compared to fine-tuning transformer-based models in the domain of trade transaction classification.
Originality/value
Our approach generates more representative sentence embeddings by creating the network architectures from scratch with the SBERT framework. Instead of exploiting a data augmentation method generally used in contrastive learning for measuring the similarity between the samples, we arranged positive samples following a supervised paradigm and determined loss through distance learning metrics. This process involves continuous updating of the Siamese or bi-encoder network to produce embeddings derived from commodity transactions. This strategy aims to ensure that similar concepts of transactions within the same class converge closer within the feature embedding space, thereby improving the performance of downstream tasks.
Details
Keywords
Guanchen Liu, Dongdong Xu, Zifu Shen, Hongjie Xu and Liang Ding
As an advanced manufacturing method, additive manufacturing (AM) technology provides new possibilities for efficient production and design of parts. However, with the continuous…
Abstract
Purpose
As an advanced manufacturing method, additive manufacturing (AM) technology provides new possibilities for efficient production and design of parts. However, with the continuous expansion of the application of AM materials, subtractive processing has become one of the necessary steps to improve the accuracy and performance of parts. In this paper, the processing process of AM materials is discussed in depth, and the surface integrity problem caused by it is discussed.
Design/methodology/approach
Firstly, we listed and analyzed the characterization parameters of metal surface integrity and its influence on the performance of parts and then introduced the application of integrated processing of metal adding and subtracting materials and the influence of different processing forms on the surface integrity of parts. The surface of the trial-cut material is detected and analyzed, and the surface of the integrated processing of adding and subtracting materials is compared with that of the pure processing of reducing materials, so that the corresponding conclusions are obtained.
Findings
In this process, we also found some surface integrity problems, such as knife marks, residual stress and thermal effects. These problems may have a potential negative impact on the performance of the final parts. In processing, we can try to use other integrated processing technologies of adding and subtracting materials, try to combine various integrated processing technologies of adding and subtracting materials, or consider exploring more efficient AM technology to improve processing efficiency. We can also consider adopting production process optimization measures to reduce the processing cost of adding and subtracting materials.
Originality/value
With the gradual improvement of the requirements for the surface quality of parts in the production process and the in-depth implementation of sustainable manufacturing, the demand for integrated processing of metal addition and subtraction materials is likely to continue to grow in the future. By deeply understanding and studying the problems of material reduction and surface integrity of AM materials, we can better meet the challenges in the manufacturing process and improve the quality and performance of parts. This research is very important for promoting the development of manufacturing technology and achieving success in practical application.