Bifu Xiong, Siliang He, Jinguo Ge, Quantong Li, Chuan Hu, Haidong Yan and Yu-An Shen
This paper aims to examine the effects of bonding temperature, bonding time, bonding pressure and the presence of a Pt catalyst on the bonding strength of Cu/SB/P-Cu/SB/Cu joints…
Abstract
Purpose
This paper aims to examine the effects of bonding temperature, bonding time, bonding pressure and the presence of a Pt catalyst on the bonding strength of Cu/SB/P-Cu/SB/Cu joints by transient liquid phase bonding (TLPB).
Design/methodology/approach
TLPB is promising to assemble die-attaching packaging for power devices. In this study, porous Cu (P-Cu) foil with a distinctive porous structure and Sn-58Bi solder (SB) serve as the bonding materials for TLPB under a formic acid atmosphere (FA). The high surface area of P-Cu enables efficient diffusion of the liquid phase of SB, stimulating the wetting, spreading and formation of intermetallic compounds (IMCs).
Findings
The higher bonding temperature decreased strength due to the coarsening of IMCs. The longer bonding time reduced the bonding strength owing to the coarsened Bi and thickened IMC. Applying optimal bonding pressure improved bonding strength, whereas excessive pressure caused damage. The presence of a Pt catalyst enhanced bonding efficiency and strength by facilitating reduction–oxidation reactions and oxide film removal.
Originality/value
Overall, this study demonstrates the feasibility of low-temperature TLPB for Cu/SB/P-Cu/SB/Cu joints and provides insights into optimizing bonding strength for the interconnecting materials in the applications of power devices.
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Haidong Yu, Chunzhang Zhao, Bin Zheng and Hao Wang
Thin-walled structures inevitably always have manufacturing deviations, which affects the assembly quality of mechanical products. The assembly quality directly determines the…
Abstract
Purpose
Thin-walled structures inevitably always have manufacturing deviations, which affects the assembly quality of mechanical products. The assembly quality directly determines the performances, reliability and service life of the products. To achieve the automatic assembly of large-scale thin-walled structures, the sizing force of the structures with deviations should be calculated, and its assembling ability should be studied before assembly process. The purpose of this study is to establish a precise model to describe the deviations of structures and to study the variation propagation during assembly process.
Design/methodology/approach
Curved thin-walled structures are modeled by using the shell element via the absolute nodal coordinate formulation. Two typical deviation modes of the structure are defined. The generalized elastic force of shell elements with anisotropic materials is deduced based on a continuum mechanics approach to account for the geometric non-linearity. The quasi-static method is introduced to describe the assembly process. The effects of the deviation forms, geometrical parameters of the thin-walled structures and material properties on assembly quality are investigated numerically.
Findings
The geometric non-linearity of structure and anisotropy of materials strongly affect the variation propagation and the assembly quality. The transformation and accumulation effects of the deviations are apparent in the multiple assembly process. The constraints on the structures during assembly can reduce assembly deviation.
Originality/value
The plate element via the absolute nodal coordinate formulation is first introduced to the variation propagation analysis. Two typical shape deviation modes are defined. The elastic force of structures with anisotropic materials is deduced. The variation propagation during the assembly of structures with various geometrical and material parameters is investigated.
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The purpose of this study is to empirically explore the impact of government subsidies for the digital economy on corporate innovation. It aims to determine whether these…
Abstract
Purpose
The purpose of this study is to empirically explore the impact of government subsidies for the digital economy on corporate innovation. It aims to determine whether these subsidies promote innovation, and to examine the specific ways in which they inspire corporate innovation.
Design/methodology/approach
This study selects Chinese A-share listed companies during the period from 2007 to 2019 as the research object. It employs panel data to empirically examine the impact of government subsidies in the digital economy on corporate innovation.
Findings
The findings reveal that government subsidies for the digital economy effectively promote corporate innovation. They significantly increase the number and share of invention patents and improve the quality of corporate innovation. Moreover, it is noted that the positive impact is largely confined to non-state-owned enterprises, small firms and those in highly competitive markets.
Originality/value
The contribution of this paper lies in focusing on government subsidies in the digital economy, which is distinct from the general government subsidies in a broad sense.
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Jiawei Xu, Baofeng Zhang, Jianjun Lu, Yubing Yu, Haidong Chen and Jie Zhou
The importance of the agri-food supply chain in both food production and distribution has made the issue of its development a critical concern. Based on configuration theory and…
Abstract
Purpose
The importance of the agri-food supply chain in both food production and distribution has made the issue of its development a critical concern. Based on configuration theory and congruence theory, this research investigates the complex impact of supply chain concentration on financial growth in agri-food supply chains.
Design/methodology/approach
The cluster analysis and response surface methodology are employed to analyse the data collected from 207 Chinese agri-food companies from 2010 to 2022.
Findings
The results indicate that different combination patterns of supply chain concentration can lead to different levels of financial growth. We discover that congruent supplier and customer concentration is beneficial for companies’ financial growth. This impact is more pronounced when the company is in the agricultural production stage of agri-food supply chains. Post-hoc analysis indicates that there exists an inverted U-shaped relationship between the overall levels of supply chain concentration and financial growth.
Practical implications
Our research uncovers the complex interplay between supply chain base and financial outcomes, thereby revealing significant ramifications for agri-food supply chain managers to optimise their strategies for exceptional financial growth.
Originality/value
This study proposes a combined approach of cluster analysis and response surface analysis for analysing configuration issues in supply chain management.
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Shanhua Qian, Longfei Gong, Wei Wang, Zifeng Ni and Haidong Ren
This study aims to reduce the harm of industrial lubricants to consumers. Composite aluminum-based grease (CAG) was prepared, and medical-grade montmorillonite (M-MMT) was used to…
Abstract
Purpose
This study aims to reduce the harm of industrial lubricants to consumers. Composite aluminum-based grease (CAG) was prepared, and medical-grade montmorillonite (M-MMT) was used to improve the antiwear performance of the prepared grease.
Design/methodology/approach
The influence of the additive (M-MMT) on the tribological performance is mainly investigated using a ball-disc wear tester, and the wear scar surface about the disc was characterized by white light interferometer and electrochemical workstation. Moreover, the cell viability test was used to evaluate the safety of the grease.
Findings
The results indicated that for the grease containing 1.5% M-MMT, the average coefficient of friction was reduced by about 46% compared with the CAG, the wear volume of the disc reduced by about 74%. Moreover, CAG and 1.5% M-MMT-containing CAG were proved safety by means of the cell viability test.
Originality/value
The integral properties of CAG can be improved with the medical-grade materials as the additives, while ensuring the safety.
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Dan Yuan, Jiejie Du, Yaguang Pan and Chenxi Li
This study explores the role of industrial co-agglomeration and digital economy in influencing the green high-quality development of the Yellow River National Cultural Park to…
Abstract
Purpose
This study explores the role of industrial co-agglomeration and digital economy in influencing the green high-quality development of the Yellow River National Cultural Park to provide countermeasures and suggestions for promoting the whole-area high-quality development.
Design/methodology/approach
This study is based on panel data from 56 cities from 2010 to 2022. First, a Super-SBM model is built to evaluate green high-quality development. Secondly, location entropy is used to measure industrial co-agglomeration and the entropy weight method is used to measure the digital economy. Finally, the panel Tobit model is used to analyze the impact of industrial co-agglomeration and digital economy on the green high-quality development of Yellow River National Cultural Park.
Findings
This study found that (1) industrial co-agglomeration has a negative implication in green high-quality development, while the digital economy boosts green high-quality development; (2) industrial co-agglomeration is a less critical dependency on the level of development of the digital economy in influencing green high-quality development, while the facilitating effect of the digital economy is more dependent on industrial co-agglomeration and (3) the trend of slow growth in industrial co-agglomeration and digital economy development, with significant regional differences in green high-quality development.
Research limitations/implications
Undeniably, our study has several limitations. Firstly, as the study area only includes some cities in individual provinces, such as Qinghai, this paper only analyzes at the city level, which does not better reflect the differences between provinces; secondly, this study only adopts one method to determine the digital economy. In the future, other methods can be explored to measure digital economy; finally, in addition to the main role of digital economy and industrial co-agglomeration, other factors may also affect the green high-quality development of YRNCP. Future research should introduce other variables to improve the theoretical framework.
Practical implications
First, it provides countermeasures and suggestions for promoting the green high-quality development of YRNCP. Second, it helps to implement the new development concept, cultivate the new quality productivity of culture and the tourism industry and promote the green high-quality development of YRNCP. Third, it provides references to improve the management measures and related policies of the YRNCP more accurately and efficiently. Fourth, it helps to build a new development pattern and has important practical significance in promoting the high-quality development of the whole basin, protecting and inheriting the Yellow River Culture and helping the Chinese-style modernization and development, which are of great practical significance.
Social implications
The research is carried out from the new perspective of industrial co-agglomeration and digital economy, which provides the theoretical basis and reference for solving the problem of green high-quality development of YRNCP. Second, it broadens the research idea of green high-quality development. Third, it quantitatively analyzes the impact of industrial co-agglomeration and digital economy on the high-quality development of YRNCP, deepening the research on the green high-quality development of YRNCP. Fourth, it helps to enrich and improve the theoretical research related to the national cultural park development and has positive significance in promoting the management and innovation of the cultural industry and the construction of related disciplines.
Originality/value
The paper’s findings illustrate the functional relationship of the digital economy and industrial co-agglomeration with green high-quality development and propose countermeasures to facilitate the high-quality development of the Yellow River National Cultural Park.
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Since the “open‐door” policy was introduced in 1978, China’s socio‐economic development has been impressive, and the standard of living of its approximately 1.2 billion population…
Abstract
Since the “open‐door” policy was introduced in 1978, China’s socio‐economic development has been impressive, and the standard of living of its approximately 1.2 billion population has generally improved. However, with the rapid economic development and technological advancement comes the inevitable income and social inequality between urban and rural residents as well as among the populace in different regions of China. The disparity in consumption and shopping patterns between higher income and lower income consumers, as well as the recent deflation and “premature consumption psychology” phenomenon in China, have become major challenges for existing shopping centers, and the development of the retail sector as a whole. Based on official data from 1991 to 1998 and empirical evidence from a 1998/9 study, this paper examines the differences in consumption and shopping patterns among consumers in China and discusses the reasons behind such disparity.
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Rashmini Sharma, Shavneet Sharma and Gurmeet Singh
This study aims to explore customers’ second-hand clothing purchases and their engagement on the Facebook marketplace.
Abstract
Purpose
This study aims to explore customers’ second-hand clothing purchases and their engagement on the Facebook marketplace.
Design/methodology/approach
A conceptual model is developed, building upon the online second-hand shopping motivation (OSSM) scale. Data gathered from 409 respondents was analysed using covariance-based structural equation modelling.
Findings
The results highlight that economic, convenience, ideological motivations and environmental concerns impact customers’ purchase intention. Conversely, status consumption was found to impede customers’ purchase intentions. Notably, the elements of social media engagement, including consumption, contribution and creation, demonstrated significance as a consequence of customers’ second-hand clothing purchase intention.
Originality/value
This study’s findings contribute to the knowledge encompassing sustainable fashion consumption, information systems and second-hand social media shopping. It uniquely explores customer behaviours related to second-hand clothes shopping on the Facebook marketplace by building upon the OSSM scale. These findings offer valuable insights, showcasing the determinants that can increase customer-centric social media engagement. These results inform online retailers on Facebook marketplace about sustainable practices, aligning with UN Sustainable Development Goals 12, 13 and 8, to promote a green global economy.
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Abstract
Purpose
This paper aims to develop an optimization model to enhance pipeline assembly performance. It focuses on predicting the pipeline’s assembly pose while ensuring compliance with clamp constraints.
Design/methodology/approach
The assembly pose of the pipeline is quantitatively assessed by a proposed indicator based on joint defects. The assembly interference between the pipeline and assembly boundary is characterized quantitatively. Subsequently, an analytical mapping relationship is established between the assembly pose and assembly interference. A digital fitting model, along with a novel indicator, is established to discern the fit between the pipeline and clamp. Using the proposed indicators as the optimization objective and penalty term, an optimization model is established to predict the assembly pose based on the reinforced particle swarm optimization, incorporating a proposed adaptive inertia weight.
Findings
The optimization model demonstrates robust search capability and rapid convergence, effectively minimizing joint defects while adhering to clamp constraints. This leads to enhanced pipeline assembly efficiency and the achievement of a one-time assembly process.
Originality/value
The offset of the assembly boundary and imperfections in pipeline manufacturing may lead to joint defects during pipeline assembly, as well as failure in the fit between the pipeline and clamp. The assembly pose predicted by the proposed optimization model can effectively reduce the joint defects and satisfy clamp constraints. The efficiency of pipeline modification and assembly has been significantly enhanced.
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Tan Zhang, Zhanying Huang, Ming Lu, Jiawei Gu and Yanxue Wang
Rotating machinery is a crucial component of large equipment, and detecting faults in it accurately is critical for reliable operation. Although fault diagnosis methods based on…
Abstract
Purpose
Rotating machinery is a crucial component of large equipment, and detecting faults in it accurately is critical for reliable operation. Although fault diagnosis methods based on deep learning have been significantly developed, the existing methods model spatial and temporal features separately and then weigh them, resulting in the decoupling of spatiotemporal features.
Design/methodology/approach
The authors propose a spatiotemporal long short-term memory (ST-LSTM) method for fault diagnosis of rotating machinery. The authors collected vibration signals from real rolling bearing and gearing test rigs for verification.
Findings
Through these two experiments, the authors demonstrate that machine learning methods still have advantages on small-scale data sets, but our proposed method exhibits a significant advantage due to the simultaneous modeling of the time domain and space domain. These results indicate the potential of the interactive spatiotemporal modeling method for fault diagnosis of rotating machinery.
Originality/value
The authors propose a ST-LSTM method for fault diagnosis of rotating machinery. The authors collected vibration signals from real rolling bearing and gearing test rigs for verification.