Hui Zhang, Huanhuan Xiong, Qian Wang and Yongjie Gu
This paper aims to explore the impact of enterprise niche on dual innovation performance and the moderating role of innovation openness on the relationship between enterprise…
Abstract
Purpose
This paper aims to explore the impact of enterprise niche on dual innovation performance and the moderating role of innovation openness on the relationship between enterprise niche and dual innovation performance.
Design/methodology/approach
This study uses the panel data of the enterprise technology patents of China's Top 100 Electronic Information Enterprises from 2009 to 2018. Multiple regression analyses were used to test the hypotheses.
Findings
Niche width has a significant positive impact on exploitative and exploratory innovation performance. Niche overlap has an inverted U-shaped effect on exploitative innovation performance and significantly positively affects exploratory innovation performance. Innovation openness negatively moderates the impact of niche width on exploitative innovation performance and positively moderates the impact of niche overlap on exploitative innovation performance.
Originality/value
This study provides new insights into the effects of enterprise niche on dual innovation performance by showing the moderating role of innovation openness. The study finds a strategic logic of moderate niche overlap, clarifies the innovative effect of different innovation openness modes and reveals the construction and management mechanisms of enterprise niche and innovation openness strategy.
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Hai Tan, Yanbao Guo, Junqiang Wang, Deguo Wang and Yongjie Cui
The purpose of this study is to investigate the influence of additive particle size on the anti-corrosion behaviors of polyurethane (PU) coating.
Abstract
Purpose
The purpose of this study is to investigate the influence of additive particle size on the anti-corrosion behaviors of polyurethane (PU) coating.
Design/methodology/approach
The graphite (Gr) and poly-graphite (PGr) were used as large size additive and small size additive, respectively. The immersion test and electrochemical test were used to study the corrosion behaviors.
Findings
In the immersion test, the surface of the bare steel sample was corroded uniformly. However, for the steel samples with coatings, the surfaces were corroded locally. This phenomenon showed that the coating can isolate artificial sea-water and samples and then decreased the corrosion rate. Furthermore, the most severe corrosion was observed on the sample with the Gr/PU coating compared with other anti-corrosion coatings. The results of the electrochemical measurements indicated that the corrosion rate of the sample with PGr/PU coating was approximately two times lower than that of the sample with the Gr/PU coating and the sample with PGr/PU coating was hardest to be corroded.
Originality/value
To have a more objective and direct recognition of the particle size effect on the coating quality.
Xiaojian Jiang, Zhonggui Zhang, Jiafei Cheng, Yongjie Ai, Ziyue Zhang, Shuolei Wang, Shi Xu, Hongyu Gao and Yubing Dong
This study aims to fabricate the reduced graphene oxide (rGO)/ethylene vinyl acetate copolymer (EVA) composite films with electric-driven two-way shape memory properties for…
Abstract
Purpose
This study aims to fabricate the reduced graphene oxide (rGO)/ethylene vinyl acetate copolymer (EVA) composite films with electric-driven two-way shape memory properties for deployable structures application. The effect of dicumyl peroxide (DCP) and rGO on the structure and properties of the rGO/EVA composite films were systematically investigated.
Design/methodology/approach
The rGO/EVA composite films were fabricated by melting blend and swelling-ultrasonication method, DCP and rGO were used the crosslinking agent and conductive filler, respectively.
Findings
The research results indicate that the two-way shape memory properties of rGO/EVA composite films were significantly improved with the increase of DCP content. The rGO endowed rGO/EVA composite films with excellent electric-driven reversible two-way shape memory and anti-ultraviolet aging properties. The sample rGO/EVA-9 can be heated above Tm within 8 s at a voltage of 35 V and can be heated above the Tm temperature within 12 s under near-infrared light (NIR). Under a constant stress of 0.07 MPa, the reversible strain of the sample rGO/EVA-9 was 8.96% and its electric-driven shape memory behavior maintained great regularity and stability.
Research limitations/implications
The rGO/EVA composite films have potential application value in the field of deployable structures.
Originality/value
With the increase of DCP content, the two-way shape memory properties of rGO/EVA composite films were significantly improved, which effectively solved the problem that the shape memory properties of EVA matrix decreased caused by swelling. The rGO endowed rGO/EVA composite films with excellent electric/NIR driven reversible two-way shape memory properties.
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Fukang Yang, Wenjun Wang, Yongjie Yan and YuBing Dong
Polyethylene terephthalate (PET) as a fiber molding polymer is widely used in aerospace, electrical and electronic, clothing and other fields. The purpose of this study is to…
Abstract
Purpose
Polyethylene terephthalate (PET) as a fiber molding polymer is widely used in aerospace, electrical and electronic, clothing and other fields. The purpose of this study is to improve the thermal insulation performance of polyethylene terephthalate (PET), the SiO2 aerogel/PET composites slices and fibers were prepared, and the effects of the SiO2 aerogel on the morphology, structure, crystallization property and thermal conductivity of the SiO2 aerogel/PET composites slices and their fibers were systematically investigated.
Design/methodology/approach
The mass ratio of purified terephthalic acid and ethylene glycol was selected as 1:1.5, which was premixed with Sb2O3 and the corresponding mass of SiO2 aerogel, and SiO2 aerogel/PET composites were prepared by direct esterification and in-situ polymerization. The SiO2 aerogel/PET composite fibers were prepared by melt-spinning method.
Findings
The results showed that the SiO2 aerogel was uniformly dispersed in the PET matrix. The thermal insulation coefficient of PET was significantly reduced by the addition of SiO2 aerogel, and the thermal conductivity of the 1.0 Wt.% SiO2 aerogel/PET composites was reduced by 75.74 mW/(m · K) compared to the pure PET. The thermal conductivity of the 0.8 Wt.% SiO2 aerogel/PET composite fiber was reduced by 46.06% compared to the pure PET fiber. The crystallinity and flame-retardant coefficient of the SiO2 aerogel/PET composite fibers showed an increasing trend with the addition of SiO2 aerogel.
Research limitations/implications
The SiO2 aerogel/PET composite slices and their fibers have good thermal insulation properties and exhibit good potential for application in the field of thermal insulation, such as warm clothes. In today’s society where the energy crisis is becoming increasingly serious, improving the thermal insulation performance of PET to reduce energy loss will be of great significance to alleviate the energy crisis.
Originality/value
In this study, SiO2 aerogel/PET composite slices and their fibers were prepared by an in situ polymerization process, which solved the problem of difficult dispersion of nanoparticles in the matrix and the thermal conductivity of PET significantly reduced.
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Z.F. Zhang, Wei Liu, Egon Ostrosi, Yongjie Tian and Jianping Yi
During the production process of steel strip, some defects may appear on the surface, that is, traditional manual inspection could not meet the requirements of low-cost and…
Abstract
Purpose
During the production process of steel strip, some defects may appear on the surface, that is, traditional manual inspection could not meet the requirements of low-cost and high-efficiency production. The purpose of this paper is to propose a method of feature selection based on filter methods combined with hidden Bayesian classifier for improving the efficiency of defect recognition and reduce the complexity of calculation. The method can select the optimal hybrid model for realizing the accurate classification of steel strip surface defects.
Design/methodology/approach
A large image feature set was initially obtained based on the discrete wavelet transform feature extraction method. Three feature selection methods (including correlation-based feature selection, consistency subset evaluator [CSE] and information gain) were then used to optimize the feature space. Parameters for the feature selection methods were based on the classification accuracy results of hidden Naive Bayes (HNB) algorithm. The selected feature subset was then applied to the traditional NB classifier and leading extended NB classifiers.
Findings
The experimental results demonstrated that the HNB model combined with feature selection approaches has better classification performance than other models of defect recognition. Among the results of this study, the proposed hybrid model of CSE + HNB is the most robust and effective and of highest classification accuracy in identifying the optimal subset of the surface defect database.
Originality/value
The main contribution of this paper is the development of a hybrid model combining feature selection and multi-class classification algorithms for steel strip surface inspection. The proposed hybrid model is primarily robust and effective for steel strip surface inspection.
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Bin Li, Jianzhong Fu, Yongjie Jessica Zhang, Weiyi Lin, Jiawei Feng and Ce Shang
Majority of the existing direct slicing methods have generated precise slicing contours from different surface representations, they do not carry any interior information…
Abstract
Purpose
Majority of the existing direct slicing methods have generated precise slicing contours from different surface representations, they do not carry any interior information. Whereas, heterogeneous solids are highly preferable for designing and manufacturing sophisticated models. To directly slice heterogeneous solids for additive manufacturing (AM), this study aims to present an algorithm using octree-based subdivision and trivariate T-splines.
Design/methodology/approach
This paper presents a direct slicing algorithm for heterogeneous solids using T-splines, which can be applied to AM based on the fused deposition modeling (FDM) technology. First, trivariate T-splines are constructed using a harmonic field with the gradient direction aligning with the slicing direction. An octree-based subdivision algorithm is then used to directly generate the sliced layers with heterogeneous materials. For FDM-based AM applications, the heterogeneous materials of each sliced layer are discretized into a finite number of partitions. Finally, boundary contours of each separated partition are extracted and paired according to the rules of CuraEngine to generate the scan path for FDM machines equipped with multi-nozzles.
Findings
The experimental results demonstrate that the proposed algorithm is effective and reliable, especially for solid objects with multiple materials, which could maintain the model integrity throughout the process from the original representation to the final product in AM.
Originality/value
Directly slicing heterogeneous solid using trivariate T-splines will be a powerful supplement to current technologies in AM.
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This study aimed to analyse user experiences and perceptions of eRupee banking applications in India, focussing on understanding the key factors driving user satisfaction and…
Abstract
Purpose
This study aimed to analyse user experiences and perceptions of eRupee banking applications in India, focussing on understanding the key factors driving user satisfaction and dissatisfaction.
Design/methodology/approach
A comprehensive text-mining approach was employed to analyse 5,176 user reviews collected from the Google Play Store. Sentiment analysis and latent Dirichlet allocation (LDA) were used to classify reviews and uncover prevailing themes.
Findings
The analysis revealed that positive reviews highlighted the themes of usefulness, convenience, satisfaction, app attributes, and ease of use. Negative reviews emphasise issues related to lack of trust, faulty updates, unreliability, security concerns, and inadequate customer support. The Logistic Regression model demonstrated superior performance in predicting user sentiments, achieving an AUC of 0.7926 and an accuracy rate of 77.90%.
Research limitations/implications
This study was limited to reviews from a single-platform source. Future research could incorporate data from multiple online sources and employ qualitative methods to gain deeper insight. Additionally, longitudinal studies and cross-cultural analyses are recommended to capture evolving user sentiments and global perspectives.
Practical implications
The findings provide actionable insights for bank managers, app developers and policymakers to enhance eRupee applications by addressing identified issues and leveraging positive aspects to improve overall user experience and satisfaction.
Originality/value
This study makes a novel contribution to the literature on digital currency and advanced text-mining techniques using machine-learning models to analyse user feedback in the context of an emerging economy. The proposed conceptual model and practical recommendations serve as the foundation for future research and practical development in digital financial services.