Xiaotong Jiang, Xiaosheng Cheng, Qingjin Peng, Luming Liang, Ning Dai, Mingqiang Wei and Cheng Cheng
It is a challenge to print a model with the size that is larger than the working volume of a three-dimensional (3D) printer. The purpose of this paper is to present a feasible…
Abstract
Purpose
It is a challenge to print a model with the size that is larger than the working volume of a three-dimensional (3D) printer. The purpose of this paper is to present a feasible approach to divide a large model into small printing parts to fit the volume of a printer and then assemble these parts into the final model.
Design/methodology/approach
The proposed approach is based on the skeletonization and the minima rule. The skeleton of a printing model is first extracted using the mesh contraction and the principal component analysis. The 3D model is then partitioned preliminarily into many smaller parts using the space sweep method and the minima rule. The preliminary partition is finally optimized using the greedy algorithm.
Findings
The skeleton of a 3D model can effectively represent a simplified version of the geometry of the 3D model. Using a model’s skeleton to partition the model is an efficient way. As it is generally desirable to have segmentations at concave creases and seams, the cutting position should be located in the concave region. The proposed approach can partition large models effectively to well retain the integrity of meaningful parts.
Originality/value
The proposed approach is new in the rapid prototyping field using the model skeletonization and the minima rule. Based on the authors’ knowledge, there is no method that concerns the integrity of meaningful parts for partitioning. The proposed method can achieve satisfactory results by the integrity of meaningful parts and assemblability for most 3D models.
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Jian Ding, Xiaotong Jiang, Yuchun Zou, Zhen Tang and Ziyang Zhen
A multivariable model reference adaptive control method is proposed to solve a distributed leader–follower formation control problem of unmanned aerial vehicles (UAVs) with…
Abstract
Purpose
A multivariable model reference adaptive control method is proposed to solve a distributed leader–follower formation control problem of unmanned aerial vehicles (UAVs) with uncertain parameters and unknown external disturbances for both leader and followers.
Design/methodology/approach
A case of uncertain stochastic external disturbances for UAVs is considered, and based on the distributed communication network of UAVs, a state-feedback adaptive controller is proposed to maintain the formation of UAVs consistently. Then, the stability and asymptotic tracking performance of the UAV formation control system are analyzed by the Lyapunov function.
Findings
The simulation results demonstrate that this formation control scheme can effectively solve the stochastic external disturbance problem of UAVs and ensure the stability of their formation.
Originality/value
The proposed multivariable model reference adaptive control method reduces the error of formation control system and improves the stability and control performance of UAV compared with fixed control.
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Shuai Yang, Wenjie Zhao, Yongzhen Ke, Jiaying Liu and Yongjiang Xue
Due to the inability to directly apply an intra-oral image with esthetic restoration to restore tooth shape in the computer-aided design system, this paper aims to propose a…
Abstract
Purpose
Due to the inability to directly apply an intra-oral image with esthetic restoration to restore tooth shape in the computer-aided design system, this paper aims to propose a method that can use two-dimensional contours obtained from the image for the three-dimensional dental mesh model restoration.
Design/methodology/approach
First, intra-oral image and smiling image are taken from the patient, then teeth shapes of the images are designed based on esthetic restoration concepts and the pixel coordinates of the teeth’s contours are converted into the vertex coordinates in the three-dimensional space. Second, the dental mesh model is divided into three parts – active part, passive part and fixed part – based on the teeth’s contours of the mesh model. Third, the vertices from the teeth’s contours of the dental model are matched with ones from the intra-oral image and with the help of matching operation, the target coordinates of each vertex in the active part can be calculated. Finally, the Laplacian-based deformation algorithm and mesh smoothing algorithm are performed.
Findings
Benefitting from the proposed method, the dental mesh model with esthetic restoration can be quickly obtained based on the intra-oral image that is the result of doctor-patient communication. Experimental results show that the quality of restoration meets clinical needs, and the typical time cost of the method is approximately one second. So the method is both time-saving and user-friendly.
Originality/value
The method provides the possibility to design personalized dental esthetic restoration solutions rapidly.
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Peng Zhu, Zixi Liu, Xiaotong Li, Xu Jiang and Mark Xuefang Zhu
Livestreaming, as a relatively new online marketing model, has generated numerous business opportunities for e-commerce and social commerce. The purpose of this paper is to…
Abstract
Purpose
Livestreaming, as a relatively new online marketing model, has generated numerous business opportunities for e-commerce and social commerce. The purpose of this paper is to investigate to what degree livestreaming content impacts online users' cognitive and emotional reactions and whether their cognitive and emotional responses affect their purchase intention.
Design/methodology/approach
Through the lens of regulatory focus theory (RFT) and stimulus–organism–response (S–O–R) theory, the authors empirically examine the influencing mechanisms of livestreaming on online consumers' purchase intentions. Structural equation models are used to analyze the relationships in the proposed research model.
Findings
The results of this study show that information-task fit positively affects consumers' perceived usefulness of livestreaming. Both visual effects and sociability positively affect consumers' perceived value and social presence. Furthermore, perceived usefulness and perceived joy positively affect consumers' purchase intentions in a livestreaming environment. This study’s results also demonstrate that the regulatory focus of consumers has a moderating effect on the influence of their perceived joy on shopping intentions.
Originality/value
This study contributes to the relevant literature by simultaneously examining the role of e-commerce platform characteristics and online consumer psychology in influencing behavioral intention. With a better understanding of their role, platform operators and sellers can refine their livestreaming marketing tools and strategies. Highlighting the interplays among external stimuli, user reactions and user motivational styles, this study contributes to mobile e-commerce literature and the broader literature on digital marketing and human–computer interaction.
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Xiaotong Liu, Tong Wen and Cen Qin
This paper aims to explore how typical personal, interpersonal and environmental factors influence entrepreneurs' growth aspirations by investigating the impact mechanism of…
Abstract
Purpose
This paper aims to explore how typical personal, interpersonal and environmental factors influence entrepreneurs' growth aspirations by investigating the impact mechanism of entrepreneurial competency and guanxi on the growth aspirations of small tourism entrepreneurs in a dynamic environment.
Design/methodology/approach
Applying social cognitive theory (SCT) and business growth theory (BGT), this research uses confirmatory factor analysis and structural equation modeling (SEM) based on the questionnaire survey data of 371 small tourism business owners/owner-managers to test the relationship between entrepreneurial competency, guanxi and growth aspirations, with self-efficacy as a mediator and environment dynamism as a moderator.
Findings
The findings indicate that entrepreneurial competency is a more direct and significant factor than guanxi in facilitating the entrepreneurial growth aspirations in small tourism enterprises (STEs). Entrepreneurial competency and guanxi can both enhance entrepreneurs' self-efficacy, which then affects their aspirations to grow their business. Self-efficacy is a critical predictor of entrepreneurs' growth aspirations in STEs, although its effect is weakened by environmental dynamism.
Originality/value
This study expands the integrated application of SCT and BGT in tourism context, providing a more comprehensive and nuanced interpretation of the growth aspirations of entrepreneurs in STEs. It sheds more light on the effect of different entrepreneurial capital on growth aspirations and provides managerial implications accordingly.
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Tiancheng Shang, Kaiti Shang, Peihong Liu, Xiaotong Sun and Xinxin Li
The purpose of this paper is to analyze the implicit prices of hotel attributes in different time periods and different markets.
Abstract
Purpose
The purpose of this paper is to analyze the implicit prices of hotel attributes in different time periods and different markets.
Design/methodology/approach
With data from the travel meta-search engine, this paper chose 3- to 5-star hotels in Beijing’s central business district and use hedonic price models.
Findings
The results suggest that the attributes with significant implicit prices differ in different time periods; the same attributes with different implicit prices in different time periods; the same attributes with different implicit prices in different market segments.
Originality/value
This study may help to explain the different findings on the relationship between the attributes and room rates of Chinese star-rated hotels in different time periods, and will be useful in both revenue optimization efforts and the design of new hotels projects.
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Ping Gui, Xiaotong Ji, Yanlan Mei and Zhicheng Quan
Community governance plays an important role in the prevention and control of the Coronavirus disease 2019 (COVID-19) pandemic in China. Community workers, the main executors in…
Abstract
Purpose
Community governance plays an important role in the prevention and control of the Coronavirus disease 2019 (COVID-19) pandemic in China. Community workers, the main executors in community governance, experience a huge amount of stress, which affects their physical and mental health. Thus, it is crucial to pay more attention to the stressors and stress responses of community workers and propose strategies to alleviate such responses. This paper aims to analyze the work stress of community workers during the COVID-19 pandemic in China.
Design/methodology/approach
Based on a questionnaire survey of 602 community workers during COVID-19 in China, the four main stressors and 14 stress factors of community workers were identified and six factors at three levels of stress responses were defined. A stress analysis model is proposed that tests the mediating role of psychological capital and the moderating role of organizational climate.
Findings
The results show that stressors influence stress responses through the moderating role of psychological capital, organizational climate plays a negative mediator role between stressors and psychological capital and the main stressors for community workers are work, safety and performance stress.
Originality/value
This paper contributes to existing research because it offers suggestions for reducing the impact of stress on the community workers during the COVID-19 pandemic. Further, it can promote the control and prevention of the COVID-19.
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Ling Chen, Zhi Su, Xiaotong He, Xiang Chen and Lin Dong
Embroidery as a textile embellishment technique plays an important role in people's daily life. Esthetic embroidery artworks possess cultural values. With the development of…
Abstract
Purpose
Embroidery as a textile embellishment technique plays an important role in people's daily life. Esthetic embroidery artworks possess cultural values. With the development of robotics and artificial intelligence (AI), these technologies have been studied and applied in the embroidery process. This study aims to survey how these technologies facilitate embroidery from different aspects.
Design/methodology/approach
This paper surveys how the technologies of robotics and AI are applied in the embroidery field. The applications are mainly reviewed from three aspects: computerized robotic embroidery systems has been widely used for the mass production of embroidered textiles, the advanced technological systems and techniques have greatly facilitated the development of smart textiles and the artificial intelligence plays an important role in the inheritance, innovation and protection of traditional handicraft artwork of embroidery.
Findings
The programmable robotic embroidery machines have greatly improved the production efficiency of embroidered textiles and promoted the development of electronic textiles. The AI, mainly the deep learning technology, brings significant benefits to esthetic embroidery creation. Technology-based embroidery has become a hot research topic in the field of textiles.
Originality/value
This paper summarizes the application of robotics and AI technologies in the field of embroidery, which provides readers a comprehensive and systematic understanding about the research progress of modern technology-oriented embroidery. This helps readers gain inspiration from the technology perspectives.
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Yuan Peng, Shengli Hou, Weifeng Zhai, Xiaofeng Yang, Hao He and Xiaotong Guo
This study aims to provide guidance for the reliability of electronic packaging. The reliability of solder joints at extremely temperature thermal shock is critical for electronic…
Abstract
Purpose
This study aims to provide guidance for the reliability of electronic packaging. The reliability of solder joints at extremely temperature thermal shock is critical for electronic equipment operating in the field of deep space exploration. In this study, the Sn3.0Ag0.5Cu (SAC305)/Cu solder joints were prepared and thermally shocked with temperatures ranging from −110°C to 110°C, to investigate the effects of extreme temperature thermal shock on the microstructural evolution and property deterioration of the solder joints.
Design/methodology/approach
The interfacial intermetallic compound (IMC) stress gradient was calculated through thermal stress theory, mechanism of voids/cracks initiation was clarified, and prediction of the service life was analyzed with the energy-based model.
Findings
It is found that the Ag3Sn, IMC and cracks/voids had evolved significantly with the increase in the cycle period. The microstructure of the IMC changed from short rod-like morphology to scallop shape, the voids in the Cu3Sn IMC layer continued to increase and integrate, forming larger diameter voids, etc. In addition, the shear strength of SAC305/Cu solder joints decreased gradually with the increase in thermal shock cycles, the fracture mode changes from ductile fracture mode to ductile-brittle mixed fracture mode after 500 cycles. The characteristic lifetime of the SAC305/Cu solder joints under the action of extreme thermal shock is about 1427.86 cycles.
Originality/value
This work provides guidance for the reliability of the solder joints at extremely temperature thermal shock.
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Min Cheng, Lin Liu, Xiaotong Cheng and Li Tao
Many waste-to-energy (WTE) plants are constructed and operated using the public-private partnership (PPP) mode in China. However, risk events of PPP WTE incineration projects…
Abstract
Purpose
Many waste-to-energy (WTE) plants are constructed and operated using the public-private partnership (PPP) mode in China. However, risk events of PPP WTE incineration projects sometimes occur. This study aims to clarify the relationship of risks in China's PPP WTE incineration projects and identify the key risks accordingly and risk transmission paths.
Design/methodology/approach
A risk list of PPP WTE incineration projects was obtained based on literature analysis. Moreover, a hybrid approach combining fuzzy sets, decision-making trial and evaluation laboratory (DEMATEL) and interpretive structural modeling (ISM) was developed to analyze the causality of risks, explore critical risks and reveal the risk transmission paths. The quantitative analysis process was implemented in MATLAB.
Findings
The results show that government decision-making risk, government credit risk, government supervision behavior risk, legal and policy risk, revenue and cost risk and management capacity risk are the critical risks of PPP WTE incineration projects in China. These critical risks are at different levels in the risk hierarchy and often trigger other risks.
Originality/value
Currently, there is a lack of exploration on the interaction between the risks of PPP WTE incineration projects. This study fills this gap by examining the key risks and risk transfer pathways of PPP WTE incineration projects from the perspective of risk interactions. The findings can help the public and private sectors to systematically understand the risks in PPP WTE incineration projects, thus enabling them to identify the risks that need to be focused on when making decisions and to optimize risk prevention strategies. The proposed hybrid approach can offer methodological ideas for risk analysis of other types of PPP projects.