Xiao-Shun Zhao, Li Yu, Xue Yang and Si-Yu Zhang
The purpose of this study was to develop a new folding method for modeling complicated folded fabric with surfaces of revolution.
Abstract
Purpose
The purpose of this study was to develop a new folding method for modeling complicated folded fabric with surfaces of revolution.
Design/methodology/approach
Irregular wrinkles and mesh distortions easily appear in the fold modeling of a complex curved surface. Aimed at this key technical problem, the segmentation mapping folding method (SMFM) is proposed in this paper. First, high-precision flattened planes were obtained by using segmentation mapping techniques. Second, the segmented planes were transformed into a folded and continuous geometric model by using matrix transformations. Finally, initial stress was used to modify the geometric folding errors, which ensured agreement with the inflated flexible fabric’s geometry and the original design.
Findings
Compared with the traditional folding method, SMFM has the advantages of good finite-element mesh quality, large radial compression rate, regular folds, etc. The surface area error and the volume error of the inflated single torus established by SMFM were only 1.2 per cent, showing that SMFM has high modeling accuracy. The numerical results of an inflatable re-entry vehicle are presented to demonstrate the reliability, feasibility and applicability of SMFM. Moreover, the stress modification reduced the problems of stress concentration and mesh distortions, improving the accuracy and stability of the numerical calculations.
Originality/value
In this paper, for the first time, a folding method for modeling complicated folded fabric is proposed. This methodology can be used to model the multidimensional compression and regular folds of complex surfaces of revolution that cannot be flattened and to improve the accuracy and stability of the numerical calculations.
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Heng Xiao, Wei-Hao Yan, Lin Zhan and Si-Yu Wang
A new and explicit form of the elastic strain-energy function for modeling large strain elastic responses of soft solids is constructed based on Hencky's logarithmic strain tensor.
Abstract
Purpose
A new and explicit form of the elastic strain-energy function for modeling large strain elastic responses of soft solids is constructed based on Hencky's logarithmic strain tensor.
Design/methodology/approach
Well-designed invariants of the Hencky strain are introduced for characterizing deformation modes and, furthermore, a new interpolating technique is proposed for combining piecewise splines into a single smooth function.
Findings
With this new form and this new technique, objectives in three respects may be achieved for the first time.
Originality/value
First, no adjustable parameters need to be treated. Second, large strain responses for three benchmark modes are derivable in a decoupled sense without involving strongly nonlinear coupling effects. Finally, large strain data may be automatically and accurately matched for three benchmark modes, including uniaxial, equi-biaxial and plane-strain extension. Numerical examples are presented and compared with usual approaches.
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Heng Xiao, Zi-Tao Li, Lin Zhan and Si-Yu Wang
The purpose of this study is to show how gradual strength degradation of metal beams under cyclic bending up to fatigue failure is simulated based on a new elastoplasticity model…
Abstract
Purpose
The purpose of this study is to show how gradual strength degradation of metal beams under cyclic bending up to fatigue failure is simulated based on a new elastoplasticity model free of any yield criterion.
Design/methodology/approach
A new approach is proposed toward accurately and explicitly prescribing evolution of non-uniform stress distribution on beam cross-section under cyclic bending and, as such, gradual degradation of the bending strength can be directly determined.
Findings
Explicit results for the bending response in a whole cyclic process up to fatigue failure are obtained and the fatigue characteristic curve is for the first time simulated directly between the curvature amplitude and the cycle number to failure.
Originality/value
First, explicit and accurate determination of the non-uniform stress distribution on beam cross-section is achieved with asymptotic softening effects. Second, degradation of the bending strength can be directly deduced cycle by cycle. Finally, the relationship between the bending moment and the curvature is calculated using new and efficient numerical algorithms, thus bypassing usual time-consuming calculations with finite element procedures. Numerical results are presented and in good agreement with experimental data.
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Building social capital between groups of people and developing social enterprises that integrate social goals into commercial business models are rapidly adopted as innovative…
Abstract
Building social capital between groups of people and developing social enterprises that integrate social goals into commercial business models are rapidly adopted as innovative poverty relief mechanisms across countries. Together, the translation of social relationships into increased accessibility to resources, and the entrepreneurial dynamics resulting in additional services and goods, are thought to meet the survival and developmental needs of poor families and communities. However, the socio-economic contexts, in which new public policies and initiatives have been taken, vary from country to country. In China, its strong Confucian culture, state-led development strategy, weak civil society, and hierarchical social relationships have contributed to a value structure of social capital, but decreased the efficiency of business practice in social enterprise. This chapter presents a case study of Rural Cooperative Program, a poverty relief initiative in China’s southwest Guizhou Province. With the introduction of China’s new policies in welfare and rural development, this chapter presents evaluation results of whether social enterprises and entrepreneurship can improve poor villagers’ socio-economic wellbeing and promote sustainable development of poor rural villages in China, and to what extent social capital has been mobilized to facilitate the Rural Cooperative Program.
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Zi-Han Xu, Lin Zhan, Si-Yu Wang, Hui-Feng Xi and Heng Xiao
A new approach is proposed toward accurately matching any given realistic hardening and softening data from uniaxial tensile test up to failure and moreover, toward bypassing…
Abstract
Purpose
A new approach is proposed toward accurately matching any given realistic hardening and softening data from uniaxial tensile test up to failure and moreover, toward bypassing usual tedious implicit trial-and-error iterative procedures in identifying numerous unknown parameters.
Design/methodology/approach
Finite strain response features of metals with realistic hardening-to-softening transition effects up to eventual failure are studied for the first time based on the self-consistent elastoplastic J2-flow model with the logarithmic stress rate. As contrasted with usual approximate and incomplete treatments merely considering certain particular types of hardening effects such as power type hardening, here a novel and explicit approach is proposed to obtain a complete form of the plastic-work-dependent yield strength over the whole hardening and softening range.
Findings
A new multi-axial evolution equation for both hardening and softening effects is established in an explicit form. Complete results for the purpose of model validation and prediction are presented for the finite strain responses of monotonic uniaxial stretching up to failure.
Originality/value
New finite strain elastoplastic equations are established with a new history-dependent variable equivalently in place of the usual plastic work. With these equations, a unified and accurate simulation of both gardening and softening effects up to failure is achieved for the first time in an explicit sense without involving usual tedious implicit trial-and-error iterative procedures.
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Yun Zhang, Xiaogang Chen, Xinhui Liu and Nan Zhu
With the development of information technology, there is a growing trend for internet enterprises in China to launch internet-only banks. This paper aims to explore how the brand…
Abstract
Purpose
With the development of information technology, there is a growing trend for internet enterprises in China to launch internet-only banks. This paper aims to explore how the brand trust in an internet enterprise is transferred to the initial trust in its affiliated internet-only bank and how such transfer affects adoption behavior of potential internet-only banking users.
Design/methodology/approach
Data were obtained from online questionnaires via a well-known Chinese survey website and a popular Chinese social platform, which yielded 486 usable responses for the analysis. Partial least squares was used for testing hypotheses.
Findings
The results show that brand trust in the internet enterprise increases initial trust in its affiliated internet-only bank. This, in turn, enhances the adoption of internet-only banking. More importantly, these results show that brand trust in the internet enterprise transfers to initial trust in internet-only banking through performance expectancy and perceived risk. Further, the need for interaction moderates the relationship between brand trust and performance expectancy as well as the relationship between brand trust and perceived risk.
Originality/value
This study provides new insights into the mechanism by which trust is transferred between two affiliated business entities. The results of the study suggest several useful managerial implications for managing the internet-only banks.
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Xinyan Lv, Yisheng Liang, Jiang Zhong and Haifeng He
The silicone modifications of two-component epoxy resin coatings are commonly built on epoxy resins rather than on epoxy curing agents. The silicone-modified epoxy curing agent…
Abstract
Purpose
The silicone modifications of two-component epoxy resin coatings are commonly built on epoxy resins rather than on epoxy curing agents. The silicone-modified epoxy curing agent system is rarely reported yet. This study aims to prepare the polysiloxane (PS)-modified waterborne epoxy coatings based on aqueous curing agents technology.
Design/methodology/approach
Waterborne epoxy curing agents with different contents of terminal epoxy PS were synthesized by reacting with triethylenetetramine, followed by incorporating of epoxy resin (NPEL-128) and polyethylene glycol diglycidyl ether. The waterborne epoxy coatings were prepared with the above curing agents, and their performance was investigated through thermogravimetric analysis, scanning electron microscopy, mechanical characterization, gloss measurement, chemical resistance test and ultraviolet (UV) aging experiment.
Findings
The results showed that the epoxy coating prepared by silicon-modified curing agent has higher gloss, better chemical resistance and UV resistance than the coating from unmodified curing agent with terminal epoxy PS and commercially available waterborne epoxy curing agent (Aradur 3986), as well as the competitive mechanical properties and heat resistance. Reduced water absorption on fibrous paper was also obtained with the help of silicon-modified curing agent.
Originality/value
These findings will be valuable for resin researchers in addressing the modification issues about waterborne epoxy resin and curing agent.