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The purpose of this study is to design a closed hydrostatic guideway has the ability to resist large-side load, pitch moments and yaw moments, has good stiffness and damping characteristics, and provides certain beneficial guidance for the design of large-span closed hydrostatic guideway on the basis of providing a large vertical load bearing capacity.

The Reynolds’ equation and flow continuity equation are solved simultaneously by the finite difference method, and the perturbation method and the finite disturbance method is used for calculating the dynamic characteristics. The static and dynamic characteristics, including recess pressure, flow of lubricating oil, carrying capacity, pitch moment, yaw moment, dynamic stiffness and damping, are comprehensively analyzed.

The designed closed hydrostatic guideway has the ability to resist large lateral load, pitch moment and yaw moment and has good stiffness and damping characteristics, on the basis of being able to provide large vertical carrying capacity, which can meet the application requirements of heavy two-plate injection molding machine (TPIMM).

This paper researches static and dynamic characteristics of a large-span six-slider closed hydrostatic guideway used in heavy TPIMM, emphatically considering pitch moment and yaw moment. Some useful guidance is given for the design of large-span closed hydrostatic guideway.

This paper aims to establish an accurate mathematical model of a piezoelectric membrane restrictor that can be applied to control the shaft’s centerline orbit.

The methodology uses three coupled equations to establish a mathematical model of the piezoelectric membrane restrictor – Reynolds equation, the membrane deformation equation and the flow rate equation. A data identification method is used to propose the flow rate formulas for the piezoelectric membrane restrictor.

It has been found that the structural parameters, the membrane center deformation and the inlet and outlet pressures of the piezoelectric membrane restrictor have an effect on the static performance of the restrictor. The identified flow rate result of the piezoelectric membrane restrictor is consistent with the models.

The paper provides an accurate mathematical model of the piezoelectric membrane restrictor which can also be applied to other membrane restrictors.

This paper aimed to introduce a systematic body of knowledge via a scientometric review, guiding the sustainable transition from conventional construction to prefabricated construction. The construction industry currently faces a challenge to balance sustainable development and the construction of new buildings. In this context, one of the most recent debates is prefabricated construction. As an emerging construction approach, although existing knowledge makes contributions to the implementation of prefabricated construction, there is a lack of a comprehensive and in-depth overview of the critical knowledge themes and gaps.

This study uses the scientometric analysis to review the state-of-the-art knowledge of prefabricated construction. It retrieved data from the Web of Science core collection database. CiteSpace software was used to conduct the analysis and visualization; three analysis methods identify the knowledge hotspots, knowledge domains and knowledge topics. Finally, according to integrating the hidden connections among results, a body of knowledge for prefabricated construction application can be inferred.

The results show that 120 knowledge hotspots, five critical knowledge domains and five prominent knowledge topics are vital for promoting implementation of prefabricated construction. Based on the afore analysis, a body of knowledge for prefabricated construction that can systematically cover a broad knowledge of prefabricated construction-related research and activities are integrated and proposed in this paper.

Body of knowledge systematically covers a broad knowledge of prefabricated construction applications and is vital to guide researchers and practitioners to conduct related research and activities, thereby promoting the sustainable transition to prefabricated construction implementation.

This paper aims to clarify the impact of information asymmetry on users' payment rates and examine the role of perceived uncertainty (PU) and acceptable price (AP) in the relationship between information asymmetry and users' payment rates.

To test the influences of information asymmetry on users' payment rates, this paper collects 18,489 transaction data from the Chinese knowledge payment platform Zhihu with a Python crawler. This paper constructs a mediation model to define the relationship between information asymmetry and users' payment rates by introducing PU and AP as the mediators.

Information asymmetry negatively affects users' payment rates. In addition, PU and AP mediate the information asymmetry in users' payment rates bond.

This study only explores the mediators of the information asymmetry users’ payment rates bond, ignoring the effect of potential moderators, which would be an important direction for future research.

The findings of this paper suggest that information communication is essential in knowledge market transactions. Knowledge providers, as well as knowledge platforms, should enhance information exchange with consumers in order to increase product sales.

This paper provides a new perspective for understanding how information asymmetry affects users' payment rates and helps to guide suppliers to improve product quality. The research framework of this paper is universal to a certain extent.

This paper is one of the first to propose using PU and AP to construct a mediation model to study the information asymmetry between users' payment rates relationship. It provides a new perspective for understanding the channel of information asymmetry in customer behavior.

This paper aims to propose a solution for dissolving the “privacy paradox” in social networks, and explore the feasibility of adopting a synergistic mechanism of “deep-learning algorithms” and “differential privacy algorithms” to dissolve this issue.

To validate our viewpoint, this study constructs a game model with two algorithms as the core strategies.

The “deep-learning algorithms” offer a “profit guarantee” to both network users and operators. On the other hand, the “differential privacy algorithms” provide a “security guarantee” to both network users and operators. By combining these two approaches, the synergistic mechanism achieves a balance between “privacy security” and “data value”.

The findings of this paper suggest that algorithm practitioners should accelerate the innovation of algorithmic mechanisms, network operators should take responsibility for users’ privacy protection, and users should develop a correct understanding of privacy. This will provide a feasible approach to achieve the balance between “privacy security” and “data value”.

These findings offer some insights into users’ privacy protection and personal data sharing.

This paper aims to study the effects of MnO₂ on the ZnO–Bi₂O₃-based varistor prepared via flash sintering (FS)

MnO₂-doped ZnO–Bi₂O₃-based varistors were successfully prepared by the FS with a step-wise increase of the .current in 60 s at the furnace temperature <750°C under the direct current electric field of 300 V cm⁻¹. The FS process, microstructure and the electrical performance of ZnO–Bi₂O₃-based varistors were systematically investigated.

The doping of MnO₂ significantly decreased the onset temperature of FS and improved the electrical performance of FS ZnO varistor ceramic. The sample with 0.5 mol% MnO₂ doping shows the highest improvement, with the nonlinear coefficient of 18, the leakage current of 16.82 µA, the threshold voltage of 459 V/mm and the dielectric constant of 1,221 at 1 kHz.

FS is a wonderful technology to enhance ZnO varistors for its low energy consumption, and a short sintering time can reduce grain growth and inhabit Bi₂O₃ volatilize, yet few research studies work on that. In this research, the authors analyzed the FS process and improved the electrical characteristics through MnO₂ doping.

This study aims to identify senior citizens’ requirements related to “embedded retirement facilities (ERFs)”, which are small-scale, multi-functional and community-based care facilities for senior citizens in mainland China, and to discuss whether senior citizens’ perceptions are influenced by their backgrounds.

A questionnaire type of research was administrated to gain senior citizens’ rankings of services that should be provided by ERFs. Non-parametric statistical models were applied to analyse the collected data.

Results reveal that health care services for senior citizens are considered the most important. Requirements regarding rehabilitation and entertainment and daily life assistance are ranked second and third, respectively. Culture-related activities are the least important. Differences in the senior citizens’ background also influence their choices.

This research is based on a questionnaire survey completed in northeast China. Opinions from other areas of mainland China will be collected in the future study. Furthermore, the key items identified in this research, which was completed by participants from the built environment discipline, can be further elaborated by combining interdisciplinary feedback.

This study explores services that are supposedly provided by ERFs. Findings will provide useful perceptions from senior citizens and will enable decision makers to prioritise services for senior citizens.

Although senior citizens are the end users of ERFs, their needs are easily overlooked. This study calls attention to their needs from ERFs, and the results are likely to serve as references for stakeholders in building improved facilities.

ERFs have been provided in mainland China to cater to senior citizens’ needs since 2014. However, few studies have identified senior citizens’ requirements for provided services. The survey-based results of this work will serve as references for various stakeholders in making enhanced decisions.

The purpose of this paper is to provide a review of recent systematic and comprehensive advancement in electrospun polymer fiber and their composites with shape memory property.

The nanofiber manufacture technique is initially reviewed. Then, the influence of electrospinning parameters and actuation method has been discussed. Finally, the study concludes with a brief review of recent development in potential applications.

Shape memory polymer (SMP) nanofibers are a type of smart materials which can change shape under external stimuli (e.g. temperature, electricity, magnetism, solvent). In general, such SMP nanofibers could be easily fabricated by mature electrospinning technique. The nanofiber morphology is mainly affected by the electrospinning parameters, including applied voltage, tip-to-collector distance, viscosity of solution, humidity and molecular weight. For actuation method, most SMP nanofibers and their composites can change their shapes in response to heat, magnetic field or solvent, while few can be driven by electricity. Compared with the block SMPs, electrospun SMP nanofibers’ mat with porosity and low mechanical property have a wide potential application field including tissue engineering, drug delivery, filtration, catalysis.

This paper provides a detailed review of shape memory nanofibers: fabrication, actuation and potential application, in the near future.

This paper aims to present a phenomenological model to investigate the underlying mechanism and predict the bio-inspired performance under different thermo-temporal conditions.

Flory-Rehner free-energy functions are applied to quantitatively identify the driving forces in the viscously bio-inspired response of a dynamic polymer network. Furthermore, the permeation transition equation is adopted to couple water gradient and water sorption/desorption into the free-energy function.

The results show that the influence of potential energy on deformation can be related to a stretching ratio that uniquely determines water sorption/desorption, locomotion frequency and contractile stress. Finally, by means of combining the free-energy function and Arrhenius equation, a phenomenological thermo-temporal model is developed and verified by the experimental results.

This study focuses on exploring the theoretical mechanism and significantly enhances understanding of relevant experimental features reported previously.

The outcome of this study will provide a powerful phenomenological and quantitative tool for study on shape memory effect in bio-inspired polymers.

The ascendancy of modular offsite construction (MOSC) over traditional construction methods is well known. Despite the known potential of this construction approach, its adoption is minimal in New Zealand construction industry. This article investigates the potential benefits of using MOSC for delivery of high-rise buildings in New Zealand, underlying factors responsible for its low uptake and the measures that can facilitate its improved uptake.

This study utilised a mixed research approach. An empirical questionnaire survey was carried out with New Zealand construction industry professionals with expertise in MOSC. Factor analysis of survey data was carried out using SPSS software. Semi-structured interviews were carried out with subject matter experts to get further insights and expand the survey findings. Interview data were analysed using thematic analysis.

Study identified benefits of MOSC, thus establishing potential of its uptake for high-rise building construction. Constraining factors were investigated, most pronounced being low level of skills in construction industry to design, manufacture and integrate supply chain of MOSC, high initial investment, high cost of importing modules and negative perception about offsite manufactured buildings. This study also highlighted the enablers to improve uptake of MOSC. These enablers included; loan and mortgage policies to suit MOSC paradigm, building regulations to support OSC industry, increased support from the government and awareness and acceptance of standardised building designs among the clients.

Originality of this paper harps from little to no research carried out to investigate use of MOSC for high-rise buildings in New Zealand context.