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The purpose of this study is to investigate the effectiveness of a composite lubrication system combining polytetrafluoroethylene (PTFE) film and oil lubrication in steel–steel friction pairs.

A PTFE layer was sintered on the surface of a steel disk, and a lubricant with additives was applied to the surface of the steel disk. A friction and wear tester was used to evaluate the tribological properties and insulation capacity. Fourier transform infrared spectrometer was used to analyze the changes in the composition of the lubricant, and X-ray photoelectron spectroscopy was used to analyze the chemical composition of the worn surface.

It was found that incorporating the PTFE film with PSAIL 2280 significantly enhanced both the friction reduction and insulation capabilities at the electrical contact interface during sliding. The system consistently achieved ultra-low friction coefficients (COF < 0.01) under loads of 2–4 N and elucidated the underlying lubrication mechanisms.

This work not only confirm the potential of PTFE films in insulating electrical contact lubrication but also offer a viable approach for maintaining efficient and stable low-friction wear conditions.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-06-2024-0222/

The purpose of this paper is to study how to effectively allocate water, energy and food (WEF) resources in urban development.

An agent-based model combined with NetLogo simulation model has been used in this paper.

This paper proposes a framework for agent analysis in urban WEF consumption.

Further discussions using empirical data are of great importance.

Apply to form the development model of the city in the future.

A new method of WEF management has been used at the city level.

Entrepreneurial passion is constantly considered a core driver of the entrepreneurial process. In reality, however, many passionate entrepreneurs still fail to persist in their ventures. Whether entrepreneurial passion negatively affects entrepreneurial persistence is not well known. The current study explores how entrepreneurial passion inhibits entrepreneurial persistence based on self-regulation theory. The moderating role of the perceived entrepreneurial institutional environment on the relationship is further investigated.

The study collected data from 200 entrepreneurs using a two-stage questionnaire. In the first stage, demographic information was obtained from the respondents, and their entrepreneurial passion, self-regulatory assessment mode and perceived entrepreneurial institutional environment were measured. Three months later, in the second stage, entrepreneurial persistence was evaluated.

The results show that entrepreneurial passion has a positive effect on self-regulatory assessment mode. Further, self-regulatory assessment mode negatively impacts entrepreneurial persistence and mediates the negative relationship between entrepreneurial passion and persistence. In addition, the greater the perceived level of the entrepreneurial institutional environment is, the weaker the positive association between entrepreneurial passion and self-regulatory assessment mode and the weaker the mediating effect of self-regulatory assessment mode on the relationship between entrepreneurial passion and entrepreneurial persistence and vice versa.

This paper clarifies the unknown negative effects of entrepreneurial passion, contributes to the theoretical relationship between the constructs of entrepreneurial passion and persistence and provides insights for decision-making by entrepreneurs, government and venture capital institutions.

This paper aims to improve the kinematic modeling accuracy of a spatial three-degrees-of-freedom compliant micro-motion parallel mechanism by proposing a modified modeling method based on the structural matrix method (SMM).

This paper analyzes the problem that the torsional compliance equation of the circular notched hinge is no longer applicable because it is subject to bilateral restrained torsion. The torsional compliance equation is modified by introducing the relative length coefficient. The input coupling effect, which is often neglected, is considered in kinematic modeling. The symbolic expression of the input coupling matrix is obtained. Theory, simulation and experimentation are presented to show the validity of the proposed kinematic model.

The results show that the proposed kinematics model can improve the modeling accuracy by comparing the theoretical, finite element method (FEM) and experimental method.

This work provides a feasible scheme for CMPM kinematics modeling. It can be better applied to the optimization design based on the kinematic model in the future.

This study conducts a comparative study on the performance of reliability assessment methods based on adaptive surrogate models to accurately assess the reliability of automobile components, which is critical to the safe operation of vehicles.

In this study, different adaptive learning strategies and surrogate models are combined to study their performance in reliability assessment of automobile components.

By comparing the reliability evaluation problems of four automobile components, the Kriging model and Polynomial Chaos-Kriging (PCK) have better robustness. Considering the trade-off between accuracy and efficiency, PCK is optimal. The Constrained Min-Max (CMM) learning function only depends on sample information, so it is suitable for most surrogate models. In the four calculation examples, the performance of the combination of CMM and PCK is relatively good. Thus, it is recommended for reliability evaluation problems of automobile components.

Although a lot of research has been conducted on adaptive surrogate-model-based reliability evaluation method, there are still relatively few studies on the comprehensive application of this method to the reliability evaluation of automobile component. In this study, different adaptive learning strategies and surrogate models are combined to study their performance in reliability assessment of automobile components. Specially, a superior surrogate-model-based reliability evaluation method combination is illustrated in this study, which is instructive for adaptive surrogate-model-based reliability analysis in the reliability evaluation problem of automobile components.

As an advanced calculation methodology, reliability-based multidisciplinary design optimization (RBMDO) has been widely acknowledged for the design problems of modern complex engineering systems, not only because of the accurate evaluation of the impact of uncertain factors but also the relatively good balance between economy and safety of performance. However, with the increasing complexity of engineering technology, the proposed RBMDO method gradually cannot effectively solve the higher nonlinear coupled multidisciplinary uncertainty design optimization problems, which limits the engineering application of RBMDO. Many valuable works have been done in the RBMDO field in recent decades to tackle the above challenges. This study is to review these studies systematically, highlight the research opportunities and challenges, and attempt to guide future research efforts.

This study presents a comprehensive review of the RBMDO theory, mainly including the reliability analysis methods of different uncertainties and the decoupling strategies of RBMDO.

First, the multidisciplinary design optimization (MDO) preliminaries are given. The basic MDO concepts and the corresponding mathematical formulas are illustrated. Then, the procedures of three RBMDO methods with different reliability analysis strategies are introduced in detail. These RBMDO methods were proposed for the design optimization problems under different uncertainty types. Furtherly, an optimization problem for a certain operating condition of a turbine runner blade is introduced to illustrate the engineering application of the above method. Finally, three aspects of future challenges for RBMDO, namely, time-varying uncertainty analysis; high-precision surrogate models, and verification, validation and accreditation (VVA) for the model, are discussed followed by the conclusion.

The scope of this study is to introduce the RBMDO theory systematically. Three commonly used RBMDO-SORA methods are reviewed comprehensively, including the methods' general procedures and mathematical models.

The purpose of this study is to prepare trivalent chromium conversion (TCC) film on the Zn-Ni electrodeposited film on the surface of 2024 aluminum alloy and to ensure that the TCC film has good corrosion resistance and electrical conductivity.

The morphology of the TCC film was studied by scanning electron microscopy, and the elemental composition of the TCC film was characterized by X-ray energy dispersive spectroscopy. The TCC film was tested and the roughness was analyzed by 3D morphology (white light interference). The electrochemical behavior and corrosion resistance of TCC films were studied by the Tafel polarization curve and electrochemical impedance spectroscopy, and the conductivity was tested.

The TCC films were uniformly black and bright in appearance and were mainly compounds of Zn, Ni and Cr with O. The electrochemical impedance of the TCC film is larger than that of the Zn-Ni film, the corrosion current (I_corr) is smaller than that of the Zn-Ni film and the corrosion potential (E_corr) is larger than that of the Zn-Ni film, which has excellent corrosion resistance. TCCs were performed on the appropriate size of the shell sample, and the resistance of the shells was 1.5 mVDC, which meets the total resistance requirements of the test standard for composite connector accessories.

In this study, TCC film was successfully prepared on the Zn-Ni coating on the surface of 2024 aluminum alloy. The TCC film has good corrosion resistance and electrical conductivity.

The purpose of this paper is to examine the joint congruence effect of leadership styles and organizational culture on project members’ innovative behaviors in the construction projects setting.

The proposed hypotheses are tested using polynomial regression with a sample of 217 project managers and employees of different construction projects in China, and plotted through response surface analysis.

The results of polynomial regressions support the congruence effect hypothesis, indicating that more innovative behaviors of the project members could be elicited by a high level of congruence between transformational or transactional leadership styles and organizational culture. Furthermore, asymmetrical incongruence effects are found wherein project members with lower levels of innovative behaviors when project organizational culture is stronger as compared with when two leadership styles are at higher levels. Specifically, the condition is found under the innovation dimension of organization culture, but higher level of innovative behavior conversely displays when the harmony culture is weaker than two leadership styles.

The conceptual model and hypotheses are examined by analyzing cross-sectional and self-reported data collected in China. The findings could be further examined through multi-source or longitudinal, more systematic research.

The findings highlight the pivotal role played by the value congruence of leaders-organizations in motivating employees to be innovative in project organizations. This paper provides knowledge for project managers to help them understand whether and how project members’ innovative behaviors are better motivated by the fit or misfit between the styles of leadership and project organizational cultures. Besides, this study provides the approach or direction for the project leaders training.

This study is one of the first to examine the joint effects of leadership styles and organizational culture on innovative behavior based on the person-organization fit theory and from the perspective of value congruence.

This study aims to obtain the more precise decision map to fuse the source images by Coefficient significance method. In the area of multifocus image fusion, the better decision map is very important the fusion results. In the processing of distinguishing the well-focus part with blur part in an image, the edge between the parts is more difficult to be processed. Coefficient significance is very effective in generating the better decision map to fuse the multifocus images.

The energy of Laplacian is used in the approximation coefficients of redundant discrete wavelet transform. On the other side, the coefficient significance based on statistic property of covariance is proposed to merge the detail coefficient.

Due to the shift-variance of the redundant discrete wavelet and the effectiveness of fusion rule, the presented fusion method is superior to the region energy in harmonic cosine wavelet domain, pixel significance with the cross bilateral filter and multiscale geometry analysis method of Ripplet transform.

In redundant discrete wavelet domain, the coefficient significance based on statistic property of covariance is proposed to merge the detail coefficient of source images.