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This study aims to investigate mixed lubrication performances of stern bearing in a misaligned state considering turbulence and bearing deformation impacts.

A mixed lubrication model of stern bearing is established. The generalized average Reynolds equation governing the turbulent flow of lubricant is analyzed by considering the interaction of bearing elastic deformation, asperity contact pressure and film pressure. The bearing behaviors including minimum film thickness, hydrodynamic pressure, asperity friction force and frictional coefficient are studied under different models. The correctness of this model is verified by comparing it with that of the published data.

Numerical results indicate that elastic deformation noticeably decreases the maximum film pressure, the asperity contact force and the friction coefficient in the mixed lubrication stage. The effect of elastic deformation and turbulence reduces the transition speed from mixed to liquid lubrication.

This model includes both turbulence and bearing deformation impacts on journal bearing performances. It is expected that the numerical results can provide useful information to establish a stern bearing exposed to mixed lubrication conditions.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2022-0352/

To solve the obstacle detection problem in robot autonomous obstacle negotiation, this paper aims to propose an obstacle detection system based on elevation maps for three types of obstacles: positive obstacles, negative obstacles and trench obstacles.

The system framework includes mapping, ground segmentation, obstacle clustering and obstacle recognition. The positive obstacle detection is realized by calculating its minimum rectangle bounding boxes, which includes convex hull calculation, minimum area rectangle calculation and bounding box generation. The detection of negative obstacles and trench obstacles is implemented on the basis of information absence in the map, including obstacles discovery method and type confirmation method.

The obstacle detection system has been thoroughly tested in various environments. In the outdoor experiment, with an average speed of 22.2 ms, the system successfully detected obstacles with a 95% success rate, indicating the effectiveness of the detection algorithm. Moreover, the system’s error range for obstacle detection falls between 4% and 6.6%, meeting the necessary requirements for obstacle negotiation in the next stage.

This paper studies how to solve the obstacle detection problem when the robot obstacle negotiation.

The purpose of this paper is to study the effect of vapor assembly sequence and assembly temperature on the corrosion protection of the complex silane films Al alloy. The performance and application range of silane films are enhanced.

The complex silane films were successfully prepared on the surface of aluminum alloy using via vapor phase assembly of 1,2,3-benzotriazole (BTA) and dodecyltrimethoxysilanes (DTMS). The protection of the assembly films against corrosion of Al alloy is investigated by the electrochemical measurements and the alkaline solution accelerated corrosion test. Thickness and hydrophobicity of the complex films are studied using ellipsometric spectroscopy and contact angle tests.

It shows that the anti-corrosion ability of the complex films is overall superior to that of the single-component assembled films. DTMS-BTA films have larger thickness and best anti-corrosion ability. The alkyl chains in DTMS have better compatibility with BTA molecules. The rigid BTA molecule can permeate into the long alkyl chain of DTMS as fillers and improve the barrier properties of the complex films.

In this paper, a green and efficient method of vapor phase assembly is proposed to rust prevention during manufacture of Al alloy workpiece.

The aim of this paper is to solve the toxic and harmful problems caused by traditional volatile corrosion inhibitor (VCI) and to analyze the effect of the layered structure on the enhancement of the volatile corrosion inhibition prevention performance of amino acids.

The carbon dots-montmorillonite (DMT) hybrid material is prepared via hydrothermal process. The effect of the DMT-modified alanine as VCI for mild steel is investigated by volatile inhibition sieve test, volatile corrosion inhibition ability test, electrochemical measurement and surface analysis technology. It demonstrates that the DMT hybrid materials can improve the ability of alanine to protect mild steel against atmospheric corrosion effectively. The presence of carbon dots enlarges the interlamellar spacing of montmorillonite and allows better dispersion of alanine. The DMT-modified alanine has higher volatilization ability and an excellent corrosion inhibition of 85.3% for mild steel.

The DMT hybrid material provides a good template for the distribution of VCI, which can effectively improve the vapor-phase antirust property of VCI.

The increased volatilization rate also means increased VCI consumption and higher costs.

Provides a new way of thinking to replace the traditional toxic and harmful VCI.

For the first time, amino acids are combined with nano laminar structures, which are used to solve the problem of difficult volatilization of amino acids.

The purpose of this paper is to investigate the combined erosion and corrosion behavior of WC-Ni vacuum brazed coating.

Al₂O₃ particles and 10 wt% NaCl solution are used to evaluate erosion and corrosion resistance of WC-Ni vacuum brazed coating. Combined test of erosion and corrosion is also conducted. The microstructure of each specimen is characterized by the scanning electron microscopy. The chemical composition was determined by energy-dispersive X-ray spectroscopy.

WC-Ni vacuum brazed coating layer is effective protective coating under combined erosion and corrosion environment. The weight loss of coating layer is more reduced as the cumulative test time.

WC-Ni vacuum brazed coatings are investigated to check characteristic of the combined erosion and corrosion environment. WC-Ni vacuum brazed coatings are kind of diffusion coating that attract attention because of the resistance of superb impact and corrosion in comparison with other coatings. Some previous researches reported the properties of vacuum brazed WC material. Erosion and corrosion behaviors of WC-Ni vacuum brazed coatings were studied in our previous research, respectively. Hence, in this research, the principal objective is to examine the combined erosion and corrosion behavior of WC-Ni vacuum brazed coating.

This paper aims to examine the association between green innovation and the cost of equity in China. This study relies on the investors’ base perspective and shareholders’ perceived risk perspective to investigate the relation between green innovation and the cost of equity in China.

The paper uses firm-fixed effect regression for a sample of Chinese public companies for the period 2008–2018.

The authors find a negative relationship between green innovation and the cost of equity capital. This negative association is found to be more pronounced for less financially constrained firms, during periods of high economic policy uncertainty, and for firms with a strong internal control environment. Finally, the paper shows that the negative association became more pronounced after the passage of the Environmental Protection Law of China in 2012. The results remain robust to possible endogeneity concerns.

This study contributes to the green innovation literature by documenting that shareholders favorably view firms implementing green innovation policies. The study also has policy implications for Chinese regulators in improving the green credit policy.

Shanghai ANE Logistics Co., Ltd., established on June 1, 2010, is a business of road part-load logistics for goods from 5 to 300 kilograms. Mr. Wang Yongjun and his management team have spent five consecutive years building ANE into the biggest part-load franchising network in China, and set up a brand new business model, through integration of traditional transport lines, part-load express network and information technology platform.

This chapter focused on presenting the result of the Delphi study from the questionnaire distributed to the experts. The Delphi technique was used for modelling the construction supply chain management (CSCM) practice in the fourth industrial revolution (4IR) era. The technique was also used to predict the supply chain management's (SCM) possible trends in the construction industry. A total of 15 experts were selected for this study based on their working experience. The Delphi study also validated the gaps (organisational culture and 4IR component) identified from the existing CSCM model. The findings from the Delphi study revealed that organisational culture has a significant impact on the practice of CSCM in the 4IR era. Regarding adopting the 4IR component for the CSCM in Nigeria, the Delphi study revealed that smart management and virtualisation are the most adopted. Unfortunately, the cyber-physical system, the heartbeat of the 4IR, is yet to be fully implemented for CSCM practice in the Nigerian construction industry.

Discusses housing reform and its impact on the governance of housing in China. The roles of the state and work units have been shifted from providers to enablers in the market of housing supply after the introduction of privatisation and the market mechanism. However, the role of work units in housing distribution remains almost intact. The scope of work units’ influence is more extensive than before reform. The involvement of work units as mediators in the housing market affects the performance of the market and contributes to the fluctuations and uncertainty of the market. In order to tackle the new problems arising from reform, the role of work units needs to be redefined.

This chapter aimed to uncover the gaps in the existing construction supply chain management (CSCM) models. Organisational culture and the fourth industrial revolution (4IR) components are the two gaps that were identified through reviewing existing CSCM models. The 4IR is driven by three components which are smart management, virtualisation and cyber-physical system. It was proposed in this chapter that the practice of CSCM should be in tandem with the components of 4IR. This chapter recommended that for the effective practice of the construction supply chain (CSC) in the 4IR era, construction stakeholders should adopt an innovative and collaborative organisational culture. The organisational culture adopted by a construction firm performs a crucial role in encouraging construction stakeholders in adopting 4IR components for CSCM. Each of the 4IR components is driven by technologies like autonomous robots, building information modelling (BIM), radio frequency identification (RFID), the internet of things (IoT) and others. Among all the technologies, it was discovered that RFID and BIM had gained prominence in most CSC literature. The chapter recommended that blockchain, digital twins and the cyber-physical system are the next trending technology for CSCM.