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The purpose of this paper is to study the tribological properties of Cu nanoparticles (NPs) as lubricant additives in three kinds of commercially available lubricants.

A four-ball machine is used to estimate the tribological properties of Cu NPs as lubricant additives in three kinds of commercially available lubricants. Three-dimensional optical profiler and electrical contact resistance are evaluated to investigate the morphology of the worn surfaces and the influence of Cu NPs on tribofilms.

Wear tests show that the addition of Cu NPs as lubricant additives could reduce wear and increase load-carrying capacity of commercially available lubricants remarkably, indicating that Cu NPs have a good compatibility with the existing lubricant additives in commercially available lubricants.

The tribological properties of Cu NPs as lubricant additives in three kinds of commercially available lubricants were investigated in this paper. These results are reliable and can be very helpful for application of Cu NPs as lubricant additives in industry.

The purpose of this paper is to synthesize oil-soluble copper (Cu) nanoparticles modified with free phosphorus and sulfur modifier and investigate its tribological properties as environment-friendly lubricating oil additives.

To improve the anti-oxidation properties of these nanoparticles, two kinds of surface modifiers, oleic acid and oleylamine were used simultaneously. The morphology, composition, structure and thermal properties of as-synthesized Cu nanoparticles were investigated by means of transmission electron microscopy, X-ray powder diffraction, Fourier transform infrared spectrometry and differential thermal and thermogravimetric analysis. The tribological properties of as-synthesized Cu nanoparticles as an additive in liquid paraffin were evaluated with a four-ball friction and wear tester.

It has been found that an as-synthesized Cu nanoparticle has a size of 2-5 nm and can be well dispersed in organic solvents. Tribological properties evaluation results show that as-synthesized Cu nanoparticles possess excellent anti-wear properties as an additive in liquid paraffin. The reason lies in that as-synthesized surface-capped Cu nanoparticles are able to deposit on sliding steel surface and form a low-shearing-strength protective layer thereon, showing promising application as an environmentally acceptable lubricating oil additive, owing to its free phosphorus and sulfur elements characteristics.

Oil-soluble surface-modified Cu nanoparticles without phosphorus and sulfur were synthesized and its tribological properties as lubricating oil additives were also investigated in this paper. These results could be very helpful for application of Cu nanoparticles as environment-friendly lubricating oil additives.

The purpose of this paper is synthesis of oil-soluble non-spherical nanoparticles modified with free phosphorus and sulphur modifier and investigation of their tribological properties as environment-friendly lubricating oil additives.

To study the effect of morphology of nanoparticles on their tribological properties, rice-like CuO nanoparticles were synthesized. To improve the solubility of CuO nanoparticles in organic media, the in-situ surface modification method was used to synthesize these products. The morphology, composition and structure of as-synthesized CuO nanoparticles were investigated by means of transmission electron microscopy, X-ray powder diffraction, thermogravimetric analysis and Fourier transform infrared spectrometry. The tribological properties of as-synthesized CuO nanoparticles as an additive in liquid paraffin (LP) were evaluated with a four-ball tribometer. The morphology and elemental composition of worn steel ball surfaces were analysed by X-ray photoelectron spectroscopy.

It has been found that as-synthesized CuO nanoparticles with rice-like morphology have an average size of 7 and 15 nm along the shorter axle and longer axle, respectively, and can be well-dispersed in LP. Tribological properties evaluation results show that as-synthesized CuO nanoparticles as additives in LP show good friction-reducing, anti-wear and load-carrying capacities, especially under a higher normal load.

Oil-soluble rice-like CuO nanoparticles without phosphorus and sulphur were synthesized and their tribological properties as lubricating oil additives were also investigated in this paper. These results could be very helpful for application of CuO nanoparticles as environment-friendly lubricating oil additives, owing to their free phosphorus and sulphur elements characteristics.

The purpose of the work is to verify the offered hypothesis and to evaluate the potential of the modern Russian entrepreneurship in economy’s informatization.

A specially developed proprietary method of evaluation of entrepreneurship’s potential in economy’s informatization and the level of its opening is used, which is created on the basis of the classical method of effectiveness evaluation. The information and analytical basis of studying the entrepreneurship’s potential in economy’s informatization is the materials of the report “The Global Information Technology Report 2016. Innovating in the Digital Economy”, prepared and presented by INSEAD, JOHNSON (Cornell University) and World Economic Forum. The offered proprietary method envisages evaluation of entrepreneurship’s potential in economy’s informatization and the level of its opening on the basis of statistical data according to four criteria: business and innovational environment, business ICT infrastructure, usage of new ICT in business, and economic consequences of using new ICT in business.

The author evaluates the entrepreneurship’s potential in economy’s informatization in modern Russia in 2016 and concludes that entrepreneurship’s potential in modern Russia is rather high, due to which high value of the index of information economy’s formation in Russia is achieved. That is, large entrepreneurship’s potential in economy’s informatization should be viewed as a precondition for information economy’s formation in modern Russia.

The author proves that entrepreneurship’s potential in economy’s informatization is an important component of the process of information economy’s formation in the economic system and can stimulate successful and quick implementation of this process or, quite on the contrary, slow down it rated, based on which it should be paid more attention.

Social manufacturing has emerged. It aims to integrate the manufacturing resources of micro- and small-scale manufacturing enterprises (MSMEs) and help MSMEs cope with the dynamic, service-oriented and personalized market demands. In social manufacturing, MSMEs cooperate with each other through manufacturing resource sharing. However, because MSMEs are distributed and decentralized, the efficiency of establishing reliable cooperation between MSMEs is relatively low. Therefore, this paper presents a blockchain-driven cyber-credit evaluation system (BCCES) to implement distributed cyber-credit evaluation. BCCES can provide reliable cyber-credit for distributed MSMEs without the trusted third party. This can improve the efficiency of establishing reliable cooperation among unauthentic MSMEs.

The paper proposes a BCCES to evaluate MSMEs' cyber-credit in decentralized environment. In BCCES, a cyber-credit evaluation model is proposed by improving set pair analysis (SPA) method, and cyber-credit smart contract and distributed consensus mechanism are designed according to the runtime logic of distributed cyber-credit evaluation.

The results confirmed that BCCES is feasible and effective to implement cyber-credit evaluation without the trusted third party. With the advantages of blockchain, BCCES can automatically realize cyber-credit evaluation through smart contract and distributed consensus. At the same time, BCCES can evaluate the real-time cyber-credit of MSMEs based on their latest service evaluation. In addition, we can design corresponding smart contracts according to actual requirements, which makes blockchain applicable to different distributed scenarios.

The paper combines blockchain and SPA to implement cyber-credit evaluation in social manufacturing and provides a new feasible idea for cyber-credit evaluation without the trusted third party. This can also provide MSMEs a reference of applying blockchain to other distributed scenarios through combining smart contract and different algorithms.

The influence of the number and arrangement of bolts on the tensile properties of bolted composite laminates was studied in the present study.

Based on the finite element model, the stiffness degradation method is used to simulate the damage evolution process for the failure of bolted composite laminates. Using ABAQUS finite element software combined with material failure criteria, the numerical calculation of the connection strength and failure mode of bolted composite laminates was carried out.

The results of the study show that the tensile strength of the composite laminates connected by three bolts is higher than that of the laminates connected by two bolts. And the arrangement of different bolts has a great influence on the failure strength of bolted laminates.

Bolted connection of composite laminates is a common problem in engineering practice. The effect of bolt arrangement and number on the strength of composite laminates is studied in this manuscript.

This paper is mainly concerned with studying the e‐manufacturing scheduling issue based on the bills of materials (BOM) flows of products. On the basis of e‐manufacturing philosophy, a genetic algorithm (GA)‐based scheduling model for physical e‐manufacturing cells is put forward. By means of building the mapping relationship and dynamic task association among physical e‐manufacturing cells, logic e‐manufacturing cells, e‐manufacturing systems and e‐manufacturing environment, high‐level scheduling issues can be transformed as an inductive procedure concerning the scheduling results to corresponding physical e‐manufacturing cells. As verification, finally, a case study is given to demonstrate the method mentioned above.

In an e‐manufacturing environment, the acquisition of real time quality data and information is paramount for distributed collaborative manufacturers to make quick and correct actions towards quality problems in a manufacturing process. This paper attempts to assist manufacturers in obtaining such data and information and further to make decisions regarding quality control.

In this paper, an online quality information system (OQIS) for quality control in an e‐manufacturing environment is presented. The common object request broker architecture standards and client‐server technologies are applied to obtain real time data and information whenever required at different locations. In addition, several modules, responsible for product design, process planning, quality control and data input, are developed within a coherent OQIS information model.

Preliminary results show advantages of the OQIS for companies to obtain real time quality data and information. It can also suggest possible improvements pertaining to quality control towards e‐manufacturing.

The proposed OQIS can be further developed to solve such issues as explanation of complex quality information and deployment costs in the enterprise. Further research should be directed to the evolution of OQIS.

The OQIS can provide consistent quality data and information, based on which manufacturers can make timely and correct decisions in solving quality problems in an e‐manufacturing environment.

Studies addressing barriers to implement lean production (LP) from the perspective of risk management (RM) have not been so usual in the literature. Re-interpreting barriers to lean as potential risks that should be avoided or mitigated, this paper aims to identify and categorise risks in the implementation of LP to propose a framework, which provides an overview of risks that negatively influence this process.

Through a systematic literature review exploring papers in the Web of Knowledge database, 69 papers were selected. A descriptive analysis was first carried out to identify the evolution in the number of papers, usual terminologies, research methods, analytic tools and the RM phases approached by each paper. After that, an in-depth study of the paper sample was conducted to find risk factors and categories.

The authors found a list of 61 risk factors. Then, considering the sources of the identified risk factors, six broad categories of risks were defined, namely, top management risks, human resources risks, lean knowledge risks, technical risks, supply chain risks and cultural risks. The authors also defined 34 subcategories, resulting in a risk classification framework.

Based on the review, the authors identified literature gaps and provided a research agenda. A noteworthy research limitation is that the authors only selected papers about LP, so the authors might have missed some potential risks in lean implementation that may arise from other-related areas. Thus, the exploration of lean risks adopting other perspectives may constitute a promising pathway for further research.

The classification framework may help practitioners and researchers in risk identification, evaluation and mitigation. It can also enable the creation of response plans to risks in lean production implementation, as it indicates the potential risks that may be faced along with this process.

This study contributed to add the perspective of RM to the literature on lean implementation. The introduction of RM concepts and tools may generate more robust models of lean implementation. Therefore, the classification framework may represent a starting point to produce new knowledge about this research topic.

The optimal payment in the whole operation and maintenance period of water environment treatment PPP projects has become the main approach to realize sustainable development of projects. This study is aimed at constructing an effective payment model for the whole life period of projects to achieve win-win among all stakeholders, so as to provide a theoretical reference and managerial implications for the public sector in the whole operation and maintenance period.

In the whole operation and maintenance period of water environment treatment PPP projects, this article investigates how the public sector optimizes the payment in the whole operation and maintenance period of projects. Firstly, the projects' whole operation and maintenance period is divided into several stages according to the performance appraisal period. And then, the multi-stage dynamic programming model is constructed to design the payment construct model for the public sector in each performance appraisal stage. The payment from the public sector is the decision variable, and the deduction from the private sector is a random variable.

The optimal payment model showed that the relatively less objective weight of public sector leaded to its relatively more total payment and vice versa. Therefore, the sustainable development of the projects can only be ensured when the objective weights both of them should be balanced. Additionally, the deduction from the performance appraisal of private sector plays an important role in the model construction. The larger deduction the private sector undertakes, the smaller profits private sector has. Since the deduction at each stage is a random variable, the deduction varies with the different probability distributions obeyed by the practical deduction in each stage.

The findings from this study have provided theoretical and application references, and some managerial implications are also given. First, the improvement of the pricing system of public sector should be accelerated. Second, the reasonable profit of the private sector must be guaranteed. While pursuing the maximization of social benefits, the public sector should make full use of the price sharing mechanism in the market and supervise the real income situation of the private sector. Third is increasing the public to participate in pricing. Additionally, it is a limitation that the deduction is assumed to conform to a uniform distribution in this study. Other probability distributions on deduction can be essentially further sought, so as to be more line with the actual situation of the projects.

The optimal payment in whole operation and maintenance period of the projects has become an important issue, which is a key to project success. This study constructs a multi-stage dynamic programming model to optimize payment in the whole period of projects. Additionally, this study adds its value through deeply developing the new theories of optimal payment to more suitable for the practical problems, so that to optimize the design of payment mechanism. Meanwhile, a valuable reference for public and private sectors is provided to ensure the sustainable development of the projects.