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At the present time, green cutting has become the focus of attention in ecological and environmental protection. Water vapor is cheap, pollution‐free and eco‐friendly. Therefore, it is a good and economical coolant and lubricant. To find the discipline of nozzle diameter, the parameters of water vapor jet flow and cooling distance influence on its lubricating action effect, experiments were carried out in which YT15 (P10 type in ISO) tool was used in cutting C45 steel.

The vapor generator and vapor feed system are manufactured. The temperature and velocity distribution of water vapor jet flow influences the velocity such that water vapor fills up the capillaries and forms the boundary lubricating film layer in the cutting zone, and the temperature and velocity distribution of the vapor jet flow section contains the effective area for the lubricating effect. Through the temperature distribution measured, the empirical formula of temperature distribution is obtained and simulated by Matlab. The turning experiment was carried out according to quantity in cutting υ_c=45, 60, 75, 90, 105, 120 mm/min, f=0.1 ∼ 0.3 mm/rev, a_p=1, 2, 3, 3.5 mm and the jet flow parameters were changed, respectively.

It was found that: significant decrease of cutting force can be realized with reduced nozzle diameter, increased the sett pressure and shortened the cooling distance. However, reduced to a certain extent it will lead to the increase of the cutting force. The optimal nozzle diameter is 2 mm for the best lubricating effect. The effect on cutting force of the cooling distance is much better than the setting pressure. Significant decrease of friction coefficient of tool‐chip can be realized with reduced nozzle diameter. However, reduced to a certain extent it will lead to the increase of friction coefficient. Significant thinness of chips can be realized by reducing nozzle diameter. But if the diameter is reduced to a certain degree, chips will be thickened. Increased set pressure and shortened cooling distance can both reduce chip thickness, resulting in reduction of chip deformation coefficient. Since water vapor has the advantage of being cheap, pollution‐free and harmless, and there is no need for disposal and recycling, it is ideal for cooling and lubricating technology in green cutting.

The paper establishes the discipline of nozzle diameter, the parameters of water vapor jet flow and cooling distance influence on its lubricating action effect.

Green machining is becoming increasingly more popular due to concern regarding the safety of the environment and human health. The important implementation of stricter Environmental Protection Agency regulations associated with the use of ample amount of coolants and lubricants has led to this study on a new green machining technology with application of water vapor as coolants and lubricants in cutting Ni‐based superalloys and titanium alloy Ti‐6Al‐4V with uncoated carbide inserts (ISO Type K10). The purpose of this paper is to show that machining technology with application of water vapour could be an economical and environmentally compatible lubrication technique for machining difficult‐cut‐materials.

In this paper, the effect of water vapor applications in machining difficult‐cut‐materials have been investigated in detail, the cutting force, the chip deformation coefficient, the rake face wear and the width of tool flank land VB have been examined and analyzed, and a new green cutting technology is researched to machining Ni base superalloys and Ti‐6Al‐4V difficult‐cut‐materials.

The cutting force of machining Ni base superalloys and Ti‐6Al‐4V was affected by direct water vapor application, being lower than dry cutting and wet machining for all machining conditions; the Λh is the smallest with applications of water vapor as coolants and lubricants compared to dry cutting, pure water and oil water emulsion conditions the tool life extended by about six times than dry cutting, about four times than oil water emulsions at low cutting speed (ν_c<100 m/min), and about two‐four times than dry cutting, about two‐three time than oil water emulsions at higher cutting speed (ν_c>100 m/min) during machining Ti‐6Al‐4V with application of water vapor direct into the cutting zone.

The green cutting technology which applies water vapor as coolants and lubricants advocates a new method for machining difficult‐cut‐materials (Ni base superalloys and Ti‐6Al‐4V) without any environment pollution and operator health problem because the cutting force and chip deformation coefficient are reduced, the tool life is extended, and the tool flank wear can be decreased with applications of water vapor as coolants and lubricants to alleviate the adhering and diffusion wear compared to wet cutting and dry cutting.

Nowadays, green cutting has become the focus because of its ecological problem and the necessary environment protection, so that the research on experimentation of green cutting with water vapor as coolant and lubricant is studied because water vapor has many benefits of cheapness, no pollution, no harm and no recycling and handling.

The vapor generator and the vapor feed system are manufactured, the distribution of temperature and velocity of vapor jet flow are simulated by MATLAB program, and under the conditions of compress air, oil water emulsion, water vapor as coolant and lubricant and dry cutting, respectively, the turning experimentation of comparison which the tool is YT15, and the working material is steel 45.

Water vapor, as coolant and lubricant, the cutting force is reduced, respectively about 30‐40, 20‐30 and 10‐15 percent by comparing to dry cutting, compressed air and oil water emulsion. The cutting temperature is, respectively about 30, 40 and 50 percent with the other conditions of dry cutting, compressed air and oil water emulsion. The friction coefficient and the chip deformation coefficient are correspondingly decreased and the surface roughness value has been diminished too. Through analysis of the experimental results, water vapor as coolant and lubricant possesses better lubricating action because of the excellent penetration performance and the low lubrication layer shearing strength of water vapor.

Water vapor as coolant and lubricant provides a novel method for realizing no contamination green cutting.

This paper aims to anticipate the possible development direction of WAAM. For large-scale and complex components, the material loss and cycle time of wire arc additive manufacturing (WAAM) are lower than those of conventional manufacturing. However, the high-precision WAAM currently requires longer cycle times for correcting dimensional errors. Therefore, new technologies need to be developed to achieve high-precision and high-efficiency WAAM.

This paper analyses the innovations in high-precision WAAM in the past five years from a mechanistic point of view.

Controlling heat to improve precision is an effective method. Methods of heat control include reducing the amount of heat entering the deposited interlayer or transferring the accumulated heat out of the interlayer in time. Based on this, an effective and highly precise WAAM is achievable in combination with multi-scale sensors and a complete expert system.

Therefore, a development direction for intelligent WAAM is proposed. Using the optimised process parameters based on machine learning, adjusting the parameters according to the sensors’ in-process feedback, achieving heat control and high precision manufacturing.

With the rapid increase in the number of installed wind turbines (WTs) worldwide, requirements and expenses of maintenance have also increased significantly. The condition monitoring (CM) of WT provides a strong “soft guarantee” for preventive maintenance. The supervisory control and data acquisition (SCADA) system records a huge amount of condition data, which has become an effective means of CM. The main objective of the present study is to summarize the application of SCADA data to fault detection in wind turbines, analyze its advantages and disadvantages and predict the potential of future investigations on the use of SCADA data for fault detection.

The authors first review the means of WT CM and summarize the characteristics of CM based on SCADA data. To ensure the quality of SCADA data, data preprocessing methods are analyzed and compared. Then, the failure modes of the key components are discussed and the SCADA data used for fault detection of each component are compared. Moreover, the fault detection methods for WT are classified and a general framework for fault detection is proposed. Finally, the issues in the WT fault detection method based on SCADA data are reviewed.

Based on the performed analyses, it is found that although the fault detection accuracy based on SCADA data is relatively poor, it has low capital expenses and low computational cost. More specifically, when there is scarce fault data, the normal SCADA data can be used to detect the fault time. However, the specific fault type cannot be identified in this way. When a large amount of fault data are accumulated in the SCADA system, it can not only detect the occurrence time of the fault but also identify the specific fault type.

The main contribution of the present study is to summarize the pre-processing methods for SCADA data, the data required for fault detection of key components and the characteristics of the fault detection model. Then we propose a general fault detection framework for wind turbines based on SCADA data, where the maintenance workers can choose the appropriate fault detection method according to different fault detection requirements and data resources. This article is expected to provide guidance for fault detection based on time-series sensor signals and be of interest to researchers, maintenance workers and managers.

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.

This study aims to examine the relationship between board capital and firm performance in the Chinese tourism industry.

The study’s sample includes firms from the Chinese hotel, air transportation/travel and catering industries. This study explores the governance environment in tourism industries. This study estimates three dimensions of the board, including education, expertise and directors interlock. These dimensions are further grouped as human capital (i.e. education and expertise), social capital (interlocks) and board capital (sum of social and human capital). Ordinary least square regressions with multiple robustness tests are used to investigate the effect of board capital on firm value in Chinese listed tourism firms during 2005–2018.

This study finds that board capital positively impacts firm performance in its dimensions of human and social capital. This study also highlights the two important ownership contexts, namely, institutional investors and state-ownership, that shape the board capital-firm performance association in the Chinese tourism industry.

The findings suggest that board capital plays a significant role in corporate decisions. The results illustrate that higher board capital improves both governance mechanisms and resource provision roles of the board, resulting in higher firm value. The results further offer implications for managers and shareholders of tourism firms when electing directors as shareholders’ representatives.

The study has two important contributions. First, it extends the prior literature of firm value by considering the board’s human and social dimensions in the tourism sector. Second, contrary to prior research on board, this study takes three facets of board capital, education, expertise and interlocks that improve governance mechanisms and bring new resources in the shape of skills, knowledge and expertise.

This study aims to explore the impact of the chief executive officer’s (CEO) age on adopting global reporting initiative (GRI) framework for corporate social responsibility (CSR) reporting. It also underlines how board social capital moderates the relationship between CEO age and the adoption of the GRI framework.

Chinese A-listed companies during 2010–2018 were used. The authors applied a logistic regression model due to the binary nature of the dependent variable. For robustness, two-step generalized method of moments (GMM) and lagged independent variables are used.

The study finds that CEO age negatively impacts the firm’s choice of GRI reporting framework. The social capital of the board positively moderates this relationship. This finding is based on the notion that as a CEO grows older or headed toward retirement age, his/her interest in CSR diminishes due to a shorter career horizon. Boards with external links provide better advice on CSR issues and mitigate the negative impact of CEO age.

The study results are important for understanding the GRI framework’s development and implementation, particularly in China.

To the best of the authors’ knowledge, this is the first study that deeply examines how CEO age affects GRI adoption in the Chinese context and how the board’s social capital moderates this relationship.

The purpose of this paper is to study the mechanical and corrosion behaviors of selective laser melting (SLM) 30CrMnSiA steel.

The microstructure, mechanical behavior and corrosion resistance of SLM 30CrMnSiA steel were studied by electrochemical test and immersion experiment.

The results showed that the microstructure of SLM 30CrMnSiA steel contained equiaxed fine (25.0 µm) ferrite and lamellar pearlite. The tensile strength of SLM 30CrMnSiA steel under the process parameters is 1,447 MPa and the elongation is 7.5%. As the immersion/salt spray test time increased to 15 days/48 h, corrosion mainly occurred in the local position of the sample and corrosion resistance decreased. When the immersion/salt spray test time increased to 30 days/168 h, the corrosion production covered the surface of the samples and the corrosion resistance increased.

The paper can guide the application and in situ repair for low-alloy steel by additive manufacturing.

This study intends to review studies on the success criteria and critical success factors (CSFs) for mega infrastructure construction projects (MICPs) from journal articles between 2000 and 2018 to (1) identify the publication trend of success criteria and CSFs for MICPs; (2) explore distributions of selected papers, including the distribution of journals, authors’ origin/country and publications by country or region focus; and (3) summarize the findings of success criteria and CSFs studies of MICPs.

A methodical and systematic analysis of 38 selected journal articles was conducted using descriptive analysis to obtain the annual trend of publications, distributions of publication sources, contributors’ origin/country, regions/countries of research focus, methods involved in publications and thematic analysis to identify and categorize success criteria and CSFs for MICPs.

Australia, the USA, UK, China and Hong Kong had been the leading contributors for publications on success criteria and CSFs for MICPs; meanwhile, China, Australia and the UK have been the countries of focus for most studies on this specific topic. This review identified 20 success criteria grouped into 5 constructs and 36 CSFs grouped into 5 categories and, respectively, integrated them into two conceptual frameworks. The top five CSFs were adequate resource availability, partnering/relationships with key stakeholders, adequate communication and coordination among related parties, public support or acceptance and clear strategic vision. Three implications, namely, evaluation indicators, relationships between CSFs and the success of MICPs and human-related factors, are highlighted in future research.

The identified success criteria and CSFs provide a basis for evaluating the success possibility of MICPs and serve to identify areas for further improvement. Additionally, the CSFs checklist and framework have been established, which could help to conduct further empirical studies. Finally, the holistic analysis identifies gaps in the body of knowledge, revealing avenues for future research.