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At present, one of the key equipment in pillar industries is a large rotating machinery. Conducting regular health monitoring is important for ensuring safe operation of the large rotating machinery. Because vibrations sensors play an important role in the workings of the rotating machinery, measuring its vibration signal is an important task in health monitoring. This paper aims to present these.

In this work, the contact vibration sensor and the non-contact vibration sensor have been discussed. These sensors consist of two types: the electric vibration sensor and the optical fiber vibration sensor. Their applications in the large rotating machinery for the purpose of health monitoring are summarized, and their advantages and disadvantages are also presented.

Compared with the electric vibration sensor, the optical fiber vibration sensor of large rotating machinery has unique advantages in health monitoring, such as provision of immunity against electromagnetic interference, requirement of less insulation and provision of long-distance signal transmission.

Both contact vibration sensor and non-contact vibration sensor have been discussed. Among them, the electric vibration sensor and the optical fiber vibration sensor are compared. Future research direction of the vibration sensors is presented.

The purpose of this paper is to study heat and steam transfer in a vertical air gap and improve thermal protective performance of protective clothing under thermal radiation and hot steam.

An experiment-based model was introduced to analyze heat and moisture transfer in the vertical air gap between the protective clothing and human body. A developed test apparatus was used to simulate different air gap sizes (3, 6, 9, 12, 15, 18, 21 and 24 mm). The protective clothing with different air gap sizes was subjected to dry and wet heat exposures.

The increase of the air gap size reduced the heat and moisture transfer from the protective clothing to the skin surface under both heat exposures. The minimum air gap size for the initiation of natural convection in the dry heat exposure was between 6 and 9 mm, while the air gap size for the occurrence of natural convection was increased in the wet heat exposure. In addition, the steam mass flux presented a sharp decrease with the rising of the air gap size, followed by a stable state, mainly depending on the molecular diffusion and the convection mass transfer.

This research provides a better understanding of the optimum air gap under the protective clothing, which contributes to the design of optimum air gap size that provided higher thermal protection against dry and wet heat exposures.

This study investigates the impact of board gender diversity and foreign ownership on innovation in Chinese firms.

The authors use data for Chinese manufacturing firms listed on the Shanghai and Shenzhen stock exchanges, for a sample over the period 2008–2017. Ordinary least square (OLS) is used as the baseline methodology, with cluster OLS, two-stage Heckman test, Blau index and Shannon index used to address endogeneity issues.

The results show that gender diversity on the board has a positive effect on corporate innovation as measured by the total number of patent applications, invention patent applications, utility model patent applications and design patent applications. Our findings also provide support for the critical mass participation of female directors on the board being associated with more innovation. They also reveal that innovation output does not vary across state-owned enterprises (SOEs) and non-SOEs. These outcomes reveal that SOEs' advantages, such as easy access to funding and more support of government, are likely offset by their disadvantages, such as different goals and having more agency issues. Because of intense political power and networks in Chinese firms, qualified foreign institutional investors (QFIIs) are less motivated to enhance innovation activities.

This study highlights the role of board gender diversity in enhancing innovation among Chinese manufacturing firms. Our findings provide support for regulatory bodies' role regarding women's participation on the board.

This research adds to literature by addressing the largely ignored questions of whether providing a gender-diverse board enhances innovation, whether critical mass participation has a greater effect on improving firm innovation and whether the influence of women directors varies with ownership structure.

This paper aims to investigate the lubrication performance of cam/tappet contact during start up. Especially, the thermal insulation effects of coating on the lubrication performance during cold start up process and warm start up process are studied.

A numerical model for the analysis of thermal elastohydrodynamic lubrication of coated cam/tappet contact is presented. In this model, the Reynolds equation and the energy equations are discretized by the finite difference method and solved jointly.

During start up, the contact force at cam nose-to-tappet contact decreases with increasing time, while the absolute entrainment velocity has the upward trend. The minimum film thickness, maximum average temperature and friction power loss increase with increasing time, while the coefficient of friction decreases during start up. Because of the thermal insulation effect, the coating can significantly increase the degree of temperature rise. Compared with the uncoated case, the coated cam/tappet results in a lower friction power loss. Generally, the friction power loss in the cold start up process is much higher than that in the warm start up process.

By this study, the lubrication performance and the kinematics and the dynamics of the cam/tappet during start up process are investigated. Meanwhile, the thermal insulation effect of coating is also illustrated. The difference of lubrication performance between cold start up process and warm start up process is analyzed. The results and thermal elastohydrodynamic lubrication method presented in this study can be a guidance in the design of the coated cam/tappet.

The purpose of this research is to examine whether board gender diversity reduces the agency costs of firms in the context of Chinese listed firms.

This paper uses a large sample of 23,340 firm-year observations of Chinese listed companies during 2004–2017. The authors use ordinary least squares regressions as the primary methodology with a wide range of methods to control for endogeneity and to check robustness, including the fixed-effect method, instrumental variable approach, lagged gender diversity measures, propensity score matching, Blau index, Shannon index and industry-adjusted measures of agency costs.

The evidence reveals that the participation of female directors in corporate board reduces agency costs, which correlates with conflicts of interest. Moreover, gender-diverse boards are more effective in state-owned enterprises (SOEs), in which agency issues are more severe. Female directors also provide better monitoring roles in more-developed areas. Finally, corporate boards that have a critical mass of female directors have a greater tendency to reduce agency costs as compared to their token participation. Overall, all findings support the validity of agency theory.

This study shows the economic benefit of female directors in the boardroom by reducing agency costs and by improving firms' governance structure. Regarding the government, which is gradually introducing board gender diversity policies, this study provides valuable pragmatic information for Chinese regulators on this issue.

This study extends the literature by providing evidence that gender diversity in boardroom matters for shareholders' wealth maximization. It provides novel evidence that a critical mass of female directors is more effective in reducing agency costs compared to a single female on the board, and that the effect of gender diversity varies in relation to ownership structure and region.

The purpose of this paper is to explore an application of computer‐aided design and manufacture (CAD/CAM) to a process of electronically surveying a scanned dental cast as a prior stage to producing a sacrificial pattern for a removable partial denture (RPD) metal alloy framework.

With the introduction of laser scan technology and commercial reverse engineering software, a standard plaster maxillary dental cast with dentition defect was successfully scanned and created as a STL‐formatted digital cast. With the software, the unwanted undercuts were eliminated based on the desired path of insertion. Parts of the RPD framework were then successfully custom‐designed and combined as a whole.

A sacrificial pattern was produced by rapid prototyping (RP) method and finally casted with chromium cobalt alloy. With suitable finishing process, both the sacrificial pattern and the casted framework fitted the cast well.

The research indicated the feasibility of creating a library of RPD framework components. It is believed that, in the future, with the advance of the techniques, a totally new platform can be developed for the design and fabrication of custom‐fit RPD framework based on the CAD/CAM/RP system.

This research posits that e-vendors can use product aesthetic information (PAI) as a strategic positing tool to shape consumers’ perceptions of e-vendors’ websites.

To test this framework, variations on a garment’s color (a crucial element of product aesthetics) are presented to four different treatment groups to determine whether aesthetic treatment influences the perception of the website.

The results suggest that consumers who consider a product visually appealing also perceive the e-vendor’s website as useful, resulting in enjoyment of the shopping experience. Positive perceptions lead consumers to form positive attitudes toward the vendor’s website.

While product aesthetics is well-studied in marketing and psychology, its relevance to the e-commerce domain is relatively underexplored. To fill the void, the paper proposes a theoretical framework that explains how PAI influences buyers’ cognitive and affective evaluations of their online shopping experiences, which in turn shapes their attitudes toward e-vendors’ sites.

The contact and lubrication performances, which were previously estimated assuming a Gaussian surface, are insufficient due to the non-Gaussian surface characteristics of the honing liner. The purpose of this study is to analyze the liner honing surface and examine its effects on the contact and flow performance.

The fast Fourier transform (FFT) method was used to generate the liner honing texture. Subsequently, an elastoplastic contact model based on boundary element theory was constructed and simulated for the honing surface. The results were compared with those obtained using a Gaussian surface. In addition, flow factors of the honing surfaces were also compared.

The contact pressure and flow factors demonstrate significant disparities when dealing with non-Gaussian surfaces. In the deterministic model, the pressure exhibits considerably diminished magnitudes and a more evenly distribution. Moreover, when the gap between surfaces is narrow, the discrepancy in flow factor across different directions on the real honing surface becomes more prominent compared with the Gaussian surface.

The model incorporates the influence of the non-Gaussian honing surface, thereby enabling more accurate prediction.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2023-0198/

Friction and wear are very important factors in predicting the performance of journal bearings, particularly under heavy load in start-up processes. However, there are few relevant studies on the numerical model. This study aims to establish a transient-mixed lubrication model to predict the performance of journal bearings, focusing on the friction and wear behavior under heavy load during start-up.

The average Reynold equation, three-dimensional energy equation, shear stress model for friction and Archard model for wear are coupled in the transient model by finite difference method. The linear wear simulation method is bought out to reduce the update times and the calculation time.

The different start-up accelerations and linear wear times set are compared and discussed, which indicates a reasonable start-up acceleration is necessary for journal bearings under heavy load during start-up, and setting linear wear times is an effective method to reduce the simulation time significantly. Furthermore, the wear profile in the start-up process spreads in both the clearance and circumferential directions, but mainly in the clearance direction, which increases the minimum film thickness and affects the friction performance.

This study is of great significance for the numerical prediction of the transient performance of journal bearings during start-up considering friction and wear.

The purpose of this research is to investigate how the consumer’s trusting mechanism influences their behavioral adoption intention in the context of genetic testing.

Based on the technology acceptance theory and trust formation theory, the research posits and develops a comprehensive trust model by integrating trust-related factors that correlate to the consumer’s trusting beliefs and trusting intention. Survey data with 525 respondents allow to test and validate the model.

The tested model shows that technology institutional trust base, end-user’s cognitive trust base and social influence are significant determinants of trusting beliefs. The findings also reveal that mediation effects of performance expectancy and perceived risks exist in the relationship between trusting beliefs and trusting intention.

The foreseeable positive impact and rapid market growth of emerging healthcare technologies necessitate the strong need to study user acceptance. However, there is a lack of research on how consumers trust and their adoption intention of such innovations. Prior empirical evidence from different contexts and perspectives also show contradictory findings. This research extends the existing technology acceptance literature to a healthcare context, provides an improved generalized understanding of the consumer’s trusting mechanism in emerging biotechnology and discusses practical insights for regulatory authorities, healthcare institutes and medical professionals.