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Currently, lubrication analysis of piston ring is generally done under engine rated operating condition. However, the engine (such as the vehicle engine) does not always operate in rated operating condition, and its operating condition changes frequently in actual use. In addition, the lubrication status of piston ring is generally assumed as the flooded lubrication or a certain form of poor lubrication in most of the lubrication analysis.

In this paper, based on the equations about the flow rate of lubricating oil and the variation of control volume, the flow model of lubricating oil in the piston ring-cylinder liner conjunction is established. The lubrication analysis of piston ring for a four-stroke engine under different engine operating conditions is done, in which the lubricating oil at the inlet of piston ring is considered as the lubricating oil attached on the relevant location of cylinder wall after the piston ring moves over at the previous stroke.

There is remarkable difference for the lubrication characteristics of the piston ring under different engine operating conditions. The worst lubrication status of piston ring may not take place under engine rated operating condition.

In this paper, based on the measured engine cylinder pressure, the lubrication analysis of piston ring for a four-stroke engine under different engine operating conditions is done in which the lubricating oil supply condition at the inlet of piston ring is considered. The results of this paper are helpful for the design and research of engine piston ring-cylinder liner conjunction.

Current lubrication analyses of misaligned journal bearings were generally performed under some given preconditions. To make the lubrication analysis closer to the actual situation and usable to the journal bearing design, the purpose of this paper was to calculate the lubrication characteristics of misaligned journal bearings considering the viscosity-pressure effect of the oil, the surface roughness and the elastic deformation of the journal bearing at the same time.

The lubrication of bearings was analyzed using the average Reynolds equation. The deformation of the bearing surface under oil film pressure was calculated by a compliance matrix method. The compliance matrix was established by finite element analysis of the bearing housing. The viscosity-pressure and viscosity–temperature equations were used in the analysis.

The oil viscosity-pressure relationship has a significant effect on the lubrication of misaligned journal bearings. The surface roughness will affect the lubrication of misaligned journal bearings when the eccentricity ratio and angle of journal misalignment are all large. The directional parameter of the surface has an obvious effect on the lubrication of misaligned journal bearings. The deformation of the bearing surface has a remarkable effect on the lubrication of misaligned journal bearings.

The lubrication characteristics of misaligned journal bearings were calculated considering the viscosity-pressure effect of the oil, the surface roughness and the elastic deformation of the journal bearing at the same time. The results of this paper are helpful to the design of the bearing.

Current lubrication analyses of misaligned journal bearings are generally performed under some given preconditions. The purpose of this paper is to calculate the lubrication characteristics of a journal bearing with journal misalignment caused by shaft deformation under load, considering the surface roughness, thermal effect and (thermal and elastic) deformation of bearing surface simultaneously.

The lubrication of bearing was analyzed by average flow model based generalized Reynolds equation. The deformation of bearing surface under pressure or heat of oil film was calculated by compliance matrix method. The compliance matrix was established by finite element analysis. The temperature distributions of oil film and bearing were calculated by energy equation and heat conduction equation.

When the thermal deformation of bearing and journal surface is considered, the radius clearance affects not only the value of the maximum oil film pressure and minimum oil film thickness, but also the distribution of oil film pressure and thickness of misaligned bearing. The effect of thermal deformation of bearing on the performance of misaligned bearing is larger than that of elastic deformation of bearing. Whether or not the surface roughness affects the performance of misaligned bearing and the affecting level depends greatly on the condition of deformation of bearing surface.

The surface roughness, thermal effect and (thermal and elastic) deformation of bearing surface were considered simultaneously in the thermoelastohydrodynamic lubrication analysis of bearing with journal misalignment caused by shaft deformation under load. The results of this paper are helpful to the design of the bearing.

This paper aims to examine the relationships between the group affiliates’ dual legitimacy (membership legitimacy and societal legitimacy) and dual resource acquisition (intra-group and out-group), and the moderating roles of environmental uncertainty and munificence in the emerging economies.

This paper adopts hierarchical regression analysis to test the hypotheses based on the unique data of 251 group affiliated firms in China and applies the alternative measurements and alternative methodology of structural equation modeling into robustness check to confirm the results.

The results show as follows: the group affiliates can benefit from membership legitimacy for intra-group resource acquisition and out-group resource acquisition through the mediations of societal legitimacy and intra-group resource acquisition. However, in the linkage between affiliates’ membership legitimacy and intra-group resource acquisition and the linkage between societal legitimacy and out-group resource acquisition, environmental uncertainty plays the positive moderating roles while environmental munificence plays the negative moderating roles. Under the condition of high environmental uncertainty and low environmental munificence, the linkage between membership legitimacy and intra-group resource acquisition, and the linkage between societal legitimacy and out-group resource acquisition reach the strongest level.

The findings highlight the importance of dual legitimacy building for group affiliates to acquire resources both inside and outside the business group when they operate in emerging economies characterized by high environmental uncertainty and low environmental munificence. However, it does not explore the contextual factors (e.g. institutional distance) affecting the relationship between the affiliate’s membership legitimacy and societal legitimacy. Then more group-level factors are expected to be included and explored with multi-level models in the future studies.

The findings reveal the mechanism of how group affiliates benefiting differently from dual legitimacy to acquire resources in the emerging economies, which also provide a new interpretation for the questions of who benefiting more from the group affiliation, how and why (Carney et al., 2009). This research also explores the moderating roles of task environmental characteristics (environmental uncertainty and environmental munificence) on the affiliate's dual legitimacy and dual resource acquisition, which helps understand why legitimacy building is more important in terms of resource acquisition in the emerging economy characterized by uncertainty and non-munificence.

This study aims to elaborate on how firms manage research and development (R&D) activities by examining the relationship between ownership concentration and corporate R&D investment, as well as the moderating role of stock options in this relationship.

The study sample comprised 354 Chinese listed firms from 2011 to 2019, and the Tobit model and the system GMM test are used to check robustness.

The results reveal that ownership concentration and R&D investment have an inverted U-shaped relationship. In the presence of stock options, this inverted U-shaped relationship is significantly weaker.

The results have important managerial implications for firms that aim to grant stock options and improve the impact of ownership concentration on R&D investment strategies.

The problem of port and starboard ambiguity will exist when only utilize the vector or scalar parameters. Meanwhile, the amplitude-phase error between the vector and scalar can also cause this problem. In this paper, a compound MEMS vector hydrophone which contains cilia vector microstructure and piezoelectric ceramic tube has been presented to solve the problem. Compared with traditional MEMS vector hydrophone, the compound MEMS vector hydrophone can realize the measurement of sound pressure and vibration velocity simultaneously.

A compound MEMS vector hydrophone has been presented. The unipolar directivity of the combined signal which combine the acoustic pressure and vibration velocity is used to achieve the direction of arrival (DOA). This paper introduced the working principle and the target detection mechanism of the compound vector hydrophone. The amplitude and phase error are analyzed and corrected in the standing wave tube. After that, the authors use beam-forming algorithm to estimate the DOA.

The experimental results in the standing wave tube and the external field verified the vector hydrophone's directional accuracy up to 1 and 5 degrees, respectively.

The research of compound vector hydrophone plays an important role in marine acoustic exploration and engineering applications.

This research provides a basis for MEMS hydrophone directivity theory. The compound vector hydrophone has been applied in the underwater location, with a huge market potential in underwater detection systems.

The study examines how process/organizational innovation and R&D spending mediate the relationship between financial performance and the resource dependence theory in Fintech, providing insights into effective innovation strategies for achieving sustainable financial performance.

Data from 191 financial firms in Taiwan was collected from annual reports using the Taiwan Economic Journal (TEJ), a financial information provider. Content analysis was used to measure innovation activities and financial performance, with process and organizational innovation defined. R&D expenditures were also collected and used in statistical analysis to explore the relationship between variables.

This study on the financial services industry shows that process innovation and R&D expenditure positively impact firm performance, while organizational innovation may have a negative short-term effect but could have long-term benefits.

Limitations of this study include vulnerability to spurious effects and the use of data from only listed financial service firms. Future research should use more short-term performance data and include unlisted firms in the financial services industry to extend the study’s coverage.

This study extends resource dependence theory to financial services and explores the effects of process and organizational innovation on firm performance. Results show that internal process management boosts performance, while external collaboration with startups enhances Fintech innovation and efficiency, with positive short-term effects. The study highlights the importance of interacting with external organizations to access resources and improve performance in financial services.

There is an increasing popularity for the continuum robot in minimally invasive surgery owing to its compliance and dexterity. However, the dexterity takes the challenges in loading and precise control because of the absence of the shape tracking for the continuum robot. The purpose of this paper is to propose a new type of continuum manipulator with variable stiffness that can track the bending shape timely.

The low-melting-point alloy (LMPA) is used to implement the stiffness variation and shape detection for the continuum manipulator. A conceptual design for a single module is presented, and the principle of stiffness control based on the established static model is formulated. Afterward, a shape detection method is introduced in which the shape of the continuum manipulator can be detected by measuring the resistance of every LMPA. Finally, the effect of the proposed variable stiffness method is verified by simulation; the variable stiffness and shape detection methods are evaluated by experiments.

The results from the simulations and experiments indicate that the designed continuum manipulator has the ability of stiffness variation over 42.3% and the shape detection method has high precision.

Compared with conventional structures, the novel manipulator has a simpler structure and integrates the stiffness variation and shape detection capabilities with the LMPA. The proposed method is promising, and it can be conveniently extended to other continuum manipulators.

While previous research has demonstrated the positive effects of digital business strategies on operational efficiency, financial performance and value creation, little is known about how such strategies influence innovation performance. To address the gap, this paper aims to investigate the impact of a firm’s digital business strategy on its innovation performance.

Drawing on the dynamic capability view, this study examines the mechanism through which a digital business strategy affects innovation performance. Data were collected from 215 firms in China and analyzed using multiple regression and structural equation modeling.

The empirical analysis reveals that a firm’s digital business strategy has positive impacts on both product and process innovation performance. These impacts are partially mediated by knowledge-based dynamic capability. Additionally, a firm’s digital business strategy interacts positively with its entrepreneurial orientation in facilitating knowledge-based dynamic capability. Moreover, market turbulence enhances the strength of this interaction effect. Therefore, entrepreneurial-oriented firms operating in turbulent markets can benefit more from digital business strategies to enhance their knowledge-based dynamic capabilities and consequently improve their innovation performance.

This study contributes to the understanding of how a firm’s digital business strategy interacts with entrepreneurial orientation in turbulent markets to shape knowledge-based dynamic capability, which in turn enhances the firm’s innovation performance.