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The purpose of this paper is to explore the effect of ZnO on the structure and properties of micro-arc oxidation (MAO) coating on rare earth magnesium alloy under large concentration gradient.

The macroscopic and microscopic morphology, thickness, surface roughness, chemical composition and structure of the coating were characterized by different characterization methods. The corrosion resistance of the film was studied by electrochemical and scanning Kelvin probe force microscopy. The results show that the addition of ZnO can significantly improve the compactness and corrosion resistance of the MAO coating, but the high concentration of ZnO will cause microcracks, which will reduce the corrosion resistance to a certain extent.

When the concentration of zinc oxide is 8 g/L, the compactness and corrosion resistance of the coating are the best, and the thickness of the coating is positively correlated with the concentration of ZnO.

Too high concentration of ZnO reduces the performance of MAO coating.

The MAO coating prepared by adding ZnO has good corrosion resistance. Combined with organic coatings, it can be applied in corrosive marine environments, such as ship parts and hulls. To a certain extent, it can reduce the economic loss caused by corrosion.

The effect of ZnO on the corrosion resistance of MAO coating in electrolyte solution was studied systematically, and the conclusion was new to the common knowledge.

This study has dealt with the gap in the literature, by probing the influence of innovation capability on business performance. This paper aims to test the moderation role of technological turbulence (TT) and market turbulence (MT) on the relationship between innovation capability (IC) and business performance (BP).

The study used a quantitative survey and a sample size of 579 departmental heads. Branch managers and permanent staff from the Greater Accra, Ashanti and Western Region in the Ghana telecommunication sector. The obtained data was analysed through the STATA 15.0 and AMOS statistical software package.

The empirical results from multiple linear regressions revealed that product/service innovation, process innovation, marketing innovation and administrative innovation had positive effects on business performance. The outcome of the moderation analysis further shown that technological turbulence positively moderates the relationship that existed between the various constructs of innovation capability and business performance indicating that technological turbulence significantly strengthens the relationship between these variables. On the contrary, market turbulence significantly weakens the relationship between the various innovation capability constructs and business performance.

Although this research has made significant contributions to both theory and practice, there are certainly some limitations and future research directions that need to be considered to appropriately position the study findings. Firstly, because of the limited sample size (579), further testing of these constructs needs to be carried out in future research using alternative data. Related to this, it would be prudent if the instruments and models developed in this research were tested in different industry contexts. Also, because the Ghana telecommunication sector is made up of foreign companies, comparative research could be conducted to compare the IC and performance of Ghana and the other countries where these companies operate. Indeed, analyses of IC and BP associated with the same companies in different countries may prove to be very beneficial in the global context. Secondly, this research used only TT and MT to test the moderating effect of ET on the association of IC with BP. Future research can include competition intensity which may change or confirm the outcome of these studies. Thirdly, only qualitative data were used for the measurement of IC and the level of BP. Therefore, future research could use quantitative or both qualitative and quantitative data to confirm if there will be significant differences in the results obtained.

Literature has examined the moderation effect of ET on different variables and relationships in different organizational settings. This study has tried to analyse the moderating effect of ET on the relationship of IC with BP. The outcomes of this study are similar to the previous research studies mentioned above, however, limited studies have been conducted on IC and its relationship with BP in the context of ET especially in the most vibrant sector of Ghana’s economy. These findings are very innovative and contribute enormously to literature and knowledge by indicating which moderating ET positively and significantly strengthens and the type which weakens the existing relationship between IC and BP within the Ghanaian telecommunication sector which no researcher has conducted. These findings will go a long way by aiding the players in this sector to tauten their IC wings to achieve resilient performance around the globe.

This will also contribute to the growth of Ghana’s economy as sources of revenue and employment. Additionally, the results obtained from this study will prompt managers to make more informed and effective decisions regarding innovation activities and the environments in which they operate.

This paper adds knowledge and literature to the existing ones. It is a new development in the research field of Ghana. This is the first journal this study has been submitted.

The safety assessment of engineering structures under repeated variable dynamic loads such as seismic and wind loads can be considered as a dynamic shakedown problem. This paper aims to extend the stress compensation method (SCM) to perform lower bound dynamic shakedown analysis of engineering structures and a double-closed-loop iterative algorithm is proposed to solve the shakedown load.

The construction of the dynamic load vertexes is carried out to represent the loading domain of a structure under both dynamic and quasi-static load. The SCM is extended to perform lower bound dynamic shakedown analysis of engineering structures, which constructs the self-equilibrium stress field by a series of direct iteration computations. The self-equilibrium stress field is not only related to the amplitude of the repeated variable load but also related to its frequency. A novel double-closed-loop iterative algorithm is presented to calculate the dynamic shakedown load multiplier. The inner-loop iteration is to construct the self-equilibrated residual stress field based on the certain shakedown load multiplier. The outer-loop iteration is to update the dynamic shakedown load multiplier. With different combinations of dynamic load vertexes, a dynamic shakedown load domain could be obtained.

Three-dimensional examples are presented to verify the applicability and accuracy of the SCM in dynamic shakedown analysis. The example of cantilever beam under harmonic dynamic load with different frequency shows the validity of the dynamic load vertex construction method. The shakedown domain of the elbow structure varies with the frequency under the dynamic approach. When the frequency is around the resonance frequency of the structure, the area of shakedown domain would be significantly reduced.

In this study, the dynamical response of structure is treated as perfect elastoplastic. The current analysis does not account for effects such as large deformation, stochastic external load and nonlinear vibration conditions which will inevitably be encountered and affect the load capacity.

This study provides a direct method for the dynamical shakedown analysis of engineering structures under repeated variable dynamic load.

To explore the relationship between emergent user roles and perceived importance of user requirements in a social‐oriented community.

A field study was designed to uncover hidden online social networks, and to elicit and rate user requirements.

User roles might have an impact on their perceptions of requirements. The study showed that significant differences of perceptual requirements on regulation and links exist across user roles.

Only a small‐sized online community (approximately 300 members) participated in this study. One‐quarter of the population filled out the online survey.

Online community builders should invite a handful of different user roles to participate in the design and evolutionary processes of information systems.

The paper challenges popular views about the design of online communities.

A direct and unified approach is proposed toward simultaneously simulating large strain elastic behaviors of gellan gels with different gellan polymer concentrations. The purpose of this paper is to construct an elastic potential with certain parameters of direct physical meanings, based on well-designed invariants of Hencky’s logarithmic strain.

For each given value of the concentration, the values of the parameters incorporated may be determined in the sense of achieving accurate agreement with large strain uniaxial extension and compression data. By means of a new interpolating technique, each parameter as a function of the concentration is then obtained from a given set of parameter values for certain concentration values.

Then, the effects of gellan polymer concentrations on large strain elastic behaviors of gellan gels are studied in demonstrating how each parameter relies on the concentration. Plane-strain (simple shear) responses are also presented for gellan gels with different polymer concentrations.

A direct, unified approach was proposed toward achieving a simultaneous simulation of large elastic strain behaviors of gellan gels for different gellan polymer concentrations. Each parameter incorporated in the proposed elastic potential will be derived as a function of the polymer concentration in an explicit form, in the very sense of simultaneously simulating large strain data for different concentrations.

The purpose of this paper is to evaluate the forecasting performance of grey prediction models on educational attainment vis-à-vis that of exponential smoothing combined with multiple linear regression employed by the National Center for Education Statistics (NCES).

An out-of-sample forecasting experiment was carried out to compare the forecasting performances on educational attainments among GM(1,1), GM(1,1) rolling, FGM(1,1) derived from the grey system theory and exponential smoothing prediction combined with multivariate regression. The predictive power of each model was measured based on MAD, MAPE, RMSE and simple F-test of equal variance.

The forecasting efficiency evaluated by MAD, MAPE, RMSE and simple F-test of equal variance revealed that the GM(1,1) rolling model displays promise for use in forecasting educational attainment.

Since the possible inadequacy of MAD, MAPE, RMSE and F-type test of equal variance was documented in the literature, further large-scale forecasting comparison studies may be done to test the prediction powers of grey prediction and its competing out-of-sample forecasts by other alternative measures of accuracy.

The findings of this study would be useful for NCES and professional forecasters who are expected to provide government authorities and education policy makers with accurate information for planning future policy directions and optimizing decision-making.

As a continuing effort to evaluate the forecasting efficiency of grey prediction models, the present study provided accumulated evidence for the predictive power of grey prediction on short-term forecasts of educational statistics.

To investigate the relationship between key users (defined as their influence) in “information”, “purchase”, “communication” or “entertainment” networks, and the number of elicited requirements in web‐based information systems (WIS).

A lab experiment was designed and conducted to investigate the relationship between college students' elicited requirements for two WIS cases and their social networks.

The individual centrality in “information” networks has a significant positive relationship with the numbers of elicited “information” requirements and total requirements; however, the individual centrality in other social networks has no significant relationship with the number of the elicited requirements.

The requirements collected from “key users” may account for most requirements, which is similar to the results predicted by Pareto's rule.

The origin of a WIS depends on a few influential users. These key users possess more power than others, and they define not only the “requirements” of the site but also its content or knowledge. The WIS designers may take advantage of this fact.

This paper fills the information requirement elicitation gap, while transferring the conventional IS development experiences to WIS.

Large‐scale projects involve many organizations coming from different geographical locations. The task of coordination and information sharing/exchange therefore becomes very challenging. Recently, Web‐based project management systems have been developed and applied in construction project management. Presents an intelligent Web‐based project management system, called VHBuild.com, developed by the authors, which integrates project management, knowledge management and artificial intelligence technologies. First, discusses the advantages of using VHBuild in project management, which is followed by an in‐depth discussion on a number of artificial intelligence techniques. With the intelligent supports embedded in the VHBuild, the decision‐making procedure will no longer appear to be a blind‐searching process and project managers will not only be better informed, but also be given more efficient tools in tackling problems in managing large scale projects.

This study aims to discuss the state-of-the-art digital factory (DF) development combining digital twins (DTs), sensing devices, laser additive manufacturing (LAM) and subtractive manufacturing (SM) processes. The current shortcomings and outlook of the DF also have been highlighted. A DF is a state-of-the-art manufacturing facility that uses innovative technologies, including automation, artificial intelligence (AI), the Internet of Things, additive manufacturing (AM), SM, hybrid manufacturing (HM), sensors for real-time feedback and control, and a DT, to streamline and improve manufacturing operations.

This study presents a novel perspective on DF development using laser-based AM, SM, sensors and DTs. Recent developments in laser-based AM, SM, sensors and DTs have been compiled. This study has been developed using systematic reviews and meta-analyses (PRISMA) guidelines, discussing literature on the DTs for laser-based AM, particularly laser powder bed fusion and direct energy deposition, in-situ monitoring and control equipment, SM and HM. The principal goal of this study is to highlight the aspects of DF and its development using existing techniques.

A comprehensive literature review finds a substantial lack of complete techniques that incorporate cyber-physical systems, advanced data analytics, AI, standardized interoperability, human–machine cooperation and scalable adaptability. The suggested DF effectively fills this void by integrating cyber-physical system components, including DT, AM, SM and sensors into the manufacturing process. Using sophisticated data analytics and AI algorithms, the DF facilitates real-time data analysis, predictive maintenance, quality control and optimal resource allocation. In addition, the suggested DF ensures interoperability between diverse devices and systems by emphasizing standardized communication protocols and interfaces. The modular and adaptable architecture of the DF enables scalability and adaptation, allowing for rapid reaction to market conditions.

Based on the need of DF, this review presents a comprehensive approach to DF development using DTs, sensing devices, LAM and SM processes and provides current progress in this domain.