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This paper aims to provide a 3D finite element (FE) model for dynamic simulation of cutterhead and soil interaction in slurry shield tunneling.

Dynamic numerical simulation of excavation process is realized by combined use of submodeling method and arbitrary Lagrangian Eulerian (ALE) approach. The model size reduction, soil mesh refinement and stress state initialization are fulfilled by submodeling. The large soil deformations, failures and flows are handled by ALE approach. Computation time is reduced by parallel domain decomposition with recursive coordinate bisection method. Validation of the proposed approach is achieved by comparing the numerical results with monitored data from the model test for Yangtze River tunneling project.

The proposed approach proves to be an effective technique to simulate the cutterhead and soil interaction dynamically in tunnel excavation. Comparative study on the effect of mesh density indicates the requirement of relative mesh refinement. Exploration of the parallel computing performance points out the best decomposed domain for the simulation. Parametric study on the effect of rotary speed and investigation on soil properties presents the significant factors for torque.

The proposed numerical model can help in the development process of reduced‐scale model test, as well as design and selection of slurry shield machines.

The originality comes from the need to evaluate the excavation performance of slurry shield machine in tunneling project. This contribution provides a 3D numerical approach, which takes into account the stress state in soil and dynamic contact effects between soil and cutterhead. In this work, large deformation in soil is handled. Besides, soil failures and flows are captured.

Small firms in China anticipate entrepreneurial opportunities for continual growth. However, they may fail to recognize opportunities because of their inefficiency in managing their knowledge.

In this explorative paper, the authors assess the opportunity recognition efficiency of 168 small Chinese firms using data envelopment analysis (DEA). Supplementary Tobit regressions were conducted for further exploring the factors that influence the firms’ efficiency in opportunity recognition.

Results from the DEA suggest that most respondents recognize significantly fewer opportunities than those with equivalent knowledge stock. Moreover, many firms have low levels of pure technical efficiency but high levels of scale efficiency, indicating insufficient use of knowledge as a major reason for inefficiency in opportunity recognition. The Tobit regressions show that sales and research and development intensity are relevant to a firm’s opportunity recognition efficiency.

This study calls for the investigation of efficiency issues in opportunity recognition and suggests that managers guard against unwarranted loss of opportunities owing to inefficient use of existing knowledge elements.

First, the authors introduce the concept of opportunity recognition efficiency within the entrepreneurial process. Second, they manifest the role of knowledge management in opportunity recognition. Third, they introduce DEA to investigate the relationship between knowledge stock and opportunity recognition. Fourth, this study reveals that inefficient use of knowledge is a disadvantage of small Chinese firms in terms of opportunity recognition.

This study aims to show the importance of natural convection of supercritical fluid in an inclined cavity. The heat transfer performance of natural convection can be improved.

A model of an inclined cavity was set up to simulate the natural convection of supercritical fluid. The influence of inclined angles (30 to approximately 90°) and pressures (8 to approximately 12 MPa) are analyzed. To ascertain flow and heat transfer of supercritical fluid natural convection, this paper conducts a numerical investigation using the lattice Boltzmann method (LBM), which is proven to be precise and convenient.

The results show that the higher heat transfer performance can be obtained with an inclined angle of 30°. It is also presented that the heat transfer performance under pressure of 10 MPa is the best. In addition, common criterion number correlations of average Nusselt number are also fitted.

These study results can provide a theoretical reference for the study of heat transfer of supercritical fluid natural convection in engineering.

Based on the resource bricolage theory, we investigate the impact of proactive market orientation and responsive market orientation on firms’ disruptive green innovation. We also examine the impact of resource bricolage on disruptive green innovation and the mediating role of resource bricolage.

Quantitative data were collected from 232 firms in China. Structural equation modelling was used to test hypotheses.

The result show that proactive market orientation had positive effect on firm’s disruptive green innovation, whereas responsive market orientation had negative effect on firm’s disruptive green innovation. In addition, resource bricolage positively promotes firm’s disruptive green innovation. Resource bricolage played a mediating role between proactive market orientation and disruptive green innovation. Resource bricolage had a suppressing effect between responsive market orientation and disruptive green innovation.

This study makes up for the deficiency of the existing research on the relationship between market orientation and enterprise disruptive green innovation, improves the guidance mechanism of disruptive green innovation.