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The measurement of geomagnetic field can provide a reliable and economical basis for attitude and orbit information of low earth orbiting satellite. Because the earth's magnetic field is a function of position, and its measurement on the orbit are fully observable, orbit estimation can be obtained using extend Kalman filter (EKF) algorithm. With the assistant of angle velocity information from gyro measurement, attitude estimation can also be obtained. At the same time, gyro drift rate estimation is a part of the filter output. Although orbit and attitude determination are independent of each other, the filter can give the orbit and attitude estimation at the same time. The results of the numerical test show that a signal EKF can estimate both orbit and attitude by using magnetometer and gyro measurement only. The accuracy, usually is sufficient for low earth orbiting satellites.

Automatic guided vehicles (AGVs) are widely used in industrial fields. But most control strategies merely take the lateral force into consideration. This will reduce the accuracy, stability and robustness and will pay additional costs. Therefore, this paper aims to design a control strategy that initially considers lateral force. Thereby, it will improve the accuracy, stability and robustness and reduce the overall cost of AGV.

To achieve the goal of comprehensively improving AGV operating performance, this paper presents a new scheme, combining the dual-wheeled chassis model (DCM) using proportional–integral–differential (PID) control and a supporting quick response (QR) code navigation technology. DCM is the core, which analyzes the deviation caused by lateral force. Then, DCM with PID control by the control law is combined to suppress the errors. Meanwhile, QR code navigation technology provides effective data support for the control strategy.

Most AGV experiments are carried out in a standard environment. However, this study prepares unfavorable scenarios and operating conditions for the experiments that generate detailed data to demonstrate this study’s strategy, which can make an accurate, stable and robust operation process of AGV under various adverse environmental and mechanical factors.

This study proposed DCM, fully considering lateral force and converting the force into velocity. Subsequently, PID controls the speed of two wheels to reduce the error. QR code provides an efficient and low – cost way to obtain information. The three are cleverly combined as a novel industrial AGV control strategy, which can comprehensively improve the operating performance while reducing overall costs.

Previous studies have produced inconsistent findings regarding the effects of resource constraints on corporate illegal behavior. This study aims to explore how entrepreneurial firms can overcome the difficulties generated by resource constraints.

Drawing on insights from general strain theory and focusing on listed entrepreneurial firms, this study proposes that failure to obtain enough resources through listing generates strain in the managers of listed entrepreneurial firms, driving them to resort to corporate financial fraud as a solution. Nevertheless, such relationships between resource constraints and the likelihood of corporate financial fraud can be weakened by innovation capability, because innovation capability can generate more confidence in their managers and relieve their strains, thereby dissuading them from engaging in corporate financial fraud.

According to our empirical results, both financial and human resource constraints are positively related to the likelihood of corporate financial fraud in listed entrepreneurial firms, but such effects can be mitigated by innovation capability.

This study provides practical implications for both regulators and managers by indicating that although entrepreneurial firms with resource constraints are more likely to commit financial fraud, innovation capability could be a strategic approach to enhance managers’ confidence and relieve the strain.

Our study contributes to the literature by enriching our understanding of the consequences of resource constraints in entrepreneurial firms and highlighting the strategic importance of innovation capability in mitigating such effects.

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.

This study aims to develop a moderated mediation model to explain the practices of supply base management and how they can achieve innovation performance, and the authors explore the boundary conditions of this implementation mechanism.

The authors used the bootstrap procedure to conduct empirical tests on 328 Chinese manufacturers to verify the proposed model.

The results showed that supplier innovation focus, supply-base structuring and long-term relationship focus have a positive impact on innovation performance through supplier innovativeness, and the mediation performs differently under technology and demand uncertainty.

The authors only focused on innovation performance, and it does not explore the links between supply base management and other performance outcomes. This study involves part of the supply network which is easier to manage, i.e. supply base. The authors ignored the importance of other members in supply network. Finally, the data obtained in this study belong to the cross-sectional data during the same period but it accomplishes the research aim well.

The focal firm needs to improve their supply base composition, establish permeable organizational boundaries, and build long-term strategic partnerships characterized by equality and trust with suppliers to stimulate supply base members to make innovative contributions.

This study complements the implementation path of manufacturers around innovation, emphasizing multidimensional characteristics of supply base management. And this study clarifies the mechanism and boundary conditions between supply base management and innovation performance.

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.

The purpose of this paper is to investigate linkages among competitive strategy, strategic capabilities, environmental uncertainty, and organizational performance in small and medium sized enterprises (SMEs) in China and the USA.

In China, a survey was administered to managers of SMEs in Shanghai and Guangzhou. In the USA, a survey was administered to managers of SMEs in three major cities. Competitive strategy, capabilities, uncertainty, and performance were measured by previously validated scales.

Findings support the integrity Miles and Snow generic strategic typology. Performance satisfaction was significantly lower in firms employing a reactor strategy as opposed to those employing prospector, defender, or analyzer strategies. Additional support was found for the concept of strategic clarity, as businesses reporting moderate strategic clarity had lower levels of satisfaction with performance than those reporting either a single strategy or a combination emphasis on three equal strategies.

Chinese SMEs tend to prefer cost-based approaches to their local markets. A differentiation market approach is challenging in most local Chinese economies due to the low wages of most jobs in an economy that is still largely centrally planned. In the USA, more disposable income leads to more market opportunities. While this situation is gradually changing in China, it is not at a point where SMEs feel comfortable pursuing totally differentiated strategies.

Several distinctions in competitive strategy, capabilities, and environmental uncertainty between China and the USA are recognized by analysis. Analyzers and defenders in Chinese SMEs tend to follow industry prospectors with lower prices and/or superior service. They might change strategies after gaining a foothold in the market. Performance for SMEs with low strategic clarity often depends on established guanxi with governmental agencies or stated-owned enterprises, a situation very different from that in the USA.