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The purpose of this paper is to document the relationship between intra-group coopetition and subsidiaries' innovation performance and the moderating impact of the intensity of external competition.

Data were collected from 75 subsidiaries in China through a questionnaire survey of their R&D and general managers. The total number of individual respondents was 205. We tested our hypothesis by using ordinary least squares regression.

Intra-group cooperation was found to promote a subsidiary's performance in product and process innovation. Intra-group competition was found to have a U-shaped relationship with product and process innovation. Intra-group cooperation strengthens the U-shaped relationship between intra-group competition and process innovation.

This study involved firms from more than one industry. Studies of specific industries might reach more specific conclusions. And all of the data were self-reported by the managers of the firms concerned. Future studies would be well-advised to consider more objective data describing pairs of parent firms and subsidiaries.

Subsidiaries ought to build their internal networks to cooperate with each other. That can bring significant advantages in terms of information and synergy in innovation. Subsidiaries are also suggested to take full advantage of the opportunities that intra-group competition brings.

This study is the first one to explore coopetition phenomenon in the context of business group. By taking Chinese business group subsidiaries as the research samples, this research not only extends the coopetition research but also reveals that cooperation and competition are co-existed and exert influence in subsidiaries.

To enrich the research on the economic consequences of enterprise digital development from the perspective of capacity utilization.

Using a sample of listed firms from 2010 to 2020, this paper exploits text analysis of annual reports to construct a proxy for enterprise digital development.

Results show that enterprise digital development not only improves their own capacity utilization but also generates a positive spillover effect on the capacity utilization of peer firms and firms in the supply chain. Next, based on the incomplete information about market demand and potential competitors when making capacity-building decisions, the mechanism tests show that improving the accuracy of market forecasts and reducing investment surges are potential channels behind the baseline results. Cross-sectional tests show the baseline result is more pronounced when industries are highly homogeneous and when firms have access to less information.

This paper contributes to the research related to the economic consequences of digital development. With the development of the digital economy, the real effects of enterprise digital development have also triggered extensive interest and exploration. Existing studies mainly examine the impact on physical operations, such as specialization division of labor, innovation activities, business performance or total factor productivity (Huang, Yu, & Zhang, 2019; Yuan, Xiao, Geng, & Sheng, 2021; Wang, Kuang, & Shao, 2017; Li, Liu, & Shao, 2021; Zhao, Wang, & Li, 2021). These studies measure the economic benefits from the perspective of the supply (output) side but neglect the importance of the supply system to adapt to the actual market demand. In contrast, this paper focuses on capacity utilization, aimed at estimating the net economic effect of digital development by considering the supply-demand fit scenario. Thus, our findings enrich the relevant studies on the potential consequences of digital development.

The regulations for qualitative genetically modified (GM) food labeling do not effectively eliminate the information asymmetries pertaining to the consumption of GM products. China's GM food labeling law requires the presentation of certain categories of GM products on GMO labels on packages. Such information is invaluable for understanding whether the disclosure of more information on GM foods can help alleviate information asymmetry while reducing consumer fear and risk perceptions of GM foods, and thus cause changes in their behaviors. The purpose of this paper is to explore the heterogeneity of consumer preferences for enhanced GM food labeling, how consumer preferences are influenced by labeling information, and how these preferences vary in different consumers.

Both descriptive statistics and econometric techniques, including the multivariate ordered Probit model, were applied to a sample of 566 urban consumers in the Yangtze River Delta region of China. All respondents were divided into two groups: people who would definitely not buy GM foods before selecting enhanced labeling information (“consumer group 1”, sample size 282) and people who would definitely not object to buying GM foods before selecting enhanced labeling information (“consumer group 2”, sample size 274).

The findings suggest that urban consumers have a preference for different types of enhanced labeling information about GM foods, that such a preference significantly influences their willingness to pay for GM foods, that there exists a large difference in the preferences of different consumer groups, and that enhanced GM food labeling information has a greater impact on those consumers who would not accept GM foods.

This research identifies the GM information disclosures that most affect consumer preferences and how these preferences vary across different segments of consumers, which is a current gap in the literature. The study has demonstrated that enhanced labels of GM foods with diverse information would not alter a consumer's WTP for GM foods who does not perceive the value of information from the enhanced labels, but change positively consumers with uncertainty willingness to pay before disclosure.

The purpose of this study was to investigate the tribological properties of bulk Fe₂B with pre-oxidation treatment.

Bulk Fe₂B was oxidized in an electric box furnace with a soaking time of 9 min under 750°C in air. Then, the tribological experiments were carried out on an UMT-Tribolab tester.

The oxide layer was composed of Fe, Fe₂O₃, Fe₃O₄, B₂O₃ and H₃BO₃. The oxidative direction of bulk Fe₂B was perpendicular to the sample surface. But, the oxidative direction of Fe₂B crystals was irregular. At 0.1 m/s, the friction coefficient was the lowest. The effects of shortening the running-in period of friction and reducing the friction coefficient by pre-oxidation treatment at 0.1 m/s were remarkable. Nevertheless, the effect of pre-oxidation treatment was futile at 0.2 m/s. Wear mechanisms of oxidized Fe₂B mainly were adhesive and abrasive wear.

The effects of shortening the running-in period of friction and reducing the friction coefficient by pre-oxidation treatment were remarkable.

Salt rock from salt lakes can serve as a cost-effective material for subgrade filling, as demonstrated in projects like the Qarhan Salt Lake section of the Qinghai-Tibet Railway and the Qarhan Salt Lake section of the G215 Highway. This state-of-the-art paper aims to summarize the engineering properties of salt rock filling and present the advances of its utilization.

This paper collects and analyzes laboratory and field data of salt rock filling from previous studies to present a comprehensive analysis of the engineering properties and utilization of salt rock fillings.

Salt rock primarily contains minerals such as halite and glauberite, which contribute to its unique phase-changing behavior under varying environmental conditions, impacting its mechanical properties. Salt rock filling shrinks when in contact with vapor or unsaturated brine and expands under cooling or evaporation. Its use is particularly recommended for arid regions, with specific restrictions depending on the structure type. This paper discusses suggested countermeasures to mitigate these issues, as well as key quality acceptance indices for salt rock filling compaction. Moisture content after air-drying is recommended as a crucial parameter for construction quality control.

This review aims to support future research and engineering practices in salt rock subgrade applications.

The purpose of this paper is to develop a novel integrated risk assessment method from the system perspective to evaluate the risk of the cross-regional mega construction project (CMCP). Furthermore, this paper aims to confirm the core risk source factors and refine the risk management strategies of CMCPs through a case study.

Based on the analysis of the risk system of CMCPs, the concept model and risk assessment principles of integrated risk assessment were confirmed. The risk source factors and project objectives of the CMCP were identified from a literature review, export interview and case analysis. According to the vulnerability theory, the integrated risk assessment model was developed by involving vulnerabilities, threats, objectives and interaction of those factors synthetically. Then, ZW high-speed railway from China was analyzed to verify the feasibility and effectiveness of the proposed method.

As a result, 12 threat factors and 12 vulnerability factors were identified. Based on the case study, the main external threat comes from T13 (conflicts of interest between local governments) and T23 (harsh natural environment); the most easily exploited internal vulnerabilities were V11 (complexity of technology), V13 (lack of experience in technical application), V21 (inadequate experience) and V23 (lack of interest coordination mechanism). Moreover, the economic objective was most affected.

It is essential to develop an interest coordination mechanism for CMCPs. The harsh natural environment is a critical factor, but it also promotes technological innovation and iteration. Public opinions in different regions are critical for CMCPs, and more emphasis should be placed on public opinion surveys of CMCPs. Moreover, diverse and flexible environmental protection strategies should apply in CMCPs.

This research has the following three contributions. First, based on vulnerability theory, an integrated risk assessment approach of CMCPs is developed, which enriches the risk measurement method system and provides inspiration for future research on risk in the construction industry. Second, the risk sources of CMCPs are identified from the perspective of vulnerability and threat to provide clear guidance for the risk management of CMCPs. Third, the core risk source factors and management strategies confirmed by the case study will be beneficial for various governments in different regions and project managers to optimize the project management scheme, as they are transferable management experiences.

Electrical impedance tomography (EIT) is a technique for reconstructing the conductivity distribution by injecting currents at the boundary of a subject and measuring the resulting changes in voltage. Image reconstruction for EIT is a nonlinear problem. A generalized inverse operator is usually ill-posed and ill-conditioned. Therefore, the solutions for EIT are not unique and highly sensitive to the measurement noise.

This paper develops a novel image reconstruction algorithm for EIT based on patch-based sparse representation. The sparsifying dictionary optimization and image reconstruction are performed alternately. Two patch-based sparsity, namely, square-patch sparsity and column-patch sparsity, are discussed and compared with the global sparsity.

Both simulation and experimental results indicate that the patch based sparsity method can improve the quality of image reconstruction and tolerate a relatively high level of noise in the measured voltages.

EIT image is reconstructed based on patch-based sparse representation. Square-patch sparsity and column-patch sparsity are proposed and compared. Sparse dictionary optimization and image reconstruction are performed alternately. The new method tolerates a relatively high level of noise in measured voltages.

The purpose of this paper is to propose a DC-port voltage balance strategy realizing it by logic combination modulation (LCM). This voltage balance strategy is brief and high efficient, which can be used in many power electronic devices adopting the cascaded H-bridge rectifier (CHBR) such as power electronic transformer (PET).

The CHBR is typically as a core component in the power electronic devices to implement the voltage or current conversion. The modulation method presented here is aiming to solve the voltage imbalance problem occurred in the CHBR with more stable work station and higher reliability in ordinary operating conditions. In particular, by changing the switch states smoothly and quickly, the DC-port voltage can be controlled as the ideal value even one of the modules in CHBR is facing the load-removed problem.

By using the voltage balance strategy of LCM, the problem of voltage imbalance occurring in three-phase cascaded rectifiers has been solved properly. With the lower modulation depth, the efficiency of the strategy is shown to be better and stronger. The strategy can work reliably and quickly no matter facing the problem as load-removed change or the ordinary operating conditions.

The limitation of the proposed DC-port voltage balance strategy is calculated and proved, in a three-module CHBR, the LCM could balance the DC-port voltage while one module facing the load-removed situation under 0.83 modulation depth.

This paper provides a useful and particular voltage balance strategy which can be used in the topology of three-phase cascaded rectifier. The value of the strategy is that a brief and reliable voltage balance method in the power electronic devices can be achieved. What is more, facing the problem, such as load-removed, in outport, the strategy can response quickly with no switch jump and switch frequency rising.

The purpose of this paper is to forecast the reliable storage life of a certain kind of equipment under the normal stress level.

Through the stepping stress acceleration life test and the failure mechanism analysis, this paper aims to confirm the stress level for the stepping stress acceleration life test of a certain kind of equipment and establish the data processing mathematical model and storage life forecasting method.

The stress level for the stepping stress acceleration life test of a certain kind of equipment is confirmed and the data processing mathematical model and storage life forecasting method is established.

Availability of data is the main limitation affecting which model will be applied.

Useful advice for products' storage life forecasting.

The paper presents a new approach to product storage life estimation.

Steel structures are easily corroded under coastal atmospheric environment due to high humidity and high saltwater spray. To extend service life of steel structure infrastructure, it is necessary to remove rust and apply paint on the steel structure once a year. However, existing wall-climbing sandblasting robots are difficult to work on narrow steel beams and cause serious environmental pollution. The purpose of this study is to design a robot that can effectively remove rust from narrow steel beams and reduce environmental impact to extend the service life of steel structure infrastructure.

The heavy-duty wall-climbing robot designed in this study can effectively solve the above problems. The robot achieves adjustable magnetic adsorption force of the permanent magnet adsorption through a novel switch design and can work flexibly and stably on narrow steel beams through a worm-like internal and external alternating motion structure. In addition, it is equipped with a sandblasting recovery device to reduce environmental pollution.

The on-site test results on steel beams show that trust removal level can reach Sa2.0. The recovery rate of sandblasting and rust removal is close to 95%. The robot can carry a 40 kg sandblasting equipment and move at a speed greater than 40 cm/min, indicating that it can efficiently complete the rust removal work of narrow steel structures.

The originality lies in the design of the robot with features such as adjustable magnetic adsorption, special motion structure for narrow beams and a sandblasting recovery device. The value is that it can solve the problems of existing robots in working on narrow steel beams and environmental pollution and effectively extend the service life of steel structure infrastructure by efficiently removing rust.