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This paper aims to make clear the sensitive zone of subsea pipeline to stress corrosion cracking (SCC) under a disbonded coating.

The change of microenvironment under a disbonded coating in artificial seawater was analyzed by using a rectangular crevice cell. The SCC behavior of subsea pipeline was studied by slow strain rate tensile tests.

The microenvironment at the crevice bottom exhibits obvious acidification, Cl- aggregation and cathodic protection potential (CP) rise. Accordingly, the susceptibility of X70 steels to SCC is high due to the intensive anodic dissolution effect. At the opening, hydrogen atom can access into the steel and induce hydrogen embrittlement effect on account of the applied over-protected CP potential, resulting in a relatively high susceptibility to SCC. The corrosiveness of the microenvironment at crevice middle, however, is mild with proper CP potential; thus, the susceptibility of X70 steel to SCC here is lower than that obtained at the opening and the crevice bottom.

A rectangular crevice cell is built to survey the microenvironment evolution under a disbonded coating in situ. The sensitive zone of subsea pipeline to SCC under a disbonded coating is clarified.

The purpose of this paper is to investigate two issues: understanding how Chinese equipment manufacturing firms can achieve successful independent innovation; and studying the roles of technology management (TM) and technological capability (TC) in independent innovation. The paper will develop a new model for independent innovation for China's equipment manufacturing firms.

The paper reviews literature related to independent innovation models, then develops a theoretical framework combining and integrating research from different fields. First, it examines how indexes of independent innovation are defined from the perspectives of technology, patents, standard, R&D and the market. Second, technology management and technological capability are interpreted. Third, relationships among TM, TC, and independent innovation are theoretically analyzed and discussed. Based on these, the paper conducts an in‐depth case study of Harbin Electric Corporation to explain how independent innovation is achieved from perspectives of TM and TC. Finally, the paper constructs and discusses the double helix model of TC and TM for independent innovation.

The paper finds that: technology management and technological capability both exert important influences on successful independent innovation; the improvement of TC follows cyclical steps of acquisition, assimilation and improvement, and TM is promoted by reforming and updating strategy management, organization management, regulation management and resource‐quality management; TM and TC have interactive effects; and TM and TC are coupled in the form of a double helix to realize independent innovation.

The paper provides new aspects of technology management, technological capability and their interaction to deconstruct independent innovation. The paper also offers insights in presenting a detailed case study of on‐the‐ground innovation and upgrading in China.

A lack of suitably qualified Building Information Modelling (BIM) professionals is understood to be a major barrier towards higher uptakes of BIM in the Australian construction industry. In response, Australian universities have tried to integrate the teaching of BIM into construction-related curricula, but with limited success. The acknowledged impediment is the lingering mismatch between what universities offer and what industry actually needs. However, the exact nature of that mismatch has yet to be identified. This study addresses that knowledge gap. It assesses both the current status of BIM competencies among university graduates and explores how BIM education at Australian universities may be improved to deliver BIM work readiness, as required by the industry.

This paper employed a qualitative research approach, utilizing 17 semi-structured interviews with experts in the Australian BIM industry. The Person-Organization (PO) fit theory, which emphasizes the congruence between individual and organizational characteristics, was utilized as a theoretical framework to examine the compatibility between “demand” and “ability” perspectives. The resulting data were analysed using this theoretical framework to gain insights into the PO fit perspectives in relation to BIM industry practices.

Findings reveal that graduates are generally competent regarding the use of BIM software. However, employers require much more than software skills, and expect recruits to have the capability to implement BIM as a process according to information management standards. Specifically, graduates are significantly deficient in matters of BIM protocols, collaboration and coordination, information workflows as well as completion and handover procedures.

This study is the first of its kind that bridges the gap between industry expectations and university education, in the Australian context, moving beyond the common discourse in education literature, which is exclusively focused on assessing students’ perceptions about BIM.

The application of dry-type transformers is growing in the market because the technology is non-flammable, safer and environmentally friendly. However, the unit dimensions are normally larger and material costs become higher, as no oil is present for dielectric insulation or cooling. At designing stage, a transformer thermal model used for predicting temperature rise is fundamental and the modelling of cooling system is particularly important. This paper aims to describe a thermal model used to compute dry transformers with different cooling system configurations.

The paper introduces a fast-calculating thermal and pressure network model for dry-transformer cooling systems, preliminarily verified by analytical methods and advanced CFD simulations, and finally validated with experimental results.

This paper provides an overview of the network model of dry-transformer cooling system, describing its topology and its main variants including natural or forced ventilation, with or without cooling duct in the core, enclosure with roof and floor ventilation openings and air barriers. Finally, it presents a formulation for the new heat exchanger element.

The network approach presented in this paper allows to model efficiently the cooling system of dry-type transformers. This model is based on physical principles rather than empirical assessments that are valid only for specific transformer technologies. In comparison with CFD simulation approach, the network model runs much faster and the accuracies still fall in acceptable range; therefore, one is able to utilize this method in optimization procedures included in transformer design systems.

The human-following task is a fundamental function in human–robot collaboration. It requires a robot to recognize and locate a target person, plan a path and avoid obstacles. To enhance the applicability of the human-following task in various scenarios, it should not rely on a prior map. This paper aims to introduce a human-following method that meets these requirements.

For the identification and localization of the target person (ILTP), this paper proposes an approach that integrates data from a camera, a light detection and ranging (LiDAR) and a ultra-wideband (UWB) anchor. For path planning and obstacle avoidance, a modified timed-elastic-bands (TEB) algorithm is introduced.

Compared to the UWB-only method, where only UWB is used to locate the target person, the proposed ILTP method in this paper reduces the localization error by 41.82%. Experimental results demonstrate the effectiveness of the ILTP and the modified TEB method under various challenging conditions. Such as crowded environments, multiple obstacles, the target person being occluded and the target person moving out of the robot’s field of view. The complete experimental videos are available for viewing on https://youtu.be/ZKbrNE1sePM.

This paper offers a novel solution for human-following tasks. The proposed ILTP method can recognize the target person among multiple individuals, determine whether the target person is lost and publish the target person’s position at a frequency of 20 Hz. The modified TEB algorithm does not rely on a prior map. It can plan paths and avoid obstacles effectively.

In corridor environments, human-following robot encounter difficulties when the target turning around at the corridor intersections, as walls may cause complete occlusion. This paper aims to propose a collision-free following system for robot to track humans in corridors without a prior map.

In addition to following a target and avoiding collisions robustly, the proposed system calculates the positions of walls in the environment in real-time. This allows the system to maintain a stable tracking of the target even if it is obscured after turning. The proposed solution is integrated into a four-wheeled differential drive mobile robot to follow a target in a corridor environment in real-world.

The experimental results demonstrate that the robot equipped with the proposed system is capable of avoiding obstacles and following a human target robustly in the corridors. Moreover, the robot achieves a 90% success rate in maintaining a stable tracking of the target after the target turns around a corner with high speed.

This paper proposes a human target following system incorporating three novel features: a path planning method based on wall positions is introduced to ensure stable tracking of the target even when it is obscured due to target turns; improvements are made to the random sample consensus (RANSAC) algorithm, enhancing its accuracy in calculating wall positions. The system is integrated into a four-wheeled differential drive mobile robot effectively demonstrates its remarkable robustness and real-time performance.

This paper aims to take Chinese university teachers as the research objects to examine their self-evaluation of online teaching and analyze the main factors influencing their evaluation during COVID-19.

According to the theory of educational ecology, the factors influencing teachers' self-evaluation of online teaching in this paper include university background, courses background and teachers' personal background from the macro- to micro-levels. Through exploratory factor analysis, independent sample T-test and one-way analysis of variance (ANOVA), the self-evaluation of online teaching of 13,997 teachers from 334 universities and their relationship with teachers' background have been subject to data statistics and analysis.

Teachers' self-evaluation of online teaching mainly includes three dimensions: online teaching methods, online teacher–student interaction and online teaching techniques. There are significant differences in these three dimensions among teachers with different background characteristics, including regions, the types of universities, the nature of universities in macro background levels, the types and numbers of online courses in meso background levels, and the gender, years of teaching, professional titles and disciplines in micro background levels.

To improve teachers' self-evaluation of online teaching, it is suggested to build an online teaching self-evaluation system for teachers, strengthen university support and guarantee, strengthen online teaching training and improve the information accomplishments of teachers.

This large-scale empirical survey of online teaching evaluation of Chinese teachers can provide scholars with a deeper understanding of the implementation of online teaching in China and the self-evaluation of online teaching by teachers.

This study aims to develops a new-type low-alloy corrosion resistant steel containing Sb and investigate the corrosion mechanism of this new-type low-alloy steel.

Energy dispersive spectrometer, X-ray photoelectron spectroscopy, X-Ray diffraction and scanning electron microscopy were used to evaluate the corrosion resistance of the rust layers formed on these samples. Laser confocal microscopy was used to observe the corroded surfaces of the steels.

Results showed that Sb added can consume H⁺ in the solution, thereby preventing the oxygen reaction to slow down the corrosion rate. Meanwhile, a stable and insoluble substance (Sb₂O₃) in the acidic solution would be produced when the reaction of the product of Sb and H⁺ with the enough dissolved oxygen in the solution. Due to the precipitation of Sb₂O₃ and iron oxyhydroxides, the rust layer of Sb-containing steel became more uniform and compact, which resulted in better corrosion resistance in acid environment.

In this study, a new-type acid resistant low-alloy steel containing Sb was developed. Compared with the results, the corrosion mechanism of the new-type low-alloy steel in acid environment was discussed.

This paper aims to propose a new strategy to functionalize zeolitic imidazolate frameworks (ZIF-8) to improve its dispersion stability and tribological properties in lubricating oil.

Dialkyl dithiophosphate polydopamine ZIF-8 (DDP@PDA@ZIF-8) was prepared via mussel-inspired chemistry and the Michael addition reaction. The tribological properties of DDP@PDA@ZIF-8 as an additive in the white oil were evaluated with four-ball friction and wear tester at different temperatures. The worn surface was analyzed using X-ray photoelectron spectrum (XPS).

The as-prepared DDP@PDA@ZIF-8 shows high dispersion stability in the white oil. Tribological results confirmed that the DDP@PDA@ZIF-8 exhibited a small wear scar diameter at 25°C. However, excellent friction reduction and anti-wear properties were observed at 75°C. The XPS result indicates that a series of tribochemical reactions occurred on the worn surface, forming the complex protective film.

This paper provides a study of highly dispersed ZIF-8 as lubrication additives.

Financial flexibility and investment efficiency are of vital importance in strategic choices at boardrooms, particularly in post-crisis recovery strategies. This study examines the moderating effects of investment efficiency and investment scale on the relationship between financial flexibility and firm performance.

The authors use sample of 10,755 US-listed firms over the period 2010–2021 to examine the relationships between investment scale, investment efficiency, financial flexibility and firm performance. Particular attention is paid to overinvestment and underinvestment.

Findings of this study reveal that financial flexibility mitigates investment inefficiency through reducing overinvestment. Financial flexibility contributes to boost a firm’s accounting and market performance. Additionally, investment efficiency and investment scale have moderating effects on the relationship between financial flexibility and firm performance. However, the influence of investment efficiency is greater than the influence of investment scale. Finally, the authors find that the direct and indirect effects of financial flexibility are stronger on market performance than accounting performance, implying that market is more sensitive to corporate financial policies.

Findings of this study have implications for scholars, decision-makers policymakers, investors and other stakeholders.

This study has its own limitations due to the sample selection issues, country context and the research model adopted by this study.

The novel contribution to the extant literature is incorporating the influence of investment scale and investment efficiency into the relationship between financial flexibility and firm performance.