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This paper aims to develop a parallel fast neighbor search method and communication strategy for particle-based methods with adaptive smoothing-length on distributed-memory computing systems.

With a multi-resolution-based hierarchical data structure, the parallel neighbor search method is developed to detect and construct ghost buffer particles, i.e. neighboring particles on remote processor nodes. To migrate ghost buffer particles among processor nodes, an undirected graph is established to characterize the sparse data communication relation and is dynamically recomposed. By the introduction of an edge coloring algorithm from graph theory, the complex sparse data exchange can be accomplished within optimized frequency. For each communication substep, only efficient nonblocking point-to-point communication is involved.

Two demonstration scenarios are considered: fluid dynamics based on smoothed-particle hydrodynamics with adaptive smoothing-length and a recently proposed physics-motivated partitioning method [Fu et al., JCP 341 (2017): 447-473]. Several new concepts are introduced to recast the partitioning method into a parallel version. A set of numerical experiments is conducted to demonstrate the performance and potential of the proposed parallel algorithms.

The proposed methods are simple to implement in large-scale parallel environment and can handle particle simulations with arbitrarily varying smoothing-lengths. The implemented smoothed-particle hydrodynamics solver has good parallel performance, suggesting the potential for other scientific applications.

Promoting low-carbon in the construction industry is important for achieving the overall low-carbon goals. Public–private partnership is very popular in public infrastructure projects. However, different perceptions of low-carbon and behaviors of public and private sectors can hinder the realization of low-carbon in these projects. In order to analyze the willingness of each stakeholder to cooperate towards low-carbon goals, an evolutionary game model is constructed.

An evolutionary game model that considers the opportunistic behavior of the participants is developed. The evolutionary stable strategies (ESSs) under different scenarios are examined, and the factors that influence the willingness to cooperate between the government and private investors are investigated.

The results illustrate that a well-designed system of profit distribution and subsidies can enhance collaboration. Excessive subsidies have negative impact on cooperation between the two sides, because these two sides can weaken income distribution and lead to the free-riding behavior of the government. Under the situation of two ESSs, there is also an optimal revenue distribution coefficient that maximizes the probability of cooperation. With the introduction of supervision and punishment mechanism, the opportunistic behavior of private investors is effectively constrained.

An evolutionary game model is developed to explore the cooperation between the public sector and the private sector in the field of low-carbon construction. Based on the analysis of the model, this paper summarizes the conditions and strategies that can enable the two sectors to cooperate.

The purpose of this paper is to summarize the current applications of BIM, the integration of related technologies and the tendencies and challenges systematically.

Using quantitative and qualitative bibliometric statistical methods, the current mode of interaction between BIM and other related technologies is summarized.

This paper identified 24 different BIM applications in the life cycle. From two perspectives, the implementation status of BIM applications and integrated technologies are respectively studied. The future industry development framework is drawn comprehensively. We summarized the challenges of BIM applications from the perspectives of management, technology and promotion, and confirmed that most of the challenges come from the two driving factors of promotion and management.

The technical challenges reviewed in this paper are from the collected literature we have extracted, which is only a part of the practical challenges and not comprehensive enough.

We summarized the current mode of interactive use of BIM and sorted out the challenges faced by BIM applications to provide reference for the risks and challenges faced by the future industry.

There is little literature to integrate BIM applications and to establish BIM related challenges and risk frameworks. In this paper, we provide a review of the current implementation level of BIM and the risks and challenges of stakeholders through three aspects of management, technology and promotion.

A large, uneven settlement that is unfavourable to dam safety can occur between a concrete cut-off wall and the high-plasticity clay of earth core dam built on alluviums. This issue has been often studied using the small-strain finite element (FE) method in previous research. This paper aims to research the interaction behaviour between a concrete cut-off wall and high-plasticity clay using large-deformation FE analyses.

The re-meshing and interpolation technique with a small-strain (RITSS) method was performed using an independently developed program and adopted for large-deformation FE analyses, and a suitable element size for the high-plasticity clay region was suggested. The layered construction process of an earth core dam built on thick alluviums was simulated using the RITSS method incorporating a hyperbolic model for soil.

The RITSS method is an effective technique for simulating the soil–structure interaction during dam construction. The RITSS analysis predicted a higher maximum principle stress of the concrete cut-off wall and higher stress levels in the high-plasticity clay region than small-strain FE analysis.

A practical method for large-deformation FE analysis was advised and was used for the first time to study the interaction between a concrete cut-off wall and high-plasticity clay in dam engineering. Large deformation in the high-plasticity clay was handled using the RITSS method. Moreover, the penetration process of the concrete cut-off wall into the high-plasticity clay was captured using a favourable element shape and mesh density.

The purpose of this paper is to investigate how mentors affect the career satisfaction of protégés. Drawing from the Elaboration Likelihood Model (ELM), the authors propose a dual processing model that considers both cognition and emotion in the relationship between mentoring and the career satisfaction of protégés.

The study employed a three-stage questionnaire survey to collect data from employees in Chinese enterprises, resulting in a total of 329 valid responses.

The results showed that mentoring had a significant positive impact on protégé career satisfaction. Additionally, role clarity and positive affect of protégés played dual-mediating effects between mentoring and protégé career satisfaction. Moreover, as a non-mentoring behavior, mentor advice-seeking behavior strengthened the positive impact of mentoring on role clarity and positive affect.

In the study, the authors utilize the ELM as a new perspective to construct a dual-mediating model of protégé role clarity and positive affect to illuminate the mechanism of mentoring on protégé career satisfaction, advancing the literatures of mentoring relationship and career development. Further, the authors put forward the moderating effect of mentor advice-seeking behavior by considering it as a non-mentoring behavior of mentors to deepen the understanding of mentorships. Moreover, the authors attempt to propose the long-term cumulative effect of the dual processing to expand the application of the ELM in interpersonal processes.

The purpose of this study is to investigate the intergranular corrosion (IGC) susceptibility of a nitrogen-containing austenitic stainless steel QN2109. The intergranular corrosion (IGC) susceptibility of a nitrogen-containing austenitic stainless steel QN2109 was investigated.

The double-loop electrochemical potentiodynamic reactivation (DL-EPR) tests were carried out. Scanning electron microscopy and atomic force microscopy were used to characterize the microstructure.

The optimized test condition for QN2109 was 1 M H₂SO₄ + 0.01 M NH₄SCN at 40°C. The nose temperature of the temperature–time–sensitization (TTS) curve of QN2109 plot was approximately 750°C. Moreover, the IGC susceptibility started to appear at approximately 120 min. The Cr-depletion zone of QN2109 was generated by the formation of M23C6 rather than by the addition of nitrogen. The depth–width ratio of the grain boundaries after the DL-EPR tests decreased as the aging temperature increased. The degree of Cr depletion and size of the Cr-depletion zone at the grain boundary were reflected by the degree of sensitization and depth–width ratio, respectively.

The optimized test condition for DL-EPR tests of a nitrogen-containing austenitic stainless steel QN2109 was investigated. The TTS curve of QN2109 was first plotted to avoid IGC failure. The morphology of the Cr-depletion zone was reflected by the depth–width ratio.

Multiutility tunnel (MUT) has been recognised as a more sustainable method to place underground utilities than the traditional directly buried (DB) method. However, the implementation of MUT is hindered because of high initial construction costs and the difficulty to demonstrate its benefits, especially social benefits that are hard to be quantified. To address the limitation, this paper aims to quantify and compare both economic costs and traveller loss (i.e. an important part of social costs) of the MUT and DB method.

An agent-based model (ABM) is developed, which considers attributes and actions of vehicles, interactions between vehicles and interactions between vehicles and the road network. The ABM is used to estimate traveller loss by comparing traveller time when the MUT and DB method is adopted, respectively. The traveller loss is combined with economic costs to estimate and compare the LCC of the MUT and DB method. To verify the ABM-based approach, it is implemented in an MUT project in Shanghai, China.

Results of the study indicate: (1) When the DB method is adopted, periodic E&Rs cause severe traffic congestion and substantial traveller loss. (2) When traveller loss is not included in the LCC estimation, the DB method has a lower LCC in most scenarios. (3) When traveller loss is included, the relative LCC of MUT and the time it takes to cover the LCC of the MUT and DB method is largely reduced. Thus, when social costs are considered, MUT will bring more benefits than the DB method.

Previous studies on comparing the MUT and DB method focus on investigating economic costs, while other costs, e.g. social costs, are not well addressed quantitatively. Besides, current studies of traveller loss estimation lack consideration of factors such as unique attributes, actions and interactions of vehicles and the network. Hence, this paper applies an ABM-based approach to involve these factors and produce more reliable estimation of traveller loss than existing approaches. Moreover, by integrating traveller loss into LCC analysis, this paper helps to understand the benefits of MUT thus assisting decision-making in selecting utilities placement methods.

Unconventional machining processes, particularly ultrasonic vibration cutting (UVC), can overcome such technical bottlenecks. However, the precise mechanism through which UVC affects the in-service functional performance of advanced aerospace materials remains obscure. This limits their industrial application and requires a deeper understanding.

The surface integrity and in-service functional performance of advanced aerospace materials are important guarantees for safety and stability in the aerospace industry. For advanced aerospace materials, which are difficult-to-machine, conventional machining processes cannot meet the requirements of high in-service functional performance owing to rapid tool wear, low processing efficiency and high cutting forces and temperatures in the cutting area during machining.

To address this literature gap, this study is focused on the quantitative evaluation of the in-service functional performance (fatigue performance, wear resistance and corrosion resistance) of advanced aerospace materials. First, the characteristics and usage background of advanced aerospace materials are elaborated in detail. Second, the improved effect of UVC on in-service functional performance is summarized. We have also explored the unique advantages of UVC during the processing of advanced aerospace materials. Finally, in response to some of the limitations of UVC, future development directions are proposed, including improvements in ultrasound systems, upgrades in ultrasound processing objects and theoretical breakthroughs in in-service functional performance.

This study provides insights into the optimization of machining processes to improve the in-service functional performance of advanced aviation materials, particularly the use of UVC and its unique process advantages.

The purpose of this study is to improve the corrosion resistance of the transmission towers by Zinc-aluminum-magnesium (Zn-Al-Mg) coatings doped with rare earths lanthanum (La) and cerium (Ce) (denoted as Zn-Al-Mg-Re) in Q345 steel.

The phase structure of Zn-Al-Mg-Re composite coatings has been determined by X-ray diffraction, whereas their surface morphology and cross-sectional microstructure as well as cross-sectional elemental composition have been analyzed by scanning electron microscopy and energy-dispersive spectrometry. Moreover, the corrosion resistance of Zn-Al-Mg-Re composite coatings has been evaluated by acetic acid accelerated salt spray test of copper strip.

Experimental results show that doping with La and Ce favors to tune the composition (along with the generation of new phase, such as LaAl₃ or Al₁₁Ce₃) and refine the microstructure of Zn-Al-Mg galvanizing coatings, thereby significantly improving the corrosion resistance of the coatings. Particularly, Zn-Al-Mg-Re with 0.15% (mass fraction) La exhibits the best corrosion resistance among the tested galvanizing coatings.

Zinc-aluminum-magnesium (Zn-Al-Mg) coatings doped with rare earths lanthanum (La) and cerium (Ce) (denoted as Zn-Al-Mg-Re) have been prepared on Q345 steel substrate by hot-dip galvanizing so as to improve the corrosion resistance of the transmission towers, and to understand the corrosion inhibition of the Zn-Al-Mg-Re coating.

The purpose of this paper is to model the paths of risks associated with building information modeling (BIM) adoption in the Chinese architecture, engineering and construction industry.

A total of 16 risks were identified from the literature review and grouped into nine categories. The data were collected through a questionnaire survey with 95 professionals in China. The partial least square structural equation modeling was used to analyze the data.

The results suggested the risk categorization was confirmed, and that 15 hypothetical risk paths were statistically significant, which formed 13 chains of risk paths. “Inadequate relevant knowledge and expertise” was the primary root risk category of all the 13 chains of risk paths. Additionally, “technological issues,” “poor information sharing and collaboration,” and “liability for data input” had direct effect on the “cost overrun with BIM,” while all the other risks indirectly influence cost via these three risk categories.

Most of the respondents were designers because few clients and contractors have adopted BIM. In addition, the impact and likelihood of risks were accessed by respondents’ judgment based on their experience, which is a common problem of risk management research. As this study focuses on the Chinese architecture, engineering and construction industry, there would be geographical limitation on the findings.

This study provides practitioners with a clear understanding of the risks associated with BIM adoption and enables practitioners to take measures to mitigate the root risks and assure the potential benefits of BIM.

Although there have been studies on the risks associated with BIM adoption, most of them lacked empirical evidence and failed to examine the interactions between risks. This study is different from these prior studies, because it focuses on the interrelationships between risks and identifies the risk paths and root risks using the empirical data. Therefore, this study expands the literature relating to both BIM and risk management. Also, this study enables practitioners to take measures to mitigate the root risks and assure the potential benefits produced by BIM, thereby contributing to the practice.