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Recycled aggregate self-compacting concrete (RASCC) has the potential for sustainable resource utilization and has been widely applied. Predicting the compressive strength (CS) of RASCC is challenging due to its complex composite nature and nonlinear behavior.

This study comprehensively evaluated commonly used machine learning (ML) techniques, including artificial neural networks (ANN), random trees (RT), bagging and random forests (RF) for predicting the CS of RASCC. The results indicate that RF and ANN models typically have advantages with higher R2 values, lower root mean square error (RMSE), mean square error (MSE) and mean absolute error (MAE) values.

The combination of ML and Shapley additive explanation (SHAP) interpretable algorithms provides physical rationality, allowing engineers to adjust the proportion based on parameter analysis to predict and design RASCC. The sensitivity analysis of the ML model indicates that ANN’s interpretation ability is weaker than tree-based algorithms (RT, BG and RF). ML regression technology has high accuracy, good interpretability and great potential for predicting the CS of RASCC.

ML regression technology has high accuracy, good interpretability and great potential for predicting the CS of RASCC.

This study aims to establish a multi-physics-coupled model for an electrostatic particulate matter (PM) sensor. The focus lies on investigating the deposition patterns of particles within the sensor and the variation in the regeneration temperature field.

Computational simulations were initially conducted to analyse the distribution of particles under different temperature and airflow conditions. The study investigates how particles deposit within the sensor and explores methods to expedite the combustion of deposited particles for subsequent measurements.

The results indicate that a significant portion of the particles, approximately 61.8% of the total deposited particles, accumulates on the inside of the protective cover. To facilitate rapid combustion of these deposited particles, a ceramic heater was embedded within the metal shielding layer and tightly integrated with the high-voltage electrode. Silicon nitride ceramic, selected for its high strength, elevated temperature stability and excellent thermal conductivity, enables a relatively fast heating rate, ensuring a uniform temperature field distribution. Applying 27 W power to the silicon nitride heater rapidly raises the gas flow region's temperature within the sensor head to achieve a high-temperature regeneration state. Computational results demonstrate that within 200 s of heater operation, the sensor's internal temperature can exceed 600 °C, effectively ensuring thorough combustion of the deposited particles.

This study presents a novel approach to address the challenges associated with particle deposition in electrostatic PM sensors. By integrating a ceramic heater with specific material properties, the study proposes an effective method to expedite particle combustion for enhanced sensor performance.

To address the shortcomings of the traditional back propagation (BP) neural network agent model, such as insufficient fitting accuracy and low computational efficiency, an improved method is proposed.

In this study, an improved sparrow search algorithm (ISSA) is developed to optimize the reliability calculation of the BP neural network (ISSA-BP) using an enhanced BP neural network model. The traditional sparrow search algorithm is enhanced by incorporating a golden sine strategy to improve its position-updating mechanism, thereby overcoming its tendency to converge prematurely to local optima. Additionally, an opposition-based learning strategy is integrated to explore the reverse solution around the optimal solution of the sparrow search algorithm, mitigating the risk of local optima.

The results of the test function demonstrate that the proposed method significantly enhances fitting accuracy while maintaining computational efficiency. Finally, by applying this approach to the metro bogie frame as a case study, the structural reliability of the bogie frame is evaluated using the Monte Carlo method, providing valuable insights for subsequent analysis and structural optimization.

The use of the surrogate model approach for structural reliability analysis significantly improves solution efficiency. Furthermore, the integration of ISSA with the BP neural network enhances both fitting accuracy and computational efficiency, demonstrating the superiority and practicality of the proposed method.

The adaptive performance of architects as a key professional in project delivery teams has become important for developing strategies, skills and cognitive behaviours for sustainability of working systems. However, the understanding and knowledge of adaptive performance of architects is lacking in the current literature. Thus, this study fills this gap by primarily assessing the adaptive performance of architects in project teams in project delivery.

By adopting the widely used eight-dimension attributes of adaptive performance, a questionnaire survey was conducted among team participants and stakeholders who directly or indirectly work on projects with architects in the public and private sectors project delivery supply chain in Ghana. A total of 42 responses were subsequently used in a fuzzy set theory analysis being facilitated by a set of linguistic terms.

From the assessment, the overall adaptive performance of architects from the eight-dimension attributes emerged to be fairly high. Additionally, the architects’ performance in the individual eight-dimensions showed varied results. High performance was registered in architects’ ability to handling work stress and cultural adaptability. Also, architects demonstrated a fairly high performance in dealing with uncertain or unpredictable work situations. However, in the cases of learning work tasks, technologies and procedures, interpersonal adaptability and handling crisis and emergency situations, architects were deemed to have low and fairly low adaptive performance among project teams.

Given the vagueness and complexities in understanding adaptability among teams and its assessment, through the use of fuzzy set theory based on a suitable set of linguistics terms, the study presents a novel understanding of the level of architects’ adaptive performance in project teams in project delivery. The findings are extremely useful in helping architects adapt and cope with changing competitive work environment by developing the right cognitive behaviours for task functions and organizational roles, disruptions and aiding their ability to self-regulate.

This paper aims to reveal the influence of the grooved texture parameters on the lubrication performance of circular pocket-roller pairs in cylindrical roller bearings.

In this paper, the thermal elastohydrodynamic lubrication mathematical model of the grooved texture circular pocket-roller pair was established, the finite difference method and successive over-relaxation method were used to solve the model, the influence of texture quantity, texture depth and texture area ratio on circumferential bearing capacity, friction coefficient, maximum temperature rise, stiffness and damping of the circular pocket-roller pairs were analyzed.

The results show that texture quantity, texture depth and texture area ratio significantly influence the static and dynamic characteristics of circular pocket-roller pairs. The suitable surface groove texture parameters can dramatically improve the circumferential bearing capacity, reduce the friction coefficient, inhibit the maximum temperature rise and increase the stiffness and damping of the circular pocket-roller pairs.

The research in this paper can provide a theoretical basis for the optimization design of pockets in cylindrical roller bearings to reduce friction and vibration.

Online games are widely adopted electronic applications that facilitate flow experiences, which is a highly enjoyable experience for players, thus motivating further engagement in online gameplay. During gameplay, players set gaming goals, and they must make cognitive efforts to achieve these goals. However, we do not know how goal-setting and cognitive gaming elements (game complexity and game familiarity) create flow, indicating a research gap. To fill this gap, we use the cognitive gaming elements in the literature and the theoretical elements of goal-setting theory to build a model.

Conducting a large-scale online survey, we collect 3,491 responses from online game players and use structural equation modeling for data analysis.

We find that challenging goals, game complexity, game familiarity and telepresence are positively linked to player-perceived flow, explaining 45% of the variance. The new finding is that challenging goals can strengthen the link between game complexity and flow. We also find that telepresence can strengthen the link between game familiarity and flow.

Our study provides the novel insight that gaming goals and cognitive gaming elements can generate player-perceived flow. This insight can help game makers design gaming elements to accommodate players' cognitive efforts to achieve in-game goals, thus creating flow and effectively increasing players' game engagement.

The recognition of housing as an essential requirement in enhancing the quality of life of an individual has increasingly captivated scholars’ interest, particularly within the context of sustainability. However, the identification of suitable attributes of sustainable housing to be prioritized encountered challenges due to a lack of effective approach in addressing uncertainties and stakeholders’ interests. This study attempts to identify critical attributes of sustainable housing in rural areas and explore their interrelationships.

Six dimensions and 54 criteria are proposed and validated using the expert linguistic preferences through the Fuzzy Delphi Method. The Fuzzy Decision-Making Trial Evaluation Laboratory is also applied to determine the interrelationship between those attributes.

The result demonstrates that economic benefits strongly impacted social implications for sustainable housing. The top criteria, including government participation, reduced life cycle cost, environmental protection and local authorities’ participation, are considered to assist housing stakeholders for better sustainable practices.

To the best of the authors’ knowledge, this is one of the first studies addressing the interrelationship among sustainable housing attributes through linguistic preferences in the context of rural areas.

This study aims to investigate the causal complexity of ECF investors’ peer effect through two different paths of structural social influence.

Using the fuzzy-set qualitative comparative analysis (fsQCA) approach, we employ 157 samples from a Chinese ECF source to explore how peer-effect are caused by both informational and normative mechanisms.

The findings suggests that there are multiple configurations could lead to ECF investors’ high level peer-effect through both informational and normative mechanisms, and the informational mechanism' role depends on the normative mechanism, while the normative mechanism could lead to peer-effect independently.

The findings enrich the literature on ECF investors’ behaviors by revealing the diverse configurations resulting in investors’ peer-effect and shedding new light on investigating the decision-making driven by information asymmetry and relationship settings for individuals at a disadvantage.

This is the first study that investigates the multiple-driven of ECF investors’ decision-making and the importance of mutual norms in individuals' decision-making by complex network analysis approach and qualitative comparative analysis from the perspective of complexity. The results reveal the complexity of investors’ decision-making in ECF.

Given that a prerequisite for COVID-19 transmission is the interaction between individuals, it is reasonable to suspect that transportation networks may have contributed to the spread of COVID-19. This study uses the air transportation network to quantify the risk of COVID-19 spread in the United States. The proposed model is applied at the county level and identifies the risk of importing COVID-19-infected passengers into a given county. We also undertake an examination of the factors influencing the spread of COVID-19 in relation to air travel. Utilizing an extensive dataset encompassing various socioeconomic, demographic, and healthcare-related variables, our results indicate a positive relationship between these factors and the relative risk of COVID-19 spread, highlighting the pronounced impact of population density, air travel volume, and larger household sizes on increasing travel-related risk. Conversely, greater healthcare capacity, particularly in terms of hospital and intensive care unit (ICU) beds, is associated with reduced risk. We provide estimates of expected relative risk for each county and a ranking that can be useful for informing public health policies to stem the spread of the virus by devoting resources such as screening and enhanced travel protocols to airports located in at-risk counties.

Dynamically tracking the target by unmanned ground vehicles (UGVs) plays a critical role in mobile drone recovery. This study aims to solve this challenge under diverse random disturbances, proposing a dynamic target tracking framework for UGVs based on target state estimation, trajectory prediction, and UGV control.

To mitigate the adverse effects of noise contamination in target detection, the authors use the extended Kalman filter (EKF) to improve the accuracy of locating unmanned aerial vehicles (UAVs). Furthermore, a robust motion prediction algorithm based on polynomial fitting is developed to reduce the impact of trajectory jitter caused by crosswinds, enhancing the stability of drone trajectory prediction. Regarding UGV control, a dynamic vehicle model featuring independent front and rear wheel steering is derived. Additionally, a linear time-varying model predictive control algorithm is proposed to minimize tracking errors for the UGV.

To validate the feasibility of the framework, the algorithms were deployed on the designed UGV. Experimental results demonstrate the effectiveness of the proposed dynamic tracking algorithm of UGV under random disturbances.

This paper proposes a tracking framework of UGV based on target state estimation, trajectory prediction and UGV predictive control, enabling the system to achieve dynamic tracking to the UAV under multiple disturbance conditions.