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Heavy fog results in low visibility, which increases the probability and severity of traffic crashes, and fog warning system is conducive to the reduction of crashes by conveying warning messages to drivers. This paper aims at exploring the effects of dynamic message sign (DMS) of fog warning system on driver performance.

First, a testing platform was established based on driving simulator and driver performance data under DMS were collected. The experiment route was consisted of three different zones (i.e. warning zone, transition zone and heavy fog zone), and mean speed, mean acceleration, mean jerk in the whole zone, ending speed in the warning zone and transition zone, maximum deceleration rate and mean speed reduction proportion in the transition zone and heavy fog zone were selected. Next, the one-way analysis of variance was applied to test the significant difference between the metrics. Besides, drivers’ subjective perception was also considered.

The results indicated that DMS is beneficial to reduce speed before drivers enter the heavy fog zone. Besides, when drivers enter a heavy fog zone, DMS can reduce the tension of drivers and make drivers operate more smoothly.

This paper provides a comprehensive approach for evaluating the effectiveness of the warning system in adverse conditions based on the driving simulation test platform. The method can be extended to the evaluation of vehicle-to-infrastructure technology in other special scenarios.

With the continuous improvement of public–private partnership (PPP) projects, the participants' value creation goals are not only limited to achieving the basic performance objectives but also to realising value added. However, the effect of traditional contract management on realising the value creation objectives of PPP projects is limited. According to the view of multifunctional contract, joint-contract functions that integrate contract control and flexibility are likely to be effective in enhancing the value creation of PPP projects. This study aims to explore the effects of joint-contract functions on PPP project value creation and relevant influencing mechanism by investigating the mediating effect of in-role behaviour and extra-role behaviour.

After collecting 258 valid questionnaires from PPP professionals in China, this study used structural equation modelling to validate the hypotheses.

Contract control and flexibility can improve PPP project value creation. Specifically, contract control improves the achievement of the basic contract objectives of PPP projects, whereas contract flexibility enhances the achievement of the value-added of PPP projects. Moreover, only in-role behaviour mediates the effect of contract control on value creation. In addition, the mediating effect of extra-role behaviour on the impact of contract flexibility on value creation is stronger than that of in-role behaviour. The mediating effect of in- and extra-role behaviour is mainly reflected in the realisation of basic and value-added performance, respectively.

The findings of this study can help realise value creation in three ways. Firstly, new perspectives for PPP project value creation should be proposed by combining the improvement of contract objectives and the realisation of the participants' implicit demands. Secondly, the effects of different contract functions on value creation should be analysed instead of a single dimension of contractual governance. Thirdly, the mediating effects of different types of cooperation behaviour that may influence the relationship between contractual governance and value creation should be evaluated.

This study verifies the impacts of different contract functions on PPP project value creation. In addition, cooperative behaviour is embedded as a mediating variable, and the mediated transmission path from contract function to cooperative behaviour and further to PPP project value creation is systematically analysed.

Effective performance management (PM) in public–private partnership (PPP) projects is critical to realizing value for money (VFM). This study aims to provide an in-depth understanding of problems existing in PPP PM and possible avenues for improvement, presenting an experimental system to verify that building information modeling (BIM) and other information communication technologies can improve PPP PM.

The mixed research method adopted in this study combined empirical research with experimental research. Semistructured interviews were used to ascertain the current situation of PPP PM with the help of Nvivo software. A BIM-based performance management system (BPMS), which combines BIM with Web and Cloud technology, was then constructed to achieve performance monitoring, performance measurement, and performance-based payment. Finally, a case study was introduced to explain the function application of the proposed system.

The case demonstration verified is found to verify that the developed BIM-based execution framework for PPP PM can effectively guide stakeholders toward achieving mixed PM, promote effective PM, and improve work efficiency with the support of BIM and other information and communication technologies.

Through the development of a BPMS for PPP projects, the effectiveness and efficiency of PM are improved. Practical PM applications are also provided to different stakeholders, through which the key performance indicators and the behaviors of the government and private-sector partners can be monitored to form a more comprehensive and reasonable PM mechanism and promote the realization of VFM in PPP projects.

Due to the miniaturization of electronic devices, the increased current density through solder joints leads to the occurrence of electromigration failure, thereby reducing the reliability of electronic devices. The purpose of this study is to propose a finite element-artificial neural network method for the prediction of temperature and current density of solder joints, and thus provide reference information for the reliability evaluation of solder joints.

The temperature distribution and current density distribution of the interconnect structure of electronic devices were investigated through finite element simulations. During the experimental process, the actual temperature of the solder joints was measured and was used to optimize the finite element model. A large amount of simulation data was obtained to analyze the neural network by varying the height of solder joints, the diameter of solder pads and the magnitude of current loads. The constructed neural network was trained, tested and optimized using this data.

Based on the finite element simulation results, the current is more concentrated in the corners of the solder joints, generating a significant amount of Joule heating, which leads to localized temperature rise. The constructed neural network is trained, tested and optimized using the simulation results. The ANN 1, used for predicting solder joint temperature, achieves a prediction accuracy of 96.9%, while the ANN 2, used for predicting solder joint current density, achieves a prediction accuracy of 93.4%.

The proposed method can effectively improve the estimation efficiency of temperature and current density in the packaging structure. This method prevails in the field of packaging, and other factors that affect the thermal, mechanical and electrical properties of the packaging structure can be introduced into the model.

This paper aims at fabricating large metallic components with high deposition rates, low equipment costs through wire and wire and arc additive manufacturing (WAAM) method, in order to achieve the morphology and mechanical properties of manufacturing process, a bead morphology prediction model with high precision for ideal deposition of every pass was established.

The dynamic response of the process parameters on the bead width and bead height of cold metal transfer (CMT)-based AM was analyzed. A laser profile scanner was used to continuously capture the morphology variation. A prediction model of the deposition bead morphology was established using response surface optimization. Moreover, the validity of the model was examined using 15 groups of quadratic regression analyzes.

The relative errors of the predicted bead width and height were all less than 5% compared with the experimental measurements. The model was then preliminarily used with necessary modifications, such as further considering the interlayer process parameters, to guide the fabrication of complex three-dimensional components.

The morphology prediction of WAAMed bead is a critical issue. Most research has focused on the formability and defects in CMT-based WAAM and little research on the effect of process parameters on the morphology of the deposited layer in CMT-based WAAM has been conducted. To test the sensitivities of the processing parameters to bead size, the dynamic response of key parameters was investigated. A regression model was established to guide the process parameter optimization for subsequent multi-layer or component deposition.

This research aims to explore the impact of augmented reality (AR), the digital technology that superimposes virtual elements in a real environment, on consumers in the context of experiential marketing. Specifically, this study proposes a research model based on the stimulus-organism-response model, which considers AR media characteristics as external stimuli, consumers’ value perceptions as the organisms, and purchase intentions as the responses. The research model was tested with 248 consumers using structural equation modelling. The results show that informativeness, ease of use, and telepresence have positive effects on consumers’ utilitarian value perception and that telepresence and interactivity have positive effects on hedonic value perception. Overall, this study contributes to the growing body of knowledge on AR and provides actionable insights for managers implementing digital transformation strategies and AR applications in marketing practices.

This paper aims to solve the problem of uncertain position and attitude between unstructured terrain robot and grasped target and insufficient control accuracy in extreme environment, a grasping mechanism based on attraction domain relationship is proposed, which can realize autonomous positioning, capturing and grasping of robot under low control accuracy.

The grasping mechanism was designed, taking inspiration from fishing behavior this mechanism introduces attraction domains and flexible-elastic structures through the active and passive ends to achieve automatic positioning and capture. After the capture is completed, the grasping mechanism connects the active end and the passive end, simultaneously relying on the gravity of the target object to achieve locking and release between the robot and the target object. This paper adopts theoretical, simulation and experimental verification methods to conduct theoretical and simulation analysis on the autonomous positioning and grasping process of the mechanism, and produces grasping experimental prototypes with different positions and postures.

The experiment shows that the gripping mechanism designed in this paper can achieve automatic positioning capture and gripping of large deviation situations under low control accuracy, with a displacement deviation of up to 10 mm (about 1/6 diameter of the end of the mechanism) and an angle deviation of up to 3°. The scientific research task in the extremely high altitude environment has finally been successfully accomplished.

Inspired by fishing behavior, this paper proposes a positioning, capturing and grasping mechanism. The attraction area built with permanent magnets, coupled with the flexible connection, enables precise capture under low control, while the grasping mechanism can also rely on gravity to self-lock and release.

This paper aimed to propose a novel fused-coating-based additive manufacturing (FCAM); the study of key process parameters and mechanical tests are performed to determine the proper parameters when building metal components.

Sn63Pb37 alloy is deposited in an induction heating furnace with a fused-coating nozzle to build metal parts on a copper-clad substrate. The process parameters including nozzle pressure, nozzle and substrate temperature and nozzle gap between substrate are analyzed and found to have great influence on parts quality. The mechanical property tests between the fused-coating and casting parts are performed in horizontal and vertical directions. Also, the optical microscopy images are used to ascertain under which conditions good bonding can be achieved.

A FCAM method is proposed, and the exploration study about the manufacturing process is carried out. The critical parameters are analyzed, and microscopy images prove the suitable temperature range that requires to fabricate metal parts. The mechanical tests confirm that tensile strength of printing parts is improved by 20.4 and 11.9 per cent in horizontal and vertical direction than casting parts. The experimental results indicate that there is a close relationship between process parameters and mechanical properties.

This paper proves that FCAM provides an alternative way to quickly make functional metal parts with good quality and flexibility compared with other additive manufacturing methods. Moreover, good mechanical property is achieved than conventional casting parts.

This paper aims to propose a new transformer-less inverter structure to reduce the common-mode leakage current in grid-connected photovoltaic (PV) systems.

The proposed circuit structure is the same as the conventional full-bridge inverter with three additional power switches in a triangular structure. These three power switches are between the bridge and the output filter, and they mitigate the common-mode leakage current flowing toward the PV panels’ capacitors. The common-mode leakage current mitigation is done through the three-direction clamping cell (TDCC) concept. By clamping the common-mode voltage to the middle voltage of the DC-link capacitors, the leakage current and the total harmonic distortion (THD) of the injected current to the grid is effectively reduced. Therefore, the efficiency is improved.

The switching modes and the control method are introduced. A comparison is carried out between the proposed structure and other solutions in the literature. The proposed topology and its respective control method are simulated by PSCAD/EMTDC software. The simulation results validate the advantages of the presented structure such as clamping the common-mode voltage and reducing leakage current and THD of injected current to the grid.

Presenting a single phase-improved inverter structure with low-leakage current for grid-connected PV power systems represents a significant original contribution to this work. The proposed structure can inject a sinusoidal current with low THD to the AC grid, and the power factor is unity on the AC side. In the half positive cycle, one of the switches in the TDCC is turned off under zero current. Besides, one of the other switches in TDCC is turned on with zero voltage and, therefore, its turn-on switching losses are zero. The efficiency of the proposed topology is high because of the reduction of leakage current and power losses. Accordingly, the presented topology can be a good solution to the leakage current elimination.

The purpose of this paper is to design a climbing robot connected by a connecting rod mechanism to achieve multi-functional tasks such as obstacles crossing and climbing of power transmission towers.

A connecting rod type gripper has been designed to achieve stable grasping of angle steel. Before grasping, use coordination between structures to achieve stable docking and grasping. By using the alternating movements of two claws and the middle climbing mechanism, the climbing and obstacle crossing of the angle steel were achieved.

Through a simple linkage mechanism, a climbing robot has been designed, greatly reducing the overall mass of the robot. It can also carry a load of 1 kg, and the climbing mechanism can perform stable climbing. The maximum step distance of the climbing robot is 543 mm, which can achieve the crossing of angle steel obstacles.

A transmission tower climbing mechanism was proposed by analyzing the working environment. Through the locking ability of the screw nut, stable clamping of the angle steel is achieved, and a pitch mechanism is designed to adjust the posture of the hand claw.