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Because of the key role of joint torque in industrial robots (IRs) motion performance control and energy consumption calculation and efficiency optimization, the purpose of this paper is to propose a deep learning torque prediction method based on long short-term memory (LSTM) recurrent neural networks optimized by particle swarm optimization (PSO), which can accurately predict the the joint torque.

The proposed model optimized the LSTM with PSO algorithm to accurately predict the IRs joint torque. The authors design an excitation trajectory for ABB 1600–10/145 experimental robot and collect its relative dynamic data. The LSTM model was trained with the experimental data, and PSO was used to find optimal number of LSTM nodes and learning rate, then a torque prediction model is established based on PSO-LSTM deep learning method. The novel model is used to predict the robot’s six joint torque and the root mean error squares of the predicted data together with least squares (LS) method were comparably studied.

The predicted joint torque value by PSO-LSTM deep learning approach is highly overlapped with those from real experiment robot, and the error is quite small. The average square error between the predicted joint torque data and experiment data is 2.31 N.m smaller than that with the LS method. The accuracy of the novel PSO-LSTM learning method for joint torque prediction of IR is proved.

PSO and LSTM model are deeply integrated for the first time to predict the joint torque of IR and the prediction accuracy is verified.

The purpose of this paper is to verify the influence of superplasticizer and air entrainment admixtures (AEs) in the electrical resistivity of concrete.

Ten different types of concrete have been studied. Three levels of superplasticizer and air AEs have been used (0.20, 0.35 and 0.50 per cent). Concrete samples were cast and the electrical resistivity was monitored at the ages of 28, 63 and 91 days. Compressive strength and density tests have also been executed.

The superplasticizer admixture presented an optimal level of 0.35 per cent that significantly increased the electrical resistivity. The air AEs at the same dosage caused a considerable decrease in the electrical resistivity. The concrete with air AEs showed highest resistivity/MPa ratio.

The results should be carefully extrapolated for other materials and admixtures.

The usage of chemicals admixture in concrete is extremely common nowadays. However, only a few authors have studied the impact of such materials on the concrete’s electrical resistivity. Since many other researchers have already correlated electrical resistivity with other concrete’s properties, such as strength, setting time and corrosion probability, it is important to better understand how superplasticizers and air-entraining agents, for instance, impact the resistivity.

The vast majority of studies only tested the resistivity of cement paste or mortar and usually for short period of time (up to 28 days), which seems not to be adequate since the cement reaction continues after that period. This paper fills this gap and studied the impact of admixture on concrete and for a period of 91 days.

The purpose of this paper is to perform the thermo-hydro-mechanical (THM) numerical analysis in order to study the thawing process for frozen soil and to predict the thawing settlement.

A new one-dimensional multi-field physical coupled model was proposed here to describe the thawing process of saturated frozen soil, whereby the void ratio varied linearly with effective stress (Eq. 10) and hydraulic conductivity (Eq. 27b). The thawing process was simulated with different initial and boundary conditions in an open system with temperature variations. The mechanical behavior and water migration of the representative cases were also investigated.

The comparisons of representative cases with experimental data demonstrated that the model predicts thawing settlement well. It was found that the larger temperature gradient, higher overburden pressure and higher water content could lead to larger thawing settlement. The temperature was observed that to distribute height linearly in both frozen zone and unfrozen zone of the sample. Water migration forced to a decrease in the water content of the unfrozen zone and an increase in water content at the thawing front.

In this study, only the one-directional thawing processes along the frozen soil samples were investigated numerically and compared with test results, which can be extended to two-dimensional analysis of thawing process in frozen soil.

This study helps to understand the thawing process of frozen soil by coupled thermo-hydro-mechanical numerical simulation.

Many historical urban cultural landscapes are suffering the effect of rapid urban economic development. This paper integrally relates historical sites in dispersed and point-shape distributions in cities and proposes strategies and methods for constructing urban linear cultural landscapes. As such, our work aims to form urban cultural landscape communities with an organic and linear distribution. The urban linear cultural landscape is not only an important means for integrally protecting and utilizing historical sites in historical cities but is also a special type of urban cultural landscape. The urban linear cultural landscape’s extensive application can enrich the theory of cultural landscape and protection methods of urban cultural heritage.

In this study, the authors argue that because of female traits, the proportion of female directors in the board helps the governing body make more cautious decisions, thus improving the investment efficiency of the firm. Therefore, this research aims to propose the mediating role of caution in reexamining the relationship between the proportion of female directors and the efficiency of the investment of a firm.

This study uses data on 100 nonfinancial listed firms in Malaysia between 2015 and 2018. The authors use several multivariate regression analyses to test the mediating effect.

The result shows that female directors significantly affect investment efficiency. Moreover, the findings in this research confirm the mediating role of caution in the relationship between the proportion of female directors and the efficiency of firm investment.

This study proves that increasing the proportion of females in the board of directors is an effective governance method to improve the investment efficiency of listed firms in Malaysia.

In general, this study contributes to the literature by extending the current understanding of risk propensity differences between male and female directors and introducing the concept of caution.

Resin-based friction materials are the most widely used key materials in industry for braking and transmission. However, the friction coefficient of resin-based friction materials significantly decreases at temperatures above 300°C, which reduces their friction performance.

This study combines elevated-temperature mechanical experiments with friction and wear experiments to explain the thermal degradation resistance performance and temperature recovery performance of resin-based friction materials. It also investigates the influence of friction material strength and worn morphology on the friction coefficient of materials at elevated temperature.

The experimental results show that the increase in friction coefficient of friction materials below 300°C is mainly due to the increase in worn morphology characterization parameters, and the thermal degradation phenomenon above 300°C is mainly due to the decrease of shear strength of friction film. Basalt fiber can significantly improve the thermal degradation resistance of friction materials. The friction coefficient of basalt fiber-reinforced specimens after thermal degradation reaches 0.421–0.443, which is 19–25% higher than the original. The thermal decay rate is 9.03–11.0%, which is 7.9–9.87% lower than the original. Moreover, the friction coefficient has good cooling recovery performance.

Revealed the thermal degradation mechanism of resin-based friction materials, verified that basalt fibers can improve the thermal degradation resistance of friction materials and provided reference for the development of new friction materials.

This paper aims to report on a study that used the practice theory lens to understand how Chinese ethnic culture influences restaurant workers' learning through engagement in everyday work practices.

A multiple case study approach was used. Data were collected from semi-structured interviews and site observations. Thematic analysis was conducted to identify how workers learnt the sayings, doings and relatings in their workplaces.

The findings show that the ethnic culture of the participants influences and enriches their learning in practice settings such as small Chinese restaurants.

The understandings presented here need to be verified through more research in different regions and nations. In addition, cross-cultural studies on other ethnic restaurants may contribute to deeper understandings of the influences of ethnic culture on practice-based learning.

The research contributes to understanding the influence of ethnic culture on practice-based learning.

The understandings gained from the findings of this study form a useful basis for curriculum development and instructional design of training programmes for practice-based as well as work-integrated-learning components of vocational curriculum. Furthermore, awareness of the strengths of the ethnic culture is of interest to owner/managers of small Chinese restaurants to afford supportive learning environments for workers.

The primary objectives of this article are to systematically explore whether and how certain WeChat use motives could lead to bridging social capital, bonding social capital and civic engagement among young people.

The data was collected from a large-scale online survey of 1208 young people in mainland China. Zero-order correlation analyses and structural equation modeling were carried out to examine the corresponding hypotheses.

Obtained findings show that WeChat use for informational and social motivations are positively associated with bonding and bridging social capital. Moreover, bonding social capital could mediate the relationship between WeChat usage for informational and relational motivations and civic engagement.

Theoretically, this article underlines the unique social and technological affordances of WeChat by exploring mobile social media use and how it would contribute to the quality of democracy by fostering young people's engagement in civic life. Practically, bridging and bonding social capital play significant roles in enhancing young people's civic engagement, which could be the meaningful resource for mobile social media designers, managers and government officials.

These obtained outcomes underlined the vital role of these newly emerging communication technologies in fostering democratic involvement and production of social capital in contemporary socially networked society.

The purpose of this paper is to introduce a co‐simulation method to study the ground maneuvers of aircraft anti‐skid braking and steering.

A virtual prototype of aircraft is established in the multibody system dynamics software MSC.ADAMS/Aircraft. The anti‐skid braking control model, which adopts the multi‐threshold PID control method with a slip‐velocity‐controlled, pressure‐bias‐modulated (PBM) system, is established in MATLAB/Simulink. EASY5 is used to establish the hydraulic system of nose wheel steering. The ADAMS model is connected to block diagrams of the anti‐skid braking control model in MATLAB/Simulink, and is also connected to the block diagrams of nose wheel steering system model in EASY5, so that the ground maneuvers of aircraft anti‐skid braking and steering are simulated separately.

Results are presented to investigate the performance of anti‐skid braking system in aircraft anti‐skid simulation. In aircraft steering simulation, the influence of two important parameters on the forces acting on the tires is discussed in detail, and the safe area to prevent aircraft sideslip is obtained.

This paper presents an advanced method to study the ground maneuvers of aircraft anti‐skid braking and steering, and establishes an integrated aircraft model of airframe, landing gear, steering system, and anti‐skid braking system to investigate the interaction of each subsystem via simulation.

In today’s digital era, data pertaining to scientific research have attracted considerable attention of researchers. Data of scientific publications can be modeled in the form of networks such as citation networks, co-citation networks, collaboration networks, and others. Identification and ranking of important nodes in such networks is useful in many applications, such as finding most influential papers, most productive researchers, pattern of citation, and many more. The paper aims to discuss this issue.

A number of methods are available in literature for node ranking, and K-shell decomposition is one such method. This method categorizes nodes in different groups based on their topological position. The shell number of a node provides useful insights about the node’s importance in the network. It has been found that shells produced by the K-shell method need to be further refined to quantify the influence of the nodes aptly. In this work, a method has been developed, which ranks nodes by taking the core(s) as the origin and second-order neighborhood of a node as its immediate sphere of influence.

It is found that the performance of the proposed technique is either comparable or better than other methods in terms of correctness and accuracy. In case of assigning different ranks to nodes, the performance of the proposed technique is far more superior to existing methods. The proposed method can be used to rank authors, research articles, and fields of research.

The proposed method ranks nodes by their global position in a network as well as their local sphere of information. It leads to better quantification of a node’s impact. This method is found to be better in terms of accuracy and correctness. In case of assigning different ranks to nodes, the performance of the proposed technique is far more superior to existing methods.