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Variable stiffness structure can significantly improve the interactive capabilities of grippers. Shape memory alloys have become a popular option for materials with variable stiffness structures. However, its variable stiffness range is limited by its stiffness in two phases. The purpose of this paper is to enhance the manipulation capabilities of tendon-driven flexible grippers by designing a wide-range variable stiffness structure.

Constitutive models of shape memory alloy and mechanical models are used to analyze the performance of the variable stiffness structure. A separated solution was used to combine the tendon-driven gripper and the variable stiffness structure. The feed-forward control algorithm is used to enhance the control stability of the variable stiffness structure.

The stiffness variable capability of the proposed variable stiffness structure is verified by experiments. The stability of the feedback control algorithm was verified by sinusoidal tracking experiments. The variable stiffness range of 8.41 times of the flexible gripper was tested experimentally. The interaction capability of the variable stiffness flexible gripper is verified by the object grasping experiments.

A new wide-range variable stiffness structure is proposed and validated. The new variable stiffness structure has a larger range of stiffness variation and better control stability. The new flexible structure can be applied to conventional grippers to help them gain stiffness variable capability and improve their interaction ability.

This paper aims to present a natural human–robot teleoperation system, which capitalizes on the latest advancements of monocular human pose estimation to simplify scenario requirements on heterogeneous robot arm teleoperation.

Several optimizations in the joint extraction process are carried on to better balance the performance of the pose estimation network. To bridge the gap between human joint pose in Cartesian space and heterogeneous robot joint angle pose in Radian space, a routinized mapping procedure is proposed.

The effectiveness of the developed methods on joint extraction is verified via qualitative and quantitative experiments. The teleoperation experiments on different robots validate the feasibility of the system controlling.

The proposed system provides an intuitive and efficient human–robot teleoperation method with low-cost devices. It also enhances the controllability and flexibility of robot arms by releasing human operator from motion constraints, paving a new way for effective robot teleoperation.

This paper aims to establish the relationship between crosswind speed and pantograph-catenary lateral deviation, as well as quantify the influence of crosswind speed and rod size uncertainty on pantograph-catenary contact reliability.

The closed vector method is used to establish the pantograph-catenary kinematics formula. A new prediction model is proposed by using the bird swarm algorithm to optimize the grey model. The lateral deviation of the pantograph and catenary is predicted via the new model. Then the relationship between the effective length of the rod and operating mileage is inferred by combining the effective length theory with the Gamma process, as well as the pantograph-catenary contact reliability model is established according to reliability theory.

The results obtained show the impacts of uncertainty design parameters of pantograph rods on pantograph-catenary contact reliability index, and the results at crosswind speed of 0 ms⁻¹ and 5 ms⁻¹ are 5.0630 and 4.1442, respectively. The reliability decreases with the increasing crosswind speed, and can be greater than the reliability calculated for rod size degradation due to long-term use.

Most preceding works on pantograph-catenary contact reliability were based on principles of dynamics, without considering the pantograph-catenary relative motion. This research reveals the law of pantograph-catenary relative motion for uncertainty design parameters and crosswind, and quantifies the reliability from the angle of kinematics.

This paper aims to propose an intuitive shared control strategy to control a humanoid manipulator that can fully combine the advantages of humans and machines to produce a stronger intelligent form.

The working space of an operator’s arm and that of a manipulator are matched, and a genetic algorithm that limits the position of the manipulator’s elbow joint is used to find the optimal solution. Then, the mapping of the operator’s action to that of manipulators is realized. The controls of the human and robot are integrated. First, the current action of the operator is input. Second, the target object is predicted according to the maximum entropy hypothesis. Third, the joint angle of the manipulator is interpolated based on time. Finally, the confidence and weight of the current moment are calculated.

The modified weight adjustment method is the optimal way to adjust the weight during the task. In terms of time and accuracy, the experimental results of single target obstacle avoidance grabbing and multi-target predictive grabbing show that the shared control mode can provide full play to the advantages of humans and robots to accomplish the target task faster and more accurately than the control merely by a human or robot on its own.

A flexible and highly anthropomorphic human–robot action mapping method is proposed, which provides operator decisions in the shared control process. The shared control between human and the robot is realized, and it enhances the rapidity and intelligence, paving a new way for a novel human–robot collaboration.

In the textile industry, liquid ammonia treatment is an important way to modify the structure of natural fibers. The purpose of this paper is to reveal the diffusion behaviors of liquid ammonia in cellulose.

To analysis the diffusion behaviors of liquid ammonia in cellulose, the cellulose model and the system of ammonia and cellulose are built. Infrared spectrum is carried out to test the model of cellulose, which is found to agree with experiment. Diffusion coefficients, free volume and hydrogen bonds are discussed to explain diffusion behaviors.

The results demonstrate that diffusion coefficients and free volume of systems rise with increasing temperature. The diffusion coefficients of ammonia are larger than those of water, a result in agreement with free volume. To understand the mechanism of diffusion, the numbers of hydrogen bonds are tracked. It is found that without ammonia, intrachain hydrogen bonds decrease with the increase of temperature, which indicate that the structural stability of cellulose is deteriorated. And the increased interchain hydrogen bonds show that swelling properties of cellulose become better with the increase of temperature. After ammonia treatment, the numbers of intrachain hydrogen bonds remain stable, indicating that the structure stability of cellulose chain is maintained. But, there is a substantial rupture of interchain hydrogen bonds, ammonia molecule destroys the hydrogen bond network between the original cellulose molecular chains, which intensifies the activity of cellulose molecular chains and enlarges the distance between cellulose molecular chains, showing good swelling properties.

The research findings give a detailed information about the diffusion behaviors of liquid ammonia in cellulose, which provide the theoretical evidence for liquid ammonia treatment.

The purpose of this paper is to study a fractional grey model FAGM(1,1,t^α) based on the GM(1,1,t^α) model and the fractional accumulated generating operation, and then predict the national health expenditure, the government health expenditure and the out-of-pocket health expenditure of China.

The presented univariate grey model is systematically studied by using the grey modelling technique, the fractional accumulated generating operation and the trapezoid approximation formula of definite integral. The optimal system parameters r and α are evaluated by the particle swarm optimisation algorithm.

The expressions of the time response function and the restored values of this model are derived. The GM(1,1), NGM(1,1,k,c) and GM(1,1,t^α) models are particular cases of the FAGM(1,1,t^α) model with deterministic r and α. Compared with other forecasting models, the results of the FAGM(1,1,t^α) model have higher precision.

The superiority of the new model has high potential to be used in the medicine and health fields and others. Results can provide a guideline for government decision making.

The univariate fractional grey model FAGM (1,1,t^α) successfully studies the China’s health expenditure.

This study uses self-determination theory (SDT) to investigate the impact of limited-time deals and credit card usage on online impulse buying behavior, with a focus on hedonic motivation as a mediating variable.

A survey was conducted with 290 participants from northern India, specifically Punjab, Haryana, Delhi NCR and Chandigarh. The current analysis validates the conceptual framework using the partial least squares structural equation modeling (PLS-SEM) methodology.

The results indicate that limited-time deals and credit card usage have a favorable impact on both hedonic motivation and online impulse buying behavior. Additionally, hedonic motivation mediates the relationship between limited-time deals, credit card usage and online impulse buying behavior.

The study’s originality stems from its novel application of the SDT to investigate the effects of limited-time deals and credit card usage on online impulse buying. By exploring the mediating role of hedonic motivation, it sheds new light on the psychological dynamics of online consumer behavior.

Measuring the performance of public participation is conducive to improving participation systems. However, such measurement, particularly in urban regeneration projects, is difficult because of the complex indicators and multiple stakeholders involved. The purpose of this paper is to measure the public participation level in urban regeneration projects in China.

This study adopts a perception difference-based method to measure the public participation level in urban regeneration projects in China. Specifically, an indicator system consisting of 12 indicators from three categories was first purposed. A perception difference-based method that integrates ANOVA test and Tukey test were then developed. The method was validated using five represented projects, and the results are interpreted based on a proposed measurement matrix.

Regardless of the type of indicator, the perception of the government aligns with the perception of private sector professions, however, deviates from the perception of citizens. By taking the mean score and the significance level among stakeholders of perception as two dimensions, different patterns of issues in the current participation practice in urban regeneration are manifested.

Theoretically, the proposed indicator system and perception difference-based method combined to provide a holistic view of public participation, which is verified to provide a better measurement. Practically, the authors’ methodology helps in revealing issues in current participation practice and further leading to designing coping strategies. Nonetheless, the proposed method requires further validation in participation practices in China and other countries.

By considering the perception mean and the significance level as two dimensions, a public participation measurement matrix is proposed. The performance in different indicators are classified into four stages accordingly, namely idling, starting, running-in and accelerating.

Different aspects of the globalisation of Chinese basic education have been examined in recent studies. This paper aims to contribute to this research base by examining the relationship between global quality assurance and evaluation (QAEVAL) trends and reforms in the Chinese basic education system.

Relevant research literature in English and Chinese was reviewed to assesses whether a movement of increasing convergence with global QAEVAL policy contents and policy instruments has taken place in China following the introduction of the so-called “equality education”. A guiding theory regarding the basic features of QAEVAL was used to conceptually structure the findings of the authors.

The findings indicate that several subtle convergences are evident in China with global trends in QAEVAL, but a few notable exceptions are also evident.

Albeit the research indicates certain convergence, the authors acknowledge that further research is still needed to examine causal mechanisms of QAEVAL policy convergences and the processes and logic through which global trends are localised.

Both the importance of QAEVAL in global education governance as well as China’s importance to world affairs are increasing. However, so far, the effects of QAEVAL policies on China’s education system have not been thoroughly examined. This paper can serve as a concise starting point for examining the topic more deeply.