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The purpose of this paper is to propose a casting process for the production of double-chamber soft fingers, which avoids the problems of air leakage and fracture caused by multistep casting. This proposed method facilitates the simultaneous casting of the inflation chamber and the jamming chamber.

An integrated molding technology based on the lost wax casting method is proposed for the manufacture of double-chamber soft fingers. The solid wax core is assembled with the mold, and then liquid silicone rubber is injected into it. After cooling and solidification, the mold is stripped off and heated in boiling water, so that the solid wax core melts and precipitates, and the integrated soft finger is obtained.

The performance and fatigue tests of the soft fingers produced by the proposed method have been carried out. The results show that the manufacturing method can significantly improve the fatigue resistance and stability of the soft fingers, while also avoiding the problems such as air leakage and cracking.

The improvement of the previous multistep casting method of soft fingers is proposed, and the integrated molding manufacturing method is proposed to avoid the problems caused by secondary bonding.

The purpose of this study is to investigate the influence mechanism of different interface component surface textures on the ultrasonic motor (USM) output performance.

The energy transmission mechanism of the traveling-wave ultrasonic motor 60 (TRUM-60) was numerically and experimentally investigated by fabricating dimple textures with different feature types on the friction material and the stator.

Textured friction material can increase the contact range effectively, and thus, can improve the friction characteristics of the interface and the output performance of the TRUM-60. The experimental results verified the expected influence mechanism and demonstrated that the use of either a textured friction material or stator has a very different effect on USM output performance. A textured PI-based friction material improved the TRUM-60 output performance, resulting in a maximum energy conversion efficiency of 57.11%. However, a textured stator degraded the TRUM-60 output performance, resulting in a minimum energy conversion efficiency of only 44.92%.

The results of this study provide a theoretical foundation for improved USM designs with textured interfaces.

This paper extends our understanding of the concept and global practice of political economy.

The paper sets out the limits of conceptual analysis regarding political economy. It then applies Heidegger’s theory of metaphysics to the cultures of China and the West.

It is possible to construct an account of Confucianism metaphysics which contrasts with modern western metaphysics. The paper suggests some implications of the contrast.

The paper is exploratory and broad-brush. It suggests the potential of further systematic enquiries.

National and business leaders seek to understand the global business environment. This requires insights into the nature of culture and the foundations of cultures. The paper provides a way to make sense of national aspirations and global political/business responses to changed circumstances.

The paper continues a research programme which seeks to explicate Chinese decision-making and relate it to the western decision-making. It is the first paper to use Heidegger’s concept of metaphysics in relation to Confucianism.

In order to give full play to the function of noise reduction of asphalt pavement, it is necessary to understand its internal sound absorption mechanism. Therefore, the purpose of this study is to establish a micro model of the pore structure of asphalt mixture with the help of finite element method (FEM), discuss the noise reduction mechanism of asphalt pavement from the micro perspective and analyze and evaluate the noise attenuation law of the pore structure.

The FEM was used to establish the microscopic model of the pore structure of asphalt mixture. Based on the principle of acoustics, the noise reduction characteristics of asphalt pavement were simulated. The influence of gradation and pore characteristics on the noise reduction performance of asphalt pavement was analyzed.

The results show that the open graded friction course-13 (OGFC-13) has excellent performance in noise reduction. The resonant sound absorption structure composed of its large porosity can effectively reduce the pavement noise. For asphalt concrete-13 (AC-13) and stone matrix asphalt-13 (SMA-13), the less resonant sound absorption structure makes them have poor sound absorption effect. In addition, the variation rules of noise transmission loss (TL) curve and sound absorption coefficient curve of three graded asphalt mixtures were obtained. At the same time, the peak noise reduction values of OGFC-13, AC-13 and SMA-13 were obtained, which were 650Hz, 1000Hz and 800Hz, respectively.

The results show that the simulation results can well reflect and express the experimental results. This will provide a reference for further exploring the sound absorption mechanism and its variation rule of porous asphalt pavement. It also has some positive significance for the application of low noise asphalt pavement.

The study aims to pioneer an innovative approach for the evaluation of government portal websites (GPWs) by introducing an eye-tracking-based method. The research meticulously pinpoints and analyses the distinct usability issues and challenges that users encounter while navigating and interacting with GPWs.

This study devises an eye-tracking-based GPW usability evaluation approach, which focuses on the major functions (i.e. government information disclosure, government services and interactive responses) of GPWs. An Entropy Weighted Technique for Order Preference by Similarity to an Ideal Solution (EW-TOPSIS) method is employed to process eye-tracking indicator results for deriving GPW usability results.

The proposed approach is demonstrated to assess the usability of 12 GPWs in pilot smart cities in China, and it is found that most GPWs have lower-than-average usability. GPWs with low usability require more cognitive load that exhibit increased fixation and saccade. The comparisons among the GPW usability results from (1) the eye-tracking experiment, (2) questionnaire surveys and (3) the ready-made performance evaluation report validate the effectiveness of eye-tracking-based GPW usability evaluation.

The work contributes to shifting the GPW usability evaluation approach from a subjective judgment paradigm to an objective paradigm, as well as provides implications for enhancing GPW usability, including improving search function, reducing website complexity and prioritizing user needs.

The purpose of this paper is to develop a coated glass fiber fabric which can be used as the outer shell of firefighters' protective clothing and replace aramid fabric.

The silicone resin with excellent heat resistance was selected as the base solution. Silica nanoparticles, mica powder and ferric oxide were added into the coating solution, which was coated on the glass fiber fabrics. The vertical burning, thermal protective performance (TPP) value, second-degree burn time and water repellency of the coated fabrics were characterized.

Results showed that the dosages of the thickening filler were in the range 4%–6%; the coating solution has good viscosity. The optimal composition of fillers added in the silicone resin is silica nanoparticles 6%, ferric oxide 5% and mica powder 6%. The TPP value of the optimum coated fabric is 413 kW·s/m². The second-degree burn time is 4.98 s, which is obviously higher than that of the original glass fiber fabric (3.49 s) and that of the aramid fabric (3.82 s). The coated fabric has better thermal stability than aramid fabric.

The production cost of this coated glass fiber fabric was much lower than that of the aramid fabric.

The purpose of this study is to present a highly stretchable and flexible strain sensor with simple and low cost of fabrication process and excellent dynamic characteristics, which make it suitable for human motion monitoring under large strain and high frequency.

The strain sensor was fabricated using the rubber/latex polymer as elastic carrier and single-walled carbon nanotubes (SWCNTs)/carbon black (CB) as a synergistic conductive network. The rubber/latex polymer was pre-treated in naphtha and then soaked in SWCNTs/CB/silicon rubber composite solution. The strain sensing and other performance of the sensor were measured and human motion tracking applications were tried.

These strain sensors based on aforementioned materials display high stretchability (500 per cent), excellent flexibility, fast response (approximately 45 ms), low creep (3.1 per cent at 100 per cent strain), temperature and humidity independence, superior stability and reproducibility during approximately 5,000 stretch/release cycles. Furthermore, the authors used these composites as human motion sensors, effectively monitoring joint motion, indicating that the stretchable strain sensor based on the rubber/latex polymer and the synergetic effects of mixed SWCNTs and CB could have promising applications in flexible and wearable devices for human motion tracking.

This paper presents a low-cost and a new type of strain sensor with excellent performance that can open up new fields of applications in flexible, stretchable and wearable electronics, especially in human motion tracking applications where very large strain should be accommodated by the strain sensor.

In this paper, we present a new hybrid binary version of bat and enhanced particle swarm optimization algorithm in order to solve feature selection problems. The proposed algorithm is called Hybrid Binary Bat Enhanced Particle Swarm Optimization Algorithm (HBBEPSO). In the proposed HBBEPSO algorithm, we combine the bat algorithm with its capacity for echolocation helping explore the feature space and enhanced version of the particle swarm optimization with its ability to converge to the best global solution in the search space. In order to investigate the general performance of the proposed HBBEPSO algorithm, the proposed algorithm is compared with the original optimizers and other optimizers that have been used for feature selection in the past. A set of assessment indicators are used to evaluate and compare the different optimizers over 20 standard data sets obtained from the UCI repository. Results prove the ability of the proposed HBBEPSO algorithm to search the feature space for optimal feature combinations.

Recent years have witnessed the rapid development of massive open online courses (MOOCs). With more and more courses being produced by instructors and being participated by learners all over the world, unprecedented massive educational resources are aggregated. The educational resources include videos, subtitles, lecture notes, quizzes, etc., on the teaching side, and forum contents, Wiki, log of learning behavior, log of homework, etc., on the learning side. However, the data are both unstructured and diverse. To facilitate knowledge management and mining on MOOCs, extracting keywords from the resources is important. This paper aims to adapt the state-of-the-art techniques to MOOC settings and evaluate the effectiveness on real data. In terms of practice, this paper also tries to answer the questions for the first time that to what extend can the MOOC resources support keyword extraction models, and how many human efforts are required to make the models work well.

Based on which side generates the data, i.e instructors or learners, the data are classified to teaching resources and learning resources, respectively. The approach used on teaching resources is based on machine learning models with labels, while the approach used on learning resources is based on graph model without labels.

From the teaching resources, the methods used by the authors can accurately extract keywords with only 10 per cent labeled data. The authors find a characteristic of the data that the resources of various forms, e.g. subtitles and PPTs, should be separately considered because they have the different model ability. From the learning resources, the keywords extracted from MOOC forums are not as domain-specific as those extracted from teaching resources, but they can reflect the topics which are lively discussed in forums. Then instructors can get feedback from the indication. The authors implement two applications with the extracted keywords: generating concept map and generating learning path. The visual demos show they have the potential to improve learning efficiency when they are integrated into a real MOOC platform.

Conducting keyword extraction on MOOC resources is quite difficult because teaching resources are hard to be obtained due to copyrights. Also, getting labeled data is tough because usually expertise of the corresponding domain is required.

The experiment results support that MOOC resources are good enough for building models of keyword extraction, and an acceptable balance between human efforts and model accuracy can be achieved.

This paper presents a pioneer study on keyword extraction on MOOC resources and obtains some new findings.

A mesoscopic phase field (PF) model is proposed to simulate the meso-failure process of lightweight concrete.

The PF damage model is applied to the meso-failure process of lightweight concrete through the ABAQUS subroutine user-defined element (UEL). And the improved staggered iteration scheme with a one-pass procedure is used to alternately solve the coupling equations.

These examples clearly show that the crack initiation of the lightweight concrete specimens mainly occurs in the ceramsite aggregates with weak strength, especially in the larger aggregates. The crack propagation paths of the specimens with the same volume fraction of light aggregates are completely different, but the crack propagation paths all pass through the ceramsite aggregates near the cracks. The results also showed that with the increase in the volume fractions of the aggregates, the slope and the peak loads of the force-deflection (F-d) curves gradually decrease, the load-bearing capacity of the lightweight concrete specimens decreases, and crack branching and coalescence are less likely during crack propagation.

The mesostructures with a mortar matrix, aggregates and an interfacial transition zone (ITZ) are generated by an automatic generation and placement program, thus incorporating the typical three-phase characteristics of lightweight concrete into the PF model.