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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.

This paper aims to research the influence of pressure, friction factors, roughness and actuating speed to the mixed lubrication models of outstroke and instroke.

Mixed lubrication model is solved by finite volume method, which consists of coupled fluid mechanics, deformation mechanics and contact mechanics analyses. The influence of friction factor on the finite element model is also considered. Then, contact pressure, film thickness, friction and leakage have been studied.

It was found that the amount of leakage is sensitive to the film thickness. The larger the film thickness is, the greater the influence received from the friction factor, however, the effect of oil film on the friction is negligible. The friction is determined mainly by the contact pressure. The trend of friction and leakage influenced by actuating velocity and roughness is also obtained.

The influence of friction factor on the finite element model is considered. This can make the calculation more accurate.

The purpose of the present study is to evaluate chocolate consumption effects with a non invasive metodology. There is evidence that the consumption of dark chocolate and cocoa with high flavonoid content could have positive effects on blood pressure (BP) and weight management (WM); however, there are complications at the moment of obtaining blood samples to evaluate on children at a primary school level.

A total of 54 healthy scholars were included; consumption of 70 per cent cacao dark chocolate was integrated into the daily snack during a 30-day period. Blood pressure, body fat, total content of polyphenols in urine and total antioxidant capacity of saliva were measured. The results obtained were divided in relation of two groups of students, A and B, with lesser or higher difficulties to WM in a self-assessment test; variables were then statistically evaluated.

Consumption of chocolate produced changes in the total content of polyphenols (from 5.6 to 6.8 µg/mL, p < 0.016) and salivary antioxidant capacity [(14.76 ± 5.4 and 16.14 ± 3.9) TEU nmol versus. t = 0; p < 0.029 and p < 0.001 at 15 and 30 days, respectively]. Group B, which presented higher difficulties concerning WM, presented a body fat reduction of about 0.63 per cent after chocolate consumption (p = 0.045) and a diastolic blood pressure reduction of −2.8 mm Hg in average (p < 0.025). A significant weight gain (p < 0.023) was observed only in Group A.

Despite the reduced sensitivity of the non-invasive methodology, differences in urine and salivary content of polyphenols and antioxidant capacity suggest that the design used could be feasible, although extended studies are needed to corroborate it.

A non-invasive study for screening the potential health benefits of dark chocolate was assayed. The results suggest that dark chocolate consumption in children as part of the daily snack could be a complementary element in weight management and in prevention of future risk factors to chronic diseases.

This study aimed to investigate associations between the organisational and cultural contexts in which Chinese teachers work, the influence of these on their understandings of professionalism, and relationships between these and their perceived willingness and commitment to be effective in teaching to their best.

The research was part of a two-country collaboration between the universities of Beijing and Sydney into Australian and Chinese teachers' perceptions of influences on their professionalism in which research protocols were jointly developed and implemented. This paper focusses mainly upon the Chinese research but also refers to key differences between Australian and Chinese teachers' perspectives. Seventeen teachers in early, middle and later career phases were recruited from a convenience sample of primary and secondary schools in Beijing. Qualitative data analyses of individual interviews, and cross case comparative analyses were conducted.

The analyses of the data from Beijing indicated that almost all teachers emphasised their strong moral purposes and commitment to teach to their best, despite identifying the challenges of workload, school contexts and cultures and personal circumstances, which tested their resolve. In contrast, concerns about teacher autonomy and agency, which were common in the Australian study and other published research literature, were not highly visible in the Chinese data.

The authors acknowledge that this study was small scale and data were collected from a narrow sample from one urban region of China, and we should be cautious with the generalisability of findings to other regions and schools of China since there are significant discrepancies between developed coastal areas and large cities and the remote rural areas in China. Furthermore, interview data were only collected once, restricting insight to a snapshot in time. This research may be seen as an encouragement to researchers from other regions and countries to further explore the impact of socially situated understandings of teacher professionalism on practice. Future research could also benefit from utilising multiple data sources, longitudinal design and cross-cultural collaborations to further explore the challenge of defining teachers' understandings of professionalism locally while engaging with global perspectives.

The practical implications relate to (1) expanding conceptualisations of teacher professionalism by developing locally nuanced understandings of perceptions and enactments of professionalism in different contexts across the profession, which take account of the unique roles of national and local cultural contexts; (2) designing initial teacher education and continuing professional development programmes so that they take account of the influences on the professions' ideals and individual teacher identities, of the ideological and practical interplay in the workplace of structures such as mandated standards, and different socio-economic geographical settings (e.g. rural and urban); (3) designing leadership development programmes that take account of research on associations between school leaders' values, qualities and practices on school cultures and their effects on teachers' well-being, and capacities and capabilities to fulfil their understandings of being professionals and teach to their best.

The social implications relate to (1) further research on the associations between the effects of external policy demands on teachers' work and work–life tensions, teachers' sustained commitment and quality; and (2) further research on the impact of the collective influences of national cultures, broad-based policy conditions, personal values and the demands of particular schools, parents and students that influence teachers' experience, perceptions and enactments of professionalism in order to provide further insights into understanding the complexity of teachers' lives and promoting teachers' sustained enactments of professionalism in broad contexts.

The research findings, though tentative, revealed that the altruistic nature of their mission to serve students and the parental community was the dominant marker of professionalism for teachers in China, regardless of school structures, cultures, academic achievement imperatives and personal circumstance; and that their professionalism was informed by the socio-cultural formation of individual and collective moral responsibility, reinforced through national educational policies. These findings differed from the concerns reported by the teachers in the Australian study, which aligned with literature that suggests that teacher professionalism is being eroded through neo-liberal government policies, excessive workloads and performance-oriented cultures. Though the comparative data set is small, these findings suggest that whilst there are increasing policy convergences across nations, which seek to define teacher professionalism through their abilities to make improvements in students' measurable academic achievement, how teachers in different countries and cultures define themselves as professionals may differ.

Data has become a factor of production. This occurs when history enters the era of big data, in which technologies such as artificial intelligence, cloud computing and blockchain are used to collect, manipulate, mine and process data. Data is a special product of labor, a sub-derivative of other production factors.

The data factor has a dual attribute: being physical (technical) and social. The social attribute of the data factor can not only materialize the technical attribute but also amplify it. In other words, the data has a multiplication effect on the allocation efficiency of other production factors. The social attribute of the data is brought out via the technical attribute as the medium. From a technical perspective, this medium is strongly adhesive, and after being bonded with other factors of production, it will only lead to a physical reaction and not change the nature of other factors.

However, once these two attributes interact with each other, especially when data is combined with capital, the most adhesive factor in the market economy, a series of new social relations will then be produced based on the technical attribute, resulting in significant adjustments in social relations, involving both positive and negative externalities.

Therefore, to get a scientific understanding of the dual attribute and its interaction effects on the data factor, it is necessary to take the following steps. We should promote institutional design that amplifies the positive externality, with a focus on facilitating public data sharing and improving the value of commercial data development. Also, we need to strengthen institutional arrangements that prevent and control the negative externality by emphasizing data supervision based on data types and levels as well as the rule of law.

Karl Marx's social capital reproduction theory is his significant contribution to economics. The purpose of this paper is to review the contributions of the exploration of Chinese economists (especially Professor Liu Guoguang) in the concretization of Marx’s social capital reproduction theory combined with socialist construction since 1949.

During this process, Professor Liu Guoguang, a famous Chinese Marxist economist, has made an outstanding contribution by creating a Marxist social capital reproduction model with Chinese characteristics and a distinctive Marxist economic growth model. Professor Liu's exploration is still of crucial practical significance to building a socialist market economy today.

The process and achievements in the sinicization exploration of Marx's social capital reproduction theory were reviewed. With the reform and opening up, fundamental changes have occurred in China's economic system – the centralized planned economic system has been transformed into a socialist market economic system.

The planned management of the national economy is replaced by a macro-regulation system characterized by gross control gradually, and the concepts of agriculture, light industry, and heavy industry, and their intercorrelation are no longer applied in theory and policy. However, the sinicization exploration of Marx's social capital reproduction theory in the older generation of Marxist economists represented by Liu is not only of historical significance but also of important practical significance.

China's economic transition is essentially the process of China's institutional changes. During the changes, the appearance of institutional innovation is not regular; instead, it is intermittent and random. The purpose of this paper is to show that the fitful appearance of institutional innovation is the root of China's economic growth and fluctuations.

This paper constructs a real business cycle (RBC) model introducing the institutional factor expressed in the quantitative form under the dynamic stochastic general equilibrium (DSGE) framework by measuring China's institutional changes quantitatively.

By comparing the characteristics of the actual economic data with those of the simulated economic data, we find that this RBC model can explain 94.44%, 66.07%, 23.46%, 21.03% and 15.45% of the cyclical fluctuations in output, investment, labor, consumption and capital, respectively.

The impulse response analysis finds that the institutional shocks have a relatively long duration, lasting about 30 years, and decline slowly over time, while technological shocks decline relatively fast, lasting approximately ten years.

Trade and environment are essential issues closely related to the development of the national economy and the improvement of people’s livelihood in the new era. The Report to the 19th National Congress of the Communist Party of China (CPC) listed the construction of a strong trading power as an important part of building a modern economic system and pollution prevention and treatment as one of the three key battles to win the decisive victory of building a moderately prosperous society in all respects. However, the relationship between trade and environmental pollution is still very controversial in the existing literature, and there is a paucity of literature on the relationship between trade and environmental pollution based on micro data.

This paper merged China’s Firm-Level Pollution Database with China’s Industrial Enterprise Database and China’s industry tariff rates. Additionally, by virtue of the quasi-natural experiment of China’s accession to the World Trade Organization (WTO), a difference in difference (DID) model was constructed to alleviate the endogeneity issue.

According to the results, the trade barrier decrease (trade liberalization) significantly reduces the intensity of SO₂ emissions, a major pollutant of enterprises, as the intensity of SO₂ emissions decreased 2.16% for each unit decrease of the trade barrier. The analysis of the mechanisms shows that the SO₂ emission intensity of enterprises is mainly due to the decrease of enterprises’ pollution emission rather than the decrease of output, and the decrease of enterprises’ pollution emission is mainly caused by the enterprises’ cleaner production process rather than the end treatment of pollution emission. The decrease of coal use intensity is an important mechanism of the decrease of SO₂ emission intensity caused by the decrease of trade barriers. Among the technical effects of the change of the trade barrier affecting enterprises’ pollution emission, biased technical change rather than neutral technical change dominates.

The findings of this paper imply that expanding openness can enhance China’s social welfare not only through the economic growth mechanisms identified in the classical literature, but also through environmental improvements. This provides useful policy insights for promoting the construction of a strong trading power and winning the battle against pollution in the new era.

Starting from the theoretical mechanism of profit sharing between finance and the real economy, this paper reviews and analyzes the profitability of China's banking industry and makes a horizontal comparison with the banking industry of the United States, Japan, and Germany.

Based on the panel threshold model, it is found that there is a dual-threshold asymmetric effect between banking profit and the growth of real economy. When the net profit rate of the banking industry is lower than 0.491%, the increase in banking profitability will inhibit the growth of real economy due to profit grabbing; when the rate falls within the range of 0.491–0.801%, the increase in bank profitability is conducive to the growth of real economy.

Finance and the real economy are in the most comfortable symbiotic state; when the rate is higher than 0.801%, the continued increase in bank profitability will weaken the promotion effect of finance on the real economy, but bank profitability and the growth of real economy are still in a symbiotic state of positive promotion.

The promotion effect of China's bank profitability to the growth of real economy has shifted from the suboptimal state to the optimal range as a whole, which is attributed to the strong deleveraging and strict supervision of the Chinese government after 2016, the timely and decisive “stepping on the brakes”, pulling the financial sector back from the “illusion” caused by “self-circulated” profits and preventing it from harming the real economy.