Robot manipulators are playing increasingly significant roles in scientific researches and engineering applications in recent years. Using manipulators to save labors and increase accuracies are ...becoming common practices in industry. Neural networks, which feature high-speed parallel distributed processing, and can be readily implemented by hardware, have been recognized as a powerful tool for real-time processing and successfully applied widely in various control systems. Particularly, using neural networks for the control of robot manipulators have attracted much attention and various related schemes and methods have been proposed and investigated. In this paper, we make a review of research progress about controlling manipulators by means of neural networks. The problem foundation of manipulator control and the theoretical ideas on using neural network to solve this problem are first analyzed and then the latest progresses on this topic in recent years are described and reviewed in detail. Finally, toward practical applications, some potential directions possibly deserving investigation in controlling manipulators by neural networks are pointed out and discussed.
This paper considers cooperative kinematic control of multiple manipulators using distributed recurrent neural networks and provides a tractable way to extend existing results on individual ...manipulator control using recurrent neural networks to the scenario with the coordination of multiple manipulators. The problem is formulated as a constrained game, where energy consumptions for each manipulator, saturations of control input, and the topological constraints imposed by the communication graph are considered. An implicit form of the Nash equilibrium for the game is obtained by converting the problem into its dual space. Then, a distributed dynamic controller based on recurrent neural networks is devised to drive the system toward the desired Nash equilibrium to seek the optimal solution of the cooperative control. Global stability and solution optimality of the proposed neural networks are proved in the theory. Simulations demonstrate the effectiveness of the proposed method.
Gender differences in life satisfaction (LS) have been studied for a long time, and the first meta-analysis on this issue was conducted almost 40 years ago. Since then, the social status of females ...has changed considerably across different nations and cultures. The individual studies in this area continued to show inconsistent results concerning gender group differences in their respective perception of LS. In this study, 46 empirical studies from 1980 to 2017 (with a cumulated total N = 11,772) were meta-analyzed to examine potential gender differences in LS among children and adolescents, and to explore if some study features could be moderators that could account for the observed inconsistencies in the findings across studies. The findings revealed that LS remains invariant across gender groups, but with a slight difference in favor of male children and adolescents. Our results further suggested that four study features were shown to contribute to the variations of the reported gender difference in LS across individual studies: geographical region, population type, age, and domain specific LS measurements. Such different features across the individual studies could have led to the observed inconsistency of the findings. Understanding how gender differences in LS vary by these study features could allow us to consider more targeted support to increase LS of children and adolescents in different situations.
Purpose
As a 12-item Short Form of the Eating Disorder Examination Questionnaire (EDE-QS), the EDE-QS was developed based on Rasch modeling to address certain weaknesses of the EDE-Q, and it has been ...demonstrated to be a psychometrically sound measure. Thus, the current study aimed to obtain a Chinese version of the EDE-QS and validate its psychometric properties in the Chinese context.
Methods
According to standard procedures, the Chinese version of the EDE-QS (C-EDE-QS) was obtained. A total of 1068 Chinese college students finished the survey. The psychometric properties of the C-EDE-QS were examined under the frameworks of both classic test theory and Rasch modeling.
Results
The one-factor structure of the C-EDE-QS was confirmed in confirmatory factor analysis; the C-EDE-QS showed good reliability with a Cronbach’s
α
of 0.89; and the total scores of the C-EDE-QS were significantly correlated with eating disturbances and psychological distress in expected magnitudes and directions. Rasch analysis supported the unidimensional construct of the C-EDE-QS and the four-point rating scale structure. However, results revealed differential item functioning (DIF) across gender groups.
Conclusions
The findings suggest that the C-EDE-QS could be a useful tool to assess key attitudes and behavioral features of eating disorder psychopathologies in the Chinese context.
Level of evidence
V, descriptive (cross-sectional) study.
Purpose
The aim of this study was to provide preliminary psychometric evidence for the Chinese version of the Inflexible Eating Questionnaire (C-IEQ) among a large sample of Chinese adolescents.
...Methods
For testing the psychometric properties of the C-IEQ, a total of 2241 (
M
age
= 13.91 years; 46.4% boys) adolescents from mainland China responded to the survey. Confirmatory factor analysis (CFA) was used to examine the factor structure of the C-IEQ. Measurement invariance by gender was examined by both multi-group CFA and differential item functioning (DIF). Convergent validity of the C-IEQ was assessed via examining the correlations between the C-IEQ scores and theoretically related constructs (e.g., orthorexia nervosa symptomatology, eating disorder symptomatology, and body image inflexibility).
Results
The unidimensional structure with correlated errors of the C-IEQ showed good model fit (
χ
2
= 1674.05,
df
= 44,
p
< 0.001; CFI = 0.93; TLI = 0.91; RMSEA = 0.13; SRMR = 0.06). The C-IEQ had an adequate internal consistency (
α
= 0.89) and demonstrated strong measurement invariance across genders. Moreover, the scores of the C-IEQ showed significant correlations with theoretically correlated constructs: orthorexia nervosa symptomatology (girls;
r
= 0.53
p
< 0.001, boys;
r
= 0.45
p
< 0.001), eating disorder symptomatology (girls;
r
= 0.32
p
< 0.001, boys;
r
= 0.25
p
< 0.001) body image inflexibility (girls;
r
= 0.41
p
< 0.001, boys;
r
= 0.36
p
< 0.001), suggesting good convergent validity of the C-IEQ.
Conclusion
The C-IEQ showed good psychometric properties in a sample of Chinese adolescents and can be used in future studies to assess eating-specific psychological inflexibility among Chinese adolescents.
Level of evidence
Level V, cross-sectional descriptive study.
Despite numerous studies involving personality traits and second language (L2) learning achievement over many years, there is a lack of an overall picture about how personality traits are related to ...L2 learning achievement. This study aims to conduct a systematic quantitative synthesis of the studies that examined the relationships between the Big Five personality traits and L2 learning achievement. A total of 137 correlation coefficients from 31 primary studies conducted in 24 countries, with a total cumulative sample size of 8853 and published between 1982 and 2020, were included in this synthesis. The findings showed that openness to experience (
r
= .23; 95% CI: .15, .30;
p
< .001), conscientiousness (
r
= .18; 95% CI: .08, .28;
p
= .002), extraversion (
r
= .12; 95% CI: .02, .21;
p
= .017), and agreeableness (
r
= .10; 95% CI: .01, .18;
p
= .025) had positive correlations with L2 learning achievement, while neuroticism (
r
= − .04; 95% CI: − .09, .02;
p
= .227) had a negative yet statistically non-significant correlation with L2 learning achievement. More specifically, openness to experience and conscientiousness were the stronger correlates with L2 learning achievement, followed by more moderate correlates of extraversion and agreeableness, while neuroticism was the weakest among the five. Furthermore, several study features (i.e., study region, age of participants, L1 and L2 similarities, and schooling levels) were shown to explain the variations in the relationships between the Big Five personality traits and L2 learning achievement across individual studies. Implications for L2 teaching and future research are discussed.
Previous empirical studies on the effect of scaffolding in game-based learning environments have shown inconsistent findings. In this study, we conducted a meta-analysis to examine the effect of ...scaffolding in digital game-based learning (DGBL) and to explore a range of moderating factors that may have contributed to the inconsistencies of primary studies. We used the three-level meta-analysis method to analyze the data for handling data non-dependency issues of multiple effect sizes in one study. A total of 49 primary studies and 154 effect sizes were identified through systematic literature search. The results show that scaffolding in DGBL could effectively improve learning (
g
= 0.43, 95% CI: 0.30, 0.56), and the heterogeneity among studies was significant (
Q
= 708.99,
p
< 0.001). Furthermore, our results indicate that the studies involving elementary school students and university students showed larger effect sizes of scaffolding than those involving secondary school students. Scaffolding also appeared to be differentially effective in different types of games: more effective in adventure, puzzle, and simulation games than in role-playing and strategy games. Future studies should pay attention to the design of scaffolding mechanisms in educational digital games and to the influence of scaffolding on behavioral patterns and learning processes of learners engaged in DGBL.
The current study examined the roles of weight-related teasing in the relationship between body weight (body mass index, BMI) and body dissatisfaction in boys and girls. Participants were 711 ...adolescents recruited from secondary schools in China. They completed self-report questionnaires designed to assess weight-related teasing and body dissatisfaction. Participants’ BMIs were derived from their measured weights and heights. Weight-related teasing was found to play two roles in the relationship between body weight and body dissatisfaction. Specifically, weight-related teasing mediated the path from BMI to body dissatisfaction partially in girls and fully in boys. Weight-related teasing had a moderating effect on the relationship between BMI and body dissatisfaction in girls; this moderating effect was not significant in boys. Adolescents with higher BMIs tend to have higher levels of body dissatisfaction, and this association may be mediated and moderated by weight-related teasing. Interventions targeting body dissatisfaction among overweight and obese adolescents could be attentive to weight-related teasing.
Purpose
As there is no measure available in Chinese for assessing orthorexia nervosa (ON), and as the Düsseldorf Orthorexia Scale (DOS) has demonstrated to be a valid measure for such a purpose, the ...current study aimed to obtain a Chinese version of the DOS (C-DOS), to evaluate psychometric properties of the C-DOS in a sample of Chinese university students, and to explore the prevalence of ON among the participants.
Methods
According to standard procedures, the C-DOS was obtained and administered to 1075 mainland Chinese university students (52.7% female) recruited from two provinces in mainland China. To examine the factor structure of the C-DOS, the total sample was split into two halves, one for exploratory factor analysis, and the other for confirmatory factor analysis. The ordinal alpha and test–retest reliability were examined. Convergent and divergent validity was assessed by conducting Pearson correlation analyses between the C-DOS and other theoretically related/unrelated measures. Prevalence of ON was estimated based on the total score of the C-DOS with the cutoff value of 30.
Results
A three-factor structure was revealed for the C-DOS. The C-DOS showed good internal consistency with an ordinal alpha of 0.80, and it also had good test–retest reliability of 0.77. The total scores of the C-DOS had strong and statistically significant positive correlations with eating inflexibility, while the total scores had weak correlations with other eating disturbances. Strong measurement invariance across gender groups was also supported. The prevalence of ON was 7.8% with males showing higher rates of ON than females (10.6% vs. 5.3%).
Conclusions
The Chinese version of the DOS (C-DOS) was psychometrically adequate for the sample of Chinese students. Given the high prevalence of ON found in the current study, more attention to ON, as well as further research and potential interventions, are warranted in China.
Level of evidence
Descriptive (cross-sectional) study, Level V.
