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High efficiency heat exchanger is always a hot topic, and field synergy theory is introduced as an important means to optimize the heat transfer efficiency. Based on the field synergy theory, a new type of heat exchanger is proposed in this paper, in which, the cold and hot fluid presents reverse cross flow law. Through the verification of the test and numerical simulation results, a reasonable numerical simulation model and method are obtained. Then, the flow and heat transfer conditions of the new structure heat exchanger are simulated by the verified numerical simulation technology. The conclusion is as follows: K-ε turbulence model and coupled heat transfer model can be effectively used in the numerical simulation of heat exchanger. And the reverse cross convection heat exchanger can effectively improve the uniformity of water temperature distribution in the heat exchanger.

The present study examined the psychometric properties of Student-Teacher Relationship Drawings (STRDs) to assess student-teacher relationship quality in a cross-cultural context. A sample of upper elementary school students from both the Netherlands (N = 752) and China (N = 574) was included. Results showed sufficient inter-rater reliabilities of all drawing dimensions for both the Dutch (0.68 < ICC < 0.84) and Chinese samples (0.72 < ICC < 0.85). Multiple group analyses supported partially strong invariance of STRD-dimensions across the Dutch and Chinese samples. Relationship drawing dimensions also showed moderate associations with student-reported relationship quality and engagement across both the Dutch and Chinese sample. Future cross-cultural research may therefore employ STRDs to assess students' relationship experiences.

The present study investigated (1) the mediating role of attention in the associations between children's sleep problems and classroom learning behaviors in elementary school, and (2) the moderating role of gender in these associations. Results from structural equation modeling showed that children's sleep problems had a significant and negative association with their attention level ([beta] = -0.08), and their attention level had a significant and positive association with their classroom learning behaviors ([beta] = 0.20). The indirect effect of sleep problems on classroom learning behaviors, however, was not significant ([beta] = 0.02). Gender of a child had significant moderating effects on the associations between sleep problems and attention level and between attention level and classroom learning behaviors. Related intervention programs can be implemented to reduce children's sleep problems and to improve their academic performance.

As a causal attribution, attributing academic success to giftedness might influence students' academic achievement. According to previous studies, students' self-regulated learning and negative learning emotions may mediate the association between achievement attribution and academic achievement. Therefore, the present study employed structural equation modeling to examine the association between attributing academic success to giftedness and academic achievement among elementary and secondary students, and included students' negative learning emotions and self-regulated learning as mediators. The 2018 data from China Family Panel Studies were included in the present study for analysis. Results showed that the full mediation models had satisfactory model fits. After controlling the effects of the covariates, attributing academic success to giftedness had a positive indirect association with their academic achievement, through the mediation of self-regulated learning and negative learning emotions. Based on these findings, possible explanations and suggestions for practices and future research are discussed.

Student-teacher relationship drawings were employed to investigate how students' mental representations of student-teacher relationships were affected by their gender, age, and shyness across the Netherlands and China. The sample included 752 third- to sixth-graders (48.5% boys; Mage = 9.96) from the Netherlands and 574 third- to- sixth-graders (53.7% boys; Mage = 11.48) from China. Students' drawings were double-coded on eight relationship dimensions. Multiple group models showed that Chinese students' drawings scored lower on anger/tension, role reversal, emotional distance/isolation, and global pathology but higher on vulnerability than those of Dutch students. Boys' drawings displayed higher global pathology than girls' drawings and this difference was larger in the Netherlands than in China. Other associations between student characteristics (gender, age, shyness) and drawing dimensions were equally strong across countries. As an implication, findings from Western countries may not necessarily generalize to students and teachers in Eastern countries. Drawing may be a promising method to further understand differences and similarities in the formation of student-teacher relationships across countries. [ABSTRACT FROM AUTHOR]

Due to the rapid sociocultural changes in China, Chinese parents' childrearing beliefs and practices have undergone dramatic transformations. Against this context, this study examined whether Chinese parents' endorsement of progressive and traditional childrearing beliefs would predict children's academic achievement, as well as whether parenting practices would mediate this association. This study utilized a longitudinal design and followed 206 Chinese families for 2 years from the end of preschool to Grade 2. Parents showed greater endorsement of progressive than traditional childrearing beliefs, as well as higher use of authoritative than authoritarian parenting practices. Parents' childrearing beliefs in preschool predicted children's math achievement in Grade 2 via authoritative parenting. However, parenting beliefs were unrelated to authoritarian parenting, and authoritarian parenting did not predict any of the child academic outcomes in Grade 2. The findings suggest Chinese parents' orientations toward progressive parenting beliefs and authoritative parenting practices. They also highlight the utility of parenting beliefs in explaining disparities in early academic achievement. The nonsignificant findings pertinent to authoritarian parenting call for re‐examination of the cultural meaning and effects of authoritarian parenting in Chinese society. [ABSTRACT FROM AUTHOR]

To address the problems that a single feature in radio frequency fingerprint recognition could not fully represent the integrity of the signal and that the differences between features of different classes were small, which limited the recognition accuracy, a DA-ResNeXt50 (ResNeXt50 with dense connection and ACBlock) method for radio frequency fingerprint identification based on time-frequency and bi-spectral feature fusion was proposed. Firstly, short-time Fourier transform (STFT) and bi-spectrum transform were performed separately on the signals collected from different devices, the resulting images were bi-narized and then concatenated. By taking advantage of the advantages of both transformations in the time-frequency domain and high-order statistical characteristics respectively, the radio frequency fingerprint features of different devices can be extracted and characterized more comprehensively. Then, the DA-ResNeXt50 network model was proposed. Borrowing from the idea of dense connection, each layer of the four-layer residual unit was directly connected to all previous layers, promoting feature reuse and transmission, which enabled it to better capture subtle differences between classes. Finally, the asymmetric convolution block (ACBlock) was used to replace the 3x3 convolution in the last residual unit of the model. This effectively increased the receptive field of the network and enhanced the skeleton part of the convolutional kernel, thereby improving the performance of radio frequency fingerprint recognition. The experimental results show that compared with that of using a single feature extraction method, the proposed feature fusion approach significantly improves performance. Compared with various classical models, the improved model has higher recognition accuracy. [ABSTRACT FROM AUTHOR]

Analyzing the impacts of urban landscape patterns on the thermal environment has become one of the key research areas in addressing urban heat islands (UHIs) and improving the living environment. A case study was carried out in Fuzhou, Fujian Province of China, and bi-temporal Landsat imagery was selected to calculate land surface temperature (LST), percent impervious surface area (ISA), and fractional vegetation cover (FVC). The urban area was further divided into three concentric urban zones, ranging from the city center to the urban periphery, based on urban development densities. The spatial pattern of LST and its variance were analyzed and compared between different zones and different dates. The thermal environment contribution of different zones was also quantified to indicate the change in urban landscape patterns resulting from urban expansion in different zones. Furthermore, Geodetector was used to explore the single factors and interaction factors controlling the spatial patterns of LST in each zone. The results showed that (i) urban expansion primarily increased in Zone 2 and Zone 3, and the areal proportion of high and sub-high LST areas increased from 56.11% and 21.08% to 62.03% and 32.49% in Zone 2 and Zone 3, respectively, from 2004 to 2021; (ii) the heat effect contribution of Zones 2 and 3 reached from 75.16% in 2004 to 89.40% in 2021, indicating that the increase in ISA with >LSTmean was more pronounced in Zone 3 and Zone 2 during the period; (iii) the driving factors of LST spatial distribution were regionally different because of the different landscape patterns, and the explanatory power for the heterogeneity of LST in Zone 1 was weaker than in Zone 2 and Zone 3 in the study area; (iv) the interaction of different factors had a higher explanatory power in the spatial distribution of LST than a single factor in each zone because the distributions of land cover types are heterogeneous in urban areas. The results of this study can be used to improve urban planning for urban ecology and UHI mitigation. [ABSTRACT FROM AUTHOR]

Research Findings: The present study focused on the affective quality of dyadic relationships between teachers and young children in China and the Netherlands. We examined whether there were cross-cultural differences in teachers' and children's relationship perceptions, as well as the degree to which teachers and children agreed on their relationship perceptions. The Dutch sample included 234 kindergartners and first-graders (47.7% girls; Mage = 5.82 years) and 35 teachers. The Chinese sample consisted of 190 kindergartners (50.5% girls; Mage = 5.60 years) and 19 teachers. Both teachers and children reported about their mutual relationships. Multiple group analyses showed that, unexpectedly, Chinese children experienced lower warmth and higher conflict with teachers than Dutch children. In contrast, teachers from China and the Netherlands did not differ in the degree of closeness and conflict they experienced in their relationships with young children. In both countries, teachers and children had significant agreement on conflict but lacked agreement on closeness. Practice or Policy: Thus, it seems important to include child perceptions in cross-cultural comparisons of early teacher-child relationships as well. [ABSTRACT FROM AUTHOR]