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The current longitudinal study examined the association of temperamental inhibition (assessed by behavioral observation and parental reports) at three years old with reward and punishment bias (measured by a spatial cueing task) and mothers' and teachers' reports of internalizing behaviors and social competence at five years old in 153 Chinese children. As predicted, behavioral inhibition positively predicted later mother-rated internalizing behaviors. In addition, punishment bias moderated this relation such that children with higher punishment bias showed a positive inhibition-internalizing link. Furthermore, inhibition negatively predicted both mother-rated and teacher-rated social competence. However, novel findings were that reward bias moderated the relation between inhibition and teacher-rated social competence, such that inhibited children showed an increased risk of low competence when they had lower reward bias.

In order to solve the difficulties in the utilization of aluminum dross resources, non-fired bricks with aluminum dross with high nitrogen concentration as the main raw material were prepared. Three process parameters, including forming pressure, mixing-water amount, and aluminum dross particle size, were subjected to single-factor experiments. Based on the response surface method, a mathematical model was established between the process parameters and the non-fired bricks' compressive properties, which were subjected to ANOVA. The process parameters were optimized and then verified experimentally. According to the results, the established regression model is able to accurately predict the compressive properties of non-fired bricks. The difference between the experimental value and the model's predicted value was only 0.36%. The optimal process parameters for aluminum dross to prepare non-fired bricks are as follows: forming pressure is 18 MPa, mixing-water amount is 15% and particle size range is 80–130 mesh. The compressive strength of the prepared non-fired bricks is 24.66 MPa, which meets the requirement of MU20 non-fired bricks in Non-fired Rubbish Gangue Bricks. [ABSTRACT FROM AUTHOR]

Aluminum dross, as a hazardous waste product, causes harm to the environment and humans, since the AlN it contains chemically reacts with water to produce ammonia. In the present study, a formula for modifying the AlN content in aluminum dross is proposed for the first time, by investigating the components of aluminum dross and changes in their respective contents during the hydrolysis process. Meanwhile, the effects of such hydrolysis parameters as time, temperature, and rotational speed on the hydrolysis rate of aluminum dross are explored. Furthermore, regression analysis is performed on the hydrolysis parameters and objective functions. The results show that as the reaction time increases, the variation in AlN content in aluminum dross decelerates gradually after modification. The hydrolysis rate is the fastest in the initial 4 h, which essentially stagnates after 20 h. The rise in temperature can significantly accelerate the AlN hydrolysis in aluminum dross, while the rotational speed has a non-obvious effect on the hydrolysis rate of AlN in aluminum dross. Regression analysis and secondary simplification are performed on the hydrolysis parameters and the modified AlN content, revealing that the relative error between the theoretical and experimental values is ≤ ±9.34%. The findings of this study have certain guiding significance for predicting and controlling modified AlN content in aluminum dross during hydrolysis. [ABSTRACT FROM AUTHOR]

Empathy, crucial to harmonious interpersonal relationships and moral development, has both affective and cognitive components. Previous studies found that toddlers' temperamental inhibition may influence their empathy, but mainly focused on emotional response to others' distress. Little is known about whether inhibited children's poor empathy is due to high reactivity and social withdrawal when sharing others' affective states, such as distress (affective empathy), or to a difficulty in comprehending and inferring others' perspective (cognitive empathy). The current study investigated the role of behavioral inhibition (BI) in affective empathy (response to pain simulation) and cognitive empathy (performance in perspective‐taking task) among 163 Chinese toddlers and tested in both only and non‐only children. Correlation analyses showed that BI was only negatively associated with affective empathy. The relation between BI and cognitive empathy was moderated by self‐regulation and inhibited children who were low in self‐regulation presented low cognitive empathy. Additionally, only children presented advanced cognitive empathy but poorer affective empathy than non‐only children. These findings imply different roles of BI in affective versus cognitive empathy in early childhood. Although highly inhibited children rarely show positive social expression toward others' distress, caution is needed in inferring that they lack a capacity for cognitive empathy. [ABSTRACT FROM AUTHOR]

Exuberance, a temperament type influenced by approach motivation, has been found to be associated with maladaptive behaviors such as more externalizing behaviors in early childhood. A possible mechanism underlying it is children's selective attention to environmental cues. However, few studies have investigated the effect of attention bias on the relation between exuberance and externalizing behaviors. This longitudinal study examined the association of temperamental exuberance (as assessed by behavioral observation and parental report) at 3 years old with attention bias to reward and punishment (as assessed by a spatial cueing task) and teachers' reports of externalizing behaviors at 5 years old in 153 Chinese preschool-age children. As predicted, externalizing behaviors were positively predicted by exuberance and attention bias to reward. However, novel findings were that attention bias to punishment moderated the relation between exuberance and externalizing behaviors, such that exuberant children showed an increased risk of externalizing behaviors when they did not have high punishment bias. The results highlight attention bias to punishment as an important factor for the development of behavioral problems in exuberant children. [ABSTRACT FROM AUTHOR]

This letter presents a new control strategy of three-phase grid-connected inverter for the positive sequence voltage recovery and negative sequence voltage reduction under asymmetrical grid faults. Unlike the conventional control strategy based on an assumption that the network impedance is mainly inductive, the proposed control strategy is more flexible and effective by considering the network impedance impact, which is of great importance for the high penetration of grid-connected renewable energy systems into low-voltage grids. The experimental tests are carried out to validate the effectiveness of the proposed solution for the flexible voltage support in a low-voltage grid, where the network impedance is mainly resistive. [ABSTRACT FROM AUTHOR]

Matrix Rectifier has evolved from the traditional three phase to three phase Matrix Converter (MC) in recent years, and inherits merits of the traditional MC. Matrix Rectifier could be divided into isolated and non-isolated two types according to using high frequency transformer or not. A kind of isolated Matrix Rectifier topology, i.e., high frequency link Matrix Rectifier (HFLMR) has been selected as the study project. Space vector modulation is the mostly focused control strategy for the HFLMR, however its algorithm and its implementation are complicated and difficulty. So a novel straightforward absolute value logic SPWM control strategy based on De-Re-coupling idea has been proposed in this paper, which could realize unit power factor and DC voltage output, and made the transformer gain volt-second balance in a high frequency switching cycle. The validity and feasibility of the proposed control strategy have been well proved by the simulation and experiment results, and a special working phenomenon named as “the dual voltage endemism” has been analyzed in detail. [ABSTRACT FROM PUBLISHER]

When matrix converter (MC) and high-frequency link (HFL) are combined together, they become more complex and gain a safe commutation for the use of high-frequency transformer. To realize energy conversion and transmission, and to achieve reliable and safe commutation at the same time are particularly important and desirable. HFL matrix converter (HFLMC) can be divided into two types: high-frequency link matrix inverter (HFLMI) and high-frequency link matrix rectifier (HFLMR). A three-phase output HFLMI is selected as the object of this study, and a novel integration sinusoidal pulse width modulation (SPWM) control strategy with one-step adaptive commutation based on De-Re-coupling idea is proposed for it. After expounding on the De-Re-coupling idea, a kind of HFLMC equivalent circuit model based on the high-frequency transformer equivalent circuit is built up. Then, a detailed analysis of the voltage stress on power devices of the HFLMC by using this model is performed. A safe operation evaluation criterion of HFLMC is also gained. A suggestion of how to select carrier wave for integration SPWM is ascertained through detail discussion, and two kinds of specific Re-coupling logic circuits are presented, and at last some experimental results are shown to make a certification for feasibility and effectiveness of the new proposed SPWM strategy. [ABSTRACT FROM AUTHOR]

Synchronization with the utility networks is crucial for operating three-phase grid-interfaced converters. A challenge of synchronization is how to fast and precisely extract the fundamental positive and negative sequences under the distorted and unbalanced conditions. Many phase-locked loop (PLL) and synchronization techniques have been presented in the past decades. Most of them make a tradeoff between the accuracy and dynamic response under severe distorted and unbalanced conditions. In this paper, a multiple-complex coefficient-filter-based PLL is presented, and its unique feature lies in the accurate and rapid extraction of the positive and negative sequence components from the polluted grid voltage, and the harmonic components can also be estimated precisely, which has the potential use for selective compensation in active filter applications. Another advantage of the proposed method is its flexibility for simplifying its structure in some specified conditions. Results of continuous-domain simulations in MATLAB and discrete-domain experiments based on a 32-b fixed-point TMS320F2812 DSP are in good agreement, which confirm the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

The secondary aluminum ash is the black slag left after the primary aluminum ash is extracted from the metal aluminum. To address the environmental pollution and resource waste caused by the accumulation and landfill of aluminum ash, this study fabricated non-fired bricks by using secondary aluminum ash as the principal raw material, which was supplemented by cement, slaked lime, gypsum and engineering sand. The effects of mix proportions of various admixtures on the mechanical properties of non-fired bricks were investigated, and on this basis, the hydration mechanism was analyzed. The results showed that the mix proportions were 68.3% aluminum ash, 11.4% cement, 6.4% slaked lime, 4.2% gypsum and 9.7% engineering sand. The compressive strength of the fabricated bricks reached 22.19 MPa, and their quality indicators were in line with the MU20 requirements for Non-fired Rubbish Gangue Bricks. Evident hydration reaction occurred inside the non-fired bricks, with main products being calcium silicate hydrate (CSH), calcium aluminate hydrate (CAH) and ettringite (AFt). Besides, a dense structure was formed, which enhanced the brick strength. [ABSTRACT FROM AUTHOR]