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Affective and cognitive factors play significant roles in influencing students’ learning performance. However, limited studies exist that examine the latent interactions between these factors and students’ learning performance. This study applied a meta-analytic approach to examine the relationships between affective and cognitive factors and students’ learning performance through the selected publications. We identified 18 affective and cognitive influencing factors related to student learning achievement/performance. It was found that academic performance was significantly impacted by learning scores, future aspirations and goals, peer support for learning, and family support for learning. A moderate impact was observed for cognitive benefits, skill development, self-regulation, values, knowledge, character, self-belief, attitudes and beliefs, affective benefits, motivation, optimism, and behavioral engagement. A weak influence was observed for control and relevance of schoolwork and self-efficacy. The discussion and limitations of this study have also been provided in the last sections.

Y-Co3O4 catalysts with Y/Co molar ratio of 0.03 were prepared by several methods, such as one-step hydrothermal, two-step hydrothermal, and impregnation methods, to catalyze the decomposition of N2O. Among these catalysts, the one prepared by one-step hydrothermal method exhibited the highest activity, and then the Y-Co3O4 catalysts with various molar ratios of Y/Co were synthesized by one-step hydrothermal method. Subsequently, the optimized 0.03Y-Co3O4 was impregnated by K2CO3 solution to prepare K-modified catalyst and named as 0.02K/0.03Y-Co3O4. These catalysts were characterized by X-ray diffraction (XRD), nitrogen physisorption, hydrogen temperature-programmed reduction (H2-TPR), oxygen temperature-programmed desorption (O2-TPD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS) techniques. The results show that both Co3O4 and Y-Co3O4 exhibit spinel structure, however Y-doped Co3O4 catalysts are more active than bare Co3O4. After further modified by potassium, the 0.02K/0.03Y-Co3O4 reveals higher activity due to the more active sites (Co2+) and easier desorption of surface oxygen species than un-modified 0.03Y-Co3O4. In detail, the temperatures of N2O full conversion over 0.02K/0.03Y-Co3O4 catalyst are 325, 350, 375°C, under the reaction atmospheres of 1%N2O+Ar, 1%N2O+2%O2+Ar, 1%N2O+2%O2+8.2%H2O+Ar, respectively. In addition, over 90% conversion of N2O can be maintained at 350°C after continuous reaction for 50 h in the co-presence of oxygen and steam on K-modified Y-Co3O4 catalyst. There is a dynamic compensation effect between apparent activation energy (Ea) and pre-exponential factor (A) in N2O decomposition over Y-Co3O4 and K-modified catalysts.

With hexadecyl trimethyl ammonium bromide (CTAB) as the template, cobaltosic oxide precursors were hydrothermally synthesized. Co3O4 catalysts were then prepared by calcining the cobaltosic oxide precursors, which was further modified by impregnation with K2CO3 solution and used in the decomposition of N2O. The catalysts were characterized by means of X-ray diffraction (XRD), nitrogen physisorption, scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), hydrogen temperature-programmed reduction (H2-TPR), and oxygen temperature-programmed desorption (O2-TPD); the effect of CTAB concentration, CTAB/cobalt molar ratio and urea/cobalt molar ratio on the catalytic activity of Co3O4 was investigated. The results indicated that the Co3O4 catalyst prepared by using 0.05 mol/L CTAB solution, with a CTAB to cobalt molar ratio of 1 and a urea to cobalt molar ratio of 4, exhibits high activity in N2O decomposition. The catalytic performance of Co3O4 can be further enhanced by modifying with K. Over the 0.02K/Co3O4 catalyst, the N2O conversion remains over 91% at 400°C after conducting the N2O decomposition reaction for 50 h in the presence of oxygen and steam.

MgCo2O4 composite oxides with spinel structure were hydrothermally prepared at 120°C by using carbon sphere as template and urea as precipitant. K2CO3 solution was impregnated on MgCo2O4 and the K-modified catalyst was obtained. These catalysts were applied in catalytic decomposition of N2O and characterized by X-ray diffraction(XRD), nitrogen physisorption, scanning electron microscopy (SEM), temperature-programmed reduction of hydrogen (H2-TPR), temperature-programmed desorption of oxygen (O2-TPD), and X-ray photoelectron spectroscopy (XPS). Effect of catalysts preparation parameters such as mass ratio of cobalt and magnesium to carbon sphere, molar ratio of urea to metallic cations, on their catalytic activity was investigated. It is shown that the catalyst prepared with mass ratio 0.192 of cobalt and magnesium to carbon sphere, molar ratio 2 of urea to cobalt and magnesium cations, exhibits higher catalytic activity than others. Furthermore, 91% and 62% conversions of N2O could be reached over 0.02K/MgCo2O4 catalyst at 400°C after continuous running for 50 h under the atmosphere of oxygen-alone and oxygen-steam together, respectively, revealing that K-modified MgCo2O4 catalyst is stable under both reaction atmospheres.

Depth estimation is an active research area with the developing of stereo vision in recent years. It is one of the key technologies to resolve the large data of stereo vision communication. Now depth estimation still has some problems, such as occlusion, fuzzy edge, real-time processing, etc. Many algorithms have been proposed base on software, however the performance of the computer configurations limits the software processing speed. The other resolution is hardware design and the great developments of the digital signal processor (DSP), and application specific integrated circuit (ASIC) and field programmable gate array (FPGA) provide the opportunity of flexible applications. In this work, by analyzing the procedures of depth estimation, the proper algorithms which can be used in hardware design to execute real-time depth estimation are proposed. The different methods of calibration, matching and post-processing are analyzed based on the hardware design requirements. At last some tests for the algorithm have been analyzed. The results show that the algorithms proposed for hardware design can provide credited depth map for further view synthesis and are suitable for hardware design.