Lithium–sulfur (Li–S) batteries have been regarded as a promising next‐generation energy storage technology for their ultrahigh theoretical energy density compared with those of the traditional ...lithium‐ion batteries. However, the practical applications of Li–S batteries are still blocked by notorious problems such as the shuttle effect and the uncontrollable growth of lithium dendrites. Recently, the rapid development of electrospinning technology provides reliable methods in preparing flexible nanofibers materials and is widely applied to Li–S batteries serving as hosts, interlayers, and separators, which are considered as a promising strategy to achieve high energy density flexible Li–S batteries. In this review, a fundamental introduction of electrospinning technology and multifarious electrospinning‐based nanofibers used in flexible Li–S batteries are presented. More importantly, crucial parameters of specific capacity, electrolyte/sulfur (E/S) ratio, sulfur loading, and cathode tap density are emphasized based on the proposed mathematic model, in which the electrospinning‐based nanofibers are used as important components in Li–S batteries to achieve high gravimetric (WG) and volume (WV) energy density of 500 Wh kg−1 and 700 Wh L−1, respectively. These systematic summaries not only provide the principles in nanofiber‐based electrode design but also propose enlightening directions for the commercialized Li–S batteries with high WG and WV.
A mathematic model is proposed using the electrospinning‐based nanofibers serve as a cathode and anode host, and separator to achieve high gravimetric (WG) and volume (WV) energy density of 500 Wh kg−1 and 700 Wh L−1 in Li–S batteries, respectively, by emphasizing the crucial parameters of specific capacity, electrolyte/sulfur (E/S) ratio, sulfur loading, and cathode tap density in the cell.
Modern technology offers many ways to enhance teaching and learning that in turn promote the development of tools for educational activities both inside and outside the classroom. Many educational ...programs using the augmented reality (AR) technology are being widely used to provide supplementary learning materials for students.
This paper describes the potential and challenges of using GeoGebra AR in mathematical studies, whereby students can view 3D geometric objects for a better understanding of their structure, and verifies the feasibility of its use based on experimental results. The GeoGebra software can be used to draw geometric objects, and 3D geometric objects can be viewed using AR software or AR applications on mobile phones or computer tablets. These could provide some of the required materials for mathematical education at high schools or universities. The use of the GeoGebra application for education in Laos will be particularly discussed in this paper.
This qualitative-ethnography study described the critical thinking skill based on indicators of interpretation, analysis, evaluation, and inference in solving mathematical problem. The subjects of ...the study were the headmaster, math teachers, and ninth grade students of a public junior high school in academic year of 2020/2021. The data were collected through observation, field notes, interview, and documentation. Triangulation of sources and technique were used to ensure the data validation in this research. Data analysis technique was done inductively with continuous process along with the data collection. The results of the study showed high initial skills in mathematics become the basic need for the students in developing critical thinking skills based on indicators of interpretation. The improvement of critical thinking based on the indicator of interpretation is accustomed through problem-based learning. Critical thinking process based on the indicator of analysis is cultivated through collaborative learning. In this indicator, the students need special attention from the teacher. There is always the possibility for every student from each level to face difficulties in solving some problems without collaborating with others. The teachers can make more effort to optimize the students’ basic holistic skills in line with their knowledge and experience in order to improve students’ critical thinking skills based on the indicator of inference. In this indicator, teachers should guide the students to improve their critical thinking skills.
Emotion management in mathematics test S. HADJI; H. MAYMOUN
Moroccan Journal of Quantitative and Qualitative Research,
07/2019, Volume:
1, Issue:
2
Journal Article
Peer reviewed
Open access
The main purpose of this study is identifying and comparing profiles of high-performing students group and lowperforming students group in terms of type of emotions reported in test context and ...frequency of using emotion management strategies mobilized. This study is based on a special methodological protocol where we selected a sample of 44 students. We used two translated, adapted and validated measuring instruments. Scale of Achievement Emotions Questionnaire for Pre- Adolescents and survey which we developed. According to statistical analysis, especially correlation coefficient, the findings show that there is a positive and significant relationship between using emotion management strategies and expression of positive emotions in mathematic test context. Besides, the data obtained by independent-samples T-test noted that high-performing students experienced positive emotions that tend to relate with effective using of emotion management strategies. However, low-performing students are expressed negative emotions; this situation is attributable to lack using these strategies.
The dynamics of students' engagement in online mathematics learning during the pandemic have been completely distinctive from face-to-face learning. To further the investigation, the current study ...aims to examine the relationship between student adaptability and engagement and the mediating role of self-regulation and grade level, parental education level, student age, and student gender. A total of 339 students, with an average age of 11.16 years, from three public elementary schools in Yogyakarta, Indonesia, participated in this study. The findings demonstrated that: 1) adaptability has a positive and significant effect on student self-regulation, 2) self-regulation has a positive and significant effect on student engagement in online mathematics learning, and 3) adaptability has a significant positive influence on student engagement in both directly and through the mediation of student self-regulation. The study has a significant implication for the student learning environment, especially parental involvement. Recommendations to encourage parental involvement for online learning engagement are made.
One area of education which has not escaped efforts to improve the Indonesian government is mathematics education. The Indonesian government must make good use of mathematics learning so that ...students can use the mathematical mindset to offset the pace of global competition. This research is an experimental research on the Process-Oriented Guided Inquiry Learning (POGIL) model on the ability of mathematical connections in terms of self-regulated learning. The design used in this study was a 2 × 3 factorial. The research sample was 179 students from 7th grade in three State Junior High Schools in Sukoharjo Regency, Central Java, Indonesia. The research sample consisted of an experimental group that subjected to the POGIL model and a control group that subjected to a direct learning model. This research instrument used was a written test and questionnaire. The data analysis technique used was a two-way ANOVA test with unbalanced cells and post hoc test. The results showed that: 1) the POGIL model produces better mathematical connection ability than the direct learning model, 2) Students with high category self-regulated learning have better mathematical connection ability than medium and low categories, and students with self-regulated learning the medium category have better mathematical connection ability than the low category.
Lateral flow assay (LFA) has found widespread applications in point-of-care diagnostics over the past decades. Its detection sensitivity is dependent on the properties of paper itself (e.g., porous ...microstructure of nitrocellulose membrane), however, the effect remains unknown. Existing mathematical models for LFA have not been proved to predict the variation trends of detection performance with different specifications of nitrocellulose membrane. To address this, we developed a mathematical model coupling the macroscopic capillary flow and the binding reaction on the internal pore surface to illustrate the complex interaction among the convection, diffusion, and binding reaction with different nitrocellulose membranes. The model was experimentally validated by implementing nucleic acid detection on LFA. The simulated results suggest that due to the trade-off between the reagent transport and the reactive surface area, there is an optimal average pore size of the nitrocellulose membrane to achieve the highest detection sensitivity. Additionally, a heterogeneous pore distribution design (i.e., smaller pore diameter at the test line region and larger pore diameter for the rest region) of the nitrocellulose membrane was proposed to provide a faster detection with improved sensitivity. The numerical model would be a practical tool for the material selection and optimization of LFA.
Mathematic connection is one of the basic abilities someone must have in order to learn mathematic successfully. Mathematic connection helps someone to understand the function of mathematics, ...improving mathematic concept, determining the correlation among mathematic concepts, and identifying the application of mathematic in the surrounding environment. The most common issue occur regarding this case is that the mathematic connection ability of mathematic pedagogy students are considerably low that finally result to low learning outcome. Moreover, mathematic learning is conducted online during the COVID-19 pandemic. Not every lecturer is capable to conduct an online learning properly. As the result, it becomes harder for the students to learn mathematic, let alone finding mathematic connection. This study aims at describing the mathematic connection ability among the mathematic pre-service teacher during online and offline learning, comparing the ability between the students who undergo online and offline learning, and creating the visualizations of mathematic connection ability of mathematic pedagogy students who undergo online learning based on their learning style. This study implements mixed methods with explanatory sequential design. The technique and data collecting instrument are conducted in two ways, those are quantitative and qualitative data collection techniques. For the quantitative data (mathematic connection ability), it is measured through test, while the qualitative data is acquired using questionnaire and descriptive qualitative according to the category of mathematic connection ability. The findings obtained are the mathematic connection ability of the students. The findings present that the mathematic connection ability of students in online learning are better than those in offline learning (expository). Students with the tendency of having more than one learning style are better than those who only prefer one type of learning style (visual, auditory, kinaesthetic).
After 25 years with small to moderate gains in performance in mathematics, scores on the National Assessment of Educational Progress (NAEP) main assessment declined between 2013 and 2015 in Grades 4 ...and 8. Previous research has suggested the decline may be linked to the implementation of the Common Core state standards. In this article, the decline in the NAEP composite score is shown to be driven primarily by losses in the content strands of Geometry and of Data Analysis, Statistics, and Probability. A gain in fractions achievement is also evident in an item-level examination of the NAEP results, but not in reported NAEP scores. These effects are discussed with respect to the CCSS, the rationale for evaluating national progress, and a potential redesign of the NAEP assessment.
•A novel separated-configured design of micro-Thermoelectric cooler (TEC) was proposed.•Mathematic model of the novelty separated structure micro-TEC was developed.•Performance of the micro-TEC ...with/without novel separated configuration was compared.•Performance analysis of the micro-TEC with separated structure in different running situation was conducted.
Owing to the physical restriction of the buildings and willingness of seeking a higher temperature difference, the hot and cold sides of a thermoelectric module often require a separation treatment, whilst the soft wire or wireless connections between the hot and cold sides can be implemented. This paper investigated a novel separated micro-thermoelectric cooler (micro-TEC) configuration for cooling, which splits the hot and cold sides of the micro-TECs for a distance, with the copper connecting wire in between. A dedicated mathematic numerical simulation for the micro-TEC was carried out. The results show that for a traditional micro-TEC, the maximum coefficient of power (COP) of the micro-TEC is 1.1923 which occurs at the current of 50 mA and temperature difference of 20 K. For the novel separated micro-TEC with connecting wires, the maximum COPs at the wire lengths of 25 μm, 50 μm, 100 μm, 200 μm are 0.9258, 0.9226, 0.9162 and 0.9035 respectively, during which current of 50 mA and temperature difference of 20 K are applied. Although the maximum COP of the micro-TEC is reduced by about 0.2, the distance between the cold and hot sides has a significant increase. Under the condition of current of 50 mA and temperature difference of 20 K, the cooling capacity of the micro-TEC with connecting wire length of 0 μm, 25 μm, 50 μm, 100 μm and 200 μm are 0.0023943 W, 0.0021351 W, 0.0021292 W, 0.0021173 W and 0.0020937 W respectively. Thus, the reduction of the cooling capacity caused by connecting wire is less than that of the COP loss. Further, the maximum COPs of the micro-TEC under the wire length ratio of 4:1, 3:2, 1:1, 2:3 and 1:4 are 0.87924, 0.8953, 0.9035, 0.91186 and 0.92922, during which current is 50 mA and temperature difference is 20 K. The cooling capacity of the micro-TEC under the length ratio of 4:1, 3:2, 1:1, 2:3 and 1:4 are 0.0020319 W, 0.0020729 W, 0.0020937 W, 0.0021148 W and 0.0021577 W respectively, during which the current of 50 mA and temperature difference of 20 K are implemented.
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