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The tessellation problem is interesting to study, especially when it is associated with mathematical concepts. In this study, a graph coloring technique will be applied to solve the problem of wallpaper tessellation decoration. The main objective of this study is to improve students' meta-literacy abilities when applying coloring techniques in completing tessellation wallpaper decorations in RBL-STEM learning. RBL is a learning model that stands for Research-Based Learning. This model is now becoming the focus of attention of learning practitioners, while the STEM approach is an approach that involves four studies in the field of science, namely science, technology, engineering, and mathematics. The method used in this study is a mixed method, a combination of quantitative and qualitative. Quantitative methods were used to analyze the significant differences in the students' meta-literacy learning achievement between the control and experimental classes. In contrast, the qualitative method was used to analyze the results of in-depth interviews, a triangulation process from the quantitative research results. The results of this study indicate that there is a significant difference in meta-literacy ability between the control class (the class that applies RBL-STEM but without using the learning materials developed by the researcher) and the experimental class (the class that applies RBL-STEM using the learning materials developed by the researcher). The independent sample t-test on the post-test learning outcomes of meta-literacy abilities on Sig (2 Tailed) showed a significant difference of 0.013

Electronic nicotine delivery systems (ENDS) are the most used tobacco products among middle and high schoolers in the United States (U.S.). Familial relations and access play a major role in uptake among adolescents; yet the role of social media in this phenomenon in the context of communities impacted by tobacco-related health disparities is understudied. In Spring 2019, data were collected from adolescents in 8th and 9th grades in a school located in a rural distressed county in Tennessee to assess social media’s role in ENDS uptake. Descriptive and multivariable statistical analyses were performed to delineate factors associated with ENDS use. Of a total of 399 respondents, 12.5 % reported current ENDS use and 22.1 % indicated having ever discussed ENDS on social media. Closed messaging platforms (Snapchat) and video platforms (Facebook/Instagram/You Tube) were the most reported form of social media used (8.31 % and 8.31 % respectively). Social media use was positively associated with both ever ENDS use (odds ratio [OR] = 2.9) and current ENDS use (OR = 3.98). Parental advice against ENDS use was positively associated with ever ENDS use. In conclusion, social media use was positively associated with both ever and current ENDS use, and Snapchat was the most popular platform among this population of students. The results indicate that youth social media engagement may lead to exposure that can influence ENDS uptake. Future studies are needed to further examine these associations among distressed communities.

In controlled laboratory conditions, 62 samples of domestic fuels collected from 56 grids of Delhi were burnt to quantify the emissions of 23 non-methane volatile organic compounds (NMVOCs), i.e., alkanes (11), alkenes (6), alkynes (1) and aromatic compounds (5). The domestic fuels used for residential activities were comprised of 20 unique types of fuel woods, 3 species of crop residue, dung cakes and coal. These fuels are primarily used for cooking and water/space heating during winters. The current study reports the total emission budget of NMVOCs from domestic burning over Delhi. Furthermore, this study also compares the differences in EFs of NMVOCs which are calculated for different burning cycles and sample collection methods. The EFs of NMVOCs calculated from the samples collected during the flaming stage using canisters were analysed for 23 NMVOCs and then compared with same species emitted from complete burning cycle. In addition to this, 10 consumption and emission hotspot grids were also identified in Delhi; based on the ground survey and laboratory simulated results. The total annual usage of domestic fuels for the year 2019 was found to be 0.415 Mt/yr (million tonnes) in Delhi. 12.01 Gg/yr of annual NMVOC emissions was calculated from domestic fuel burning in which the emissions from dung cake and fuel wood dominated with 6.6 Gg/yr and 5.4 Gg/yr, respectively. The EFs of NMVOCs calculated using canister and online collection method differ significantly from each other. The flaming stage presented enhanced emissions compared to the complete burning cycle by ~7 times which suggests that the method of data analysis and the period of sample collection play a pivotal role in the preparation of an emission inventory and estimating the budget.

Transient and steady-state multiphysics numerical simulations are performed to investigate the thermal and electrical performances of a thermoelectric generator (TEG) module placed between hot and cold blocks. Effects of heat radiation, leg length and Seebeck coefficient on the TEG thermal and electrical performances are identified. A new correlation for the Seebeck coefficient with temperature is proposed. Radiation effects on the thermal and electric performances are found to be negligible under both transient and steady-state conditions. The leg length of the TEG module shows a considerable influence on the electrical performance but little on the thermal performance under transient conditions. A nearly linear temperature profile on a leg of the TEG module is identified. The temperature profile of the substrate surfaces is non-uniform, especially in the contacted areas between the straps (tabs) and the substrates.

The natural convective heat transfer phenomenon in an isolated, walled CCPC with PV cell is studied experimentally at 1000 W/m2 irradiance and 28.5 °C ambient temperature as well as 0°, 10°, 20°, 30° and 40° incidences in indoor laboratory by using solar simulator. Then a series of numerical simulations are launched to estimate the CCPC natural heat transfer behaviour and optical performance based on steady heat transfer and laminar flow models with grey optical option. It is identified that the heat transfer and optical performances of CCPC are dependent on the incidence. Especially, the PV cell is subject to the highest temperature at an incidence less than 20°, and otherwise the top glass cover is with the highest temperature. The predicted temperatures, Nusselt numbers and heat loss ratios are consistent with the experimental observations basically, especially at the incidence less than 20° with (−10.1~+3) % error in temperature, (−35.6~+12.6) % in Nusselt number, and (−1.2~+20.5) % in CCPC wall heat loss ratio. The optical parameters predicted agree very well with the measurements. The heat loss from the CCPC walls accounts for nearly 60% of the total incoming solar irradiance and should be paid significant attention in the design of CCPC.