The Effect of E-Learning Approach on Studentsa Achievement in Fraction Math Course Level 5 at Yemens Public Primary School

E-learning (EL) is widely used in school and other organizations all over the world, because of difficulties in math skills (Remembering , understanding , application). There have not been any major surveys in the Yemen Public Primary School (YPPS) in that regard. This is the driving question behind this research: What is the effectiveness and usefulness of using e-learning approach in teaching the fraction math course for students of level 5 in the republic of Yemen on (Remembering , understanding , application) skills ? In this study, an experimental group of (30) students studying a course using e-learning approach. The control group (30) students they studying a course traditional learning, experimental design approach were used. The students2019; achievement was examined between two groups. The research results proved that there is a significant increase in gain in achievement, The EL has achieved efficiency greater than traditional learning in (Remembering, understanding, application) skills

MULTI-SCALE NUMERICAL APPROACH TO THE POLYMER FILLING PROCESS IN THE WELD LINE REGION

In this paper, a multi-scale coupling mathematical model is suggested for simulating the polymer filling process in the weld line region on a micro scale. The model considers two aspects: one is the coupling model based on stresses in the whole cavity region; the other is the multi-scale coupling model of continuum mechanics (CM) and the molecular dynamics (MD) in a weldline region. A weak variational formulation is constructed for the finite element method (FEM), which is coupled with the Verlet algorithm based on the domain decomposition technique. Meanwhile, an overlap region is designed so that the FEM and the MD simulations are consistent with each other. The molecular backbone orientation of the whole cavity is illustrated and the position of the weld line is determined by the characteristics of the molecular backbone orientation. Finally, the properties of the polymer chain in the weld line region are studied conformationally and dynamically. The conformational changes and movement process elucidate that the polymer chains undertake stretching, entangling and orientating. Moreover, the effect of the number of chains and melt temperature on the spatial properties of chain conformation are investigated

Information transmission and hedging effectiveness for the pairs crude oil-gold and crude oil-Bitcoin during the COVID-19 outbreak

This study uses hourly data to analyse the return and volatility transmission of oil-gold and oil-Bitcoin pairs during the preCOVID-19 and COVID-19 periods. The results show that the return transmissions vary across the two periods for both pairs. There is a unidirectional volatility spill-over from gold to oil in the preCOVID-19 period, and from oil to gold during the COVID-19 period. There is a significant volatility spill-over from Bitcoin to oil during the pre-COVID-19 period, whereas no evidence of volatility spill-over between oil and Bitcoin is shown during the COVID-19 period. Based on optimal weights, investors should increase their investments in, (a) gold for a portfolio of oil-gold, and (b) Bitcoin for a portfolio of oil-Bitcoin during the COVID-19 period. All hedge ratios are higher during the COVID-19 period, implying a higher hedging cost compared to the pre-COVID-19 period. The results of hedging effectiveness reveal that the risk-adjusted returns can be improved by constructing a portfolio of oil-gold and oil-Bitcoin during both sample periods. Further results reveal that gold is a strong safe haven and a hedge for the oil market, while Bitcoin serves as a diversifier for the oil market during the COVID-19 period