The influence of partial discharge exposure time on the thermally estimated depolarization and on the natural relaxation in polymer dielectrics is described. The polypropylene and polyethylene terephtalate foils were the object of investigations. Study of partial discharge plays an important role in the aging and the rupturing process of solid and mixed insulation systems. The PD analysis is a predictive test which indicates insulation degradation in advance, which may lead to the failure of the system, and it is performed under normal operating conditions.
English language is incorporated as a core module into the Saudi national curriculum. Students study and learn English 7 years and, during this period of time, they are assigned 13 English textbooks. However, they leave school knowing about 1000 words. This paper sheds light on factors that contribute to little vocabulary uptake by Saudi students when they leave high school. These factors are is that the vocabulary teaching methodology which is ” non-incremental ” and students are not repeatedly exposed to learnt vocabulary. Consequently, students do not fully master the English vocabulary which simply results in students not being able to retain the vocabulary in their minds. Recommendations that are promoted in this study include consulting the corpora to ensure that textbooks are provided with 5000 most frequent words, incorporating suitable graded readers into the curriculum, employing an effective methodology for vocabulary teaching and, most importantly, sufficient exposure to the target vocabulary items.