In this paper, an improved mathematical model for flashover behavior of polluted insulators is proposed based on experimental tests. In order to determine the flashover model of polluted insulators, the relationship between conductivity and salinity of solution pollution layer of the insulator is measured. Then, the leakage of current amplitude of four common insulators versus axial, thermal conductivity and arc constants temperature was determined. The experimental tests show that top leakage distance (TLd) to bottom leakage distance (BLd) ratio of insulators has a significant effect on critical voltage and current. Therefore, critical voltage and current were modeled by TLd to BLd ratio Index (M). Also, salinity of solution pollution layer of the insulators has been applied to this model by resistance pollution parameter. On the other hand, arc constants of each insulator in new model have been identified based on experimental results. Finally, a mathematical model is intended for critical voltage against salinity of solution pollution layer of different insulators. This model depends on insulator profile. There is a good agreement between the experimental tests of pollution insulators obtained in the laboratory and values calculated from the mathematical models developed in the present study.
In the realm of modern education, the integration of technology has emerged as a powerful catalyst for transforming traditional classrooms into dynamic and engaging learning environments. This paper provides a concise overview of the multifaceted ways in which technology contributes to enhanced classroom engagement.
The most crucial factor in producing papaya seedlings successfully is seed germination. The purpose of this study was to investigate the influence of seed priming with growing media on seed germination and seedling growth of papaya from October to December 2022. The experimental treatments included three seed priming treatments: T0 = control (no seed priming treatments), T1 = GA3 (100 ppm), and T2 = KNO3 (1%), and four growing media, viz., M1 = soil + vermicompost (1:1), M2 = soil + cowdung (1:1), M3 = soil + cocopeat + vermicompost (1:1:1), and M4 = soil + cocopeat + cowdung (1:1:1). The treatments showed a significant effect on different parameters such as germination percentage, days to germination, survival percentage, chlorophyll content, seed vigor index, shoot, and root length. GA3 treated seedlings performed better than non-GA3-treated seedlings. Among the growing media, M3 showed the best for seed germination and other growth attributes compared to other growing media. In terms of interaction effects, T1M3 showed the highest performance for germination percentage (84.33%), survival percentage (91.0%), and chlorophyll content (44.26%). T1M3 also showed the highest seed vigor index, shoot and root growth, and plant biomass. As a result, the combination of GA3 and growing media containing soil + cocopeat + vermicompost was shown to be the most favorable for papaya seed germination and seedling growth.
The quality of preschool education is related to the stability of the early childhood teaching force. With the help of qualitative research methods, the study analyzed the data of eight teachers who left the profession and explored the process of teachers leaving the profession, and found that the encounter between "settling down" and "professional feelings", the struggle for transformation between "professional feelings" and "the situation", and the struggle for transformation between "settling down" and "the situation" are all related to the stability of the early childhood education workforce. It was found that the encounter and tug-of-war between "settling down" and "professional feelings", the struggle for transformation between "professional feelings" and "the situation", and the rational weighing between "settling down" and "the situation" are the important factors affecting the departure from the profession. The essence is the tension between "teachers as human beings" and "human beings as teachers". Therefore, it is necessary to pay attention to the unity of "person" and "teacher", and to alleviate the problem of teachers leaving the organization by creating a fair, democratic and professional working atmosphere and strengthening the awareness of professional education.
We analyze Thailand’s projected 2023–2030 energy needs for power generation using a constructed linear programming model and scenario analysis in an attempt to find a formulation for sustainable electricity management. The objective function is modeled to minimize management costs; model constraints include the electricity production capacity of each energy source, imports of electricity and energy sources, storage choices, and customer demand. Future electricity demands are projected based on the trend most closely related to historical data. CO2 emissions from electricity generation are also investigated. Results show that to keep up with future electricity demands and ensure the country’s energy security, energy from all sources, excluding the use of storage systems, will be necessary under all scenario constraints.
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