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January 2022
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Temperature change analysis in Viçosa-MG through time series
Maurício Silva Lacerda, Alex da Silva Temoteo, Eduardo Campana Barbosa, Helgem de Souza Ribeiro Martins, Paulo César Emiliano
ABSTRACT: The theme of global warming came into evidence at the end of the 20th century and beginning of the 21st century and is a recurrent theme of research, debates and studies around the world. Thus, the main objective of this work is to analyze the behavior of monthly averages of maximum and minimum temperatures in Viçosa-MG, with the interest of verifying if this region, with interior characteristics and with a good part of preserved biodiversity, also suffers from warming temperatures like the larger cities. Furthermore, it is desired to make a temperature forecast for the following year with the secondary objective of testing the quality of the model for this purpose. For that, the Box and Jenkins methodology was used to model the historical series through the SARIMA models, and for the variance, a model of the GARCH class was adjusted, which was shown to be necessary for the minimum temperature series, as it presents heterogeneous variance. It was found that Viçosa's region has been suffering impacts similar to the rest of the world, with one °C warming in the maximum temperature historical series and an increase above 1.5 °C in the minimum temperature in the last 50 years of data records, there is an even more accentuated increase in the last 20 years of the series. Therefore, this study can contribute a lot, as it shows that smaller cities, although it does not have nearby industries, are also suffering from climatic variations and that better city and regional planning will be needed to deal with the consequences imposed by global warming.
[ FULL TEXT PDF 1-8 ] DOI: 10.22587/ajbas.2022.16.1.1
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Optimization and Controlling of Gas Hydrate Mitigation Methods in the Gas Wellhead Flowlines
Abdelaziz A. Noaman
ABSTRACT: Natural gas hydrate is a crystal composed of water molecules and light hydrocarbons. The high pressure and low temperature are satisfactory conditions for hydrate formation. However, the formation of hydrates causes clogs in gas-carrying pipelines, preventing transportation. Every day over two million US dollars are spent in the petroleum industry to prevent the formation of hydrates. The purpose of this paper is to investigate the hydrate formation phenomena at the eight gas wells of the gas project at different gas compositions in winter, different operating temperatures and pressures, and examine all available hydrate inhibition methods to select the most known method to solve the hydrate problems in the gas wells during the winter period mitigate. The available hydrate inhibition are methanol injection, monoethylene glycol (MEG) injection by piggyback with regeneration at CPF, low dosage of hydrate inhibitors (LHID), wellhead heating before pressure reduction e.g. B. using a gas-fired water bath heater. The PIPESIM steady-state simulator was used to calculate the hydration temperature for the eight wells in lean and rich winter gas compositions at different operating pressures and temperatures. Based on the hydration formation curves for the eight gas wells at rich and lean compositions, it can be stated that hydration inhibition is required at each flow line of the gas well head, especially in winter. Technical and economic comparisons were made between these available methods, based on suitability in North African countries, to select the most applicable method required for gas projects to mitigate the hydration problems in the gas wellhead flowlines. It has been determined that the methanol injection process is the best available process to use. Wellhead heating is considered a viable alternative to the methanol injection method, the required heat output for heating is 200 kW. Ambient temperature and water cut sensitivities were run on the eight gas wellhead flowlines at lean and rich gas compositions by the PIPESIM software. It has been found that the methanol dosing rate increases with decreasing ambient air temperature and increasing water fraction. The OLGA transient simulator was used to calculate the methanol dosing rate for each gas source at different ambient and soil temperatures. A comparison was made between the results of the two simulators and it was found that the methanal dosing rates in the OLGA results are 48% higher than the methanal dosing rates in the PIPESIM results.
[ FULL TEXT PDF 9-25 ] DOI: 10.22587/ajbas.2022.16.1.2
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The Role of Student Satisfaction on Student Commitment during the digital transformation era in Egypt: Higher education Sector
Nouran Nashaat1, Rasha Abd El Aziz, Marwa Tarek Abd El Azeem
ABSTRACT: In this article, we will examine whether students are satisfied with and committed to their e-learning experiences using a proposed model. It discusses a variety of variables and their effects on student satisfaction and academic commitment. Second, it examines the relationship between student satisfaction and commitment and each of the three variables examined, namely the course structure, the flexibility of online tutorials, and the quality of technology. The purpose of this research is to determine whether students are satisfied with and committed to their online learning experiences. Seven faculty members from an Egyptian higher education institution participated in a semi-structured interview with the researcher. This study analyses qualitative data collected online and via phone calls through interviews. The research is primarily concerned with students' commitment as behavior in e-learning, as well as their satisfaction with specific variables. The study focuses on a single institution of higher learning that utilizes e-learning technologies. The data analysis was conducted qualitatively rather than quantitatively, which may result in different interpretations of the results, which is considered a contribution. Other Egyptian higher education institutions' key variables require further investigation, with the possibility of expanding the investigation to other countries. Participants in this study will be individuals who are interested in student behavior in the digital age of e-learning and will find this research valuable
[ FULL TEXT PDF 26-34 ] DOI: 10.22587/ajbas.2022.16.1.3
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Attention-deficit/hyperactivity disorder
Leonardo Rezende Silveira, Ana Luisa Carreira da Silveira, Ariane Abreu Tsutsumi, Gabriela de Menezes Gagliotti, Carolina Santi Martinuzzo, Jhonas Geraldo Peixoto Flauzino, Lis Zilli Bertolini, Luiza Celeste Gebrin, Mariana Versiani Barreto, Maria Rita Souza Tomaz, Paulo Henrique Fugi, Rafaella Lobo Benedetti, Sebastião Carlos Filho
ABSTRACT: Studies indicate that Attention Deficit Hyperactivity Disorder (ADHD) appears to result from a combination of genetic, biological, environmental and social factors. In addition, neural tissue changes responsible for regulating executive functions also seem to be part of the etiology. ADHD is a neurodevelopmental disorder defined by inattention, disorganization and/or hyperactivity-impulsivity with genetic participation. Inattention, disorganization and inability to remain on a task, appearance of not hearing and loss of objects at levels inconsistent with age or level of development and is quite characteristic of carriers. ADHD usually persists in adulthood, resulting in social, academic and professional functioning impairments. From the literature review, it is observed that the methods used for the diagnosis of ADHD are efficient. According to their parents and teachers, children older than 6 years diagnosed using the fifth edition of the Diagnostic and Statistical Manual on Mental Diseases (DSM-5) or International Classification of Diseases (ICD-10) showed a significant difference in symptoms. Studies show that there has been a boom in ADHD diagnostic numbers in recent years, probably due to non-adhering to the DSM and ICD-10 criteria. Therefore, The DSM-5 and the ICD-10 should be used to allow an accurate diagnosis. Another point to be considered is that professionals who deal with this situation daily need to be trained to deal effectively with mental health, mainly related to the diagnosis of ADHD.
[ FULL TEXT PDF 35-41 ] DOI: 10.22587/ajbas.2022.16.1.4
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