Navegando por Orientadores "SILVA, Marcelino Silva da"

Agora exibindo 1 - 7 de 7

Acesso aberto (Open Access)
Análise do QoE para streaming de vídeo em redes aéreas 5G mmWave de conectividade dupla
(Universidade Federal do Pará, 2022-02-18) PEREIRA, Ronilson Williame da Silva; SILVA, Marcelino Silva da; http://lattes.cnpq.br/7080513172499497
The evolution in mobile telecommunications has allowed the emergence of new network formats aimed at meeting the growing demand for wireless data, mainly fueled by more viewing of video content. The scarce spectrum available in current cellular networks does not seem to be able to meet this explosion of wireless data, motivating a shift to explore new frequency bands. Currently, one of the major problems of current mobile networks is congestion in denser areas such as concerts, sporting events, and festivals (temporary events), as we have a greater concentration of users, consequently increasing the volume of data traffic. Millimeter-wave (mmWave) communication, frequency bands between 30 and 300 GHz emerges as an essential part for the next generation of fifth-generation cellular networks (5G), as they adopt higher carrier frequencies offering high bandwidth and lower latency. However, system performance degrades due to high propagation loss and the sensitivity of the links to obstacles. To mitigate such factors, this dissertation proposes a dual connectivity 5G mmWave architecture using LTE (Long Term Evolution) and the use of UAVs (Unmanned Aerial Vehicles) as airbase stations to provide connectivity guarantees and quality of experience. in video streaming, one scenario where the proposal might be a suitable solution is to provide coverage for temporary events. Through simulations, an analysis of the Quality of Experience (QoE) was presented about the transmission of 4K videos in order to evaluate the transmission and quality of videos perceived by users. The simulated results show the efficiency of the system for multimedia applications using videos, improving the QoE of wireless users by 43%.
Acesso aberto (Open Access)
Análise dos fatores relacionados ao desempenho das escolas no IDEB: estudo de caso no Estado do Pará
(Universidade Federal do Pará, 2022-02-11) GOMES, Vitor Hugo Macedo; SILVA, Marcelino Silva da
The complexity of identifying all the factors that are related to the performance of schools on the Basic Education Development Index (IDEB) is enormous. In this study, three databases were analyzed with the objective of identifying several factors that correlate with low performance in state schools in the state of Pará. Initially, it was observed through the analysis that 142 municipalities in the state were at risk of not meeting the goal regarding the reduction of school dropouts and, consequently, affecting the performance of schools. This study used educational data mining techniques to, first, select variables with structural characteristics in the teaching environment, comparing the schools with higher and lower performance in IDEB, identifying possible relationships with school dropouts. Then, the Randon Florest (RF) algorithm was used to select the most important variables that directly or indirectly impact the IDEB index. After the selection phase, the variables were submitted to the Linear Regression (LR) algorithm. The results reveal that in the group of schools below average in IDEB, 60.6% reside in families with incomes up to one minimum wage, while 37.5% have incomes above one minimum wage. In the group of schools above average in IDEB, 42.4% live in families with incomes up to one minimum wage, while 51.6% live in families with incomes above one minimum wage. Evidencing that family income is related to better IDEB scores and, consequently, better infrastructure conditions. The results also indicate that the income of students’ families is related to the average family income in the analyzed municipalities. Next, variables related to parents’ income were used to identify a possible relationship between parents’ schooling and students’ performance. Finally, the analysis ends with the analysis of the impact of the Municipal Human Development Index (HDI) on the variables related to the students’ grades, the teachers’ qualifications, and the teachers’ experience in the school environment. The results reveal that there is a correlation between the index and student learning in the classroom. On the other hand, better IDEB scores are directly related to the adequacy of the curriculum to the subject taught, in addition to good working conditions for teachers.
Acesso aberto (Open Access)
Ciência de Dados Aplicada em Dados Públicos: Estudos de Caso Acerca da Previdência Social Brasileira.
(Universidade Federal do Pará, 2020-04-17) FELIX JÚNIOR, Francisco Eguinaldo de Albuquerque; SILVA, Marcelino Silva da; http://lattes.cnpq.br/7080513172499497
Data Science is an interdisciplinary area related to data analysis, which aims to extract knowledge and possible decision-making about specific problems. In this context, open government data, which often need pre-treatments and computational methods to process their data sets, present themselves as potential sources of information to be explored taking the Data Science’s perspective, allowing the development of strategies each time more efficient and optimized in public management. Given this, and allied to the recent discussions related to the reform in the Brazilian social security, this dissertation presents two case studies referring to analyzes in the national social security system. The first study used the microdata referring to the demographic censuses of 2000 and 2010, made available by IBGE, proposing to evaluate the participation that retirements and pensions have in the income inequality of the population in the years evaluated about Brazilian states and municipalities. The results show that, although the analyzed benefits contribute to the Brazil income concentration, the portion corres=ponding to a minimum wage contributes to the deconcentration of income, and the portion above one salary contributes to the concentration, being a repetitive pattern throughout the country. On the other hand, the second study proposed an evaluation of the impacts caused by the pension reform, which is proposed in PEC 06/2019. It was observed that PEC 06/2019 would hinder access to benefits, in which approximately 83,28% of the pensions would not have been granted had it been in effect since 1995.
Acesso aberto (Open Access)
Clustering-driven equipment deployment planner and analyzer for wireless non-mobile networks applied to smart grid scenarios
(Universidade Federal do Pará, 2018-03-16) VRBSKÝ, Ladislav; SILVA, Marcelino Silva da; http://lattes.cnpq.br/7080513172499497
The modern power grids, known as smart grids, rely on various advancements, one of them being the introduction of bi-directional communication. In some cases, data exchanged in the network is of critical importance. The data transmissions need to meet speci c delay limits set by the regulatory agencies in order for the smart grid to function properly. Meeting these standards allows the use of new applications of monitoring, control and system protection, resulting in a more e cient, stable and environment-friendly system. This thesis presents a methodology for analysis and planning of wireless communication networks for smart grid, which uses a clustering algorithm to determine the optimal positions of the routers and gateways of the network to be installed. After, it calculates the delay for each Intelligent Eletronic Device that is a network subscriber. This way, an analysis can be made to obtain the Quality of Service requested for a speci c network setup in a speci c scenario. The results obtained in the performed case study show that it is possible to achieve a network topology that satis es the maximum delay requirements of 100% of its subscribers, using WiMAX or a combination of Wi-Fi and WiMAX. Also, the thesis explores a restricted communication mode that can temporarily suspend the transferences of non-critical data. In most scenario con gurations, the restricted mode delivers all the data within the maximum delay. The software implementation of the proposed model is made publicly available under open-source license, so that anyone, including researchers, or private and public companies, can take advantage of it. The model presented in this thesis is customizable, allowing the use of other technologies and be used with other networks, including scenarios that are not related to smart grid.
Acesso aberto (Open Access)
Custo total de propriedade para infraestruturas de comunicações 5G para smart grid
(Universidade Federal do Pará, 2019-01-24) MELO, Paulo Tássio da Luz; SILVA, Marcelino Silva da; http://lattes.cnpq.br/7080513172499497
Smart Grid communications networks are considerably different from the traditional communica-tion systems used to access the Internet when considering users, applications, Quality of service and, especially, the impacts/losses due to malfunctions. Such data networks are generally owned and used exclusively by electrical system operators and require a high financial investment. There fore, this paper presents an economic analysis to compare different possibilities of data network deployment for the Smart Grid. The results showed that for the proposed scenario, 5G compared toother technologies, obtained the best evaluation for the implementation of the communication of a network of data applied to the Smart Grid, since the data of Quality of Service and the results obtained in the Total Cost of Property, showed that in the medium and long term the 5 Ghas its lower cost when faced with expenditures of other communication technologies, presenting 100% and 99.02% of IEDs with Quality of Service for uplink and downlink maximum, and the average IEDs served, is 100% for uplink and 99.4% for downlink in NORMAL and STRIP mode, respectively.
Acesso aberto (Open Access)
Data science aplicado a dados abertos do Governo Federal: estudos de caso sobre a economia dos municípios brasileiros.
(Universidade Federal do Pará, 2020-03-13) SANTOS, Sandio Maciel dos; SILVA, Marcelino Silva da; http://lattes.cnpq.br/7080513172499497
The process of analyzing open databases in recent years has gained considerable prominence in the Brazilian scenario since the granting of Law 12,527 / 2011, which guarantees access to public information, allowing for better transparency of public spending by society. Allied to this, numerous discussions arose around the use of Brazilian government microdata, among which we highlight the discussions on social security reform and the analysis of fiscal health in Brazilian municipalities through social security approaches. Thus, this work focuses on the use of Data Science, specifically in the KDD process to analyze microdata from Brazilian municipalities. Thus, in this work, two different approaches are made, the first of which performs a descriptive statistical analysis without inferences, to understand the fiscal health of Brazilian municipalities between 2010 and 2017, through transfers from the RGPS. The second approach to fiscal analysis using the STVAR model through the following variables: expenditure, revenue, and GDP of the municipality of São Paulo. The results of analysis I show that municipalities with populations greater than 100 inhabitants do not show a deficit due to the difference between municipal collections and transfers from the RGPS. In analysis II, the results found show that the economic cycle analyzed when undergoing exogenous shock (or external impulse) can generate changes in the states of recession and expansion with an average duration of 12 months.
Acesso aberto (Open Access)
Mineração de dados educacionais: um estudo sobre os dados socioeconômicos na educação na base de dados do INEP
(Universidade Federal do Pará, 2019-04-09) SANTOS, Aurea Milene Teixeira Barbosa dos; SILVA, Marcelino Silva da; http://lattes.cnpq.br/7080513172499497
This work investigates the profiles of the third year students of the Brazilian high school of the public and private school network, in order to identify which extracurricular and interscholastic factors influence the student to have a good performance in the National High School Examination (ENEM). In this way, two case studies were carried out, one with the socioeconomic records containing tens of thousands of samples from the students who took the exam, divided by each Brazilian region, making possible an analysis of the influential socioeconomic (extra-school) factors in each region. And the other study analyzed the attributes related to the conditions of school infrastructure offered by public (state) high schools in the state of Pará, for this study was related each note that the student obtained in the examination of enem with the base of the school census, that is, this database details the conditions of the secondary schools corresponding to each student who participated in the test of the enem both 2016. In order to reach the proposed objective, the two case studies were submitted to the process of Knowledge Discovery in Database, the educational data mining (EDM). In the MDE process, the main component analysis (PCA) technique was used in the preprocessing stage, in order to reduce the number of variables without losing the information provided by the total set, using this technique it was possible to decrease from 43 to 22 the number of variables analyzed in case study one, and 39 to 9 in the second case study, with a percentage of 0.8226% and 0.9099% respectively. This technique was used to propitiate the execution of another technique applied in the research, the Bayesian Networks, being used in the data mining stage, the choice for this technique was made possible by it to reason about uncertainties, especially in causes and effects having as presupposition the relationship of the variables and their probabilities of occurrences. Another inherent aspect is its structure, which concerns the comprehensibility of representation and results, which generate subsidies aimed at allowing specialists and users in the field to carry out more in-depth analysis on the subject treated by the data. The results showed the success of this methodology and the techniques used, the research allowed us to have a national analysis of the students of the third year of high school in Brazil, where no study performs this analysis at the Brazilian level when dealing with enem data. Strong influences of socioeconomic variables were pointed out highlighting as direct influential factors in student performance the difference if he studied in public, private or federal schools. Allied to this variable is the question of family income, if the student left or failed in elementary school, if he has access to the computer and internet in his residence and the shift in which he studied in high school, from these variables it was possible to perform inferences and analyze the probabilistic behavior of the grades obtained by the student with each one of these variables. When analyzing the influence of the school structure on the performance of the Paraense student of the public school, the variables library and science laboratory were highlighted. When analyzing only the state of Pará, it was verified that more than 80% of the students in the public network performed poorly, taking notes equal to or less than 450 in the enem, even though in their school the two variables were considered as influential.