Dissertaçõeshttps://repositorio.unifei.edu.br/jspui/handle/123456789/872024-03-27T13:00:31Z2024-03-27T13:00:31ZAquisição e validação de sinal de ruído eletroquímicohttps://repositorio.unifei.edu.br/jspui/handle/123456789/31732024-02-05T10:36:02Z2022-02-17T00:00:00ZAquisição e validação de sinal de ruído eletroquímico
Corrosion is a global problem, which implies costs in industrialized countries of up to
4.5% of GDP, with either economic, but also social and environmental impacts. In the
case of Brazil, the waste of water supply networks due to leaks loss is quite significant
and much of it is caused by network degradation, indicating that corrosion control
should be promoted whenever possible. This study proposes a corrosion monitoring
system, in system subject to the use of inhibitor, with the approach of passive
technique for monitoring corrosion by electrochemical noise (EN), in which the
classification of events in a corrosion sensor by EN is part of methodological study for
structural integrity (or “health”) monitoring system (SHM). Due to very dynamic and
stochastic nature of the signal, this study and analysis of EN measurements (ENM)
considers numerical and graphic characteristics of two corrosion systems both in saline
aqueous solution: carbon steel and stainless steel. These experiments are repeated for
accumulating data, which allow the generation of several graphs in time and frequency
domains, from which at least one characteristic is extracted, which has a good
correlation with data from corrosion processes. Then, based on a supervised machine
learning system, the training data allows the model to be calibrated. From the test
data, the correctness rate of the model above 50% is verified.
Dissertação
2022-02-17T00:00:00ZAcreditação e avaliação da qualidade de serviços odontológicoshttps://repositorio.unifei.edu.br/jspui/handle/123456789/40292024-03-26T13:13:05Z2024-02-06T00:00:00ZAcreditação e avaliação da qualidade de serviços odontológicos
The National Accreditation Organization developed an evaluation manual for health services, whose main criteria focused on Administrative Management, People Management and Care. Initially, in 1998, this program focused on evaluating hospitals. However, it was only in 2012 that the assessment criteria were adapted for dental services. With this in mind, the general aim of this study is to draw up an assessment of the quality of dental services, using the criteria established by the ONA's Brazilian Accreditation Manual and the Servqual model as a reference. To this end, the research method was defined as a case study in order to achieve validation in both public and private schools in a city located in the south of Minas Gerais. The results were evaluated using statistical tests and the Hierarchical Analysis Process. With the participation of 159 patients and seven dentists interviewed in the Municipal Network, the Servqual model shows that, for both interviewees, the quality sub-criteria were Equipment and Service provided correctly, on time; and the intervention sub-criterion was the fact that the Dentist was polite to the patient. In relation to the ONA model, patients pointed to the sub-criterion Channel as an improvement, the means of reporting abnormalities in relation to the service; for dentists, the improvement was the sub-criterion Hygiene of offices. In the parallel between seven dentists from the Municipal Network and five dentists from the Private Network, the criteria coincided. The results pointed to improvements, in relation to the Servqual model, in the Tangible, Safety in care and Professional responsibility criteria; and intervention strategies in the Empathy criterion. In relation to the ONA model, the criteria Organizational Leadership and Infrastructure Management had to be worked on with the other criteria used in the assessment to ensure all the gaps were filled and guarantee the effectiveness of the service. These results suggest that the criteria selected from the Servqual model and the ONA model were complementary in the evaluation of both networks. As a practical action, we propose the promotion of events to raise awareness of oral health, and thus reduce the indicators for seeking dental care.
Dissertação
2024-02-06T00:00:00ZUm estudo sobre a entropia topológica de sistemas dinâmicoshttps://repositorio.unifei.edu.br/jspui/handle/123456789/40282024-03-26T11:53:31Z2023-12-01T00:00:00ZUm estudo sobre a entropia topológica de sistemas dinâmicos
In this paper we will give a detailed proof of the Variational Principle which states that
the topological entropy of a continuous application defined in a compact metric space
is equal to the supremum of the entropies of invariant measures. We will also establish
topological, metric and conditional entropies in a more explicit way. All of was done with
reference to [11]. We will also show an example of the Variational Principle which shows
that the entropy of the set of non-errant points is the same as the entropy of the set of
non-errant points is the same as the entropy of space, that is, the entropy of a set is loaded
on the set of wandering points.
Dissertação
2023-12-01T00:00:00ZModelos análogos para a propagação da luz em teorias não lineares do eletromagnetismohttps://repositorio.unifei.edu.br/jspui/handle/123456789/40272024-03-25T12:10:45Z2024-03-08T00:00:00ZModelos análogos para a propagação da luz em teorias não lineares do eletromagnetismo
This work aims at studying analogous models for the propagation of light in nonlinear
theories of electromagnetism. To do this, we first calculate the equations of motion and the
momentum-energy tensor of an arbitrary theory dependent on the two electromagnetism
invariants, 𝐹 and 𝐺, in both tensorial and vector formalisms. Then, we demonstrate,
through two different methods, how to obtain the dispersion relation of electromagnetic
waves for these theories.We also calculate the phase velocity, group velocity and refractive
index for such theories. We apply the results to the Born-Infeld and Euler-Heisenberg
theories. Additionally, we find the phase velocity of a wave in a material medium exhibiting
Pockels and Kerr effects. We then propose a formal analogy between the effective metric
of the nonlinear theory and the effective metric of the material medium. Furthermore, we
show that we can obtain the same analogous result by relating the change in the value of
the refractive index due to the presence of electromagnetic fields in both nonlinear theories
with the change in the refractive index in the material medium due to the presence
of electromagnetic fields. Finally, we apply the obtained results in the construction of
analogous models based on Germanium and Silicon.
Dissertação
2024-03-08T00:00:00Z