7 resultados para Transient Presence

em Universidade Federal do Rio Grande do Norte(UFRN)


Relevância:

20.00% 20.00%

Publicador:

Resumo:

SOUZA,Roberto Mascarenhas et al.Presence of antibodies against Leishmania chagasi in haemodialysed patients.Transactions of the Royal Society of Tropical Medicine and Hygiene,v. 103, p.749-751, 2009.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

SOUZA, R. M. et al. Presence of antibodies against Leishmania chagasi in haemodialysed patients. Transactions of the Royal Society of Tropical Medicine and Hygiene, v. 103, n.7, p. 749—751. ISSN 0035-9203.

Relevância:

20.00% 20.00%

Publicador:

Resumo:

Originally aimed at operational objectives, the continuous measurement of well bottomhole pressure and temperature, recorded by permanent downhole gauges (PDG), finds vast applicability in reservoir management. It contributes for the monitoring of well performance and makes it possible to estimate reservoir parameters on the long term. However, notwithstanding its unquestionable value, data from PDG is characterized by a large noise content. Moreover, the presence of outliers within valid signal measurements seems to be a major problem as well. In this work, the initial treatment of PDG signals is addressed, based on curve smoothing, self-organizing maps and the discrete wavelet transform. Additionally, a system based on the coupling of fuzzy clustering with feed-forward neural networks is proposed for transient detection. The obtained results were considered quite satisfactory for offshore wells and matched real requisites for utilization

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This work consists in the use of techniques of signals processing and artificial neural networks to identify leaks in pipes with multiphase flow. In the traditional methods of leak detection exists a great difficulty to mount a profile, that is adjusted to the found in real conditions of the oil transport. These difficult conditions go since the unevenly soil that cause columns or vacuum throughout pipelines until the presence of multiphases like water, gas and oil; plus other components as sand, which use to produce discontinuous flow off and diverse variations. To attenuate these difficulties, the transform wavelet was used to map the signal pressure in different resolution plan allowing the extraction of descriptors that identify leaks patterns and with then to provide training for the neural network to learning of how to classify this pattern and report whenever this characterize leaks. During the tests were used transient and regime signals and pipelines with punctures with size variations from ½' to 1' of diameter to simulate leaks and between Upanema and Estreito B, of the UN-RNCE of the Petrobras, where it was possible to detect leaks. The results show that the proposed descriptors considered, based in statistical methods applied in domain transform, are sufficient to identify leaks patterns and make it possible to train the neural classifier to indicate the occurrence of pipeline leaks

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The processing of materials through plasma has been growing enough in the last times in several technological applications, more specifically in surfaces treatment. That growth is due, mainly, to the great applicability of plasmas as energy source, where it assumes behavior thermal, chemical and/or physical. On the other hand, the multiplicity of simultaneous physical effects (thermal, chemical and physical interactions) present in plasmas increases the complexity for understanding their interaction with solids. In that sense, as an initial step for the development of that subject, the present work treats of the computational simulation of the heating and cooling processes of steel and copper samples immersed in a plasma atmosphere, by considering two experimental geometric configurations: hollow and plane cathode. In order to reach such goal, three computational models were developed in Fortran 90 language: an one-dimensional transient model (1D, t), a two-dimensional transient model (2D, t) and a two-dimensional transient model (2D, t) which take into account the presence of a sample holder in the experimental assembly. The models were developed based on the finite volume method and, for the two-dimensional configurations, the effect of hollow cathode on the sample was considered as a lateral external heat source. The main results obtained with the three computational models, as temperature distribution and thermal gradients in the samples and in the holder, were compared with those developed by the Laboratory of Plasma, LabPlasma/UFRN, and with experiments available in the literature. The behavior showed indicates the validity of the developed codes and illustrate the need of the use of such computational tool in that process type, due to the great easiness of obtaining thermal information of interest

Relevância:

20.00% 20.00%

Publicador:

Resumo:

This thesis presents ⇡SOD-M (Policy-based Service Oriented Development Methodology), a methodology for modeling reliable service-based applications using policies. It proposes a model driven method with: (i) a set of meta-models for representing non-functional constraints associated to service-based applications, starting from an use case model until a service composition model; (ii) a platform providing guidelines for expressing the composition and the policies; (iii) model-to-model and model-to-text transformation rules for semi-automatizing the implementation of reliable service-based applications; and (iv) an environment that implements these meta-models and rules, and enables the application of ⇡SOD-M. This thesis also presents a classification and nomenclature for non-functional requirements for developing service-oriented applications. Our approach is intended to add value to the development of service-oriented applications that have quality requirements needs. This work uses concepts from the service-oriented development, non-functional requirements design and model-driven delevopment areas to propose a solution that minimizes the problem of reliable service modeling. Some examples are developed as proof of concepts

Relevância:

20.00% 20.00%

Publicador:

Resumo:

The study done has as objective the comprehension of the constructed territorial spaces through the commercial perspective, because it is a social practice which enables the dynamic of the space and the appearing of territories. Related to the territory, we emphasized the interest for the idea of used territory treated by Milton Santos, because we agreed with him believing that is the use of the territory which warrants its legitimacy. Then, the spatial dimension chose concentrates itself into the district of Alecrim, localized at the east zone of Natal/RN, where it is recognized by its strong commercial dynamic which was built during years, facing some events which happened in the context of the city. However, this dynamic counts with a hard dichotomy which involves as the considered by the State formal activities, as the informal one. About the commerce of the district, it has characteristics into its activities whose make him to be considered popular, as by the existing products, as by the strong presence of informal workers that constitutes the district s landscape. The informal workers practice expresses one of the multiples constructed alternative territorialities. We believe that this fact has direct relation with the growing process of the exclusion from the formal jobs market. Still talking about the spatial dimension, this real example of the Alecrim district shows how the techniques changes, together with the capitalism process, may influence one entire spatial dynamic across years, involving many agents, since the transient people from somewhere, until the State. Shall the Geography understand the multiple forms from the space, face to the relations that occur into it and also how new territories have been built