IFRN

São José dos Campos, Brazil
São José dos Campos, Brazil
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da Silva F.M.,Campus Universitario | de Andrade A.P.,INSA MCT | Fernandes P.D.,INSA MCT | Costa A.M.B.,IFRN
Revista Caatinga | Year: 2011

The objective of this research was to evaluate the behavior of thermal conductivity in the apparent surface in caatinga predominantly cactus, especially eunapolis [Pilosocereus gounellei (A. Weber ex K. Schum.)]. The study area was the river basin Taperoá, located in the region of Cariris Velhos in the State of Paraíba. Data were used for temperature and heat flux on the surface of vegetated soil. It used the law of heat conduction, who modeling time series of apparent thermal conductivity of the vegetation was made by Fourier methods, linear regression and polynomial. The results are partial, but antagonistic to literature, and they point out that the heat transfer by conduction in the caatinga has significance and should provide support for parameterization and incorporation of vegetation dynamics in the models are, hydrological, environmental or atmospheric circulation.


Teixeira C.S.L.,IFRN | de Medeiros P.G.,Federal University of Rio Grande do Norte | Ho L.L.,University of Sao Paulo
Producao | Year: 2014

This paper proposes an approach for monitoring the average number of non-conformities per items in short-run productions of N items. After every m produced items, the last r items are inspected. For each inspected item, the number of defects is counted; each inspected item is classified as approved if it meets the control limit criterion. If all r inspected items are approved, then the production goes on, otherwise it is stopped for adjustment. The inspected items are all discarded in case of production stoppage. After a production of N items, an additional lot is produced to complete the size ordered, but this additional lot does suffer inspection. A finite discrete state Markov chain is used to determine the transitory probabilities, which will be considered in terms of cost, to determine the optimal strategy for monitoring, obtained by optimizing three parameters: sampling interval (m), retrospective sample size (r), and control limit (cl). These parameters are obtained computationally by direct search to minimize the expression of the average cost per item produced. A numerical example illustrates the proposal.


de Oliveira E.N.A.,IFRN | Santos D.C.,Federal University of Campina Grande | Rocha A.P.T.,Federal University of Campina Grande | Gomes J.P.,Federal University of Campina Grande | da Silva W.P.,Federal University of Campina Grande
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2014

The objective was to study the physical and chemical stability of conventional umbu-caja (Spondias spp.) jams during storage for 180 days under ambient conditions. The jams were formulated through a factorial experimental design 22 with 2 experiments at the center point, resulting in 6 experiments, varying concentrations of sucrose (50, 55 and 60%) and pectin of high content of methoxylation (0.5; 1.0 and 1.5%). The formulations were heated and concentrated in open pan until it reached total soluble solids content of ≈65 °Brix, bottled in clear glass containers and stored at mean temperature and humidity of 23.25 °C and 81%, respectively, performing physical and chemical analysis at every 30 days storage. According to the results, the storage of jams promoted significant increase in pH, total soluble solids (° Brix), ratio (total soluble solids and total acidity), firmness and adhesiveness and significant reductions in data of water activity, total acidity, lightness (L*), intensity of yellow (+ b*), hue angle (h*) and chroma (c*). A tendency was found toward stabilization of values of moisture content and total solids in most experiments, whereas the intensity of red (+ a*) tended to increase in most jams.


Oliveira G.S.,IFRN | da Costa J.M.C.,Federal University of Ceará | Afonso M.R.A.,Federal University of Ceará
Revista Brasileira de Engenharia Agricola e Ambiental | Year: 2014

The hygroscopicity of the dehydrated food is related to its physical, chemical and microbiological stability. This study aimed to characterize the physico-chemical and hygroscopic behavior of freeze dried yellow mombin pulp powder with maltodextrin (DE20). Analysis of moisture, pH, soluble solids, titratable acidity, ascorbic acid, sugars, color, hygroscopicity and caking degree were performed. To obtain the isotherm, BET, GAB, Henderson and Oswin models were fitted and evaluated at 25 °C. The addition of maltodextrin to yellow mombin pulp resulted in a powder with a lower hygroscopicity and degree of caking. In addition, the results showed that the addition of maltodextrin provides a powder statistically different (p < 0.05) than the powder without maltodextrin with respect to moisture content, soluble solids, titratable acidity, ascorbic acid, sugars and color. The isotherms of the powders were classified as type III, characteristic of materials rich in carbohydrates. The results showed that the best fit of the isotherms were BET and Henderson models for the yellow mombin pulp powder and the yellow mombin pulp powder with maltodextrin, respectively. © 2014, Departamento de Engenharia Agricola - UFCG/Cnpq. All rights reserved.


Medeiros V.,Jr. | Medeiros V.,Federal University of Rio Grande do Norte | Deharbe D.,IFRN | Deharbe D.,Federal University of Rio Grande do Norte
Electronic Proceedings in Theoretical Computer Science, EPTCS | Year: 2014

This paper presents BEval, an extension of Atelier B to improve automation in the verification activities in the B method or Event-B. It combines a tool for managing and verifying software projects (Atelier B) and a model checker/animator (ProB) so that the verification conditions generated in the former are evaluated with the latter. In our experiments, the two main verification strategies (manual and automatic) showed significant improvement as ProB's evaluator proves complementary to Atelier B built-in provers. We conducted experiments with the B model of a micro-controller instruction set; several verification conditions, that we were not able to discharge automatically or manually with Atelier B's provers, were automatically verified using BEval. © V. Medeiros Jr. & D. De'harbe.


Danjour M.F.,IFRN | Do Nascimento Pereira D'anjour H.,Federal University of Rio Grande do Norte | De Oliveira P.W.S.,Federal University of Rio Grande do Norte
WMSCI 2012 - The 16th World Multi-Conference on Systemics, Cybernetics and Informatics, Proceedings | Year: 2012

This study aims to evaluate the influence of the brand in consumers' purchasing decisions of sports shoes. The methodology was a descriptive study that through the survey with the population of Natal - Brazil was analyzed to what extent the brand influence the buying decisions of the subjects studied. The results of the research identifying the most common and visible foundations of a value proposition of a brand are its benefits, which are directly related to the functions performed by the product to the client, so the most common and visible foundations of a proposal the value of a brand are its benefits, which are directly related to the functions performed by the product to the client, in addition, there is still a significant relationship of consumer emotion of sports shoes with sports brands, since these know how to work the trust and respect between the brand and the consumer. In conclusion, we identified the existence of influence of the brand in consumers' purchasing decisions of sports shoes in Natal / RN.


De Paiva F.A.P.,IFRN | Costa J.A.F.,Federal University of Rio Grande do Norte
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2012

Everyday a huge amount of pages are published on the Web, and, as a consequence, the users' difficulty to locate those that will meet their needs is increasingly bigger. The challenge for web designers and e-commerce companies is to identify groups of users that present similar interests in order to personalize navigation environments to meet those interests. In an attempt to offer that to the countless web users, in the last years, several researches have been done on clustering applied to Web Usage Mining. In this paper, a log file is preprocessed to map the sequence of visits for each user's session. A Session-Path Matrix is used as input to SOM Map and identifying patterns between each session. The results show the similarities between the sessions based on time spent on visited paths and volume transferred. © 2012 Springer-Verlag.


The purpose of this stydy was to assess the Cleaner Production - CP as a corporate sustainability tool, through a multiple case study in companies from the State of Rio Grande do Norte. To this end, our research methodology approach used the CP methodology from SEBRAE (2005) and applied it to the food industry (Company 1), the textile industry (Company 2) and to a car dealer (Company 3). Results highlighted, among other variables, the specific sustainability focus of any observed cleaner production activity. In company 1, raw material substitution, optimization of water and energy usage were the main foci. In Company 2, the foci were the optimization of fabric usage and technological modification (installation of washing equipment for the printing plates; before that, there was not control of water usage in this process, resulting in increased water consumption and disposal of waste). Company 3 was focused on source segregation and external recycling. However, these results pointed out that environmental, social and economic improvements demand corporate sustainability; and more commitment from executive management is needed to consider CP as an effective sustainable tool.


De Paiva F.A.P.,IFRN | Costa J.A.F.,Federal University of Rio Grande do Norte | Silva C.R.M.,Federal University of Rio Grande do Norte
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2014

Internet has become an increasingly constant presence everywhere that people go. Particularly this reality is visible in social networks and selling portals scenarios. Whatever scenario, there is plenty of space to improve accuracy since big data is a problem when scale increases. Semantic search is an alternative to improve search accuracy by understanding the contextual meaning of terms as they appear in the searchable data space. Among the several approaches to Semantic Search methodologies, a variation of Ontology-based search (or Logic Approach) is the one adopted. In this methodology, the engine not only understands hierarchical relationships of entities, however also more complex inter-entities relationships defined inside ontologies. This paper proposes a hybrid approach for the problem using Ontology-based Recommender Systems and semantic profiles. A portal prototype is designed and implemented for the domain of online dealership's vehicle buyer's market. Precision and Recall measures are the two major indices of information retrieval. They have been used to evaluate the prototype results. After calculating these two metrics over some searches, we have seen that Precision is 86.66% and Recall is 68.42%. These final results have demonstrated an improvement in the searches, particularly with regard the precision of the results provided to the users. © 2014 Springer International Publishing.


Da Costa J.A.,PM RN | Araujo N.,PM RN | Danjour M.F.,IFRN
WMSCI 2012 - The 16th World Multi-Conference on Systemics, Cybernetics and Informatics, Proceedings | Year: 2012

This study seeks to identify the organizational culture at the Centre for Development and Improvement of the Military Police of Rio Grande do Norte-Brazil (CFAPM) based on the model of organizational functioning styles of Paz and Mendes. Therefore, this study is considered to be descriptive and is classified as a case study and is predominantly quantitative in nature. It was conducted on 59 police officers working in CFAPM. The study allowed for the identification of the relationship between organizational culture and the socio-demographic subjects studied. The data was processed using statistical techniques applying the Chi-square, Fisher exact Test and Correspondence Analysis. The results indicated the predominance of the affiliative cultural style and from the police investigated a significant relationship between socio-demographic and cultural styles was seen and identified. Its predominance was evident in 55.9% of the police. This predominance was seen in all the general characteristics, showing organisational culture is influenced by these general characteristics. Finally, it is concluded that this study identifies that the cultural style that is predominant in CFAPM, is the affiliative, which has characteristics of standard collectivism, with a developed subculture style.

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