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Vieira B.,Aeronautics Institute of Technology ITA | Junior W.S.,ita
Ambiente e Sociedade | Year: 2015

Advances in water management require knowledge of the availability and demand of water resources to define priority actions for water conservation. The aim of this study is to support the development of municipal initiatives involving Water Footprint, based on a case study of Caraguatatuba, using 2012 data. The following water footprints were considered: a) the urban water system; b) sewage production; c) cattle-farming; and d) rural water uses. Results showed water footprint levels of approximately 400 Mm3/year, where grey water represents the largest share (85%). Furthermore, results showed that the increased pressure on local water resources results from the disparity between the sewage system in relation to the demands of a growing population. This study can contribute to improve Water Footprint methodology, promoting comparative studies and supporting water management policies in this socio-political field. Source


Silveira F.F.,Federal University of Sao Paulo | Da Cunha A.M.,Aeronautics Institute of Technology ITA | Lisboa M.L.,Federal University of Rio Grande do Sul
Lecture Notes in Computer Science (including subseries Lecture Notes in Artificial Intelligence and Lecture Notes in Bioinformatics) | Year: 2014

Aspect-Oriented Software Development is a contemporary technique of software development that aims to improve the separation of concerns issues faced by traditional approaches. It improves the modularity of crosscutting concerns into units called aspects. However, this feature raises concerns about the quality of aspect-oriented programs (AOP). Existing functional testing approaches do not directly investigate the aspect composition problem, its resultant interactions and representation on a dynamic model. This paper describes a state-based testing method for AOP that targets class-aspect and aspect-aspect faults. To support the developed method, we introduce a model to represent the dynamic behavior of aspects interactions, a strategy to derive testing sequences, and a testing tool. Results of our assessment show that the approach is capable of detecting faults based on fault-models available in the literature. Furthermore, it is able to reveal another source of faults on AOPs, the aspect composition fault. © 2014 Springer International Publishing. Source


Panasiewicz J.,National Institute for Space Research | Pacheco G.M.,Aeronautics Institute of Technology ITA
SBMO/IEEE MTT-S International Microwave and Optoelectronics Conference Proceedings | Year: 2015

This article presents a photonic circuit that achieves direct carrier BPSK modulation of a RF signal from an opto-electronic oscillator suitable for satellite telemetry and control. The circuit was implemented with two Mach-Zehnder optical modulators. The optical wavelength is 1550 nm. One modulator was used to construct an optoelectronic oscillator to generate a carrier with frequency equal to 2.5 GHz. The second modulator was used to perform the BPSK direct modulation of the carrier signal. A bit rate of 1 Mbps was used and an EVM of 9.6% was obtained. The diagrams of the optoelectronic circuits and the modulation measurements are displayed. © 2015 IEEE. Source


de Medeiros-Junior R.A.,Aeronautics Institute of Technology ITA | de Lima M.G.,Aeronautics Institute of Technology ITA | de Medeiros M.H.F.,Polytechnic University of Mozambique
Environment, Development and Sustainability | Year: 2015

Chloride is one of the main factors responsible for damages related to the corrosion of the concrete reinforcement in marine environments. It is known that this mechanism of degradation is directly related to environmental variables. Within this context, it can be inserted the global climate change. This paper deals with the effects of temperature and relative humidity changes on the service life of concrete structures affected by chloride attack. This way, three situations of environmental aggressiveness were simulated: past, current, and future. Then, models for predicting the chlorides penetration were analyzed to the three selected situations. So, a practical methodology is presented, and the results are consistent with the literature data. Among the results, it can be noted that changes in temperature and relative humidity identified in a period of 100 years were responsible for a reduction from 7.8 to 10.2 years of service life. Most standards provide a design service life of 50 years for reinforced concrete structures. © 2014, Springer Science+Business Media Dordrecht. Source


De Moura Xavier J.C.,CETESB Sao Paulo State Environment Company | De Andrade Azevedo I.,Aeronautics Institute of Technology ITA | De Sousa Junior W.C.,Aeronautics Institute of Technology ITA | Nishikawa A.,CETESB Sao Paulo State Environment Company
Environmental Monitoring and Assessment | Year: 2013

Atmospheric pollutant monitoring constitutes a primordial activity in public policies concerning air quality. In São Paulo State, Brazil, the São Paulo State Environment Company (CETESB) maintains an automatic network which continuously monitors CO, SO2, NO x, O 3, and particulate matter concentrations in the air. The monitoring process accuracy is a fundamental condition for the actions to be taken by CETESB. As one of the support systems, a preventive maintenance program for the different analyzers used is part of the data quality strategy. Knowledge of the behavior of analyzer failure times could help optimize the program. To achieve this goal, the failure times of an ozone analyzer - considered a repairable system - were modeled by means of the nonhomogeneous Poisson process. The rate of occurrence of failures (ROCOF) was estimated for the intervals 0-70,800 h and 0-88,320 h, in which six and seven failures were observed, respectively. The results showed that the ROCOF estimate is influenced by the choice of the observation period, t 0 = 70,800 h and t 7 = 88,320 h in the cases analyzed. Identification of preventive maintenance actions, mainly when parts replacement occurs in the last interval of observation, is highlighted, justifying the alteration in the behavior of the inter-arrival times. The performance of a follow-up on each analyzer is recommended in order to record the impact of the performed preventive maintenance program on the enhancement of its useful life. © 2012 Springer Science+Business Media B.V. Source

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