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Oliveira G.D.,Federal University of Santa Catarina | Bourscheidt D.M.,Federal University of Fronteira Sul
Journal of Environmental Management | Year: 2017

This paper uses the World Input-Output Database (WIOD) to test the hypothesis of per capita convergence in greenhouse gas (GHG) emissions for a multi-sectorial panel of countries. The empirical strategy applies conventional estimators of random and fixed effects and Arellano and Bond's (1991) GMM to the main pollutants related to the greenhouse effect. For reasonable empirical specifications, the model revealed robust evidence of per capita convergence in CH4 emissions in the agriculture, food, and services sectors. The evidence of convergence in CO2 emissions was moderate in the following sectors: agriculture, food, non-durable goods manufacturing, and services. In all cases, the time for convergence was less than 15 years. Regarding emissions by energy use, the largest source of global warming, there was only moderate evidence in the extractive industry sector—all other pollutants presented little or no evidence. © 2017 Elsevier Ltd


Dal Bosco Ducatti R.,Federal University of Fronteira Sul | Dal Bosco Ducatti R.,Cornell University | Ugine T.A.,Cornell University | Losey J.,Cornell University
Environmental Entomology | Year: 2017

The decline of the North American native lady beetle, Coccinella novemnotata Herbst, is strongly correlated with the introduction of Coccinella septempunctata L., and C. novemnotata are locally extirpated across much of the United States. Since C. novemnotata's decline, the invasive Harmonia axyridis Pallas has become dominant in North America. This study investigated whether H. axyridis has the potential to impede the recovery of C. novemnotata populations. To determine how H. axyridis interacts with C. novemnotata via intraguild predation and competition for prey, we paired first-instar C. novemnotata with first-instar H. axyridis at low and high densities of pea aphid. Coccinella novemnotata survival when paired interspecifically was significantly lower than H. axyridis survival at both aphid densities. Both species had similar weights at eclosion across aphid densities; however, H. axyridis developed faster than C. novemnotata. To examine the effect of larval size on intraguild interactions, we conducted a second experiment where we varied the C. novemnotata and H. axyridis instar in our pairings. Coccinella novemnotata survival and final weight increased when paired with younger H. axyridis larvae. The percentage survival of C. novemnotata in interspecific treatments, at the low aphid density, was lower than for sameaged C. novemnotata reared conspecifically, except for pairs initiated with C. novemnotata larvae that were two instars more advanced than H. axyridis larvae. These results suggest that intraguild predation and competition for prey by H. axyridis have the potential to affect the recovery of C. novemnotata populations negatively. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America.


Nunez-Gomez D.,Federal University of Santa Catarina | Alves A.A.D.A.,Federal University of Santa Catarina | Alves A.A.D.A.,Federal University of Fronteira Sul | Lapolli F.R.,Federal University of Santa Catarina | Lobo-Recio M.A.,Federal University of Santa Catarina
Chemosphere | Year: 2017

Mine-impacted water (MIW) is one of the most serious mining problems and has a high negative impact on water resources and aquatic life. The main characteristics of MIW are a low pH (between 2 and 4) and high concentrations of SO4 2− and metal ions (Cd, Cu, Ni, Pb, Zn, Fe, Al, Cr, Mn, Mg, etc.), many of which are toxic to ecosystems and human life. Shrimp shell was selected as a MIW treatment agent because it is a low-cost metal-sorbent biopolymer with a high chitin content and contains calcium carbonate, an acid-neutralizing agent. To determine the best metal-removal conditions, a statistical study using statistical planning was carried out. Thus, the objective of this work was to identify the degree of influence and dependence of the shrimp-shell content for the removal of Fe, Al, Mn, Co, and Ni from MIW. In this study, a central composite rotational experimental design (CCRD) with a quadruplicate at the midpoint (22) was used to evaluate the joint influence of two formulation variables—agitation and the shrimp-shell content. The statistical results showed the significant influence (p < 0.05) of the agitation variable for Fe and Ni removal (linear and quadratic form, respectively) and of the shrimp-shell content variable for Mn (linear form), Al and Co (linear and quadratic form) removal. Analysis of variance (ANOVA) for Al, Co, and Ni removal showed that the model is valid at the 95% confidence interval and that no adjustment needed within the ranges evaluated of agitation (0–251.5 rpm) and shrimp-shell content (1.2–12.8 g L−1). The model required adjustments to the 90% and 75% confidence interval for Fe and Mn removal, respectively. In terms of efficiency in removing pollutants, it was possible to determine the best experimental values of the variables considered as 188 rpm and 9.36 g L−1 of shrimp-shells. © 2016 Elsevier Ltd


Grzybowski J.M.V.,Federal University of Fronteira Sul | Macau E.E.N.,National Institute for Space Research | Yoneyama T.,Aeronautics Institute of Technology
Physica D: Nonlinear Phenomena | Year: 2017

This paper presents a self-contained framework for the stability assessment of isochronal synchronization in networks of chaotic and limit-cycle oscillators. The results were based on the Lyapunov–Krasovskii theorem and they establish a sufficient condition for local synchronization stability of as a function of the system and network parameters. With this in mind, a network of mutually delay-coupled oscillators subject to direct self-coupling is considered and then the resulting error equations are block-diagonalized for the purpose of studying their stability. These error equations are evaluated by means of analytical stability results derived from the Lyapunov–Krasovskii theorem. The proposed approach is shown to be a feasible option for the investigation of local stability of isochronal synchronization for a variety of oscillators coupled through linear functions of the state variables under a given undirected graph structure. This ultimately permits the systematic identification of stability regions within the high-dimensionality of the network parameter space. Examples of applications of the results to a number of networks of delay-coupled chaotic and limit-cycle oscillators are provided, such as Lorenz, Rössler, Cubic Chua's circuit, Van der Pol oscillator and the Hindmarsh–Rose neuron. © 2017 Elsevier B.V.


The decline of the North American native lady beetle, Coccinella novemnotata Herbst, is strongly correlated with the introduction of Coccinella septempunctata L., and C. novemnotata are locally extirpated across much of the United States. Since C. novemnotatas decline, the invasive Harmonia axyridis Pallas has become dominant in North America. This study investigated whether H. axyridis has the potential to impede the recovery of C. novemnotata populations. To determine how H. axyridis interacts with C. novemnotata via intraguild predation and competition for prey, we paired first-instar C. novemnotata with first-instar H. axyridis at low and high densities of pea aphid. Coccinella novemnotata survival when paired interspecifically was significantly lower than H. axyridis survival at both aphid densities. Both species had similar weights at eclosion across aphid densities; however, H. axyridis developed faster than C. novemnotata To examine the effect of larval size on intraguild interactions, we conducted a second experiment where we varied the C. novemnotata and H. axyridis instar in our pairings. Coccinella novemnotata survival and final weight increased when paired with younger H. axyridis larvae. The percentage survival of C. novemnotata in interspecific treatments, at the low aphid density, was lower than for same-aged C. novemnotata reared conspecifically, except for pairs initiated with C. novemnotata larvae that were two instars more advanced than H. axyridis larvae. These results suggest that intraguild predation and competition for prey by H. axyridis have the potential to affect the recovery of C. novemnotata populations negatively.


Fossati M.,Federal University of Santa Catarina | Scalco V.A.,Federal University of Santa Catarina | Linczuk V.C.C.,Federal University of Fronteira Sul | Lamberts R.,Federal University of Santa Catarina
Renewable and Sustainable Energy Reviews | Year: 2016

One of the alternatives to reduce building energy consumption recognized and used internationally is establishing standards for the evaluation and classification of buildings in terms of energy performance. In developed countries, the introduction of energy efficiency codes for residential and non-residential buildings started around the time of the first oil crisis in the mid-70s. Ten years later, Brazil has started implemented measures aimed at the conservation and rational use of energy. Initiatives in this regard began with the implementation of the Brazilian Labeling Program, where consumers are provided with information on the energy efficiency of appliances. However, the first energy efficiency law stimulated the most notable improvement in energy efficiency in 2001 after national energy crisis. As a result, the Regulation for Energy Efficiency Labeling of Commercial, Service and Public Buildings (RTQ-C) was released in February 2009 and the Regulation for Energy Efficiency Labeling of Residential Buildings (RTQ-R) was released in November 2010. Nowadays, the labeling of residential, commercial and service buildings is voluntary and the labeling of federal public buildings is mandatory since 2014. This paper presents a review of the building energy efficiency codes and labeling schemes all over the world, an overview of the Brazilian regulations on energy efficiency and discusses the labeling scheme for residential buildings adopted in Brazil. The process of its implementation, strengths and weaknesses in the present labeling scheme and the similarities and differences in relation to international experiences are described. The results obtained to date indicate that a revision is required in order to achieve a more flexible and economically viable process that will enable the program to be established as compulsory. © 2016 Elsevier Ltd


Lima-Filho A.C.,Federal University of Paraiba | Gomes R.D.,Federal University of Campina Grande | Adissi M.O.,Federal University of Paraiba | Da Silva T.A.B.,Federal University of Paraiba | And 2 more authors.
IEEE/ASME Transactions on Mechatronics | Year: 2012

The system proposed in this paper aims at monitoring the torque and efficiency in induction motors in real time by employing wireless sensor networks (WSNs). An embedded system is employed for acquiring electrical signals from the motor in a noninvasive manner, and then performing local processing for torque and efficiency estimation. The values calculated by the embedded system are transmitted to a monitoring unit through an IEEE 802.15.4-based WSN. At the base unit, various motors can be monitored in real time. An experimental study was conducted for observing the relationship between the WSN performance and the spectral occupancy at the operating environment. This study demonstrated that the use of intelligent nodes, with local processing capability, is essential for this type of application. The embedded system was deployed on a workbench, and studies were conducted to analyze torque and system efficiency. © 2012 IEEE.


Sahu N.,Kyoto University | Behera S.K.,Japan Agency for Marine - Earth Science and Technology | Ratnam J.V.,Japan Agency for Marine - Earth Science and Technology | Da Silva R.V.,Federal University of Fronteira Sul | And 5 more authors.
Climate Dynamics | Year: 2014

Extremely-low discharge events of the Paranaíba River basin during the austral summer season (December-February, DJF), are found to be associated with the Pacific sea surface temperature anomalies resembling the recently identified El Niño Modoki phenomenon. Extreme discharge events are identified based on their persistent flow for 7 days and more after taking retention time into consideration. Ninety percent of the extremely low discharge events during peak streamflow seasons of DJF, are found to occur during the El Niño Modoki years. A diagnostics study of atmospheric anomalies has shown a clear connection between the modified Walker circulation, associated with the El Niño Modoki, and the precipitation anomalies over the Paranaíba River basin. The climate variations have direct relationship with the rainfall. Streamflow variations are considered as the surrogates to rainfalls. Thus, El Niño Modoki phase is important component to understand and predict the streamflow variations in the Paranaíba River basin. © 2013 Springer-Verlag Berlin Heidelberg.


Bieseki L.,Federal University of Rio Grande do Norte | Treichel H.,Federal University of Fronteira Sul | Araujo A.S.,Federal University of Rio Grande do Norte | Pergher S.B.C.,Federal University of Rio Grande do Norte
Applied Clay Science | Year: 2013

Montmorillonite clay was treated with hydrochloric acid and subsequently pillared with aluminum polyoxocations. The acid-treated samples were evaluated for the removal of structural elements (Al, Fe and Mg) and for conservation of the lamellar organization. The more severe the treatment, the greater the specific area obtained. Despite the loss of structural organization, all samples were pillared, with a displacement of peak (001) to 2θ lower angles. The pillaring of all acid-treated samples promoted an increase in the specific area of these materials. Pillared samples previously treated at 50°C with HCl concentrations of 2 and 4molL-1 underwent an increase in their specific areas of approximately 45%. Pillared samples treated with 4molL-1 of HCl at 80°C underwent the lowest percent increase in surface area, approximately 10%, compared to the untreated samples. All samples possessed greater uniformity in pore size. Acid treatment prior to pillaring promoted an increase in the number of acid sites of moderate strength compared to pillared natural clay. © 2013 Elsevier B.V.


Santin F.M.,Federal University of Fronteira Sul | da Silva R.V.,Federal University of Fronteira Sul | Grzybowski J.M.V.,Federal University of Fronteira Sul
Ecological Engineering | Year: 2016

The design of riparian buffer strips (RBS) with adequate width to consistently serve conservation purposes is discussed. From the diverse ecological functions RBS, we concentrate on the filtering of agrochemicals, more especifically nitrogen loads due to uphill agriculture activity. In view of the numerous parameters that influence the RBS filtering properties, we propose and discuss a methodology to support the design of RBSs as a function of desired filtering properties. Towards this end, we use experimental data from previous studies on mean nitrogen influent, removal efficiency, soil type, vegetation density and mean RBS width to systematically train, validate and test about 6000 artificial neural networks (ANNs) of diverse architectures. The data from the original dataset are resampled using bootstrapping in order to provide a hundred training sets aimed at reducing the influence of stochastic variations in the training data upon the network outputs. We then compose an artificial neural network ensemble (ANNE) with the ANNs with best performances. The ensemble is aimed at delivering an estimate of RBS width when presented with unseen input data from the watershed. The relatively low values of test errors indicate that the neural networks retained relevant elements from the functional dependence between the input and output data. Sensitivity analysis is performed and indicates the vegetation cover type is the single most relevant input variable for the resulting model. We illustrate the application of the proposed methodology by presenting the study of the RBS from the Ligeiro River watershed, an important catchment in southern Brazil. The results from the ANNE are compared to those obtained by multiple linear regression, from which we conclude that the ANNE give consistently better results. At large, the results suggest that the existing buffer vegetation width is insufficient for filtering purposes and that the buffer width proposed in the Brazilian environmental law, thus suggesting that the quality of water supply for this catchment might be at risk. © 2016 Elsevier B.V.

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