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The Response of Benthic Foraminiferal Assemblages to Copper Exposure: A Pilot Mesocosm Investigation  [PDF]
Frontalini Fabrizio, Coccioni Rodolfo
Journal of Environmental Protection (JEP) , 2012, DOI: 10.4236/jep.2012.34044
Abstract: Controlled experiments, including mesocosms and laboratory cultures, are used to identify a potential speci?c cause- effect relationship that has been previously inferred in field studies. In this study, a series of mesocosm experiments are carried out to assess the impact of different concentrations of copper on benthic foraminiferal assemblages over time. This pilot investigation documents that Cu contamination has a detrimental effect on foraminifera when compared to original and control samples. In particular, increased concentrations of Cu (normally higher than 120 μg/l) lead to a lowering of foraminiferal density and diversity and an increased occurrence of abnormalities. This study thus supports that the use of an experimental approach is suitable for investigating the response of benthic foraminifera to stress including pollution. Moreover, the application of mesocosms represents an innovative tool to be placed alongside field studies and culture experiments.
Study of the Effects of Atmospheric Pressure in the Time Series of Muon Detector Using the Method of Spectral Analysis  [PDF]
Nivaor Rodolfo Rigozo
International Journal of Geosciences (IJG) , 2014, DOI: 10.4236/ijg.2014.53025

This paper presented a study of the effects of atmospheric pressure in the time series of muon detector using the method of spectral analysis of iterative regression. In which it observed that the periods of 4.8, 5.7, 7.0, 8.7, 10.7, 14.1, 16.2, 21.0, 31.2 and 356.7 days present in the amplitude spectrum of atmospheric pressure are also present in the amplitude spectra of muons data. Also it observed that the standardization of muons data to eliminate the effects of atmospheric pressure is efficient for periods under 7 days.

Geospatial Analysis of Geotechnical Data Applied to Urban Infrastructure Planning  [PDF]
Rodolfo Moreda MENDES, Reinaldo LORANDI
Journal of Geographic Information System (JGIS) , 2010, DOI: 10.4236/jgis.2010.21006
Abstract: The urbanization process inside the State of São Paulo (Brazil) facilitated, in approximately five decades, the migration of thousands of peasants to the urban areas of great industrial centers inducing and requesting, at the same time and very often, an amplification of the systems of local urban infrastructure not appropriate for the natural potential of the physical territory. In this content, the city of São José do Rio Preto (State of São Paulo) with little more than 350.000 inhabitants, currently faces serious problems related to the urban planning originating from the unusual occupation and without previous study of suitability. Therefore, the present paper intends to guide and indicate the areas whose potential of urban development leads to an occupation suitable for the construction of shallow foundations in residential buildings of single floor, using an interpretative chart produced by the software GIS-SPRING-4.0 developed by Instituto Nacional de Pesquisas Espaciais/INPE (Brazil), and based in the methodology of geotechnical mapping developed by the department of geotechnical engineering of EESC/USP (Brazil). The chart for shallow foundation shows that a large portion of the studied area presents serious relationship problems with layers of highly collapsible soils.
Apple’s Lion vs Microsoft’s Windows 7: Comparing Built-In Protection against ICMP Flood Attacks  [PDF]
Rodolfo Baez Junior, Sanjeev Kumar
Journal of Information Security (JIS) , 2014, DOI: 10.4236/jis.2014.53012

With the increase in the number of computers connected to Internet, the number of Distributed Denial of Service (DDoS) attacks has also been increasing. A DDoS attack consumes the computing resources of a computer or a server, by degrading its computing performance or by preventing legitimate users from accessing its services. Recently, Operating Systems (OS) are increasingly deploying embedded DDoS prevention schemes to prevent computing exhaustion caused by such attacks. In this paper, we compare the effectiveness of two popular operating systems, namely the Apple’s Lion and Microsoft’s Windows 7, against DDoS attacks. We compare the computing performance of these operating systems under two ICMP based DDoS attacks. Since the role of the OS is to manage the computer or servers resources as efficiently as possible, in this paper we investigate which OS manages its computing resources more efficiently. In this paper, we evaluate and compare the built-in security of these two operating systems by using an iMac computer which is capable of running both Windows 7 and Lion. The DDoS attacks that are simulated for this paper are the ICMP Ping and Land Attack. For this experiment, we measure the exhaustion of the processors and the number of Echo Request and Echo Reply messages that were generated under varying attack loads for both the Ping and Land Attack. From our experiments, we found that both operating systems were able to survive the attacks however they reacted a bit differently under attack. The Operating System Lion was handling both the Ping and Land attack in the exactly the same way, whereas Windows 7 handled the two attacks a bit differently, resulting in different processor consumptions by two different operating systems.

Entropy of Mixing and the Glass Transition of Amorphous Mixtures
Rodolfo Pinal
Entropy , 2008, DOI: 10.3390/entropy-e10030207
Abstract: Different equations have been proposed for estimating the glass transition temperature of amorphous mixtures. All such expressions lack a term to account for the effect of the entropy of mixing on the glass transition. An entropy based analysis for the glass transition of amorphous mixtures is presented. The treatment yields an explicit mixing term in the expression for the glass transition temperature of a mixture. The obtained expression reduces to the Couchman-Karasz equation in the limiting case where the contribution of the entropy of mixing approaches zero. Equivalent expressions are obtained for the glass transition temperature of a mixture of two glass formers as for the effect of a plasticizing liquid diluent on the glass transition temperature of an amorphous material.
Receptividad ganadera: marco teórico y aplicaciones prácticas
Ecolog?-a austral , 2009,
Abstract: this article is conceived as a didactic aid to use in graduate and post-graduate courses of ecology and grassland science. it aims to illustrate the concept of carrying capacity when applied to animal production systems, and also the difficulties involved in its calculus. the concept of carrying capacity derives from the classical logistic model of population growth, and is defined as the maximum density a population can attain in one habitat. however, that model assumes that (1) the environment is invariable in time and space, (2) all the individuals of the depredators or parasites. taking into account that these three assumptions are not fulfilled in animal production systems, and that human intervention alters ecosystem carrying capacity, the concept of carrying capacity of animal production systems differs from that of the logistic model. the carrying capacity of animal production systems has been defined as "the maximum animal density that can be maintained in one area under a certain production level without deteriorate the resource". the most adequate conceptual framework to understand the factors determining the carrying capacity of animal production systems is the model of energy flux. it suggests that domestic herbivores may consume only a proportion of aboveground net primary production, known as harvest index, to make a sustainable use of rangeland ecosystems. there not exist, until now, an universally accepted methodology to estimate the carrying capacity of animal production systems because of: (1) the lack of reliable models to predict harvest index in sites differing in environmental conditions or vegetation structure, or in different years or seasons, (2) the vast array of factors determining carrying capacity, including those directly linked to forage availability (as precipitation, fertility, soil texture, etc.) as good as those environmental factors unlinked to forage availability (as water availability, climatic risks, predators, etc.) and those
Tree species diversity in a seasonally-dry forest: the case of the Pinkaití site, in the Kayapó Indigenous Area, Southeastern limits of the Amazon
Salm, Rodolfo;
Acta Amazonica , 2004, DOI: 10.1590/S0044-59672004000300009
Abstract: this study investigates patterns of forest structure and tree species diversity in an anthropogenic palm grove and undisturbed areas at the seasonally-dry pinkaití research station, in the kayapó indigenous area. this site, managed by the conservation international do brasil, is the most southeastern site floristically surveyed in the amazon until now. the secondary and a nearby undisturbed forest were sampled in a group of 52 floristic plots of 0.0625-ha (25x25-m) where all trees with dbh > 10 cm were measured and identified. the analyses were complemented with other two floristic plots of 1-ha (10x1000-m). the present study has shown that the pinkaití, like other seasonally-dry forests, have great heterogeneity in forest structure and composition, associated with biotic characteristics of the most important tree species, natural disturbance and history of land-use. the palm grove, moderately dominated by the arborescent palm attalea maripa (aubl.) mart., presented high tree species diversity and was floristically similar to undisturbed forests at the study site. it is discussed the importance of large arborescent palms for the seasonally-dry amazon forests regeneration.
Desigualdade e polariza??o entre empregados na agricultura brasileira: 1992-2007
Hoffmann, Rodolfo;
Economia e Sociedade , 2009, DOI: 10.1590/S0104-06182009000200008
Abstract: the paper discusses the concept of polarization of an income distribution and examines the earnings distribution of employees in brazilian agriculture in the period 1992-2007. considering the period 1995-2007, after the monetary stabilization, it is shown that the inequality of that distribution is stable and that its degree of polarization has a decreasing trend. next, the paper analyses the changes in the inequality between permanent and temporary employees and between those with or without the legal employee's document, pointing to the different role of the legal minimum wage in influencing the earnings distribution within these worker categories. finally, the paper shows that the share of regional differences in the inequality of the distribution of wages in brazilian agriculture has increased.
Desigualdade da renda e das despesas per capita no Brasil, em 2002-2003 e 2008-2009, e avalia??o do grau de progressividade ou regressividade de parcelas da renda familiar
Hoffmann, Rodolfo;
Economia e Sociedade , 2010, DOI: 10.1590/S0104-06182010000300010
Abstract: using data from the 2008-2009 brazilian family budgets survey, this paper analyzes the main characteristics of the per capita family income distribution in brazil and its regions, compared to results obtained from the 2002-2003 survey. the distribution of total spending per capita is also analyzed. finally, the way in which the components of family income contributed to the increase or decrease in the country's income distribution in 2008-2009 is examined. it is shown that pensions of public servants are a strongly regressive component of the per capita family income, and that transfers from federal social programs are progressive, especially the bolsa família program.
Como aposentadorias e pens?es afetam a educa??o e o trabalho de jovens do domicílio
Hoffmann, Rodolfo;
Economia e Sociedade , 2010, DOI: 10.1590/S0104-06182010000100008
Abstract: the central question of this paper is to determine whether the component of the household income constituted by pensions affects the probability of the youngsters (15 to 21 years old) in the household being neither students nor labor suppliers. combining the possibilities of attending or not attending school and participating or not in the labor market, there are 4 situations whose probabilities are analyzed using a multinomial logit model. using data from the 2006 brazilian national household sample survey, it is shown that the income of pensioners contributes substantially to increase the probability of the household's youngsters being in school and not participating in the labor market. there is no evidence that pension incomes in a household increase the probability of their youngsters being simultaneously outside school and outside the labor market.
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