Gabriel Pereira | Universidade do Estado da Bahia (original) (raw)

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Papers by Gabriel Pereira

How and why do democratic governments overcome amnesty laws and cultures of impunity to allow for... more How and why do democratic governments overcome amnesty laws and cultures of impunity to allow for trials for past human rights violations? To confront this question, we &#64257;rst identify widespread agreement on four key factors associated with the degree of accountability in a new democracy: civil society demand, domestic judicial leadership, the absence of veto players and international pressure. We then outline the interactions among those factors that lead to four distinct scenarios of overcoming amnesty, from the failure to do so (obstinate amnesties) to successful democratic displacement of amnes- ties and the proliferation of trials. Because Latin America has had great variation in these accountability pathways, we use it as a test region to examine the dynamic interaction of the four key factors in overcoming impunity. We conclude by considering this new dynamic interaction framework outside Latin America.

Comparative and International Perspectives, 2012

This chapter accounts for the political and judicial processes of accountability that led to the ... more This chapter accounts for the political and judicial processes of accountability that led to the overturning of Argentina's amnesties and the reopening of trials for human rights violations committed by the military regime that ruled the country from 1976 to 1983. 2 It locates these processes in the broader context of transitional justice in Argentina and examines the role of the main actors involved. The chapter also identifies the key factors that explain the Argentine pathway to accountability and evaluates the extent of Argentina's uniqueness as the first country in Latin America to overturn domestic legislation shielding perpetrators of grave human rights crimes from prosecution.

Remote Sensing, 2011

Land cover plays a major role in many biogeochemical models that represent processes and connecti... more Land cover plays a major role in many biogeochemical models that represent processes and connections with terrestrial systems; hence, it is a key component for public decisions in ecosystems management. The advance of remote sensing technology, combined with the emergence of new operational products, offers alternatives to improve the accuracy of environmental monitoring and analysis. This work uses the GLOBCOVER, the Vegetation Continuous Field (VCF), MODIS Fire Radiative Power (FRP) and the Tropical Rainfall Measuring Mission (TRMM) remotely sensed databases to analyze the biomass burning distribution, the land use and land cover characteristics and the percent of tree cover in South America during the years 2000 to 2005. Initially, GLOBCOVER was assessed based on VCF product, and subsequently used for quantitative analysis of the spatial distribution of the South America fires with the fire radiative power (FRP). The results show that GLOBCOVER has a tendency to overestimate forest classes and to underestimate urban and mangroves areas. The fire quantification based on GLOBCOVER product shows that the highest incidence of fires can be observed in the arc of deforestation, located in the Amazon forest border, with vegetation cover composed mainly of broadleaved evergreen or semi-deciduous forest. A time series analysis of FRP database indicates that biomass burning occurs mainly in areas of broadleaved evergreen or semi-deciduous forest and in Brazilian Cerrado associated with grassland management, agricultural land clearing and with the deforestation of Amazon tropical rainforest. Also, variations in FRP intensity and OPEN ACCESS Remote Sens. 2011, 3 2111 spread can be attributed to rainfall anomalies, such as in 2004, when South America had a positive anomaly rainfall.

Ambiente e Agua - An Interdisciplinary Journal of Applied Science, 2010

2012 IEEE International Geoscience and Remote Sensing Symposium, 2012

ABSTRACT Burned areas map is essential in many applications and the orbital sensors have been use... more ABSTRACT Burned areas map is essential in many applications and the orbital sensors have been used to monitor fires for many years, providing a better understanding of processes at different scales and being the only practical technique to estimate fires in large areas. However, remote sensing methods have limitations that could cause errors in the final products. Therefore, the objective of this work is to evaluate the MCD45A1 burned area product derived from MODIS sensor in Amazon tropical forest by comparing this dataset with the reference data derived from the mapping of burned areas in Acre State/Brazil acquired by TM sensor aboard of Landsat 5 and with a fieldwork that took place in November 2011. The results showed that de MCD45A1 product presented 93% of omission errors in 2010 and 96% in 2011 year in relation to reference data, presenting a low confidence in identifying the burned areas in Amazon region.

Ambiente e Agua - An Interdisciplinary Journal of Applied Science, 2012

Remote Sensing, 2014

The objective of this study was to analyze the spatial and temporal distribution of burned areas ... more The objective of this study was to analyze the spatial and temporal distribution of burned areas in Rondônia State, Brazil during the years 2000 to 2011 and evaluate the burned area maps. A Linear Spectral Mixture Model (LSMM) was applied to MODIS surface reflectance images to originate the burned areas maps, which were validated with TM/Landsat 5 and ETM+/Landsat 7 images and field data acquired in August 2013. The validation presented a correlation ranging from 67% to 96% with an average value of 86%. The lower correlation values are related to the distinct spatial resolutions of the MODIS and TM/ETM+ sensors because small burn scars are not detected in MODIS images and higher spatial correlations are related to the presence of large fires, which are better identified in MODIS, increasing the accuracy of the mapping methodology. In addition, the 12-year burned area maps of Rondônia indicate that fires, as a general pattern, occur in areas that have already been converted to some land use, such as vegetal extraction, large animal livestock areas or diversified permanent crops. Furthermore, during the analyzed period, land use conversion associated with climatic events significantly influenced the occurrence of fire in Rondônia and amplified its impacts. OPEN ACCESS Remote Sens. 2014, 6 8003

International Journal of Remote Sensing, 2012

Satellite imagery is formed by finite digital numbers representing a specific location of ground ... more Satellite imagery is formed by finite digital numbers representing a specific location of ground surface in which each matrix element is denominated as a picture element or pixel. The pixels represent the sensor measurements of spectral radiance. The radiance recorded in the satellite images is then an integrated sum of the radiances of all targets within the instantaneous field of view (IFOV) of the sensors. Therefore, the radiation detected is caused by a mixture of several different materials within the image pixels. For this reason, spectral unmixing has been used as a technique for analysing the mixture of components in remotely sensed images for almost 30 years. Different spectral unmixing approaches have been described in the literature. In recent years, many authors have proposed more complex models that permit obtaining a higher accuracy and use less computing time. Although the most widely used method consists of employing a single set of endmembers (typically three or four) on the whole image and using a constrained least squares method to perform the unmixing linearly, every different algorithm has its own merits and no single approach is optimal and applicable to all cases. Additionally, the number of applications using unmixing techniques is increasing. Spectral unmixing techniques are used mainly for providing information to monitor different natural resources (agricultural, forest, geological, etc.) and environmental problems (erosion, deforestation, plagues and disease, forest fires, etc.). This article is a comprehensive exploration of all of the major unmixing approaches and their applications.

Environmental Research Letters, 2013

There is an error in figure 7; figure 7(a) is the same as figure 6(a). The corrected figure and c... more There is an error in figure 7; figure 7(a) is the same as figure 6(a). The corrected figure and caption are given below.

Introdução O Código Civil Brasileiro de 2002 apresenta, no livro das obrigações, diversas espécie... more Introdução O Código Civil Brasileiro de 2002 apresenta, no livro das obrigações, diversas espécies de contratos. Dentre elas, em seu Capítulo VIII, nos artigos 610 ao 626 dispõe sobre o contrato de Empreitada. O contrato de empreitada é recorrente na atualidade e de diversas formas, portanto seu estudo é de grande importância devido à sua recorrente aplicação prática. 2. Conceito O conceito de "empreitada" no dicionário refere-se à "obra que se faz segundo determinadas condições por um preço previamente estipulado"[1], definição esta que se aproxima muito da modalidade de contrato em espécie prevista no Código Civil Brasileiro de 2002. Pelo contrato de empreitada, pode-se perceber também que "uma das partes, denominada empreiteiro, empresário ou locador, obriga-se a executar uma obra, mediante pagamento de um preço que outra parte, denominada dono da obra, comitente ou locatário, compromete-se a pagar."[2] Empreitada é um tipo de contrato previsto nos artigos 610 a 626 do Código Civil Brasileiro de 2002. Trata-se de obrigação de resultado, que não leva em conta a atividade do empreiteiro por si só, objetivando apenas o fruto final, podendo ser a concretização de uma obra material ou até mesmo intelectual. A remuneração estipulada previamente e é feita pela obra final, independente do tempo.[3] É de suma importância verificar a conceituação dos grandes juristas brasileiros acerca da empreitada, pois através do conceito percebe-se que "identificam-se claramente três elementos do contrato: os sujeitos, o preço e a realização da obra para entrega futura."[4]