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The purpose of this study is to evaluate the efficiency of a Brazilian steelmaking company’s reheating process of the hot rolling mill.

The research method is a quantitative modeling. The main research techniques are data envelopment analysis, TOBIT regression and simulation supported by artificial neural networks. The model’s input and output variables consist of the average billet weight, number of billets processed in a batch, gas consumption, thermal efficiency, backlog and production yield within a specific period. The analysis spans 20 months.

The key findings include an average current efficiency of 81%, identification of influential variables (average billet weight, billet count and gas consumption) and simulated analysis. Among the simulated scenarios, the most promising achieved an average efficiency of 95% through increased equipment availability and billet size.

Additional favorable simulated scenarios entail the utilization of higher pre-reheating temperatures for cold billets, representing a large amount of savings in gas consumption and a reduction in CO2 emissions.

This study’s primary innovation lies in providing steelmaking practitioners with a systematic approach to evaluating and enhancing the efficiency of reheating processes.

Brazilian federalism was important in the political game of combating the pandemic for three reasons. First, Brazil's public health system depends heavily on intergovernmental relations between Union, states, and municipalities because there is a policy portfolio based on federative cooperation. Second, the subnational governments' autonomy to act against COVID-19 was constantly questioned by the Federal Government – the conflict between the President and governors was a key piece in all health policy. Finally, states and local governments were primarily responsible for policies to fight against pandemic, but the absence and/or wrong measures taken by the Federal Government (such as the delay in purchasing vaccines) generated intergovernmental incoordination, increased territorial inequality, and reduced the effectiveness of subnational public policies, especially those linked to social isolation. In this context, Brazilian federalism played a dual role in the pandemic. On the one hand, the federative structure partially succeeded in averting an even worse scenario, mitigating the impact of mistaken presidential decisions. The role of subnational governments, especially of the states, was critical as a counterweight to federal decisions. On the other hand, the President actively acted against governors and mayors and, above all, sought to weaken intergovernmental articulations within the Unified Health System (SUS), the federative model designed three decades ago. One could say that the federative actors, such as the Supreme Court (Supremo Tribunal Federal – STF) and subnational governments, were the main obstacles for the Bolsonarist antiscientific agenda. The success of this reaction to President Bolsonaro's negationist populism was partial, but the results of the fight against COVID-19 would have been much worse without these federalist barriers.

This paper aimed to develop a participatory methodology to analyze the disaster risk creation in coastal cities, based on an approach that combines social, urban, environmental and disaster risk elements.

The methodology uses some aspects of three theoretical approaches in a complementary way: i) the Pressure and Release (PAR) framework for the identification of dynamic pressures that contribute to disaster risk creation; ii) the application of Drivers, Pressure, State, Impact, Response (DPSIR) framework to analyze environmental dimensions; and iii) urban analysis, applying the Strengths, Weaknesses, Opportunities and Threats (SWOT) tool to classify urban processes. The methodology combined the use of satellite remote sensing data to analyze the urban sprawl and citizen science methods to collect social and environmental data, using the case study of the watershed of the Juqueriquerê River in the coastal city of Caraguatatuba, Brazil. The pilot project was part of a local university extension project of the undergraduate course on Architecture and Urban Planning and also engaged residents and city hall representatives.

The satellite remote sense data analysis indicated a continuous urban sprawl between 1985 and 2020, especially in the south of the Juqueriquerê watershed, reducing urban drainage and increasing the extension and water depth of urban flooding and riverine floods. Using citizen science methods, undergraduates identified settlements with limited economic resources to elevate houses and a lack of infrastructure to promote a resilient coastal city. After identifying the dynamic pressures that contribute to disaster risk creation and the weaknesses and strengths of a resilient city, undergraduate students proposed urban planning interventions and gray and green infrastructure projects to mitigate disaster risks.

The paper identifies urban sprawl in disaster-prone areas as one of the risk factors contributing to disaster. It also comprehensively analyzes differences between different zones in the Juqueriqere River, which will be useful for policy-making.

The method presented an interdisciplinary approach that used satellite remote sensing data and citizen science techniques to analyze disaster risks in coastal cities. The multidimensional approach used to evaluate risks is useful and can be replicated in other similar studies to gain a more comprehensive understanding of disaster risks.