Romildo Morant de Holanda

Shannon information entropy for assessing space-time variability of rainfall and streamflow in semiarid region.

The principle of maximum entropy can provide consistent basis to analyze water resources and geophysical processes in general. In this paper, we propose to assess the space-time variability of rainfall and streamflow in northeastern region of Brazil using the Shannon entropy. Mean values of marginal and relative entropies were computed for a 10-year period from 189 stations in the study area and entropy maps were then constructed for delineating annual and seasonal characteristics of rainfall and streamflow. The Mann-Kendall test was used to evaluate the long-term trend in marginal entropy as well as relative entropy for two sample stations. High degree of similarity was found between rainfall and streamflow, particularly during dry season. Both rainfall and streamflow variability can satisfactorily be obtained in terms of marginal entropy as a comprehensive measure of the regional uncertainty of these hydrological events. The Shannon entropy produced spatial patterns which led to a better understanding of rainfall and streamflow characteristics throughout the northeastern region of Brazil. The total relative entropy indicated that rainfall and streamflow carried the same information content at annual and rainy season time scales.

Entropy theory for analysing water resources in northeastern region of Brazil

ABSTRACT Using the Shannon entropy, the space–time variability of rainfall and streamflow was assessed for daily rainfall and streamflow data for a 10-year period from 189 stations in the northeastern region of Brazil. Mean values of marginal entropy were computed for all observation stations and entropy maps were then constructed for delineating annual and seasonal characteristics of rainfall and streamflow. The Mann-Kendall test was used to evaluate the long-term trend in marginal entropy as well as relative entropy for two sample stations. The marginal entropy values of rainfall and streamflow were higher for locations and periods with the highest amounts of rainfall. The entropy values were higher where rainfall was higher. This was because the probability distributions of rainfall and the resulting streamflow were more uniform and less skewed. The Shannon entropy produced spatial patterns which led to a better understanding of rainfall and streamflow characteristics throughout the northeastern region of Brazil. The total relative entropy indicated that rainfall and streamflow carried the same information content at annual and rainy season time scales.

Cerâmica Vermelha – Desperdício na Construção Versus Recurso Natural Não Renovável: Estudo de Caso nos Municípios de Paudalho/PE e Recife/PE (Red Ceramic - Construction Waste Versus Non-Renewable Natural Resource: A Case Study in Paudalho - PE and...)

A construcao civil e um setor muito importante da economia e para a sociedade, e dentre os seus principais sub-setores o de edificacoes e um grande consumidor de tijolos cerâmicos, pois e um dos principais insumos para fechamento de vaos em casas e apartamentos. O tijolo cerâmico e, em sua totalidade, constituido de argila, no caso um recurso natural nao renovavel finito. Apos a sua extracao nas jazidas e de sua sinterizacao o elemento cerâmico passa a existir e o recurso mineral nao metal que compoe a argila nao mais existe. Mesmo sendo importante a industria da Construcao Civil, sub-setor Edificacoes (ICC/SE) ainda mantem niveis altos de perdas de insumos, raramente quantificados. Neste sentido, o presente trabalho teve por objetivo a quantificacao das perdas da cerâmica vermelha na construcao civil no estado de Pernambuco. Foram levantados dados em duas edificacoes localizadas na cidade do Recife, por um periodo de seis meses no ano de 2010. Nas duas obras foram registradas perdas medias de 20,45% de alvenaria e isso acarretou um desperdicio tambem da materia prima argila, pois o residuo gerado nao mais constitui recurso natural e sim residuo solido com grande potencial de impactar o meio ambiente. Concluiu-se, ainda, que ha de serem adotadas medidas preventivas com urgencia vez que as perdas anuais de argila, somente no estado de Pernambuco, sao da ordem de 300.000 m 3 , o que representa um grande risco ambiental. Palavras-chave: Risco ambiental; tijolo cerâmico, desperdicios na construcao civil. Red Ceramic - Construction Waste Versus Non-Renewable Natural Resource : A Case Study in Paudalho - PE and Recife - Cities ABSTRACT The building sector is a very important section of the economy and for the society, and among their main sub-sections the one of constructions is a great consumer of ceramic bricks, because it is one of the main inputs for closing of spaces in houses and apartments. The ceramic brick is, in its totality, constituted of clay, in the case a natural resource no renewable. After its extraction in the beds and of its clay coalitionthe ceramic element starts to exist and the mineral resource no metal that composes the clay no more it exists. Even of great importance the building sector industry, sub-section Constructions (BSI/SC) it still maintains high levels of losses of inputs, rarely quantified. In this sense, the present work had for objective the quantification of the red ceramic losses in a building site in the State of Pernambuco. Data collected in two constructions located in Recife city for a period of six months in the year of 2010 were used for quantification of the losses. The two sites presented an average losses of 20,45% and that caused a waste of the primary matter clay, because the generated residue is no more a natural resource and it represents a solid residue with great potential the environment impact. It was concluded that some urgent attitudes must be adopted in order to reduce such waste since that the annual losses of clay, only in the State of Pernambuco, represent an approximate volume of 300,000 m 3 , what represents a great environmental risk. Key-Word: I scratch out environmental; ceramic brick, wastes in the building site.