Modelos para a Localização de Aterros Sanitários em São Tomé e Príncipe

O presente estudo denominado modelos para a localização de aterros sanitários em São Tomé e Príncipe utiliza a análise multicritério, método Analytical Hierarchy Process (AHP), em Sistemas de Informação Geográfica (SIG), para a localização de aterros sanitários na ilha de São Tomé, STP. A metodologia apresentada combina análise qualitativa, feita a partir de inquéritos aos especialistas, e análise quantitativa em ambiente SIG, quer para o diagnóstico da situação atual da Ilha, no respeitante à disposição das lixeiras existentes, quer para a determinação cientificamente fundamentada dos melhores locais para instalação de futuro aterro sanitário. O objetivo geral desta investigação foi, a partir de uma abordagem SIG e mixed-methods, criar um modelo que sirva de apoio à decisão e ao desenvolvimento sustentável de São Tomé e Príncipe. Relativamente aos objetivos específicos, esta investigação pretendeu: (i) desenvolver, através da experimentação, uma metodologia e um modelo que seja o mais ajustado possível à realidade; (ii) analisar a aptidão física e legal/jurídica para a localização de aterros sanitários na Ilha de São Tomé. Os dados recolhidos e posteriormente analisados foram classificados, como sendo de natureza social, demográfica, económica, biofísica, legislativa, política e ou de movimento de cidadãos. O modelo combinado SIG e Análise Multicritério demonstrou ser uma excelente ferramenta de apoio à decisão. Numa primeira fase, o modelo permitiu revelar, a partir do diagnóstico da situação atual da disposição das lixeiras, algumas incongruências espaciais, legais, ambientais e de saúde pública; numa segunda fase, o modelo veio - em respeito aos determinantes legais, sociais, económicos, ambientais e de saúde pública - determinar quais as unidades territoriais com aptidão (Baixa, Média e Alta). O modelo incorporou, para ajuste das ponderações aos critérios e ganho de robustez científica, opinião de especialistas nacionais e internacionais, recolhidas das respostas aos inquéritos. Em síntese, o modelo identificou áreas adequadas para a localização do aterro sanitário ou áreas ótimas para a deposição dos RSU em São Tomé, com o propósito de servir como apoio à tomada de decisão. A implementação do modelo permitiu obter mapas de aptidão, para a localização de um aterro sanitário na ilha de São Tomé. Os resultados decorreram da análise combinada de 14 (catorze) critérios, em respeito pelos limites jurídicos/legais, projeções demográficase potencial produção de lixo, valores ambientais e de saúde pública, e considerações de carácter económico. Os resultados de aptidão indicados pelo modelo foram classificados como Nula, Baixa, Média e Alta aptidão, de acordo com a análise ponderada dos critérios. Por fim, para um maior ajuste dos resultados, e para as áreas classificadas de Alta aptidão, efetuou-se uma seleção das áreas iguais ou superiores a 12 hectares para a implantação do aterro sanitário na Ilha de São Tomé.The present study is about building a model capable to identify the best location for sanitary landfills in São Tomé and Príncipe by combining multicriteria analysis, Analytical Hierarchy Process (AHP), and Geographic Information Systems (GIS). The methodology design combines qualitative analysis, based on surveys of specialists, and quantitative analysis in a GIS environment, as a way to do a clear diagnosis of the current situation of the Island in relation to the disposal of existing dumps, and to been able to pinpoint the best sites for the installation of future sanitary landfills. The general objective of this research was, to build a model for decision support and sustainable development of São Tomé and Príncipe. Specific objectives are twofold: (i) to develop, through experimentation, a methodology and a model that is as close as possible to reality; (ii) to analyze the physical and legal suitability of landfills sites. The data collected and later analyzed through our model was classified as being of a social, demographic, economic, biophysical, legislative, political and citizen actions. The combined Geographic Information System (GIS) and Multicriteria Analysis proved to be an excellent decision support tool. In a first phase, the model allowed to reveal, from the diagnosis of the current situation of the disposition of the dumps, some spatial, legal, environmental and public health irregularities, inconsistencies and deficiencies; in a second phase, the model - with respect to the legal, social, economic, environmental and public health determinants - determines territorial units suitability (Low, Medium and High). Multicriteria weights were adjusted based on national and international experts’ surveys to levearage model robustness and in order to support decision making. Overall, results of the combined analysis of 14 (fourteen) criteria, respecting the legal, demographic projections and the potential production of waste, environmental and public health values, and economic consideration proved to be a good reality proxys. Results were mapped upon the following categories: Null, Low, Medium and High suitability, according to the weighted analysis of the criteria. Finally, for a better adjustment of the results, and for the areaspinpoint as High Aptitude, a spatial query was made based on the need of an area size criteria, such as: only sites with size areas equal to or greater than 12 ha were suitable for the implementation of the sanitary landfill

Application Potential of Fuzzy and Regression in Optimization of MRR and Surface Roughness during Machining of C45 Steel

In the machining industry, coolant has an important role due to their lubrication, cooling and chip removal functions. Using coolant can improve machining process efficiency, tool life, surface quality and it can reduce cutting forces and vibrations. However, health and environmental problems are encountered with the use of coolants. Hence, there has been a high demand for deep cryogenic treatment to reduce these harmful effects. For this purpose, −196 °C LN2 gas is used to improve machining performance. This study focuses on the prediction of surface roughness and material removal rate with cryogenically treated M2 HSS tool using fuzzy logic and regression model. The turning experiments are conducted according to Taguchi's L9 orthogonal array. Surface roughness and material removal rate during machining of C45 steel with HSS tool are measured. Cutting speed, feed rate, and depth of cut are considered as machining parameters. A model depended on a regression model is established and the results obtained from the regression model are compared with the results based on fuzzy logic and experiment. The effectiveness of regression models and fuzzy logic has been determined by analyzing the correlation coefficient and by comparing experimental results. Regression model gives closer values to experimentally measured values than fuzzy logic. It has been concluded that regression-based modeling can be used to predict the surface roughness successfully

Integrated nutrient management for improving crop yields, soil properties, and reducing greenhouse gas emissions

Recently, most agrarian countries have witnessed either declining or stagnant crop yields. Inadequate soil organic matter (SOM) due to the poor physical, chemical, and biological properties of the soil leads to an overall decline in the productivity of farmlands. Therefore, the adoption of integrated nutrient management (INM) practices is vital to revive sustainable soil health without compromising yield potential. Integrated nutrient management is a modified nutrient management technique with multifarious benefits, wherein a combination of all possible sources of plant nutrients is used in a crop nutrition package. Several studies conducted in various parts of the world have demonstrated the benefits of INM in terms of steep gain in soil health and crop yields and at the same time, reducing greenhouse gas emissions and other related problems. The INM practice in the cropped fields showed a 1,355% reduction in methane over conventional nutrient management. The increase in crop yields due to the adoption of INM over conventional nutrient management was as high as 1.3% to 66.5% across the major cropping systems. Owing to the integration of organic manure and residue retention in INM, there is a possibility of significant improvement in soil aggregates and microbiota. Furthermore, most studies conducted to determine the impact of INM on soil health indicated a significant increase in overall soil health, with lower bulk density, higher porosity, and water-holding capacity. Overall, practicing INM would enhance soil health and crop productivity, in addition to decreasing environmental pollution, greenhouse gas emissions, and production costs

Comparative Life Cycle Assessment of Packaging Systems for Extended Shelf Life Milk

The aim of this study is to carry out a comparative analysis of the environmental impact of different packaging systems used for extended shelf life milk. The analysis, carried out exploiting the life cycle assessment approach, takes into account the packaging manufacturing process, the food packaging process, the transport phases and the end-of-life management of the different packaging systems. The packaging end of-life is modelled by considering three possible options, such as recycling, thermo-valorization with energy recovery and landfill. One litre of extended shelf life milk is used as the reference unit, while multilayer cartons, polyethylene terephthalate bottles labelled with shrink sleeve film and high-density polyethylene bottles are analysed as the packaging types. The key characteristics of each component of the three packaging systems were either provided by packaging manufacturers or derived from data available in literature. The evaluation of the end-of-life impact was performed considering the Italian scenario, exploiting, in particular, the data provided by specific Italian consortia. Other data for the inventory analysis phase were extrapolated from the SimaPro databases (e.g. Ecoinvent or Plastic Europe Database). Cumulative energy demand and CML2001 were adopted as the impact assessment methods. The results obtained show that the multilayer carton system is the less environmentally impactful option for almost all the considered impact categories and that its environmental impacts are, on average, more than 12% lower than high-density polyethylene system and more than 34% lower than polyethylene terephthalate with shrink sleeve label

The Concile National of 1811: Napoleon, Gallicanism and the Failure of Neo-Conciliarism

The concile national of 1811 was, among, the greatest flashpoints in the struggle that pitted the Napoleonic Empire against the papacy. The concile deserves to be situated within more recent historiographical trends. This incident reveals much about the nature of Napoleonic imperialism and the Church’s distrust for the power of the state. This article puts forward the view that the failure of the concile national was not strategic but tactical. Several bishops were frustrated with the pope’s recalcitrance over episcopal investiture and fearful of schism. Their initial openness to neo-conciliarism turned to hostility when confronted with the state’s intolerance

Bibliometric Analysis of Research Trends in Rice Straw/Husk Reinforced Polymer Composites

Bibliometric research is statistical analysis of publications to identify the most influencing sources of research pertaining to a specific area of research. This paper presents an overview research on rice straw/husk (RS/RH) reinforced polymer composites by using the bibliometric indicators to establish the research framework and to identify the essential research. The relevant journals, authors, institutions and countries which have significantly contributed to research on RS/RH based composite is focused. The bibliometric data is generated through Scopus database. It is observed that the number of publications on characterization of RS/RH based composites are consistently increasing over the last few years along with their citations. The major focus of the researchers is to determine the mechanical (tensile and flextural) and thermal properties of these composites. The countries which are supporting the research of this nature through funding are Malaysia, Europe and USA. The number of publications on material characterization of RS/RH composites has increased almost linearly in the recent years. About 88.90% of the articles which are published in the journals are related to engineering, material science and agricultural domain

Stochastic growth of cloud droplets by collisions during settling

In the last stage of droplet growth in clouds which leads to drizzle formation, larger droplets begin to settle under gravity and collide and coalesce with smaller droplets in their path. In this article, we shall deal with the simplified problem of a large drop settling amidst a population of identical smaller droplets. We present an expression for the probability that a given large drop suffers a given number of collisions, for a general statistically homogeneous distribution of droplets. We hope that our approach will serve as a valuable tool in dealing with droplet distribution in real clouds, which has been found to deviate from the idealized Poisson distribution due to mechanisms such as inertial clustering

ROBOT OPERATED PAINTING MACHINE USING SYSTEM SIMULATION

This paper presents the development of spray painting robot controlled machine through computer simulation. The operations of robot and spray was controlled by system and operated by pneumatic controller. To operate the robot, program was written using VB. The spray was utilized to paint the surfaces which were not feasible to operate by humans. Signals are processed using a relay in external electronic circuit. This will control any operations of the device. The robot can move forward, backward, left and right. This device can be used to paint any vehicle in any place in future this can be implemented with artificial intelligence which can paint automaticall