A Fractal Interaction Model for Winding Paths through Complex Distributions: Application to Soil Drainage Networks

Water interacts with soil through pore channels putting mineral constituents and pollutants into solution. The irregularity of pore boundaries and the heterogeneity of distribution of soil minerals and contaminants are, among others, two factors influencing that interaction and, consequently, the leaching of chemicals and the dispersion of solute throughout the soil. This paper deals with the interaction of irregular winding dragging paths through soil complex distributions. A mathematical modelling of the interplay between multifractal distributions of mineral/pollutants in soil and fractal pore networks is presented. A Ho¨lder path is used as a model of soil pore network and a multifractal measure as a model of soil complex distribution, obtaining a mathematical result which shows that the Ho¨lder exponent of the path and the entropy dimension of the distribution may be used to quantify such interplay. Practical interpretation and potential applications of the above result in the context of soil are discussed. Since estimates of the value of both parameters can be obtained from field and laboratory data, hopefully this mathematical modelling might prove useful in the study of solute dispersion processes in soil

The Portuguese real exchange rate, 1995-2010 : competitiveness or price effects?

We disentangle the extent to which the real exchange rate appreciation in Por- tugal during 1995-2010 re ected the emergence of wage-productivity misalignments or, instead, changes in the relative price of tradable and non-tradable goods. The available data suggests that the latter e ect dominated at the aggregate level. The evidence is consistent with the view that the external imbalance that character- ized the Portuguese economy during the 1990s and early 2000s was triggered by the liberalization of capital ows, and not by dysfunctional wage setting institu- tions. Using the Fundamental Equilibrium Exchange Rate approach, we nd that recent oil price shocks played an important role in explaining the real exchange rate overvaluation in Portugal.COMPETE; QREN; FEDER; Fundação para a Ciência e a Tecnologia (FCT

Global diversity of coastal cephalopods: hotspots and latitudinal gradients

Tese de mestrado em Ecologia Marinha, apresentada à Universidade de Lisboa, através da Faculdade de Ciências, 2017A presente dissertação visa identificar, pela primeira vez, os hotspots globais de diversidade de cefalópodes costeiros, nomeadamente, de chocos (famílias Sepiidae, Sepiolidae, Sepiadariidae e Idiosepiidae), lulas (famílias Loliginidae) e polvos (família Octopodidae) e avaliar os correspondentes gradientes latitudinais de riqueza específica (GLRS). Neste âmbito, foi criada uma base de dados de presenças/ausências, de acordo com as Ecoregiões Marinhas do Mundo, na qual o Oceano Pacífico surge como sendo o mais diverso (com 212 espécies), seguido do Índico (com 151 espécies) e do Atlântico (com 103 espécies). Em contraste, os Oceanos Ártico (com 13 espécies) e Antártico (com 7 espécies) revelaram-se os menos diversos. Das 232 ecoregiões consideradas, o maior valor de diversidade específica foi obtido na ecorregião da Corrente Kuroshio Central (CKC), com 64 espécies, seguido do Mar da China Oriental (MCO), com 59 espécies, e das Filipinas (F), com 48 espécies. Advogo que a localização destes hotspots se encontra relacionada com as teorias de “centro de origem”, “centro de sobreposição” ou “centro de acumulação” postuladas para a região do Arquipélago Indo-Australiano, tendo em conta as particulares condições de produtividade associadas aos dinâmicos sistemas de upwelling próximos da CKC e da ECS. Relativamente à relação entre latitude e diversidade, os picos de diversidade de cefalópodes variaram entre oceanos e apenas as lulas exibiram uma distribuição unimodal. Por outro lado, os chocos, polvos e a classe Cephalopoda revelaram distribuições bimodais, sendo que o maior pico de diversidade se encontrou sempre no hemisfério norte. Defendo que o padrão unimodal das lulas possa ser o resultado do efeito de disponibilidade energética (temperatura à superfície do mar) na fisiologia dos organismos, tal como proposto pela “hipótese energética do ambiente”. Em contrapartida, a generalizada distribuição bimodal poderá estar associada à produtividade oceânica, tal como defendido pela “hipótese espécies-produtividade”, uma vez que áreas altamente produtivas tendem a estar associadas a latitudes temperadas. Em síntese, estes resultados realçam a noção de que a forma e simetria do GLRS não são universais e que não existe um só preditor causal que explique a localização dos hotspots e dos picos de diversidade latitudinal dentro do mesmo taxa.The present dissertation aimed to identify, for the first time, the global hotspots of coastal cephalopod diversity, namely cuttlefishes (families Sepiidae, Sepiolidae, Sepiadariidae and Idiosepiidae), squids (family Loliginidae) and octopuses (family Octopodidae), and assess their latitudinal gradient of species richness (LGRS). I created a presence/absence database, according to Marine Ecoregions of the World, which revealed that the most diverse ocean was the Pacific (with 212 species), followed by the Indian (151 species) and Atlantic (103 species) Oceans. The least diverse were the Artic (13 species) and Southern (7 species) Oceans. Within the 232 ecoregions considered, the highest diversity value was reached in the Central Kuroshio Current (CKC) ecoregion, with 64 species, followed by the East China Sea (ECS, 59 species) and the Eastern Philippines (EP, 48 species). I advocate that these hotspots are linked to the “centre of origin”, “centre of overlap” or “centre of accumulation” hypotheses postulated for the Indo-Australian Archipelago region, together with the particular productivity-rich conditions associated with upwelling system dynamics near CKC and ECS. Regarding the association between latitude and diversity, cephalopod peak of diversity varied among oceans, and only the squids showed a unimodal distribution with latitude. In opposition, cuttlefish, octopods and Cephalopoda revealed bimodal distributions, always with the major peak of diversity in the north hemisphere. I argue that the squid unimodal pattern may be a result of the effect of energy availability (sea surface temperature) in the organism’s physiology, as proposed by the “ambient energy hypothesis”. On the other hand, the widespread bimodal distributions may be linked to ocean productivity (i.e. the “species-productivity hypothesis”) given that highly productive areas tend to be associated with temperate latitudes. Summing up, these findings highlight the notion that the shape and symmetry of LGRS are not universal and there are no single causal predictors to explain hotspot and latitudinal zenith locations within the same taxa

Impact of the Fourth Industrial Revolution on the Health Sector: A Qualitative Study

Objectives: The Fourth Industrial Revolution is changing the way health is understood, transforming the methods of treatment and diagnosis as well as the relationship between health professionals and patients and altering the management and organization of health systems. The main objective of this study was to explore the impact that the Fourth Industrial Revolution is having on the health sector. Methods: Conducting interviews consisting of four questions with 10 professionals who had experience working in the health sector to gain their insights and to obtain information to meet the general objective of the study as well as its specific objectives. Results: From the analysis of the respondents’ responses, it was possible to create five dimensions developed by the topics most addressed by respondents, namely, impact on healthcare efficiency and effectiveness, impact on government action, impact on human resources, impact on health system organization, and financial impact on the health sector. Conclusions: Although the Fourth Industrial Revolution is still at an early stage, it has been concluded that it is having a major positive impact on the health sector. For the effective and efficient implementation of these disruptive technologies, a global interaction between governments, health professionals, stakeholders, and society is essential to make this change possible.info:eu-repo/semantics/publishedVersio

Computer simulation of the interplay between fractal structures and surrounding heterogeneous multifractal distributions. Applications

In a large number of physical, biological and environmental processes interfaces with high irregular geometry appear separating media (phases) in which the heterogeneity of constituents is present. In this work the quantification of the interplay between irregular structures and surrounding heterogeneous distributions in the plane is made For a geometric set image and a mass distribution (measure) image supported in image, being image, the mass image gives account of the interplay between the geometric structure and the surrounding distribution. A computation method is developed for the estimation and corresponding scaling analysis of image, being image a fractal plane set of Minkowski dimension image and image a multifractal measure produced by random multiplicative cascades. The method is applied to natural and mathematical fractal structures in order to study the influence of both, the irregularity of the geometric structure and the heterogeneity of the distribution, in the scaling of image. Applications to the analysis and modeling of interplay of phases in environmental scenarios are given

Computer Simulation of Packing of Particles with Size Distributions Produced by Fragmentation Processes

Fragmentation schemes inspired by theoretical results and conjectures of Kolmogorov are applied to produce particle size distributions of different natures, depending on fragmentation parameters. A two-dimensional computer simulation method of packing is applied to the resulting distributions and the void fraction is evaluated. The relationship between the void fraction and characteristic parameters of the fragmentation process is studied

ALGORITHM FOR THE PROJECTION OF FOREST GROWTH AND PRODUCTION

The modeling of forest growth and production is an essential tool for forestry management because it allows us to perform simulations and project forest biometric variables in the future, thus assisting in stock planning and economic analyses. In this work, a growth and production model by diameter distribution was proposed with the application of the Weibull function based on the recovery of parameters through simplified functions between the forest attributes and the parameters of the Weibull function. The algorithm was developed in Excel’s VBA language. Validation was performed with data from the Continuous Forest Inventory (CFI) in a stand of Khaya grandifoliola and in rows of Eucalyptus spp. in the ILPF system, which were ordinarily organized into seven date combinations, from the most distant from to the closest to the projection date. The results were evaluated by the percentage standard error (SE%) applied to the projected and observed volumes and by the Kolmogorov‒Smirnov test applied to the diameter distributions to verify adherence. It was possible to identify an exact relationship for parameter c of the Weibull function as a function of the percentiles and for parameter b, improving the parameter recovery method. Another methodological improvement was the use of maximum diameter and maximum height for age to adjust the hypsometric function. The algorithm presented results for total volume with errors up to 20% in 85% of the tests

A packing computational method relating fractal particle size distribution and void fraction in granular media

The study of granular systems is of great interest to many fields of science and technology. The packing of particles affects to the physical properties of the granular system. In particular, the crucial influence of particle size distribution (PSD) on the random packing structure increase the interest in relating both, either theoretically or by computational methods. A packing computational method is developed in order to estimate the void fraction corresponding to a fractal-like particle size distribution