Revisiting Complex Moments For 2D Shape Representation and Image Normalization

When comparing 2D shapes, a key issue is their normalization. Translation and scale are easily taken care of by removing the mean and normalizing the energy. However, defining and computing the orientation of a 2D shape is not so simple. In fact, although for elongated shapes the principal axis can be used to define one of two possible orientations, there is no such tool for general shapes. As we show in the paper, previous approaches fail to compute the orientation of even noiseless observations of simple shapes. We address this problem. In the paper, we show how to uniquely define the orientation of an arbitrary 2D shape, in terms of what we call its Principal Moments. We show that a small subset of these moments suffice to represent the underlying 2D shape and propose a new method to efficiently compute the shape orientation: Principal Moment Analysis. Finally, we discuss how this method can further be applied to normalize grey-level images. Besides the theoretical proof of correctness, we describe experiments demonstrating robustness to noise and illustrating the method with real images.Comment: 69 pages, 20 figure

An in-reachability based classification of invariant synchrony patterns in weighted coupled cell networks

This paper presents an in-reachability based classification of invariant synchrony patterns in Coupled Cell Networks (CCNs). These patterns are encoded through partitions on the set of cells, whose subsets of synchronized cells are called colors. We study the influence of the structure of the network in the qualitative behavior of invariant synchrony sets, in particular, with respect to the different types of (cumulative) in-neighborhoods and the in-reachability sets. This motivates the proposed approach to classify the partitions into the categories of strong, rooted and weak, according to how their colors are related with respect to the connectivity structure of the network. Furthermore, we show how this classification system acts under the partition join ($\vee$) operation, which gives us the synchrony pattern that corresponds to the intersection of synchrony sets.Comment: 48 pages, 19 figures, 3 table

Modelação matemática do contágio da gripe pessoa a pessoa

Este trabalho tem como principal objetivo o estudo da propagação do vírus da gripe a partir da simulação do modelo SIR incorporando o comportamento estocástico. As simulações têm em conta diferentes números de contactos adequados à transmissão da gripe (σ) e diferentes taxas de vacinação (ν) para termos de comparação, estas simulações foram efetuadas no software MatLab.info:eu-repo/semantics/publishedVersio

Dynamic Interdomain Network Slicing for verticals in the 5Growth project

Proceedings of: IEEE Conference on Network Function Virtualization and Software Defined Networks (NFV-SDN), 9-11 Nov. 2021, Heraklion, Greece.This paper proposes and validates a Interdomain Network Slicing framework for verticals, allowing them to directly participate in the establishment and control of end-to-end Communication Services deployment across multiple inter-operator domains. The framework progresses the means made available by different standards and research initiatives to enhance service requesting and provisioning interfaces for the stakeholders involved, namely operators and verticals. The framework is validated under two different use cases, showcasing effective end-to-end service instantiation and a first assessment towards dynamic service modification capability.This work has been supported by EC H2020 5GPPP 5Growth project (Grant 856709)

ANGULAR KINEMATICS AND JOINT MOMENTS ANALYSIS IN LOWER LIMB AND PELVIS DURING GAIT IN SAGITTAL PLANE IN PREGNANT WOMEN

This study compared sagittal plane lower limb range of motion (ROM) and joint moments of force (Mf) during gait in pregnant (second trimester) and non-pregnant women. Kinematic data were collected with an optoelectronic motion capture system (Qualysis, Ocqus 300) synchronized with two force platforms (Kistler AG, Winterthur, Switzerland) which collected ground reaction force values. The study revealed that the gait pattern in the second trimester of pregnancy is similar to the non-pregnant women pattern, in what concerns to the variables studied. Lower dorsiflexion and higher plantar flexion angles in the ankle joint in pregnant women, and higher values of hip flexion for the same group, were observed. With respect to the joint moments of force, there were higher knee flexor and hip extensor peak moments in pregnant women

Differences in chemical composition and antioxidant activity of three propolis samples collected in the same apiary

Financial support provided by FCT (PD/BD/128276/2017), under the Doctoral Programme Agrichains - PD/00122/2012

Contribución para la caracterización florístico-ambiental del Norte de Portugal

En el presente trabajo se hace mención a diferentes taxones específicos e infraespecíficos con distribuciones diversas en el territorio portugués continental. En este sentido, la intensa variabilidad geomorfológica y la intrincada bioclimatología del Norte de Portugal constituyen, ambos, factores ambientales decisivos para comprender el comportamiento florístico de esta parte del país. Los taxones analizados en esta aportación son: Teucrium salviastrum Trigonella polyceratia subsp. amandiana, Ononis viscosa subsp. breviflora var. breviflora, Ononis viscosa subsp. pedroi, Digitalis amandiana, Myosotis welwistchii y Myosotis secunda. De modo a poder contribuir eficientemente en la gestión de la riqueza florística, se procede a la aplicación de una rutina programática multivariada, basada en un sistema de información geográfico (SIG), a partir del cual cada uno de los taxones estudiados es georeferenciado sobre cartografía ambiental (confeccionada y publicada por el Instituto para a Conservação da Naturaza, del Ministerio del Ambiente portugués). Los resultados obtenidos confirman el efecto gradual de transición entre el área de influencia bioclimática atlántica y la mediterránea, ambas determinantes para comprender el comportamiento florístico del Norte de Portugal.Several specific and infraspecific taxa with different occurrences in the continental portuguese area are referred in the present work. In the light of these behaviours, the climatic and geomorphological variability of the North of Portugal has been important environmental factors to explain the floristic diversity in this part of the country. In this case, the taxa analysed are Teucrium salviastrum Trigonella polyceratia subsp. amandiana, Ononis viscosa subsp. breviflora var. breviflora, Ononis viscosa subsp. pedroi, Digitalis amandiana, Myosotis welwistchii and Myosotis secunda. Because of the appropriate management of the floristic richness, a multivariate statistic routine is applied on a Geographical Informatic System (GIS) the chorological, geomorphological and climatic characterization for each one are described in this paper. The geological substrate and the altitudinal classes are focused for the geomorphological approach, as well as two biogeographic classifications are used to correlate the occurrence of the taxa and their bioclimatic preferences. In the light of this analytical scheme, every taxa is geo-referenced upon an environmental cartography (elaborated by the Instituto para a Conservação da Naturaza). The results obtained are pointing out the floristic progressive differentiation between the atlantic bioclimatic influence and the mediterranean one, both bioclimatic influences decisive to understand the floristic behaviour of the North of Portugal

Conservation Management of EU Priority Habitats after Collapse of Traditional Pastoralism: Navigating Socioecological Transitions in Mountain Rangeland

Agricultural abandonment is a major driver of change in rural landscapes. Assumed to provide beneficial results to the environment and the conservation of biota, rural abandonment triggers landscape and biotic homogenization and loss of valuable species and habitats. This article focuses on the ecological effects and conservation challenges of shifts in extensive grazing regimes on marginal pastureland of Mediterranean mountains. We conceptualize a navigated socioecological transition toward conservation-oriented management after the collapse of historical land systems. The article provides examples from the LIFE+ project “Higro,” developed in mountainous protected areas in Portugal, of how management for conservation could sustain disturbance-dependent habitats. We argue that actively and regularly managing large habitat areas should be envisaged as a short-term approach to limit the immediate effects of rural abandonment. A gradual integration of conservation targets with other activities in changing rural economies is necessary to foster long-term conservation of species and habitats, building on the link between conservation-oriented habitat management and ecosystem services in rural landscapes. Conservation goals should run alongside recovery of social systems and innovation applied to traditional sources of income. This parallel development would contribute to building up social-ecological resilience by maintaining a diversity of social and ecological capital in rural areas.info:eu-repo/semantics/publishedVersio

Canopy insect herbivores in the Azorean Laurisilva forests: key host plant species in a highly generalist insect community

Copyright © ECOGRAPHY 2005.This article explores patterns of insect herbivore distribution in the canopy of the Laurisilva forests on seven islands in the Azores archipelago. To our knowledge, this is one of the first extensive studied of this type in tree or shrub canopies of oceanic island ecosystems. One of the most frequently debated characteristics of such ecosystems is the likely prevalence of vague, ill-defined niches due to taxonomic disharmony, which may have implications for insect-plant interactions. For instance, an increase in ecological opportunities for generalist species is expected due to the lack of predator groups and reduced selection for chemical defence in host plants. The following two questions were addressed: 1) Are specialists rare species, and insect herbivore species randomly distributed among host plant species in the Azores? 2) Are the variances in insect herbivore species composition, frequency and richness explained by host plants or by regional island effects? We expect a proportional distribution of herbivore species between host plants, influenced by host frequency and distinct island effects; otherwise, deviation from expectation might suggest habitat preference for specific host tree crowns. Canopy beating tray samples were performed on seven islands, comprising 50 transects with 1 to 3 plant species each (10 replicates per species), giving 1320 samples from ten host species trees or shrubs in total. From a total of 129 insect herbivore species, a greater number of herbivore species was found on Juniperus brevifolia (s=65) and Erica azorica (s=53). However, the number of herbivore species per individual tree crown was higher for E. azorica than for any other host, on all islands, despite the fact that it was only the fourth more abundant plant. In addition, higher insect species richness and greater insect abundance were found on the trees of Santa Maria Island, the oldest in the archipelago. Insect species composition was strongly influenced by the presence of E. azorica, which was the only host plant with a characteristic fauna across the archipelago, whereas the fauna of other plant crowns was grouped by islands. The great insect occurrence on E. azorica reflects strong habitat fidelity, but only four species were clearly specialists. Our findings indicate a broadly generalist fauna. The simplicity of Azorean Laurisilva contributed to the understanding of insect-plant mechanisms in canopy forest habitats