Nossa Senhora da Piedade - Piéta

O trabalho que se apresenta centra-se no domínio da Conservação e Restauro do Património, no âmbito do estudo e conservação da Nossa Senhora da Piedade, propriedade da Irmandade de Nossa Senhora do Livramento de Angra do Heroísmo, Ilha Terceira. O presente estudo está inserido no estágio de Conservação e Restauro de escultura em madeira policromada, sendo nele abordada a contextualização da obra na sua dimensão artística e histórica, os materiais e técnicas do suporte e camadas superficiais, o seu estado de conservação, uma metodologia para a posterior intervenção e por fim um estudo para o possível plano de manutenção do local de exposição

Calibration of the Gipps Car-following Model Using Trajectory Data

One of the most important tasks in the microscopic simulation of traffic flow, assigned to the car following sub-model, is the modelling of the longitudinal movement of vehicles. The calibration of a car-following model is usually done at an aggregated level, using macroscopic traffic stream variables (speed, flow, density). There is an interest in calibration procedures based on disaggregated data. However, obtaining accurate trajectory data is a real challenge. This paper presents a low-cost procedure to calibrate the Gipps car-following model. The trajectory data is collected with a car equipped with a datalogger and a LIDAR rangefinder. The datalogger combines GPS and accelerometers data to provide accurate speed and acceleration measurements. The LIDAR measures the distances to the leading or following vehicle. Two alternative estimation methods were tested: the first follows individual procedures that explicitly account for the physical meaning of each parameter; the second formulates the calibration as an optimization problem: the objective function is defined so as to minimize the differences between the simulated and real inter-vehicle distances; the problem is solved using an automated procedure based on a genetic algorithm. The results show that the optimization approach leads to a very accurate representation of the specific modeled situation but offers poor transferability; on the other hand, the individual estimation provides a satisfactory fit in a wide range of traffic conditions and hence is the recommended method for forecasting purposes

Das rotundas convencionais às turborotundas

O conceito de turborotunda surgiu recentemente, na Holanda, como solução alternativa à rotunda normal com múltiplas vias, com o objetivo de resolver os problemas de segurança relacionados com entrecruzamentos no anel de circulação. Embora sejam poucos os estudos científicos que abordam esta matéria, a experiência estrangeira mostra que esta solução assegura elevados níveis de desempenho geral. Nesse contexto, o presente artigo apresenta o conceito de turborotunda e as suas potencialidades comparativamente à rotunda normal, quer em termos de segurança quer de capacidade. Complementarmente, são apresentadas algumas regras básicas de apoio ao seu dimensionamento geométrico e à estimação de capacidades

Sustainability: Who is Driving it?

Sustainability is a multifaceted concept which is presently ubiquitous in modern society. As a result, it is difficult for a more definite definition of what sustainability is as it relies on the fact that such a concept has been socially constructed throughout the twentieth century. A brief description of the milestones around the debate on sustainability until the 2000s attempts to highlight the fact that sustainability, as a social construct, has been evolved in response to social, economic and environmental pressures. Following that, the role of consumers and business will be analysed. The first is analysed from a behavioural consumption perspective where a short literature review has attempted to put into perspective the theoretical elements explaining reasons consumers behave, or not, in a more pro-environmental manner. The latter is analysed from the perspective of businesses actively seeking to improve their sustainability positions in the UK market. It is proposed that businesses, rather than consumers, are the principal stakeholders which act as spearheads enabling transformations in business practices that would enable them to attain higher levels of sustainability gains. Businesses do so in order to satisfy some customers, pressure groups and the government, but in so doing reap advantages such as increased efficiency, reduced cost and consequently higher profits. Cases of large food manufacturers in the UK are described regarding the awareness of such businesses to take their sustainability agenda further. The motivation of such businesses is mainly profit-making, to improve their competitive position in a mature market where growth is marginal through differentiation. However, in operating in such an environment, great demand is put on suppliers which have to comply with the industry’s strict standards. Finally, recommendations are made for businesses in emerging markets with an interest in entering the export sector. For businesses in emerging markets, it is of great relevance to understand the food supply chains abroad since the transmission of knowledge, the adhering to standards and the consumers impose challenges that need to be addressed

Healthcare system delay and utilization in tuberculosis patients in Portuguese high-incidence region

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Lithium Ferrite: Synthesis, Structural Characterization and Electromagnetic Properties

Lithium ferrite (LiFe5O8) is a cubic ferrite, belongs to the group of soft ferrite materials with a square hysteresis loop, with high Curie temperature and magnetization. The spinel structure of LiFe5O8 has two crystalline forms: ordered, β-LiFe5O8 (Fd3m space group) and disordered, α-LiFe5O8 (P4132/P4332 space group). It has numerous technological applications in microwave devices, computer memory chip, magnetic recording, radio frequency coil fabrication, transformer cores, rod antennas, magnetic liquids among others. It is also a promising candidate for cathode in rechargeable lithium batteries. In this work, the dc electrical conductivity, the impedance spectroscopy and the magnetization of Li2O-Fe2O3 powders, with [Li]/[Fe]=1/5 (mol), heat-treated at several temperatures, are studied and related to their structure and morphology. The structural data were obtained by X-ray diffraction and Raman spectroscopy, and the morphology by scanning electron microscopy. The impedance spectroscopy was analysed in function of temperature and frequency, and it was observed that the dielectric properties are highly dependent on the microstructure of the samples. The dc magnetic susceptibility was recorded with a vibrating sample magnetometer, under zero field cooled and field cooled sequences, between 5-300 K. Typical hysteresis curves were obtained and the saturation magnetization increases with increase in heat-treatment temperature

Impacts of species misidentification on species distribution modeling with presence-only data

Spatial records of species are commonly misidentified, which can change the predicted distribution of a species obtained from a species distribution model (SDM). Experiments were undertaken to predict the distribution of real and simulated species using MaxEnt and presence-only data “contaminated” with varying rates of misidentification error. Additionally, the difference between the niche of the target and contaminating species was varied. The results show that species misidentification errors may act to contract or expand the predicted distribution of a species while shifting the predicted distribution towards that of the contaminating species. Furthermore the magnitude of the effects was positively related to the ecological distance between the species’ niches and the size of the error rates. Critically, the magnitude of the effects was substantial even when using small error rates, smaller than common average rates reported in the literature, which may go unnoticed while using a standard evaluation method, such as the area under the receiver operating characteristic curve. Finally, the effects outlined were shown to impact negatively on practical applications that use SDMs to identify priority areas, commonly selected for various purposes such as management. The results highlight that species misidentification should not be neglected in species distribution modeling

Impacts of species misidentification on species distribution modeling with presence-only data

Spatial records of species are commonly misidentified, which can change the predicted distribution of a species obtained from a species distribution model (SDM). Experiments were undertaken to predict the distribution of real and simulated species using MaxEnt and presence-only data “contaminated” with varying rates of misidentification error. Additionally, the difference between the niche of the target and contaminating species was varied. The results show that species misidentification errors may act to contract or expand the predicted distribution of a species while shifting the predicted distribution towards that of the contaminating species. Furthermore the magnitude of the effects was positively related to the ecological distance between the species’ niches and the size of the error rates. Critically, the magnitude of the effects was substantial even when using small error rates, smaller than common average rates reported in the literature, which may go unnoticed while using a standard evaluation method, such as the area under the receiver operating characteristic curve. Finally, the effects outlined were shown to impact negatively on practical applications that use SDMs to identify priority areas, commonly selected for various purposes such as management. The results highlight that species misidentification should not be neglected in species distribution modeling

Novos modelos de estimação de capacidades em rotundas

Este artigo apresenta uma análise comparativa de modelos de capacidades aplicados a rotundas, suportada por uma base de dados real. O estudo demonstra que os modelos convencionais – TRL e Siegloch – são incapazes de produzir estimativas fiáveis em toda a gama de variação dos fluxos conflituantes. Por outro lado, o modelo de Hagring, associado a um novo método de parametrização dos intervalos nas correntes prioritárias, permite diferenciar as condições de circulação nas diferentes vias de entrada e de circulação e revela-se capaz de estimar com fiabilidade a capacidade de soluções sujeitas a repartições desequilibradas do tráfego direcional