Potential impact of load curtailment on the day-ahead Iberian market : a preliminary analysis

ABSTRACT: Demand response (DR) in electricity markets may offer a variety of financial and operational benefits. Typically, customers respond to DR events by adopting curtailment and shifting strategies. This article focuses on the former strategy and assumes that consumers are encouraged to avoid consuming electricity during specific hours of a 24 h day, because the energy price is above a given threshold. It presents a study on the Iberian market, conducted with the help of an agent-based simulation tool, called MATREM. The results are very favorable to the adoption of the load curtailment strategy (as a consequence of the enrollment in different DR programs).info:eu-repo/semantics/publishedVersio

Developing a site-conditions map for seismic hazard Assessment in Portugal

The evaluation of site effects on a broad scale is a critical issue for seismic hazard and risk assessment, land use planning and emergency planning. As characterization of site conditions based on the shear-wave velocity has become increasingly important, several methods have been proposed in the literature to estimate its average over the first thirty meters (Vs30) from more extensively available data. These methods include correlations with geologic-geographic defined units and topographic slope. In this paper we present the first steps towards the development of a site–conditions map for Portugal, based on a regional database of shear-wave velocity data, together with geological, geographic, and lithological information. We computed Vs30 for each database site and classified it according to the corresponding geological-lithological information using maps at the smallest scale available (usually 1:50000). We evaluated the consistency of Vs30 values within generalized-geological classes, and assessed the performance of expedient methodologies proposed in the literature

GeMs/GSAOI observations of La Serena 94: an old and far open cluster inside the solar circle

Physical properties were derived for the candidate open cluster La Serena 94, recently unveiled by the VVV collaboration. Thanks to the exquisite angular resolution provided by GeMS/GSAOI, we could characterize this system in detail, for the first time, with deep photometry in JHK$_{s}$ - bands. Decontaminated JHK$_{s}$ diagrams reach about 5 mag below the cluster turnoff in H. The locus of red clump giants in the colour - colour diagram, together with an extinction law, was used to obtain an average extinction of $A_V =14.18 \pm 0.71$. The same stars were considered as standard - candles to derive the cluster distance, $8.5 \pm 1.0$ kpc. Isochrones were matched to the cluster colour - magnitude diagrams to determine its age, $\log{t(yr)}=9.12\pm 0.06$, and metallicity, $Z=0.02\pm0.01$. A core radius of $r_{c}=0.51\pm 0.04$ pc was found by fitting King models to the radial density profile. By adding up the visible stellar mass to an extrapolated mass function, the cluster mass was estimated as $M=(2.65\pm0.57) \times 10^3$ M$_{\odot}$, consistent with an integrated magnitude of $M_{K}=-5.82\pm0.16$ and a tidal radius of $r_{t}=17.2\pm2.1$ pc. The overall characteristics of La Serena 94 confirm that it is an old open cluster located in the Crux spiral arm towards the fourth Galactic quadrant and distant $7.30\pm 0.49$ kpc from the Galactic centre. The cluster distorted structure, mass segregation and age indicate that it is a dynamically evolved stellar system.Comment: 16 pages, 24 figures, 2 Tables, accepted by MNRAS; corrected typo

Potencial de radão em setores da Zona de Ossa Morena

O radão é considerado a maior fonte de exposição a radiação ionizante dentro de habitações, motivo pelo qual é essencial conhecer a sua distribuição espacial. Este trabalho tem como objetivo o estudo do potencial de radão de rochas aflorantes na Zona de Ossa Morena (ZOM). Para tal, foram colhidas 132 amostras nos principais setores da ZOM. Os resultados obtidos demonstram a enorme variabilidade das propriedades radiológicas e físicas nas litologias analisadas. As atividades de 226Ra e de radão são, em média, inferiores nas rochas calco-silicatadas e rochas ígneas básicas e ultrabásicas e superiores nas rochas graníticas e sienitos. Os metassedimentos, rochas de alto grau metamórfico, granodioritos, dioritos e tonalitos apresentam atividades de 226Ra e de radão intermédias e similares entre si. A porosidade, que determina a capacidade de migração de radão no meio, é superior nos metassedimentos e inferior nas rochas ígneas, independentemente do seu caráter

Sanitizing the fortress: protection of ant brood and nest material by worker antibiotics

Social groups are at particular risk for parasite infection, which is heightened in eusocial insects by the low genetic diversity of individuals within a colony. To combat this, adult ants have evolved a suite of defenses to protect each other, including the production of antimicrobial secretions. However, it is the brood in a colony that are most vulnerable to parasites because their individual defenses are limited, and the nest material in which ants live is also likely to be prone to colonization by potential parasites. Here, we investigate in two ant species whether adult workers use their antimicrobial secretions not only to protect each other but also to sanitize the vulnerable brood and nest material. We find that, in both leaf-cutting ants and weaver ants, the survival of the brood was reduced and the sporulation of parasitic fungi from them increased, when the workers nursing them lacked functional antimicrobial-producing glands. This was the case for both larvae that were experimentally treated with a fungal parasite (Metarhizium) and control larvae which developed infections of an opportunistic fungal parasite (Aspergillus). Similarly, fungi were more likely to grow on the nest material of both ant species if the glands of attending workers were blocked. The results show that the defense of brood and sanitization of nest material are important functions of the antimicrobial secretions of adult ants and that ubiquitous, opportunistic fungi may be a more important driver of the evolution of these defenses than rarer, specialist parasites

Novos dados petrográficos, geoquímicos e isotópicos sobre a área de concessão de Boa Fé (Montemor-o-Novo, Zona de Ossa-Morena)

A área do estudo situa-se na Zona de Cisalhamento de Montemor-o-Novo (Maciço de Évora, Zona de Ossa-Morena - ZOM). O trabalho incidiu sobre amostras de metassedimentos e metabasitos da Série Negra (Ediacarano), bem como de granitos tardi-variscos. Os metassedimentos vão de micaxistos a paragnaisses com a associação, de pico metamórfico, Qz+Pl+Bt+Ms+Opq ±Tur±Sil±Crd+Zrn. Os metabasitos são anfibolitos com paragénese Pl+Hbl+Qz+Mag+Ilm±Bt. Quer nos metassedimentos quer nos metabasitos, existem testemunhos de duas fases de deformação importantes, sendo uma xistosidade de crenulação a estrutura mais penetrativa. Aquelas duas fases de deformação dúctil deverão corresponder às fases variscas D1 e D2 do autóctone da ZOM. Ocorreu ainda deformação posterior, testemunhada por kinks e processos de subgranulação e recristalização afetando alguns grãos em zonas confinadas às proximidades imediatas de fraturas tardias, a qual deverá relacionar-se com a fase D3. Os granitos tardi-variscos são fortemente peraluminosos, tendo como minerais mais abundantes quartzo, microclina, plagioclase sódica e moscovite. Como acessórios ocorrem biotite, zircão, apatite, opacos, turmalina e silimanite. Em termos isotópicos, os valores de εSr320Ma variam entre +93 e +182, enquanto a gama de valores para εNd320Ma vai de -6.7 a -9.0, compatíveis com um forte contributo de anatexia dos metassedimentos da Série Negra na génese dos magmas que deram origem aos granitos tardi-variscos.The study area is located within the Montemor-o-Novo Shear Zone (Évora Massif, Ossa-Morena Zone - OMZ). The analysed samples are of metasediments and metabasites of the Série Negra lithostratigraphic unit (Ediacaran) and of late-Variscan granites. The metasediments are micaschists to paragneisses displaying Qz+Pl+Bt+Ms+Opq±Tur±Sil±Crd+Zrn as peak metamorphic assemblage. The metabasites are amphibolites displaying the paragenesis Pl+Hbl+Qz+Mag+Ilm±Bt. Microstructures observed in both types of metamorphic rocks document two major ductile deformation phases. The most penetrative tectonic anisotropy is a crenulation schistosity. Those major deformation phases probably correspond to the Variscan D1 and D2, previously recognized in the autochthon of the OMZ. There is also evidence for a later deformation stage, likely related to the Variscan D3: some grains, in narrow zones adjacent to late fractures, show kinks or were affected by subgranulation and recrystallization. The studied late-Variscan granites are strongly peraluminous, and have quartz, microcline, Na-plagioclase and muscovite as the most abundant minerals. Biotite, zircon, apatite, opaques, tourmaline and sillimanite occur as accessory minerals. Considering isotope geochemistry, εSr320Ma varies between +93 and +182, whilst the εNd320Ma values go from -6.7 to -9.0. These data can be explained by a strong involvement of anatexis of the Série Negra metasediments in the genesis of the granitic magmas

Digital technologies in architecture and engineering: Exploring an engaged interaction within curricula

This chapter focuses on the development and adoption of new Multimedia, Computer Aided Design, and other ICT technologies for both Architecture and Computer Sciences curricula and highlights the multidisciplinary work that can be accomplished when these two areas work together. We describe in detail the addressed educational skills and the developed research and we highlight the contributions towards the improvements of teaching and learning in those areas. We discuss in detail the role of Digital technologies, such as Virtual Reality, Augmented Reality, Multimedia, 3D Modelling software systems, Design Processes and its evaluation tools, such as Shape Grammar and Space Syntax, within the Architecture curricula.info:eu-repo/semantics/acceptedVersio