197 research outputs found
Evaluación de la pesquerías con líneas de mano en las cuatro principales playas de la Provincia de Barahona, República Dominicana
Person localization using sensor information fusion
Nowadays the incredible grow of mobile devices market led
to the need for location-aware applications. However, sometimes person
location is di cult to obtain, since most of these devices only have a GPS
(Global Positioning System) chip to retrieve location. In order to sup-
press this limitation and to provide location everywhere (even where a
structured environment doesn't exist) a wearable inertial navigation sys-
tem is proposed, which is a convenient way to track people in situations
where other localization systems fail. The system combines pedestrian
dead reckoning with GPS, using widely available, low-cost and low-power
hardware components. The system innovation is the information fusion
and the use of probabilistic methods to learn persons gait behavior to
correct, in real-time, the drift errors given by the sensors.This work is part-funded by ERDF - European Regional Development Fund through
the COMPETE Programme (operational programme for competitiveness) and by
National Funds through the FCT Fundao para a Cincia e a Tecnologia (Portuguese
Foundation for Science and Technology) within project FCOMP-01-0124-FEDER-
028980 (PTDC/EEI-SII/1386/2012). Ricardo also acknowledge FCT for the support
of his work through the PhD grant (SFRH/DB/70248/2010)
Engenharia ambiental subterrânea e aplicações
549 p.Apresenta em sua primeira uma revisão sobre a crescente importância da engenharia ambiental e a situação atual da sua especialização no âmbito subterrâneo. A segunda parte aborda a metodologia para a identificação das fontes e impactes ambientais negativos, para a caracterização da inter-relação dos parâmetros ambientais e expressando-os em modelos matemáticos, para a identificação do nível de impacte ambiental baseado na medição ou predição, na procura de medidas de prevenção e correção, aplicando-as da melhores alternativas e ainda, para a sua monitorização e controlo. Também, trata importantes aspectos do custo da proteção ambiental subterrânea. A terceira parte promove a aplicação dos conhecimentos acima referidos a duas minas portuguesas e uma mina peruana, visando validar a sua eficácia e fiabilidade. A quarta parte aborda a aplicação desta metodologia a projetos novos e aos sistemas de gestão ambiental (EMS) e sistemas de gestão do ambiente, saúde e segurança (EHS). Finalmente, a quinta parte, apresenta as principais conclusões do livro realizado e sugestões para futuras investigações
Systematic evidence mapping to assess the sustainability of bioplastics derived from food waste: Do we know enough?
Data Availability Statement: Not applicable.Copyright © 2022 by the authors. The production of bioplastics from food loss and waste (FLW), termed FLW-derived bioplastics, is considered an attractive alternative to first-generation bioplastics. To our knowledge, a clear understanding of the sustainability performance of FLW-derived bioplastics from environmental, economic, technical, and social aspects is still lacking. This systematic evidence mapping aims to fill this gap by undertaking a reality check on the life cycle sustainability performance of FLW-derived bioplastics from a multidimensional perspective underpinned by systems thinking approach to assess their potential to revolutionise the plastics economy. Results revealed that FLW-derived bioplastic production is highly complex and uncertain. The low technological readiness of FLW valorisation processes and the under-researched logistics of FLW management on a regional scale currently withhold advancement in this field. Nonetheless, progress is looming, and ensuring that FLW-derived bioplastics production enables the transition toward a sustainable bioeconomy is critical. Innovation in both the food and plastics value chains is urgently needed to address their challenges and mitigate pollution. Yet, any steps forward need to be holistically calculated to yield sustainability benefits and prevent unintended consequences.This research received no external funding
Ocorrência de parasitos gastrointestinais em cães (Canis familiaris) em três municípios da Baixada Santista
O artigo não apresenta resumo
Dense stellar clump formation driven by strong quasar winds in the FIRE cosmological hydrodynamic simulations
We investigate the formation of dense stellar clumps in a suite of high-resolution cosmological zoom-in simulations of a massive, star-forming galaxy at z ∼ 2 under the presence of strong quasar winds. Our simulations include multiphase ISM physics from the Feedback In Realistic Environments (FIRE) project and a no v el implementation of hyper-refined accretion disc winds. We show that powerful quasar winds can have a global negative impact on galaxy growth while in the strongest cases triggering the formation of an off-centre clump with stellar mass M ∼ 10 7 M , effective radius R 1 / 2 Clump ∼ 20 pc , and surface density ∼10 4 M pc −2 . The clump progenitor gas cloud is originally not star -forming, b ut strong ram pressure gradients driven by the quasar winds (orders of magnitude stronger than experienced in the absence of winds) lead to rapid compression and subsequent conversion of gas into stars at densities much higher than the average density of star-forming gas. The AGN-triggered star-forming clump reaches SFR ∼ 50 M yr −1 and SFR ∼ 10 4 M yr −1 kpc −2 , converting most of the progenitor gas cloud into stars in ∼2 Myr, significantly faster than its initial free-fall time and with stellar feedback unable to stop star formation. In contrast, the same gas cloud in the absence of quasar winds forms stars over a much longer period of time ( ∼35 Myr), at lower densities, and losing spatial coherency. The presence of young, ultra-dense, gravitationally bound stellar clumps in recently quenched galaxies could thus indicate local positive feedback acting alongside the strong negative impact of powerful quasar winds, providing a plausible formation scenario for globular clusters
Dense stellar clump formation driven by strong quasar winds in the FIRE cosmological hydrodynamic simulations
We investigate the formation of dense stellar clumps in a suite of
high-resolution cosmological zoom-in simulations of a massive, star forming
galaxy at under the presence of strong quasar winds. Our simulations
include multi-phase ISM physics from the Feedback In Realistic Environments
(FIRE) project and a novel implementation of hyper-refined accretion disk
winds. We show that powerful quasar winds can have a global negative impact on
galaxy growth while in the strongest cases triggering the formation of an
off-center clump with stellar mass , effective radius ,
and surface density . The clump progenitor gas cloud is originally not star-forming, but
strong ram pressure gradients driven by the quasar winds (orders of magnitude
stronger than experienced in the absence of winds) lead to rapid compression
and subsequent conversion of gas into stars at densities much higher than the
average density of star-forming gas. The AGN-triggered star-forming clump
reaches and , converting
most of the progenitor gas cloud into stars in 2\,Myr, significantly
faster than its initial free-fall time and with stellar feedback unable to stop
star formation. In contrast, the same gas cloud in the absence of quasar winds
forms stars over a much longer period of time (35\,Myr), at lower
densities, and losing spatial coherency. The presence of young, ultra-dense,
gravitationally bound stellar clumps in recently quenched galaxies could thus
indicate local positive feedback acting alongside the strong negative impact of
powerful quasar winds, providing a plausible formation scenario for globular
clusters.Comment: 14 pages, 12 figure
Local positive feedback in the overall negative: the impact of quasar winds on star formation in the FIRE cosmological simulations
Negative feedback from accreting supermassive black holes is regarded as a
key ingredient in suppressing star formation and quenching massive galaxies.
However, several models and observations suggest that black hole feedback may
have a positive effect, triggering star formation by compressing interstellar
medium gas to higher densities. We investigate the dual role of black hole
feedback using cosmological hydrodynamic simulations from the Feedback In
Realistic Environments (FIRE) project, including a novel implementation of
hyper-refined accretion-disc winds. Focusing on a massive, star-forming galaxy
at (), we show that
strong quasar winds with kinetic power 10 erg/s acting for
20Myr drive the formation of a central gas cavity and can dramatically
reduce the star formation rate surface density across the galaxy disc. The
suppression of star formation is primarily driven by reducing the amount of gas
that can become star-forming, compared to directly evacuating the pre-existing
star-forming gas reservoir (preventive feedback dominates over ejective
feedback). Despite the global negative impact of quasar winds, we identify
several plausible signatures of local positive feedback, including: (1) spatial
anti-correlation of wind-dominated regions and star-forming clumps, (2) higher
local star formation efficiency in compressed gas near the edge of the cavity,
and (3) increased local contribution of outflowing material to star formation.
Stars forming under the presence of quasar winds tend to do so at larger radial
distances. Our results suggest that positive and negative AGN feedback can
coexist in galaxies, but local positive triggering of star formation plays a
minor role in global galaxy growth.Comment: 17 pages, 12 figure
The KELT Follow-Up Network And Transit False-Positive Catalog: Pre-Vetted False Positives For TESS
The Kilodegree Extremely Little Telescope (KELT) project has been conducting a photometric survey of transiting planets orbiting bright stars for over 10 years. The KELT images have a pixel scale of ~23\u27\u27 pixel⁻¹—very similar to that of NASA\u27s Transiting Exoplanet Survey Satellite (TESS)—as well as a large point-spread function, and the KELT reduction pipeline uses a weighted photometric aperture with radius 3\u27. At this angular scale, multiple stars are typically blended in the photometric apertures. In order to identify false positives and confirm transiting exoplanets, we have assembled a follow-up network (KELT-FUN) to conduct imaging with spatial resolution, cadence, and photometric precision higher than the KELT telescopes, as well as spectroscopic observations of the candidate host stars. The KELT-FUN team has followed-up over 1600 planet candidates since 2011, resulting in more than 20 planet discoveries. Excluding ~450 false alarms of non-astrophysical origin (i.e., instrumental noise or systematics), we present an all-sky catalog of the 1128 bright stars (6 \u3c V \u3c 13) that show transit-like features in the KELT light curves, but which were subsequently determined to be astrophysical false positives (FPs) after photometric and/or spectroscopic follow-up observations. The KELT-FUN team continues to pursue KELT and other planet candidates and will eventually follow up certain classes of TESS candidates. The KELT FP catalog will help minimize the duplication of follow-up observations by current and future transit surveys such as TESS
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