38 results on '"Simões, Nuno"'
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2. Laboratory assessment of the hygrothermal performance of an external vacuum-insulation composite system
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Gonçalves, Márcio, Simões, Nuno, Serra, Catarina, and Flores-Colen, Inês
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- 2022
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3. Application of smart readiness indicator for Mediterranean buildings in retrofitting actions
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Ramezani, Bahareh, Silva, Manuel. Gameiro da, and Simões, Nuno
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- 2021
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4. Influence of a period of wet weather on the heat transfer across a wall covered with uncoated medium density expanded cork
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Fino, Rosário, Tadeu, António, and Simões, Nuno
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- 2018
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5. Feeding the lined seahorse Hippocampus erectus with frozen amphipods
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Vargas-Abúndez, Jorge Arturo, Simões, Nuno, and Mascaró, Maite
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- 2018
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6. Heat transfer measurements of a linear thermal bridge in a wooden building corner
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Prata, Joana, Simões, Nuno, and Tadeu, António
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- 2018
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7. Benchmarks and sediment source(s) of the 1755 Lisbon tsunami deposit at Boca do Rio Estuary
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Font, Eric, Veiga-Pires, Cristina, Pozo, Manuel, Nave, Sílvia, Costas, Susana, Ruiz Muñoz, Francisco, Abad, Manuel, Simões, Nuno, Duarte, Sílvia, and Rodríguez-Vidal, Joaquín
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- 2013
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8. Pathogenicity and colonization of Litopenaeus vannamei larvae by luminescent vibrios
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Soto-Rodríguez, Sonia A., Simoes, Nuno, Roque, Ana, and Gómez Gil, Bruno
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- 2006
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9. Drainage and water storage capacity of insulation cork board applied as a layer on green roofs.
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Tadeu, António, Simões, Nuno, Almeida, Ricardo, and Manuel, Carlos
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WATER storage , *DRAINAGE , *GREEN roofs , *CORK , *HYDRAULICS , *WATER testing , *CURRICULUM - Abstract
Highlights • Evaluation of water drainage and storage capacity of insulation cork board (ICB). • Thickness and density of ICB affect drainage and storage performance. • Density of ICB has a greater effect on drainage capacity. • Redesigned ICB system outperformed the system built with the reference product. Abstract This paper evaluates experimentally the water drainage and water storage capacity of insulation cork board (ICB), a natural material, applied as one layer of a green roof system. The apparatus that was designed and built to support and water the test specimens is described. The study examines ICB samples of different thicknesses and densities. The results were compared with those provided by a polyolefin material widely used in these solutions. The full system was tested with and without the substrate typically used in green roof systems. It was found that both the thickness and density of the cork board affect its drainage and storage performance. However, the results indicate that a change in density has a greater effect on drainage capacity. It was found that when the tested specimens included a substrate layer, the peak water flow decreased and the water retention increased. During the course of the study it was also found necessary to redesign the geometry of the ICB to cope with extreme wetting conditions in a complete green roof system. This adjustment meant that when the lower density ICB was used as a drainage layer of a green roof system it outperformed the systems built with the reference product. [ABSTRACT FROM AUTHOR]
- Published
- 2019
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10. Uncoated medium density expanded cork boards for building façades and roofs: Mechanical, hygrothermal and durability characterization.
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Simões, Nuno, Fino, Rosário, and Tadeu, António
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ARCHITECTURE & energy conservation , *ELECTRIC insulators & insulation , *HYGROTHERMOELASTICITY , *MECHANICAL loads , *DURABILITY - Abstract
Highlights • Characterization of expanded cork used as an uncoated building solution. • Mechanical and hygrothermal properties of standard and medium density expanded cork. • Medium density expanded cork has a better mechanical performance. • Medium density expanded cork is resistant to long-term external exposure. • Medium density expanded cork is suitable as an uncoated external insulation solution. Abstract The use of more efficient and greener insulation products is a strategy that is being followed to achieve more sustainable energy efficient buildings. Given these concerns, expanded cork boards, which are 100% natural and recyclable, are being used more often as the only coating for building façades, without any additional protection. In this context, this work evaluates the performance of standard (90–110 kg/m3) and medium (140–160 kg/m3) density expanded cork boards to be applied as an uncoated solution for building façades and roofs. As the building envelope is exposed to external conditions (wind pressure, rain, temperature and moisture gradients, sunlight and mechanical loads), a wide range of laboratory tests were performed to evaluate their mechanical, hygrothermal and durability characteristics. It was found that the medium density cork board is more suitable for the uncoated external insulation of building façades and roofs, since it has a better mechanical performance, without compromising its hygrothermal behaviour. It was found that it is also resistant to long-term exposure to external conditions. [ABSTRACT FROM AUTHOR]
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- 2019
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11. Review of the experimental methods for evaluation of windows' solar heat gain coefficient: From standardized tests to new possibilities.
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Abolghasemi Moghaddam, Saman, Simões, Nuno, and Gameiro da Silva, Manuel
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SOLAR heating ,SOLAR technology ,STANDARDIZED tests ,EVALUATION methodology ,PHOTOVOLTAIC power systems - Abstract
One of the most important properties of a glazing system is the solar heat gain coefficient (SHGC, or g-value) which quantifies the passive solar thermal gains. There are several standardized numerical methods of determining a window's g-value. However, the methods do not consider the glazing systems in real boundary conditions, and usually are subjected to assumptions and empirical parameters regarding the thermal/optical behavior of the system, and the rate of ventilation of the gap between the glazing unit and the shading device which would result in under- or over-estimation of the results. For this reason, several experimental methods for investigating the g-value of windows have been developed to be used either alone or as a supplementary method for the validation purpose. This review aims to analyze the main experimental methods for assessing the g-value of windows that have been published as international standards or as scientific papers while taking into consideration the condition of experiment (laboratory or in-situ) and the part of the window which was tested (the glazing part or the entire window). The methods reviewed here include standardized numerical methods based on spectrophotometric measurements, solar calorimetric methods, non-calorimetric and in-situ methods. This review set out to give insights into the procedure, the necessary equipment units, the advantages and disadvantages, new possibilities, and the gaps associated with each method. At the end the authors proposed an approach for comparing the reviewed methods more precisely and confidently, and for investigating the reliability of in-situ methods. [ABSTRACT FROM AUTHOR]
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- 2023
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12. A comparison between cost optimality and return on investment for energy retrofit in buildings-A real options perspective.
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Tadeu, Sérgio Fernando, Alexandre, Rafael F., Tadeu, António J.B., Antunes, Carlos Henggeler, Simões, Nuno A.V., and Silva, Patrícia Pereira da
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RATE of return ,SUSTAINABLE buildings ,GENETIC algorithms ,ENERGY conservation in buildings ,DECISION making - Abstract
European Union (EU) regulations aim to ensure that the energy performance of buildings meets the cost-optimality criteria for energy efficiency measures. The methodological framework proposed in EU Delegated Regulation 244 is addressed to national authorities (not investors); the optimal cost level is calculated to develop regulations applicable at domestic level. Despite the complexity and the large number of possible combinations of economically viable efficiency measures, the real options for improving energy performance available to decision makers in building retrofit can be established. Our study considers a multi-objective optimization approach to identify the minimum global cost and primary energy needs of 154,000 combinations of energy efficiency measures. The proposed model is solved by the NSGA-II multi-objective evolutionary algorithm. As a result, the cost-optimal levels and a return on investment approach are compared for a set of suitable solutions for a reference building. Eighteen combinations of retrofit measures are selected and an analysis of the influence of real options on investments is proposed. We show that a sound methodological approach to determining the advantages of this type of investment should be offered so that Member States can provide valuable information and ensure that the minimum requirements are profitable to most investors. [ABSTRACT FROM AUTHOR]
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- 2016
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13. Experimental studies on the effect of food in early larvae of the cleaner shrimp Lysmata amboinensis (De Mann, 1888) (Decapoda: Caridea: Hippolytidae)
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Cunha, Luís, Mascaro, Maite, Chiapa, Xavier, Costa, Ana, and Simoes, Nuno
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- 2008
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14. Transient conduction and convection heat transfer across a multi-layer floor subjected to multiple heat sources.
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Simões, Nuno and Tadeu, António
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HEAT transfer ,FOURIER transforms ,ENERGY transfer ,FOURIER analysis - Abstract
Abstract: This paper analyses the transient heat transfer across multi-layer floors subjected to multiple heat sources. The formulation that is proposed to solve this problem uses analytical expressions handling both conduction and convection phenomena. The Green''s functions (analytical expressions) for the layered formation are established by imposing the continuity of temperatures and heat fluxes at the medium interfaces between the various layers. The heat field inside a layer is obtained by adding the contribution of the direct heat incident field, generated as in an unbounded medium, to the heat produced by a set of virtual surface heat sources, that take into account the presence of the interfaces. The technique used to deal with the unsteady state conditions consists of first computing the solution in the frequency domain and then applying (fast) inverse Fourier transforms into space-time. [Copyright &y& Elsevier]
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- 2006
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15. Heat conduction across double brick walls via BEM.
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Branco, Fernando, Tadeu, António, and Simões, Nuno
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HEAT conduction ,BOUNDARY element methods ,HYGROTHERMOELASTICITY - Abstract
The Boundary Element Method (BEM) is used to compare the steady-state heat and moisture diffusion behaviour across double brick walls provided by two different models: in the first one, the brick wall is assumed to be composed of a set of homogeneous layers bonded together, which is the model frequently used to predict internal condensation; in the second model, the geometrical modelling and hygrothermal properties of the individual bricks are taken into account.The BEM is implemented allowing the use of multi boundaries, which permits the full discretization of the brick cavities.Three different construction solutions are analysed. In the first, the double-brick wall is assumed not to be thermally insulated; in the second, the space between the two layers of bricks is filled with thermal insulation material; in the third solution, both the space between the brick layers and the holes of the inner brick layer are filled with thermal insulating material. [Copyright &y& Elsevier]
- Published
- 2004
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16. Steady-state moisture diffusion in curved walls, in the absence of condensate flow, via the BEM: a practical Civil Engineering approach (Glaser method).
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Tadeu, António, Simões, Nuno, and Branco, Fernando
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CONDENSATION ,HEAT transfer ,VAPOR pressure - Abstract
The influence of the curvature radius of curved walls on the condensation patterns across a single panel homogeneous wall is analysed under steady-state conditions. Condensation is defined according to the Glaser approach, which is a practical tool in building design, recommended by the DIN 4108 and prEN ISO 13788 standards. This methodology uses an iterative process, which requires the resolution of temperature equilibrium and several vapour pressure equilibrium problems. Each of these potential problems is solved using the Boundary Element Method (BEM). The iterative process is first implemented and validated by applying it to the definition of condensation patterns across a hollow cylinder, for which the solution is calculated analytically. The BEM is then applied to the curved wall models, identifying the zones where condensation occurs and quantifying the amount of liquid water generated. [Copyright &y& Elsevier]
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- 2003
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17. Can vacuum insulation panels be cost-effective when applied in building façades?
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Simões, Nuno, Gonçalves, Márcio, Serra, Catarina, and Resalati, Shahaboddin
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VACUUM insulation ,OFFICE buildings ,LIFE cycle costing ,ECONOMIC change ,THERMAL insulation ,INSULATING materials - Abstract
A key factor for achieving nearly-zero energy buildings is to reduce their energy demand using highly efficient thermal insulation materials, such as vacuum insulation panels (VIPs). Currently, the high investment cost of VIPs is hindering the technology penetrating the building market. However, their high thermal performance coupled with reduced thicknesses can lead to economic benefits associated with space savings, significantly changing the economic standing of VIPs. This study presents a comprehensive life cycle cost (LCC) analysis of the application of VIPs in external thermal insulation composite systems (ETICS) in office building façades performed from the landlord perspective. The proposed LCC methodology, based on the EU cost-optimal regulation, allows for comparing the cost-effectiveness of VIPs with conventional insulation materials, taking full account of the additional rental income due to space savings. Energy calculations are performed based on transient heat transfer. The study takes into account varying parameters, such as location, cost of materials, insulation thickness, and rental prices, among others. The results demonstrate that VIPs can be economically viable, in particular in cities where office full-leasing rental prices are high. The range of VIP and rental prices that make their use in buildings cost-effective are identified. For example, it is shown that for rental costs higher than 350 €/(m
2 .y) VIP can be cost-effective for a current market price of 3000 €/m3 , when local climate demands for thermal transmittance bellow 0.19 W/(m2 .K). This analysis is useful for VIP manufacturers, project owners and landlords that may be looking for competitive insulation products. • Global costs for a vacuum panel system are compared with conventional insulation. • A methodology for life cycle cost analysis, including rental costs, is used. • Energy balance is determined with transient calculations for a unit area of wall. • The influence of changing several technical and economic parameters is discussed. • VIPs can be found to be cost-effective for buildings in high rent locations. [ABSTRACT FROM AUTHOR]- Published
- 2021
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18. Three-dimensional fundamental solutions for transient heat transfer by conduction in an unbounded medium, half-space, slab and layered media
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Tadeu, António and Simões, Nuno
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GREEN'S functions , *HEAT transfer , *HEAT conduction , *TRANSIENTS (Dynamics) , *BESSEL functions - Abstract
Abstract: This paper presents analytical Green''s functions for the transient heat transfer phenomena by conduction, for an unbounded medium, half-space, slab and layered formation when subjected to a point heat source. The transient heat responses generated by a spherical heat source are computed as Bessel integrals, following the transformations proposed by Sommerfeld [Sommerfeld A. Mechanics of deformable bodies. New York: Academic Press; 1950; Ewing WM, Jardetzky WS, Press F. Elastic waves in layered media. New York: McGraw-Hill; 1957]. The integrals can be modelled as discrete summations, assuming a set of sources equally spaced along the vertical direction. The expressions presented here allow the heat field inside a layered formation to be computed without fully discretizing the interior domain or boundary interfaces. The final Green''s functions describe the conduction phenomenon throughout the domain, for a half-space and a slab. They can be expressed as the sum of the heat source and the surface terms. The surface terms need to satisfy the boundary conditions at the surfaces, which can be of two types: null normal fluxes or null temperatures. The Green''s functions for a layered formation are obtained by adding the heat source terms and a set of surface terms, generated within each solid layer and at each interface. These surface terms are defined so as to guarantee the required boundary conditions, which are: continuity of temperatures and normal heat fluxes between layers. This formulation is verified by comparing the frequency responses obtained from the proposed approach with those where a double-space Fourier transformation along the horizontal directions [Tadeu A, António J, Simões N. 2.5D Green''s functions in the frequency domain for heat conduction problems in unbounded, half-space, slab and layered media. CMES: Computer Model Eng Sci 2004;6(1):43–58] is used. In addition, time domain solutions were compared with the analytical solutions that are known for the case of an unbounded medium, a half-space and a slab. [Copyright &y& Elsevier]
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- 2006
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19. Fundamental solutions for transient heat transfer by conduction and convection in an unbounded, half-space, slab and layered media in the frequency domain
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Simões, Nuno and Tadeu, António
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GREEN'S functions , *HEAT equation , *FOURIER transforms , *HEAT convection , *TIME-domain analysis - Abstract
Abstract: Analytical Green''s functions in the frequency domain are presented for the three-dimensional diffusion equation in an unbounded, half-space, slab and layered media. These proposed expressions take into account the conduction and convection phenomena, assuming that the system is subjected to spatially sinusoidal harmonic heat line sources and do not require any type of discretization of the space domain. The application of time and spatial Fourier transforms along the two horizontal directions allows the solution of the three-dimensional time convection-diffusion equation for a heat point source to be obtained as a summation of one-dimensional responses. The problem is recast in the time domain by means of inverse Fourier transforms using complex frequencies in order to avoid aliasing phenomenon. Further, no restriction is placed on the source time dependence, since the static response is obtained by limiting the frequency to zero and the high frequency contribution to the response is small. The proposed functions have been verified against analytical time domain solutions, known for the case of an unbounded medium, and the Boundary Element Method solutions for the case of the half-space, slab and layered media. [Copyright &y& Elsevier]
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- 2005
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20. Definition of two-dimensional condensation via BEM, using the Glaser method approach.
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Simões, Nuno, Branco, Fernando, and Tadeu, António
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CONDENSATION , *BOUNDARY element methods - Abstract
This work describes an iterative technique for the definition of condensation across two-dimensional elements via the boundary element method (BEM). Initially, the BEM is used to calculate the steady-state conduction of heat and vapour diffusion, discretizing only the boundary materials'' discontinuities. Then, a small sub-domain is defined, where condensation develops; that is, where the vapour pressure exceeds the vapour saturation pressure. Using the Glaser approach, the vapour pressure is equalised to the vapour saturation pressure, and then the vapour equilibrium is redefined by means of the BEM solution. This process is repeated until all sub-domains where vapour pressure exceeds vapour saturation pressure are eliminated.The method is first implemented and validated by applying it to a simple one-dimensional hygrothermal problem, for which the solution is calculated analytically. The applicability of the proposed method is then illustrated by computing the two-dimensional condensation across a T shaped element, for different boundary conditions. [Copyright &y& Elsevier]
- Published
- 2002
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21. Integrated environmental, energy and cost life-cycle analysis of windows: Optimal selection of components.
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Saadatian, Shiva, Simões, Nuno, and Freire, Fausto
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COST analysis ,WINDOWS ,ENERGY consumption of buildings ,LIFE cycle costing ,ENVIRONMENTAL economics - Abstract
There is an increasing need for energy-efficient windows; however, these windows can have high embodied impacts and can be costly. This has not been thoroughly analyzed and the literature has mainly focused on the operational performance of windows. It is important to wisely select optimal windows that minimize energy consumption, costs, and environmental impacts throughout their life cycle, considering the influence of window orientation and climate data. This article presents an integrated cost and environmental life-cycle assessment (LCA) of window solutions, combining alternative glazing and framing options. Optimal window solutions were selected using a Pareto bi-objective optimization (costs vs. environmental impacts) for three different European climate regions, considering various window orientations. The influence of each window component (glazing and framing), as well as window properties (thermal transmittance and solar factor) on the overall environmental and cost life-cycle impacts was studied. Pareto optimal window solutions for warm climates highlight low solar factor windows, while for cold climates they highlight low thermal transmittance value. The glazing is the component with the greatest influence on the total environmental impacts (mainly operational). The impacts depend to a very great extent on the thermal transmittance values and solar factors. The life-cycle cost analysis shows that the initial investment in the windows has a high impact on the overall cost, even when a lifespan of 30 years is considered. This article provides insights into and recommendations for the design of windows by addressing different climatic conditions and window orientations. • Trade-offs between environmental impacts and costs of windows are presented. • The influence of climate and orientation on window performance is investigated. • West-facing windows have higher impacts due to the larger energy needs. • In warm climates, low solar factor contributes significantly to reduce impacts. • Window thermal transmittance is key to reduce impacts in cold climates. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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22. Comparative life cycle assessment of different vacuum insulation panel core materials using a cradle to gate approach.
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Resalati, Shahaboddin, Okoroafor, Tobechi, Henshall, Paul, Simões, Nuno, Gonçalves, Márcio, and Alam, Mahmood
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CORE materials ,VACUUM insulation ,ENVIRONMENTAL impact analysis ,INSULATING materials ,THERMAL conductivity - Abstract
The global market trend for Vacuum Insulation Panels (VIPs) is projecting a significant increase in their uptake in the construction sector. This is mainly due to the uniquely high-performance properties of the ultra-thin insulation materials. This uptake, however, can potentially be hindered by the VIPs' higher cost and environmental impacts when compared with conventional insulation materials. This paper, for the first time, presents a detailed evaluation of the environmental impact of the most common type of VIPs currently used in different applications with a focus on alternating the core material as the main contributing component to their footprint. Pyrogenic silica, glass fibre, expanded polystyrene, aerogel and a silica/sawdust hybrid core were analysed from cradle to gate. The study, on a comparative basis, demonstrates the sensitivity of the various environmental impact categories to the internal vacuum pressure and the subsequent thermal conductivity values. The results show a lower environmental impact for glass fibre and low density expanded polystyrene compared to the other alternatives. Pyrogenic silica, the most common core material, had the highest environmental impact out of the core materials considered. The higher environmental impacts of pyrogenic silica suggest that measures such as the recycling of the core material alongside the deployment of eco-friendlier manufacturing techniques should be considered if the material is to compete environmentally with the other alternative materials. Image 1 • Environmental impact of different VIP core materials was compared for the first time. • Cradle to gate approach has been adopted for the analyses in accordance with EN15804. • Sensitivity analyses conducted for internal vacuum pressure and core material EPDs. • Pyrogenic silica had the highest environmental impact of the core materials studied. • Glass fibre had the lowest environmental impact for vacuum pressures lower than 10Pa. [ABSTRACT FROM AUTHOR]
- Published
- 2021
- Full Text
- View/download PDF
23. Comparison between cork-based and conventional green roof solutions.
- Author
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Simões, Nuno, Almeida, Ricardo, Tadeu, António, Brett, Michael, and Almeida, João
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GREEN roofs ,THERMAL resistance ,WATER storage ,GEOTHERMAL resources ,HEAT pipes ,THERMAL insulation ,BUILDING operation management - Abstract
Green roofs are increasingly being used to improve the energy balance and stormwater management of buildings. This work examines the thermal behaviour, water drainage and vegetation growth of two green roof systems: a conventional system containing extruded polystyrene and polyethylene, and an alternative cork-based system. In the new system, an eco-friendly expanded cork layer is used to provide thermal resistance and water storage capacity in a more sustainable way, as cork is a natural material. This material can also be used as an uncoated finishing layer for architectural purposes. The main goal of this work was to see if the new system is reliable in real environmental conditions and to compare its behaviour to that of the conventional system for a full year. This work presents the results of a fully functioning prototype built in Portugal with a technical substrate 10 cm thick and planted with a variety of vegetation. The reference and proposed systems were installed side by side and monitored under spring, summer, autumn and winter conditions. The thermal insulation and the water drainage and storage capacity provided by the cork-based green roof were found to be similar to those of the reference solution, with the expanded cork layer showing a more marked temperature delay and a more effective management of rainfall events under dry conditions. Additionally, it was found that the growth and health of plants in the cork-based green roof were comparable to those of the reference solution, indicating the good performance of the cork system. • An innovative cork-based green roof system was compared with a conventional solution. • Thermal, drainage and vegetation behaviour were assessed under real conditions. • More pronounced temperature delays were exhibited by the cork-based system. • The cork-based system was more effective at managing the drainage of the first rainfall event. • Vegetation development was similar for the two green roofs compared here. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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- View/download PDF
24. A review of the challenges posed by the use of vacuum panels in external insulation finishing systems.
- Author
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Gonçalves, Márcio, Simões, Nuno, Serra, Catarina, and Flores-Colen, Inês
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VACUUM insulation , *INSULATING materials , *THERMAL insulation , *BUILDING performance , *VACUUM technology , *SERVICE life , *THERMAL conductivity - Abstract
• The use of vacuum technology can improve the energy performance of buildings. • VIP products available for external insulation and case studies are discussed. • Design and installation, durability and economic viability are the main challenges. • High cost and service life are key-factors for the wide-scale use of vacuum panels. • Guidelines for performing an adequate evaluation of this solution is proposed. The worldwide demand for energy efficiency calls for improvements in the thermal performance of buildings. As a result, there is a growing interest in the use of high-performance insulation materials such as vacuum insulation panels (VIPs). Due to their low thermal conductivity, high insulation levels can be achieved with thinner walls than is possible with conventional thermal insulation materials. An interesting solution might be to combine a vacuum insulation panel with the well-known external thermal insulation composite system (ETICS). However, in terms of practical application and long-term performance, this solution needs to be looked into further. This paper aims to review the challenges posed when using VIPs in the external insulation of buildings. First, the main advantages and anomalies of ETICS are identified, after which the available VIPs solutions intended for external insulation are explored. Some case studies are presented and the main conclusions that may be drawn from these are highlighted. The difficulties of incorporating VIP products into ETICS are addressed. These include adapting/introducing covering layers to allow flatness and facilitate the handling of the products, defining and assessing a suitable fixation system, and ensuring the connection between construction elements. The main concerns regarding the ETICS with a VIPs solution are also discussed, such as edge thermal bridging, service life performance and installation, and the economic viability of the solution. Finally, we propose guidelines for performing a good evaluation of ETICS solutions that use VIPs. [ABSTRACT FROM AUTHOR]
- Published
- 2020
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- View/download PDF
25. Spatial assessment of the vulnerability of benthic communities to multiple stressors in the Yucatan Continental Shelf, Gulf of Mexico.
- Author
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Ocaña, Frank A., Pech, Daniel, Simões, Nuno, and Hernández-Ávila, Iván
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BENTHIC animals ,ECOLOGICAL assessment ,CONTINENTAL shelf ,BENTHIC ecology ,OCEAN acidification ,MARITIME shipping - Abstract
Here, we show a spatially explicit assessment of the vulnerability of benthic communities from the Yucatan Continental Shelf (YCS) to multiple pressures: fishing activities, shipping traffic, storms and hurricanes, and marine acidification. The vulnerability index was obtained by combining benthic biological traits with exposure and sensitivity and recovery capacity; this was then represented in a spatially explicit model. Moreover, we estimated a cumulative vulnerability index using three different scenarios that were based on 1) equal weight for each vulnerability layer to each stressor, 2) results of expert consultation and 3) a linear reduction in the weight of the pressures. By comparing scenarios, the synergistic and antagonistic effects of the multiple stressors were determined. The main results showed that, independent of the considered scenario, approximately 90% of the YCS presented moderate to high vulnerability to cumulative pressures, while areas with high recovery and high potential impact on a particular stressor showed low or moderate vulnerability to the pressures. Meanwhile, areas classified as having medium impact levels and low recovery capacities of benthic fauna showed moderate to high vulnerability to the same threats. Our findings also showed that ship traffic and marine acidification were the threats that contributed to the greatest vulnerability. The paired comparison of scenarios allows for the identification of areas with higher probabilities of synergistic effects. No antagonistic effects were detected. Overall, our results constitute the first effort to understand the ecological status of the benthic communities of the YCS and their potential vulnerability to the multiple pressures they face. • Vulnerability assessment to multiple pressures identify areas with high potential impact. • Marine traffic and ocean acidification are the main threats for the benthos. • The inclusion of benthic recovery traits improves the vulnerability assessment. • Synergistic and antagonistic impacts can be identified using pressures weighting scenarios. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
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26. Thermal behaviour of a green roof containing insulation cork board. An experimental characterization using a bioclimatic chamber.
- Author
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Almeida, Ricardo, Simões, Nuno, Tadeu, António, Palha, Paulo, and Almeida, João
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GREEN roofs ,THERMAL insulation ,CORK ,WATER storage ,CONCRETE slabs ,HEAT flux - Abstract
Green roof technology is increasingly being used to improve the energy and environmental performance of buildings. However, the description of the thermal behaviour of green roofs is very complex since it depends on several variables and relies on intricate phenomena. In this work the authors characterize a green roof system that replaces the conventional drainage and water storage polyethylene membranes with insulation cork boards (ICB). To enable the experimental characterization of this system, a double walk-in bioclimatic chamber was designed and built to recreate indoor and outdoor environmental conditions. Winter and summer environments with steady and unsteady conditions in both dry and wet states were simulated. Thermocouples and heat flux sensors were used to collect data over time from the different layers of the green roof prototypes. Measurements were first performed on a concrete slab insulated with ICB to assess the contribution of the latter to the thermal performance of the system. The effect on the heat transfer was further evaluated for systems of increasing complexity, containing first a substrate layer and then vegetation. It was noted that the substrate and vegetation layers improved the thermal insulation, and reduced heat fluxes and the thermal amplitude within the system. The vegetation layer was found to be of key importance to the overall performance of the green roof. It was also found that ICB and the substrate layers lose part of their insulation capacity when the system was wetted, although it was fully restored in the ICB layer within a few hours. • Green roof system using insulation cork boards (ICB) in the water storage layer. • Use of bioclimatic chambers that recreate environmental conditions. • Winter and summer environment conditions in both dry and wet states assessed. • ICB provides high insulation; substrate and vegetation both improve thermal delay. • After wetting, the ICB layer recovers its thermal insulation performance faster. [ABSTRACT FROM AUTHOR]
- Published
- 2019
- Full Text
- View/download PDF
27. Optimal location and sizing of storage units in a drainage system.
- Author
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Cunha, Maria C., Zeferino, João A., Simões, Nuno E., and Saldarriaga, Juan G.
- Subjects
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URBAN runoff , *CLIMATE change , *URBAN watersheds , *URBANIZATION , *HYDRAULICS , *MATHEMATICAL optimization - Abstract
Adapting urban stormwater drainage systems is essential to handling increased urbanization and climate change. Within an urban area, storage units are an efficient solution to reduce peak runoff, but their implementation involves complex decisions. This paper presents a novel optimization model for defining, in existing sewer drainage systems, the number of storage units, their location, size and the orifice dimensions. The orifice is used to reduce storage unit outflow regulating downstream flows. These components allow an integrated flow control and flooding reduction throughout the network. The desired solution should offer the lowest cost and try to avoid any major flooding impact. The model includes hydraulic, flood and capacity constraints and it is solved through a simulated annealing algorithm that calls upon a dynamic rainfall-runoff simulator for complete evaluation of each solution. The performance of the optimization model is assessed through a case study inspired by a real urban sewer network. [ABSTRACT FROM AUTHOR]
- Published
- 2016
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28. Dynamic simulation of three-dimensional heat conduction through cylindrical inclusions using a BEM model formulated in the frequency domain.
- Author
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Tadeu, António, Prata, Joana, and Simões, Nuno
- Subjects
- *
HEAT conduction , *BOUNDARY element methods , *FREQUENCY-domain analysis , *SIMULATION methods & models , *SURFACE temperature , *THERMOGRAPHY - Abstract
The analysis of surface temperatures in constructive elements using infrared thermography can be a useful tool for the in situ identification of constructive details and materials and for the evaluation of their thermal behaviour. It is therefore very important to be able to predict the effect of the materials’ thermophysical properties on heat diffusion. We present a numerical simulation model for the study of three-dimensional heat diffusion through cylindrical inclusions. This model is based on the boundary elements method (BEM), formulated in the frequency domain, and it was verified against two-dimensional analytical solutions that are known for cylindrical geometries. The proposed model was used to simulate heat conduction through a concrete column with a cylindrical inclusion embedded within it, subjected to a three-dimensional external heat point source. The effect of the inclusion properties and inclination on the temperature distribution inside the column and on its outer surface was analysed. The different heat wave phases of the physical models were compared. [ABSTRACT FROM AUTHOR]
- Published
- 2015
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29. Experimental validation of the Betti's Analytical Method for Double Glass Units.
- Author
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Galuppi, Laura, Zacchei, Enrico, Esteves, Miguel, Ferrão, João, and Simões, Nuno
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- *
GLASS construction , *STRUCTURAL plates , *GLASS , *HIGH temperatures , *MODEL validation - Abstract
The structural response of Insulating Glass Units (IGUs), formed of glass plates sealed by perimeter metal spacers entrapping a gas, is strongly influenced by the complex interaction between the glass plates and the gas, as well as by the structural coupling of the plates through the spacers. The former effect, called "load sharing", depends on the flexural stiffness of the plates and the pressure variation of the compressible gas due to applied actions. The more accurate and direct model to evaluate the load sharing is the recently proposed Betti's Analytical Method (BAM) (soon included in the new Eurocode on structural glass), which allows to evaluate the IGUs response under the most various support conditions and external loads. In this paper, the BAM model is revisited, and the result obtained by means of conjugate BAM-numerical analyses are carefully validated by means of comparison with the results of experimental tests. In particular, the results of an extensive experimental campaign, performed on Double GUs (DGUs) subjected to line-distributed and concentrated loads, both at the environmental and at high temperature, are presented. To properly account for the influence of geometric parameters on the DGU response, elements with various aspect ratio, glass thickness and cavity thickness have been considered. • The validation of BAM model for DGUs was made. • Complete analytical/numerical/experimental analyses for DGUs were carried out. • Structural effects of variations of gas temperature were considered. • "Load sharing" mechanism under linear/concentrated loads was studied. • Results were presented in terms of temperature/load–deflection responses. [ABSTRACT FROM AUTHOR]
- Published
- 2024
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30. Strategies to enhance the resistance of ETICS finishing coats to microbiological growth: A systematic study based on small- and large-scale laboratory tests.
- Author
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Azevedo, Ana, Almeida, João, Gonçalves, Márcio, Simões, Nuno, Castro, Nuno, Santos, Ana, and Tadeu, António
- Subjects
- *
ACRYLIC coatings , *FUNGAL colonies , *ALGAL growth , *THERMAL insulation , *SURFACE coatings , *FUNGAL growth - Abstract
• Enhanced resistance of ETICS finishing coats to microbiological colonization. • Improvement strategies based on thermal, hydrophobic and hydrophilic approaches. • Systematic study based on small- and large-scale laboratory tests. • Silicate-based formulations exhibit superior resistance to fungi and algae. • Glass microspheres and siloxane layers are insufficient to avoid bio-susceptibility. External thermal insulation composite systems (ETICS) are, in general, more likely to suffer from colonisation by fungi and algae than conventional walls, regardless of the nature of the biocide technology used. This results from the greater propensity of finishing coats applied on ETICS to develop surface condensation and, consequently, favourable conditions for microbiological growth. Most commonly, aesthetic degradation is the only implication. However, some severe cases can cause coating deterioration and loss of adhesion. In this work aiming to study resistance of ETICS finishing coats to fungi and algae growth, different improvement strategies based on thermal, hydrophobic, and hydrophilic approaches were exploited. In total, five different acrylic- and silicate-based formulations (without biocide) were prepared to screen the risk of condensation and biological resistance in separate small-scale laboratory tests. Based on the results obtained, selected finishing coats were applied on a large-scale ETICS wall and tested in a bioclimatic chamber capable of simulating conditions conducive to the early development of biological colonisation. The concomitant influence of biocides was also addressed at this stage. The results showed that a simple silicate-based formulation performs better than other tentative formulations tested, exhibiting a higher resistance to fungi and algae. They also suggested that incorporating glass microspheres or adding an external siloxane layer is not on its own effective in enhancing the resistance to the biological growth of acrylic- and silicate-based formulations. [ABSTRACT FROM AUTHOR]
- Published
- 2023
- Full Text
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31. Study of transient heat conduction in 2.5D domains using the boundary element method
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Godinho, Luís, Tadeu, António, and Simões, Nuno
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- *
HEAT conduction , *THERMAL diffusivity , *FOURIER transforms , *BOUNDARY element methods , *NUMERICAL analysis - Abstract
This paper presents the solution for transient heat conduction around a cylindrical irregular inclusion of infinite length, inserted in a homogeneous elastic medium and subjected to heat point sources placed at some point in the host medium. The solution is computed in the frequency domain for a wide range of frequencies and axial wavenumbers, and time series are then obtained by means of (fast) inverse Fourier transforms into space–time.The method and the expressions presented are implemented and validated by applying them to a cylindrical circular inclusion placed in an infinite homogeneous medium and subjected to a point heat source, for which the solution is calculated in closed form.The boundary elements method is then used to evaluate the temperature field generated by a point source in the presence of a cylindrical inclusion, with a non-circular cross-section, inserted in an unbounded homogeneous medium. Simulation analyses using this model are then performed to study the transient heat conduction in the vicinity of these inclusions. [Copyright &y& Elsevier]
- Published
- 2004
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32. Auto-responsive technologies for thermal renovation of opaque facades.
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Andrade Santos, Rita, Flores-Colen, Inês, Simões, Nuno, and Silvestre, José D.
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- *
FACADES , *BUILDING repair , *TECHNOLOGY assessment , *CLIMATE change , *RESEARCH & development - Abstract
Auto-responsive technologies (ARTs) operate in an intrinsic mode undergoing reversible changes in one or more of their properties in direct response to external stimuli variations. The aim of this paper is to identify their potential use for the thermal renovation of opaque facades of buildings in order to reach climate adaptivity. Adaptive facade concept offers a huge potential for thermal renovation, by improving occupants' comfort, promoting sector decarbonization, and being an opportunity for adapting facades to climate change. A literature review permitted the systematization of thermal renovation adaptive strategies (TRAS) in which ARTs can be useful. The facade reversible changes (outputs) required for each strategy were identified, as well as the possible adaptation mechanisms to obtain them. The technologies responding within the recognized adaptation mechanisms were described and compared, their readiness level identified and their role within the TRAS was assigned. An approach to assess the suitability of each ART regarding TRAS for existing facades was conceived. It uses the criteria of aesthetic change, additional space and demolition needs, localization and area of intervention. The role of each ART within each TRAS, here systematized, will support the definition of the ART's operational range for each application and climate, and will promote the research and development of these technologies for thermal renovation of buildings' facades. • Auto-responsive technologies role in thermal adaptive strategies for opaque facades • An open classification scheme for the operation of auto-responsive technologies • Suitability assessment of auto-responsive technologies for existing facades Image, graphical abstract [ABSTRACT FROM AUTHOR]
- Published
- 2020
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33. 3D chemoecology and chemotaxonomy of corals using fatty acid biomarkers: Latitude, longitude and depth.
- Author
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Figueiredo, Cátia, Baptista, Miguel, Rosa, Inês C., Lopes, Ana Rita, Dionísio, Gisela, Rocha, Rui J.M., Cruz, Igor C.S., Kikuchi, Ruy K.P., Simões, Nuno, Leal, Miguel Costa, Tojeira, Inês, Bandarra, Narcisa, Calado, Ricardo, and Rosa, Rui
- Subjects
- *
CHEMICAL ecology , *BIOCHEMISTRY , *PHYSIOLOGICAL effects of fatty acids , *CHEMOTAXONOMY , *OCTOCORALLIA - Abstract
With the objective of uncovering differences in the fatty acid (FA) composition of hexa- and octocorals from different climatic zones (equatorial, subtropical and tropical) and distinct habitats (e.g. rock and coral reefs; intertidal to deep-sea environments), the FA composition of 36 hexa- and octocoral species (132 specimens) was analysed (including the first characterization of organisms from the order Zoantharia and deep-sea gorgonians). PCA was applied in a FA matrix of the ten major PUFAs to detect differences among coral groups. Fatty acid profile analysis confirmed that C24 polyunsaturated FAs are suitable chemotaxonomic biomarkers to separate hexa- and octocorals. The polyunsaturated FA 22:6 n -3 was identified as a useful biomarker to distinguish between zoantharians and scleractinians. Also, we discuss the role of food availability (type of phytoplankton assemblage) in relation to autotrophic carbon significance and in the establishment of FA profiles of octocorals from the West and East coasts of the Atlantic Ocean. Furthermore, we show that the occurrence of high levels of primary productivity hinder the use of FA profiles to distinguish between zooxanthellate and azooxanthellate octocorals. Finally, we present and discuss the particular traits of the FA profile of deep-sea gorgonians while comparing it with that of shallow species. [ABSTRACT FROM AUTHOR]
- Published
- 2017
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34. Environmental and cost life-cycle approach to support selection of windows in early stages of building design.
- Author
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Saadatian, Shiva, Rodrigues, Carla, Freire, Fausto, and Simões, Nuno
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- *
ENVIRONMENTAL economics , *WINDOWS , *BUILDING performance , *PRODUCT life cycle assessment , *FUTURES market , *SOLAR power plants , *MEDICAL triage - Abstract
The selection of windows with the lowest life-cycle environmental impacts in an early-design stage is important to minimize impacts of buildings. Hence, an environmental and cost streamlined life-cycle assessment (LCA) approach, incorporating probabilistic triage, has been developed to support early-decision making for selection of window materials and components. This approach permits also to reduce the uncertainty in the estimated results by means of sequentially specifying attributes based on the attribute ranking. For demonstration purposes, a large number of window alternatives has been assessed for a reference office room. This approach proved to be effective in providing robust results to support the selection of windows by specifying very few window-related attributes (less than 8). The attribute ranking results show that the most influential attributes in terms of cost and environmental LCA are window-to-wall ratio and orientation, respectively. Future market window solutions with a wide range of alternative materials and components, impacting thermal transmittance and solar factor values, can be assessed using this approach to find optimal cost and environmental performance of buildings. • A large number of window alternatives assessed by a streamlined LCA approach. • Sequentially specified attributes analysis based on attribute ranking. • Robust early-stage decisions based on few specified attributes. • The most influential attributes are window-to-wall ratio and orientation. • Streamlined LCA approach to select future windows for a wide range of parameters. [ABSTRACT FROM AUTHOR]
- Published
- 2022
- Full Text
- View/download PDF
35. Host selection by the cleaner shrimp Ancylomenes pedersoni: Do anemone host species, prior experience or the presence of conspecific shrimp matter?
- Author
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Mascaró, Maite, Rodríguez-Pestaña, Lizbeth, Chiappa-Carrara, Xavier, and Simões, Nuno
- Subjects
- *
SHRIMPS , *SEA anemones , *FISH populations , *CONTINGENCY tables , *DECISION making , *MAXIMUM likelihood statistics , *ACCLIMATIZATION , *ANEMONES - Abstract
Abstract: In the symbiotic association that exists between cleaner shrimp Ancylomenes pedersoni (=Periclimenes pedersoni) and host sea anemones, specificity varies among populations, and shrimp are believed to search among different individual hosts for favourable positions from which to attract client fish. Four laboratory-based experiments were conducted to test host selection of A. pedersoni between the following: i) Bartholomea annulata (corkscrew anemone) and Condylactis gigantea (condy anemone), ii) B. annulata, with or without a conspecific resident, iii) a previously known or unknown B. annulata, and iv) a previously known or unknown C. gigantea. Preference (active selection) was distinguished from mere passive association by comparing shrimp acclimation to anemones offered in choice and no-choice (control) situations. The results were analysed using asymmetrical χ 2 contingency tables (in each experiment, n=60) where expected frequencies were obtained with maximum likelihood estimators. Shrimp acclimated more frequently to B. annulata than to C. gigantea, but they acclimated similarly to anemones with or without another resident and to those B. annulata and C. gigantea anemones that were familiar rather than unfamiliar. However, none of the χ 2 values were statistically significant (χ 2 df=1 =0.48, 0.19, 0.42, 0.42; overall p >0.45), suggesting that preference may not be responsible for the association between adult A. pedersoni and its host anemones observed in the field. Differences in the frequency of association may be due to factors other than the active decisions made by shrimp when presented with more than one alternative host. [Copyright &y& Elsevier]
- Published
- 2012
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36. Daily grass reference evapotranspiration with Meteosat Second Generation shortwave radiation and reference ET products.
- Author
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Paredes, Paula, Trigo, Isabel, de Bruin, Henk, Simões, Nuno, and Pereira, Luis S.
- Subjects
- *
LONG-range weather forecasting , *STANDARD deviations , *METEOROLOGICAL stations , *SOLAR radiation , *MARINE west coast climate , *EVAPOTRANSPIRATION - Abstract
This study assesses the accuracy of estimating daily grass reference evapotranspiration (PM-ET o) using daily shortwave radiation (R s) and reference evapotranspiration (ET REF) products provided by the Meteosat Second Generation (MSG) geostationary satellite delivered by the Satellite Applications Facility on Land Surface Analysis (LSA-SAF) framework. The accuracy of using reanalysis ERA5 shortwave radiation data (R s ERA5) provided by the European Center for Medium-Range Weather Forecasts (ECMWF) is also evaluated. The assessments were performed using observed weather variables at 37 weather stations distributed across continental Portugal, where climate conditions range from semi-arid to humid, and 12 weather stations located in Azores islands, characterized by humid, windy and often cloudy conditions. This study's use of data from a variety of climate conditions contributed to a unique and innovative assessment of the usability of LSA-SAF and ERA5 products for ET o estimation. The first assessment focused on comparing LSA-SAF estimates of R s (R s LSA-SAF) against ground stations (R s ground). The results showed a good matching between the two R s data sets for continental Portugal but a tendency for R s LSA-SAF to under-estimate R s ground in the cloudy islands of Azores. ET o values computed using R s LSA-SAF data and observed temperature, humidity and wind speed (ET o LSA-SAF) were then compared with PM-ET o estimates with ground-based data, which were used as benchmark; input data of temperature and humidity needed for PM-ET o were quality checked for surface aridity effects. It was observed that ET o LSA-SAF is strongly correlated with PM-ET o (R2 > 0.97) for most locations in continental Portugal, with regression coefficient of a linear regression forced to the origin ranging between 0.95 and 1.05, mean root mean square error (RMSE) of 0.13 mm d−1, and Nash and Sutcliff efficiency of modeling (EF) above 0.95. For most Azores locations, ET o LSA-SAF over-estimated PM-ET o. This is likely a consequence of the high spatio-temporal heterogeneity of weather conditions that occur in these oceanic islands together with the different footprints of satellite (averaged over the pixel) and station observations. Reanalysis ERA5 shortwave radiation data presented similar behavior to the LSA-SAF products, however with slightly lower accuracy. The daily LSA-SAF ET REF product (ET REF LSA-SAF) was assessed and results have shown a good accuracy of this product, with acceptable RMSE and high EF values, for continental Portugal but a low accuracy for the Azores islands. A simplified bias correction approach was shown to improve both ET o derived from the LSA-SAF products, namely for Azores stations, which seem to be representative of smaller areas. The use of the FAO-PM temperature approach (PMT) was also assessed using the R s LSA-SAF and R s ERA5 data, which showed a superiority of the LSA-SAF product for ET o estimations (ET o PMT LSA-SAF). No significant differences (p < 0.05) were observed in terms of the median value of the RMSE when adopting ET o PMT and ET REF LSA-SAF. Differently, results showed that using the R s LSA-SAF in the PMT approach (ET o PMT LSA-SAF) produces significantly better RMSE results than ET o PMT and ET REF LSA-SAF. Overall, the performed assessment allows concluding that the use of R s LSA-SAF, and to a lesser extent the use of the R s ERA5 , highly improves the accuracy of computation of ET o when R s observations are not available, including when only temperature data are accessible. The use of the ET REF LSA-SAF product is a good alternative when observed weather data are not available. • Satellite LSA-SAF solar radiation (R s) closely fits ground R s in continental sites leading to highly accurate PM-ET o estimates. • Humid, windy and cloudy climate of oceanic islands lead to pixel heterogeneities and over-estimation trends for R s and ET o • ERA5 reanalysis R s show a behavior similar to LSA-SAF product but with slightly lower accuracy. • Reference ET product of LSA-SAF over continental sites are accurate but highly uncertain for the oceanic islands. • LSA-SAF and ERA5 R s data led to improved accuracy when used to compute PM-ET o relative to computing with temperature only. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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37. Influence of bottom environment conditions and hydrographic variability on spatiotemporal trends of macrofaunal amphipods on the Yucatan continental shelf.
- Author
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Paz-Ríos, Carlos E., Pech, Daniel, Mariño-Tapia, Ismael, and Simões, Nuno
- Subjects
- *
CONTINENTAL shelf , *AMPHIPODA , *SPECIES diversity , *UPWELLING (Oceanography) , *COMMUNITY organization , *BIOTIC communities , *MESOSCALE eddies - Abstract
Amphipod species collected during three oceanographic campaigns (2010–2012) were analyzed to describe their spatiotemporal community distribution trends and their relationships with bottom water and sediment variables. The results show that the species richness (117 spp.) did not reach its maximum value according to the species accumulation curve (up to 187 spp.). Multivariate analyses and constrained ordinations techniques detected three main amphipod assemblages along the longitudinal gradient (i.e., Western Caribbean, Mid-Yucatan, and West-Yucatan) and during two temporal hydrographic scenarios (i.e., upwelling in 2010–2011 and non-upwelling in 2012). In 2010–2011, low values in species richness and abundance from the Western Caribbean and eastern Mid-Yucatan assemblages were associated with relatively low bottom-water temperatures from the upwelling systems. In 2012, the absence of upwelling and the occurrence of a warm-core anticyclonic eddy seemed to cause an increase in species richness and abundance in the three assemblages. The hydrographic variability and sediment characteristics are suggested as the major environmental drivers that shapes the soft-bottom amphipod community structure and diversity in the Yucatan continental shelf. • Three species assemblages were identified along the longitudinal gradient. • Depth gradient influence the species richness, abundance, and species composition. • The upwelling systems influence the temporal variability of the species assemblages. • Hydrographic and sedimentary variability induces major changes in the distribution and diversity of amphipods. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
38. Cold temperature tolerance of the alien Indo-Pacific damselfish Neopomacentrus cyanomos from the Southern Gulf of Mexico.
- Author
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Tremblay, Nelly, Guerra-Castro, Edlin J., Díaz, Fernando, Rodríguez-Fuentes, Gabriela, Simões, Nuno, Robertson, D. Ross, and Rosas, Carlos
- Subjects
- *
COLD (Temperature) , *OCEAN temperature , *LOW temperatures , *TEMPERATURE effect , *BAYS - Abstract
The abundance of the alien, Indo-Pacific damselfish Neopomacentrus cyanomos on an oil-loading platform in the southwest Gulf of Mexico indicates that widely distributed platforms could facilitate the expansion of its geographic range across the western and northern fringes of the Gulf. From there it likely will spread to other areas of the Greater Caribbean. The lionfish example demonstrates that it eventually happens, and can do so rapidly. Reduced temperature effects on the physiology of this species were examined to better predict its survivability in the northern Gulf during winter, when sea surface temperatures fall as low as 15 °C along the coast. Overall, our results show that when the degree of experimental temperature decline was large and rapid, no compensation occurred and the stress response observed mostly reflected cellular processes that minimized damage. Integrated biomarker response values were significantly different between fish rapidly exposed to colder vs. warmer temperatures (declines of −4 °C each day, from 26 to 14 °C), reflected in higher values of blood metabolites and routine metabolic rates observed in fish exposed to 14 and 18 °C respectively, and lower activity of all enzymes, lower protein carbonylation, and higher oxidative damage to lipids in fish exposed to 14 °C. While the physiological proxies responded to minimize damage during the rapid-decrease experiment, the same proxies reflected the consequences of compensation when fish were thermally challenged after a 45 days acclimation at 18 °C. In this case, lower values of blood metabolites and high antioxidant levels and indicators of damages underpinned its pejus lower range. Based on the results of the present work, it seems clear that low winter SSTs in the northern Gulf will slow down the colonization of the inshore area of N. cyanomos. We suggest that the use of physiological cellular stress markers on specimens acquired at the beginning of an invasion should be implemented in new standardized experimental protocols, including both rapid increases/decreases of temperature and post-acclimation temperature challenges, to assess the invasiveness potential of aquatic species such as this. Unlabelled Image • Species native's data are often used to predict its invasion potential as alien. • Reduced temperature on alien Neopomacentrus cyanomos' physiology was examined. • Higher routine metabolic rates were noted at 18 °C under rapid temperature decrease. • Pejus occured after a thermal challenge following 45 days acclimation at 18 °C. • Inshore waters' invasion may slow down due to cold winter sea surface temperature. [ABSTRACT FROM AUTHOR]
- Published
- 2020
- Full Text
- View/download PDF
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