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排序方式: 共有222条查询结果,搜索用时 15 毫秒
1.
Infiltration systems are frequently used as an option to manage urban storm drainage. By reducing flows and volumes in downstream sewers or in surface waters, they decrease the overflows and make it possible to recharge groundwater. They come in various forms with different uses; therefore, their performance is diverse and integrates multiple aspects. Consequently, a multicriteria approach was developed in order to quantify the performance of these systems and to help in decision making problems. For that purpose, a list of performance indicators integrating technical, economical, environmental and social aspects was developed. The performances were defined with the help of a working group composed of engineers from different technical or strategic departments from Greater Lyon and researchers from different fields. The paper presents the last version of the performance indicators tested according to a set of quality requirements: availability of data, relevance, fidelity, precision, sensitivity/robustness. This critical review of the set of indicators has led us to redefine a certain number of indicators, identify numerous biases and allow putting forward general instructions for criterion or indicator construction. The last phase is to propose multicriteria decision aid methods; a procedure using ELECTRE methods should be used. 相似文献
2.
van de Kamp M.M.J.L. Tervonen J.K. Salonen E.T. Baptista J.P.V. 《Electronics letters》1996,32(12):1074-1075
The prediction models for scintillation variance of ITU-R and Karasawa et al. (1988) are compared to measurements on a time base which is much shorter than originally considered for these models. It is shown that even after averaging over just three days, a good correlation with the measured variance is found. Both models predict higher scintillation variance than is measured at 19.8 GHz on a 12.7° elevation path in Kirkkonummi, Finland 相似文献
3.
Hugo Feitosa de Figueirêdo Yuri Almeida Lacerda Anselmo Cardoso de Paiva Marco Antonio Casanova Cláudio de Souza Baptista 《Multimedia Tools and Applications》2012,59(1):279-305
The recent popularity of digital cameras has posed a new problem: how to efficiently store and retrieve the very large number
of digital photos captured and chaotically stored in multiple locations without any annotation. This paper proposes an infrastructure,
called PhotoGeo, which aims at helping users with the people photo annotation, event photo annotation, storage and retrieval
of personal digital photos. To achieve the desired objective, PhotoGeo uses new algorithms that make it possible to annotate
photos with the key metadata to facilitate their retrieval, such as: the people who were shown in the photo (who); where it was captured (where); the date and time of capture (when); and the event that was captured. The paper concludes with a detailed evaluation of these algorithms. 相似文献
4.
Rinaldo Gregorio Matheus Rigobelo Chaud Wilson Nunes Dos Santos Joo Baptista Baldo 《应用聚合物科学杂志》2002,85(7):1362-1369
This study presents an investigation of the effect of the different crystalline phases of each blend component on miscibility when blending poly(vinylidene fluoride) (PVDF) and its copolymer poly[(vinylidene fluoride)‐ran‐trifluorethylene] [P(VDF–TrFE)] containing 72 mol % of VDF. It was found that, when both components crystallized in their ferroelectric phase, the PVDF showed a strong effect on the crystallinity and phase‐transition temperature of the copolymer, indicating partial miscibility in the crystalline state. On the other hand, immiscibility was observed when both components, after melting, were crystallized in their paraelectric phase. In this case, however, a decrease in crystallization temperatures suggested a strong interaction between monomers in the liquid state. Blend morphologies indicated that, in spite of the lack of miscibility in the crystalline state, there is at least miscibility between PVDF and P(VDF–TrFE) in the liquid state, and that a very intimate mixture of the two phases on the lamellar level can be maintained upon crystallization. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 85: 1362–1369, 2002 相似文献
5.
V. M. Ferreira J. L. Baptista S. Kamba J. Petzelt 《Journal of Materials Science》1993,28(21):5894-5900
Magnesium titanate (MgTiO3) powder was prepared by a chemical route (Pechini method) and different dopants were added to prepare several compositions. These pure and doped compositions were sintered in air and dense ceramics were obtained. The pure MgTiO3 samples were also subjected to different heat treatments during sintering. Complex permittivity spectra of ceramic samples were determined by various techniques in the 109–1014 Hz range. These techniques included infrared spectroscopy in transmission and reflectivity modes and microwave dielectric measurements. Extrapolation to microwave frequencies from infrared data, according to the proportionality (v) v, agrees quite well with the microwave data measured at 8 GHz and it is a useful procedure to estimate intrinsic microwave losses. Fast cooling from high temperatures of MgTiO3 samples increased dielectric loss, probably due to a structural disorder. Dopants have two types of effect depending on whether they form a distinct second phase or a solid solution with MgTiO3. In this last case intrinsic losses are strongly affected. 相似文献
6.
Paulo Santos Diogo Peixoto Inês Ferreira Ricardo Passos Pedro Pires Marco Simes Pedro Pouso-Ferreira Teresa Baptista Benjamín Costas 《International journal of molecular sciences》2022,23(3)
Photobacteriosis is a septicaemic bacterial disease affecting several marine species around the globe, resulting in significant economic losses. Although many studies have been performed related to the pathogen virulence and resistance factors, information regarding the host defence mechanisms activated once an infection takes place is still scarce. The present study was designed to understand innate immune responses of farmed juvenile gilthead seabream (Sparus aurata) after Photobacterium damselae subsp. piscicida (Phdp) infection. Therefore, two groups of seabream juveniles were intraperitoneally injected with 100 µL of PBS (placebo) or 100 µL of exponentially growing Phdp (1 × 106 CFU/mL; infected). The blood, plasma, liver, and head kidney of six fish from each treatment were sampled immediately before infection and 3, 6, 9, 24 and 48 h after infection for the broad screening of fish immune and oxidative stress responses. Infected animals presented marked anaemia, neutrophilia and monocytosis, conditions that are correlated with an increased expression of genes related to inflammation and phagocytic activity. Similar studies with different fish species and bacteria can be useful for the definition of health biomarkers that might help fish farmers to prevent the occurrence of such diseases. 相似文献
7.
Free-radical scavenging capacity and reducing power of wild edible mushrooms from northeast Portugal: Individual cap and stipe activity 总被引:6,自引:0,他引:6
Isabel C.F.R. Ferreira Paula Baptista Miguel Vilas-Boas Lillian Barros 《Food chemistry》2007,100(4):1511-1516
The antioxidant properties of two wild edible mushroom species from the northeast of Portugal, Lactarius deliciosus (L.) Gray and Tricholoma portentosum (Fr.) Quél., were evaluated. Methanolic extracts from the entire mushroom, the cap and the stipe, separately, were screened for their reducing power and free radical scavenging capacity by chemical assays. The total phenolic content was determined, in order to assess its effect on the extract’s antioxidant activity. Both two species showed antioxidant potential; but L. deliciosus proved to be more active. The portion of the mushroom used had an influence on the results obtained, with the cap methanolic extracts exhibiting the greatest antioxidant effect. 相似文献
8.
Salivary Amylase Induction by Tannin-Enriched Diets as a Possible Countermeasure Against Tannins 总被引:1,自引:0,他引:1
da Costa G Lamy E Capela e Silva F Andersen J Sales Baptista E Coelho AV 《Journal of chemical ecology》2008,34(3):376-387
Tannins are characterized by protein-binding affinity. They have astringent/bitter properties that act as deterrents, affecting
diet selection. Two groups of salivary proteins, proline-rich proteins and histatins, are effective precipitators of tannin,
decreasing levels of available tannins. The possibility of other salivary proteins having a co-adjuvant role on host defense
mechanisms against tannins is unknown. In this work, we characterized and compared the protein profile of mice whole saliva
from animals fed on three experimental diets: tannin-free diet, diet with the incorporation of 5% hydrolyzable tannins (tannic
acid), or diet with 5% condensed tannins (quebracho). Protein analysis was performed by one-dimensional gel electrophoresis combined with Matrix-Assisted Laser Desorption Ionization-Time
of Flight mass spectrometry to allow the dynamic study of interactions between diet and saliva. Since abundant salivary proteins
obscure the purification and identification of medium and low expressed salivary proteins, we used centrifugation to obtain
saliva samples free from proteins that precipitate after tannin binding. Data from Peptide Mass Fingerprinting allowed us
to identify ten different proteins, some of them showing more than one isoform. Tannin-enriched diets were observed to change
the salivary protein profile. One isoform of α-amylase was overexpressed with both types of tannins. Aldehyde reductase was
only identified in saliva of the quebracho group. Additionally, a hypertrophy of parotid salivary gland acini was observed
by histology, along with a decrease in body mass in the first 4 days of the experimental period.
G. da Costa and E. Lamy have contributed equally to this work. 相似文献
9.
10.
The main objective of this research is to analyze the impact of the market share increase of hydrogen based road vehicles in terms of energy consumption and CO2, on today's Portuguese light-duty fleet. Actual yearly values of energy consumption and emissions were estimated using COPERT software: 167112 TJ of fossil fuel energy, 12213 kton of CO2 emission and 141 kton of CO, 20 kton of HC, 46 kton of NOx and 3 kton of PM. These values represent 20–40% of countries total emissions. Additionally to base fleet, three scenarios of introduction of 10–30% fuel cell vehicles including plug-in hybrids configurations were analysed. Considering the scenarios of increasing hydrogen based vehicles penetration, up to 10% life cycle energy consumption reduction can be obtained if hydrogen from centralized natural gas reforming is considered. Full life cycle CO2 emissions can also be reduced up to 20% in these scenarios, while local pollutants reach up to 85% reductions. For the purpose of estimating road vehicle technologies energy consumption and CO2 emissions in a full life cycle perspective, fuel cell, conventional full hybrids and hybrid plug-in technologies were considered with diesel, gasoline, hydrogen and biofuel blends. Energy consumption values were estimated in a real road driving cycle and with ADVISOR software. Materials cradle-to-grave life cycle was estimated using GREET database adapted to Europe electric mix. The main conclusions on CO2 full life cycle analysis is that light-duty vehicles using fuel cell propulsion technology are highly dependent on hydrogen production pathway. The worst scenario for the current Portuguese and European electric mix is hydrogen produced from on-site electrolysis (in the refuelling stations). In this case full life cycle CO2 is 270 g/km against 190 g/km for conventional Diesel vehicle, for a typical 150,000 km useful life. 相似文献