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1.
Axel Carlier Amaia Salvador Ferran Cabezas Xavier Giro-i-Nieto Vincent Charvillat Oge Marques 《Multimedia Tools and Applications》2016,75(23):15901-15928
There has been a growing interest in applying human computation – particularly crowdsourcing techniques – to assist in the solution of multimedia, image processing, and computer vision problems which are still too difficult to solve using fully automatic algorithms, and yet relatively easy for humans. In this paper we focus on a specific problem – object segmentation within color images – and compare different solutions which combine color image segmentation algorithms with human efforts, either in the form of an explicit interactive segmentation task or through an implicit collection of valuable human traces with a game. We use Click’n’Cut, a friendly, web-based, interactive segmentation tool that allows segmentation tasks to be assigned to many users, and Ask’nSeek, a game with a purpose designed for object detection and segmentation. The two main contributions of this paper are: (i) We use the results of Click’n’Cut campaigns with different groups of users to examine and quantify the crowdsourcing loss incurred when an interactive segmentation task is assigned to paid crowd-workers, comparing their results to the ones obtained when computer vision experts are asked to perform the same tasks. (ii) Since interactive segmentation tasks are inherently tedious and prone to fatigue, we compare the quality of the results obtained with Click’n’Cut with the ones obtained using a (fun, interactive, and potentially less tedious) game designed for the same purpose. We call this contribution the assessment of the gamification loss, since it refers to how much quality of segmentation results may be lost when we switch to a game-based approach to the same task. We demonstrate that the crowdsourcing loss is significant when using all the data points from workers, but decreases substantially (and becomes comparable to the quality of expert users performing similar tasks) after performing a modest amount of data analysis and filtering out of users whose data are clearly not useful. We also show that – on the other hand – the gamification loss is significantly more severe: the quality of the results drops roughly by half when switching from a focused (yet tedious) task to a more fun and relaxed game environment. 相似文献
2.
Testing of carbon supported Pd-Pt electrocatalysts for methanol electrooxidation in direct methanol fuel cells 总被引:1,自引:0,他引:1
Francisco Alcaide Garbiñe ÁlvarezPere L. Cabot Hans-Jürgen GrandeOscar Miguel Amaia Querejeta 《International Journal of Hydrogen Energy》2011,36(7):4432-4439
In the present work, a detailed characterization of the electrochemical behavior of carbon supported Pd-Pt electrocatalysts toward CO and methanol electrooxidation in direct methanol fuel cells is reported. Technical electrodes containing an ionomer in their catalyst layer were prepared for this purpose. CO and methanol electrooxidation reactions were used as test reactions to compare the electrocatalytic behavior of bimetallic supported nanoparticles in acidic liquid electrolyte and in solid polymer electrolyte (real fuel cell operating conditions). Experimental results in both environments are consistent and show that the electrochemical behavior of carbon supported Pd-Pt depends on their composition, giving the best performance in direct methanol single fuel cell with a Pd:Pt atomic ratio of 25:75 in the catalyst. 相似文献
3.
The evolution of smart vehicles has widened the application opportunities for vehicular ad hoc networks. In this context, the routing issue is still one of the main challenges regarding to the performance of the network. Although there are multiple ad hoc routing proposals, the traditional general-purpose approaches do not fit the distinctive properties of vehicular network environments. New routing strategies must complement the existing protocols to improve their performance in vehicular scenarios. This paper introduces a novel intelligent routing technique that makes decisions in order to adaptively adjust its operation and obtain a global benefit. The nodes sense the network locally and collect information to feed the cognitive module which will select the best routing strategy, without the need of additional protocol message dissemination or convergence mechanism. 相似文献
4.
Peroxisome proliferators comprise a heterogeneous group of compounds known for their ability to cause massive proliferation of peroxisomes and liver carcinogenesis in rodents. In recent years it has become evident that other animals may be threatened by peroxisome proliferators, in particular aquatic organisms living in coastal and estuarine areas. These animals are exposed to a variety of pollutants of industrial, agricultural and urban origin which are potential peroxisome proliferators. Both laboratory and field studies have shown that phthalate ester plasticizers, PAHs and oil derivatives, PCBs, certain pesticides, bleached kraft pulp and paper mill effluents, alkylphenols and estrogens provoke peroxisome proliferation in different fish or bivalve mollusc species. The response appears to be mediated by peroxisome-proliferator activated receptors, members of the nuclear receptor family, recently cloned in fish. Based on these results it is proposed that peroxisome proliferation could be used as a biomarker of exposure to a variety of pollutants in environmental pollution assessment. This is illustrated by a case study in which mussels, used worldwide as sentinels of environmental pollution, were transplanted from reference to contaminated areas and vice versa. In mussels native to an area polluted with PAHs and PCBs, peroxisomal acyl-CoA oxidase (AOX) activity and peroxisomal volume density were 2-3 fold and 5-fold higher, respectively, compared to the reference site. When animals were transplanted to the polluted station, with increased concentration of organic xenobiotics, a concomitant significant increase of AOX was recorded. Conversely, in animals transplanted to the cleaner station, AOX activity and peroxisomal volume density decreased significantly. These results indicate that peroxisome proliferation is a rapid (i.e., two days) and reversible response to pollution in mussels. Before peroxisome proliferation can be implemented as a biomarker in biomonitoring programs, a well-defined protocol should be established and validated in intercalibration and quality assurance programmes. Furthermore, the influence of biotic and abiotic factors, some of which are known to affect peroxisome proliferation (season, tide level, interpopulation and interindividual variability), should be taken into consideration. The possible hepatocarcinogenic effects as well as the potential adverse effects on reproduction, development, and growth of peroxisome proliferators are unknown in aquatic organisms, thus providing a challenge for future investigations. 相似文献
5.
J.‐L. Molina‐Cano A. Rubi E. Igartua P. Gracia J.‐L. Montoya 《Journal of the Institute of Brewing》2000,106(2):111-116
Malt extract yield (EXT) and barley protein content (BPROT) data from 346 EBC trials located across all the EBC countries, and composed of many different varieties, from the years 1980, 1982 to 1990, inclusive, and 1993 to 1995, thus covering 13 seasons, were used to detect regional trends affecting the negative correlation between these two variables. Quadratic curves were fitted to data from each European region (North, Central, West and South), all of which showed very high coefficients of determination (r2). A common trend in all regions, and also in the overall European analysis, was of EXT decreasing when BPROT increased, although the extent of decrease varied among the regions. Two different geographical patterns of variation in EXT with changes in BPROT have been observed, on the one hand those of the Iberian Peninsula and West region, and on the other, those of the North and Central regions. In the first case, the rate of decrease in EXT was almost constant across the full range of variation of BPROT, whereas, in the second case, the decrease in EXT grew progressively with increases in BPROT. Therefore, although “Bishop's law” on EXT decrease with BPROT increase holds true as a general statement, it would be necessary to take climatic differences into account when estimating EXT values from BPROT data. 相似文献
6.
Friction coefficient in FZG gears lubricated with industrial gear oils: Biodegradable ester vs. mineral oil 总被引:2,自引:1,他引:1
R. Martins J. Seabra A. Brito Ch. Seyfert R. Luther A. Igartua 《Tribology International》2006,39(6):512-521
Two industrial gear oils, a reference paraffinic mineral oil with a special additive package for extra protection against micropitting and a biodegradable non-toxic ester, were characterized in terms of their physical properties, wear properties and chemical contents and compared in terms of their power dissipation in gear applications [Höhn BR, Michaelis K, Döbereiner R. Load carrying capacity properties of fast biodegradable gear lubricants. J STLE Lubr Eng 1999; Höhn BR, Michaelis K, Doleschel A. Frictional behavior of synthetic gear lubricants. Tribology research: from model experiment to industrial problem. Elsevier 2001; Martins R, Seabra J, Seyfert Ch, Luther R, Igartua A, Brito A. Power Loss in FZG gears lubricated with industrial gear oils: biodegradable ester vs. mineral oil. Proceedings of the 31th Leeds-Lyon symposium on tribology. Elsevier; to be published; Weck M, Hurasky-Schonwerth O, Bugiel Ch. Service behaviour of PVD-coated gearing lubricated with biodegradable synthetic ester oils. VDI-Berichte Nr.1665 2002.]. The viscosity–temperature behaviors are compared to describe the feasible operating temperature range.Standard tests with the Four-Ball machine and the FZG test rig [Winter H, Michaelis K. FZG gear test rig—desciption and possibilities. In: Coordinate European Council second international symposium on the performance evaluation of automotive fuels and lubricants; 1985.] characterize the wear protection properties. Biodegradability and toxicity tests are performed in order to assess the biodegradability and toxicity of the two lubricants.Power loss gear tests are performed on the FZG test rig using type C gears, for wide ranges of the applied torque and input speed, in order to compare the energetic performance of the two industrial gear oils. Lubricant samples are collected during and at the end of the gear tests [Hunt TM. Handbook of wear debris analysis and particle detection in liquids. UK: Elsevier Science; 1993.] and are analyzed by Direct Reading Ferrography (DR3) in order to evaluate and compare the wear particles concentration indexes of both lubricants.An energetic model of the FZG test gearbox is developed, integrating the mechanisms of power dissipation and heat evacuation, in order to determine its operating equilibrium temperature. An optimization routine allows the evaluation of the friction coefficient between the gear teeth for each lubricant tested, correlating experimental and model results.For each lubricant and for the operating conditions considered, a correction expression is presented in order to adjust the friction coefficient proposed by Höhn et al. [Höhn BR, Michaelis K, Vollmer T. Thermal rating of gear drives: balance between power loss and heat dissipation. AGMA Technical Paper; October 1996. pp 12. ISBN: 1-55589-675-8.] to the friction coefficient exhibited by these lubricants. The influence of each lubricant on the friction coefficient between the gear teeth is discussed taking into consideration the operating torque and speed and the stabilized operating temperature. 相似文献
7.
C sar Mart n-G mez Amaia Zuazua-Ros Javier Bermejo-Busto Enrique Baquero Rafael Miranda Cristina Sanz 《建筑学研究前沿(英文版)》2019,8(1):17-31
The strategies for thermal regulation and environmental control found in nature are countless. In this article, a parallelism between animals and building energy systems is defined in order to identify and emphasize the immediate opportunities that biomimicry offers for future research. The motivation was the need to find alternative solutions to tackle problems mainly in the efficiency of heating, ventilation and cooling systems. Due to the wide range of possibilities offered by animals, this study is largely limited to the strategies that cold-blooded animals have developed through evolutionary adaptation to the environment. The method used for the analysis is based on a solution-based approach. Firstly, different animal thermoregulation strategies are defined (biologicaldomain). Then the strategy is analyzed and classified into three categories. This classification is essential in order to formulate the parallelism with building systems (transfer phase). The final step is to identify the potential implementation (technologicaldomain). This approach has been seen to be useful in creating new research opportunities based on biomimicry. In addition, suitable solutions arising from multidisciplinary team research are presented as promising answers to the challenges that building energy systems face nowadays. 相似文献
8.
María J. Unzu Harold A. S. Schoonbrood Jos M. Asua Amaia Montoya Goi David C. Sherrington Katrin Sthler Karl-Heinz Goebel Klaus Tauer Marie Sjberg Krister Holmberg 《应用聚合物科学杂志》1997,66(9):1803-1820
Several polymerizable surfactants (surfmers) have been used in the semi-continuous emulsion copolymerization of styrene, butyl acrylate, and acrylic acid. Three of the (anionic) surfmers (sodium 11-crotonoyl undecan-1-yl sulfate, sodium 11-methacryloyl undecan-1-sulfate, and sodium sulfopropyl tetradecyl maleate) were prepared in house with purities between 53 and 82%. Physicochemical properties such as the critical micelle concentration, the adsorption isotherm, and the specific adsorption area were determined. The surfmers were then used with constant addition profiles in semicontinuous reactions, and the instantaneous conversions of the main monomers determined. The particle size, amount of coagulum, surface tension, and stability against electrolyte solutions of the latices were evaluated. Films were cast of some of the latices, and the visual appearance and water adsorption were assessed. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 66: 183–1820, 1997 相似文献
9.
Amaia Bastero Aurora Ruiz Carmen Claver Antonio Bella Barbara Milani Beln Moreno‐Lara FlixA. Jaln BlancaR. Manzano 《Advanced Synthesis \u0026amp; Catalysis》2005,347(6):839-846
The CO/tert‐butylstyrene/ethylene terpolymerization catalyzed by Pd‐(N‐N′) complexes was studied. The results evidence that the olefin preferentially inserted in the terpolymer chain is strictly related to the nature of the nitrogen ligand, mainly to its steric constraints, and not to the kind of ligand. Indeed, slight variations in the backbone of the nitrogen ligands coordinated to palladium allow for the synthesis of terpolymers with a controlled composition. 相似文献
10.
Flora Faleschini Amaia Santamaria Mariano Angelo Zanini José-Tomás San José Carlo Pellegrino 《Materials and Structures》2017,50(3):170
This paper deals with the bond between steel reinforcement and recycled aggregate concrete, including Electric arc furnace (EAF) slag as full replacement of natural coarse aggregates. Pull-out tests were carried out according to RILEM standard on specimens made with six concrete mixtures, characterized by different w/c ratios and types of aggregates. Plain and ribbed steel reinforcement bars were used to observe the influence of steel roughness. Experimental bond-slip relationships were analyzed, and results show similar bond mechanisms between the reference and EAF concrete specimens. Significant bond strength enhancement is observed in concretes with low w/c ratio, when EAF slag is used as recycled coarse aggregate. Experimental results in terms of bond strength were also compared to analytical predictions, obtained with empirical formulations. 相似文献