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71.
Modern human societies have evolved into an almost entirely connected world, giving place to a remarkable increase in social interactions. In this new context and because of the globalization of all human activities, the collective participation in decision‐making processes takes an increasingly prominent role. In this paper, a method for group decision making from a set of imprecise opinions called “moviQuest Decision Making” (MQDM), is presented. This method allows to integrate the opinions of heterogeneous groups of agents in a structured social network along a sequence of voting rounds for collective decision making. 相似文献
72.
Ana M. Fernandes Rita C. Pereira Jorge Sousa Bernardo B. Carvalho Joaquim M.F. dos Santos Vasily Kiptily Carlos M.B.A. Correia Carlos A.F. Varandas 《Fusion Engineering and Design》2012,87(12):2156-2160
The duration of a single plasma discharge in the next generation of fusion experiments will be much longer than in the present devices. Storing all raw data acquired in each discharge will be more difficult and the high rates achieved by the new digitizers are already contributing to storage overload. This gap can be mitigated by real time (RT) analysis and compression, using devices such as field programmable gate arrays (FPGAs) capable to transfer and process data on the fly. However, to ensure a correct RT analysis, the FPGA algorithm must be adapted to the signal to be acquired. Since minor changes in signal shape may require significant algorithm modifications, it is important to know in advance the signal attributes. For that reason, the availability of more than one RT algorithm, especially during commissioning of new sub-systems and during campaigns with relevant changes in diagnostic conditions, is advantageous. This paper presents an implementation using two RT algorithms processing simultaneously, developed for the gamma-ray and hard X-ray diagnostics of the Joint European Torus (JET). Both algorithms perform pulse height analysis with pile-up rejection. While the first algorithm is suitable for Gaussian shaped pulses, the second is suitable for exponential signals. The algorithms are selectable by the user, during discharge configuration. Tests with radioactive sources made in JET are presented. 相似文献
73.
In order to formulate mathematical conjectures likely to be true, a number of base cases must be determined. However, many combinatorial problems are NP-hard and the computational complexity makes this research approach difficult using a standard brute force approach on a typical computer. One sample problem explored is that of finding a minimum identifying code. To work around the computational issues, a variety of methods are explored and consist of a parallel computing approach using MATLAB, an adiabatic quantum optimization approach using a D-Wave quantum annealing processor, and lastly using satisfiability modulo theory (SMT) and corresponding SMT solvers. Each of these methods requires the problem to be formulated in a unique manner. In this paper, we address the challenges of computing solutions to this NP-hard problem with respect to each of these methods. 相似文献
74.
Jesus Israel Barraza-Fierro Bernardo Campillo-Illanes Ximing Li Homero Castaneda 《Metallurgical and Materials Transactions A》2014,45(9):3981-3994
Different thermomechanical treatments were applied to a high strength low carbon steel with a novel chemical composition. As a result, three different microstructures were produced with dissimilar mechanical and corrosion properties. Subsequently, a tempering heat treatment was applied to redistribute the phases in the steel. Microstructure A with 56 pct martensite and 32 pct bainite presented high strength but medium ductility; microstructure C with 95 pct ferrite and 3 pct martensite/austenite resulted in low strength and high ductility, and finally microstructure B with 98 pct bainite and 2 pct martensite/austenite resulted in high strength and ductility. Alternatively the corrosion behavior obtained by polarization curves was characterized in 0.1 M H2SO4, 3 M H2SO4, 3.5 wt pct NaCl, and NS4 solutions resulting in similar magnitudes, while the corrosion behavior acquired by electrochemical impedance spectroscopy had slightly differences in 3 M H2SO4. 相似文献
75.
Polypropylene tensile bars were hot plate welded and analyzed by microscopy and mechanical tests. The welding process caused significant modifications to the microstructure and shape of the bars at the weld zone. The weld morphology was affected by both the welding parameters and the thermal history of the components. Oriented textures, coarse spherulites, voids or sharp notches occurring at the beads are the key morphological factors that affect the weld quality. Weld performance is dependent upon the type of testing method used. A tensile impact test has been shown to be potentially useful for quality control, as the fracture behavior is affected by the overall morphoiogy. 相似文献
76.
Starch‐poly(acrylamide‐co‐2‐acrylamido‐2‐methylpropanesulfonic acid) graft copolymers prepared by reactive extrusion
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Graft copolymers of starch with acrylamide and 2‐acrylamido‐2‐methylpropanesulfonic acid (AMPS) were prepared by reactive extrusion in a twin‐screw extruder. The weight ratio of total monomer to starch was fixed at 1 : 3, while the molar fraction of AMPS in the monomer feed ranged from 0 to 0.119. Monomer to polymer conversions were 85% or greater, with grafting efficiencies of 68% (highest AMPS content) to 85% (no AMPS). Absorbency in distilled water at pH 7 increased linearly with the mole fraction AMPS in the grafted polymer, while absorbencies in 0.9% NaCl were independent of AMPS content. When swollen in water/ethanol mixtures, swelling decreased gradually with increasing ethanol volume fraction, followed by a large decrease over a narrow ethanol concentration. This behavior is similar to that observed for AMPS‐acrylamide gels. The swelling properties suggest these graft copolymers may have applications as responsive materials. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42405. 相似文献
77.
Wesley Pacheco Calixto A. Paulo Coimbra Jesus Carlos da Mota Marcel Wu Wander G. da Silva Bernardo Alvarenga Leonardo da Cunha Brito Aylton Jose Alves Elder Geraldo Domingues Daywes Pinheiro Neto 《International Journal of Numerical Modelling》2015,28(1):78-95
This work presents a genetic operator developed from mathematical methods of curve extrapolation applied in solving problems in geoelectrical prospection. This operator will assist the production of fitter individuals in the population of a genetic algorithm in which inherent patterns of the best individuals of each generation are recognized. The proposed operator in conjunction with a real‐coded genetic algorithm is compared to five alternative optimization techniques known and used in the application to problems in geoelectrical prospection. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
78.
Increased HDL Size and Enhanced Apo A-I Catabolic Rates Are Associated With Doxorubicin-Induced Proteinuria in New Zealand White Rabbits
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Victoria López-Olmos Elizabeth Carreón-Torres María Luna-Luna Cristobal Flores-Castillo Miriam Martínez-Ramírez Rocío Bautista-Pérez Martha Franco Julio Sandoval-Zárate Francisco-Javier Roldán Alberto Aranda-Fraustro Elizabeth Soria-Castro Mónica Muñoz-Vega José-Manuel Fragoso Gilberto Vargas-Alarcón Oscar Pérez-Méndez 《Lipids》2016,51(3):311-320
The catabolism and structure of high‐density lipoproteins (HDL) may be the determining factor of their atheroprotective properties. To better understand the role of the kidney in HDL catabolism, here we characterized HDL subclasses and the catabolic rates of apo A‐I in a rabbit model of proteinuria. Proteinuria was induced by intravenous administration of doxorubicin in New Zealand white rabbits (n = 10). HDL size and HDL subclass lipids were assessed by electrophoresis of the isolated lipoproteins. The catabolic rate of HDL‐apo A‐I was evaluated by exogenous radiolabelling with iodine‐131. Doxorubicin induced significant proteinuria after 4 weeks (4.47 ± 0.55 vs. 0.30 ± 0.02 g/L of protein in urine, P < 0.001) associated with increased uremia, creatininemia, and cardiotoxicity. Large HDL2b augmented significantly during proteinuria, whereas small HDL3b and HDL3c decreased compared to basal conditions. HDL2b, HDL2a, and HDL3a subclasses were enriched with triacylglycerols in proteinuric animals as determined by the triacylglycerol‐to‐phospholipid ratio; the cholesterol content in HDL subclasses remained unchanged. The fractional catabolic rate (FCR) of [131I]‐apo A‐I in the proteinuric rabbits was faster (FCR = 0.036 h?1) compared to control rabbits group (FCR = 0.026 h?1, P < 0.05). Apo E increased and apo A‐I decreased in HDL, whereas PON‐1 activity increased in proteinuric rabbits. Proteinuria was associated with an increased number of large HDL2b particles and a decreased number of small HDL3b and 3c. Proteinuria was also connected to an alteration in HDL subclass lipids, apolipoprotein content of HDL, high paraoxonase‐1 activity, and a rise in the fractional catabolic rate of the [131I]‐apo A‐I. 相似文献
79.
Mauro Marangoni Lukas Arnout Lieven Machiels Lieven Pandelaers Enrico Bernardo Paolo Colombo Yiannis Pontikes 《Journal of the American Ceramic Society》2016,99(6):1985-1991
The present paper deals with the synthesis of porous, sintered glass‐ceramics obtained at temperatures below 1150°C, originating from inorganic polymers based on fayalite slag. Firing led to the evaporation of water, dehydroxylation, and oxidation of Fe2+ above 345°C. For heating >700°C, the Si–O stretching band shifted from the 1160 and 750 cm?1 to the 1255 and 830 cm?1 region, due to a structural reorganization of the amorphous phase, whereas Fe–O bands appeared at 550 cm?1. The final microstructure consisted predominantly of an amorphous phase, hematite, and franklinite. The open porosity and compressive strength decreased and increased, respectively, as the firing temperature increased. The final values suggest properties comparable to that of structural lightweight concrete, still, the materials synthesized herein, are lighter, and made primarily from secondary resources. 相似文献
80.
Direct Ink Writing of a Preceramic Polymer and Fillers to Produce Hardystonite (Ca2ZnSi2O7) Bioceramic Scaffolds
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Andrea Zocca Giorgia Franchin Hamada Elsayed Emilia Gioffredi Enrico Bernardo Paolo Colombo 《Journal of the American Ceramic Society》2016,99(6):1960-1967
The direct ink writing of an ink composed of a preceramic polymer and fillers was used to produce hardystonite (Ca2ZnSi2O7) bioceramic scaffolds. Suitable formulations were developed for the extrusion of fine filaments (350 μm diameter) through a nozzle. The preceramic polymer was employed with the double purpose of contributing to the rheology of the ink by increasing its viscosity and of forming the hardystonite phase upon heat treatment by reacting with the fillers. A control of the rheology is essential when spanning features have to be produced, and therefore the main rheological characteristics of the inks were measured (flow curves, dynamic oscillation tests, viscosity recovery tests) and compared to models reported in the literature. Highly porous scaffolds (up to 80% total porosity) were produced and heat treated in air or in nitrogen atmosphere. The influence of the heat‐treatment atmosphere on the morphology, crystalline phase assemblage, and compressive strength of the scaffolds was investigated. 相似文献