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991.
This paper addresses reliable and efficient calculation of the mode of a multivariate sample, which is a classical fusion function. In particular, we focus on the inputs given on the unit simplex, when aggregating elements of Atanassov intuitionistic fuzzy sets, interval-valued fuzzy sets and their extensions, as well as compositional data. We outline the use of a specially designed 2-additive fuzzy measures and the Choquet integral for the purposes of reducing computational complexity in higher dimensions. We present computational analysis and benchmark four different methods of density-based mode estimation. 相似文献
993.
A quantitative methodology for particle suspension assessment is presented. A new parameter, fmov/tot, the ratio of the mean number of moving particles to the total number of particles, is introduced to evaluate the minimum speed required to just suspend solids. This approach is tested to investigate the impact of impeller clearance on the minimum impeller speed, Njs, in a vessel when using a radial flow Rushton turbine. Flow patterns and power numbers obtained experimentally and computationally support the suspension findings. Image analysis is an appropriate method for determining Njs. Lowering the impeller clearance reduces the speed required for particle suspension with a change of flow pattern from a radial discharge with two loops to a single loop scouring the vessel base. The power number also falls markedly at the two‐to‐one loop transition as does the strain rate near the base. 相似文献
994.
A novel hot aerosol extinguishing agent (HAEA), which is the combination of pyrotechnics and flame retardant technology, was found to have great efficiency in extinguishing Class B fires. A mixture of P and P3N5, referred to as P90x, was chosen as the reductant, and phase stabilized ammonium nitrate was chosen as the oxidant. This paper describes a study of the effectiveness of this agent in extinguishing n‐heptane fires (ie, Class B fires). We determined that the best efficiency was 15 g/m3 for extinguishing n‐heptane fires, four times more efficient than a traditional agent. The efficiency increases as the mass fraction of P90x rises. We also identified the key difference between the novel extinguishing agent and the traditional agent. The former consists of an inorganic phosphorus compound, while the latter is mainly comprised of KOH. Consequently, their extinguishing mechanisms are different. The phosphorus oxide of the novel HAEAs is the leading component to extinguish fire, which is more effective than alkali salts. 相似文献
995.
996.
997.
He Shuilong Chen Keren Xu Enyong Ye Mingsong Wang Yanxue 《Journal of Mechanical Science and Technology》2021,35(10):4329-4341
Journal of Mechanical Science and Technology - This article introduces a rigid-flexible coupling calculation model based on a multi-platform integrated method to analyze and optimize the cab... 相似文献
998.
Chaojun Cui Ye Wang Xiangze Du Li Li Mouxiao Song Wenqing Zeng Guiying Li Changwei Hu 《International Journal of Hydrogen Energy》2021,46(40):20835-20847
xNi/HTASAO5 catalysts (x = 2.5, 3.3, 4.4, 5.8, 8.2) were prepared for CO2 reforming of methane. No crystalline nickel species formed on the catalysts with lower nickel content (≤4.4%), and large Ni0 crystallite formed on 5.8% (10 nm) and 8.2 wt%Ni/HTASAO5 (17 nm), whereas the surface concentration of Ce3+ decreased with Ni loading. The initial conversion of CH4 increased from 29.5% to 46.9% with Ni loading. The xNi/HTASAO5 (x ≤ 4.4%) performed stably in the reaction due to the presence of dispersed Ni species and high surface Ce3+ content without coke formation, however, 5.8% and 8.2 wt%Ni/HTASAO5 exhibited decreased activity with time on stream, because of the formation of large Ni particles with lower surface Ce3+, leading to carbon accumulation. Thus, CH4 conversion stabilized at about 43% and no carbon formed on 4.4 wt%Ni/HTASAO5 with optimum Ni loading. 相似文献
999.
Biao Tang Jian-Bo Li Jun-Liu Ye Huan Luo Yi-Tao Wang Bo Guan Yang-Fan Lu Xian-Hua Chen Kai-Hong Zheng Fu-Sheng Pan 《金属学报(英文版)》2022,35(12):1935
In this study, the deformable titanium (Ti) particles reinforced AZ91 composite was successfully prepared by powder metallurgy and subsequent extrusion. The mechanical properties and microstructural evolution of pure AZ91 and 5Ti/AZ91 composite were studied. The yield strength, ultimate tensile strength, and elongation of 5Ti/AZ91 composite are measured to be 212 MPa, 323 MPa, and 10.1%, respectively. Microstructure analysis revealed that Ti particles are elongated along the extrusion direction, forming a discontinuous strip Ti particles, fine precipitated Mg17Al12 phase inhibits dynamic recrystallization (DRX) behavior through Zener pinning effect and hinders the growth of matrix grains, resulting in refiner grains of 5Ti/AZ91 composite. Heterogeneous deformed Ti particles and magnesium (Mg) matrix to generate additional heterogeneous deformation-induced (HDI) strengthening. Heterogeneous deformation-induced strengthening mainly contributed to the increment of yield strength for 5Ti/AZ91 composite. 相似文献
1000.
Gang Wang Ke Ye Jiaqi Shao Yingying Zhang Kai Zhu Kui Cheng Jun Yan Guiling Wang Dianxue Cao 《International Journal of Hydrogen Energy》2018,43(19):9316-9325
Porous Ni2P nanoflower supported on nickel foam (Ni2P@Ni foam) electrodes are synthesized via a simple hydrothermal growth strategy accompanied with further phosphating treatment. The prepared electrodes are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX) and transmission electron microscopy (TEM). Electro-catalytic performances towards urea electro-oxidation are tested by cyclic voltammetry (CV), chronoamperometry (CA) coupled with electrochemical impedance spectroscopy (EIS). By phosphating Ni(OH)2 precursor, the final obtained Ni2P@Ni foam electrode presents a porous Ni2P nanoflower structure within abundant porosity, and so exposes a large amount of electro-catalytic active sites and electronic transmission channels to accelerate the interfacial reaction. Compared with Ni(OH)2@Ni foam precursor, the Ni2P@Ni foam catalyst exhibits more excellent electro-catalytic activity as well as lower onset oxidation potential. Remarkably, the Ni2P@Ni foam catalyst reaches a peak current density of 750 mA cm?2 with an onset oxidation potential of 0.24 V (vs. Ag/AgCl) accompanied by an excellent stability in 0.60 M urea with 5.00 M KOH solutions. Benefiting from the unique porous nanosheet structure, the as-synthesized Ni2P@Ni foam catalyst performs a highly enhanced catalytic behavior for alkaline urea electro-oxidation, indicating that the material can be hopefully applied in direct urea fuel cells. 相似文献