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811.
Improved analysis of a bearingless switched reluctance motor   总被引:4,自引:0,他引:4  
Bearingless switched reluctance motors, which can control rotor radial positions with magnetic force, have been proposed. Bearingless switched reluctance motors have combined characteristics of switched reluctance motors and magnetic bearings. Production of radial force for rotor shaft magnetic suspension is explained with differential stator windings. Mathematical relations between motor currents and radial force are derived by considering cross coupling and fringing fluxes. Theoretical relationships are verified with experimental results at partial overlap positions  相似文献   
812.
813.
This paper presents a method for automatically generating sound effects for an animation of branches and leaves moving in the wind. Each tree is divided into branches and leaves, and an independent sound effect generation process is employed for each element. The individual results are then compounded into one sound effect. For the branches, we employ an approach based on the frequencies of experimentally obtained Karman vortex streets. For the leaves, we use the leaf blade state as the input and assume a virtual musical instrument that uses wave tables as the sound source. All computations can be performed independently for each frame step. Therefore, each frame step can be executed on completion of the animation step. The results of the implementation of the approach are presented and it is shown that the process offers the possibility of real‐time operation through the use of parallel computing techniques. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
814.
Numerous literatures have shown the advantages of Pickering emulsion (PE) for the delivery of bioactive ingredients in the fields of food, medicine, and cosmetics, among others. On this basis, the multi-loading mode of bioactives (internal phase encapsulation and/or loading at the interface) in small molecular bioactives nanocrystal-stabilized PE (BNC-PE) enables them higher loading efficiencies, controlled release, and synergistic or superimposed effects. Therefore, BNC-PE offers an efficacious delivery system. In this review, we briefly summarize BNC-PE fabrication and characterization, with a focus on the processes of possible evolution and absorption of differentially applied BNC-PE when interacting with the body. In addition, methods of monitoring changes and absorption of BNC-PE in vivo, from the nanomaterial perspective, are also introduced. The purpose of this review is to provide an accessible and comprehensive methodology for the characterization and evaluation of BNC-PE after formulation and preparation, especially in relation to biological assessment and detailed mechanisms throughout the absorption process of BNC-PE in vivo.  相似文献   
815.
The formation of ƞ phase induced by the C-loss for the laser powder bed fusion (LPBF) of WC–Co cemented carbides largely deteriorates the fracture toughness. The current approach of mixing C additive into powder cannot mitigate the ƞ phase formation. This study proposed a new carbon compensation strategy of coating carbon resource on powder surface by fluidized bed chemical vapor deposition to address this issue. C nanoparticles and carbon nanotubes (CNTs) were selectively deposited on WC–Co powder to make uniform C- and CNTs-coated powders by tuning the deposition temperature. Compared with CNTs-coated powder and C–WC–Co powder mixtures, the C-coated powder was more effective in impeding the ƞ phase formation because it had higher reactivity and stronger dissolution ability to compensate the C-loss in the Co–W–C liquid. However, the single-carbon compensation was not enough to eliminate the ƞ phase due to the extreme nonequilibrium characteristics of LPBF, which required secondary heat treatment. The conventional heat treatment procedure of 1000°C for 3 h eliminated the ƞ phase for the C-coated powder but failed for the C–WC–12Co powder mixtures. Because of the absence of ƞ phase, the heat-treated sample made from C-coated powder exhibited the highest transverse rupture strength.  相似文献   
816.
Optimizing the concentration of molybdenum incorporated in a borosilicate glass matrix is essential in the vitrification of high-level radioactive waste. However, the incorporation limit of MoO3 in fundamental borosilicate systems has been rarely correlated with the local structure of the molybdenum cations. This study investigates the variations in the incorporation limit of MoO3 in ternary sodium borosilicate glass upon varying the B2O3/(SiO2 + B2O3) ratio (i.e., B). The incorporation limit of MoO3 was less than 3 mol% in the low-B region (B < 0.7), where molybdenum cations mainly existed as [MoO4]2−. However, when B was higher than 0.85, the incorporation limit was higher than 6 mol%, and the Raman spectra indicated the presence of octahedrally coordinated molybdenum cations, essential to stabilize the Mo–O–Mo linkage. The variation in the local structure of molybdenum cations can be explained by the available amount of non-framework cations compensating for the negative charge near [MoO4]2−. These results allow the development of glass compositions with a high incorporation limit of MoO3 simply by controlling the local structure near the molybdenum cations.  相似文献   
817.
This paper describes the generation and rendering of three‐dimensional (3D) surface cellular automata (CA). Our model's main advantage is that it gives direct texturing simulation based on the actual shape of any triangulated input object. We first introduce general CA concepts and summarize works in the literature. We then describe our 3D surface CA method, emphasizing how it avoids potential problems in data structure and rendering steps. We then detail, two examples of specific 3D surface CA with their respective cell structures and corresponding computer graphics images. Copyright © 1999 John Wiley & Sons, Ltd.  相似文献   
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