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141.
142.
Peihui Shao Neil F. Stewart 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2013,17(8):1425-1437
We consider operations on subdivision surfaces under the strict robustness requirement that these floating-point computations return an object with the same topological form as the true solution. The problems involved may however be ill-conditioned, and defined in terms of uncertain data, and even supplementary interval arithmetic may not ensure robustness. Trapping mechanisms are therefore proposed to resolve this difficulty. 相似文献
143.
Ke YANG Manqi LV 《材料科学技术学报》2007,23(3):333-336
An austenitic antibacterial stainless steel is reported in this paper. The very fine and dispersive ε-Cu precipitations in the matrix of the antibacterial steel after the antibacterial treatment endow the steel with antibacterial function. The antibacterial function is strong, long-term and broad-spectrum, and can be maintained even after repeated wear and long time dipping in water. The steel is safe for human body and could be used widely in daily application. 相似文献
144.
李科 《Canadian Metallurgical Quarterly》2011,(1)
实践是理论的根基和土壤.从实践视角审视科学发展观的科学内涵,可以提升科学发展观的学科地位.科学发展观是中国共产党在漫长实践中孕育出来的理论成果;是在实践背景下理论不断演绎提升的精华;其科学性为未来实践提供了理论支持. 相似文献
145.
146.
重整装置腐蚀类型有高温H2腐蚀、高温H2-H2S腐蚀、有机酸腐蚀、H2S-HCl-H2O腐蚀,针对不同类型的腐蚀,应采取相应的防腐蚀措施。 相似文献
147.
An investigation was carried out by numerical simulation on a wind turbine airfoil and a blunt trailing-edge airfoil with and without vortex generators (VGs), and the performance of the airfoils was analyzed. By the simulation of airfoil DU 91-W2-250 it was verified that the numerical method and model were credible. Based on this airfoil, a new one with a blunt trailing edge of 6% chord was blended by symmetrically adding thickness, and its characteristics curves were obtained through computing at key angle... 相似文献
148.
This paper presents a mechanics study of the variations with position and time of stresses within the dermis and epidermis of a human fingertip when it is loaded and slid over textured surfaces. Its purpose is to examine how fingerprints interact with surface texture to cause stress variations in tune with the sensitivities of Meissner and Pacinian corpuscles through which humans in part interpret tactile sensations. A two-dimensional multilayer elastic finite element model of a fingertip has been created for this purpose. Results show that fingertip’s epidermal ridges have little effect on stress distribution within the fingertip in static loading but significantly increase stress oscillations during sliding over a textured surface. Oscillation frequencies from the sliding simulations are in ranges that should stimulate a fingertip’s Meissner and Pacinian corpuscle nerve endings. 相似文献
149.
G. Xiong R. Shao S. J. Peppernick A. G. Joly K. M. Beck W. P. Hess M. Cai J. Duchene J. Y. Wang W. D. Wei 《JOM Journal of the Minerals, Metals and Materials Society》2010,62(12):90-93
Photoelectron emission microscopy (PEEM) is a versatile technique that can image a variety of materials including metals, semiconductors and even insulators. Under favorable conditions the most advanced aberration corrected instruments have a spatial resolution approaching 2 nm. Although PEEM cannot compete with transmission or scanning electron microscopies for ultimate resolution, the technique is much gentler and has the unique advantage of imaging structure as well as electronic and magnetic states on the nanoscale. Since the image contrast is derived from spatial variations in electron photoemission intensity, PEEM is ideal for interrogating both static and dynamic electronic properties of complex nanostructured materials. Here, we review the key principles and contrast mechanisms of PEEM and briefly summarize materials applications of PEEM. 相似文献
150.