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51.
A.G. Gurgel W.F. Sales C.S. de Barcellos J. Bonney E.O. Ezugwu 《International Journal of Machine Tools and Manufacture》2006,46(12-13):1637-1642
The main objective of this study is to implement a parameter sensitivity analysis method to be used in the search of optimal machining conditions with respect to surface quality. Presently, the element-free Galerkin (EFGM) approximating functions are used to evaluate the properties of machined surfaces with cutting parameters when turning AISI 4140 steel using arbitrary sets of experimental values and the EFGM approximation functions, based on the moving least-squares method, in order to obtain the sensitivities through proper local derivations. This method shows the sensitivity of each surface parameter for each input variable. The variables investigated were cutting speed (vc), depth of cut (ap), feed rate (f) and the surface roughness (Ra). The sensitivity results showed that the feed rate has the highest influence on surface roughness when turning AISI 4140 steel followed by cutting speed and depth of cut. 相似文献
52.
Barrett Lisa Feldman; Quigley Karen S.; Bliss-Moreau Eliza; Aronson Keith R. 《Canadian Metallurgical Quarterly》2004,87(5):684
People differ in the extent to which they emphasize feelings of activation or deactivation in their verbal reports of experienced emotion, termed arousal focus (AF). Two multimethod studies indicate that AF is linked to heightened interoceptive sensitivity (as measured by performance on a heartbeat detection task). People who were more sensitive to their heartbeats emphasized feelings of activation and deactivation when reporting their experiences of emotion over time more than did those who were less sensitive. This relationship was not accounted for by several other variables, including simple language effects. Implications for the role of interoception in experienced emotion and the validity of self-reported emotion are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
53.
压阻式硅微加速度传感器的结构设计与仿真 总被引:1,自引:0,他引:1
一般的压阻式硅微加速度传感器结构多采用单梁加质量块的形式,这种形式的传感器灵敏度比较高,但它的横向效应较难克服,文中提出一种四梁结构的加速度传感器,通过仿真计算,说明该结构的加速度传感器具有良好的综合特性. 相似文献
54.
在气敏温度区域内研究了α-Fe_2O_3(SO_4~(2-),Sn)材料的电阻-温度特性,认为表面结构的变化导致温度特性出现峰值并呈现气敏性。可利用空气中电阻温度特性提供的信息改性或发现新的气敏材料。 相似文献
55.
Panagiotis Michaleris Daniel A. Tortorelli Creto A. Vidal 《International journal for numerical methods in engineering》1995,38(8):1259-1285
A systematic approach for the design of weakly coupled thermoelastoplastic systems is presented. The Newton–Raphson iteration method is used in the solution process so that analytic design sensitivity formulations may be efficiently derived via the direct differentiation technique. The derived formulations are suitable for finite element implementations. Analysis and sensitivity analysis capabilities are combined with numerical optimization to form an optimum design algorithm. To demonstrate the algorithm, we optimally design a weldment with respect to manufacturing and service life aspects. 相似文献
56.
57.
本文基于弹塑性分叉理论研究单向纤维增强复合材料的压缩破坏模式和压缩强度对缺陷的敏感性问题。对于常见复合材料,所得结论是:无缺陷或者小缺陷情况的破坏模式为倾斜破坏带;大缺陷情况的破坏模式为水平破坏带;形成水平破坏带的压力值小于形成倾斜破坏带的压力。 相似文献
58.
Multiple forms of a symbol-digit substitution task were used to provide a componential analysis of age differences in coding task performance. The results demonstrated age differences in feature encoding, memory, and visual search. A 2nd experiment was conducted with young adults to investigate a sensory deficit as a locus of age differences. The spatial contrast sensitivity deficit of older adults was simulated on forms by applying a digital filter. Persons in the age-simulated contrast condition performed worse than those in the normal contrast condition. The stimulus degradation effect was linked to visual search speed. The study illustrates the utility of componential analysis and offers direct support for the hypothesis that sensory deficits affect performance on tasks used to assess intelligence (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
59.
Rafael Gallego Lucia Comino Alberto Ruiz‐Cabello 《International journal for numerical methods in engineering》2006,66(12):1913-1933
In this paper, the material constant sensitivity boundary integral equation is presented, and its numerical solution proposed, based on boundary element techniques. The formulation deals with plane problems with general rectilinear anisotropy. Expressions for the computation of sensitivities for displacements, tractions, strains and stresses are derived, both for boundary and interior points. The sensitivities can be computed with respect to the bulk material properties or to the properties of part of the domain (inclusions, coatings, etc.). To assess the accuracy of the proposed approach, the computed results are compared to analytical ones derived from exact solutions obtained by complex potential theory, when possible, or finite difference derivatives otherwise. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
60.