Lexical characteristics of words used in emotional Stroop experiments.

Validity of the emotional Stroop task hinges on equivalence between the emotion and the control words in terms of lexical features related to word recognition. The authors evaluated the lexical features of 1,033 words used in 32 published emotional Stroop studies. Emotion words were significantly lower in frequency of use, longer in length, and had smaller orthographic neighborhoods than words used as controls. These lexical features contribute to slower word recognition and hence are likely to contribute to delayed latencies in color naming. The often-replicated slowdown in color naming of emotion words may be due, in part, to lexical differences between the emotion and control words used in the majority of such studies to date. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Analysis of a mode III crack problem in a functionally graded coating-substrate system with finite thickness

This paper presents an analysis of the static problem of model III crack of a functionally graded coating-substrate system with an internal crack perpendicular to the interface under antiplane shear loading when the coating layer and substrate have finite thickness. After the Fourier transform method is employed, the expressions of the displacement components can be obtained. Integral transforms are employed to reduce the problem to a singular integral equation that can be solved numerically. The influences of the nonhomogeneity constant, relative crack length and thickness ratio are quantitatively studied.     

Design of Computer Experiments for Metamodel Generation

We review the use of statistical design and analysis of computer experiments (DACE) for the generation of parsimonious, surrogate models, also known as metamodels. Such metamodels are used to replace cpu- or memory-intensive, discretized approximations that often arise in MEMS and MOEMS. Emphasis is placed on optimal designs.     

Anti-plane transient fracture analysis of the functionally gradient elastic bi-material weak/infinitesimal-discontinuous interface

The mechanical model was established for the Dirac-type anti-plane transient fracture problem of the weak-discontinuous interface between two FGMs half-planes. Integral transform was adopted to derive Cauchy singular integral equation and Erdogan’s allocation method was used to calculate transient stress intensity factors numerically. The numerical solutions of the weak-discontinuous case were contrasted with those of the infinitesimal-discontinuous one. Two possible effective methods to diminish the peak values of transient stress intensity factors are discussed. One is to reduce the weak-discontinuity of the interface, i.e., to make the ratio of the two non-homogeneity parameters be close to 1.0 and to avoid the case that the signs of the two non-homogeneity parameters are different. Another is to make a compromise between the weak-discontinuity and the all-continuity, i.e., to make FGMs interface infinitesimal-discontinuous. Simple method was suggested for the realization of the infinitesimal-discontinuity of FGMs interface. From the strong-discontinuous interface to the weak- discontinuous one, and then to the infinitesimal-discontinuous one, this is a law and trend of the development of composite interfaces. To design and manufacture infinitesimal-discontinuous interfaces may be a brand-new effective approach to enhance the reliability of composite structures, and the first rank infinitesimal-discontinuity is enough to improve the mechanical performances of composites notably.     

A simplified method for predicting the stress concentration in notches from experimental stress data

This paper describes a simple procedure to obtain very reliable estimates of the stress concentration at the root of a notch using only data from points beneath the notch root along its axis of symmetry. The advantages of the method are (i) data from only a few points are needed, (ii) the necessary computations require only a hand held calculator, (iii) inaccurate data becomes quite apparent to the analyst, and (iv) random experimental errors are largely compensated.     

Estimating the error of an effect in unreplicated 2-level fractional factorial designs

Saturated fractional factorial experimental designs and orthogonal main effect plans are extremely valuable tools in quality engineering. However, one problem with these designs is that there are no replicate runs to be used for estimating experimental error. This note develops an estimator of the experimental error based on the hypothesis that not all factor effects will be non-zero. A joint Bayesian prior distribution is presented for the experimental error variance of an effect, σ², and the probability that each effect is non-zero. From this prior distribution a posterior marginal distribution for σ² is derived along with a direct estimate of σ². This method is compared with the traditional methods of estimating σ² in unreplicated designs through a numerical example.     

Reliability improvement via taguchi's robust design

Taguchi's robust design strategy, whose aim is to make processes and products insensitive to factors which are hard or impossible to control (termed noise factors), is an important paradigm for improving products and processes. We present an overview of the strategy and tactics for robust design and demonstrate its usefulness for reliability improvement. Two important components of robust design are a criterion for assessing the effect of the noise factors and experimentation according to specialized experimental plans. Recent criticism of Taguchi's criterion and his analysis of its estimates has led to an alternative approach of modelling the response directly. We give additional reasons for using this response-model approach in the context of reliability improvement. Using the model for the response, appropriate criteria for assessing the effect of the noise factors can then be evaluated. We consider an actual experiment and reanalyse its data to illustrate these ideas and method.     

Developments in a least squares asymptotic analysis of isochromatic data from stress concentration regions in plane problems

A complete separation of stresses throughout the entire stress concentration region near notches in plane, isotropic, linearly elastic plates is achieved using only isochromatic (difference of principal stresses) data. These data, which are obtained easily by conventional photoelastic techniques, are analysed by a non-linear least squares technique based upon previously derived equations describing the asymptotic character of the rapidly varying stress field near the root of the notch. This paper demonstrates that isochromatic data of typical experimental accuracy from relatively few, arbitrarily located data points within the highly stressed region is sufficient to accurately predict the entire stress field, including location and magnitude of critical stress(es).     

时效对Al-Li(2091)合金应力腐蚀行为的影响

本文研究了在不同时效状态下Al-Li(2091)合金在3％NaCl+0.5％H_2O_2溶液中应力腐蚀行为;并与传统的2024(CZ)合金进行了比较。结果表明,2091合金具有较好的抗应力腐蚀能力。利用扫描电镜与透射电镜分别对应力腐蚀断口和合金显微组织进行了观察和分析;对应力腐蚀开裂的机制进行了初步探讨。     

The stress and displacement fields at the tip of crazes in glassy polymers

This analysis models a craze region in glassy polymers as an elastic transversely isotropic homogeneous inclusion of thin elliptical shape with different elastic properties from the bulk polymer. The plane elasticity problem for an applied uniform stress field is solved and the results dimensionalized with respect to the craze tip radius. Stress and strain enhancements of several times far field values are found to occur at the craze tip and are independent of craze tip radius. These results are consistent with experimentally observed characteristics of craze growth and should be important in assessing the relative merits of different criteria that have been proposed for craze growth in glassy polymers.