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581.
The nature of shear flow lines in equal-channel angular-pressed (ECAPed) metals has been investigated experimentally and theoretically. Experimental results indicate that, for metals pressed in a right-angle die, the shear flow lines often have an angle of ~27° with respect to the extrusion direction. It is suggested that the shear flow lines are composed of a group of elongated grains with an elongation direction that deviates slightly from that of the shear flow lines.  相似文献   
582.

The mechanical behaviour of bulk ultrafine-grained Al-7.5 wt% Mg alloy consolidated from cryomilled powders has been investigated. The experimental data show that the alloy exhibits high strength, low strain hardening, serrated flow and relatively high ductility. In addition, the data indicate that the yield strength in tension is essentially equal to that in compression. The yield and flow strengths of the alloy are discussed in terms of strengthening processes that are related to grain size, the Orowan mechanism and solid-solution hardening. The serrations in the stress-strain curve are discussed in terms of dynamic strain ageing and deformation twinning.  相似文献   
583.
The surface tension of undercooled liquid cobalt has been measured by the oscillating-drop technique combined with electromagnetic levitation. The accuracy of the method was verified by measurements of the surface tension of liquid nickel. The liquid cobalt was undercooled by up to 231K (0.13T m), and its surface tension determined to be σCo =1875 0.348(T-T m)mNm-1. From this result, the viscosity, self-diffusion coefficient, density and thermal diffusivity of undercooled liquid cobalt were derived. Using these thermophysical parameters, the growth velocity of cobalt dendrite is calculated and shown to agree well with experimental results. Furthermore, the Marangoni number and the Rayleigh number are calculated; these increase slowly with increasing degree of undercooling.  相似文献   
584.
韩迎春  莫雷 《心理科学》2013,36(1):20-26
采用自控速度的移动窗口技术,在3个实验中分别考察句法歧义消解的基本过程。阅读材料为 不含有词汇歧义的较为单纯的英语句法歧义句。结果为:实验1的研究结果表明在语料中不存 在歧义激发点的情况下,被试不会启动歧义的消解过程;实验2的研究结果表明当歧义激发点 与解歧区重合时,人们会选用再分析机制来处理解歧区语料;实验3的研究结果表明当歧义激 发点与歧义区重合时,人们会选用竞争机制来处理歧义区语料。本研究初步验证了基于激发点 的权变模型关于句法歧义消解过程的相关设想。  相似文献   
585.
A generalized linear modeling framework to the analysis of responses and response times is outlined. In this framework, referred to as bivariate generalized linear item response theory (B-GLIRT), separate generalized linear measurement models are specified for the responses and the response times that are subsequently linked by cross-relations. The cross-relations can take various forms. Here, we focus on cross-relations with a linear or interaction term for ability tests, and cross-relations with a curvilinear term for personality tests. In addition, we discuss how popular existing models from the psychometric literature are special cases in the B-GLIRT framework depending on restrictions in the cross-relation. This allows us to compare existing models conceptually and empirically. We discuss various extensions of the traditional models motivated by practical problems. We also illustrate the applicability of our approach using various real data examples, including data on personality and cognitive ability.  相似文献   
586.
587.
Although studies on the association between social capital and subjective well-being have been recently increasing many issues still remain unsolved. The purpose of this study is to investigate the association between various social capital dimensions both at the individual (political participation, network source, trust, and organizational participation) and area level (voting rate, trust, and organizational participation) and subjective well-being (happiness) using multilevel analysis while controlling for various control variables at multiple levels. Survey data was collected from December, 2010 to April, 2011 in Seoul, South Korea. The final sample was comprised of 4,585 respondents within all 25 administrative areas in Seoul. Results from the multilevel analysis revealed that all individual and area level (trust) social capital variables are positively associated with subjective happiness. Our findings also point to the need for more sophisticated studies with longitudinal datasets based on multilevel framework using instrumental variable analysis to clarify our knowledge regarding the effects of social capital on subjective well-being.  相似文献   
588.
货币幻觉是指经济交易活动中,人们因倾向于以货币的名义价值而非实际价值思考从而对其消费和投资行为造成影响的一种认知偏差。本研究探讨了在通货膨胀和通货紧缩下以及产品类型对货币幻觉程度的影响。研究发现,在通货膨胀或通货紧缩下,大部分被试判断经济状况时不受货币名义价值的影响,而判断快乐程度和离职意向时受到货币名义价值的影响;在相同的涨价幅度下被试对日常消费品和昂贵消费品涨价幅度的判断差异显著,昂贵消费品引起人们更高程度的货币幻觉。  相似文献   
589.
Abstract

This article introduces the Attitudinal Entropy (AE) framework, which builds on the Causal Attitude Network model that conceptualizes attitudes as Ising networks. The AE framework rests on three propositions. First, attitude inconsistency and instability are two related indications of attitudinal entropy, a measure of randomness derived from thermodynamics. Second, energy of attitude configurations serves as a local processing strategy to reduce the global entropy of attitude networks. Third, directing attention to and thinking about attitude objects reduces attitudinal entropy. We first discuss several determinants of attitudinal entropy reduction and show that several findings in the attitude literature, such as the mere thought effect on attitude polarization and the effects of heuristic versus systematic processing of arguments, follow from the AE framework. Second, we discuss the AE framework’s implications for ambivalence and cognitive dissonance.  相似文献   
590.
We show how the hierarchical model for responses and response times as developed by van der Linden (2007), Fox, Klein Entink, and van der Linden (2007), Klein Entink, Fox, and van der Linden (2009), and Glas and van der Linden (2010) can be simplified to a generalized linear factor model with only the mild restriction that there is no hierarchical model at the item side. This result is valuable as it enables all well‐developed modelling tools and extensions that come with these methods. We show that the restriction we impose on the hierarchical model does not influence parameter recovery under realistic circumstances. In addition, we present two illustrative real data analyses to demonstrate the practical benefits of our approach.  相似文献   
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