New insights on tensile plasticity of ultrafine-grained metallic materials

ABSTRACT

The tensile properties of TiNi_43.5Fe_6.5 alloy samples having different grain sizes (0.16, 0.35, 1.7, 2.3, and 3.9?μm) and fabricated by severe plastic deformation and annealing were investigated. It was observed that both the strength and the elongation of the alloy increase with a decrease in the grain size until the average size reaches 1.7?μm. However, for average grain sizes smaller than 1.7?μm, the elongation decreases continuously with further grain refinement. On the other hand, the strain-hardening rate does not decrease with the decrease in plasticity but instead increases slightly. The poor ductility of the ultrafine-grained TiNi_43.5Fe_6.5 alloy is accompanied by a high degree of strain hardening. This newly observed ductility behaviour of the ultrafine-grained TiNi_43.5Fe_6.5 alloy is elucidated by characterising the intragranular and grain boundaries.     

Experimental investigations of TB2 alloy by pack boriding with rare-earth oxides

ABSTRACT

An orthogonal test with four factors, namely temperature, time, type of rare-earth oxides (REOs) and REO content, was performed to obtain the optimised boriding parameters of TB2 alloy by pack boriding with REOs. It is found that temperature has the strongest effect on the boride layer thickness, while time has the strongest effect on the surface hardness and coefficient of friction. The optimum parameters for pack boriding of TB2 alloy with REO are a temperature of 1373?K, a time of 20?h, La₂O₃ as the REO with a content of 4?wt.%.     

不同参数分布形态下GIRM方法和传统GT方法的对比研究

GIRM(Generalizability in Item Response Modeling)是一种将概化理论GT和项目反应理论IRT相结合后计算概化理论中方差分量的一种方法.当GIRM方法下θp和βi的抽样分布与GIRM方法中的MCMC先验分布一致时,GIRM方法对方差分量估计具有较高的准确性.为了进一步检验GIRM方法对IRT参数分布形态的敏感性,研究在将MCMC先验分布固定的情况下,探讨不同IRT参数分布形态下GIRM方法的适用性,并将所得结果与传统GT方法相比较.结果表明:(1)在各种参数分布形态下,采用GIRM方法估计IRT模型的参数是可行的;(2)GIRM方法在被试能力参数为标准正态分布时对σ2(p)估计的准确性高于传统GT方法,但在均匀分布和偏态分布下略差于传统GT方法;(3) GIRM方法在题目难度参数为偏态分布情况下对σ2(i)的估计准确性显著差于传统GT方法;(4)两种方法对于σ2(pie)估计的准确性在任何参数分布形态下都大致相当,优劣并无统一规律.     

A Personal Synthesis of Social Construction and Phenomenology

In this essay, I narrate five short stories about how I have encountered and struggled with social construction and phenomenology, as well as my ongoing synthesis of the two perspectives.     

Effects of Image Preprocessing on Face Matching and Recognition in Human Observers

In person identification, recognition failure due to variations of illumination is common. In this study, we employed image‐processing techniques to tackle this problem. Participants performed recognition and matching tasks where the face stimuli were either original images or computer‐processed images in which shading was weakened via a number of image‐processing techniques. The results show that whereas recognition accuracy in a memory task was unaffected, some of the techniques significantly improved the identification performance in a face‐matching task. We conclude that relative to long‐term face memory, face matching is more susceptible to discrepancy of shading in different images of a face. Reducing the discrepancy by certain preprocessing techniques can facilitate person identification when original face images contain large illumination differences. Copyright © 2013 John Wiley & Sons, Ltd.     

Formal Mentoring in Military Academies

We examined the relationship between mentoring functions and protégé outcomes in formal mentoring relationships in military academies. A total of 424 (listed as 424 under Method) freshmen and 659 senior cadets from six different military academies participated in the survey. Results of hierarchical multiple regression analyses suggest that career mentoring was positively related to mentor satisfaction and participants' provision of career mentoring to their protégés. Surprisingly, career mentoring was negatively related to freshmen's commitment to a military career. We found that psychosocial mentoring was positively related to mentor satisfaction and participants' commitment to a military career, leadership competency, and provision of psychosocial mentoring to their protégés. Furthermore, psychological mentoring was negatively related to stress. We discuss these findings and their implications for mentoring research and practices in the military.     

Emotional facilitation effect in the picture–word interference task: An ERP study

In this paper, we aimed to verify the emotional facilitation effect in the picture–word interference task using event-related potentials. Twenty-one healthy subjects were asked to categorize the emotional valences of pictures accompanied by emotionally congruent, either centrally or laterally positioned Chinese words. For both the foveal and lateral word presentations, the reaction times were faster compared to the picture-only presentation. Compared to the picture-only presentation, P200 amplitude increased under the foveal word presentation condition and decreased under the lateral word presentation condition, indicating that more attentional resources were required when an accompanying word was in the center of a picture than when the word was in the lateral position. Latency of P300 was shorter in response to picture–word stimuli irrespective of word position, indicating that an emotionally congruent word facilitated the emotional processing of the target picture, which verified the emotional facilitation effect and was consistent with the results in psychology. The late positive component was more positive when the picture–word stimuli were more positive, which reflected the feature of positivity offset. The findings suggest that the time window for an emotional facilitation effect may be limited to processing aspects associated with P300 (i.e., affective evaluation).     

贝叶斯推理中的情感启发式

该研究通过事件性质、重要程度和主体相关性对贝叶斯推算、判断的影响,探索了贝叶斯推理中的情绪启发式现象,结果表明:1)在贝叶斯推算中,事件重要程度不同,后验概率值的事件性质的主效应显著性不同,事件性质与主体相关性交互作用的显著性不同,但主体相关性的主效应均为不显著;2)在贝叶斯判断中,事件重要程度不同,事件性质和主体相关性在判断上的效果不同;3)在贝叶斯推理中,情绪启发式致使个体的推断结果具有某种系统化的倾向.     

新疆察布查尔锡伯族宗教信仰历史与现状考察之一——锡伯族的藏传佛教信仰

锡伯族是发源于我国东北的古老民族之一,西迁伊犁后曾为祖国的屯垦戍边做出了卓越的贡献。本文以锡伯营藏传佛教寺院和卡伦寺庙为主要考察对象,用较翔实的资料论述了靖远寺的历史、建置、藏经主要的经济来源、宗教活动以及卡伦寺庙的相关情况,来表明藏传佛教在锡伯族社会中的功能,揭示其对锡伯族的影响。     

就美德伦理的现代意义与万俊人教授商榷——以麦金太尔美德伦理思想为中心

在《美德伦理的现代意义》一文中,万俊人教授认为麦金太尔的美德伦理是在现代性道德文化语境内部对现代性进行反思。这不仅在根本上误读了麦金太尔的思想,而且基于此种误读寻求的美德伦理的现代意义掩盖了美德伦理原本应该具有的重大现实意义。本文试图通过对万俊人教授文中的核心观点进行辨析,阐明麦金太尔的美德伦理是跳出现代性道德概念框架,站在整个西方道德文化传统的立场上对现代性进行反思,并以此为基础揭示美德伦理的现代意义:对现代性道德概念框架本身进行批判反思,并指出一种符合人类道德生活客观实际的道德探究方法,即美德伦理探究方法。