ABSTRACT
Quenched residual stress in pentagon-curved forgings (PCGs) often leads to severe deformation during subsequent machining operations. This study aims to mitigate the quenched residual stress in PCGs through the implementation of the bulging method. The edge distance ratio (e/D), a geometric characteristic of PCGs, is defined and considered in the established thermo-mechanical model, which incorporates the effects of quenched residual stress. Increasing e/D resulted in amplified maximum internal stresses and surface stresses. To address this issue, a bulging finite element (FE) model was developed to effectively alleviate the quenched residual stress. The stress reduction in surface stress and internal stress was qualified using average stress reduction (Ra) and peak stress reduction (Rp), respectively. Notably, stress reduction exhibited an inverse relationship with e/D, indicating that decreasing e/D yields greater stress reduction. Furthermore, an overall stress reduction assessment was conducted for different bulging ratios, revealing that the stress reduction increased as the bulging ratio increased. A comprehensive comparison of different bulging ratios highlighted 2% as the most optimal bulging ratio for stress reduction in PCGs. X-ray diffraction measurement and the contour method were employed to determine surface stress and internal stress, respectively. The experimental results were in agreement with the simulation outcomes, validating the high accuracy of the FE model.
ABSTRACT
Some cognitive linguists (Rosch et al. Cognit Psychol 8:382-439, 1976; Ungerer and Schmid An introduction to cognitive linguistics, Pearson Education Limited, London, England, 2006) believe the basic level category has cognitive economy because the basic level category allows obtaining the maximum amount of information about an item with the lowest cognitive effort. Whether it is also true for L2 learners has not been verified so far. This study examined whether Chinese English learners' cognitive load of basic level category is lower than that of superordinate category and subordinate category. The eye movement data, including that of total duration of fixations, total number of fixations, duration of first fixation, and average duration of fixations, generated by 31 Chinese English learners while reading sentences with different levels of category words, were collected and analyzed. The results showed that Chinese English learners' cognitive load of the basic level category was the lowest. This study provides cross-linguistic experimental evidence for the basic level category theory, and also shows the cognitive economy of basic level categories is an intrinsic psychological property, no matter whether it is the first language or the second language that the readers use.
Subject(s)
Language , Linguistics , Humans , Reading , Educational Status , CognitionABSTRACT
This study used an eye-tracking method to examine whether Chinese translation equivalents activated by English prime words can continue to activate their Chinese homophones. With 30 English prime words, and 60 Chinese target words as materials, the experiment used a Tobii eye-tracking device to collect data from 30 university students while completing an English-Chinese lexical semantic-judgment task, aimed at investigating whether (1) when Chinese English learners see the English words, they can activate the homophones of Chinese translation equivalents; and (2) there is a word frequency effect in cross-language lexical activation, i.e., Chinese translation equivalents with different word frequencies have different effects on the activation speed. Compared with low-frequency Chinese translation equivalents, high-frequency Chinese equivalents can facilitate the activation faster and easier. The two research hypotheses were confirmed on several eye movement indicators, supporting the cross-language lexical activation as well as word-frequency effect of Chinese translation equivalents. This is also the first verification of cross-language dual-link lexical activation which engage both semantics and phonology, indicating that L2-L1 semantic activation has strong stability for further phonological activation.
