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51.
The grain size variation in a gradient surface produced by a punching and recovery process on a Cu-30Ni alloy has been observed by atomic force microscopy. The friction characteristics of the gradient surface in a 3.5 wt% NaCl solution were investigated using a micro-indenter probe, a pin-on-disc type tribometer, a strain sensor and an optical microscope. The results showed that the hardness and grain size can be well represented by the Hall–Petch relationship when the gain size is more than 30?nm. The wear rate, friction coefficient and adhesive force all increase depth below the surface. These variations are attributed to a gradual increasing grain size with depth. The morphologies of the worn track were also studied to understand further the corrosive wear behaviour of gradient surfaces. 相似文献
52.
Diana Ridgeway 《Memory (Hove, England)》2013,21(8):990-1000
Spatial short-term memory performance was examined in relation to participants’ strategies. A total of 20 adult participants viewed and reproduced sequences of locations that varied in length (five, six, seven, or eight locations) and spatial separability (a manipulation of the configurations). In trial-by-trial self-reports, participants described five types of strategies. Chunking the spatial sequences into groups of three or four locations was the sole strategy associated with increased accuracy. Participants demonstrated considerable variability in the strategies that they selected, suggesting that cognitive resources are allocated to strategy selection, execution, and monitoring in the spatial span task. Spatially separable sequences were more accurately recalled than nonseparable sequences, independent of strategic grouping, suggesting two levels of grouping in the spatial span task. 相似文献
53.
Abraham S. Luchins 《The Journal of psychology》2013,147(5):471-486
This paper traces the history of the American public asylum from the 1840s through the late 19th century. The focus is on social factors that contributed to the establishment of public institutions at the urging of reformers, the attempts to model them on the architecture and “moral treatment” offered by the best private institutions, the crowding of the asylums, the growing criticism aimed at the asylums and their superintendents, and the effects of calls for other approaches and for scientific management. Knowledge of the asylum's history may be useful today, as we stand at the crossroads in the treatment of the mentally ill. 相似文献
54.
Wei‐Bin Zhang 《World Futures: Journal of General Evolution》2013,69(4):209-223
The purpose of this study is to discuss the dynamic interdependence of knowledge and economic growth. We show that the traditional economics, which treats knowledge as parameters and is mainly developed within linearized, stable and static frameworks can hardly explain the modern economic complexity. We argue that it is necessary to treat creativity, learning and knowledge utilization as endogenous dynamic processes of social and economic evolution. To handle with the complicated dynamic interdependence of wealth and knowledge accumulation, we need to apply genuine nonlinear dynamic theory. In particular, we discuss possible benefits of government's intervention in education and science to the society when the social and economic evolution is characterized of nonlinearity, instability and multi‐equilibria. 相似文献
55.
This study investigated whether overgeneral autobiographical memory (OGM) predicts the course of symptoms of depression and anxiety in a community sample, after 5, 6, 12 and 18 months. Participants (N = 156) completed the Autobiographical Memory Test and the Depression Anxiety Stress Scales-21 (DASS-21) at baseline and were subsequently reassessed using the DASS-21 at four time points over a period of 18 months. Using latent growth curve modelling, we found that OGM was associated with a linear increase in depression. We were unable to detect changes over time in anxiety. OGM may be an important marker to identify people at risk for depression in the future, but more research is needed with anxiety. 相似文献
56.
Jonathan L. Helm Jonas G. Miller Sarah Kahle Natalie R. Troxel Paul D. Hastings 《Multivariate behavioral research》2013,48(4):521-543
Physiological synchrony within a dyad, or the degree of temporal correspondence between two individuals' physiological systems, has become a focal area of psychological research. Multiple methods have been used for measuring and modeling physiological synchrony. Each method extracts and analyzes different types of physiological synchrony, where ‘type’ refers to a specific manner through which two different physiological signals may correlate. Yet, to our knowledge, there is no documentation of the different methods, how each method corresponds to a specific type of synchrony, and the statistical assumptions embedded within each method. Hence, this article outlines several approaches for measuring and modeling physiological synchrony, connects each type of synchrony to a specific method, and identifies the assumptions that need to be satisfied for each method to appropriately extract each type of synchrony. Furthermore, this article demonstrates how to test for between-dyad differences of synchrony via inclusion of dyad-level (i.e., time-invariant) covariates. Finally, we complement each method with an empirical demonstration, as well as online supplemental material that contains Mplus code. 相似文献
57.
Both positive and negative changes are commonly reported by cancer survivors, and both may impact quality of life. Yet few studies have directly compared the associations of positive and negative changes across multiple life domains with multiple aspects of well-being. This study examined positive and negative changes and their conjoint relation to a range of well-being indices. We used correlational and regression analyses of data from 237 young to middle aged (X?=?45.3?years) cancer survivors, several years after treatment. Measures included demographic and medical variables, medical post-cancer positive and negative changes on multiple life domains, and a range of positive and negative adjustment indices. Demographic factors, especially income, related to both positive and negative outcomes. On average, participants reported no change on most life domains, although modest amounts of both positive and negative changes were reported. Negative change, rather than positive change, was closely associated with cancer survivors’ adjustment. Detailed measurement of both positive and negative changes – as well as lack of change – is important to advance understanding of cancer's impact on survivors. 相似文献
58.
Jackie L. Micklewright Tricia Z. King Robin D. Morris Mary K. Morris 《Child neuropsychology》2013,19(6):522-527
The Rey Auditory Verbal Learning Test was utilized to examine attention, learning, and memory abilities in 42 children with cerebellar (N?=?18) and third ventricle tumors (N?=?24). Children with cerebellar tumors exhibited significant auditory attentional impairments and displayed adequate encoding and retrieval across subsequent learning and memory trials. In contrast, children with third ventricle tumors exhibited average auditory attentional abilities, but they displayed mild encoding deficits across trials 2–5. Furthermore, the third ventricle group's compromised performance on the delayed recall trial and average performance on the delayed recognition trial is suggestive of underlying retrieval deficits. 相似文献
59.
Liangyun Lan Xiangwei Kong Zhiyong Hu Chunlin Qiu 《Philosophical Magazine Letters》2013,93(12):764-771
The Y-groove cracking test by submerged arc welding was employed to study the susceptibility of a low-carbon high-strength steel to hydrogen-induced cold cracking (HICC). The morphology of hydrogen cracks was observed using an electron probe microscope. The results showed that the heat-affected zone (HAZ) has a higher susceptibility to HICC than the weld metal and that increasing heat input can improve the HICC resistance of the weldment. The intergranular microcracking is the main HICC mode at the lowest heat input condition, accompanied with some transgranular microcracks attached to complex inclusions. In combination with phase transformation behaviour in sub-zones, the effect of the phase transformation sequence is proposed to try to illustrate the fact that the fine-grained HAZ has higher probability of hydrogen cracking than the coarse-grained HAZ owing to the occurrence of hydrogen enrichment in the fine-grained HAZ after the transformation. 相似文献
60.
Luigi Cannavacciuolo 《Philosophical Magazine Letters》2013,93(12):527-535
ABSTRACTThe fundamental origin of the reversal transition during crystal growth has been investigated by Monte Carlo simulations. Evidence is provided supporting the geometrical nature of the transition, arising from the broken translational invariance at the growth front and the interactions of multipoles of opposed parity. The range of interactions, the details of the force field and model are irrelevant to the occurrence and only determine the functional behaviour of the relevant physical quantities like the localisation of the critical point and the morphology of the phase diagram. 相似文献