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81.
This research project proposes the modeling of collective behaviors such as flocks, industrial districts, and markets. Unlike many other approaches, the aim is to identify ways to recognize, change, and maintain the coherence of collective behaviors, as well as inducing their emergence in configurations of elements that only interact without acquiring properties. The basic assumption is that currently collective behavior is not adequately modeled for the purpose described above when intended as given by sequences of states adopted by the same system over time. Here the sequence of states of a collective behavior in time is considered as corresponding to sequences of different states adopted by systems made up of the same elements interacting with different structures. Sequences of structures are considered to establish meta-structures and their properties correspond to the coherence acquired. The project is based on the use of mesoscopic variables to represent such structural dynamics considered in turn to represent the continuous emergence of coherent collective behavior. Mesoscopic variables are specified and their properties considered as meta-structural properties (properties of sequences of structures). The purpose of this research project is to search for meta-structural properties within processes of computational emergence (computer simulated). I discuss the problem of prescribing meta-structural properties to non-coherent, disordered collective behaviors. I introduce possible approaches for applications to social systems.  相似文献   
82.
For groups of persons with low or medium levels of education, Big Five personality scales typically yield scores that poorly replicate the idealized Big Five factor pattern. On the basis of representative samples of German adults, Rammstedt et al. have demonstrated that correcting each person's score for acquiescence eliminates this problem. In the present 18‐country study using large samples representative of each country's adult population, we found that, in all cases, correcting for acquiescence did indeed improve the congruence of factor loadings with an idealized Big Five pattern. However, although this correction led to acceptably high correspondence levels in all countries classified as individualistic, this was not always true for non‐individualistic countries. Possible reasons for this finding are discussed. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
83.
The U.S. Army developed the Global Assessment Tool (GAT) to monitor psychosocial fitness and well-being among soldiers and provide a means to objectively gauge the success of newly implemented resilience training programs. Despite its widespread use (taken over 5.2 million times) and stated utility for program evaluation, there is relatively little published evidence regarding the GAT’s reliability and validity. We used exploratory structural equation modeling (ESEM) with 4 random samples of soldiers (n = 10,000 each) to examine the factorial validity and reliability of the GAT. An 11-factor solution (Self-Management, Positive Affect, Meaning, Work Engagement, Organizational Trust, Loneliness, Negative Cognitions, Hostility, Negative Emotions, Depressive Symptoms, and Emotion-Focused Coping), with 4 additional factors assessing character strengths (Intellect, Warmth, Civic Strengths, and Temperance), fit well and replicated in a second random sample. A higher order, 2-factor model using composites scores and positing positive and negative psychosocial competencies also fit well. Tests of measurement invariance using a third random sample reinforced consistent measurement properties across gender, age, and rank, with the exception of character strengths, which produced different factor structures for males and females. Further validity tests using a fourth random sample underscored a modicum of divergence among the resilience factors and convergence among the character strengths factors. We conclude with recommendations for enhancing and refining the GAT and discuss the GAT’s utility as a reliable, multidimensional psychosocial assessment that can be used to evaluate the efficacy of military resilience training programs.  相似文献   
84.
Spearman's Law of Diminishing Returns (SLODR) is the idea that the structure of human cognitive ability is more differentiated and g a weaker determinant of cognitive performance at higher levels of ability. In this study, we distinguish between ‘traditional’ methods of testing SLODR and ‘contemporary’ methods of testing SLODR. It is the former set of methods from which the vast majority of the evidence base for SLODR derives. We demonstrated that it is easy to mimic SLODR and reverse SLODR effects in these traditional methods of assessing SLODR by using data with skewed observed variable distributions. The skewness magnitudes did not need to be large to produce these effects and they fell well within the range of values that are usually considered unproblematic for parametric statistic analysis. In simulated datasets, positive subtest skewness resulted in SLODR and negative subtest skewness resulted in reverse SLODR. In contemporary methods of testing SLODR, non-linear g-loadings or a skewed g are assumed to reflect evidence for SLODR. When we applied contemporary methods of testing SLODR to these data, there was evidence of heteroscedastic residuals but no evidence of non-linear g-loadings or skewed g distributions. We broadly replicated the effects of subtest skew from these simulated datasets in real data from the Minnesota Study of Twins Reared Apart. Results imply that traditional methods of assessing SLODR cannot distinguish between effects due to subtest characteristics that have nothing to do with differences in ability structure at different levels of g and true SLODR effects. This calls into question the empirical support for SLODR.  相似文献   
85.
赖寒  徐苗  宋宜颖  刘嘉 《心理学报》2013,45(5):491-507
本研究根据音乐加工的层级结构, 对现有的脑成像研究进行了元分析, 探讨了音乐知觉的神经基础。具体而言, 对特异于音乐知觉加工的两个层级, 音程分析和结构分析的神经基础进行了分析, 并在此基础上对比了参与两个层级加工的脑区。结果发现, 音程分析主要的激活分布在双侧颞上回和右侧额下回, 在中央前回、角回和脑岛等脑区也有分布。音程分析在颞上回激活最多, 可能表明颞上回为音程分析的核心区域。结构分析激活分布较广, 主要激活颞上回、颞横回和前额叶区域, 此外, 还激活了下顶叶、缘上回和舌回等顶枕区域。结构分析在前额叶激活最多, 可能表明前额叶为结构分析的核心区域。最后, 对比两层级激活的脑区发现, 二者仅在后侧颞上回存在着重合, 而在绝大部分脑区则表现出分离, 这暗示了音程分析和结构分析通过颞上回进行交流, 并负责音乐不同层面的加工。  相似文献   
86.
The present study provides evidence for the role of ferrite-grain-size distributions on the occurrence of void initiation in a low-carbon steel. Various thermomechanical treatments were undertaken to create ultrafine, bimodal and coarse distributions of ferrite grain sizes. A two-parameter characterisation of probable void initiation sites is proposed, namely an elastic modulus difference and a difference in Schmid factor of the grains surrounding the void. All microstructures were categorised based on the ability to facilitate or resist void nucleation. For coarse grains, the elastic modulus and the Schmid factor differences are the highest, while they are intermediate for ultrafine grains and the lowest for the bimodal microstructure.  相似文献   
87.
ABSTRACT

We present results for the structural, electronic, vibrational, and electron-phonon coupling properties of LaSn3 and CaSn3 adopting the simple cubic AuCu3-type structure obtained using the the generalised gradient approximation of the density functional theory and plane wave ab initio pseudopotential method. Our electronic results show that both materials display metallic character with several bands, which have mainly Sn 5p character, crossing the Fermi level. The calculated phonon spectrum of LaSn3 accords very well with reported experimental measurements. The weights of the peaks in the Eliashberg spectral function of both compounds are enhanced with the use of experimental lattice constant in our electron-phonon calculation, increasing the value of average electron phonon coupling parameter from 0.876 to 0.937 for LaSn3 (by 7%) and from 0.642 to 0.725 for CaSn3 (by 13%). The use of experimental lattice constant also improves the agreement between theoretical and experimental values of the superconducting temperature for both compounds.  相似文献   
88.

Grain-boundary diffusion in the regime affected by internal stresses of triple-line disclinations is analysed. The concentration profiles in a stressed solid averaged over a distribution of hydrostatic stress gradients are calculated. It is shown that the stresses from triple-line disclinations in as-prepared submicrocrystalline metals can significantly increase the effective grain-boundary diffusion coefficient, which is obtained by fitting the concentration profiles to the solution of a diffusion equation for an unstressed polycrystal.  相似文献   
89.
The structural validity of the Personal Globe Inventory (PGI, Tracey, 2002) as applied to a Caribbean sample of university students in Jamaica (N = 103) and Trinidad (N = 118) was examined. The fit of the data to Holland's six-type RIASEC, the PGI eight-type model, and the PGI spherical structure was examined using the randomized test of hypothesized order relations. The results demonstrated that the circular structure (i.e. RIASEC and the eight-type model), unlike the spherical structure, fits the Caribbean data well. No structural differences were found between gender and nationality. Further examination of the cultural perception of prestige in a Caribbean sample is warranted. Overall, the results support the structural validity of the PGI in Caribbean applications.  相似文献   
90.
This study explored the factor structure of the Proactive Coping Inventory (PCI) to determine whether its six-factor structure holds within the Southern African context. Data on proactive coping were collected from students attending three universities, one each in Botswana (n=88, females=45.5%, mean age=21.31 years, SD=2.04), Namibia (n=38, females=47.4%, mean age=24.21 years, SD=3.47) and South Africa (n=496, females=56.9%; mean age=22.27 years, SD=2.60). Exploratory factor analysis was used to determine the factor structure of the PCI. Findings suggest that the PCI is comprised of two factors: Future-Oriented Coping (comprised of Proactive Coping, Reflective Coping, Strategic Planning and Preventive Coping) and Support Seeking (comprised of Instrumental Support Seeking and Emotional Support Seeking). This is in line with theory that suggests that individuals cope by means of persisting towards goal attainment.  相似文献   
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