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1.
曹建军  顾荣宝 《黄金》2011,32(3):5-7
运用多重分形消除趋势波动分析(MF-DFA)方法对上海黄金市场和伦敦黄金市场日收益率数据进行实证研究.分析结果表明:两个黄金市场均表现出多重分形特征,其中上海黄金市场的多重分形特征更为显著,风险性也相对较大.该分析结果为更好地认识和研究黄金市场的复杂结构,提供了新的思路.  相似文献   

2.
应用Ising模型和平均场理论构造符合股市收益率的动力系统,借助于计算机软件Matlab,利用蒙特卡洛模拟方法,通过调整参数模拟得出动力系统的收益率序列.分析发现:Ising动力系统构造的收益率同证券市场股票指数波动率一样具有厚尾等统计特征.对模拟收益率原序列和混洗后的序列进行多重分形分析,得出了模拟收益率序列存在分布多重分形和相关性多重分形的结论.  相似文献   

3.
李秀  程翠花 《河北冶金》2014,(12):11-14
研究了不同MgO含量下烧结矿表观形貌的冶金性能与多重分形参数之间的对应关系.结果表明:多重分形可用于烧结矿的定量表征;Δα值的大小反映了整个分形结构上概率测度即磁铁矿分布的集中性和均匀性;f(α)max的值反映分形结构上概率测度即磁铁矿数量的多少.  相似文献   

4.
通过烧结杯试验制备了不同碱度的低硅烧结矿样品。利用SEM(扫描电子显微镜)对样品的表面形貌进行了表征。利用多重分形软件计算不同碱度烧结矿的多重分形谱。随着碱度提高,多重分形谱的宽度增加,烧结矿的表面形貌变得更加复杂,与SEM图像一致;多重分形谱最大和最小概率子集维数的差别减小,并且由正值变为负值,烧结矿孔隙由以宏观孔隙为主变为以微观孔隙为主,孔隙率提高。多重分形谱的计算结果定量地表征了烧结矿孔隙的分布形态,与扫描电镜图像结果一致。  相似文献   

5.
 利用压汞仪测定了不同碱度的低硅烧结矿样品的孔径分布。采用多重分形理论计算其孔径分布的分形特征,并结合冶金性能分析探讨了三者之间的关系。研究结果表明,随着碱度的增加,低硅烧结矿的孔径分布经历了一个从不均匀到均匀的变化过程。碱度为2.0时,其谱宽Δα最小,多重分形结构较均匀,分形特征较好。此时孔径分布较均匀,气孔较大,有利于冶金性能的改善。测定样品冶金性能的结果表明,当碱度为2.0时,其综合性能最好。  相似文献   

6.
为有效识别视频情感的内容,基于未确知数学理论,建立了视频低层特征和高层认知情感之间的联系,提出了一种基于未确知测度的新算法.首先,选取能反映情感变化的场景亮度、镜头切变率和色调效能作为视频情感低层特征,介绍了每种情感特征的数据提取方法,并由此构建了视频情感特征向量.其次,构造了视频场景的未确知对象空间和指标空间,并给出了量化用的场景亮度、镜头切变率和色调效能未确知测度函数,建立了未确知测度矩阵.最后,采用信息熵确定3个情感特征的权值,用置信度识别准则对视频场景的情感类型进行判定.实验结果验证了该方法的可行性和有效性.  相似文献   

7.
利用压汞仪测定了不同MgO条件下的低硅烧结矿样品的孔隙分布,结合多重分形理论计算了其孔隙分布的分形特征.研究结果表明,随着MgO含量的增加,烧结矿样品水银浸人增量与孔径尺寸之间的关系满足多重分形理论,当MgO含量为2.6%时,孔隙具有较好的分形结构,气孔尺度分布较均匀,气孔大,气孔率较好,有利于冶金性能的改善.适量的MgO含量可以提高低硅烧结矿的冶金性能,改善炉渣的稳定性、流动性,有利于高炉顺行.  相似文献   

8.
李立新  黄英钢  张葵  吕肖元  李彬  吴晓冬 《钢铁》2015,50(4):95-101
 轧辊表面形貌直接影响板带钢产品的表面质量甚至其织构组成。为了定量研究轧辊磨损过程中其表面形貌特征的变化规律,采集了1个磨辊周期内不同轧制阶段的轧辊表面图像信息,基于MATLAB平台,利用图像处理方法对不同阶段的下机轧辊表面图像进行了预处理,提取样本图像的几何形状及纹理特征等17维图像特征参数和分形维数,经过对这些参数的属性约简建立了用于轧辊磨损形貌状态识别的BP神经网络模型。结果表明:等效面积圆半径﹑圆形度﹑纹理熵及二阶矩等轧辊形貌图像特征参数和分形维数可以作为描述轧辊表面形貌的定量指标,并可用BP网络模型对轧辊磨损形貌进行识别预测。为建立轧辊磨损形貌的定量评价体系提供了新途径。  相似文献   

9.
采用图像分析方法研究铝用石墨质阴极在不同焙烧温度下孔隙结构特征及其演变,考察孔隙率、孔径分布、形状因子、视孔隙比表面积、连通性等参数的变化规律和孔隙复杂度的分形特征.结果表明:随着焙烧温度增加,孔隙率逐渐增大,而视孔隙比表面积、形状因子和连通性呈先减小后增大趋势;石墨质阴极试样不同温度下焙烧生成孔隙均符合分形规律,借助图像分析孔隙结构参数和分形维数可界定不同典型焙烧温度下阴极孔隙结构的演变特征,并据此提出相应的孔隙特征演化模式.   相似文献   

10.
袁潇 《南方金属》2015,(2):22-26
应用多重分形理论含量-数目(C-N)模型,对新疆巴勒尕矿区8种元素进行了地球化学异常分析.根据分形特征总结了三类多重分形模式,其中模式II反映了该模式在模式I的基础上叠加了高含量的异常场,形成了局部富集,具有很大的成矿潜力,具有模式II的元素为Pb、Zn.通过C-N多重分形模型求得的异常下限值,并结合地质特征分析,优选出3块靶区,为找矿预测提供了依据.  相似文献   

11.
Although multiple neuroimaging studies suggest that affect labeling (i.e., putting feelings into words) can dampen affect-related responses in the amygdala, the consequences of affect labeling have not been examined in other channels of emotional responding. We conducted four studies examining the effect of affect labeling on self-reported emotional experience. In study one, self-reported distress was lower during affect labeling, compared to passive watching, of negative emotional pictures. Studies two and three added reappraisal and distraction conditions, respectively. Affect labeling showed similar effects on self-reported distress as both of these intentional emotion regulation strategies. In each of the first three studies, however, participant predictions about the effects of affect labeling suggest that unlike reappraisal and distraction, people do not believe affect labeling to be an effective emotion regulation strategy. Even after having the experience of affect labels leading to lower distress, participants still predicted that affect labeling would increase distress in the future. Thus, affect labeling is best described as an incidental emotion regulation process. Finally, study four employed positive emotional pictures and here, affect labeling was associated with diminished self-reported pleasure, relative to passive watching. This suggests that affect labeling tends to dampen affective responses in general, rather than specifically alleviating negative affect. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   

12.
Emotion regulation includes multiple strategies that rely on different underlying abilities and that may be affected differently by aging. We assessed young, middle-aged, and older adults’ ability to implement 3 emotion regulation strategies (detached reappraisal, positive reappraisal, and behavior suppression) in a laboratory setting, using standardized emotional stimuli and a multimethod approach to assessing regulation success. Results revealed age-related decline in ability to implement detached reappraisal, enhancement of ability to implement positive reappraisal, and maintenance of ability to implement behavior suppression. We discuss these findings in terms of their implications for emotion theory and for promoting successful aging. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

13.
The relation between emotion and rationality is assessed by reviewing empirical findings from multiple disciplines. Two types of emotional phenomena are examined--incidental emotional states and integral emotional responses--and three conceptions of rationality are considered--logical, material, and ecological. Emotional states influence reasoning processes, are often misattributed to focal objects, distort beliefs in an assimilative fashion, disrupt self-control when intensely negative, but do not necessarily increase risk-taking. Integral emotional responses are often used as proxies for values, and valuations based on these responses exhibit distinct properties: efficiency, consistency, polarization, myopia, scale-insensitivity, and reference-dependence. Emotions seem to promote social and moral behavior. Conjectures about the design features of the affective system that give rise to seeming sources of rationality or irrationality are proposed. It is concluded that any categorical statement about the overall rationality or irrationality of emotion would be misleading. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   

14.
To study how perceptual asymmetries in the recognition of emotion reflect developmental changes in processing affective information, a fused rhyming dichotic word test with positive, negative, and neutral stimuli was administered to adults and children. Results suggested that the hemisphere in which affective information is initially processed affects the strength of perceptual asymmetry and that children's perceptual processing of emotional information is constrained by limited computational resources. Another experiment ruled out effects of volitional shifting of attention to emotional stimuli. These data further confirm that emotional processing involves integration of neural systems across brain regions, including distributed systems that support arousal and recognition. General developmental factors, such as processing capacity, contribute to the coordination of multiple systems responsible for processing emotional information. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

15.
Emotional and motivational dysfunction is fundamental to schizophrenia, and yet, the nature and scope of associated deficits are not well understood. This study assessed the integrity of emotional responding from the perspective of its underlying motivational systems during different phases of schizophrenia. Evaluative, somatic, and autonomic responses were measured during viewing of pictures categorized by emotional content, including threat, mutilation, contamination, illness, pollution, mild erotica, families, food, and nature. Participants were 13 patients at ultra high risk or prodromal for psychosis, 40 first-episode schizophrenia patients, 37 chronic schizophrenia patients, and 74 healthy comparison subjects. Irrespective of phase of illness, schizophrenia patients showed a robust and normal pattern of response across multiple systems, with differential engagement of the defensive and appetitive systems as a function of the motivational significance assigned to specific emotional contexts. Although the integrity of core motivational states also appeared to be intact in prodromal patients, a less consistent pattern of response was observed. As continuing efforts are made to identify emotional and motivational abnormalities in schizophrenia, identified deficits will likely be independent of a fundamental dysfunction in basic emotion and motivation response systems and involve integration with higher order processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

16.
Recent evidence suggests that emotional well-being improves from early adulthood to old age. This study used experience-sampling to examine the developmental course of emotional experience in a representative sample of adults spanning early to very late adulthood. Participants (N = 184, Wave 1; N = 191, Wave 2; N = 178, Wave 3) reported their emotional states at five randomly selected times each day for a one week period. Using a measurement burst design, the one-week sampling procedure was repeated five and then ten years later. Cross-sectional and growth curve analyses indicate that aging is associated with more positive overall emotional well-being, with greater emotional stability and with more complexity (as evidenced by greater co-occurrence of positive and negative emotions). These findings remained robust after accounting for other variables that may be related to emotional experience (personality, verbal fluency, physical health, and demographic variables). Finally, emotional experience predicted mortality; controlling for age, sex, and ethnicity, individuals who experienced relatively more positive than negative emotions in everyday life were more likely to have survived over a 13 year period. Findings are discussed in the theoretical context of socioemotional selectivity theory. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   

17.
The current study examined the relations between two aspects of emotional competence--emotion knowledge and emotion expression, and children's attentional competence during one school year. Participants were 263 first- and second-grade students at two rural elementary schools. A multiple regression analysis showed that emotion knowledge predicted attentional competence while controlling for age, gender, verbal ability, and initial levels of attentional competence. Multiple regression analyses examining predictors of peer nominations of emotion expression showed that attentional competence predicted peer nominations of happiness, sadness, and anger expression, and emotion knowledge predicted peer nominations of anger expression. Potential improvements for prevention programs and the importance of the findings for school personnel are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   

18.
Attentional deployment is a primary strategy individuals use to regulate emotion. In 2 experiments, a measure of an individual’s ability to deploy attention toward and away from emotional mental representations was developed. This measure of attentional control capacity for emotion adapted an explicit-cuing task switching paradigm in which participants had to shift between emotional and neutral mental sets. Experiment 1 (N = 118) showed that those higher in trait anxiety and worrisome thoughts took longer to switch from a neutral to an emotional mental set. In Experiment 2 (N = 42), participants were given a stressful anagram task, and those who switched more efficiently from a neutral set to an emotional set were more frustrated by the stressful task. In addition, those who switched more efficiently from an emotional set to a neutral set persisted longer on the stressful task. These findings provide an initial step toward identifying possible mechanisms through which individuals apply attentional control to emotional mental representations to regulate emotion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

19.
In a series of experiments, it was found that emotional arousal can influence height perception. In Experiment 1, participants viewed either arousing or nonarousing images before estimating the height of a 2-story balcony and the size of a target on the ground below the balcony. People who viewed arousing images overestimated height and target size more than did those who viewed nonarousing images. However, in Experiment 2, estimates of horizontal distances were not influenced by emotional arousal. In Experiment 3, both valence and arousal cues were manipulated, and it was found that arousal, but not valence, moderated height perception. In Experiment 4, participants either up-regulated or down-regulated their emotional experience while viewing emotionally arousing images, and a control group simply viewed the arousing images. Those participants who up-regulated their emotional experience overestimated height more than did the control or down-regulated participants. In sum, emotional arousal influences estimates of height, and this influence can be moderated by emotion regulation strategies. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

20.
The attentional blink paradigm was used to examine whether emotional stimuli always capture attention. The processing requirement for emotional stimuli in a rapid sequential visual presentation stream was manipulated to investigate the circumstances under which emotional distractors capture attention, as reflected in an enhanced attentional blink effect. Emotional distractors did not cause more interference than neutral distractors on target identification when perceptual or phonological processing of stimuli was required, showing that emotional processing is not as automatic as previously hypothesized. Only when semantic processing of stimuli was required did emotional distractors capture more attention than neutral distractors and increase attentional blink magnitude. Combining the results from 5 experiments, the authors conclude that semantic processing can modulate the attentional capture effect of emotional stimuli. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   

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