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221.
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Yanfeng Wang 《Philosophical Magazine Letters》2018,98(1):38-43
A theoretical model is developed to predict the electrical conductivity of polymer composites containing carbon nanotubes. It incorporates the effect of two conductivity mechanisms, electron hopping between adjacent nanotubes at the nanoscale and the transmission of electrons through conductive networks formed by nanotubes at the microscale. Based on the model, analytical expressions of both electrical conductivity and piezoresisitivity under stretching are established. The expressions are simple in form, without resorting to heavy computation, and able to give accurate estimations for both electrical conductivity and piezoresistivity. 相似文献
223.
There has been no prior research on peer victimization and child or adolescent schizotypal personality. This study tests the hypothesis that increased peer victimization is associated with increased schizotypal personality. Schizotypy was assessed using the SPQ-C (Schizotypal Personality Questionnaire-Child) in 3,508 male and female schoolchildren aged 8 to 16 years. All forms of peer victimization (physical, verbal, social manipulation, attack on property) were associated with schizotypal personality in both males and females across all age groups. Significant victimization more than doubled schizotypy scores. It is hypothesized that peer victimization may predispose to paranoid ideation, social anxiety, and lack of close friends, and consequently heightened schizotypal personality. 相似文献
224.
We propose a model to measure risk in a prisoner's dilemma based on Coombs' (1973) re‐parameterization of the game as an individual risk decision‐making task that chooses between a gamble of cooperation and another gamble of defection. Specifically, we propose an index, r, to represent the risk associated with cooperation relative to defection. In conjunction with Rapoport's (1967) index of cooperation (K), our formulation of risk allows us to construct games that vary in risk (as indexed by r) while controlling for cooperativeness (as indexed by K). Following utility analysis that models risk seeking as a convex utility function and risk averse as a concave function, we predict that risk‐seeking people cooperate more in games that the cooperation choice is more risky, whereas risk‐averse people cooperate more in games that the cooperation choice is less risky. In the three studies that we varied game parameters, used different measures of risk orientation and prosocial orientation and used different experimental procedures, we found robust results supporting our predictions. Theoretical analysis of our formulation further suggests that risk and cooperativeness of a prisoner's dilemma game is not entirely independent. Games that have a higher cooperativeness index are necessarily more risky. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
225.
There is little known about Hong Kong juvenile offenders on probation. The purpose of this study was to compare Hong Kong juvenile violent with non-violent probationers on static demographic and psychological variables. The study comprised 109 male juvenile probationers aged 14-20 years (M = 16.97, SD = 1.44) in community transitional housing; 34 were adjudicated for violent offenses, while 75 were non-violent. The Rosenberg Self-Esteem Scale (RSES), Satisfaction with Life Scale (SWLS), Social Bonding Scale-Theft (SBS-T), Social Bonding Scale-Violent Crime (SBS-VC), Positive and Negative Affect Scales (PANAS), Impulsiveness Scale-Short Form (IS-SF) and CRIME-PICS II were administered to measure self-esteem, life satisfaction, social bond, positive and negative affect, impulsivity, pro-offending attitudes, and self-perceived life problems. Data on onset age of delinquent behavior, age of first adjudication, number of prior adjudications, and frequency of self-reported delinquency in the past year were also collected. t-tests were consistent with significant differences for violent offenders including higher self-esteem (p < 0.05). Non-violent offenders self-reported significantly more theft (p < 0.05) with a tendency to deny victim hurt more often (p < 0.01); 76.5% of violent offenders self-reported both violent and non-violent crime, while 58.7% of non-violent offenders reported only non-violent crime. For violent and non-violent offenders, the onset of delinquency was inversely related to the frequency of self-reported delinquency. Using ordinary least-squares (OLS) regression analyses, self-anticipated violent reoffending risk was predicted by age of onset, frequency of self-reported delinquency, social bond (inversely), and impulsivity, while non-violent reoffending risk was predicted by the number of prior convictions and self-reported delinquency. Only two psychological correlates, social bond and impulsivity, were related to violent delinquency; interventions are suggested. 相似文献
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采用事件相关电位技术(ERP),通过简单赌博任务,操纵结果预期的效价(输或赢)与风险(高风险与低风险),考察了个体对结果预期阶段的效价和风险评估的脑内时程动态加工过程。脑电结果发现:(1)在N2成分上,结果预期的效价主效应显著,预期输比预期赢能够引起更大的N2波幅;结果预期的风险主效应不显著。(2)在N500成分上,效价与风险之间的交互作用边缘显著,进一步简单效应分析发现,在预期输的条件下,肯定会输的N500波幅显著大于可能会输;而在预期赢的条件下,肯定会赢与可能会赢之间的N500波幅差异不显著。这说明,在不确定决策过程中的结果预期阶段,个体可能先对结果预期的效价进行加工,然后再对风险进行评估。 相似文献
228.
论马克思主义的整体性(上) 总被引:1,自引:0,他引:1
近年来,随着 "马克思主义理论"被正式确立为国家一级学科,"马克思主义学院"在全国高等院校纷纷成立,国内马克思主义研究在表面上也呈现出一派热闹非凡的景象。于是马克思主义的整体性问题被提了出来。然而,与这种表面上热闹的景象形成鲜明对照的是,真正从心灵深处认同、信仰马克思主义的人并不很多。这种悖论式的现象不能不引起我们足够的重视。对于研究马克思主义的理论工作者而言,必须对眼前令人眼花缭乱的马克思主义 "热"进行 "冷"思考,就是说,必须认真地、郑重地提出并弄清这样一个问题: 马克思主义就其本义而言,是站在大众立场、为大众立言、为 相似文献
229.
由于帕金森病早期常仅存在抑郁、睡眠障碍等非运动症状表现,其与重症抑郁障碍难以鉴别.本研究通过对帕金森病患者及重症抑郁障碍患者行汉密尔顿抑郁量表、匹兹堡睡眠指数及多导睡眠监测评定抑郁及睡眠特征,尝试发现两者之间差异,为早期鉴别及诊断帕金森病提供理论基础. 相似文献
230.
已有研究表明,上行比较对高自尊个体产生积极效应。然而鉴于高自尊包括安全性高自尊和防御性高自尊,有必要在上行比较影响不同任务领域内的行为表现这一观点的基础上探讨高自尊的不同类型对上行比较与行为表现之间关系的影响。两个实验均采用高自尊类型、上行比较和任务领域一致性的2×2×2混合因素设计,不同之处在于其分别采用创造性测验和非创造性的语词测验作为不同领域任务。结果表明,防御性高自尊个体没有像安全性高自尊个体那样采取领域转换策略来修复自我关注,由上行比较所引起的领域转换只对安全性高自尊个体产生积极影响。 相似文献