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851.
The paper presents predicate logical extensions of some subintuitionistic logics. Subintuitionistic logics result if conditions of the accessibility relation in Kripke models for intuitionistic logic are dropped. The accessibility relation which interprets implication in models for the propositional base subintuitionistic logic considered here is neither persistent on atoms, nor reflexive, nor transitive. Strongly complete predicate logical extensions are modeled with a second accessibility relation, which is a partial order, for the interpretation of the universal quantifier. Presented by Melvin Fitting  相似文献   
852.
We define a multi-modal version of Computation Tree Logic (ctl) by extending the language with path quantifiers E δ and A δ where δ denotes one of finitely many dimensions, interpreted over Kripke structures with one total relation for each dimension. As expected, the logic is axiomatised by taking a copy of a ctl axiomatisation for each dimension. Completeness is proved by employing the completeness result for ctl to obtain a model along each dimension in turn. We also show that the logic is decidable and that its satisfiability problem is no harder than the corresponding problem for ctl. We then demonstrate how Normative Systems can be conceived as a natural interpretation of such a multi-dimensional ctl logic. Presented by Jacek Malinowski  相似文献   
853.
在高不确定,高度竞争,高度挑战的任务情景下,领导力在团队中将扮演怎样的角色?变革型领导力与交易型领导力又是如何预测团队任务绩效的?为了回答这些问题,该研究对130名学生被试,31个团队,用ERP沙盘模拟游戏来进行模拟实验。通过高度模拟现实中企业经营的情景,从而提高实验结果的外部效度。实验结果表明,变革型领导力与交易型领导力都能够积极地预测团队任务绩效,消极领导力与任务绩效呈负相关,虽然并没有达到统计学显著水平,但研究结果的方向都支持了实验假设。  相似文献   
854.
该研究力图探讨教养及气质因素与失败恐惧的关系,以及失败恐惧对学业成绩的影响及其机制。对427名高一学生施测失败表现评估量表、父母教养方式评价量表、行为抑制/行为激活量表、防御性期望和反思量表、自我阻碍量表,并收集被试期末考试成绩。相关分析、回归分析、路径分析等表明,失败恐惧与教养、气质因素均有密切关系;其对学业成绩具有间接的消极影响。  相似文献   
855.
Within the context of the psychological refractory period (PRP) paradigm, we developed a general theoretical framework for deciding when it is more efficient to process two tasks in serial and when it is more efficient to process them in parallel. This analysis suggests that a serial mode is more efficient than a parallel mode under a wide variety of conditions and thereby suggests that ubiquitous evidence of serial processing in PRP tasks could result from performance optimization rather than from a structural bottleneck. The analysis further suggests that the experimenter-selected distribution of stimulus onset asynchronies (SOAs) influences the relative efficiency of the serial and parallel modes, with a preponderance of short SOAs favoring a parallel mode. Experiments varying the distribution of SOAs were conducted, and the results suggest that there is a shift from a more serial mode to a more parallel mode as the likelihood of short SOAs increases.  相似文献   
856.
857.
This experiment examined the relationship between reinforcer magnitude and quantitative measures of performance on progressive‐ratio schedules. Fifteen rats were trained under a progressive‐ratio schedule in seven phases of the experiment in which the volume of a 0.6‐M sucrose solution reinforcer was varied within the range 6–300 μl. Overall response rates in successive ratios conformed to a bitonic equation derived from Killeen's (1994) Mathematical Principles of Reinforcement. The “specific activation” parameter, a, which is presumed to reflect the incentive value of the reinforcer, was a monotonically increasing function of reinforcer volume; the “response time” parameter, δ, which defines the minimum response time, increased as a function of reinforcer volume; the “currency” parameter, b, which is presumed to reflect the coupling of responses to the reinforcer, declined as a function of volume. Running response rate (response rate calculated after exclusion of the postreinforcement pause) decayed monotonically as a function of ratio size; the index of curvature of this function increased as a function of reinforcer volume. Postreinforcement pause increased as a function of ratio size. Estimates of a derived from overall response rates and postreinforcement pauses showed a modest positive correlation across conditions and between animals. Implications of the results for the quantification of reinforcer value and for the use of progressive‐ratio schedules in behavioral neuroscience are discussed.  相似文献   
858.
The study of positive outcomes associated with strong psychological sense of community (PSOC) has grown worldwide. Yet most research explores PSOC as a uni-dimensional (positive) variable operating in a single referent community. Theoretical and empirical literature has suggested, however, that PSOC can be positive, neutral or negative (Brodsky in J Commun Psychol 24(4):347–363, 1996; Brodsky et al. in Psychological sense of community: Research, applications and implications. Kluwer, New York 2002) and since people live in multiple physical and relational communities, there may be multiple PSOCs (M-PSOC) operating simultaneously and interactively (Brodsky and Marx in J Commun Psychol 29(2):1–18, 2001). This paper explores the operation of M-PSOC in the lives of Afghan women, and male supporters, who belonged to a resistance organization before, during and after the Taliban regime. Decisions to join and stay in this community can be explained, in part, through the differentiation of positive, organizational-level PSOC from negative, macro-community-level PSOC. In addition, M-PSOC suggests unique cultural meanings of the terms “community” and “choice.” Findings have implications for cross-cultural community work and for fostering resilient sub-communities in the face of macro and societal-level risks and oppression.  相似文献   
859.
A General Factor of Personality (GFP) occupies the apex of the hierarchy in three prominent personality disorder inventories. On the Millon Clinical Multiaxial Inventory-III, a GFP accounted for 41% of the variance in two second-order factors, 31% of the variance in five first-order factors, and 26% of the variance in all 24 scales. On the Dimensional Assessment of Personality Pathology, a GFP accounted for 61% of the variance in six first-order factors and 36% of the variance in all 18 scales. In a cross-validation study of the Personality Assessment Inventory, a GFP accounted for 65% of the variance in two second-order factors, 47% of the variance in five first-order factors, and 27% of the variance in all 18 scales.  相似文献   
860.
Catechol-O-methyltransferase (COMT) is a methylation enzyme that catalyzes the degradation pathway and inactivation of dopamine. It is accepted widely as being involved in the modulation of dopaminergic physiology and prefrontal cortex (PFC) function. The COMT Val158Met polymorphism is associated with variation in COMT activity. COMT 158Met allele may be advantageous for PFC-related cognitive abilities; however, it is also associated with increased anxiety, depression, and emotional vulnerability in response to stress or educational adversity. We hypothesized that the COMT polymorphism might be associated with academic performance. In this study, 779 Taiwanese tenth-grade volunteers were recruited. Scores from the Basic Competency Test (BCT), an annual national competitive entrance examination, were used to evaluate academic performance. The results indicated that students bearing homozygous for the Met allele tended to perform more poorly in all BCT subtests as compared to the other groups. In particular, the former performed significantly more poorly in the science and social science subtests. These findings provide evidence that affective factors might overwhelm cognitive abilities in high-stake tests like the BCT.  相似文献   
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