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311.
This paper examines the quantification theory of *9 of Principia Mathematica. The focus of the discussion is not the philosophical role that section *9 plays in Principia's full ramified type-theory. Rather, the paper assesses the system of *9 as a quantificational theory for the ordinary predicate calculus. The quantifier-free part of the system of *9 is examined and some misunderstandings of it are corrected. A flaw in the system of *9 is discovered, but it is shown that with a minor repair the system is semantically complete. Finally, the system is contrasted with the system of *8 of Principia's second edition.  相似文献   
312.
The second printing of Principia Mathematica in 1925 offered Russell an occasion to assess some criticisms of the Principia and make some suggestions for possible improvements. In Appendix A, Russell offered *8 as a new quantification theory to replace *9 of the original text. As Russell explained in the new introduction to the second edition, the system of *8 sets out quantification theory without free variables. Unfortunately, the system has not been well understood. This paper shows that Russell successfully antedates Quine's system of quantification theory without free variables. It is shown as well, that as with Quine's system, a slight modification yields a quantification theory inclusive of the empty domain.  相似文献   
313.
Resumen

Las investigaciones sobre memoria de frases han encontrado que las negativas se recuerdan peor que las afirmativas. Entre las posibles causas de este resultado están: a) la mayor complejidad gramatical de las negativas, b) la dificultad que tienen estas frases de ayudarse de imágenes mentales y c) la ausencia, en estos experimentos, de un contexto que ayude a comprender las frases.

En este trabajo se investigaron las tres variables en un solo diseño factorial, utilizando como sujetos 32 estudiantes universitarios. De forma individual, se les presentaban las oraciones, una a una, en la pantalla de un televisor y después de la presentación se les pasaba una prueba de reconocimiento. Los resultados demostraron que las negativas se recuerdan peor solamente si no existe un contexto que posibilite su codificación profunda. Cuando se presentan las frases formando parte de un párrafo no aparecen tales diferencias entre afirmativas y negativas.  相似文献   
314.
By behaving altruistically, individuals voluntarily reduce their benefits in order to increase their partners’. This deviation from a self-interest-maximizing function may be cognitively demanding, though. This study investigates whether altruistic sharing in 4- to 6-year-old children, assessed by a dictator game (DG), is related to three measures of executive functioning, that is, inhibitory control, working memory, and cognitive flexibility. We found that children who turned out to be altruistic in the DG performed better on an inhibition task than non-altruists did. This finding lends support to the hypothesis that altruistic sharing might be somewhat constrained by the child’s ability to inhibit a natural tendency to preserve his or her own resources. Much research is needed to understand the role of inhibitory control in the development of costly sharing and the consolidation of inequity aversion.  相似文献   
315.
Humans are sensitive to complexity and regularity in patterns (Falk & Konold, 1997; Yamada, Kawabe, & Miyazaki, 2013). The subjective perception of pattern complexity is correlated to algorithmic (or Kolmogorov-Chaitin) complexity as defined in computer science (Li & Vitányi, 2008), but also to the frequency of naturally occurring patterns (Hsu, Griffiths, & Schreiber, 2010). However, the possible mediational role of natural frequencies in the perception of algorithmic complexity remains unclear. Here we reanalyze Hsu et al. (2010) through a mediational analysis, and complement their results in a new experiment. We conclude that human perception of complexity seems partly shaped by natural scenes statistics, thereby establishing a link between the perception of complexity and the effect of natural scene statistics.  相似文献   
316.
The results of many experiments have shown that although people distribute their study time depending on the perceived difficulty of the materials, they do not succeed in compensating for this difficulty (e.g., Mazzoni & Cornoldi, 1993). The purpose of this paper was to explore possible ways to induce compensation. The objective difficulty of the items was varied by manipulating their concreteness. In Experiment 1, we explored whether compensation could be increased through practice. In Experiment 2, predictive memory judgements were obtained to determine to what extent participants were sensitive to the characteristics of the material that made it difficult. Finally, in Experiment 3, participants were given instructions designed to achieve complete compensation. Results showed that although participants' judgements of learning and their allocation of time were sensitive to the objective difficulty of the materials, this knowledge was not spontaneously used to compensate. Thus, even with practice participants recalled more easy items than difficult ones. Only instructions that induced greater awareness of the nature of the material were able to produce complete compensation.  相似文献   
317.
This study examined the effects of specific psychosocial factors on the progression of HIV infection in 200 HIV-1 seropositive but asymptomatic men and women. At baseline, participants' disease status was determined, and they were administered self-report assessments of coping style, social support and loneliness. Participants were classified at 6 and 12 month follow-ups as progressed or unchanged, compared to their baseline status. In logistic regression analyses, higher baseline Type C coping scores (indicating emotional inexpressiveness and decreased recognition of needs and feelings) significantly predicted progression at 6 months ( p <0.01) and 12 months ( p <0.02), but only among participants classified at baseline as CDC-A2 (between 200-499 CD4 cells/mm 3 ). In participants originally classified as CDC-A1 (CD4 cell counts > 500/mm 3 ), no psychosocial variable showed any significant relationship. Results emphasize the need to consider the disease context, as well as the interaction between biological and psychological factors in contributing to disease progression.  相似文献   
318.
We assumed that a breach in psychological contract had an effect on soldiers' well-being and not only promoted their burnout levels but decreased their levels of engagement. In a longitudinal study with 387 individuals on a peacekeeping mission, we analyzed the impact of the noncompliance of Army obligations in this mission on the burnout and engagement of soldiers. We found that during the mission their levels of burnout increased, whereas their engagement levels dropped. At the end of the mission, however, this breach in psychological contract did not influence their burnout levels, in spite of a continued reduction in the soldiers' engagement. Theoretical and practical implications are discussed and limitations and suggestions for future research are presented.  相似文献   
319.
This study tested the relation between perceived social impact, social worth, and work engagement in the military, and mediating effects of prosocial motivation. We tested hypotheses using structural equation modeling analysis in a field study with 322 officers and sergeants and 1,045 soldiers of the Portuguese Army. Results confirmed that perceived social impact and social worth were associated with work engagement. Furthermore, regardless of the rank category, perceived social impact was associated with higher prosocial motivation, which in turn was associated with higher work engagement. In the soldiers subsample, results further indicated that soldiers’ perceived social worth was associated with higher prosocial motivation, which in turn was related to higher work engagement. The direct effects of perceived social impact and social worth on work engagement, and the mediating role of prosocial motivation supported the hypothesis that perceptions of social impact and social worth may strengthen the motives to “do good” (prosocial motivation), leading to an upward spiral that cultivates work engagement among members of the military.  相似文献   
320.
This response addresses the comments of Sharma, Rich, and Levy (2004) about the generalizability of the performance effect. The comments are addressed by bringing additional theoretical and empirical support with a new study that replicates and extends the results of our 2003 paper. Results confirm our 2003 findings that bottom performers overestimate and that top performers underestimate their job performance. Further, results confirm our 2003 findings that bottom performers are significantly more inaccurate than top salespeople in their performance estimation. Finally, this study extends previous research by providing evidence that the inaccuracy in self-evaluations is reduced when factualbased questions are used.  相似文献   
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