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41.
The relative aversiveness of signalled vs unsignalled avoidance   总被引:2,自引:2,他引:0       下载免费PDF全文
Subjects avoided shock by pressing on one lever under an unsignalled condition, but by pressing a separate lever they changed the condition to signalled avoidance for 1-min periods. Signalled avoidance periods were identified by a correlated stimulus. All eight subjects responded to change the unsignalled schedule to a signalled one. Once contact with signalled avoidance was made, subjects continued responding to remain in that condition. Other tests showed that changeover responding was greater when the correlated stimulus was presented without the signal than when the signal was presented without the correlated stimulus. An analysis based upon shock and shock-free periods is presented.  相似文献   
42.
43.
This paper defines a Sahlqvist fragment for relevant logic and establishes that each class of frames in the Routley-Meyer semantics which is definable by a Sahlqvist formula is also elementary, that is, it coincides with the class of structures satisfying a given first order property calculable by a Sahlqvist-van Benthem algorithm. Furthermore, we show that some classes of Routley-Meyer frames definable by a relevant formula are not elementary.  相似文献   
44.
The presence of nanotechnologies grew and spread throughout Latin America during the first decade of the 21st century. Science and Technology policies have played an important role in the performance of these new technologies. Various international institutions, such as the World Bank, the Organization for Economic Co-operation and Development, and the Organization of American States promoted similar Science and Technology policies, and included nanotechnology as a priority area. This article shows the role of these Science and Technology policies in the promotion of specific objectives and the gap that was left due to the failure to incorporate an examination of the potential risks to health and environment, not to mention other labor-related effects. The omission of matters relevant to workers and consumers by these institutions led to a distancing from organized civil society.  相似文献   
45.
This paper offers an exposition of Husserl's mature philosophy of mathematics, expounded for the first time in Logische Untersuchungen and maintained without any essential change throughout the rest of his life. It is shown that Husserl's views on mathematics were strongly influenced by Riemann, and had clear affinities with the much later Bourbaki school.
Guillermo E. Rosado HaddockEmail:
  相似文献   
46.
Vallejo G  Lozano LM 《Psicothema》2006,18(2):293-299
In the social, behavioral, and health researches it is a common strategy to collect data along time on more than one group of participants on multiple dependent variables. To analyse this kind of data is very complicated due to the correlations between the measures taken in different points of the time, and between the answers. Usually to analyse these data the multivariate mixed model, or the doubly multivariate model, are the most frequent approaches. Both of them require combined multivariate normality, equal covariance matrices, independence between the observations of different participants, complete measurements on all subjects, and time-independent covariates. When one ore more of these assumptions are not accomplished these approaches do not control in the correct way the Type I error, and this affects the validity and the accuracy of the inferences. In this paper some solutions that solve the problems with the error Type I will be shown. Several programs for a correct realization of the analyses through the SAS Proc Mixed procedure are presented.  相似文献   
47.
The authors assessed the joint perceptions of the employee and his or her employer to examine mutuality and reciprocity in the employment relationship. Paired psychological contract reports were obtained from 80 employee-employer dyads in 16 university-based research centers. On the basis of in-depth study of the research setting, research directors were identified as primary agents for the university (employer) in shaping the terms of employment of staff scientists (employees). By assessing the extent of consistency between employee and employer beliefs regarding their exchange agreement, the present study mapped the variation and consequences of mutuality and reciprocity in psychological contracts. Results indicate that both mutuality and reciprocity are positively related to archival indicators of research productivity and career advancement, in addition to self-reported measures of Met Expectations and intention to continue working with the employer. Implications for psychological contract theory are presented.  相似文献   
48.
Two experiments were completed allowing albino rats to choose between signaled and unsignaled reward conditions. These experiments examined the effects on preference of (1) response dependent versus response-independent reward and, (2) food pellets versus chocolate milk as the reward. All subjects preferred the signaled condition over the unsignaled condition, whether exposed to response-dependent, or to response-independent delivery of rewards. Preference was controlled most effectively by presenting both the signal itself and the correlated stimulus identifying the signaled condition. The signal presented alone (Extinction 3) controlled preference more effectively than did the stimulus correlated with the signaled condition (Extinction 2). The second experiment showed that the quality of the reinforcer (pellets and chocolate milk) did not affect preference for signaled reward since all subjects preferred the signaled condition at levels comparable to those observed in Experiment 1, with food pellets. These results, along with others, argue against species differences, response-dependency, and reinforcer quality as variables affecting the direction of preference.  相似文献   
49.
This study analyzed the validity of the Sherer, et al. Self-efficacy Scale for a Spanish sample of 555 subjects, 257 men and 298 women. 415 were from the general population; 34 schizophrenics and 45 with eating disorders were from a clinic, plus 61 drug addicts from two centers. All met DSM-IV-R criteria. The Eysenck Personality Questionnaire, State-Trait Anxiety Inventory, Assertiveness Inventory, and the Self-control Questionnaire were administered. The reliability for total scores, general factor were high even when social self-efficacy was low. A bidimensional factor structure seemed more acceptable. The Self-efficacy scale scores correlated with those on the Self-control Questionnaire and the Assertiveness Inventory. Extraversion scores on the Sincerity dimension of the Eysenck Personality Questionnaire correlated with scores on the State-Trait Anxiety Inventory and Eysenck's Neuroticism and Psychoticism scales. Significant mean differences appeared between the general population group and the three clinical groups. These analyses support the usefulness of the scale for clinical practice and research with Spanish samples.  相似文献   
50.
We used a mathematical modeling approach, based on a sample of 2,019 participants, to better understand what the cognitive reflection test (CRT; Frederick In Journal of Economic Perspectives, 19, 25–42, 2005) measures. This test, which is typically completed in less than 10 min, contains three problems and aims to measure the ability or disposition to resist reporting the response that first comes to mind. However, since the test contains three mathematically based problems, it is possible that the test only measures mathematical abilities, and not cognitive reflection. We found that the models that included an inhibition parameter (i.e., the probability of inhibiting an intuitive response), as well as a mathematical parameter (i.e., the probability of using an adequate mathematical procedure), fitted the data better than a model that only included a mathematical parameter. We also found that the inhibition parameter in males is best explained by both rational thinking ability and the disposition toward actively open-minded thinking, whereas in females this parameter was better explained by rational thinking only. With these findings, this study contributes to the understanding of the processes involved in solving the CRT, and will be particularly useful for researchers who are considering using this test in their research.  相似文献   
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