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21.
Research indicates that selecting a strategy to best exploit a new technology is a complex decision-making process. The task involves making a series of decisions with multiple alternatives, each to be evaluated by multiple criteria whose values have high levels of uncertainty. This paper presents a methodology for modelling a new technology decision using decision trees and an optimizing algorithm. A problem of a mining company considering the adoption of new technology is used to illustrate the decision-making task and modelling methodology. A numerical solution to the case demonstrates the potential of the optimizing technique in strategy selection.  相似文献   
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23.
The marine mollusc Aplysia californica exhibits a wide range of nonassociative and associative forms of learning. Recently, we found that the learning repertoire of Aplysia includes operant conditioning (Cook & Carew, 1986, 1989b). The behavior we examined is a naturally occurring, side-to-side head-waving response used by Aplysia in seeking food, obtaining a foothold, and egg laying. Aplysia can be operantly conditioned to reduce head-waving to one side of their body if such a response results in exposure to bright uniform-field illumination, which the animals find aversive. An essential step toward achieving a mechanistic understanding of operant conditioning is to identify and characterize the reinforcement pathway used during the learning. Toward this end, we wished to determine which of the peripheral visual pathways in Aplysia are critical for performance of the operant task. Previous experiments indicated that photic input from the optic and rhinophore nerves functionally inhibited motor neurons that participate in the operant response (head-waving), while photic input from the oral veil nerves excited these same motor neurons (Cook & Carew, 1989c). These findings suggested the hypothesis that one or both of these pathways could play an important role in mediating reinforcement during training. To explore this possibility we operantly trained animals that had received chronic bilateral transections of either the optic and rhinophore nerves or the oral veil nerves C1-C3 (in conjunction with transection of the optic and rhinophore nerves). We found that operant conditioning was not disrupted by ablation of input from the eyes and rhinophores. By contrast, ablation of input from the oral veil (together with that from the eyes and rhinophores) abolished operant conditioning. Thus, the oral veil nerves play a critical modulatory role in operant conditioning of head-waving. This observation further suggested that photic input from the oral veil is conveyed to the CNS via the oral veil nerves. In a final experiment we confirmed that stimulation of the oral veil with light evokes increased afferent activity in the oral veil nerves C1-C2. These results support the idea that the oral veil nerves contain processes that are critical components of the reinforcement pathway for operant conditioning of head-waving.  相似文献   
24.
On the basis of results from a special subject who reported information at a distance during exposure to weak, circumcerebral magnetic fields rotating within the horizontal plane, we designed an experiment to discern if the subjective narratives of normal people exposed to these fields could be similar to the comments of emotionally related individuals who were concurrently generating shared memories about a randomly selected stimulus. Blind matching of the comments indicated that the proportions of 44 students who accurately paired the narratives of the field-exposed subject and the comments of the stimulus person as congruent were statistically significant for 5 of the 7 pairs whose narratives were of sufficient length for analysis. The ratings for congruence of the pairs of verbal behaviors for the 7 pairs of subjects were negatively correlated (rho = -.72) with the geomagnetic activity during the 24-hr. interval within which the experiences were conducted. The results suggested consciousness might also be an insulator to myriad stimuli which might be accessible when brain activity is modified by circumcerebral magnetic fields with temporal configurations in the order of 20 msec.  相似文献   
25.
Cook  Roy T. 《Mind》2002,111(442):225-248
  相似文献   
26.
Understanding attachment security in family context   总被引:4,自引:0,他引:4  
Attachment theory (J. Bowlby, 1969) is not just about how internalized models of relationships affect interpersonal outcomes; it is primarily a theory about how interpersonal processes affect social and cognitive development. This study tested 3 hypotheses about the interpersonal sources of adult attachment security: (a) attachment security is relationship specific, (b) characteristics of partners affect attachment security, and (c) security of attachment is reciprocated. Measures of attachment security were obtained from 2 parents and 2 children (adolescent or older) in 208 middle-class families. Results of social relations model analysis (D. A. Kenny & L. La Voie, 1984) supported all 3 hypotheses. The author concludes that internal working models of relationships may not be so "internal" after all and that greater emphasis on the interpersonal sources of adult attachment security is warranted.  相似文献   
27.
Results were combined from 5 experiments by Cook in 1998 with 728 participants who listened to one male voice and one female voice each saying a sentence, then attempted to recognise the voices from line-ups of six voices presented a week later. While 352 male listeners did not differ significantly in recognising female and male voices (38% correct vs 41%), 376 female listeners were significantly more likely to recognise female than male voices (51% vs 43% correct). There was no evidence for individual differences in voice recognition in that listeners who recognised the male voice were no more likely to recognise the female voice than those who failed to recognise the male voice.  相似文献   
28.
Cook KV 《Adolescence》2000,35(140):717-730
This study was designed to explore Freeman's (1986) finding that the institution that made the greatest contribution to male African-American youths' socioeconomic success was the church. Thirty-two African-American, Haitian-American, and Latino male and female teenagers--16 drawn from inner-city Protestant churches and 16 comparison teenagers from the same communities-were interviewed. The interviews revealed that churched teenagers were less stressed and less likely to have psychological problems than were teenagers in the comparison group. They also appeared more likely to be living with both biological parents, less likely to have a family member on welfare, and more likely to have a job when compared with the other teenagers. They described the church as being central to their lives and as having multiple functions, many of which have been identified in the resilience literature as contributing to positive developmental outcomes. Results are interpreted in light of the transactional model, and recommendations are made, such as expanding the role of the church within these ethnic communities.  相似文献   
29.
In recent theories of event-based prospective memory, researchers have debated what degree of resources are necessary to identify a cue as related to a previously established intention. In order to simulate natural variations in attention, the authors manipulated effort toward an ongoing cognitive task in which intention-related cues were embedded in 3 experiments. High effort toward the ongoing task resulted in decreased prospective memory only when the cognitive processing required to identify the cue was similar to the cognitive processing required to complete the ongoing activity. When the required processing was different for the 2 tasks, cue detection was not affected by manipulated effort, despite there being an overall cost to decision latencies in the ongoing tasks from possessing the intention. Resource allocation policies and factors that affect them are proposed to account for ongoing vs. prospective memory task performance.  相似文献   
30.
Many memory theorists have assumed that forced-choice recognition tests can rely more on familiarity, whereas item (yes-no) tests must rely more on recollection. In actuality, several studies have found no differences in the contributions of recollection and familiarity underlying the two different test formats. Using word frequency to manipulate stimulus characteristics, the present study demonstrated that the contributions of recollection to item versus forced-choice tests is variable. Low word frequency resulted in significantly more recollection in an item test than did a forced-choice procedure, but high word frequency produced the opposite result. These results clearly constrain any uniform claim about the degree to which recollection supports responding in item versus forced-choice tests.  相似文献   
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