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671.
Design considerations, construction information, and programming considerations of a high-speed event recorder are presented. The device records discrete events on magnetic tape for later processing by a large computer. Although the design information is general, the instrument has 120 event channels, a time resolution of up to 100 microsec, and can record 60 or more events per second.  相似文献   
672.
The top 1% of the extremely bright students identified by the Study of Mathematically Precocious Youth (Benbow & Stanley, 1980b) were tested along with their parents, using a battery of specifically designed cognitive tests. These students represented the top 0.03% of their age group in intellectual ability. The results showed that the parents were extremely able and resembled one another significantly more than parents in the general population. In addition, the intellectually precocious children resembled their parents to a lesser extent than children of average ability resemble their parents. These results suggest that considerable assortative mating has occurred among the parents of these extremely gifted youth, but that extreme giftedness cannot be predicted reliably solely as a result of the mating of bright parents.  相似文献   
673.
Senile dementia in the elderly is a prevalent condition which requires ongoing medical treatment. This disease causes a deterioration of cognitive processes and, consequently, it is likely to impair the capacities required to give informed consent to needed medical care. However, a diagnosis of senile dementia does not necessarily indicate that the afflicted individual is incompetent. The means of assessing competency in dementia patients and their likely impairments according to five standards is described in this paper. Recommendations for obtaining consent from the competent dementia patient are made and mechanisms for providing special protection to the incompetent patient in the consent process are discussed.  相似文献   
674.
The relationships between intelligence test scores and measures derived from reaction time (RT) and perceptual speed procedures were investigated in 137 twelve-year-old students with IQs ranging from 59 to 142. A range of intelligence tests were used and the scores factor analyzed to produce general, spatial and verbal factors. Test and factor scores were correlated with perceptual speed and with measures taken from 2, 4, and 8 choice RT tasks using a response keyboard upon which the subject's fingers directly rested, thus avoiding interpretive problems associated with a “home key.” Inspection time correlated poorly with intelligence. Only three of the RT measures produced correlations greater than .25 with the general factor. These were the slope of Hick's law, B, (correlation −.28), the 8 choice mean RT, RT8, (−.33) and the 8 choice standard deviation, SD8 (−.41), compared with the average intercorrelation between the intelligence measures of .40. Test-retest correlations of the RT measures, taken over a year for half the subjects, were low as reliability measures, with .35 for B, .52 for RT8, and .48 for SD8. Correlations of RT measures with spatial scores were not significantly greater than with verbal scores, suggesting that whatever relationship exists is with a general factor rather than only a spatial one.  相似文献   
675.
The purpose of the study was to investigate the influence of vocal frequency and vocal intensity upon the perception of speech rate at three levels of actual speech rate. A single sample of spontaneous speech was electronically varied to produce nine stimulus segments that factorially combined three levels each of vocal frequency and intensity. The nine stimuli were recorded such that preceding each was the original segment that served as the standard with which each of the nine stimuli was to be compared. The speech rate of the set of nine stimulus pairs was then electronically altered to obtain a slow set, a moderate set, and a fast set, although the duration of every segment in the three sets was 20 seconds. The sets were rated by different groups of judges in terms of four 7-point scales that measured perceived speech rate, pitch, loudness, and perceived duration. The results indicate that the perception of speech rate is positively related to vocal frequency and intensity at each of the three actual speech rates, and suggest that these relationships are a function of the repeated experience of almost always hearing such covariation in spontaneously occurring speech.The authors are indebted to the Language Laboratory of the University of Maryland Baltimore County and are grateful for the generous amount of computer time provided by the Computer Centers of the Baltimore County and College Park campuses of the university. They are also indebted to Mr. George J. Johnson, Jr., for the design and construction of the instrument used in the study, to Drs. Edwin Susskind and Jahathan Finkelstein for their active concern about the meaning of the results, and to Dr. Klaus Scherer for his very helpful critique.  相似文献   
676.
A study was conducted to investigate the effects on students' spelling achievement of variations in teacher assessment procedures. Teachers measured student spelling performance at a constant level of task difficulty using different measurement frequencies and different rules to interpret the data. Each teacher wrote two consecutive 3-week goals for improved spelling performance for two sets of 100 spelling words and then measured student performance either daily or weekly by dictating randomly selected words from each 100-word list. Teachers were trained to apply either a predetermined set of decision rules or their own judgment to the data to decide if the spelling program they had implemented for the student was effective. Ineffective programs were changed or modified. Results indicated that daily measurement was significantly more effective than weekly measurement in increasing spelling achievement and that, under certain conditions, decision rules were more effective than teacher judgment in determining when to make program changes or modifications.This research was conducted pursuant to Contract 300-77-0491 between the Bureau of Education for the Handicapped (now called Special Education Programs) and the University of Minnesota Institute for Research on Learning Disabilities.  相似文献   
677.
Traditional treatment of the learning disabled child seeks to offer an individualized remediation. The authors offer as an alternative the innovative use of the family therapy modality for treatment of the learning dysfunction. This approaches the source of the learning dysfunction embedded in the faulty communication patterns within the family. The child has the opportunity to experience and more accurately comprehend the communication patterns, become more adept at interpretation of implicit meanings, and to transfer these developing skills to the formal learning situation.  相似文献   
678.
Psychotherapy with the second generation of Holocaust Survivors involves understanding that the Survivors and their offsprings are not a homogeneous group. Numerous variables, such as the age of the Survivor during the Holocaust period, the nature of the experiences, and the length of time the Survivor was imprisoned, all affect the Survivor's adaptive or maladaptive reactions. Recommendations for treating the second generation of Survivors include ascertaining the extent of loss experienced by the parents and their preoccupation with depression and mourning. It is also important to elicit whether the parents were overinvested in their children, affectively impoverished, excessively anxious and overprotective, or able to separate from the Holocaust and invest anew in their new life and family. Further suggestions for treatment are the therapist's need to be aware of countertransference reactions that may duplicate Survivor reactions to their offspring. Flexibility in treating the second generation is also indicated and may call for playing the role of auxiliary ego or, at times, even parent surrogate.  相似文献   
679.
Key pecking by three pigeons was maintained under a multiple fixed-interval fixed-ratio schedule of food presentation. The fixed-interval value remained at 3 minutes, while the fixed-ratio size was increased systematically in 30-response increments from 30 to either 120 (two pigeons) or 150 (one pigeon). At least two lower fixed-ratio values were also redetermined. The effects of ethanol (5 to 2.5 g/kg) were assessed at each of the different schedule parameters. Both overall and running response rates under the fixed-ratio schedule decreased with increases in the size of the fixed-ratio schedule; pause duration under the fixed-ratio schedule was directly related to increases in fixed-ratio size. Overall and running rates of responding under the fixed-interval schedule changed little with increases in the size of the fixed-ratio schedule. Despite the relative invariance of fixed-interval responding across the different fixed-ratio values, the effects of ethanol on responding under the fixed-interval schedule differed depending on the size of the fixed-ratio schedule. Greater increases occurred in both overall and in lower local rates of responding under the fixed-interval schedule when the fixed-ratio value was 120 or 150. The effects of ethanol on responding under the fixed-ratio schedule also depended on the size of the fixed ratio. Increases in responding under the fixed-ratio schedule were typically greater at the higher fixed-ratio values where response rates were lower. When the effects of ethanol were redetermined at the lower fixed-ratio parameter values, rates and patterns of responding were comparable to those obtained initially. However, the dose-effect curves for responding under both fixed-ratio and fixed-interval schedules were shifted up and to the right of those determined during the ascending series. The effects of ethanol can depend on rate or responding, behavioral history, and the context in which behavior occurs.  相似文献   
680.
Historically, the Poisson process has been the “benchmark” model for many stochastic processes. When event counts from a particular process fail to be described adequately by a Poisson distribution, a researcher may turn to generalized Poisson processes to model the empirical data more accurately. Two common generalizations are the (1) heterogeneous Poisson process, in which the process rate is a Gamma random variable, and (2) contagious Poisson process, in which the process rate depends linearly on the current state of the process. Paradoxically, both the heterogeneous and contagious processes yield the same theoretical distribution for the number of events that occur in a single interval of time. Consequently, distinguishing between these two using event counts can be difficult. This situation is discussed, first reviewing the models and distribution, then giving strategies for choosing between them using event count data, and demonstrating these techniques on episodes of hospitalization for schizophrenia.  相似文献   
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