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241.
In water striders or other animals that communicate with vibratory or oscillatory signals, surface wave signals can be recorded, analyzed in digital form by computer, then played back accurately by oscillating a magnet, glued to the animal, with electromagnetic fluctuations from a coil driven by the computer. Signals can be played with great flexibility through a normally behaving animal, in laboratory or field. 相似文献
242.
A nonspatial methodology for the analysis of two-way proximity data incorporating the distance-density hypothesis 总被引:1,自引:0,他引:1
This paper presents a nonspatial operationalization of the Krumhansl (1978, 1982) distancedensity model of similarity. This model assumes that the similarity between two objectsi andj is a function of both the interpoint distance betweeni andj and the density of other stimulus points in the regions surroundingi andj. We review this conceptual model and associated empirical evidence for such a specification. A nonspatial, tree-fitting methodology is described which is sufficiently flexible to fit a number of competing hypotheses of similarity formation. A sequential, unconstrained minimization algorithm is technically presented together with various program options. Three applications are provided which demonstrate the flexibility of the methodology. Finally, extensions to spatial models, three-way analyses, and hybrid models are discussed. 相似文献
243.
We present an hierarchical Bayes approach to modeling parameter heterogeneity in generalized linear models. The model assumes that there are relevant subpopulations and that within each subpopulation the individual-level regression coefficients have a multivariate normal distribution. However, class membership is not known a priori, so the heterogeneity in the regression coefficients becomes a finite mixture of normal distributions. This approach combines the flexibility of semiparametric, latent class models that assume common parameters for each sub-population and the parsimony of random effects models that assume normal distributions for the regression parameters. The number of subpopulations is selected to maximize the posterior probability of the model being true. Simulations are presented which document the performance of the methodology for synthetic data with known heterogeneity and number of sub-populations. An application is presented concerning preferences for various aspects of personal computers. 相似文献
244.
E. Wayne Holden Christine Rawlins Jack Gladstein 《Journal of clinical psychology in medical settings》1998,5(2):147-158
We investigated the relationships among perceptions of control over pain, gender, and coping responses in 57 school-aged children receiving services at a specialized pediatric headache clinic. Perceptions of control and gender interacted to predict frequency of active and negative coping responses. A wide range of coping strategies was reported, but only minimal gender or perceived control differences were found in the frequency and helpfulness of individual coping strategies. Results are discussed within the context of recent stress and coping models within the pediatric chronic illness literature. 相似文献
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246.
This pilot study examined the validity of a new scale of perceived exertion during acute bouts of resistance exercise in young children. The researchers developed an 11-point numerical scale with five pictures representing youths at various levels of exertion while lifting weights. 26 children (M age 10.1 +/- 1.2 yr.) performed one set of 10 repetitions at 35%, 55%, and 75% of their one-repetition maximum on the chest press and leg press exercises using child-size weight training machines. Scaling procedures for the perceptual anchors on the perceived exertion scale were based on one repetition maximum testing. Children could use this scale to translate into numbers their perceptions of physical exertion during upper and lower body resistance exercise. Perceived exertion distributed as a positive linear function of the percent of one repetition maximum on the chest press and leg press exercises (rs = .70 to .77), and perceived exertion increased significantly across all three exercise intensities on both exercises. These preliminary findings provide partial evidence for validation when this scale was used during resistance exercise with children. Additional validation regarding perceived exertion during resistance exercise with children is warranted. 相似文献
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248.
Wayne?S.?DeSarboEmail author Duncan?K.?H.?Fong John?Liechty Jennifer?Chang?Coupland 《Psychometrika》2005,70(1):179-202
The collection of repeated measures in psychological research is one of the most common data collection formats employed in survey and experimental research. The behavioral decision theory literature documents the existence of the dynamic evolution of preferences that occur over time and experience due to learning, exposure to additional information, fatigue, cognitive storage limitations, etc. We introduce a Bayesian dynamic linear methodology employing an empirical Bayes estimation framework that permits the detection and modeling of such potential changes to the underlying preference utility structure of the respondent. An illustration of revealed stated preference analysis (i.e., conjoint analysis) is given involving students’ preferences for apartments and their underlying attributes and features. We also present the results of several simulations demonstrating the ability of the proposed procedure to recover a variety of different sources of dynamics that may surface with preference elicitation over repeated sequential measurement. Finally, directions for future research are discussed.The authors wish to acknowledge and thank the Editor, the Associate Editor, and two anonymous reviewers for their constructive and insightful comments. Duncan K.H. Fong’s work was sponsored in part by a research grant from the Smeal College.This revised article was published online in August 2005 with the PDF paginated correctly. 相似文献
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Douglas W. Woods R. Wayne Fuqua Ryan C. Outman 《Journal of psychopathology and behavioral assessment》1999,21(1):1-18
In this study, 120 undergraduate students were asked to rate the social acceptability of a male and female who portrayed different habit behaviors (motor tics, vocal tics, Tourette's disorder, and trichotillomania). The portrayals of these behaviors were clinically valid as viewed by mental health professionals. Each habit behavior was portrayed in a variety of frequency/topography combinations including low frequency/mild topography, low frequency/severe topography, high frequency/mild topography, and high frequency/ severe topography. Participants were randomly assigned to one of four habit conditions (motor tic, vocal tic, Tourette's disorder, and trichotillomania) and were asked to rate the social acceptability of the frequency/topography combinations exhibited by each actor. Results showed that across the various habit conditions, the man with the habit was seen as less socially acceptable than the woman with the habit. In addition, low-frequency habit behaviors were more acceptable than high-frequency behaviors, and behaviors with mild topographies were more acceptable than those with severe topography habits. Motor tics were seen as more acceptable than vocal tics, Tourette's disorder, or trichotillomania. Implications and directions for future research are discussed. 相似文献