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811.
Discrepancies among informants’ ratings of a given child's behavior complicate the study of linkages between child behavior and academic achievement. In the current study, we examined the potential moderating effect of informant type on associations between behavior and two types of achievement in a longitudinal growth model that captured children's development from 54 months of age through fifth grade. Latent internalizing and externalizing behavioral constructs, as separately measured by mothers and teachers, were modeled as time‐varying predictors of achievements to capture changes that occur as children progress through different developmental stages. Behavioral ratings obtained by both informants explained largely equivalent levels of reading achievement variance, and teachers’ ratings of child behavior explained more variance in analytic type achievements than did those of mothers. 相似文献
812.
Terence P. Thornberry Mauri Matsuda Sarah J. Greenman Megan Bears Augustyn Kimberly L. Henry Carolyn A. Smith Timothy O. Ireland 《Child abuse & neglect》2014
We investigate adolescent risk factors, measured at both early and late adolescence, for involvement in child maltreatment during adulthood. Comprehensive assessments of risk factors for maltreatment that use representative samples with longitudinal data are scarce and can inform multilevel prevention. We use data from the Rochester Youth Development Study, a longitudinal study begun in 1988 with a sample of 1,000 seventh and eighth graders. Participants have been interviewed 14 times and, at the last assessment (age 31), 80% were retained. Risk factors represent 10 developmental domains: area characteristics, family background/structure, parent stressors, exposure to family violence, parent–child relationships, education, peer relationships, adolescent stressors, antisocial behaviors, and precocious transitions to adulthood. Maltreatment is measured by substantiated reports from Child Protective Services records. Many individual risk factors (20 at early adolescence and 14 at later adolescence) are significantly, albeit moderately, predictive of maltreatment. Several developmental domains stand out, including family background/structure, education, antisocial behaviors, and precocious transitions. In addition, there is a pronounced impact of cumulative risk on the likelihood of maltreatment. For example, only 3% of the youth with no risk domains in their background at early adolescence were involved in later maltreatment, but for those with risk in 9 developmental domains the rate was 45%. Prevention programs targeting youth at high risk for engaging in maltreatment should begin during early adolescence when risk factors are already at play. These programs need to be comprehensive, capable of addressing the multiple and interwoven nature of risk that is associated with maltreatment. 相似文献
813.
Stimuli associated with primary reinforcement for instrumental behavior are widely believed to acquire the capacity to function as conditioned reinforcers via Pavlovian conditioning. Some Pavlovian conditioning studies suggest that animals learn the important temporal relations between stimuli and integrate such temporal information over separate experiences to form a temporal map. The present experiment examined whether Pavlovian conditioning can establish a positive instrumental conditioned reinforcer through such temporal integration. Two groups of rats received either delay or trace appetitive conditioning in which a neutral stimulus predicted response-independent food deliveries (CS1→US). Both groups then experienced one session of backward second-order conditioning of the training CS1 and a novel CS2 (CS1–CS2 pairing). Finally, the ability of CS2 to function as a conditioned reinforcer for a new instrumental response (leverpressing) was assessed. Consistent with the previous demonstrations of temporal integration in fear conditioning, a CS2 previously trained in a trace-conditioning protocol served as a better instrumental conditioned reinforcer after backward second-order conditioning than did a CS2 previously trained in a delay protocol. These results suggest that an instrumental conditioned reinforcer can be established via temporal integration and raise challenges for existing quantitative accounts of instrumental conditioned reinforcement. 相似文献
814.
Insincere respondents can have an adverse impact on the validity of substantive inferences arising from self-administered questionnaires (SAQs). The current study introduces a new method for identifying potentially invalid respondents from their atypical response patterns. The two-step procedure involves generating a response inconsistency (RI) score for each participant and scale on the SAQ and subjecting the resulting scores to latent profile analysis to identify classes of atypical RI respondent profiles. The procedure can be implemented post–data collection and is illustrated through a survey of school climate that was administered to N = 52,102 high school students. Results of this screening procedure revealed high levels of specificity and expected levels of concordance when contrasted with the results of traditionally used methods of screening items and response time. Contrasts between valid and invalid respondents revealed similar patterns across the three screening procedures when compared across external measures of academics and risk behaviors. 相似文献
815.
Chase M. Pfeifer Timothy J. Gay Jeff A. Hawks Shane M. Farritor Judith M. Burnfield 《Sports Engineering》2018,21(2):95-102
A mechanical field-goal kicking machine was used to investigate toppling ball flight in American football place-kicking, eliminating a number of uncontrollable impact variables present with a human kicker. Ball flight trajectories were recorded using a triangulation-based projectile tracking system to account for the football’s 3-dimensional position during flight as well as initial launch conditions. The football flights were described using kinematic equations relating to projectile motion including stagnant air drag and were compared to measured trajectories as well as projectile motion equations that exclude stagnant air drag. Measured football flight range deviations from the non-drag equations of projectile motion corresponded to deficits between 9 and 31%, which is described by a football toppling compound drag coefficient of 0.007 ± 0.003 kg/m. Independent variables including impact location and impact angle orientation resulted in 15 impact conditions. We found that an impact location of 5.5 cm from the bottom of the ball maximized trajectory height and distance. At the 5.5-cm impact location, alterations in impact angle produced minimal change in football trajectory, including launch angle (range = 1.96 deg), launch speed (range = 1.06 m/s), and range (range = 0.94 m). 相似文献
816.
In the United States, the decision to commit extensive public resources to sport facilities is a contentious topic of debate. Elected officials often commit substantial public resources to sport facility projects amidst contrary empirical evidence and mixed residential approval. This behavior not only implicates the presence of political activity to advance a course of action, but also suggests an escalation of commitment (EoC), the subject of this study. The authors implemented a collective case study approach to examine three municipalities with long-standing histories of subsidizing professional sport facilities. Data collected from influential elected officials and public leaders (N = 13) as well as documents and records revealed (a) political action to be essential in EoC with decisions involving multiple stakeholder groups; (b) the influence and interaction of political action within each EoC determinant; (c) the substantial role of support, resources, power, and influence in efforts to increase and prevent commitment to a failing course of action; and (d) noticeable spillover effects from use of political activity in EoC. 相似文献
817.
818.
Many individuals tend to have difficulty completing complex procedural tasks that require branching. Neither prose–based nor list–based instructions have been efficient in alleviating this difficulty. Traditional flowcharts have proven more effective in helping individuals to complete complex procedural tasks, but only after several practice sessions. However, it is possible that the use of map–like symbols may eliminate the need for repeated flowchart practice. Therefore, the purpose of this study was to investigate the effects of flowcharts utilizing map–like symbols on performer efficiency in completing a complex procedural task. The results of this study indicated no significant difference between the use of map–like symbols and traditional flowcharts in helping performers to complete complex procedural tasks. However, both graphic presentation formats were found to be significantly more efficient than a list–based presentation of information. It was expected than an intuitive map–like presentation would be more efficient than a list–based format. However, the efficiency of the flowchart presentation under unpracticed conditions was unexpected, based on prior research. 相似文献
819.
820.