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A general purpose program is described for generating, analyzing, and graphing simulated data for experimental, multivariate, and contingency table designs. Applications include simulating actual or hypothetical research studies, conducting Monte Carlo investigations of the consequences of violating assumptions on statistical tests, generating randomized data sets for students to analyze and interpret as homework, and performing simulations demonstrating sampling theory. Data sets may be generated that have normal or nonnormal distributions, independent or correlated observations, and equal or unequal sample sizes. Data-analysis capabilities include one-way, two-way, and three-way ANOVA with any combination of independent- and correlated-groups factors, as well as simple-effects analyses, multiple pairwise comparisons, linear contrasts, and trend analyses.  相似文献   
215.
A number of models of the placement function of the Careers Service are presented. Various hypotheses generated by the models are tested, using data collected from Careers Service records. Specifically, a multivariate analysis is performed to show which personal and social characteristics are associated with a higher probability of being submitted for a permanent vacancy. The implications of the analysis for the Careers Service are discussed.  相似文献   
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Erikson's epigenetic model of psychosocial development posits that each of eight stages unfolds in a particular sequence, and each becomes the primary issue of concern at specified times in the life cycle. Erikson does not address, nor could any empirical studies be located, exploring how the emergence of these eight stages might be affected by a diagnosis of terminal illness. The purpose of this study was to understand how an HIV-positive diagnosis affected movement through Erikson's stages of development. In-depth interviews were conducted with a sample of 18 HIV-positive men and women under 45 years of age. Analysis of the qualitative data revealed three findings regarding Erikson's stages: (1) The fifth stage of idenitity versus role confusion was revisted and the sense of self is redefined; (2) the three adulthood stages of intimacy versus isolation, generativity versus stagnation, and ego integrity versus depair were dealt with simulataneously and, in most cases, resolved favorably; and (3) intimacy and generativity enabled and supported the resolution of the tasks of identity and ego integrity.  相似文献   
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Patients with generalized anxiety disorder (GAD) without concurrent depression (n = 11) and normal controls (n = 17) were tested twice, about 2 months apart, on a modified Stroop colour-naming task, which presented anxiety-related, depression-related and neutral words in masked and unmasked exposure conditions. GAD patients received cognitive behaviour therapy in the test-retest interval, and were also retested at follow-up, about 20 months after initial testing. GAD patients showed interference in colour-naming negative words across both masked and unmasked conditions before treatment, but not post-treatment, compared with controls. Reduced interference effects of masked threat words over time correlated with reduced ratings of anxious thoughts at post-treatment, and at follow-up, in GAD patients. Thus, the preconscious bias for threat information in GAD appears to vary over time in association with changes in anxious thoughts and worries.  相似文献   
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Occupational stress in a U.K. higher education institution was investigated during a period of considerable organizational change. All employees, including academic, support and manual staff, were invited to participate anonymously in the survey. The results, based on the Occupational Stress Indicator, showed that employees reported significantly poorer mental and physical well-being, and greater job dissatisfaction, than a normative group. The findings suggested that female employees were at greater risk from adverse effects of occupational stress. Predictors of distress and job dissatisfaction were identified. The study concluded that occupational stress is a significant problem, and that further investigation is required in other similar institutions.  相似文献   
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Playing computer games has become an increasingly popular leisure time activity amongst adolescents, but concerns have been expressed over possible associated consequences. One research area has investigated reasons for playing, and two prior explanations relate it to the functional concepts of ‘electronic friendship’ and ‘self-esteem’. A questionnaire study was conducted among 120 adolescents to obtain information on a number of measures including gratification of needs and self-esteem. Results showed that playing computer games is equally popular with males and females, but males spend more time on it. Positive correlations between playing and items on the needs scales were obtained. In particular males who were heavy players scored highly on the ‘preference to friends’ need, but interestingly they were also likely to see their friends more often outside school, thus providing no support for the theory that computer games are taking the place of normal social interaction. For females there was evidence of a negative relationship between self-esteem and need gratification through playing computer games. However more adolescents spend much more time watching television than playing computer games. These results are discussed in the context of previous research.  相似文献   
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Improvements in the computing power and visual resolution of modern desktop computing systems, as well as advances in software technology for displaying high-speed animations, have encouraged the development of relatively sophisticated real-time flight simulators for the PC and Macintosh. We review some of the factors that determine how well such programs capture the actual experience of flight. The most significant factor limiting the quality of performance in flying a simulated aircraft is the “frame rate” problem: at low altitudes and in highly detailed visual environments, as in approaching a runway threshold during landing, the computational demands of the animation may necessitate a reduction in the number of frames displayed per second on the screen. The delayed sensory feedback that results proves to be very detrimental to sustaining smooth control of the aircraft, especially during the flare to touchdown where such control is needed most. This finding parallels the well-known effects of delayed auditory feedback (Lee, 1950) and delayed visual feedback (Smith, 1962).  相似文献   
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