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91.
While there is no universal logic of induction, the probabilitycalculus succeeds as a logic of induction in many contexts throughits use of several notions concerning inductive inference. Theyinclude Addition, through which low probabilities representdisbelief as opposed to ignorance; and Bayes property, whichcommits the calculus to a ‘refute and rescale’ dynamicsfor incorporating new evidence. These notions are independentand it is urged that they be employed selectively accordingto needs of the problem at hand. It is shown that neither isadapted to inductive inference concerning some indeterministicsystems.
1 Introduction
2 Failure of demonstrations of universality
2.1 Working backwards
2.2 The surface logic
3 Framework
3.1 The properties
3.2 Boundaries
3.2.1 Universalcomparability
3.2.2 Transitivity
3.2.3 Monotonicity
4 Addition
4.1 The property: disbelief versus ignorance
4.2Boundaries
5 Bayes property
5.1 The property
5.2 Bayes' theorem
5.3Boundaries
5.3.1 Dogmatism of the priors
5.3.2 Impossibilityof prior ignorance
5.3.3 Accommodation of virtues
6Real values
7 Sufficiency and independence
8 Illustrations
8.1 All properties retained
8.2 Bayes propertyonly retained
8.3 Induction without additivity and Bayes property
9Conclusion
  相似文献   
92.
93.
本文对秦始皇兵马俑博物馆室内采集的长短期降尘、大气悬浮颗粒物和彩绘漆层进行了SEM-EDX研究,在大气悬浮颗粒、短期和长期降尘中,含硫颗粒的粒径分别为0.9~22.8μm、1.0~29.0μm和1.2~37.7μm,多为石膏与粘土或石英以内部混合的状态存在。降尘中的附着型絮状硫酸钙多于大气悬浮颗粒物中,显示降尘和大气中的二氧化硫发生了累进的化学反应。彩绘漆层表面的坑和裂隙附近观察到原位生长的硫酸钙晶体,显示漆层材料或降尘颗粒物与大气二氧化硫之间的酸化学反应,可能是彩绘漆层表面受侵蚀形成微小坑和裂隙的原因之一。  相似文献   
94.
95.
基于SSM分折的科研评价系统探讨   总被引:2,自引:0,他引:2       下载免费PDF全文
科技评价体系是一个复杂的,多目标评价体系。当今科技评价已逐渐从强调科研产出,转向同时关注资源的使用效率,注重科技创新能力的提升和对国民经济发展的贡献。如何建立一个客观、公正、健全、规范的,且具备可操作性的科学评价体系引起了政府和科技界的广泛关注。本文以SSM系统分析为基础,从3E出发探讨了评价指标体系的构建和评价系统的设计。基于系统分析基础上形成的指标体系,既考虑了直接的产出,又分析了内部运行机制,形成的指标体系相对更全面、完整,在此基础上针对具体评价内容选择适宜的评价方法,可定量或定性,软硬结合,具有透明性和延展性,同时易与决策管理部门交流。  相似文献   
96.
Large-scale assessments often use a computer adaptive test (CAT) for selection of items and for scoring respondents. Such tests often assume a parametric form for the relationship between item responses and the underlying construct. Although semi- and nonparametric response functions could be used, there is scant research on their performance in a CAT. In this work, we compare parametric response functions versus those estimated using kernel smoothing and a logistic function of a monotonic polynomial. Monotonic polynomial items can be used with traditional CAT item selection algorithms that use analytical derivatives. We compared these approaches in CAT simulations with a variety of item selection algorithms. Our simulations also varied the features of the calibration and item pool: sample size, the presence of missing data, and the percentage of nonstandard items. In general, the results support the use of semi- and nonparametric item response functions in a CAT.  相似文献   
97.
Due to its strong focus on reasoning and argumentation, critical thinking lacks the breadth required of a comprehensive account of higher order thinking. In particular, critical thinking does not promote reflection on the underlying problems or situations that people think about. This paper reviews various proposed additions to and reorientations of the critical thinking paradigm. It presents a conceptual framework that encompasses the most promising extensions as topics in a broadened account of higher order thinking. This account can be understood as an elaboration of problem solving along two dimensions: Problem types, which are generic thinking situations; and problem solving functions, which are generic thinking tasks. The proposed topic-level account of higher order thinking offers a greatly enlarged view of what should be taught in general thinking skills programs.  相似文献   
98.
This study examined the factor structure of the Emotional Autonomy Scale (EAS) as proposed by Steinberg and Silverberg. Participants were from three independent samples of adolescents in grades 6 (n = 1,842), 8 (n = 1,769), and 10 (n = 1,232), with each sample consisting of three ethnic groups: African American, European American, and Mexican American. None of the confirmatory factor analyses for these samples supported the factor structure proposed by Steinberg and Silverberg. From the three models tested, the EAS is best described by the four originally proposed factors, combined with two method factors, one consisting of the positively worded scale items and one consisting of the negatively worded scale items. Results show that the EAS exhibits poor construct validity and behaves quite differently for the different grade and ethnic groups. The strong impact of method variance on the factor structure is discussed. Although various alternative solutions to the psychometric problems in the EAS are proposed, the most credible solution may be to reexamine the conceptual foundations of emotional autonomy and develop better measures of those concepts for adolescents.  相似文献   
99.
The present research examined the role of maladaptive self-regulatory beliefs as vulnerability factors for academic and emotional difficulties during the transition to middle school. A short-term longitudinal design was employed to follow two groups of early adolescents: 187 adolescents who experienced a school transition between the fifth and sixth grades, and 142 adolescents who did not experience a school transition between the fifth and sixth grades. Adolescents completed measures of perceptions of academic control and importance of academic success, experience of chronic academic strain, daily school hassles, and depressive symptoms. Teachers reported on students' academic engagement, including levels of helpless behavior, effort, and academic performance. Consistent with the proposed model of self-regulation, maladaptive self-regulatory beliefs (i.e., decreased perceptions of academic control and importance) predicted individual differences in perceived school-related stress and depressive symptoms over the course of the middle school transition, but were not associated with academic and emotional difficulties in adolescents who remained in a stable school environment. Moreover, a self-regulatory sequence was identified proceeding from maladaptive self-regulatory beliefs, to academic disengagement, to enhanced perceptions of school-related stress, to depressive symptoms. This study bridges prior theory and research concerning the psychological impact of normative developmental transitions, the developmental context of depression, and the associations among self-regulatory beliefs, achievement-related behavior, and emotional experience.  相似文献   
100.
A comprehensive review of the literature was conducted to identify current practice on teaching science to students with intellectual disability (ID) and/or Autism Spectrum Disorder (ASD) in relation to two review questions—students' science outcomes and students' and teachers' experiences of the interventions. Six databases related to education, psychology, and science were systematically searched. A detailed protocol can be viewed on PROSPERO (registration number: CRD42017057323). Thirty studies were identified that reported on science interventions and 20 on student/teacher experiences of the interventions. The majority of the studies targeted science vocabulary and concepts. Other targets included inquiry skills and comprehension skills. The majority of the interventions used components of systematic instruction (n = 23). Five studies focused on self-directed learning and two on comprehension-based instruction. Students and teachers reported positive experiences of the interventions. The findings suggest that components of systematic instruction in particular might be effective in teaching science content to students with ID and/or ASD. Further research is needed to explore the effectiveness of identified interventions on teaching more complex science skills and with students with severe disabilities. Some limitations related to the search strategy are highlighted.  相似文献   
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