首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   28120篇
  免费   392篇
  国内免费   3篇
  2023年   77篇
  2022年   61篇
  2021年   90篇
  2020年   167篇
  2019年   233篇
  2018年   3720篇
  2017年   3050篇
  2016年   2493篇
  2015年   424篇
  2014年   304篇
  2013年   888篇
  2012年   938篇
  2011年   2798篇
  2010年   2768篇
  2009年   1731篇
  2008年   2039篇
  2007年   2515篇
  2006年   317篇
  2005年   451篇
  2004年   406篇
  2003年   325篇
  2002年   255篇
  2001年   224篇
  2000年   222篇
  1999年   143篇
  1998年   105篇
  1997年   102篇
  1996年   94篇
  1995年   58篇
  1994年   77篇
  1993年   53篇
  1992年   82篇
  1991年   95篇
  1990年   91篇
  1989年   66篇
  1988年   71篇
  1987年   57篇
  1986年   43篇
  1985年   66篇
  1984年   60篇
  1982年   58篇
  1981年   44篇
  1980年   49篇
  1979年   55篇
  1978年   45篇
  1977年   53篇
  1976年   51篇
  1975年   44篇
  1974年   38篇
  1973年   42篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
991.
In this paper I consider two accounts of scientific discovery, Robert Hudson’s and Peter Achinstein’s. I assess their relative success and I show that while both approaches are similar in promising ways, and address experimental discoveries well, they could address the concerns of the discovery sceptic more explicitly than they do. I also explore the implications of their inability to address purely theoretical discoveries, such as those often made in mathematical physics. I do so by showing that extending Hudson’s or Achinstein’s account to such cases can sometimes provide a misleading analysis about who ought to be credited as a discoverer. In the final sections of the paper I work out some revisions to the Hudson/Achinstein account by drawing from a so-called structural realist view of theory change. Finally, I show how such a modified account of discovery can answer sceptical critics such as Musgrave or Woolgar without producing misleading analyses about who ought to receive credit as a discoverer in cases from the mathematical sciences. I illustrate the usefulness of this approach by providing an analysis of the case of the discovery of the Casimir effect.  相似文献   
992.
It is commonplace to speak of education as a right. Yet it has been seldom defended as a natural right. Natural rights are pre-social, while education is social intrinsically. This analysis attempts to show how Aristotle’s concept of education can be conceived as a natural and necessary process to fulfill individual autonomy. In this sense it approaches Locke’s conception of a natural right. To the degree that it succeeds, the firmest possible basis for education in modern constitutionally premised social order is established. It will stand on a par with life, liberty and property and will be equally resistant to tyrannical inroads of either government or majoritarian politics. Moreover, it will refocus society on its absolute duty to treat its citizens justly, that is, will full regard for their inalienable rights.  相似文献   
993.
Two complementary bodies of literature either claim explicitly or imply that human cruelty is rooted in asymmetrical relationships. The first describes and analyzes various forms of domination and acquiescence, including colonialism, racism, imperialism, sexism, and interpersonal power dynamics, among others. The second attempts to describe what would constitute the antidote, namely symmetrical relationships of mutuality and equality. Both of these literatures counsel abandoning asymmetrical relationships in favor of the symmetrical. To the contrary, this paper argues that it is only in the context of asymmetrical relationships that humans can learn the basics of equality and mutual regard that undergird democracy. More particularly, the moral use of asymmetrical relations would be to help the young acquire, inter alias, the kinds of self-awareness and self-understanding that would enable them to function as responsible parties in symmetrical relations.  相似文献   
994.
Two experiments examined the role of numerical distance in updating numerical information in working memory. In the first experiment, participants had to memorize a new number only when it was smaller than a previously memorized number. In the second experiment, updating was based on an external signal, which removed the need to perform any numerical comparison. In both experiments, distance between the memorized number and the new one was manipulated. The results showed that smaller distances between the new and the old information led to shorter updating times. This graded facilitation suggests that the process by which information is substituted in the focus of attention involves maintaining the shared features between the new and the old number activated and selecting other new features to be activated. Thus, the updating cost may be related to amount of new features to be activated in the focus of attention.  相似文献   
995.
Studies of recognition typically involve tests in which the participant’s memory for a stimulus is directly questioned. There are occasions however, in which memory occurs more spontaneously (e.g., an acquaintance seeming familiar out of context). Spontaneous recognition was investigated in a novel paradigm involving study of pictures and words followed by recognition judgments on stimuli with an old or new word superimposed over an old or new picture. Participants were instructed to make their recognition decision on either the picture or word and to ignore the distracting stimulus. Spontaneous recognition was measured as the influence of old vs. new distracters on target recognition. Across two experiments, older adults and younger adults placed under divided-attention showed a greater tendency to spontaneously recognize old distracters as compared to full-attention younger adults. The occurrence of spontaneous recognition is discussed in relation to ability to constrain retrieval to goal-relevant information.  相似文献   
996.
This study investigates the importance of vowel diacritics for the retention of Hebrew word lists, with word lists being manipulated along the dimension of word frequency and syllabic length. Eighty university students participated in the study. Half of the participants (40) were tested with the word lists presented in fully-pointed (voweled) Hebrew while the other half (40) were given the word lists in unpointed Hebrew (with vowel diacritics removed). Analyses of each group’s recall rates and recall-order accuracy indicate that, overall, the presence of vowel diacritics had no facilitating effect on the participants’ quantitative and qualitative Short Term Memory (STM) performance. This was found to be true whether word frequency (high vs. medium to low) or syllabic length (mono vs. trisyllabic) were computed as within-subject factors. Attempts to adequately interpret the absence of a pointing effect on STM performance based upon Orthographic Depth Hypothesis (ODH) and Grain Size Theory (GST) proved unfruitful. The authors propose an adaptation of the GST to the peculiarities of Hebrew orthography and discuss a morphology-centered grain-size theory (MGST).  相似文献   
997.
In three experiments, we examined the mechanisms by which prior experience with proactive interference (PI) diminished its effects. Cued recall tasks conforming to an A–B, A–D paradigm were used to induce PI effects. Experiment 1 showed that reduced PI was not due to a reduction in attention to the source of PI. Experiment 2 revealed that participants’ awareness of PI effects on memory performance increased with experience, resulting in a shift in encoding processes. Experiment 3 demonstrated that changes in encoding provided additional support for recollection that further enhanced participants’ ability to constrain their retrieval processing to the appropriate source of information at the time of test. These results can be interpreted as showing that experience with PI enhances awareness of its effects and allows individuals to adjust their learning and retrieval strategies to compensate for such effects.  相似文献   
998.
University of Colorado (CU) students were tested on memory for the “CU Fight Song” in order to examine serial position effects in semantic memory while controlling for familiarity across positions. In Experiment 1, students reconstructed the order of the nine lines of the song. Students with previous exposure to the song performed better and showed a more bowed serial position function than did students with no knowledge of the song. Experiment 2 added a task assessing memory of item information. One word was removed and replaced with a blank in each line, and an alternative word was offered as an option, along with the correct word. Students selected the word that fit into each blank and then reconstructed the order of the lines. There was a bow-shaped curve for order reconstruction, but not for item selection, which implies that the serial position function in semantic memory stems from order, rather than item, information.  相似文献   
999.
In three experiments, we investigated metacognitive monitoring in a variant of an A–B A–C learning paradigm in which the repetition of cues, but not targets, led to increasing proactive interference (PI) across trials. Judgments of learning (JOLs) correctly predicted decreases across trials in this paradigm but incorrectly continued to predict decreases on a final release trial in which new cues were introduced and performance consequently increased. Experience with the paradigm did not ameliorate this metacognitive failure (Experiment 3). In addition, JOLs decreased equally for pairs with repeated and with novel cue terms, even though recall of the latter group of items did not decrease across trials (Experiment 2). These results suggest that metacognizers’ naïve theories of remembering and forgetting include a role for global, but not cue-specific, interference.  相似文献   
1000.
Categories are learned and used in a variety of ways, but the research focus has been on classification learning. Recent work contrasting classification with inference learning of categories found important later differences in category performance. However, theoretical accounts differ on whether this is due to an inherent difference between the tasks or to the implementation decisions. The inherent-difference explanation argues that inference learners focus on the internal structure of the categories—what each category is like—while classification learners focus on diagnostic information to predict category membership. In two experiments, using real-world categories and controlling for earlier methodological differences, inference learners learned more about what each category was like than did classification learners, as evidenced by higher performance on a novel classification test. These results suggest that there is an inherent difference between learning new categories by classifying an item versus inferring a feature.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号