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   611篇
  免费   53篇
  664篇
  2021年   9篇
  2020年   7篇
  2019年   8篇
  2018年   18篇
  2017年   13篇
  2016年   18篇
  2015年   12篇
  2014年   13篇
  2013年   40篇
  2012年   15篇
  2011年   21篇
  2010年   14篇
  2009年   12篇
  2008年   28篇
  2007年   28篇
  2006年   21篇
  2005年   17篇
  2004年   16篇
  2003年   15篇
  2002年   19篇
  2001年   14篇
  2000年   14篇
  1999年   27篇
  1998年   12篇
  1997年   10篇
  1994年   6篇
  1992年   15篇
  1991年   12篇
  1990年   6篇
  1989年   9篇
  1987年   7篇
  1986年   6篇
  1985年   10篇
  1984年   8篇
  1983年   6篇
  1982年   7篇
  1981年   8篇
  1977年   5篇
  1976年   9篇
  1975年   6篇
  1974年   6篇
  1971年   6篇
  1969年   5篇
  1968年   13篇
  1966年   7篇
  1965年   5篇
  1964年   5篇
  1963年   5篇
  1962年   5篇
  1961年   7篇
排序方式: 共有664条查询结果,搜索用时 0 毫秒
21.
22.
This paper surveys the various forms of Deduction Theorem for a broad range of relevant logics. The logics range from the basic system B of Routley-Meyer through to the system R of relevant implication, and the forms of Deduction Theorem are characterized by the various formula representations of rules that are either unrestricted or restricted in certain ways. The formula representations cover the iterated form,A 1 .A 2 . ... .A n B, the conjunctive form,A 1&A 2 & ...A n B, the combined conjunctive and iterated form, enthymematic version of these three forms, and the classical implicational form,A 1&A 2& ...A n B. The concept of general enthymeme is introduced and the Deduction Theorem is shown to apply for rules essentially derived using Modus Ponens and Adjunction only, with logics containing either (A B)&(B C) .A C orA B .B C .A C.I acknowledge help from anonymous referees for guidance in preparing Part II, and especially for the suggestion that Theorem 9 could be expanded to fully contraction-less logics.  相似文献   
23.
It is shown that J. M. Keynes was the originator of what is called a weighted monetary value (WMV) approach to decision making under uncertainty and risk as opposed to either the expected monetary value (EMV) or subjective expected utility (SEU) approaches.  相似文献   
24.
10 months following a crisis-intervention training program which focused on interpretation of signal events, 17 participants more frequently reported increased belief in their ability to recognize the need for intervention and to intervene effectively than did 22 control subjects. Perceived frequency of intervention by trained participants, however, had decreased rather than increased. Implications of the findings and recommendations for research are discussed.  相似文献   
25.
A J Reynolds 《Adolescence》1991,26(101):133-158
The purpose of this longitudinal study was to develop and test a model of middle school science and mathematics achievement with a national probability sample of 3,116 seventh-grade public school students. Eighth-grade achievement was viewed as a function of readiness attributes on entry into seventh grade and intervening parent, peer, self, and classroom affective and behavioral measures. Data were collected from students and parents over three time periods in seventh and eighth grade. Results of a revised structural model showed that prior achievement in science and math was a strong mediator of effects in the process of schooling. Grades in sixth grade, parental expectations, parent educational attainment, and motivation had moderately strong indirect effects on eighth-grade achievements. Also notable was the positive direct influence of perceptions of classroom context on science and math achievement growth and the negative direct influence of sex (in favor of girls) on science achievement growth. Cross-validation on a split-half sample did not disconfirm the model. It was concluded that while prior achievement had a dominant influence in the schooling process, other variables including parental expectations, motivation, and classroom context do contribute to the schooling process and can be a focal point for improving school success. These and other factors, though helpful, may be most effective well before the middle school years.  相似文献   
26.
There is a growing concern for identifying individuals at risk for suicidal behaviors. Suicidal ideation, that is, the thoughts and cognitions one has about suicidal behaviors and intent, may be considered a primary marker for the risk of more serious suicidal behaviors. This investigation examined the reliability and validity of the Adult Suicidal Ideation Questionnaire (ASIQ; Reynolds, in press-a), a 25-item self-report suicidal ideation measure designed for adults. Subjects were 474 college students from two Midwestern universities. Results indicated high internal consistency (r alpha = .97) and test-retest (rtt = .86) reliability of the ASIQ with college students. Significant correlations (rs = .38 to .60) were found with measures of depression, hopelessness, anxiety, and self-esteem. For the total sample, a multiple correlation of .67 was found between the ASIQ, the independent variables just noted, and history of prior suicide attempt. Factor analysis of the ASIQ produced a four-factor solution. Psychometric support for the utilization of the ASIQ in clinical and research settings is presented and discussed.  相似文献   
27.
This paper examines the impact of social division associated with the emergent "race debate" in Australia (and the so-called "Hanson phenomenon") on the consensus of Australian students' stereotypes of their national ingroup. It compares the stereotypes held by a sample of students in 1997 ( N = 20) with those revealed in studies conducted from 1992 onwards ( N = 102). Results provide strong evidence that stereotype consensus was reduced in the current phase of research and post-testing also indicates that participants themselves interpreted this as being the product of political change in Australian society. The findings are consistent with the argument that stereotypes are sensitive to changes in intergroup and intragroup relations, and that they respond to the reality of social division rather than to the rhetoric of unity.  相似文献   
28.
This article focuses on the development of adolescent resilience and protective factors within a sample of 86 inner-city high school students in Chicago. Resilience was considered present when (a) children living in conditions of risk (b) show better-than-predicted outcomes (c) presumably due to some intervening process. Conditions (a) and (b) were met using quantitative comparisons. Condition (c), the intervening process, was examined using autobiographical essays to begin to understand protective factors youth consider salient in overcoming adversity. Internal attributes such as perseverance, determination, and having the awareness to learn from the risk-attrition process surfaced in the content analyses. Motivational support from family members and teachers was also highly valued for promoting successful adjustment.  相似文献   
29.
30.
Previous research has shown that prior knowledge structures or schemas affect recognition memory. However, since the acquisition of schemas occurs over prolonged periods of time, few paradigms allow the direct manipulation of schema acquisition to study their effect on memory performance. Recently, a number of parallelisms in recognition memory between studies involving schemas and studies involving category learning have been identified. The current paper capitalizes on these findings and offers a novel experimental paradigm that allows manipulation of category learning between individuals to study the effects of schema acquisition on recognition. First, participants learn to categorize computer-generated items whose category-inclusion criteria differ between participants. Next, participants study items that belong to either the learned category, the non-learned category, both, or neither. Finally, participants receive a recognition test that includes old and new items, either from the learned, the non-learned, or neither category. Using variations on this paradigm, four experiments were conducted. The results from the first three studies suggest that learning a category increases hit rates for old category-consistent items and false alarm rates for new category-consistent lures. Absent the category learning, no such effects are evident, even when participants are exposed to the same learning trials as those who learned the categories. The results from the fourth experiment suggest that, at least for false alarm rates, the effects of category learning are not solely attributable to frequency of occurrence of category-consistent items during learning. Implications for recognition memory as well as advantages of the proposed paradigm are discussed.  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