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   630篇
  免费   61篇
  国内免费   46篇
  2024年   1篇
  2023年   17篇
  2022年   8篇
  2021年   27篇
  2020年   25篇
  2019年   46篇
  2018年   39篇
  2017年   30篇
  2016年   33篇
  2015年   24篇
  2014年   38篇
  2013年   96篇
  2012年   20篇
  2011年   28篇
  2010年   18篇
  2009年   28篇
  2008年   33篇
  2007年   29篇
  2006年   28篇
  2005年   23篇
  2004年   21篇
  2003年   23篇
  2002年   26篇
  2001年   10篇
  2000年   8篇
  1999年   10篇
  1998年   7篇
  1997年   8篇
  1996年   3篇
  1995年   3篇
  1994年   4篇
  1993年   5篇
  1992年   6篇
  1991年   2篇
  1990年   2篇
  1989年   2篇
  1988年   1篇
  1986年   1篇
  1984年   1篇
  1980年   2篇
  1976年   1篇
排序方式: 共有737条查询结果,搜索用时 46 毫秒
81.
This article sets forth a detailed theoretical proposal of how the truth of ordinary empirical statements, often atomic in form, is computed. The method of computation draws on psychological concepts such as those of associative networks and spreading activation, rather that the concepts of philosophical or logical theories of truth. Axioms for a restricted class of cases are given, as well as some detailed examples.  相似文献   
82.
Nowadays, intelligent connectionist systems such as artificial neural networks have been proved very powerful in a wide area of applications. Consequently, the ability to interpret their structure was always a desirable feature for experts. In this field, the neural logic networks (NLN) by their definition are able to represent complex human logic and provide knowledge discovery. However, under contemporary methodologies, the training of these networks may often result in non-comprehensible or poorly designed structures. In this work, we propose an evolutionary system that uses current advances in genetic programming that overcome these drawbacks and produces neural logic networks that can be arbitrarily connected and are easily interpretable into expert rules. To accomplish this task, we guide the genetic programming process using a context-free grammar and we encode indirectly the neural logic networks into the genetic programming individuals. We test the proposed system in two problems of medical diagnosis. Our results are examined both in terms of the solution interpretability that can lead in knowledge discovery, and in terms of the achieved accuracy. We draw conclusions about the effectiveness of the system and we propose further research directions.  相似文献   
83.
Logic programs and connectionist networks   总被引:2,自引:0,他引:2  
One facet of the question of integration of Logic and Connectionist Systems, and how these can complement each other, concerns the points of contact, in terms of semantics, between neural networks and logic programs. In this paper, we show that certain semantic operators for propositional logic programs can be computed by feedforward connectionist networks, and that the same semantic operators for first-order normal logic programs can be approximated by feedforward connectionist networks. Turning the networks into recurrent ones allows one also to approximate the models associated with the semantic operators. Our methods depend on a well-known theorem of Funahashi, and necessitate the study of when Funahashi's theorem can be applied, and also the study of what means of approximation are appropriate and significant.  相似文献   
84.
Many kinds of creativity result from combination of mental representations. This paper provides a computational account of how creative thinking can arise from combining neural patterns into ones that are potentially novel and useful. We defend the hypothesis that such combinations arise from mechanisms that bind together neural activity by a process of convolution, a mathematical operation that interweaves structures. We describe computer simulations that show the feasibility of using convolution to produce emergent patterns of neural activity that can support cognitive and emotional processes underlying human creativity.  相似文献   
85.
Kukona A  Tabor W 《Cognitive Science》2011,35(6):1009-1051
The Visual World Paradigm (VWP) presents listeners with a challenging problem: They must integrate two disparate signals, the spoken language and the visual context, in support of action (e.g., complex movements of the eyes across a scene). We present Impulse Processing, a dynamical systems approach to incremental eye movements in the visual world that suggests a framework for integrating language, vision, and action generally. Our approach assumes that impulses driven by the language and the visual context impinge minutely on a dynamical landscape of attractors corresponding to the potential eye-movement behaviors of the system. We test three unique predictions of our approach in an empirical study in the VWP, and describe an implementation in an artificial neural network. We discuss the Impulse Processing framework in relation to other models of the VWP.  相似文献   
86.
组织政治知觉对组织认同的影响及工作投入的中介作用   总被引:1,自引:0,他引:1  
以300余名中国大陆制造业企业的员工为被试,运用问卷调查方法和分层回归分析对组织政治知觉、组织认同和工作投入的关系进行了探讨。结果发现:(1)组织政治知觉对工作投入和组织认同有直接的消极影响;(2)组织政治知觉通过组织认同的中介对工作投入有间接的消极影响;(3)在组织政治知觉的三个子维度中,只有薪酬与晋升子维度对工作投入和组织认同具有显著影响。  相似文献   
87.
Numerous theories of religion rest on the assumption that the religious composition of local populations influences the religious identities of a person's close friends, but there have been few empirical tests of this assumption. Using a combination of data on the religious identity of close friends (from the 1988 and 1998 General Social Survey) and information on the religious composition of counties (from the U.S. Religious Congregations and Membership Study) we find that despite tendencies toward religious homogeneity, the religious composition of the surrounding population has an effect on the proportion of a respondent’s same‐religion friends and on the proportion of friends belonging to specific other religious groups. Local population characteristics are unrelated to the proportion of respondents’ friends known in congregational settings. Results have implications for a broad range of sociological theories of religion as well as research examining the impact of same‐congregation and same‐religion friends (e.g., health and well‐being).  相似文献   
88.
Four perspectives (moral community thesis, religious integration, religious commitment, and social networks) guide the selection of variables in this study. Data are from the combined World Values/European Values Surveys for 2000 (50,547 individuals nested in 56 nations). The results of a multivariate hierarchical linear model support all four perspectives. Persons residing in nations with relatively high levels of religiosity, who are affiliated with one of four major faiths, are religiously committed, and are engaged with a religious network are found to be lower in suicide acceptability. The religious integration perspective, in particular, is empirically supported; affiliation with Islam is associated with low suicide acceptability. The findings provide strong support for an integrated model and demonstrate the usefulness of the moral community thesis in understanding suicide acceptability.  相似文献   
89.
BackgroundThe Neonatal Behavioral Assessment Scale (NBAS, Brazelton &; Nugent, 1995) is an instrument conceived to observe the neonatal neurobehavior. Data analysis is usually performed by organizing items into groups. The most widely used data reduction for the NBAS was developed by Lester, Als, and Brazelton (1982).ObjectiveExamine the psychometric properties of the NBAS items in a sample of 213 Portuguese infants.MethodThe NBAS was performed in the first week of infant life (3 days ± 2) and in the seventh week of life (52 days ± 5).ResultsPrincipal component analyses yielded a solution of four components explaining 55.13% of total variance. Construct validity was supported by better neurobehavioral performance of 7-week-old infants compared with 1-week-old infants.ConclusionChanges in the NBAS structure for the Portuguese sample are suggested compared to Lester factors in order to reach better internal consistency of the scale.  相似文献   
90.
The costs of political information vary dramatically across individuals, and these costs help explain why some individuals become politically expert while others demonstrate low levels of political knowledge and awareness. An attractive alternative, particularly for those with high information costs, is to rely on information and advice taken from others who are politically expert. This paper focuses on the complications that arise when the informant and the recipient do not share preferences. A series of small group experiments show that subjects tend to weight expertise more heavily than shared preferences in selecting informants, thereby exposing themselves to diverse views and biased information. Experimental subjects employ several heuristic devices in evaluating the reliability of this information, but depending on their own levels of information, these heuristics often lead subjects either to dismiss advice that conflicts with their own prior judgments or to dismiss advice that comes from an informant with divergent preferences. Hence these heuristics produce important consequences for patterns of political influence, as well as reducing the potential for political change.  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