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   26295篇
  免费   287篇
  国内免费   14篇
教育   18620篇
科学研究   2422篇
各国文化   250篇
体育   2375篇
综合类   14篇
文化理论   272篇
信息传播   2643篇
  2021年   250篇
  2020年   359篇
  2019年   539篇
  2018年   786篇
  2017年   768篇
  2016年   822篇
  2015年   510篇
  2014年   578篇
  2013年   4291篇
  2012年   620篇
  2011年   691篇
  2010年   478篇
  2009年   460篇
  2008年   533篇
  2007年   492篇
  2006年   457篇
  2005年   1003篇
  2004年   878篇
  2003年   603篇
  2002年   451篇
  2001年   519篇
  2000年   538篇
  1999年   457篇
  1998年   258篇
  1997年   251篇
  1996年   311篇
  1995年   247篇
  1994年   258篇
  1993年   221篇
  1992年   350篇
  1991年   367篇
  1990年   340篇
  1989年   365篇
  1988年   337篇
  1987年   328篇
  1986年   325篇
  1985年   370篇
  1984年   292篇
  1983年   303篇
  1982年   239篇
  1981年   246篇
  1980年   259篇
  1979年   349篇
  1978年   258篇
  1977年   238篇
  1976年   201篇
  1975年   181篇
  1974年   182篇
  1973年   176篇
  1971年   174篇
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
291.
This hands‐on project uses a paper helicopter to teach students how to distinguish between common and special causes of variability when developing and using statistical process control charts. It allows the student to experience a process that is out‐of‐control due to imprecise or incomplete product design specifications and to discover how the process can be brought into control through the use of standardized product specifications and associated construction procedures. It also allows the student to experience common causes of variability, to distinguish these from the special causes of variability resulting from the incomplete design specifications, and to discover how standardization reduces process variability. The project has been used in both undergraduate and MBA classes and demonstrates these concepts in a way that is easy for the student to understand and remember.  相似文献   
292.
293.
Pigeons pecked on three keys, responses to one of which could be reinforced after 3 flashes of the houselight, to a second key after 6, and to a third key after 12. The flashes were arranged according to variable-interval schedules. Response allocation among the keys was a function of the number of flashes. When flashes were omitted, transitions occurred very late. Increasing flash duration produced a leftward shift in the transitions along a number axis. Increasing reinforcement probability produced a leftward shift, and decreasing reinforcement probability produced a rightward shift. Intermixing different flash rates within sessions separated allocations: Faster flash rates shifted the functions sooner in real time, but later in terms of flash count, and conversely for slower flash rates. A model of control by fading memories of number and time was proposed.  相似文献   
294.
295.
Formal models for service composition have been proposed with the variation of the requirements of service developers. Some famous models have provided checking and verification techniques and tools for the behavior of service composition. These models generally focus much on the message flow of web services and neglecting the data contained in the exchanged messages among services, which restrict the application range of these models and also the web service techniques. As new kind of services with different protocols and communication methods have appeared, it is needed to model service composition from a new view which is adapted to the new development in service area. In this paper we offer a function oriented model of service composition which treats the composite service as a software system and specify the function of services which can be directly used to the realization by service providers.  相似文献   
296.
The author articulates key stressors in the lives of families who are homeless. These stresses often combine with barriers such as lack of job opportunities and/or insensitive professionals. Strategies for helping homeless families overcome these barriers and related issues are presented.  相似文献   
297.
OBJECTIVE: This study examined specific aspects of child sexual abuse in relation to symptom severity among hospitalized patients diagnosed with bulimia nervosa. METHOD: Participants were 45 hospitalized bulimic women who reported a history of child sexual abuse. Structured interviews were conducted in order to obtain detailed information regarding specific features of the abusive event(s). Participants also completed instruments that measured depression and eating pathology. RESULTS: There were no significant differences in severity of depression or eating disturbance among women reporting differing abusive experiences including intrafamilial versus extrafamilial abuse, abuse with or without the use of physical force, one versus multiple incidents, early abuse versus abuse occurring after age 14, contact versus noncontact abuse, disclosed versus undisclosed, and combined physical/sexual abuse versus sexual abuse alone. CONCLUSION: The specific characteristics of child sexual abuse are not related to the level of symptomatology for hospitalized bulimic patients. This study suggests that differences in the nature of the abuse may not be as important as the fact that the abuse occurred in the first place.  相似文献   
298.
The separate effects of child neglect, abuse, and their interaction upon language development as measured by the Preschool Language Scale were examined in four groups of children (n = 79) in a quasi-experimental design. There were three groups of maltreated subjects, all drawn from a treatment center: an abused only group (n = 13), a neglected only group (n = 7), and an abused and neglected group (n = 31); a non-maltreated group (n = 28) was drawn from a day care center. Abuse, neglect, and their interaction were used to predict both auditory comprehension and verbal ability as separate criteria in two stepwise multiple regression equations, where the variance attributable to gender and mother's status on Aid to Dependent Children had been removed. Child neglect was found to predict significantly both auditory comprehension and verbal ability. Neither child abuse nor the interaction between abuse and neglect significantly predicted either dependent variable. These findings suggest that child neglect may be the critical type of maltreatment associated with language delay.  相似文献   
299.
This article compares traditional college students' perceptions of effective teaching behaviors with nontraditional students' perceptions. A 15-item questionnaire was completed by undergraduates at a small Southeastern university. Nontraditional students viewed personality and interaction behaviors as more indicative of effective teaching, whereas traditional students focused on behaviors that potentially would enhance grades. The implications of the findings are discussed in light of techniques and approaches that facilitate the needs of both types of students.His major areas of interest include testing and counseling. Nina Mattie, M.A. is a recent graduate of the University of West Florida in the area of school psychology. Stephen J. Vodanovich, Ph.D. is an assistant professor in the psychology department at the University of West Florida. His major areas of interest are social psychology and industrial/organizational psychology. Chris Piotrowski, M.A. is a consultant in forensic psychology. His major areas of interest are personality assessment and online database searching.  相似文献   
300.
The retention of verbal helping skills by human service worker trainees who had completed the Danish and Hauer (1973) training program seven months earlier was explored. Twenty-six trainees engaged in three helping interviews'before training, immediately following training, and seven months later. Consistent with other follow-up studies, high skill levels at posttraining were generally not maintained at follow-up. Contrary to these other studies, however, they remained higher than pretraining levels. Two specific verbal responses, affective responses and closed questions, remained at posttraining levels. The relationship of this study to other follow-up studies is 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