全文获取类型
收费全文 | 4745篇 |
免费 | 39篇 |
国内免费 | 38篇 |
专业分类
教育 | 2601篇 |
科学研究 | 675篇 |
各国文化 | 15篇 |
体育 | 1001篇 |
综合类 | 36篇 |
文化理论 | 15篇 |
信息传播 | 479篇 |
出版年
2024年 | 15篇 |
2023年 | 12篇 |
2022年 | 18篇 |
2020年 | 12篇 |
2019年 | 9篇 |
2016年 | 13篇 |
2015年 | 13篇 |
2014年 | 37篇 |
2013年 | 37篇 |
2012年 | 296篇 |
2011年 | 466篇 |
2010年 | 174篇 |
2009年 | 53篇 |
2008年 | 287篇 |
2007年 | 293篇 |
2006年 | 350篇 |
2005年 | 332篇 |
2004年 | 276篇 |
2003年 | 242篇 |
2002年 | 231篇 |
2001年 | 202篇 |
2000年 | 176篇 |
1999年 | 130篇 |
1998年 | 36篇 |
1997年 | 54篇 |
1996年 | 38篇 |
1995年 | 37篇 |
1994年 | 45篇 |
1993年 | 66篇 |
1992年 | 57篇 |
1991年 | 63篇 |
1990年 | 59篇 |
1989年 | 78篇 |
1988年 | 36篇 |
1987年 | 65篇 |
1986年 | 59篇 |
1985年 | 54篇 |
1984年 | 37篇 |
1983年 | 47篇 |
1982年 | 48篇 |
1981年 | 34篇 |
1980年 | 17篇 |
1979年 | 13篇 |
1977年 | 7篇 |
1959年 | 12篇 |
1958年 | 12篇 |
1957年 | 13篇 |
1956年 | 12篇 |
1955年 | 12篇 |
1954年 | 13篇 |
排序方式: 共有4822条查询结果,搜索用时 15 毫秒
61.
Radio is migrating to digital transmission, expanding its offerings to include captioning for individuals with hearing loss. Text display radio requires a large amount of word throughput with minimal screen display area, making good user interface design crucial to its success. In two experiments, we presented hearing, hard-of-hearing, and deaf consumers with National Public Radio stories converted to text and examined their preferences for and reactions to midsized and small radio text displays. We focused on physical display attributes such as text color, font style, line length, and scrolling type as well as emergency alert messages and emergency prompts for drivers, announcer identification schemes, and synchronization of audio and text. Results suggest that midsized, Global Positioning System (GPS)-style displays were well liked, synchronization of audio and text was important to comprehension and retrieval of story details, identification of announcers was served best with a combination of name change in parenthesis and color change, and a mixture of color and flashing symbols was preferred for emergency alerting. 相似文献
62.
Schley S Walter GG Weathers RR Hemmeter J Hennessey JC Burkhauser RV 《Journal of deaf studies and deaf education》2011,16(4):524-536
This article examines the effect that postsecondary education has on earnings and the duration of time spent in the Social Security disability programs for young persons who are deaf or hard of hearing. Our hypothesis is that investments in postsecondary training increase the likelihood of employment for persons who are deaf or hard of hearing and thus reduce dependency on disability-related income support programs. A longitudinal data set based upon records from the National Technical Institute for the Deaf and Social Security administrative records is used for this analysis. We find that those who graduate, even those who graduate with vocational degrees, experience significant earnings benefits and reductions in the duration of time spent on federal disability programs when compared with those who do not graduate with a degree. This finding suggests that reductions in the duration of time spent on Social Security programs are not limited to those with the highest level of scholastic aptitude and that investments in post-secondary education can benefit a broad group of deaf and hard-of-hearing persons. In addition, the data show that individuals who attend college, but withdraw before graduation, fair no better economically than individuals who never attended college. 相似文献
63.
The emerging reading and spelling abilities of 24 deaf and 23 hearing beginning readers were followed over 2 years. The deaf children varied in their language backgrounds and preferred mode of communication. All children were given a range of literacy, cognitive and language-based tasks every 12 months. Deaf and hearing children made similar progress in literacy in the beginning stages of reading development and then their trajectories began to diverge. The longitudinal correlates of beginning reading in the deaf children were earlier vocabulary, letter-sound knowledge, and speechreading. Earlier phonological awareness was not a longitudinal correlate of reading ability once earlier reading levels were controlled. Only letter name knowledge was longitudinally related to spelling ability. Speechreading was also a strong longitudinal correlate of reading and spelling in the hearing children. The findings suggested that deaf and hearing children utilize slightly different reading strategies over the first 2 years of schooling. 相似文献
64.
In this article, we discuss the intuitive knowledge mothers have of their unborn baby. We propose a shift in focus from caregivers' merely providing information to first listening to pregnant mothers as they share their intuitive knowledge of their baby. This approach enables mothers and fathers or partners to know they are already parents to their unborn baby and empowers them to get in touch with their baby's presence and who he or she is during pregnancy. This intuitive knowledge may be a protective behavior that will enable mothers to keep babies safe during pregnancy. 相似文献
65.
Identification of distinct units within a continuous flow of human action is fundamental to action processing. Such segmentation
may rest in part on statistical learning. In a series of four experiments, we examined what types of statistics people can
use to segment a continuous stream involving many brief, goal-directed action elements. The results of Experiment 1 showed no evidence for sensitivity to conditional probability, whereas Experiment 2 displayed learning based on joint probability. In Experiment 3, we demonstrated that additional exposure to the input failed to engender sensitivity to conditional probability. However,
the results of Experiment 4 showed that a subset of adults—namely, those more successful at identifying actions that had been seen more frequently than
comparison sequences—were also successful at learning conditional-probability statistics. These experiments help to clarify the mechanisms subserving processing
of intentional action, and they highlight important differences from, as well as similarities to, prior studies of statistical
learning in other domains, including language. 相似文献
66.
The present research examined the temporal distribution of responding in a lick suppression paradigm. In Experiment 1, rats were trained with either a 30- or a 120-s conditioned stimulus (CS), which was followed either by a footshock (unconditioned
stimulus [US]) or nothing. Licking during the CS was suppressed only in the former condition. Suppression was more pronounced
early in the CS. In Experiment 2, rats were exposed to two 30-s or two 120-s CSs, with delivery of the shock being contingent on CS1 for half of the animals
and on CS2 for the other half. For both the paired and the unpaired conditions, suppression at the beginning of CS1 was observed
for all the groups. By discounting the possibility of generalization between CS1 and CS2, it appears that this initial suppression
was not a conditioned response to the CS, but an unconditioned one due to mere exposure to the shock US. 相似文献
67.
68.
夜闯博物馆我顿了顿,等侍者拿走菜单,才开口:“如果我们偷偷溜出旅馆,自己去博物馆,一定会出事的。”“不,不会的,托尼。”贾尼丝说,“我查过了,博物馆礼拜六晚上通常九点关门,我们只要赶在去看音乐剧的卡尔森小姐和其他同学回来之前回到旅馆就行了。”“来得及吗?”我有点担心。“这次作业我必须拿个好分数。”贾尼丝说,“否则,他们会把我从尖子班开除的。”“我也是。”贾森附和道,“上次我收集的资料不够,起码得再去一趟。”他们全都盯着我。点了点头:“好吧,反正我也要花更多的时间画我的动物草图,那些图要用在论文里。不过,在走之前,我… 相似文献
69.
SHENGPing-xing 《上海大学学报(英文版)》2001,5(2):96-103
This paper deals with Hilbert‘s 16th problem and its generalizations.The configurations of all closed branches of an algebraic curve of degreee n are discussed.The maximum number of sheets for an algebraic equation of degree n and the maximum number of limit cycles for a planar algebraic autonomous system are achieved.The author also considers different generalizations and some related problems. 相似文献
70.