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   211篇
  免费   6篇
  217篇
  2021年   3篇
  2020年   7篇
  2019年   7篇
  2018年   3篇
  2017年   7篇
  2016年   6篇
  2015年   4篇
  2014年   3篇
  2013年   18篇
  2012年   8篇
  2011年   9篇
  2010年   6篇
  2009年   9篇
  2008年   8篇
  2007年   11篇
  2006年   5篇
  2005年   3篇
  2004年   6篇
  2003年   7篇
  2002年   4篇
  2001年   6篇
  2000年   6篇
  1999年   4篇
  1998年   4篇
  1995年   3篇
  1992年   4篇
  1991年   1篇
  1990年   2篇
  1989年   2篇
  1988年   1篇
  1987年   3篇
  1986年   1篇
  1985年   1篇
  1984年   2篇
  1983年   1篇
  1982年   3篇
  1981年   2篇
  1980年   3篇
  1979年   4篇
  1978年   1篇
  1976年   2篇
  1975年   5篇
  1974年   3篇
  1973年   8篇
  1972年   1篇
  1971年   2篇
  1969年   2篇
  1968年   1篇
  1960年   1篇
  1953年   1篇
排序方式: 共有217条查询结果,搜索用时 15 毫秒
171.
This study used a survey design to investigate if computer experience and computer attitudes influence whether economically marginalized individuals desire access to computerized career services in community outreach centers. The majority (84%) of the sample reported a desire for access to computerized career services at community outreach centers. A multiple regression analysis indicated computer attitudes as most predictive of intention to use computerized career services (β = .29, p < .01). Results support extending access to computerized career services in community outreach centers to meet the needs of economically marginalized individuals.  相似文献   
172.
173.
Tourette's syndrome (TS) is a neuropsychological disorder characterized by vocal and motor tics. TS is also associated with several behavior disorders such as Attention Deficit Hyperactivity Disorder, Oppositional Defiant Disorder, conduct disorder, and Obsessive-Compulsive Disorder. We examined the impact of Tourette's syndrome with and without comorbid psychiatric disorders on the family. TS complicated by comorbid disorders had a greater impact on the family than uncomplicated TS. Tourette's symptom severity was significantly correlated with the level of impact on the family and with the number of comorbid disorders. TS is a disorder with effects that extend beyond motor and vocal tics.  相似文献   
174.
In a previous paper, we reviewed the literature on family assessment and set out some principles that can be derived from previous work. This paper describes the development of a system for family assessment which uses these principles and then gives a brief account of the practical difficulties encountered in applying such a system. (Empirical data on the system will be presented in subsequent papers as they become available.)  相似文献   
175.
Reader's eye movements were monitored while they inspected isolated words in preparation for a synonym judgement task. The 10-letter words appeared on a screen near the point of fixation, with the first fixation being imposed near the beginning, or the centre, or the ending of the word. The words themselves had uneven distributions of information, in that the beginnings or the endings contained common sequences of letters in English. Three types of words were used: those with very redundant endings (e.g., yearningly), with moderately redundant endings (e.g., varnishing), and with moderately redundant beginnings (e.g., contravene). Redundancy was defined in terms of the total number of words in English which possess that particular sequence of five letters as the beginning or the ending. The experiments asked whether the convenient viewing location within a word varied according to the distribution of information, and whether the extent of redundancy in a word ending is reflected in the distribution of visual attention given to the word. The results were analysed separately for those cases where the reader made just two fixations upon the word before moving to the synonym task, and for those cases where the reader made exactly three fixations. These were the dominant fixation patterns. Evidence for the notion of a convenient viewing position consisted of long first fixations (when there were just two fixations), when this fixation was near the centre of the word. The distribution of information within the words did not influence the duration of the first fixation, although the duration of the gaze within each half-word did increase when more informative letter sequences were being inspected. The extent of redundancy was also seen to influence the inspection patterns, when a comparison was made between the two types of words with redundant endings. Words with very redundant endings received fewer fixations when the first fixation was at the beginning, and for words gaining exactly two fixations, the second fixation was shorter if the word had a very redundant ending.  相似文献   
176.
Visual-motor control loop: a linear system?   总被引:2,自引:0,他引:2  
  相似文献   
177.
Twelve subjects performed a high signal rate vigilance task, once after a night's sleep, and once after a night without sleep. Raw scores were transformed into the signal detection parameters, d' and β. After sleep deprivation, detection performance was significantly impaired. This was reflected in a fall of d', whereas β was not significantly altered. Analysing the control data alone for comparison with other vigilance studies revealed a decrement in % signals detected and d', and an increase in β from the first to the second half of the test.  相似文献   
178.
179.
Sixteen subjects performed a test of visual watch-keeping twice, at the same hour of the same day of successive weeks. The test lasted 40 min. On one of these occasions the test was done after normal sleep the previous night; signals were detected at a steady rate throughout. On the other occasion the subjects had no sleep the previous night; they passed the time in innocuous leisure activities. Here a similar level of performance was maintained for the first 20 min. of the test. After this the rate of signal detection declined steadily. In the final quarter of the test the rate was roughly one third that of the first quarter.

Signals missed were divided into three categories, (u) signals missed while watching the display, (b) signals missed while not watching, and, (c) signals missed while asleep. Lack of sleep produced increases in all three of these categories.

These results support previous suggestions that a test has to be prolonged before performance is affected by moderate loss of sleep; they also suggest that it is the simpler, or perhaps the more predictable, tests which are more affected.  相似文献   
180.
Current discussions on the utilization of information technologies for agriculture, place emphasis on the collection and processing of information on the farm, through the introduction and use of computers as management support in process control and database management. However, because of farm management's dependency on outside information support for the production control and market engagement, the communication of information and the improvement of its efficiency is of similar, if not greater, importance. This article, therefore, places its main focus on the communication aspect. It provides a classification for “on-farm” communication patterns and highlights, using this classification, a number of European experiences with videotex applications in agriculture. It argues that new information technologies may open the way for new approaches to farm-related communication, and thus for a major change in farm management practices. For this progression to occur, its development and application should base itself upon the basic communication patterns that have evolved in practice, and reflect the actual use of information in agriculture. Mark Wilkinson is a cereal grower. He is editor of the Irish Farmers Association's closed user group, which was established on Agriline, a Videotex system.  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