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   77篇
  免费   5篇
  国内免费   2篇
  2023年   3篇
  2022年   1篇
  2021年   1篇
  2020年   1篇
  2018年   5篇
  2017年   2篇
  2016年   3篇
  2014年   3篇
  2013年   5篇
  2011年   2篇
  2010年   7篇
  2009年   7篇
  2008年   2篇
  2007年   6篇
  2006年   12篇
  2005年   2篇
  2004年   12篇
  2003年   3篇
  2002年   3篇
  2001年   1篇
  2000年   1篇
  1981年   1篇
  1977年   1篇
排序方式: 共有84条查询结果,搜索用时 15 毫秒
81.
Managers of invasive species seek to prevent and mitigate their impact, which vary in the time horizon over which they are realized. Likewise, stakeholders vary in the time horizons they consider relevant. Agricultural impacts might reasonably be considered over two or three decades, although ecologists typically consider environmental impacts over much longer time frames. Although time preference plays a critical role in decision making, it has largely been ignored in multicriteria analyses. In this study, we examine how time has been treated in previous decision analyses of invasive species management, focusing on the differences between multicriteria and economic cost–benefit analyses. We then outline a method for incorporating time preference information into multicriteria decision analyses to ensure that criteria weights remain a faithful representation of the decision maker's preferences. To illustrate how time preference can be elicited for invasive species problems involving both monetary and nonmonetary consequences, we describe a small empirical study we conducted with a small group of experts and managers. By outlining a way to consider time preference information in multicriteria analyses of invasive species management, we hope to facilitate better decision making that is reflective of the decision maker's true preferences. Copyright © 2013 John Wiley & Sons, Ltd.  相似文献   
82.
目前,早期胃癌(early gastric cancer,EGC)的治疗仍以开放性手术治疗为主,其预后明显优于进展期胃癌。近年来,随着对EGC浸润与转移规律的深入认识和新技术的应用,其治疗中微创外科的应用更为广泛和合理,并重视患者术后的生活质量。本文结合国内外的研究进展,深入探讨EGC的治疗方法及应用指征,特别是微创外...  相似文献   
83.
84.
Seminal work by Werker and colleagues (Stager & Werker [1997] Nature, 388, 381–382) has found that 14‐month‐old infants do not show evidence for learning minimal pairs in the habituation‐switch paradigm. However, when multiple speakers produce the minimal pair in acoustically variable ways, infants' performance improves in comparison to a single speaker condition (Rost & McMurray [2009] Developmental Science, 12, 339–349). The current study further extends these results and assesses how different kinds of input variability affect 14‐month‐olds' minimal pair learning in the habituation‐switch paradigm testing German learning infants. The first two experiments investigated word learning when the labels were spoken by a single speaker versus when the labels were spoken by multiple speakers. In the third experiment we studied whether non‐acoustic variability, implemented by visual variability of the objects presented together with the labels, would also affect minimal pair learning. We found enhanced learning in the multiple speakers compared to the single speaker condition, confirming previous findings with English‐learning infants. In contrast, visual variability of the presented objects did not support learning. These findings both confirm and better delimit the beneficial role of speech‐specific variability in minimal pair learning. Finally, we review different proposals on the mechanisms via which variability confers benefits to learning and outline what may be likely principles that underlie this benefit. We highlight among these the multiplicity of acoustic cues signalling phonemic contrasts and the presence of relations among these cues. It is in these relations where we trace part of the source for the apparent paradoxical benefit of variability in learning.  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