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   132篇
  免费   6篇
  国内免费   3篇
系统科学   8篇
理论与方法论   3篇
现状及发展   56篇
研究方法   26篇
综合类   47篇
自然研究   1篇
  2021年   1篇
  2020年   3篇
  2019年   3篇
  2018年   3篇
  2017年   1篇
  2016年   1篇
  2015年   3篇
  2014年   1篇
  2013年   3篇
  2012年   5篇
  2011年   1篇
  2010年   3篇
  2009年   6篇
  2008年   9篇
  2007年   5篇
  2006年   1篇
  2005年   5篇
  2004年   6篇
  2003年   3篇
  2002年   6篇
  2001年   8篇
  2000年   5篇
  1999年   4篇
  1998年   15篇
  1997年   2篇
  1994年   1篇
  1992年   2篇
  1991年   1篇
  1990年   3篇
  1987年   2篇
  1986年   1篇
  1985年   1篇
  1982年   2篇
  1981年   1篇
  1978年   1篇
  1976年   3篇
  1975年   4篇
  1973年   2篇
  1971年   3篇
  1970年   7篇
  1969年   1篇
  1968年   2篇
  1967年   1篇
排序方式: 共有141条查询结果,搜索用时 15 毫秒
1.
This article presents a case example involving the renaming of an organizational change process from BPR to outsourcing. The paper discusses the important ramifications of such a name change in that the recognition of outsourcing allowed an organizational commitment to counseling and termination advice. The paper discusses two ways of looking at the name change, one from a critical theory perspective and one from a realist perspective. It demonstrates how theory can provide useful yet markedly different interpretations of such organizational events. Critical theory operates from within what can be termed the transitive epistemological dimension, whereas critical realism tends to emphasize the importance of ontological issues. Each has important things to say about the situation and improves our understanding overall.  相似文献   
2.
3.
Action on issues of ecological significance often requires changes in personal behaviour and political consensus on technologies to support these changes. Unfortunately, many consultation processes only engage a narrow range of stakeholders, usually those professionally engaged or already active on a range of community issues. This paper illustrates how people who are ‘hard to reach’ or seen as ‘apathetic’ might be engaged using ‘action-conversations’ that explore the social climate for action and how scientific/technical messages can be framed in the language of the community.  相似文献   
4.
Summary The novel arsenic compound, dimethyloxarsylethanol, has been isolated from anaerobically incubatedEcklonia radiata. It is proposed that this compound has a key position in the biosynthesis of arsenobetaine.C, H microanalyses were performed by the Australian Microanalytical Service.  相似文献   
5.
In this article I examine similarities between the science and ethics of biotechnology on the one hand, and those of alchemy on the other, and show that the understanding of nature and naturalness upon which many contemporary ethical responses to biotechnology are predicated is, in fact, significantly similar to the understanding of nature that was the foundation of the practice of alchemy. In doing so I demonstrate that the ethical issues and social responses that are currently arising from advances in the field of biotechnology are interestingly similar to those that arose in reaction to the practice and prevalence of alchemy from its inception in Europe in the mid-twelfth century until at least the early modern period. I argue that a proper conception of the ethical issues and a sensible interpretation of the power and the promise of the science of biotechnology are most likely if we understand such attitudes to nature, and to the ethical issues surrounding technological and scientific developments, in terms of an historical and cultural continuum. That is, we should regard biotechnology as merely the latest in a string of technological and scientific developments rather than, as is often alleged, as something entirely new, requiring its own special ethical response. Finally, I suggest that examining the parallels between the ethical issues generated by alchemy and by biotechnology show us that such issues are best situated and discussed within a framework of virtue ethics, as it allows us to think seriously about the relationship between art and nature and the proper role of humans in relation to their technology.  相似文献   
6.
Accurate modelling of volatility (or risk) is important in finance, particularly as it relates to the modelling and forecasting of value‐at‐risk (VaR) thresholds. As financial applications typically deal with a portfolio of assets and risk, there are several multivariate GARCH models which specify the risk of one asset as depending on its own past as well as the past behaviour of other assets. Multivariate effects, whereby the risk of a given asset depends on the previous risk of any other asset, are termed spillover effects. In this paper we analyse the importance of considering spillover effects when forecasting financial volatility. The forecasting performance of the VARMA‐GARCH model of Ling and McAleer (2003), which includes spillover effects from all assets, the CCC model of Bollerslev (1990), which includes no spillovers, and a new Portfolio Spillover GARCH (PS‐GARCH) model, which accommodates aggregate spillovers parsimoniously and hence avoids the so‐called curse of dimensionality, are compared using a VaR example for a portfolio containing four international stock market indices. The empirical results suggest that spillover effects are statistically significant. However, the VaR threshold forecasts are generally found to be insensitive to the inclusion of spillover effects in any of the multivariate models considered. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   
7.
8.
Zusammenfassung An jungen Ratten wurde eine bedeutende Steigerung der Absorption vond-Glukose beobachtet, jedoch keine solche derd-Fruktose. Offenbar ist der Effekt and-Glukose ein adaptives Phänomen, verbunden mit einem veränderten Zellmetabolismus im Dünndarm.  相似文献   
9.
10.
Résumé L'organisation synaptique du noyau latéral geniculé du quokkaSetonix brachyurus fut examiné dans le tissu fixé en glutaraldéhyde et coloré avec de l'E-PTA. Les projections denses présynaptiques sont de contours irréguliers et l'intervalle, qui les sépare de la membrane postsynaptique est continue et large. Les densités de la fente sont quadrilatéraux ou ressemblent à une barre. Entre les projections denses adjacentes plus d'une vésicule touche la membrane présynaptique.

Animals used in this study were obtained from the Rottnest Island Research Station which is partly sponsored by the C.S.I.R.O.  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