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991.
Group collaborative editing is an activity by which people geographically dispersed can edit the same document simultaneously. It makes use of computers and network communication to provide an interactive and convenient environment, so people can save much of their time and cost. We have developed a group collaborative editing system which not only allows participants to jointly view and process multimedia documents but also provides real-time interactive conversation facilities to let users feel realistic and friendly. This paper describes the concepts of group collaboration and the mechanisms of our system. It also presents the interface design strategy and the synchronization control method. 相似文献
992.
一类四阶半正边值问题正解的存在性 总被引:4,自引:2,他引:2
证明了四阶半正边值问题 y( 4) -λf(x ,y) =0 ,0 0且充分小时正解的存在性 ,应用的工具是锥上的不动点定理。 相似文献
993.
By using Lambert function, the analytical stability bound is obtained in this paper for delayed second-order systems with repeatable poles. An example is presented to illustrate the obtained analytical result. 相似文献
994.
We present a unified framework for applying iteration reordering transformations. This framework is able to represent traditional
transformations such as loop interchange, loop skewing and loop distribution as well as compositions of these transformations.
Using a unified framework rather than a sequence of ad-hoc transformations makes it easier to analyze and predict the effects
of these transformations. Our framework is based on the idea that all reordering transformations can be represented as a mapping
from the original iteration space to a new iteration space. An optimizing compiler would use our framework by finding a mapping
that both corresponds to a legal transformation and produces efficient code. We present the mapping selection problem as a
search problem by decomposing it into a sequence of smaller choices. We then characterize the set of all legal mappings by
defining a search tree. As part of this process we use a new operation called affine closure. 相似文献
995.
996.
O. B. Lapina A. A. Shubin D. F. Khabibulin V. V. Terskikh P. R. Bodart J. -P. Amoureux 《Catalysis Today》2003,78(1-4):91-104
This overview paper includes both published and original data of the current state of the field of 51V NMR in solid-state chemistry. Advantages and shortcomings of different NMR techniques in their applications to vanadium are discussed on the examples of their application to various vanadia based systems (including individual highly crystalline compounds, solid solutions, glasses, catalysts). New correlations between local structure of vanadium atoms and NMR parameters allowing to discriminate at least seven different types of vanadium sites (tetrahedral sites of Q0, Q1 and Q2 types; trigonal pyramids of 3=1 and 3=2 (V2O5 like) types; tetragonal pyramids of 4=1, 4=2 types) are proposed. It is demonstrated that competent combination of different NMR approaches permits now not only to describe different vanadium sites in highly crystalline and amorphous materials, but also to insight into the structural aspects of disorder in crystallinity as well as to reveal the behavior of different functional groups at elevated temperatures. The influence of low valence vanadium atoms on 51V NMR spectra is also discussed. 相似文献
997.
Stimulating Cooperation in Self-Organizing Mobile Ad Hoc Networks 总被引:24,自引:0,他引:24
In military and rescue applications of mobile ad hoc networks, all the nodes belong to the same authority; therefore, they are motivated to cooperate in order to support the basic functions of the network. In this paper, we consider the case when each node is its own authority and tries to maximize the benefits it gets from the network. More precisely, we assume that the nodes are not willing to forward packets for the benefit of other nodes. This problem may arise in civilian applications of mobile ad hoc networks. In order to stimulate the nodes for packet forwarding, we propose a simple mechanism based on a counter in each node. We study the behavior of the proposed mechanism analytically and by means of simulations, and detail the way in which it could be protected against misuse. 相似文献
998.
Reviews the book, Narrative solutions in brief therapy by Joseph B. Eron and Thomas W. Lund (see record 1996-98412-000). The narrative solutions approach developed in this volume is an attempt to integrate several existing psychotherapies. Most fundamentally, however, this new approach is a variant of brief interactional therapy, which was developed at the Mental Research Institute (MRI) in Palo Alto, CA, beginning in the 1960s. The MRI approach posited that (1) a client's problems originated "from the mishandling of ordinary life difficulties" (p. 18), (2) "The well-intentioned attempts of family members to solve problems actually maintained problems" (p. 18), and (3) "Problems were resolved simply by interrupting problem-maintaining behaviors and getting people back on course" (p. 19). Eron and Lund agree with each of these tenets, but they contend that MRI therapists focused too narrowly on the client's overt behaviors. Though the authors maintain that it is important to deal with the client's actions, they do so within the context of the narrative meaning that the client ascribes to these actions. The authors' primary intent in this book is to answer the question, "What are the key ingredients of a helpful [therapeutic] conversation?" (p. 265). By presenting a coherent framework that they consistently apply to a variety of clinical cases, they provide a compelling answer about how therapists can more effectively talk with their clients. For therapists interested in learning about a solution-focused therapy that emphasizes the client's concrete actions as well as the meanings behind these actions, this book will serve as a useful guide. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
Recent advances in networking environments and telecommunications have led to the proliferation of teams that do not work face-to-face but interact over a computer-mediated communications network. Although some have asserted that virtual teams transcend boundaries of time or distance, others have claimed that working remotely in a mediated team environment differs in significant ways from working face-to-face. In this article, the authors examine the effects of technological mediation on team processes such as cohesiveness, status and authority relations, counternormative behavior, and communication. They discuss conditions under which distance matters in virtual team interaction. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
1000.
在传统的企业信息平台中,企业用户之间、企业用户与客户之间进行信息沟通与访问是通过Intranet/Internet中的Web页面、电子邮件、电话传真、语音邮件等多种不同形式的信息。而对这些信息进行访问时存在不同的用户界面、不同的信息格式、存放在不同位置的问题。而在本文中首先阐述了统一消息系统的概念,然后利用Microsoft Exchange 2000 Server的统一消息功能和其他特殊功能,规划与构建了基于统一消息系统的新的企业信息平台。 相似文献