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11.
A survey of CSCW systems 总被引:4,自引:0,他引:4
Tom Rodden 《Interacting with computers》1991,3(3):319-353
Over the last decade, computer supported cooperative work (CSCW) has emerged as an identifiable research area that focuses on the role of the computer in group work. CSCW is a generic term which combines the understanding of the nature of group working with the enabling technologies of computer networking, systems support and applications. The paper examines the classes of system which have emerged to support cooperative working. A framework for characterising and describing CSCW systems is presented and four major classes of cooperative system identified. Each of these classes of cooperative system are examined highlighting their general characteristics and applicability to CSCW. 相似文献
12.
Tom Verhoeff 《Distributed Computing》1988,3(1):1-8
The problem of delay-insensitive data communication is described. The notion of delay-insensitive code is defined, giving precise conditions under which delay-insensitive data communication is feasible. Examples of these codes are presented and analyzed. It appears that delay-insensitive codes are equivalent with antichains in partially ordered sets and with all unidirectional error-detecting codes.
Tom Verhoeff received the B.S. and M.S. degrees in mathematics from Eindhoven University of Technology, The Netherlands, in 1985. He is currently an Assistant Professor at the Department of Mathematics and Computing Science of the same university. His main research interests are parallel computations, especially formalisms for their specification and design, and their implementation as delay-insensitive VLSI circuits. 相似文献
13.
Tom Carter 《Urban Policy and Research》2005,23(3):265-286
Current demographic trends in Canada include population aging and declining household growth. These trends generally result in falling housing demand and stable or declining house prices. Housing markets in Canada's major cities, however, have been characterized by increases in demand and prices in recent years; due in large part to the influence of arriving immigrants. The destinations of 76 percent of international immigrants to Canada are the three global cities—Toronto, Vancouver and Montreal—where they have a very significant effect on housing demand, particularly as under current immigration policy many of those arriving come with considerable wealth. Their influence, however, is much broader and includes the growth of exclusive, prosperous immigrant neighbourhoods, new architectural designs and other neighbourhood changes. Not all immigrants, however, arrive with wealth. Many are poor, live in less attractive neighbourhoods and pay unrealistic amounts of their inadequate incomes for poor quality housing. Some end up homeless on the street. The role of immigrants in housing markets is an important consideration for urban and housing policy. 相似文献
14.
Tom Fitzpatrick 《电子测试》2005,(11):34-42
虽然目前的IC设计持续以惊人的速度复杂化,但设计者仍然希望可以通过先进的验证工作提高工作效率.所谓的先进验证工作便是将测试平台自动化(Test-Bench Automation)和正式属性检测(Formal Property Checking)两功能添加到功能验证(Functional Verification)的流程之中.本文将主要探讨其中的基本概念、价值以及使用方法,进而帮助读者了解. 相似文献
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In the last decade there was growing interest in strategic management literature about factors that influence a company's ability to use IT. There is general consensus that knowledge and competency are necessary in developing an IT capability, but there is very little understanding of what the necessary competencies are, and how they influence IS usage in different contexts. The small and medium-sized enterprise context is particularly interesting for two reasons: it constitutes a major part of the economy and it has been relatively unsuccessful in exploiting e-business. 相似文献
18.
This study examined people's willingness to restrain themselves during a naturally occurring social dilemma situation—the 1991 California water shortage. The findings suggest that people are more willing to support authorities who make water conservation decisions when these authorities use fair decision-making procedures. Procedural justice effects were not found to be influenced by the perceived severity of the resource scarcity or the favorability of the authorities' decisions. Rather, they were primarily based on concerns for having positive, relational bonds to the authorities. These relational effects were found to be stronger for those respondents who identify more with their community. The study suggests that the effectiveness of authorities is primarily linked to the nature of their social bonds with community members. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
19.
From dust till drawn 总被引:1,自引:0,他引:1
William Van Haevre Tom Van Laerhoven Fabian Di Fiore Frank Van Reeth 《The Visual computer》2007,23(9-11):925-934
We present a system for drawing pastel media in real-time as an effective alternative to most existing digital solutions that basically allow for drawing arbitrary strokes in a particular style. Our approach is focused on the simulation of the natural material itself and on its interaction with the drawing surface and the drawing tool. Upon free-form drawing, a bidirectional transfer of pigment takes place. In one direction, the paper surface is dusted with new pigment particles broken off the tip (i.e., the end of the drawing tool). A large part of these particles will be deposited or blended together with previously deposited ones whereas the remainder does not contribute to the drawing and is blown off. On the other hand, a certain amount of previously deposited pigment is scraped off and picked up again soiling the tip. This is noticeable in the next strokes to be drawn. Furthermore, both the tip and the paper surface are subject to weathering depending on the exerted pressure and friction of the drawing tool, and the bumpiness of the paper. As a result, the paper surface becomes slightly damaged, limiting the deposition of new pigment. The tip, on the other hand, becomes blunt making new strokes wider. From a stylistic point of view, similarly to traditional drawings our results convey the artists’ characteristics (e.g., the way of wielding the brush, skillfulness, feeling for the medium). Therefore, we believe that our system allows an artist to create realistically looking pastel images without losing his/her personal touch. 相似文献
20.
MP Amador Rodríguez A Artal Cortés E Rebollar Torres A Idoipe Tomás P Palomo Palomo J Martínez Trufero 《Canadian Metallurgical Quarterly》1998,13(4):198-204
A B16 melanoma-specific CD8+ T cell line (AB1) was established from the spleen cells of C57BL/6 mice cured of B16 melanoma with interleukin (IL)-12 treatment. The AB1 line exclusively used T cell receptor Vbeta11. The AB1 cells exhibited a cytolytic activity against both syngeneic B16 melanoma and allogeneic P815 mastocytoma, whereas a cold inhibition assay revealed specificity of the AB1 cells against B16 melanoma. Their lostability to kill a class I loss variant of B16 melanoma was restored by the transfection of H-2Kb gene. In addition, their interferon (IFN)-gamma production was significantly suppressed by the addition of anti-H-2Kb monoclonal antibody, and RT-PCR analysis showed that the AB1 line expressed the mRNA encoding IFN-gamma, but not IL-4 or IL-10. The experiment using synthetic peptides of tyrosinase-related protein-2 (TRP-2) revealed that the AB1 cells could recognize TRP-2(181-188) peptide. Moreover, the AB1 cells showed an in vivo antitumor effect against established pulmonary metastases of B16 melanoma. Overall, these results indicate that the Tc1-type Vbeta11+ AB1 cells exert an antitumor activity against syngeneic B16 melanoma through recognition of TRP-2(181-188) peptide in an H-2Kb-restricted manner. 相似文献