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971.
This paper presents a scheme for collaborative 3D design using product model at various levels of detail (LODs). Design features are selectively hidden at each level from certain participants, depending on their actual needs and individual accessibility in the collaboration. A tree data structure represents the feature hierarchy of CAD construction, the link between feature and LOD, and 2D mesh data for display control of each feature. An XML/XSLT-based approach is proposed to enable real-time visualization of different LOD models in distributed environment. A collaborative design system is implemented using multi-agent technologies, which focuses on function design of each agent, interactions among agents, the client–server structure, and generation of the LOD data using the XML/XSLT approach. A scenario of synchronous 3D mold assembly demonstrates that geometric categorization of product model provides an operational mechanism for assuring security of information sharing in engineering collaborations over the Internet. It also validates the effectiveness of the agent technologies for automating complex engineering activities. 相似文献
972.
This paper describes the inter-rater and intra-rater reliability, and the concurrent validity of an observational instrument, the Keyboard Personal Computer Style instrument (K-PeCS), which assesses stereotypical postures and movements associated with computer keyboard use. Three trained raters independently rated the video clips of 45 computer keyboard users to ascertain inter-rater reliability, and then re-rated a sub-sample of 15 video clips to ascertain intra-rater reliability. Concurrent validity was assessed by comparing the ratings obtained using the K-PeCS to scores developed from a 3D motion analysis system. The overall K-PeCS had excellent reliability [inter-rater: intra-class correlation coefficients (ICC)=.90; intra-rater: ICC=.92]. Most individual items on the K-PeCS had from good to excellent reliability, although six items fell below ICC=.75. Those K-PeCS items that were assessed for concurrent validity compared favorably to the motion analysis data for all but two items. These results suggest that most items on the K-PeCS can be used to reliably document computer keyboarding style. 相似文献
973.
K. Geihs P. Barone F. Eliassen J. Floch R. Fricke E. Gjorven S. Hallsteinsen G. Horn M. U. Khan A. Mamelli G. A. Papadopoulos N. Paspallis R. Reichle E. Stav 《Software》2009,39(4):385-422
Driven by the emergence of mobile and pervasive computing there is a growing demand for context‐aware software systems that can dynamically adapt to their run‐time environment. We present the results of project MADAM that has delivered a comprehensive solution for the development and operation of context‐aware, self‐adaptive applications. The main contributions of MADAM are (a) a sophisticated middleware that supports the dynamic adaptation of component‐based applications, and (b) an innovative model‐driven development methodology that is based on abstract adaptation models and corresponding model‐to‐code transformations. MADAM has demonstrated the viability of a general, integrated approach to application‐level adaptation. We discuss our experiences with two real‐world case studies that were built using the MADAM approach. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
974.
It is widely believed that systems development methodologies (SDMs) can help improve the software development process. Nevertheless, their deployment often encounters resistance from systems developers. Agile methodologies, the latest batch of SDMs that are most suitable in dealing with volatile business requirements, are likely to face the same challenge as they require developers to drastically change their work habits and acquire new skills. This paper addresses what can be done to overcome the challenge to agile methodologies acceptance. We provide a critical review of the extant literature on the acceptance of traditional SDMs and agile methodologies, and develop a conceptual framework for agile methodologies acceptance based on a knowledge management perspective. This framework can provide guidance for future research into acceptance of agile methodologies, and has implications for practitioners concerned with the effective deployment of agile methodologies. 相似文献
975.
Adsorbent and corrosion resistant films are useful for sensor development. Therefore, the aim of this work is the production and characterization of plasma polymerized fluorinated organic ether thin films for sensor development. The polymerized reactant was methyl nonafluoro(iso)butyl ether. Infrared Spectroscopy showed fluorinated species and eventually CO but CHn is a minor species. Contact angle measurements indicated that the film is hydrophobic and organophilic but oleophobic. Optical microscopy reveals not only a good adherence on metals and acrylic but also resistance for organic solvents, acid and basic aqueous solution exposure. Double layer and intermixing are possible and might lead to island formation. Quartz Crystal Microbalance showed that 2-propanol permeates the film but there is no sensitivity to n-hexane. The microreactor manufactured using a 73 cm long microchannel can retain approximately 9 × 10−4 g/cm2 of 2-propanol in vapor phase. Therefore, the film is a good candidate for preconcentration of volatile organic compounds even in corrosive environment. 相似文献
976.
提出复杂产品虚拟样机协同开发平台的体系结构和功能框架,设计统一数据访问接口,自主开发了“复杂产品虚拟样机协同开发平台”软件。该软件包括个人工作空间管理、仿真建模、数据管理、过程管理、模型库管理和仿真评估等功能模块,能够支持复杂产品从设计、仿真、分析和优化的整个多学科协同开发过程,实现了对协同开发相关的项目、人员、模型、数据和工作流等资源的集成化管理,为复杂产品虚拟样机的实施提供了设计、仿真和资源管理的分布式支撑环境。 相似文献
977.
978.
979.
Sundeep Sahay 《Information Technology for Development》2016,22(1):168-176
As social scientists engaged in Information Technologies for Development (IT4D), a question we need to necessarily engage with is “are we building a better world with Information and Communication Technologies (ICTs)?” This question, first posed by Professor Geoff Walsham in the IS field, was the topic of my plenary discussion at the IFIP 9.4 meeting in Jamaica 2014, and had now been further developed to this “view from practice” paper for this journal. A first step in this paper has been the reformulation of the question which Professor Walsham raised: “What distortions and obstacles are created by the historical, material, and institutional conditions, and how these shape our efforts of ICTs creating a better world?” This reformulation is done to bring in more explicitly the political dimension into the question, and to nuance the technological deterministic argument implied in the question of technology (always) creating a better world. Taking an empirical example of an ICT intervention from the public health sector in India, deliberately chosen to emphasize distortions typically seen is similar Information and Communication Technologies for Development (ICT4D) projects, the analysis focuses on understanding the conditions of distortions, why they occur, and what can be done differently to contribute to our notion of a better world. 相似文献
980.
Vocabulary development at home: a multimedia elaborated picture supporting parent–toddler interaction
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Some children enter elementary school with large vocabulary delays, which negatively influence their later school performance. A rich home language environment can support vocabulary development through frequent high‐quality parent–toddler interaction. Elaborated picture home activities can support this rich home language environment. This study compares the effects of a multimedia versus a paper elaborated picture on the parent–toddler interaction and toddlers' vocabulary development. In a within‐subjects design, 20 toddlers (age 3–4) discussed a multimedia and a paper elaborated picture with a parent. Results showed that toddlers knew significantly more words (receptively and expressively) after both activities. Moreover, the improvement in receptive vocabulary knowledge was significantly larger with the multimedia elaborated picture compared with the paper‐based picture. In addition, both parent and toddler engaged in a significant higher level of decontextualized language in response to multimedia. The present study shows that multimedia elaborated pictures can support parents at home to engage in a parent–toddler interaction that is richer and supports the development of receptive vocabulary more compared with traditional paper‐based activities. In the future, multimedia‐based home activities for toddlers' vocabulary development, supporting parent–child interaction, can be offered relatively cheap and easily via internet. 相似文献