Studies on Cooperative Information Systems

本研究旨在实现分布式协同工作环境，以集成和利用分布在网络上的各种信息资源。研究主题包括寻求分布式、异质多媒体信息的协同互操作和通过扩展面向对象模型来建模协同信息系统。1998年，为虚拟办公应用系统设计了环境动态更新机制。协同系统中的事务比传统事务要求更详细的控制和更灵活的处理。已经开发出一种实现这种交易的新方法。我们还分析了数据仓库相关技术的发展趋势，为研究界提出了指导方针，开发了一种新的视图更新方法，提高了传统解决方案的效率，并在一个协作式超媒体系统上设计并实现了动作历史视图功能。1999年，开发的…作为远程教育系统、虚拟办公系统等应用系统开发平台的多媒体协同处理系统已经进行了更多的开发，并通过使用实验获得了用户的反馈。研究了支持用户个性化的多媒体数据库互操作扩展和基于面向对象数据库视图功能扩展的多媒体信息系统模型。该模型被结合到我们的协作超媒体系统的体系结构中。在此基础上，对数据仓库技术在协同系统中的应用、并行处理提高协同处理的效率和保证协同处理的正确性进行了研究。2000年，我们整合了关于协同信息系统的研究成果，并将其重组为开发实际协同系统的基础技术。首先，设计、实现和评估了协作超媒体系统中工作状态转换的管理机制。结果表明，该机制减轻了工作管理者的操作负担，支持工作状态复杂的协同工作。其次，我们将行动历史观机制整合到我们的教育支持系统中，并将其应用于实践中。很明显，行动历史观机制在教育系统等实际应用中是有用的。研究了提高WWW缓存命中率的方法，提出了一种新的Web仓库概念，将WWW和数据仓库技术相结合，为WWW数据提供了更高级的利用。较少

This research aims at realizing distributed cooperative work environments for integrating and utilizing various information resources distributed among networks. Themes of this research include pursuing cooperative interoperability of distributed heterogeneous multimedia information and modeling cooperative information systems by extending object-oriented model.In 1998, mechanisms for dynamic updating of environments are designed for a virtual office application system. Transaction in cooperative systemsare required more detailed control and flexibility than conventional transactions. A new method that realizes such tranactions has been developed. We also have exarnined trends in technologies related to data warehouse, made a submission about guidelines for the research community, developed a new method for view update that improves in efficiency of conventional solutions, and designed and implemented an action history view function on a cooperative hypermedia system.In 1999, the devel … More opment of a multimedia cooperative processing system that is a platform for development of application systems such as a distance education system and a virtual office system has proceeded, and feedback from users was obtained by experiments about usage. We also studied extension of interoperability in multimedia databases supporting personalization for each user and a model for multimedia information systems based on extension of view functions of object-oriented databases. The model was incorporated with the architecture of our cooperative hypermedia system. In addition to these, utilization of a data warehouse technology in cooperative systems and parallel processing for increasing efficiency and a guarantee of correctness in cooperative processing were studied.In 2000, we have integrated our research results about cooperative information systems, reorganized them as basic techniques for developing practical cooperative systems. First, a mechanism for management of transitions of working status in a cooperative hypermedia system was designed, implemented, and evaluated. It shows that the mechanism decreases a operating load of work managers and supports cooperative work that has complex working statuses. Secondly, we integrated action history view mechanisms into our education support system and used the system in practice. It became clear that the action history view mechanisms are useful in practical application such as education systems. We also studied methods for raising WWW cache hit-rate and proposed a new concept web-warehouse, which integrates WWW and data warehouse technologies and provides more advanced utilization of WWW data. Less