International Journal of Cooperative Information Systems

InfoSleuth is an agent-based system that can be configured to perform many different information management activities in a distributed environment. InfoSleuth^TM agents provide a number of complex query services that require resolving ontology-based queries over dynamically changing, distributed, heterogeneous resources. These include distributed query processing, location-independent single-resource updates, event and information monitoring, statistical or inferential data analysis, and trend discovery in complex event streams. It has been used in numerous applications, including the Environmental Data Exchange Network and the Competitive Intelligence System.

Since it is necessary to realize virtual organizations in networks, to develop systems to be used for realizing various kinds of cooperation support among users is very important as a basis of virtual organizations. VIEW Media has been developed for such a purpose, utilizing CSCW (Computer Supported Cooperative Work) and database technologies. By introducing the concept of environment, VIEW Media supports flexible information sharing mechanisms. The major purpose of this paper is to show the advantages of the environment model for flexible sharing. Several well-known models are compared and then a representative model, the room model, is selected for comparison to develop the same application. Since the environment model is more general than the room model, we decided to develop "debate systems" which are rather complicated yet can be realized by both models. Debate systems can be regarded as generalization of conference systems and thus we believe the comparison is appropriate. By real usage of debate systems developed by VIEW Media (the environment model) and TeamWave (the room model), the environment model is shown to be suitable for such applications.

In this paper, we will propose a way of visualizing attribute information for spatial objects in the three-dimensional space and a calculation method for extracting a representative object from objects in a given region. In conventional three-dimensional visualizations such as architectural simulations, most of the attention has been paid to image data such as colors, shapes, and textures of spatial objects. In this research, we will focus on the attribute information of spatial objects including image data. We propose InfoLOD concept which introduces the notion of level of detail(LOD) to attribute information as well as image data such as photographs and computer graphics for controlling the visualization of attribute information in a three-dimensional space. The visualization is controlled based on distance and orientation, and we will also discuss the differentiation factor which visualizes the differences among the objects. In addition to visualization control, we will propose the LandMark algorithm for extracting a representative object from the objects in a given region based on their spatial occupancy ratio and the uniqueness of the attribute data. The region for browsing may be specified manually by the user or may be automatically specified by some algorithm. Here, we discuss the spatial glue operation which dynamically retrieves regions containing objects with user-specified attribute information unlike conventional method based on static mesh which are often used in GIS(Geographic Information System). We will also introduce some of our implementations in order to illustrate our ideas.

Spatial data, ranging from various land information data to different types of environmental data, are typically collected and used by different custodians. The full benefits of using spatial data can be achieved by combining the data from different sources covering a common region. Due to organizational, political and technical reasons, it is unrealistic to physically integrate the vast amount of spatial data managed by different systems in different organizations. A practical approach is to provide interoperability to support multi-site data queries. In this paper, we study the performance aspect of complex spatial query processing. We propose a framework for processing queries with multiple spatial and aspatial predicates using data from multiple sites. Using a new concept called generalized filter, a query is processed in three steps. First, an aspatial filter that incorporates some conditions derived from spatial predicates is used to find a set of candidates, which is a superset of the final query results. Then, the candidates are manipulated and a refinement step is executed following an optimized candidate sequence. Finally, a post-processing step is used to handle spatial expressions in query results. The focus of this paper is to generate enhanced filters in order to minimize the need of transferring and processing complex spatial data.

Business environments have become exceedingly dynamic and competitive in recent times. This dynamism is manifested in the form of changing process requirements and time constraints. Workflow technology is currently one of the most promising fields of research in business process automation. However, workflow systems to date do not provide the flexibility necessary to support the dynamic nature of business processes. In this paper we primarily discuss the issues and challenges related to managing change and time in workflows representing dynamic business processes. We also present an analysis of workflow modifications and provide feasibility considerations for the automation of this process.

Nowadays the complexity of design processes, no matter which design domain (CAD, software engineering, etc.) they belong to, requires system support by means of so-called repositories. Repositories help managing design artifacts by offering adequate storage and manipulation services. Some of the most important features of a repository are version management and activity management. Versioning comprises the specification, storage, and maintenance of versioned design objects whereas activity management is responsible for cooperation control, designflow management and management of design transactions processing versioned design objects. Regarding these issues (version and activity management) repository technology, as we think, should not only provide pre-defined services, but should be flexible enough to reflect different application needs. For that reason, we propose to provide repository managers by generic methods, i.e. by generating the corresponding functionality. In this paper, we consider a representative cooperation model, which is based on versioning services, in order to identify the major data manipulation and activity control needs of cooperative design applications. We will focus on the data manipulation needs by introducing our generative approach for customizing versioning facilities. Additionally, we will outline our ideas of applying a generative approach also for the provision of tailored activity control services. Thus, the paper wants to show that by exploiting generic methods and reuse as well as the extensibility properties of new object-relational database technology, repository managers can be flexibly tailored to special application needs and, thereby, applications do not have to be forced to deal with systems only providing pre-defined services.

In the not too distant past, the amount of online data available to general users was relatively small. Most of the online data was maintained in organizations' database management systems and accessible only through the interfaces provided by those systems. The popularity of the Internet, in particular, has meant that there is now an abundance of online data available to users in the form of Web pages and files. This data, however, is maintained in passive data sources, that is sources that do not provide facilities to search or query their data. The data must be queried and examined using applications such as browsers and search engines. In this paper, we explore an approach to querying passive data sources based on the extraction, and subsequent exploitation, of metadata from the data sources. We describe two situations in which this approach has been used, evaluate the approach and draw some general conclusions.