Dynamic Web content provides us with time-sensitive and continuously changing data. To glean up-to-date information, users need to regularly browse, collect and analyze this Web content. Without proper tool support this information management task is tedious, time-consuming and error prone, especially when the quantity of the dynamic Web content is large, when many information management services are needed to analyze it, and when underlying services/network are not completely reliable. This describes a multi-level, lifecycle (design-time and run-time) coordination mechanism that enables rapid, efficient development and execution of information management applications that are especially useful for processing dynamic Web content. Such a coordination mechanism brings dynamism to co-ordinating independent, distributed information management services. Dynamic parallelism spawns/merges multiple execution service branches based on available data, and dynamic run-time reconfiguration coordinates service execution to overcome faulty services and bottlenecks. These features enable information management applications to be more efficient in handling content and format changes in Web resources, and enable the applications to be evolved and adapted to process dynamic Web content.
The coverage of individual Web sites that provide such dynamic content is often incomplete, since individually they are limited by time and resource constraints. To obtain a complete picture about time-sensitive or wide-range topics, people tend to access multiple Web sites. For example, during the terror attacks, since it was such a time-critical situation, no single news site could provide complete information to understand what was happening. People needed to browse different news sites to access different coverage and different opinions, then compile and assemble the information together to understand the full situation. In addition, to understand different reactions from different parts of the world, news sources from various countries needed to be accessed.If a Web site is unresponsive due to congestion, people tend to switch to another Web site and come back later. People exhibit other forms of dynamism as well. For example, they will select a different set of information sources based on their topic area and geographic region of interest, and they will mentally filter and analyze the news articles based on the articles’ content, structure and format.
Any information management tool that supports this process of gleaning information for dynamic Web content should help alleviate the tedious and repetitive aspects, but should be flexible enough to allow users to incorporate the dynamic aspects of information analysis. This describes a dynamic service coordination mechanism that brings dynamism in information management systems for processing dynamic Web content. This coordination mechanism allows users to incrementally develop information management applications on different abstraction levels through the design/runtime lifecycle, which is essential for processing dynamic Web contents efficiently and correctly. This mechanism has been adapted by USC ISI’s GeoWorlds system, and has been proven that it is practically effective on developing information management applications for processing dynamic Web content.
The characteristics of the class of information management :
1. The information is time-sensitive and continuously changing
2. The information needs to be joined together from multiple sources
3. Multiple complex analysis steps are needed to jointly process the information
4. The analysis steps need to be reconfigured to adapt to specific tasks
5. The tasks are repetitive. They need to be performed periodically