Event notification services: analysis and transformation of profile definition languages

The integration of event information from diverse event notification sources is, as with meta-searching over heterogeneous search engines, a challenging task. Due to the complexity of profile definition languages, known solutions for heterogeneous searching cannot be applied for event notification. In this technical report, we propose transformation rules for profile rewriting. We transform each profile defined at a meta-service into a profile expressed in the language of each event notification source. Due to unavoidable asymmetry in the semantics of different languages, some superfluous information may be delivered to the meta-service. These notifications are then post-processed to reduce the number of spurious messages. We present a survey and classification of profile definition languages for event notification, which serves as basis for the transformation rules. The proposed rules are implemented in a prototype transformation module for a Meta-Service for event notification

Information Alert in Distributed Digital Libraries:The Models,Languages,and Architecture of DIAS

www.intelligence.tuc.gr/˜manolis Abstract. This paper presents DIAS, a distributed alert service for dig-ital libraries, currently under development in project DIET. We first discuss the models and languages for expressing user profiles and notifi-cations. Then we present the data structures, algorithms and protocols that underly the peer-to-peer agent architecture of DIAS.

Does Alerting have special Requirements for Query Languages?

Abstract Alerting Systems keep its users informed about new documents and events they are interested in.The power of such services depends on the expressiveness of the language used to define a user's interest. In this paper, we show restrictions of existing languages and discuss additional languageparameters. We will emphasize briefly the problem of different underlying time systems and propose a common profile structure that can serve as basis for a Profile Definition Language for Alerting. 1 Introduction In the last years, Alerting Systems (also called Event Notification Services) have gained strengthenedattention. Several systems have been implemented, such as Springer Link Alert [13] and NiagaraCQ [3]. Users define their information need as a profile. The usability and power of alerting services heavilydepends on the expressiveness of the profile definition language. Various languages have been implemented; they are often very simple and based on the Boolean model (e.g. [11]). Only some are moresophisticated and employ, e.g., an SQL-like syntax [9], or base on XML-QL [3]. The main focus of the existing services and evaluations regarding Profile Definition Languages forAlerting (PDLA) is the definition of the profile-query (cf. [2, 9]). That query part of a profile is matched against the event descriptions. Users can be interested in single (primitive) events or event combinations.Primitive events are described by event properties such as attribute value, time of event, or duration of a certain state of an object. Examples of query-profiles ar