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We would like to discuss with workshop participants the iTrails framework for pay-as-you-go information integration, which was recently presented at VLDB 2007 (M. A. V. Salles et al., 2007). iTrails allows users to provide mini-mappings on their data that sharply increase the quality of search results. The core idea is to extend the semantics of a standard graphical search engine such that the quality...
There are several pieces of information that can be utilized in order to improve the efficiency of similarity searches on high-dimensional data. The most commonly used information is the distribution of the data itself but the use of dimensional choice based on the information in the query as well as the parameters of the distribution can provide an effective improvement in the query processing speed...
Aircraft engine repair and overhaul (AERO) is an area of professional activity that draws heavily upon an engineer's knowledge. While engine maintenance typically follows a structured process, engine repairs are subject to unstructured processes. Such knowledge intensive professions benefit most from mobile knowledge management applications, but access of unstructured knowledge on mobile devices has...
In this environment each mobile peer has a local database that stores and manages a collection of reports (where each report is a product record, or a coupon), and all the local databases maintained by the mobile peers form a mobile e-commerce (or, more generally, a mobile P2P) database. Queries on this database are posed by potential customers, and they search for coupons and products pertaining...
This paper discusses our ongoing research efforts in regards to processing multi-scale queries in service-oriented environments. A multi-scale query is a query over traditional datasets in conjunction with streaming data and that may involve spatio-temporal aspects. In a service-oriented environment, classic and streaming data are made available and processed through services, which we refer to as...
Communication networks are vulnerable to emergencies both natural and manmade. Deployment of cost-effective, efficient and robust communications network for emergency situations is considered to be a vital problem. In this paper we propose the use of cognitive agents for post-disaster communications (CAP-C). Birth-death lifecycle of these mobile agents is also presented. We also presented a binary...
New collaborative applications relying on a MANET need multicast to perform efficient group communication. Application layer multicast is seen as a good alternative to the traditional network layer routing protocols because of its flexibility and ease of deployment. However, existing application layer multicast protocols for MANETs are not designed for collaborative scenarios. In this paper, we present...
Recent years have seen a proliferation of work on the Semantic Web, an initiative to enable intelligent agents to reason about and utilize World Wide Web content and services. Concurrently, the networking community has developed a concept of the knowledge plane, using artificial intelligence to reason about and manage network behavior. These two efforts have progressed independently despite potential...
The use of 802.11 long-distance links is a cost-effective means of providing wireless connectivity to rural areas. Although deployments in such settings are increasing, there are few empirical results reported on the performance of 802.11 over long distances. An empirical evaluation of 802.11 performance over long distances is a non-trivial task since it involves several variables such as the network...
Distributed denial of service (DDoS) attacks are today the most destabilizing factor in the global internet and there is a strong need for sophisticated solutions. We introduce a formal statistical framework and derive a Bayes optimal packet classifier from it. Our proposed practical algorithm "adaptive history-based IP filtering" (AHIF) mitigates DDoS attacks near the victim and outperforms...
We present a new access control model for XML Web-Services that provides users with two kinds of authorities: the authority to delegate their authorities to other users and the authority to create new authorities based on their own authorities. We developed this model by introducing capability- based access control to Web services. A capability consists of an object identifier and the list of permitted...
Service discovery and secure and safe service usage are essential elements in the deployment of home and personal networks. Because no system administrator is present, setup and daily operation of such a network has to be automated as much as possible with a high degree of user friendliness. To achieve this goal many systems sacrifice security and privacy such, that services can be discovered and...
Lately there has been a growing interest in the use of peer-to-peer technologies for deploying large-scale live media streaming systems over the Internet. In this paper we give a brief survey on the peer-to-peer streaming field and have also a closer look on selected applications. In practice, we analyse the selected peer-to-peer streaming systems (Octoshape, SopCast, TVAnts and TVU networks) and...
"Top K" queries reduce a query result to the most interesting or the most urgent items. In many cases, e.g., when the result size is unbounded due to duplicate key values, a "top" operation cannot be implemented using the standard algorithm based on an in-memory priority queue. The default alternative is a full sort. External merge sort admits multiple novel optimizations specific...
This paper introduces a novel keyword searching paradigm in relational databases (DBs), where the result of a search is a ranked set of object summaries (OSs). An OS summarizes all data held about a data subject (DS) in the database. More precisely, it is a tree with a tuple containing the keyword as a root and neighboring tuples as children. In contrast to traditional relational keyword search (R-KwS),...
Traditional data integration and analysis approaches tend to assume intimate familiarity with the structure, semantics, and capabilities of the available information sources before applicable tools can be used effectively. This assumption often does not hold in practice. We introduce dataspace profiling as the cardinal activity when beginning a project in an unfamiliar dataspace. Dataspace profiling...
We propose a new approach to the problem of schema matching in relational databases that merges the hybrid and composite approach of combining multiple individual matching techniques. In particular, we propose assigning individual matchers to two categories, "strong" matchers that provide a priori higher quality matches, and "weak" matchers that may be more sensitive to the inputs...
In ontology-based data access (OBDA), the aim is to use an ontology to mediate the access to data sources. We present a plug-in for the standard ontology editor Protege that allows users to model ontologies with mappings to data sources in order to perform OBDA. We argue that our plug-in, together with an OBDA-Enabled reasoner, allows users to build, test, and deploy OBDA Systems in academic or industrial...
If we consider a query involving multiple domains, such as "find all database conferences held within six months in locations whose seasonal average temperature is 28degC and for which a cheap travel solution exists", we note that (i) general- purpose search engines fail to answer multi-domain queries and (ii) specific search services may cover one of such domains, but no general integration...
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