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This paper presents a novel method of designing selected aspects of messaging-based integration solutions. The method uses constraint programming to find appropriate communication channels, components΄ deployment parameters and integration services in order to create a solution that meets specified functional and non-functional requirements. The method has been evaluated using a prototype implementation and compared to authors΄ earlier work that used action-based planning techniques to reach similar goals. [ABSTRACT FROM AUTHOR]

SPEM is metamodel based standard used to define software and systems development processes and their components. Unfortunately, its architecture is semiformal, thus it is not possible to make and to verify created language statements with formal techniques such as the consistency or satisfiability verification. Recently, the combination of MDA and the Semantic Web, in which data processing is concerned with regard to their semantics, become the leading subject in this direction. In this work we present a SPEM transformation to the Semantic Web technical space and consequently we propose its utilization that is an ontology based approach to software project enactment with a supplier. We discuss its usage scenarios that are a verification of a set of SPEM methods and processes with ontology, and a project plan generation and verification with a set of SPEM method plugin ontologies. Additionally we present examples that addresses to the proposed usage scenarios. [ABSTRACT FROM AUTHOR]

This paper presents a parallel artificial immune system designed for graph coloring. The algorithm is based on the clonal selection principle. Each processor operates on its own pool of antibodies and a migration mechanism is used to allow processors to exchange information. Experimental results show that migration improves the performance of the algorithm. The experiments were performed using a high performance cluster on a set of well-established graph instances available on the Web. [ABSTRACT FROM AUTHOR]

We introduce the notion of net-slice to describe a subnet of a marked Petri net Σ that approximates Σ's temporal behaviour with respect to a set of places P. We consider slices Σ′ whose set of places comprises the places referred to by a CTL* formula φ. If Σ is fair w.r.t. the transitions of a slice, Σ ⊧ φ can be verified and falsified by examining the slice, given φ is a CTL* formula built without using the next-time operator. Verification of LTL$_{\textrm{-\tiny{X}}}$ formulas is thus possible under these very weak fairness assumptions, though LTL formulas using next-time can be falsified. [ABSTRACT FROM AUTHOR]

The need for data privacy motivates the development of new methods that allow to protect data minimizing the disclosure risk without losing valuable statistical information. In this paper, we propose a new protection method for numerical data called Ordered Neural Networks (ONN). ONN presents a new way to protect data based on the use of Artificial Neural Networks (ANNs). The main contribution of ONN is a new strategy for preprocessing data so that the ANNs are not capable of accurately learning the original data set. Using the results obtained by the ANNs, ONN generates a new data set similar to the original one without disclosing the real sensible values. We compare our method to the best methods presented in the literature, using data provided by the US Census Bureau. Our experiments show that ONN outperforms the previous methods proposed in the literature, proving that the use of ANNs is convenient to protect the data efficiently without losing the statistical properties of the set. [ABSTRACT FROM AUTHOR]

Growing need for information retrieval, information processing, and the associated need for navigation in existing information spaces resulted in several approaches that aim to improve efficiency of the respective user tasks. However, problems related to user navigation and orientation in large open information spaces still persist possibly due to increasing demands and the imperfections of individual approaches. We propose an integrated search and navigation solution that takes advantage of the faceted browsing paradigm and visual navigation in graphs both extended with support for automatic personalization based on user context also taking advantage of a user's social network. The proposed solution is primarily evaluated in the domain of scientific publications, i.e. digital libraries, with possible extensions to other application domains. [ABSTRACT FROM AUTHOR]

Over the last decade, Web and multimedia data have grown at a staggering rate. Users of new media now have great expectations of what they can see on the Web. In addition, most information retrieval systems, including Web search engines, use similarity ranking algorithms based on a vector space model to find relevant information in response to a user's request. However, the retrieved information is frequently irrelevant, because most of the current information systems employ index terms or other techniques that are variants of term frequency. This paper proposed a new approach, named "the dynamic multimedia presentations with a Generality Model," to offer a customized multi-modal presentation for an intended audience. Moreover, we proposed a new criterion, "generality," that provides an additional basis on which to rank retrieved documents. To support multi-modal presentation, our proposed story model created story structures that can be dynamically instantiated for different user requests from various multi-modal elements. The generality is a level of abstraction to retrieve results based on desired generality appropriate for a user's knowledge and interests. We compared traditional web news search functions and our story model by using usability test. The result shows that our multimedia presentation methodology is significantly better than the current search functions. We also compared our generality quantification algorithm with human judges' weighting of values to show that the developed algorithm is significantly correlated. [ABSTRACT FROM AUTHOR]

In this paper was proposed a method for the description of web pages using web patterns. We will explain what we mean by the term "web pattern". We will present a taxonomy web patterns and a description of some their types. In the description of web patterns we will focus on properties which are useful for automatic detection on web pages. As a result of the detection we get a description of a web page using found web patterns. The description can be used for reordering and clustering of a web page set. [ABSTRACT FROM AUTHOR]

Contemporary XML documents can be tens of megabytes long, and reducing their size, thus allowing to transfer them faster, poses a significant advantage for their users. In this paper, we describe a new XML compression scheme which outperforms the previous state-of-the-art algorithm, SCMPPM, by over 9% on average in compression ratio, having the practical feature of streamlined decompression and being almost twice faster in the decompression. Applying the scheme can significantly reduce transmission time/bandwidth usage for XML documents published on the Web. The proposed scheme is based on a semi-dynamic dictionary of the most frequent words in the document (both in the annotation and contents), automatic detection and compact encoding of numbers and specific patterns (like dates or IP addresses), and a back-end PPM coding variant tailored to efficiently handle long matching sequences. Moreover, we show that the compression ratio can be improved by additional 9% for the price of a significant slow-down. [ABSTRACT FROM AUTHOR]

XBW [10] is modular program for lossless compression that enables testing various combinations of algorithms. We obtained best results with XML parser creating dictionary of syllables or words combined with Burrows-Wheeler transform - hence the name XBW. The motivation for creating parser that handles non-valid XML and HTML files, has been system EGOTHOR [5] for full-text searching. On files of size approximately 20MB, formed by hundreds of web pages, we achieved twice the compression ratio of bzip2 while running only twice as long. For smaller files, XBW has very good results, compared with other programs, especially for languages with rich morphology such as Slovak or German. For any big textual files, our program has good balance of compression and run time. Program XBW enables use of parser and coder with any implemented algorithm for compression. We have implemented Burrows-Wheeler transform which together with MTF and RLE forms block compression, dictionary methods LZC and LZSS, and finally statistical method PPM. Coder offers choice of Huffman and arithmetic coding. [ABSTRACT FROM AUTHOR]

The development of structure analysis that constitutes the core part of social network analysis is continuously supported by the rapid expansion of different kinds of social networks available in the Internet. The network analyzed in this paper is built based on the email communication between people. Exploiting the data about this communication some personal social features can be discovered, including personal position that means individual importance within the community. The evaluation of position of an individual is crucial for user ranking and extraction of key network members. The new method of personal importance analysis is presented in the paper. It takes into account the strength of relationships between network members, its dynamic as well as personal position of the nearest neighbours. The requirements for the commitment function that reflects the strength of the relationship are also specified. In order to validate the proposed method, the dataset containing Enron emails is utilized; first to build the virtual social network and afterwards to assess the position of the network members. [ABSTRACT FROM AUTHOR]

In this paper we present a communicational proof-of-work - a new tool that can be used, among others, for filtering messages and limiting spam. Our idea can be regarded as an analogue of regular proofs-of-work introduced by Dwork and Naor. The idea presented in our paper is as follows: the prover has to provide a convincing evidence that he had communicated with other, randomly chosen entity. This approach is essentially different from previous proofs-of-work, because fulfilling this requirement does not depend on resources owned by the prover (e.g. sender) only. Thanks to this, even if the adversary (e.g. spammer) has an access to much more efficient computers, he does not have any important advantage over regular, honest users of the system. We also demonstrate some other applications of the presented idea as well as some extensions based on its combination with regular proofs-of-work. Together with algorithms we also briefly describe a proof of our concept i.e. working implementation. We present some experimental data and statistics obtained during tests of our application. [ABSTRACT FROM AUTHOR]