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Web Information Systems and Technologies

9th International Conference, WEBIST 2013, Aachen, Germany, May 8-10, 2013, Revised Selected Papers

herausgegeben von: Karl-Heinz Krempels, Alexander Stocker

Verlag: Springer Berlin Heidelberg

Buchreihe : Lecture Notes in Business Information Processing

Enthalten in: Springer Professional "Wirtschaft+Technik" , Springer Professional "Technik" , Springer Professional "Wirtschaft"

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Über dieses Buch

This book contains the thoroughly refereed and revised best papers from the 9th International Conference on Web Information Systems and Technologies, WEBIST 2013, held in Aachen, Germany, in May 2013, organized by the Institute for Systems and Technologies of Information, Control and Communication (INSTICC), and co-organized by the RWTH Aachen University.

The 15 papers presented in this book were carefully reviewed and selected from 143 submissions. The papers were selected from those with the best reviews also taking into account the quality of their presentation at the conference. The papers are grouped into parts on Internet technology, Web interfaces and applications, society, e-business and e-government, Web intelligence, and mobile information systems.

Inhaltsverzeichnis

Frontmatter

Internet Technology

Frontmatter

Networked XML Compression by Encoding Pre-order Traversals

Abstract

The advantages of the eXtensible Markup Language, XML, come at a cost, especially for huge datasets or when used on small mobile devices. Several known XML-conscious compressors used in real time environments compress data during data streaming. This paper presents a study of new real time algorithms that exploit local structural redundancies of pre-order traversals of an XML tree. These algorithms focus on reducing the overhead of streaming data while maintaining load balancing between the sender and receiver. Our algorithms have similar or better performance than existing algorithms, while emphasizing low memory and processing overheads.

Tyler Corbin, Tomasz Müldner, Jan Krzysztof Miziołek

Generating XACML Enforcement Policies for Role-Based Access Control of XML Documents

Abstract

Ensuring the security of electronic data has morphed into one of the most important requirements in domains such as health care, where the eXtensible Markup Language (XML) has been leveraged via standards such as the Health Level 7’s Clinical Document Architecture and the Continuity of Care Record. These standards dictate a need for approaches to secure XML schemas and documents. In this paper, we present a secure information engineering method that is capable of generating eXtensible Access Control Markup Language (XACML) enforcement policies, defined in a role-based access control model (RBAC), that target XML schemas and their instances, allowing instances to be customized for users depending on their roles. To achieve this goal, we extend the Unified Modeling Language (UML) with two new diagrams: the XML Schema Class Diagram, which defines the structure of an XML document in UML style; and, the XML Role-Slice Diagram, which defines roles and associated privileges at a granular access control level. We utilize a personal health assistant mobile application for medication and chronic disease management to demonstrate the enforcement component of our work.

Alberto De la Rosa Algarín, Timoteus B. Ziminski, Steven A. Demurjian, Yaira K. Rivera Sánchez, Robert Kuykendall

Engineering Flexible Service-Oriented Transactions

Abstract

The traditional ACID properties for transactions are not always appropriate in service-oriented environments. Instead, it is often preferable to “relax” the transactional guarantees, reducing isolation or atomicity to ensure acceptable performance at a reasonable cost. Existing standards require providers to constantly offer a fixed level of transaction support to each client that requests a particular service. We present a mechanism that allows providers to dynamically alter the level of transaction support offered on a per-service-call basis. Further, we engineer a cost-based model, based on \(\pi t\)-calculus, that allows clients to automatically reason about workflows consisting of service requests with various levels of transaction support. The viability of this scheme is tested with a Web Services transactions simulator, with results indicating potential benefits for both clients and service providers.

David Paul, Frans Henskens

HTML5 Agents: Mobile Agents for the Web

Abstract

We argue that the modern Web infrastructure with HTML5 as such can be an agent platform and mobile agents could be developed in similar way as Web applications. For us the agents can also be end-user applications that the user can send to a server so that the state is preserved and the execution can continue. The user can later fetch the agent to the same client device or to another device. In addition to the mobile agent use cases, the concept also allows users to continue their work later on another device or even allows other users to continue execution in their own devices. The paper presents the overall concept and architecture of HTML5 agents, a number of use cases, the proof-of-concept implementation, and a list of example applications.

Kari Systä, Tommi Mikkonen, Laura Järvenpää

Watermarking Digital Images in the Frequency Domain: Performance and Attack Issues

Abstract

In this work we propose an efficient model for watermarking images that are intended for uploading on the web under intellectual property protection. Headed to this direction, we recently suggested a way in which an integer number \(w\) which being transformed into a self-inverting permutation, can be represented in a two dimensional (2D) object and thus, since images are 2D structures, we propose a watermarking algorithm that embeds marks on them using the 2D representation of \(w\) in the frequency domain. In particular, we propose a watermarking technique that uses the 2D representation of self-inverting permutations and utilizes marking at specific areas thanks to partial modifications of the image’s Discrete Fourier Transform (DFT). Those modifications are made on the magnitude of specific frequency bands and they are the least possible additive information ensuring robustness and imperceptiveness. We have experimentally evaluated our algorithms using various images of different characteristics under JPEG compression, Gaussian noise addition, and geometric transformations. The experimental results show an improvement in comparison to the previously obtained results and they also depict the validity of our proposed codec algorithms.

Maria Chroni, Angelos Fylakis, Stavros D. Nikolopoulos

Web Interfaces and Applications

Frontmatter

Towards a Web of Semantic Tags

Abstract

Folksonomies are widely used to classify content on the Web. However, plain text annotations hardly fit the vision of the Semantics Web, where an unambiguous understanding of the data by both user and machine is key. Ontologies underpinning the Web help to resolve the ambiguity problem, but a.o. the absence of a detailed world ontology still puts end-user tagging in the front seat for basic content classification. In this paper, we propose semantic tags to bridge the gap between plain text keywords and ontologies. Sematags define aliases (synonyms) and isas (hypernyms) to better cope with the issues traditional tags suffer from. We illustrate how sematags can be defined from scratch or extracted from existing lexicons and knowledge bases. To evaluate our approach, we composed sematags from Wikipedia concepts and used those to semi-automatically tag photos on Flickr.

Geert Vanderhulst, Lieven Trappeniers

Web Service Discovery and Execution Using a Dialog-Based Approach

Abstract

Several Semantic Web techniques applied in Service-oriented architectures enable explicit representation and reasoning on service operations. Those techniques applied to the automatic discovery, selection and execution of services are promising but still too complex to allow a large-scale adoption. Consequently, the most widespread approach for upgrading existing services to a semantic level is the usage of traditional software engineering practices, resulting in complex and non-intuitive interfaces in some cases. We propose an approach to leverage the service discovery, selection and execution processes for Web services without semantic annotations, using only the WSDL descriptor as a source. In order to do so, we first identify candidates based on linguistic cues extracted from the Web service descriptor. The generated proof-of-concept allows users to select and execute service operations through a personal assistant using restricted requests in natural language.

Márcio Fuckner, Jean-Paul Barthès, Edson Emilio Scalabrin

Comparison of Mobile Web Frameworks

Abstract

When developing mobile applications for more than one platform, developers often use cross-platform development approaches based on Web technologies such as mobile Web apps instead of native development. While the single, platform-independent source code reduces development effort, Web apps still need to be optimized for mobile particularities such as limited screen size and touch-based interaction. Developers may choose from a variety of mobile Web frameworks that support them in this regard, each with different strengths and weaknesses. In this paper, we intend to guide the decision of developers for a Web framework based on a set of criteria expected from high-quality frameworks.

Henning Heitkötter, Tim A. Majchrzak, Benjamin Ruland, Till Weber

Improving Search Engines’ Document Ranking Employing Semantics and an Inference Network

Abstract

The users search mainly diverse information from several topics and their needs are difficult to be satisfied from the techniques currently employed in commercial search engines and without intervention from the user. In this paper, a novel framework is presented for performing re-ranking in the results of a search engine based on feedback from the user. The proposed scheme combines smoothly techniques from the area of Inference Networks and data from semantic knowledge bases. The novelty lies in the construction of a probabilistic network for each query which takes as input the belief of the user to each result (initially, all are equivalent) and produces as output a new ranking for the search results. We have constructed an implemented prototype that supports different Web search engines and it can be extended to support any search engine. Finally extensive experiments were performed using the proposed methods depicting the improvement of the ranking of the search engines results.

Christos Makris, Yannis Plegas, Giannis Tzimas, Emmanouil Viennas

Category-Based YouTube Request Pattern Characterization

Abstract

Media content distribution systems make extensive use of computational resources, such as disk and network bandwidth. The use of these resources is proportional to the relative popularity of the objects and their level of replication over time. Therefore, understanding request popularity over time can inform system design decisions. As well, advertisers can target popular objects to maximize their impact.

Workload characterization is especially challenging with user-generated content, such as in YouTube, where popularity is hard to predict a priori and content is uploaded at a very fast rate. In this paper, we consider category as a distinguishing feature of a video and perform an extensive analysis of a snapshot of videos uploaded over two 24-h periods. Our results show significant differences between categories in the first 149 days of the videos’ lifetimes. The lifespan of videos, relative popularity and time to reach peak popularity clearly differentiate between news/sports and music/film. Predicting popularity is a challenging task that requires sophisticated techniques (e.g. time-series clustering). From our analysis, we develop a workload generator that can be used to evaluate caching, distribution and advertising policies. This workload generator matches the empirical data on a number of statistical measurements.

Shaiful Alam Chowdhury, Dwight Makaroff

Society, e-Business and e-Government

Frontmatter

Enhancing the Modularity and Applicability of Web-Based Signature-Verification Tools

Abstract

Electronic signature are an important concept and crucial tool for security-critical applications. Employing the full potential of electronic signatures requires the availability of appropriate signature-verification tools. Today, a plethora of different signature-verification tools exist that allow users to verify electronically signed files and documents. Unfortunately, most of these tools have been designed for a special use case and lack support for various fields of application. This renders the development of applications based on electronic signatures difficult and reduces usability for end users. To overcome this issue, we propose an improved architecture for signature-verification tools. This architecture ensures flexibility and an easy extensibility by following a plug-in-based approach. The applicability and practicability of the proposed architecture has been assessed by means of a concrete implementation. This implementation demonstrates the proposed architecture’s capability to meet requirements of various different application scenarios and use cases. This way, the proposed architecture and the developed implementation that relies on this architecture contribute to the security, usability, and efficiency of present and future electronic signature-based applications.

Thomas Lenz, Klaus Stranacher, Thomas Zefferer

Status Quo and Best Practices of App Development in Regional Companies

Abstract

Only a few years after their advent, smartphones and tablets are now used routinely by many people. While this has been bolstered by the fast innovation cycles of the hardware, mobile devices become versatile due to the applications developed for them. These apps are increasingly used for business purposes. In a research project we investigated whether apps are interesting for all businesses, how and for which activities they plan to use apps, and what kinds of challenges and problems they perceive. To this end, we conducted an interview-based survey with regional companies. Thoroughly analyzing the transcripts enabled us to draw conclusions on the status quo of apps. In this article we present the results from the project, including a set of early best practices. We also discuss our findings to derive directions for future research.

Tim A. Majchrzak, Henning Heitkötter

Web Intelligence

Frontmatter

Vector Space Models for the Classification of Short Messages on Social Network Services

Abstract

In this chapter we review vector space models to propose a new one based on the Jensen-Shannon divergence with the goal of classifying ignored short messages on a social network service. We assume that ignored messages are those published ones that were not interacted with. Our goal then is to attempt to classify messages to be published as ignored to discard them from a set messages that can be used by a recommender system. To evaluate our model, we conduct experiments comparing different models on a Twitter dataset with more than 13,000 Twitter accounts. Results show that our best model tested obtained an average accuracy of 0.77, compared to 0.74 from a model from the literature. Similarly, this method obtained an average precision of 0.74 compared to 0.58 from the second best performing model.

Ricardo Lage, Peter Dolog, Martin Leginus

FactRunner: A New System for NLP-Based Information Extraction from Wikipedia

Abstract

Wikipedia is playing an increasing role as a source of human-readable knowledge, because it contains an enormous amount of high quality information written by human authors. Finding a relevant piece of information in this huge collection of natural language text is often a time-consuming process, as a keyword-based search interface is the main method for querying. Therefore, an iterative process to explore the document collection to find the information of interest is required. In this paper, we present an approach to extract structured information from unstructured documents to enable structured queries. Information Extraction (IE) systems have been proposed for this tasks, but due to the complexity of natural language, they often produce unsatisfying results.

As Wikipedia contains, in addition to the plain natural language text, links between documents and other metadata, we propose an approach which exploits this information to extract more accurate structured information. Our proposed system FactRunner focusses on extracting structured information from sentences containing such links, because the links may indicate more accurate information than other sentences. We evaluated our system with a subset of documents from Wikipedia and compared the results with another existing system. The results show that a natural language parser combined with Wikipedia markup can be exploited for extracting facts in form of triple statements with a high accuracy.

Rhio Sutoyo, Christoph Quix, Fisnik Kastrati

Mobile Information Systems

Frontmatter

Context and Activity Recognition for Personalized Mobile Recommendations

Abstract

Through the use of mobile devices, contextual information about users can be derived to use as an additional information source for traditional recommendation algorithms. This paper presents a framework for detecting the context and activity of users by analyzing sensor data of a mobile device. The recognized activity and context serves as input for a recommender system, which is built on top of the framework. Through context-aware recommendations, users receive a personalized content offer, consisting of relevant information such as points-of-interest, train schedules, and touristic info. An evaluation of the recommender system and the underlying context-recognition framework demonstrates the impact of the response times of external information providers. The data traffic on the mobile device required for the recommendations shows to be limited. A user evaluation confirms the usability and attractiveness of the recommender. The recommendations are experienced as effective and useful for discovering new venues and relevant information.

Toon De Pessemier, Simon Dooms, Kris Vanhecke, Bart Matté, Ewout Meyns, Luc Martens

Backmatter

Titel: Web Information Systems and Technologies
herausgegeben von: Karl-Heinz Krempels
Alexander Stocker
Verlag: Springer Berlin Heidelberg
Electronic ISBN: 978-3-662-44300-2
Print ISBN: 978-3-662-44299-9
DOI: https://doi.org/10.1007/978-3-662-44300-2