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Process mining combines model-based process analysis with data-driven analysis techniques. The role of process mining is to extract knowledge and gain insights from event logs. Most existing techniques focus on process discovery (the automated extraction of process models) and conformance checking (aligning observed and modeled behavior). Relatively little research has been performed on the analysis of business process performance. Cooperative business processes often exhibit a high degree of variability and depend on many factors. Finding root causes for inefficiencies such as delays and long waiting times in such flexible processes remains an interesting challenge. This paper introduces a novel approach to analyze key process performance indicators by considering the process context. A generic context-aware analysis framework is presented that analyzes performance characteristics from multiple perspectives. A statistical approach is then utilized to evaluate and find significant differences in the results. Insights obtained can be used for finding high-impact points for optimization, prediction, and monitoring. The practical relevance of the approach is shown in a case study using real-life data.

In the area of business process modelling, declarative notations have been proposed as alternatives to notations that follow the dominant, imperative paradigm. Yet, the choice between an imperative or declarative style of modelling is not always easy to make. Instead, a mixture of these styles is sometimes preferable. This observation has underpinned recent calls for so-called hybrid process modelling notations. In this paper, we present a formal semantics for these. In our proposal, a hybrid process model is hierarchical, where each of its sub-processes may be specified in either an imperative or declarative fashion. The semantics we provide will allow modelling communities to build on the benefits of existing imperative and declarative modelling notations, instead of spending their energy on inventing new ones.

International audience; This double volumes LNCS 11229-11230 constitutes the refereed proceedings of the Confederated International Conferences: Cooperative Information Systems, CoopIS 2018, Ontologies, Databases, and Applications of Semantics, ODBASE 2018, and Cloud and Trusted Computing, C&TC, held as part of OTM 2018 in October 2018 in Valletta, Malta. The 64 full papers presented together with 22 short papers were carefully reviewed and selected from 173 submissions. The OTM program every year covers data and Web semantics, distributed objects, Web services, databases, informationsystems, enterprise workflow and collaboration, ubiquity, interoperability, mobility, grid and high-performance computing.

Process discovery algorithms typically aim at discovering process models from event logs that best describe the recorded behavior. Often, the quality of a process discovery algorithm is measured by quantifying to what extent the resulting model can reproduce the behavior in the log, i.e. replay fitness. At the same time, there are many other metrics that compare a model with recorded behavior in terms of the precision of the model and the extent to which the model generalizes the behavior in the log. Furthermore, several metrics exist to measure the complexity of a model irrespective of the log. In this paper, we show that existing process discovery algorithms typically consider at most two out of the four main quality dimensions: replay fitness, precision, generalization and simplicity. Moreover, existing approaches can not steer the discovery process based on user-defined weights for the four quality dimensions. This paper also presents the ETM algorithm which allows the user to seamlessly steer the discovery process based on preferences with respect to the four quality dimensions. We show that all dimensions are important for process discovery. However, it only makes sense to consider precision, generalization and simplicity if the replay fitness is acceptable.

The entailment of an RDF graph under the RDF Schema standard can easily become too costly to compute and maintain. It is often more desirable to compute on-demand whether a triple exists in the entailment. This is a non-trivial task likely to incur I/O costs, since RDF graphs are often too large to fit in internal memory. As disk I/O is expensive in terms of time, I/O costs should be minimized to achieve better performance. We investigate three physical indexing methods for RDF storage on disk, comparing them using the state of the art RDF Schema entailment algorithm of Muñoz et al. In particular, the I/O behavior during entailment checking over these graph representations is studied. Extensive empirical analysis shows that an enhanced version of the state of the art indexing method, which we propose here, yields in general the best I/O performance.

In this paper we will address the conceptual schema design procedure (CSDP) in fact-based modeling. We will focus on the modeling procedure of 'cook-book' for deriving set-comparison constraints. We will give an algorithm that can be applied by an analyst in an analyst-user dialogue in which all set-comparison constraints can be derived as a result of the acceptance or rejection of real-life user examples by the domain expert.

We present a new approach to anomaly-based network intrusion detection for web applications. This approach is based on dividing the input parameters of the monitored web application in two groups: the "regular" and the "irregular" ones, and applying a new method for anomaly detection on the "regular" ones based on the inference of a regular language. We support our proposal by realizing Sphinx, an anomaly-based intrusion detection system based on it. Thorough benchmarks show that Sphinx performs better than current state-of-the-art systems, both in terms of false positives/false negatives as well as needing a shorter training period.

Two major problems in constructing data federations (for example, data warehouses and database federations) concern achieving and maintaining consistency and a uniform representation of the data on the global level of the federation. The first step in creating uniform representations of data is known as data extraction, whereas data reconciliation is concerned with resolving data inconsistencies. Our approach to constructing a global conceptual schema as the result of integrating a collection of (semantically) heterogeneous component schemas is based on the concept of exact views. We show that a global schema constructed in terms of exact views integrates component schemas in such a way that the global schema is populated by exactly those instances allowed by the local schemas (and in special cases, also the other way around). In this sense, the global schema is equivalent to the set of component schemas from which the global schema is derived. This paper describes a modeling framework for data federations based on the Object-Role Modeling (ORM) approach. In particular, we show that we can represent exact views within ORM, providing the means to resolve in a combined setting data extraction and reconciliation problems on the global level of the federation.

This paper proposes an extension to the Object-Role Modeling approach to support formal declaration of dynamic rules Dynamic rules differ from static rules by pertaining to properties of state transitions, rather than to the states themselves In this paper, application of dynamic rules is restricted to so-called single-step transactions, with an old state (the input of the transaction) and a new state (the direct result of that transaction) Such restricted rules are easier to formulate (and enforce) than a constraint applying historically over all possible states In our approach, dynamic rules specify an elementary transaction type indicating which kind of object or fact is being added, deleted or updated, and (optionally) pre-conditions relevant to the transaction, followed by a condition stating the properties of the new state, including the relation between the new state and the old state These dynamic rules are formulated in a syntax designed to be easily validated by non-technical domain experts.

The emergence of Semantic Web (SW) and the related technologies promise to make the web a meaningful experience. Yet, high level modeling, design and querying techniques proves to be a challenging task for organizations that are hoping utilize the SW paradigm for their industrial applications, which are still using traditional database techniques. To address such an issue, in this paper, we propose a view model for the SW (SW-View), to SW-enable traditional solutions. First we outline the view model, its properties and some modeling issues, followed by some discussions on modeling such views (at the conceptual level). We also provide a brief discussion on how this view model is utilized in the design and construction of materialized ontology views to support extraction of sub-ontologies.

Information systems are facing conflicting requirements. On the one hand, systems need to be adaptive and self-managing to deal with rapidly changing circumstances. On the other hand, legislation such as the Sarbanes-Oxley Act, is putting increasing demands on monitoring activities and processes. As processes and systems become more flexible, both the need for, and the complexity of monitoring increases. Our earlier work on process mining has primarily focused on process discovery, i.e., automatically constructing models describing knowledge extracted from event logs. In this paper, we focus on a different problem complementing process discovery. Given an event log and some property, we want to verify whether the property holds. For this purpose we have developed a new language based on Linear Temporal Logic (LTL) and we combine this with a standard XML format to store event logs. Given an event log and an LTL property, our LTL Checker verifies whether the observed behavior matches the (un)expected/(un)desirable behavior.

It is well accepted that different types of distributed architectures require different levels of coupling. For example, in client-server and three-tier architectures the application components are generally tightly coupled between them and with the underlying communication middleware. Meanwhile, in off-line transaction processing, grid computing and mobile application architectures, the degree of coupling between application components and with the underlying middleware needs to be minimised along different dimensions. In the literature, terms such as synchronous, asynchronous, blocking, non-blocking, directed, and non-directed are generally used to refer to the degree of coupling required by a given architecture or provided by a given middleware. However, these terms are used with various connotations by different authors and middleware vendors. And while several informal definitions of these terms have been provided, there is a lack of an overarching framework with a formal grounding upon which software architects can rely to unambiguously communicate architectural requirements with respect to coupling. This paper addresses this gap by: (i) identifying and formally defining three dimensions of coupling; (ii) relating these dimensions to existing communication middleware; and (iii) proposing notational elements for representing coupling configurations. The identified dimensions provide the basis for a classification of middleware which can be used as a selection instrument.

We report on the development of a prototype dialogue game for FCO-IM. Dialogue games are systems for executing controlled conversations. As part of an ongoing effort to analyze and support collaborative modeling processes by means of dialogue games, we created a dialogue game prototype for essential parts of the FCO-IM modeling process. The project was exploratory in nature, but results suggest that eventually it should be possible to develop dialogue games that could effectively support fact-based conceptual modeling efforts. In addition, work on such games enhances our insights in the FCO-IM modeling process, and leads to improvements and extensions of its operational guidelines.

Metadata management is a key issue in intelligent Web-based environments. It plays an important role in a wide spectrum of areas, ranging from semantic explication, information handling, knowledge management, multimedia processing to personalized service delivery. As a result, security issues around metadata management needs to be addressed in order to build trust and confidence to ambient environments. The aim of this paper is to bring together the worlds of security and XML-formatted metadata management in such a way that, on the one hand the requirement on secure metadata management is satisfied, while on the other other hand the efficiency on metadata processing can still be guaranteed. To this end, we develop an effective approach to enable efficient search on encrypted XML metadata. The basic idea is to augment encrypted XML metadata with encodings which characterize the topology and content of every tree-structured XML metadata, and then filter out candidate data for decryption and query execution by examining query conditions against these encodings. We describe a generic framework consisting of three phases, namely, query preparation, query pre-processing and query execution, to implement the proposed search strategy.

In this paper we argue that the effort within the context of Semantic Web research, such as RDF and DAML-S. will allow for better knowledge representation and engineering of educational systems and easier integration of e-learning with other business processes. We also argue that existing educational standards, such as SCORM and LOM could be mapped to those technologies, providing for more efficient automation of processes like educational resource annotation, and intelligent accessibility management. In this way we can use a successful combination of the technical advances outside of educational context and the existing educational standards, and allow for easier interoperability. To illustrate these issues and a solution approach we present the OntoAIMS educational environment.

During the development of theoretical frameworks researchers often graphically represent formal textual notations as part of a developed theory. This may lead to enrichments and new insights regarding a theory. A possibility for graphical representation of formalisms is the utilization of modeling languages such as ORM. This paper deals with the technique of visualizing formalisms by using ORM models and shows the advantages of graphically representing a formal theoretical framework. An application of the approach that has already been successfully practised is elaborated. This application concerns a theoretical framework consisting of knowledge intensive task properties and shows how the approach to visualize formalisms with ORM can be materialized.

This paper presents the realisation, using a Service Oriented Architecture, of an approach for dynamic flexibility and evolution in workflows through the support of flexible work practices, based not on proprietary frameworks, but on accepted ideas of how people actually work. A set of principles have been derived from a sound theoretical base and applied to the development of worklets, an extensible repertoire of self-contained sub-processes aligned to each task, from which a dynamic runtime selection is made depending on the context of the particular work instance. An erratum to this chapter can be found at http://dx.doi.org/10.1007/11914853_71.

Process mining techniques relate observed behavior to modeled behavior, e.g., the automatic discovery of a Petri net based on an event log. Process mining is not limited to process discovery and also includes conformance checking. Conformance checking techniques are used for evaluating the quality of discovered process models and to diagnose deviations from some normative model (e.g., to check compliance). Existing conformance checking approaches typically focus on the control-flow, thus being unable to diagnose deviations concerning data. This paper proposes a technique to check the conformance of data-aware process models. We use so-called Petri nets with Data to model data variables, guards, and read/write actions. Data-aware conformance checking problem may be very time consuming and sometimes even intractable when there are many transitions and data variables. Therefore, we propose a technique to decompose large data-aware conformance checking problems into smaller problems that can be solved more efficiently. We provide a general correctness result showing that decomposition does not influence the outcome of conformance checking. The approach is supported through ProM plug-ins and experimental results show significant performance improvements. Experiments have also been conducted with a real-life case study, thus showing that the approach is also relevant in real business settings. Keywords: ProcessMining; Conformance Checking; Divide-and-Conquer Techniques; Multi-Perspective Process Modelling

New application domains in data-processing environments pose new requirements on the methodologies, techniques and tools used to design them. The applications’ semantics should be fully represented at an increasingly high level, and the representation should be subject to rigorous validation and verification. We present a semantic representation framework (including the language, methods and tools) for design of data-processing applications. The new features of the framework include a small number of precisely defined domain-independent concepts, high-level possibilities for describing behavioural semantics (methods and constraints) and the validation and verification tools included in the framework. We present examples of the use of the framework, including the use of its tools.

International audience; Data integration systems off er uniform access to a set of autonomous and heterogeneous data sources. An important task in setting up a data integration system is to match the attributes of the source schemas. In this paper, we propose a data integration system which uses the knowledge implied within functional dependencies for matching the source schemas. We build our system on a probabilistic data model to capture the uncertainty arising during the matching process. Our performance validation con rms the importance of functional dependencies and also using a probabilistic data model in improving the quality of schema matching. Our experimental results show significant performance gain compared to the baseline approaches. They also show that our system scales well.

The service-oriented architecture paradigm has gained attention in the past years, because it promised to lay the foundation for agility, in the sense that it would enable companies to deliver new and more flexible business processes to improve customer satisfaction [1, 2, 3]. In the service-oriented architecture (soa) paradigm, a service requesting organization (sro) basically outsources one or more organizational activities or even complete business processes to one or more service delivering organizations (sdos). The way this is done in a traditional way, is that the sro ‘outsources’ a given business service to a ‘third-party’ sdo for a relative long period of time (3 months, a year). In an agile environment, the reconfigurable resources might face a life-span of a few days or even a few hours, in principle reconfiguration of business services can take place on a run-time time-scale, in the sense that for each new transaction a possibly different sdo must be configured into the value chain. The application of the service-oriented paradigm, therefore, allows the dynamic composition of business functionality by using the world-wide web [3, 4].

Service-oriented computing (SOC) allows organizations to tailor their business processes, in such a way that efficiency and effectiveness goals will be achieved by outsourcing (parts of) business processes to external (web-based) service-providers. In order to find the computing service-providers that provide the organizations with the biggest benefits, it is paramount that the service-requesting organization (SRO) has a precise description of the service it wants to have delivered by the service delivering organization (SDO). In this paper we will illustrate how enterprises that play the SDO and SRO roles can be conceptually integrated by creating conceptual models that share the definitions of the business processes within the service oriented architecture (SOA) framework.

In this paper the so-called Event Cube is introduced, a multidimensional data structure that can hold information about all business dimensions. Like the data cubes of online analytic processing (OLAP) systems, the Event Cube can be used to improve the business analysis quality by providing immediate results under different levels of abstraction. An exploratory analysis of the application of process mining on multidimensional process data is the focus of this paper. The feasibility and potential of this approach is demonstrated through some practical examples.

Product Based Workflow Design (PBWD) is one of the few scientific methodologies for the (re)design of workflow processes. It is based on an analysis of the product that is produced in the workflow process and derives a process model from the product structure. Until now this derivation has been a manual task and is therefore a time-consuming and error-prone exercise. Automatic support would enhance the use of the PBWD methodology. In this paper we propose several algorithms to automatically generate process models from a product structure and we present a software tool (implemented in ProM) to support this. Finally, the properties of the resulting process models are analysed and discussed.

Recent years have seen an increased uptake of business process management technology in various industries. This has resulted in organizations trying to manage large collections of business process models. One of the challenges facing these organizations concerns the retrieval of models from large business process model repositories. As process model repositories may be large, query evaluation may be time consuming. Hence, we investigate the use of indexes to speed up this evaluation process. Experiments are conducted to demonstrate that our proposal achieves a significant reduction in query evaluation time.

Recently, the OMG has been working on developing a new standard for a Business Process Model and Notation (BPMN). This standard development has resulted in documents that contain the latest approved version of a standard or a standard proposal that can be ammended. Such a standard document also serves as a specification for BPMN modeling tool. In this paper we show how a fact-based approach can improve the completeness and maintenance of such a specification.

Reference process models are templates for common processes run by many corporations. However, the individual needs among organizations on the execution of these processes usually vary. A process model can address these variations through control-flow choices. Thus, it can integrate the different process variants into one model. Through configuration parameters, a configurable reference models enables corporations to derive their individual process variant from such an integrated model. While this simplifies the adaptation process for the reference model user, the construction of a configurable model integrating several process variants is far more complex than the creation of a traditional reference model depicting a single best-practice variant. In this paper we therefore recommend the use of process mining techniques on log files of existing, well-running IT systems to help the reference model provider in creating such integrated process models. Afterwards, the same log files are used to derive suggestions for common configurations that can serve as starting points for individual configurations.

Urge for comfort and excitement have made gadgets indispensable part of our life. The technology-enabled gadgets not only facilitate and enrich our daily lives but also are interesting tools to challenge human imagination to design and implement new ubiquitous applications. Pervasive gaming, in which human interaction and game/scenario-dependent designs are often common practices, has proved to be one of the areas to successfully combine technology and the human fantasy. By moving away from games being played by humans and by focusing instead on games played by robots and giving humans the leading role of defining game strategies and players’ roles, this paper aims at bridging the two fields of robotics and wireless sensor/actuator networks and exploring their potentials in the field of pervasive gaming. A generic game development framework is introduced that accommodates different types of robots and various kinds of sensors and actuators. Being extensible and modular, the proposed framework can be used for a wide range of pervasive applications built upon sensors and actuators. To enable game development, a Wiimote-based robot identification and localization technique is presented. The proposed framework and robot identification, localization, control and communication mechanisms are evaluated by implementing a game example.

Computing and data intensive applications in physics, medicine, biology, graphics, and business intelligence require large and distributed infrastructures to address today’s and tomorrow’s challenges. For example, process mining applications are faced with terrabytes of event data and computationally expensive algorithms. Increasingly, computer grids are used to deal with such challenges. However, despite the availability of many software packages for grid applications, a good conceptual model of the grid is missing. Grid computing is often approached in an ad-hoc and engineering-like manner. This paper provides formal description of the grid in terms of a colored Petri net (CPN). The CPN can be seen as a reference model for grids and clarifies the basic concepts at a conceptual level. Moreover, the CPN allows for various kinds of analysis ranging from verification to performance analysis. In this paper, we show that our reference model allows for the analysis of various distribution strategies using simulation.

This paper presents the realisation, using a Service Oriented Architecture, of an approach for dynamic, flexible and extensible exception handling in workflows, based not on proprietary frameworks, but on accepted ideas of how people actually work. The resultant service implements a detailed taxonomy of workflow exception patterns to provide an extensible repertoire of self-contained exception-handling processes called exlets, which may be applied at the task, case or specification levels. When an exception occurs at runtime, an exlet is dynamically selected from the repertoire depending on the context of the exception and of the particular work instance. Both expected and unexpected exceptions are catered for in real time, so that 'manual handling' is avoided.

Organizations, to function effectively and expand their boundaries, require a deep insight into both process orchestration and choreography of cross-organization business processes. The set of requirements for service interactions is significant, and has not yet been sufficiently refined. Service Interaction Patterns studies by Barros et al. demonstrate this point. However, they overlook some important aspects of service interaction of bilateral and multilateral nature. Furthermore, the definition of these patterns are not precise due to the absence of a formal semantics. In this paper, we analyze and present a set of patterns formed around the subset of patterns documented by Barros et al. concerned with Request-Reply interactions, and extend these ideas to cover multiple parties and multiple messages. We concentrate on the interaction between multiple parties, and analyze issues of a non-guaranteed response and different aspects of message handling. We propose one configurable, formally defined, conceptual model to describe and analyze options and variants of request-reply patterns. Furthermore, we propose a graphical notation to depict every pattern variant, and formalize the semantics by means of Coloured Petri Nets. In addition, we apply this pattern family to evaluate WS-BPEL v2.0 and check how selected pattern variants can be operationalized in Oracle BPEL PM.

Inter-organizational business cooperations can be described from different viewpoints each fulfilling a specific purpose. Since all viewpoints describe the same system they must not contradict each other, thus, must be consistent. Consistency can be checked based on common semantic concepts of the different viewpoints. This is sufficient for equal concepts, while weakly related concepts, e.g. related to runtime behavior of viewpoints, have to be considered explicitly. In this paper we identify dynamic consistency issues correlated to the runtime behavior between value and coordination viewpoints on behalf of an example. In particular, an issue class on occurrence estimations of execution options and an issue class on granularity differences in modelling are identified and illustrated.

This paper presents WorkflowNet2BPEL4WS a tool to automatically map a graphical workflow model expressed in terms of Workflow Nets (WF-nets) onto BPEL. The Business Process Execution Language for Web Services (BPEL) has emerged as the de-facto standard for implementing processes and is supported by an increasing number of systems (cf. the IBM WebSphere Choreographer and the Oracle BPEL Process Manager). While being a powerful language, BPEL is difficult to use. Its XML representation is very verbose and only readable for the trained eye. It offers many constructs and typically things can be implemented in many ways, e.g., using links and the flow construct or using sequences and switches. As a result only experienced users are able to select the right construct. Some vendors offer a graphical interface that generates BPEL code. However, the graphical representations are a direct reflection of the BPEL code and not easy to use by end-users. Therefore, we provide a mapping from WF-nets to BPEL. This mapping builds on the rich theory of Petri nets and can also be used to map other languages (e.g., UML, EPC, BPMN, etc.) onto BPEL. To evaluate WorkflowNet2BPEL4WS we used more than 100 processes modeled using Protos (the most widely used business process modeling tool in the Netherlands), automatically converted these into CPN Tools, and applied our mapping. The results of these evaluation are very encouraging and show the applicability of our approach.

Web services are becoming more and more complex, involving numerous interacting business objects within complex distributed processes. In order to fully explore Web service business opportunities, while ensuring a correct and reliable execution, analyzing and tracking Web services interactions will enable them to be well understood and controlled. The work described in this paper is a contribution to these issues for Web services based process applications. This article describes a novel way of applying process mining techniques to Web services logs in order to enable "Web service intelligence". Our work attempts to apply Web service log-based analysis and process mining techniques in order to provide semantical knowledge about the context of and the reasons for discrepancies between process models and related instances. An erratum to this chapter can be found at http://dx.doi.org/10.1007/11914853_71.

In our current connected wireless world, mobile devices are enabled to use various networking facilities. Although this enables mobile users to communicate any time and any place, it may also be very intrusive. There is a high need to manage the information stream a user receives on his/her mobile device. Context-awareness seems to be a promising way to manage this information stream and to provide the means to communicate at the right time in the right way. Current context-aware applications benefit from the user context (e.g. location information), however, they do not consider the quality of service (QoS) offered by various networks (i.e. only best-effort QoS is considered). The research discussed in this paper focuses on a QoS- and context-aware service infrastructure supporting the development of mobile applications in a heterogeneous network environment. We argue that the use of context information helps to better capture the user’s required QoS and improves the delivered QoS.

The control of actions performed by parties involved in a decentralized cross-organizational workflow is done by several independent workflow engines. Due to the lack of a centralized coordination control, an auditing is required which supports a reliable and secure detection of malicious actions performed by these parties. In this paper we identify several issues which have to be resolved for such a secure logging system. Further, security requirements for a decentralized data store are investigated and evaluated with regard to decentralized data stores.

This paper presents an ontology-based framework for repurposing learning object components. Unlike the usual practice where learning object components are assembled manually, the proposed framework enables on-the-fly access and repurposing of learning object components. The framework supports two processes: the decomposition of learning objects into their components as well as the automatic assembly of these components in real-world applications. For now, the framework supports slide presentations. As an application, we will present in this paper the integration of this functionality in MS PowerPoint.

We report on an a set of experiments carried out in the context of the Flemish OntoBasis project. Our purpose is to extract semantic relations from text corpora in an unsupervised way and use the output as preprocessed material for the construction of ontologies from scratch. The experiments are evaluated in a quantitative and impressionistic manner. We have worked on two corpora: a 13M words corpus composed of Medline abstracts related to proteins (SwissProt), and a small legal corpus (EU VAT directive) consisting of 43K words. Using a shallow parser, we select functional relations from the syntactic structure subject-verb-direct-object. Those functional relations correspond to what is a called a lexon. The selection is done using prepositional structures and statistical measures in order to select the most relevant lexons. Therefore, the paper stresses the filtering carried out in order to discard automatically all irrelevant structures. Domain experts have evaluated the precision of the outcomes on the SwissProt corpus. The global precision has been rated 55%, with a precision of 42% for the functional relations or lexons, and a precision of 76% for the prepositional relations. For the VAT corpus, a knowledge engineer has judged that the outcomes are useful to support and can speed up his modelling task. In addition, a quantitative scoring method (coverage and accuracy measures resulting in a 52.38% and 47.12% score respectively) has been applied.

We present STYPES, a system that rewrites ontology-mediated queries with linear tuple-generating dependencies and conjunctive queries to equivalent nonrecursive datalog (NDL) queries. The main feature of STYPES is that it produces polynomial-size rewritings whenever the treewidth of the input conjunctive queries and the size of the chases for the ontology atoms as well as their arity are bounded; moreover, the rewritings can be constructed and executed in LOGCFL, indicating high parallelisability in theory. We show experimentally that Apache Flink on a cluster of machines with 20 virtual CPUs is indeed able to parallelise execution of a series of NDL-rewritings constructed by STYPES, with the time decreasing proportionally to the number of CPUs available.

Time modeling is a crucial feature in many application domains. However, temporal information often is not crisp, but is uncertain, subjective and vague. This is particularly true when representing historical information, as historical accounts are inherently imprecise. Similarly, we conjecture that in the Semantic Web representing uncertain temporal information will be a common requirement. Hence, existing approaches for temporal modeling based on crisp representation of time cannot be applied to these advanced modeling tasks. To overcome these difficulties, in this paper we present fuzzy interval-based temporal model capable of representing imprecise temporal knowledge. Our approach naturally subsumes existing crisp temporal models, i.e. crisp temporal relationships are intuitively represented in our system. Apart from presenting the fuzzy temporal model, we discuss how this model is integrated with the ontology model to allow annotating ontology definitions with time specifications. © Springer-Verlag Berlin Heidelberg 2003.

Process mining deals with the extraction of knowledge from event logs. One important task within this research field is denoted as conformance checking, which aims to diagnose deviations and discrepancies between modeled behavior and real-life, observed behavior. Conformance checking techniques still face some challenges, among which scalability, timeliness and traceability issues. In this paper, we propose a novel conformance analysis methodology to support the real-time monitoring of event-based data streams, which is shown to be more efficient than related approaches and able to localize deviations in a more fine-grained manner. Our developed approach can be directly applied in business process contexts where rapid reaction times are crucial; an exhaustive case example is provided to evidence the validity of the approach. ispartof: pages:345-363 ispartof: On the Move Federated Conferences & Workshops vol:8841 pages:345-363 ispartof: International Conference on Cooperative Information Systems (CoopIS 2014) location:Amantea, Calabria (Italy) date:27 Oct - 31 Oct 2014 status: published

In this work we deal with the issue of optimizing the global Quality of Service (QoS) of a Grid Federation by means of an aggregation model specifically designed for intelligent agents assisting Grid nodes. The proposed model relies on an algorithm, called FGF (Friendship and Group Formation), by which the nodes select their partners with the aim of maximizing the QoS they perceive when a computational task requires the collaboration of several Grid nodes. In the proposed solution, in order to assist the selection of the partners, a suitable trust model has been designed. Since jobs sent to Grid Federations hold complex requirements involving well defined resource sets, trust values are calculated for specific sets of resources. We also provide a theoretical foundation and some experiments to prove that, by means of the adoption of the FGF algorithm suitably supported by the proposed trust model, the Grid Capital (which respect the global QoS) of the Grid Federation is eventually improved.

Business process mining is a well-established field of research which focuses on the automatic retrieval and analysis of process flows, extracted from event logs which are the outcome of today's omnipresent information systems. The discovery and representation of these models is based on techniques that come in all shapes and forms. Most notably, procedurally-based algorithms such as Heuristics Miner have been used successfully for this purpose. Also, declarative process model miners have been proposed, which give other insights into the model by generating rules that apply on the activities. This paper proposes an integrated approach to combining these paradigms to discover process models that contain best of both worlds to enrich insights into the event logs under scrutiny. The findings have been implemented as a ProM plug-in that is based on Heuristics Miner and Declare miner. ispartof: FEB Research Report KBI_1413 nrpages: 13 status: published

Software-as-a-Service (SaaS) is a type of cloud computing in which a tenant rents access to a shared, typically web-based application hosted by a provider. Access control for SaaS should enable the tenant to control access to data that are located at the provider based on tenant-specific access control policies. To achieve this, state-of-practice SaaS applications provide application-specific access control configuration interfaces and as a result, the tenant policies are evaluated at the provider side. This approach does not support collaboration between provider-side and tenant-side access control infrastructures, thus scattering tenant access control management and forcing the tenant to disclose sensitive access control data. To address these issues, we describe the concept of federated authorization in which management and evaluation of the tenant policies is externalized from the SaaS application to the tenant. This centralizes tenant access control management and lowers the required trust in the provider. This paper presents a generic middleware architecture for federated authorization, describing required extensions to current policy languages and a distributed execution environment. Our evaluation explores the trade-off between performance and security and shows that federated authorization is a feasible and promising approach. ispartof: pages:342-359 ispartof: On the Move to Meaningful Internet Systems: OTM 2013 Conferences vol:8185 pages:342-359 ispartof: On the Move to Meaningful Internet Systems: OTM 2013 Conferences location:Austria date:9 Sep - 13 Sep 2013 status: published

AgreementMaker is one of the leading ontology matching systems, thanks to its combination of a flexible and extensible framework with a comprehensive user interface. In many domains, such as the biomedical, ontologies are becoming increasingly large thus presenting new challenges. We have developed a new core framework, AgreementMakerLight, focused on computational efficiency and designed to handle very large ontologies, while preserving most of the flexibility and extensibility of the original AgreementMaker framework. We evaluated the efficiency of AgreementMakerLight in two OAEI tracks: Anatomy and Large Biomedical Ontologies, obtaining excellent run time results. In addition, for the Anatomy track, AgreementMakerLight is now the best system as measured in terms of F-measure. Also in terms of F-measure, AgreementMakerLight is competitive with the best OAEI performers in two of the three tasks of the Large Biomedical Ontologies track that match whole ontologies.

UMR IATE : Axe 5 Application intégrée de la connaissance, de l’information et des technologies permettant d’accroître la qualité et la sécurité des aliments. Contact: Fatiha.Sais@lri.fr, rallou@supagro.inra.fr, sebastien.destercke@supagro.inra.fr UMR IATE : Axe 5 Application intégrée de la connaissance, de l’information et des technologies permettant d’accroître la qualité et la sécurité des aliments. Contact: Fatiha.Sais@lri.fr, rallou@supagro.inra.fr, sebastien.destercke@supagro.inra.fr; International audience; It often happens that different references (i.e. data descriptions), possibly coming from different heterogeneous data sources, concern the same real world entity. In such cases, it is necessary: (i) to detect, through reconciliation methods, whether different data descriptions refer to the same real world entity and (ii) to fuse them into a unique representation. Here we assume the reference reconciliation is solved, and we propose a fusion method based on possibility theory, able to cope with uncertainty and with ontological knowledge. An imple- mentation using W3C standards is provided. Rising from the fusion process, an ontology enrichment procedure is proposed to complete the global ontology.

Decision making is tightly related to the understanding of the design and manufacturing practices. In our previous work, we proposed an intuitive approach for geometric modeling in CAD, based on the integration of the user’s knowledge with virtual design tools. This approach facilitates the design of the CAD models using deformations. Deformations are done by the bias of a layered architecture which captures and represents the user’s knowledge at five semantic levels. The idea of using semantics was to provide high level modeling primitives for the data model in order to facilitate the design for a non-expert user. This paper discusses the natural language representation of the user-specific knowledge by means of ontologies and its major contribution to the computer-human interaction. The approach is demonstrated on an industrial example of surface deformation for the design of a car parcel shelf.

Today's industries require ontology engineering to be more community vision driven and ontological resources have more dimensions. This paper shows our achieved goals in the EU Prolix pro ject. Firstly, we analyze the user requirements, including tuning Business Process Modelling e_orts into ontology engineering tasks. Secondly, we design a scalable and community driven architecture for ontology development. Then, feasible ontology models are created. The task of creating ontol- ogy models depends heavily on conceptual architecture of ontology based competence analysis. We illustrate with the requirement analysis from BT (British Telecom).

Evaluation of ontologies is increasingly becoming important as the number of available ontologies is steadily growing. Ontology evaluation is a labour intensive and laborious job. Hence, the importance to come up with automated methods. Before automated methods achieve reliability and widespread adoption, these methods themselves have to be assessed first by human experts. We summarise experiences acquired when trying to assess an automated ontology evaluation method. Previously we have implemented and evaluated a light-weight automatic ontology evaluation method that can be easily applied by knowledge engineers to rapidly determine whether or not the most important notions and relationships are represented in a set of ontology triplets. Domain experts have contributed to the assessment effort. Various assessment experiments have been carried out. In this paper, we focus particularly on the practical lessons learnt, in particular the limitations that result from real life constraints, rather than onthe precise method to automatically evaluate results of an ontology miner. A typology of potential evaluation biases is applied to demonstrate the substantial impact conditions in which an evaluation happens can have on the reliability of the outcomes of an evaluation exercise. As a result, the notion of ``meta-evaluation of ontologies'' is introduced and its importance illustrated. The main conclusion is that still more domain experts have to be involved, which is exactly what we try to avoid by applying an automated evaluation procedure. A catch-22 situation ?

We present work in progress on automated and ontology-guided discovery, extraction and mapping of information sources on the Semantic Web. It concerns an \emph{ontology-guided focused crawler} to discover and match different data sources. We have developed an automated ontology-matcher embedded in the crawler that relates semantic web documents found during the crawl to an initial topic ontology that describes the domain of interest of the crawl. Similarity coefficients resulting from the matching process are used to guide the crawler to the information sources relevant to the modelled domain of interest. In addition, the matching process also provides links between the different data sources, which helps in the integration of this data at a later stage. In this paper, the overall architecture, the various modules and methods actually implemented are presented.