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Hyperledger Fabric is a very large project under the umbrella of the Linux Foundation, with hundreds of developers involved. In this paper we will illustrate how the application of fact-based modeling will help us in understanding some basic features of the blockchain concept as is used in Hyperledger Fabric (HLF) and that it can serve as a conceptual blueprint of HLF for all involved to use.

Business Process Management is a powerful approach forthe automation of collaborative business processes. Recently conceptshave been introduced to allow batch processing in business processesaddressing the needs of different industries. The existing batch activityconcepts are limited in their flexibility. In this paper we contribute differentstrategies for modeling and executing processes including batch workto improve the flexibility 1) of business processes in general and 2) of thebatch activity concept. The strategies support different flexibility aspects(i.e., variability, looseness, adaptation, and evolution) of batch activities.The strategies provide a systematic approach to categorize existing andfuture batch-enabled BPM systems. Furthermore, the paper provides asystem architecture independent from existing BPM systems, which allowsfor the support of all the strategies. The architecture can be usedwith different process languages and existing execution environments ina non-intrusive manner.

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.

Distributing software processes by software producing organizations (SPOs) is emerging increasingly due to benefits that global software engineering (GSE) brings in terms of cost reduction, leveraging competencies, and market expansion. However, these organizations are facing communication and project control issues that can slow down the overall organization performance. Therefore, SPOs should be able to manage inter-dependencies among the tasks distributed to the globally dispersed teams. We analyze existing works and product software companies’ best practices in coordinating tasks in GSE. This paper specifically focuses on constructing methodological support for task coordination that can be influenced by the situational factors at the companies. The support comprises a framework and a method developed by using a method engineering approach. We introduce the framework that depicts the aspects that should be examined by companies and the method that elaborates the practices to guide companies to coordinate tasks in GSE projects. The validation results show that the framework and the method are accepted by experts regarding completeness and applicability to help SPOs in managing coordination among globally distributed teams.

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.

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.

The last years have seen the definition of many languages, models and standards tailored to specify and enforce access control policies, but such frameworks do not provide methodological support during the policy specification process. In particular, they do not provide facilities for the analysis of the social context where the system operates. In this paper we propose a model-driven approach for the specification and analysis of access control policies. We build this framework on top of SI*, a modeling language tailored to capture and analyze functional and security requirements of socio-technical systems. The framework also provides formal mechanisms to assist policy writers and system administrators in the verification of access control policies and of the actual user-permission assignment.

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.

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.

The literature on continuous monitoring of cross-organizational processes, executed within virtual enterprises or business networks, considers monitoring as an issue regarding the network formation, since what can be monitored during process execution is fixed when the network is established. In particular, the impact of evolving agreements in such networks on continuous monitoring is not considered. Also, monitoring is limited to process execution progress and simple process data. In this paper, we extend the possible monitoring options by linking monitoring requirements to generic clauses in agreements established across a network and focus on the problem of preserving the continuous monitorability of these clauses when the agreements evolve, i.e. they are introduced, dropped, or updated. We discuss mechanisms to preserve continuous monitorability in a business network for different types of agreement evolution and we design a conceptual and technical architecture for a continuous monitoring IT infrastructure that implements the requirements derived from such mechanisms.

The competition in globalized markets forces organizations to provide mass-customized integrated solutions for customers. Mass-customization of integrated solutions by business network requires adaptive interactions between parties to address emerging requirements of customers. These adaptive interactions need to be enabled by dynamic networked business processes (DNBP) that are supported by high quality information. However, the dynamic collaboration between parties can result in information quality (IQ) issues such as information syntactic and semantic misalignment, information leakage, and unclear information ownership. To counter negative consequences of poor IQ on the performance, the orchestrator of business network needs to clearly recognize these IQ issues. In this paper, we develop and evaluate a framework to address potential IQ issues related to DNBP. The development of the framework is based on a three step methodology that includes the characterization of dynamism of networked business processes, the characterization of IQ dimensions, and the exploration of IQ issues. To evaluate the practical significance of the explored IQ issues, we conduct a case study in a service ecosystem that is shaped by a car leasing organization to provide integrated mobility solutions for customers.

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.

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.

To enable effective interorganisational collaborations, process providers have to disclose relevant parts of their local business processes in public process views. A public process view has to be consistent with the underlying private process. Local business processes are typically supported by transactions, which ensure a robust and reliable execution. Process views currently do not support the specification of transactional properties. This paper introduces transactional process views and studies how they can be constructed from an internal business process that is annotated with a transactional specification. This way, we provide a well-structured approach to obtain robust and reliable process behaviour at the public external level, thus facilitating trustworthy, fine-grained collaboration between organisations. We consider various transactional models. The feasibility of the approach is shown by means of a case study.

Resources tend to follow certain availability patterns, due to the maintenance cycles, work shifts, etc. Such availability patterns heavily influence the efficiency and effectiveness of enterprise process scheduling. Most existing process scheduling and resource management approaches focus on process structure and resource utilisation, yet neglect the resource availability constraints. In this paper, we investigate how to plan the business process instances scheduling in accordance with resource availability patterns, so that enterprise resources can be rationally and sufficiently used. Three planning strategies are proposed to maximise the process instance throughput using different criteria.

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.

Being able to determine the degree of similarity between process models is important for management, reuse, and analysis of business process models. In this paper we propose a novel method to determine the degree of similarity between process models, which exploits their semantics. Our approach is designed for labeled Petri nets as these can be seen as a foundational theory for process modeling. As the set of traces of a labeled Petri net may be infinite, the challenge is to find a way to represent behavioral characteristics of a net in a finite manner. Therefore, the proposed similarity measure is based on the notion of so-called "principal transition sequences", which aim to provide an approximation of the essence of a process model. This paper defines a novel similarity measure, proposes a method to compute it, and demonstrates that it offers certain benefits with respect to the state-of-the-art in this field.

Nowadays, organizations collaborate in business chains using dynamic service outsourcing to deliver complex products and services. To enable the flexible formation of business chains, organizations need to ensure that their business protocols are compatible. If the business protocols are incompatible, then the organizations cannot form a business chain. Protocol adaptors can resolve incompatibilities between business protocols during chain formation. By using the customer order decoupling point, we identify three different business chain structures. For each chain structure, we identify how adaptation can be used to support flexible chain formation.

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.

This paper addresses the following problem: given two or more business process models, create a process model that is the union of the process models given as input. In other words, the behavior of the produced process model should encompass that of the input models. The paper describes an algorithm that produces a single configurable process model from an arbitrary collection of process models. The algorithm works by extracting the common parts of the input process models, creating a single copy of them, and appending the differences as branches of configurable connectors. This way, the merged process model is kept as small as possible, while still capturing all the behavior of the input models. Moreover, analysts are able to trace back from which original model(s) does a given element in the merged model come from. The algorithm has been prototyped and tested against process models taken from several application domains.

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.

A typical question for people dealing with administrative processes is: "When will my case be finished?". In this paper, we show how this question can be answered, using historic information in the form of event logs of the systems supporting these administrative processes. Many information systems record information about activities performed for past cases in logs. Hence, to provide insights into the remaining cycle time of a case, the current case can be compared to all past ones. The most trivial way of estimating the remaining cycle time of a case is by looking at the average cycle time and deducting the already past time of the case under consideration. However, in this paper we show how to compute the remaining cycle time using non-parametric regression on the data recorded in event logs. An experiment is presented that demonstrates that our techniques perform well on logs taken from practice.

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.

While business processes are typically handled differently among companies, many of them are variations of a common process like procurement or invoicing. To gain synergy effects from corporate mergers, process analysts align such processes by identifying and seamlessly integrating overlapping process parts. To support this, we present in this paper an approach that merges two business process models which are depicted as Event-driven Process Chains into a single process model which can serve as a starting point for further process optimization. The approach has been implemented in the ProM process mining framework and can thus be used together with a wide range of other process mining and analysis techniques.

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.

The degree of flexibility of workflow management systems heavily influences the way business processes are executed. Constraint-based models are considered to be more flexible than traditional models because of their semantics: everything that does not violate constraints is allowed. Although constraint-based models are flexible, changes to process definitions might be needed to comply with evolving business domains and exceptional situations. Flexibility can be increased by run-time support for dynamic changes – transferring instances to a new model – and ad-hoc changes – changing the process definition for one instance. In this paper we propose a general framework for a constraint-based process modeling language and its implementation. Our approach supports both ad-hoc and dynamic change, and the transfer of instances can be done easier than in traditional approaches.

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.

Often research on online communities could be compared to archaeology [16] : researchers look at patterns in digital traces that members leave to characterise the community they belong to. Relatively easy access to these traces and a growing number of methods and tools to collect and analyse them make such analysis increasingly attractive. However, a researcher is faced with the difficult task of choosing which digital artefacts and which relations between them should be taken into account, and how the findings should be interpreted to say something meaningful about the community based on the traces of its members.In this paper we present a framework that allows categorising digital traces of an online community along five dimensions (people, documents, terms, links and time) and then describe a tool that supports the analysis of community traces by combining several of them, illustrating the types of analysis possible using a dataset from a weblog community.

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 the domain of business-to-business (B2B) collaboration, companies are pursuing the objective of electronically linking their business processes for improving their supply chains. For creating such inter-organizational collaboration, intra- and inter-organizational knowledge workers (IKWs) function as assisting experts. However, IKWs must not constantly "reinvent the wheel" but should instead be supported by a repository that contains knowledge about how to design business processes. Thus, this paper proposes the support of IKWs by a pattern repository for the effective and efficient design of inter-organizational business processes. A pattern is conceptually formulated knowledge that is technology independent. By storing patterns in a uniform specification template of a meta model, it is possible to perform systematic reasoning. Having information readily available about the technology support of individual patterns, IKWs can quickly analyse with which intersection of pattern sets it is possible to link intra-organizational business processes.

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.

This paper investigates basic research issues that need to be addressed in order to reuse learning objects in a flexible way. We propose an ontology based approach. Our ontology for learning objects defines content structures and relationships between their components. A conceptual framework for structuring learning objects and their components is introduced. Architectures like Horn's Information Blocks and the Darwin Information Typing Architecture are investigated as an approach to define learning object component types.

Increasing demands for interconnectivity, adaptivity and flexibility are leading to distributed component-based systems (DCBS) where components may dynamically join and leave a system at run-time. Our research is aimed at the development of an architecture for middleware for DCBS such that the extra-functional properties of resulting systems can be easily tailored to different requirements. To this end, we proposed an architecture based on the shared data space paradigm. This architecture provides a suite of distribution strategies [16] supporting different application usage patterns. We showed that using different distribution strategies for different usage patterns improved overall performance [17]. As is the case with other middleware for DCBS, the configuration of the selected distribution policies was fixed before run-time. Consequently, these systems cannot adapt to changes in usage patterns that may be due to the joining of leaving of the components in the system. In this paper, we propose a mechanism for the dynamic adaptation of distribution policies to the evolving behaviour of applications. This architecture improves over existing architectures for distributed shared data spaces by providing a mechanism for self-management. We experimentally demonstrate the benefits that may be gained by dynamic adaptation of distribution policies.

We would like to welcome you to the Proceedings of the Twelfth International Conference on Cooperative Information Systems (CoopIS 04). As in previous years, CoopIS is part of the federated conference On the Move (OTM) to Meaningful Internet Systems and Ubiquitous Computing, this year taking place in Agia Napa, Cyprus, together with the International Symposium on Distributed Objects and Applications (DOA) and the International Conference on Ontologies, Databases and Applications of Semantics for large-scale Information Systems (ODBASE).

Current workflow management systems require the explicit design of the workflows that express the business process of an organization. This process design is very time consuming and error prone. Considerable work has been done to develop heuristics to mine event-data logs to produce a process model that can support the workflow design process. However, all the existing heuristic-based mining algorithms have their limitations. To achieve more insight into these limitations the starting point in this paper is the α-algorithm [3] for which it is proved under which conditions and process constructs the algorithm works. After presentation of the α-algorithm, a classification is given of the process constructs that are difficult to handle for this type of algorithms. Then, for some constructs (i.e. short loops) it is illustrated in which way the α-algorithm can be extended so that it can correctly discover these constructs.

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.

Social Sciences identify similarity and mutual trust as main criteria to consider in group formation processes. On this basis, we present a group formation technique which exploits measures of both similarity and trust, in order to improve the compactness of groups in Online Social Networks. Similarity and trust have been jointly exploited to design two algorithms designed to match groups and users, in order to capture the gain of a user who desires to join with a group and the benefit of the group itself. Experimental results show that trust is more valuable than similarity in forming groups and that the two proposed algorithms are capable to deal with large networks.

International audience; Personalization is the new magic buzzword of application development. To make the complexity of today's application functionalities and information spaces "digestible", customization has become the new go-to technique. But while those technologies aim to ease the consumption of media for their users, they suffer from the same problematic: in the age of Big Data, applications have to cope with a conundrum of heterogeneous information sources that have to be perceived, processed and interpreted. Researchers tend to aim for a maximum degree of integration to create the perfect, all-embracing personalization. The results are wide-range, but overly complex systems that suffer from issues in performance and scalability. Starting from our own, similar experience, we argue for a personalization of personalization - a clear-cut customization of profiling by limiting the information maintained in the system to those elements that are crucially relevant for the target task. We demonstrate the concern based on an application developed in our laboratory: a system that profiles web users based on their browsing history, with the goal of personalizing digital advertisements.

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

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.

The knowledge economy is one of the cornerstones of our society. Our economic prosperity and development is derived for a large part from technical knowledge. Knowledge unlocks innovation, which in turns spawns new products or services, thereby enabling further economic growth. Hence, an information system unlocking scientific technical knowledge is an important asset for government policy and strategic decisions by industry. In this paper it is explained how business semantics management and related tools are applied to realise the above mentioned endeavour.