Personal BPM - Bringing the power of Business Process Management to the user

External and internal factors force companies to be flexible in their business processes. However, the information systems used in the companies are often too complex and the implemented process models are too rigid to quickly adopt changing determining conditions. This leads to a loss of efficiency since various tasks that would be suitable for the execution by workflow management systems must be performed manually. The presented approach for a solution solves this problem by offering a method to exploit the automation potential by using suitable flexible tools and a target-group oriented procedure model. Compared to existing approaches this method does not try to solve the problem on a company level. Instead the focus is on the individual employee who will be enabled to improve his personal workflows

Efficient Attribute Based Access Control for RESTful Services

Abstract. The popularity of REST grows more and more and so does the need for fine-grained access control for RESTful services. Attribute Based Access Control (ABAC) is a very generic concept that covers multiple different access control mechanism. XACML is an implementation of ABAC based on XML and is established as a standard mechanism. Its flexibility opens the opportunity to specify detailed security policies. But on the other hand it has some drawbacks regarding maintenance and performance when the complexity of security policies grows. Long processing times for authorization requests are the consequence in environments that require fine-grained access control. We describe how to design a security policy in a resource oriented environment so that its drawbacks are minimized. The results are faster processing times for access requests and an easy to manage concept for security policies for RESTful services

Ontologies for the interoperability of multiagent electricity markets simulation platforms

Electricity markets worldwide are complex and dynamic environments with very particular characteristics. These are the result of electricity markets’ restructuring and evolution into regional and continental scales, along with the constant changes brought by the increasing necessity for an adequate integration of renewable energy sources. The rising complexity and unpredictability in electricity markets has increased the need for the intervenient entities in foreseeing market behaviour. Market players and regulators are very interested in predicting the market’s behaviour. Market players need to understand the market behaviour and operation in order to maximize their profits, while market regulators need to test new rules and detect market inefficiencies before they are implemented. The growth of usage of simulation tools was driven by the need for understanding those mechanisms and how the involved players' interactions affect the markets' outcomes. Multi-agent based software is particularly well fitted to analyse dynamic and adaptive systems with complex interactions among its constituents, such as electricity markets. Several modelling tools directed to the study of restructured wholesale electricity markets have emerged. Still, they have a common limitation: the lack of interoperability between the various systems to allow the exchange of information and knowledge, to test different market models and to allow market players from different systems to interact in common market environments. This dissertation proposes the development and implementation of ontologies for semantic interoperability between multi-agent simulation platforms in the scope of electricity markets. The added value provided to these platforms is given by enabling them sharing their knowledge and market models with other agent societies, which provides the means for an actual improvement in current electricity markets studies and development. The proposed ontologies are implemented in MASCEM (Multi-Agent Simulator of Competitive Electricity Markets) and tested through the interaction between MASCEM agents and agents from other multi-agent based simulators. The implementation of the proposed ontologies has also required a complete restructuring of MASCEM’s architecture and multi-agent model, which is also presented in this dissertation. The results achieved in the case studies allow identifying the advantages of the novel architecture of MASCEM, and most importantly, the added value of using the proposed ontologies. They facilitate the integration of independent multi-agent simulators, by providing a way for communications to be understood by heterogeneous agents from the various systems.Os mercados de energia elétrica são ambientes complexos e dinâmicos que possuem características particulares. Tais características são resultado da sua reestruturação e evolução a escalas regionais e, por vezes, até continentais. A crescente necessidade de adaptação dos mecanismos existentes para que possam fazer face à integração adequada de fontes de energia renováveis também contribui para a peculiaridade destes mercados. A constante complexidade e imprevisibilidade nos mercados de eletricidade aumentou a necessidade das entidades neles intervenientes preverem o seu comportamento. Os reguladores precisam testar e detetar ineficiências nos algoritmos do mercado antes de serem implementados. Por outro lado, os agentes compradores e vendedores têm a necessidade de compreender o comportamento do mercado e o seu modo de operação, de modo a maximizarem os seus lucros ou minimizarem os seus custos. O crescimento do uso de ferramentas de simulação foi motivado pela necessidade de compreensão destes mecanismos e de como as interações entre as entidades intervenientes afetam os resultados dos mercados. Software baseado em tecnologia multiagente é particularmente adequado para estudar e analisar sistemas dinâmicos e adaptativos com interações complexas entre os seus constituintes, tais como os mercados de energia elétrica. Diversas ferramentas de modelação direcionadas ao estudo dos mercados reestruturados da eletricidade foram surgindo, como por exemplo o MASCEM (Multi-Agent Simulator of Competitive Electricity Markets). No entanto, estas ferramentas de simulação partilham uma limitação comum: a falta de interoperabilidade entre os vários sistemas, que permita o intercâmbio de modelos e conhecimento, e ainda o teste e estudo de diferentes modelos de mercado. O MASCEM é um simulador multiagente de mercados competitivos de energia elétrica, que tem vindo a ser desenvolvido desde 2003. Inclui os principais modelos de mercado e as principais entidades que nele participam, permitindo o estudo dos modelos e comportamento do mercado e de cada um dos respetivos participantes. No entanto, com as constantes atualizações que o MASCEM tem acomodado, o seu ambiente tornou-se excessivamente complexo, revelando a fragilidade da sua arquitetura e da plataforma de comunicação dos agentes. Deste modo, tornou-se essencial reestruturar o sistema por completo, definindo uma nova arquitetura, um novo modelo multiagente, o uso de mecanismos adequados para lidar com os requisitos de tempos de execução, e, para facilitar a interoperabilidade com sistemas externos, o uso de semântica nas mensagens trocadas entre os principais intervenientes do mercado. Esta dissertação propõe, além da reestruturação completa da arquitetura e modelo multiagente do simulador MASCEM, o desenvolvimento e implementação de ontologias para a interoperabilidade semântica entre plataformas multiagente no âmbito dos mercados de energia elétrica. O valor acrescentado a estas ferramentas é dado através da partilha do seu conhecimento e modelos de mercado com outras sociedades de agentes, dispondo assim dos meios para uma efetiva melhoria nos estudos e desenvolvimento dos atuais mercados de eletricidade. Os resultados obtidos nos casos de estudo permitem identificar a adequação da nova arquitetura do simulador MASCEM, bem como as vantagens do uso das ontologias propostas. O uso destas ontologias facilita a integração de simuladores multiagente independentes, disponibilizando um modo para a compreensão das mensagens trocadas entre os agentes de sistemas heterogéneos

Forschungsbericht Universität Mannheim 2008 / 2009

Die Universität Mannheim hat seit ihrer Entstehung ein spezifisches Forschungsprofil, welches sich in ihrer Entwicklung und derz eitigen Struktur deutlich widerspiegelt. Es ist geprägt von national und international sehr anerkannten Wirtschafts- und Sozialwissenschaften und deren Vernetzung mit leistungsstarken Geisteswissenschaften, Rechtswissenschaft sowie Mathematik und Informatik. Die Universität Mannheim wird auch in Zukunft einerseits die Forschungsschwerpunkte in den Wirtschafts- und Sozialwissenschaften fördern und andererseits eine interdisziplinäre Kultur im Zusammenspiel aller Fächer der Universität anstreben

Multimetal smithing : An urban craft in rural settings?

Multimetal smithing should be defined as the use of more than one metal and/or different metalworking techniques within thesame crafts-milieu. This complex metalworking has long been linked to centrality, central places and urbanity in Scandinavia.It has been extensively argued that fine casting and smithing, as well as manufacture utilizing precious metals was exclusivelyundertaken within early urban settings or the “central places” pre-dating these. Furthermore, the presence of complex metalcraftsmanship has been used as a driving indicator of the political, social and economic superiority of certain sites, therebyenhancing their identity as “centralities”.Recent research has come to challenge the universality of this link between urbanity, centrality and complex metalworkingas sites in rural settings with evidence of multimetal smithing are being identified. This shows that the relationship between thecraft and centrality (urbanity) must be nuanced and that perhaps multimetal craftsmanship should be reconsidered as an urbanindicator.The thesis project “From Crucible and onto Anvil” started in 2015 and focuses on sites housing remains of multimetalcraftsmanship dating primarily from 500-1000 AD. Within the project a comprehensive survey of sites will be used to evaluate thepresence of multimetal craftsmanship in the landscape. Sites in selected target areas will also be subject to intra-site analysisfocusing on workshop organisation, production output, metalworking techniques and chronological variances.A key aim in the project is to elucidate the conceptual aspects of complex metalworking. The term multimetality is used toanalytically frame all the societal and economic aspects of multimetal craftsmanship. Through this inclusive perspective both thecraftsmanship and the metalworkers behind it are positioned within the overall socioeconomic framework. The metalworkers,their skills and competences as well as the products of their labour are viewed as dynamic actors in the landscape and on thearenas of political economy of the Late Iron Age.The survey has already revealed interesting aspects concerning multimetal smithing and urbanity. Although the multimetalsites do cluster against areas of early urban development there are also other patterns emerging. Multimetal craftsmanship – both as practice and concept – was well represented in both rural peripheral settings and urban crafts-milieus. This means that therole of multimetality as part of an “urban conceptual package” is crucial to investigate. Such an approach will have the dual endsof properly understanding the craft and its societal implications, but also further the knowledge of the phenomenon of urbanityas a whole. Was multimetal smithing part of an “urban package” that spread into the rural landscape? Did the multimetality differbetween urban and rural crafts-milieus? How does early urbanity relate to the chronology of multimetal craftsmanship?This paper aims to counter these questions using examples from the survey of multimetal sites conducted within the thesisproject. A comparison between selected sites will be presented. The purpose of this is to evaluate the role of multimetality withinthe “urban package” and discuss the role of complex metalworking in the establishment of urban arenas of interaction in LateIron Age Scandinavia

Forschungsbericht Universität Mannheim 2006 / 2007

Sie erhalten darin zum einen zusammenfassende Darstellungen zu den Forschungsschwerpunkten und Forschungsprofilen der Universität und deren Entwicklung in der Forschung. Zum anderen gibt der Forschungsbericht einen Überblick über die Publikationen und Forschungsprojekte der Lehrstühle, Professuren und zentralen Forschungseinrichtungen. Diese werden ergänzt um Angaben zur Organisation von Forschungsveranstaltungen, der Mitwirkung in Forschungsausschüssen, einer Übersicht zu den für Forschungszwecke eingeworbenen Drittmitteln, zu den Promotionen und Habilitationen, zu Preisen und Ehrungen und zu Förderern der Universität Mannheim. Darin zeigt sich die Bandbreite und Vielseitigkeit der Forschungsaktivitäten und deren Erfolg auf nationaler und internationaler Ebene

Portability of Process-Aware and Service-Oriented Software: Evidence and Metrics

Modern software systems are becoming increasingly integrated and are required to operate over organizational boundaries through networks. The development of such distributed software systems has been shaped by the orthogonal trends of service-orientation and process-awareness. These trends put an emphasis on technological neutrality, loose coupling, independence from the execution platform, and location transparency. Execution platforms supporting these trends provide context and cross-cutting functionality to applications and are referred to as engines. Applications and engines interface via language standards. The engine implements a standard. If an application is implemented in conformance to this standard, it can be executed on the engine. A primary motivation for the usage of standards is the portability of applications. Portability, the ability to move software among different execution platforms without the necessity for full or partial reengineering, protects from vendor lock-in and enables application migration to newer engines. The arrival of cloud computing has made it easy to provision new and scalable execution platforms. To enable easy platform changes, existing international standards for implementing service-oriented and process-aware software name the portability of standardized artifacts as an important goal. Moreover, they provide platform-independent serialization formats that enable the portable implementation of applications. Nevertheless, practice shows that service-oriented and process-aware applications today are limited with respect to their portability. The reason for this is that engines rarely implement a complete standard, but leave out parts or differ in the interpretation of the standard. As a consequence, even applications that claim to be portable by conforming to a standard might not be so. This thesis contributes to the development of portable service-oriented and process-aware software in two ways: Firstly, it provides evidence for the existence of portability issues and the insufficiency of standards for guaranteeing software portability. Secondly, it derives and validates a novel measurement framework for quantifying portability. We present a methodology for benchmarking the conformance of engines to a language standard and implement it in a fully automated benchmarking tool. Several test suites of conformance tests for two different languages, the Web Services Business Process Execution Language 2.0 and the Business Process Model and Notation 2.0, allow to uncover a variety of standard conformance issues in existing engines. This provides evidence that the standard-based portability of applications is a real issue. Based on these results, this thesis derives a measurement framework for portability. The framework is aligned to the ISO/IEC Systems and software Quality Requirements and Evaluation method, the recent revision of the renowned ISO/IEC software quality model and measurement methodology. This quality model separates the software quality characteristic of portability into the subcharacteristics of installability, adaptability, and replaceability. Each of these characteristics forms one part of the measurement framework. This thesis targets each characteristic with a separate analysis, metrics derivation, evaluation, and validation. We discuss existing metrics from the body of literature and derive new extensions speciffically tailored to the evaluation of service-oriented and process-aware software. Proposed metrics are defined formally and validated theoretically using an informal and a formal validation framework. Furthermore, the computation of the metrics has been prototypically implemented. This implementation is used to evaluate metrics performance in experiments based on large scale software libraries obtained from public open source software repositories. In summary, this thesis provides evidence that contemporary standards and their implementations are not sufficient for enabling the portability of process-aware and service-oriented applications. Furthermore, it proposes, validates, and practically evaluates a framework for measuring portability

Clinical Studies, Big Data, and Artificial Intelligence in Nephrology and Transplantation

In recent years, artificial intelligence has increasingly been playing an essential role in diverse areas in medicine, assisting clinicians in patient management. In nephrology and transplantation, artificial intelligence can be utilized to enhance clinical care, such as through hemodialysis prescriptions and the follow-up of kidney transplant patients. Furthermore, there are rapidly expanding applications and validations of comprehensive, computerized medical records and related databases, including national registries, health insurance, and drug prescriptions. For this Special Issue, we made a call to action to stimulate researchers and clinicians to submit their invaluable works and present, here, a collection of articles covering original clinical research (single- or multi-center), database studies from registries, meta-analyses, and artificial intelligence research in nephrology including acute kidney injury, electrolytes and acid–base, chronic kidney disease, glomerular disease, dialysis, and transplantation that will provide additional knowledge and skills in the field of nephrology and transplantation toward improving patient outcomes