Bio-inspired anatomy for autonomous DPWS-compliant automation components

Dissertação apresentada na Faculdade de Ciências e Engenharia da Universidade Nova de Lisboa para obtenção do grau de Mestre em Engenharia Electrotécnica e de ComputadoresThis thesis approaches the use of the DPWS technology to implement web-services on small devices, addresses its limitations, and explains an architecture to solve it. An approach to an autonomous device’s simple architecture was realized, using DPWS, and was called Simple DPWS. The objective was to implement/simplify some features in a device in a way that the device can work on its own. The designed architecture is based on that each component has its framework of modules, having always at least the skeleton modules communication and Event Router-Scheduler. The communication module controls all the communication between the devices and the ERS is the responsible for the other modules’ real-time communication. The DPWS toolkit offers no capability of interacting with run-time-appearing services. Thus there was a necessity to do enhancements over the DPWS toolkit to have a dynamic stub and skeleton. This service was called the dynamic service. An experience was done connecting a DPWS toolkit sample service with the corresponding hand-created dynamic service. It was used the lighting service that consists on turning a lamp ON or OFF and getting its status. A GUI was done for the application to be more user-friendly. The results were satisfactory, as the connection worked

Proceedings of VikingPLoP 2013 Conference

This is the proceedings of VikingPLoP 2013 – a record of all papers workshopped during the conference. VikingPLoP is a Nordic conference of pattern languages of programs which took place this year in Horse Inn of Luomajärvi, Ikaalinen, Finland in March 2013. VikingPLoP was organized jointly by Tampere University of Technology and Hillside Europe. VikingPLoP 2013 was also sponsored by Wiley which provided books for the focus group reading session. The conference was organized in Finland for the second time in a row. Previous location in 2012 was in Saariselkä Lapland. In 2013 vikings were moving towards south and chose the Horse Inn in Ikaalinen as the venue as it offered a luxurious opportunity for participants to experience rustic romance, good food, horseback riding, traditional Finnish sauna, the nature, and wilderness tracks. In March the landscape was still covered in snow making the landscape ruggedly beautiful.The papers in this proceedings book are updated versions of the papers workshopped in the conference. In the beginning, participants submitted their papers for shepherding process. In the shepherding process, the shepherd, an experienced pattern writer, gave ideas and feedback for the author, colloquially known as a sheep. The sheep incorporated this feedback in to her paper. After three iterations of shepherding the paper was discussed at the conference in a writer's workshop. The workshop group gave comments, criticism and praise. After the conference the authors updated their papers according to the workshop feedback.This process of giving feedback was made possible by having a community of trust. Mutual trust was built by playing non-competitive games and by having social activities. VikingPLoP 2013 focused on patterns and their usage in various fields of expertise. These fields included a wide range of topics from educational patterns to safety patterns and embedded system's software architecture patterns. Bringing people together from various fields of expertise stimulates creativity and new ideas might emerge. These innovations are reflected in the papers in these proceedings. VikingPLoP 2013 was especially a conference for newcomers and over half of the participants were first time PLoP participants.These proceedings contain 9 papers. In addition, a book reading workshop was arranged with Bob Hanmer who presented his new title Pattern-Oriented Software Architecture for Dummies and discussed it with the participants using video conferencing tools

Élaboration d'un intergiciel pour relier les instruments aux grids

Les logiciels Grid sont en train de devenir une partie intégrale de la science électronique puisque la science moderne a besoin d'une grande capacité de calcul et une grande base de données d'information. Afin d'avoir des logiciels Grid capables de s'intégrer avec la science d'aujourd'hui, il faut que les instruments de mesure soient accessibles et représentés grâce à des intergiciels Grid de façon à ce qu'ils fassent partie de la Grid. Ce mémoire présente un résumé de la technologie des Grids, la conception du modèle et l'implémentation initiale de l'intergiciel appelé Grid Resource Instrument Model (GRIM) bâti à l'aide du WSRF pour les instruments et capteurs et inspiré par les standards IEEE1451, SensorML et TML. Le résultat de cette recherche est un intergiciel qui peut être utilisé par des applications Grid à des fins telles la planification et partage de laboratoires, le contrôle à distance d'instruments et la surveillance de capteurs

Service-based Fault Tolerance for Cyber-Physical Systems: A Systems Engineering Approach

Cyber-physical systems (CPSs) comprise networked computing units that monitor and control physical processes in feedback loops. CPSs have potential to change the ways people and computers interact with the physical world by enabling new ways to control and optimize systems through improved connectivity and computing capabilities. Compared to classical control theory, these systems involve greater unpredictability which may affect the stability and dynamics of the physical subsystems. Further uncertainty is introduced by the dynamic and open computing environments with rapidly changing connections and system configurations. However, due to interactions with the physical world, the dependable operation and tolerance of failures in both cyber and physical components are essential requirements for these systems.The problem of achieving dependable operations for open and networked control systems is approached using a systems engineering process to gain an understanding of the problem domain, since fault tolerance cannot be solved only as a software problem due to the nature of CPSs, which includes close coordination among hardware, software and physical objects. The research methodology consists of developing a concept design, implementing prototypes, and empirically testing the prototypes. Even though modularity has been acknowledged as a key element of fault tolerance, the fault tolerance of highly modular service-oriented architectures (SOAs) has been sparsely researched, especially in distributed real-time systems. This thesis proposes and implements an approach based on using loosely coupled real-time SOA to implement fault tolerance for a teleoperation system.Based on empirical experiments, modularity on a service level can be used to support fault tolerance (i.e., the isolation and recovery of faults). Fault recovery can be achieved for certain categories of faults (i.e., non-deterministic and aging-related) based on loose coupling and diverse operation modes. The proposed architecture also supports the straightforward integration of fault tolerance patterns, such as FAIL-SAFE, HEARTBEAT, ESCALATION and SERVICE MANAGER, which are used in the prototype systems to support dependability requirements. For service failures, systems rely on fail-safe behaviours, diverse modes of operation and fault escalation to backup services. Instead of using time-bounded reconfiguration, services operate in best-effort capabilities, providing resilience for the system. This enables, for example, on-the-fly service changes, smooth recoveries from service failures and adaptations to new computing environments, which are essential requirements for CPSs.The results are combined into a systems engineering approach to dependability, which includes an analysis of the role of safety-critical requirements for control system software architecture design, architectural design, a dependability-case development approach for CPSs and domain-specific fault taxonomies, which support dependability case development and system reliability analyses. Other contributions of this work include three new patterns for fault tolerance in CPSs: DATA-CENTRIC ARCHITECTURE, LET IT CRASH and SERVICE MANAGER. These are presented together with a pattern language that shows how they relate to other patterns available for the domain

Semantic multi-criteria decision making in autonomous embedded systems

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Simulating social relations in multi-agent systems

Open distributed systems are comprised of a large number of heterogeneous nodes with disparate requirements and objectives, a number of which may not conform to the system specification. This thesis argues that activity in such systems can be regulated by using distributed mechanisms inspired by social science theories regarding similarity /kinship, trust, reputation, recommendation and economics. This makes it possible to create scalable and robust agent societies which can adapt to overcome structural impediments and provide inherent defence against malicious and incompetent action, without detriment to system functionality and performance. In particular this thesis describes: • an agent based simulation and animation platform (PreSage), which offers the agent developer and society designer a suite of powerful tools for creating, simulating and visualising agent societies from both a local and global perspective. • a social information dissemination system (SID) based on principles of self organisation which personalises recommendation and directs information dissemination. • a computational socio-cognitive and economic framework (CScEF) which integrates and extends socio-cognitive theories of trust, reputation and recommendation with basic economic theory. • results from two simulation studies investigating the performance of SID and the CScEF. The results show the production of a generic, reusable and scalable platform for developing and animating agent societies, and its contribution to the community as an open source tool. Secondly specific results, regarding the application of SID and CScEF, show that revealing outcomes of using socio-technical mechanisms to condition agent interactions can be demonstrated and identified by using Presage.Open Acces

SERVICE-BASED AUTOMATION OF SOFTWARE CONSTRUCTION ACTIVITIES

The reuse of software units, such as classes, components and services require professional knowledge to be performed. Today a multiplicity of different software unit technologies, supporting tools, and related activities used in reuse processes exist. Each of these relevant reuse elements may also include a high number of variations and may differ in the level and quality of necessary reuse knowledge. In such an environment of increasing variations and, therefore, an increasing need for knowledge, software engineers must obtain such knowledge to be able to perform software unit reuse activities. Today many different reuse activities exist for a software unit. Some typical knowledge intensive activities are: transformation, integration, and deployment. In addition to the problem of the amount of knowledge required for such activities, other difficulties also exist. The global industrial environment makes it challenging to identify sources of, and access to, knowledge. Typically, such sources (e.g., repositories) are made to search and retrieve information about software unitsand not about the required reuse activity knowledge for a special unit. Additionally, the knowledge has to be learned by inexperienced software engineers and, therefore, to be interpreted. This interpretation may lead to variations in the reuse result and can differ from the estimated result of the knowledge creator. This makes it difficult to exchange knowledge between software engineers or global teams. Additionally, the reuse results of reuse activities have to be repeatable and sustainable. In such a scenario, the knowledge about software reuse activities has to be exchanged without the above mentioned problems by an inexperienced software engineer. The literature shows a lack of techniques to store and subsequently distribute relevant reuse activity knowledge among software engineers. The central aim of this thesis is to enable inexperienced software engineers to use knowledge required to perform reuse activities without experiencing the aforementioned problems. The reuse activities: transformation, integration, and deployment, have been selected as the foundation for the research. Based on the construction level of handling a software unit, these activities are called Software Construction Activities (SCAcs) throughout the research. To achieve the aim, specialised software construction activity models have been created and combined with an abstract software unit model. As a result, different SCAc knowledge is described and combined with different software unit artefacts needed by the SCAcs. Additionally, the management (e.g., the execution of an SCAc) will be provided in a service-oriented environment. Because of the focus on reuse activities, an approach which avoids changing the knowledge level of software engineers and the abstraction view on software units and activities, the object of the investigation differs from other approaches which aim to solve the insufficient reuse activity knowledge problem. The research devised novel abstraction models to describe SCAcs as knowledge models related to the relevant information of software units. The models and the focused environment have been created using standard technologies. As a result, these were realised easily in a real world environment. Softwareengineers were able to perform single SCAcs without having previously acquired the necessary knowledge. The risk of failing reuse decreases because single activities can be performed. The analysis of the research results is based on a case study. An example of a reuse environmenthas been created and tested in a case study to prove the operational capability of the approach. The main result of the research is a proven concept enabling inexperienced software engineers to reuse software units by reusing SCAcs. The research shows the reduction in time for reuse and a decrease of learning effort is significant

A framework for robust control of uncertainty in self-adaptive software connectors

Context and motivations. The desired behavior of a system in ubiquitous environments considers not only its correct functionality, but also the satisfaction of its non-functional properties, i.e., its quality of service. Given the heterogeneity and dynamism characterizing the ubiquitous environments and the need for continuous satisfaction of non-functional properties, self-adaptive solutions appear to be an appropriate approach to achieve interoperability. In this work, self-adaptation is adopted to enable software connectors to adapt the interaction protocols run by the connected components to let them communicate in a timely manner and with the required level of quality. However, this self-adaptation should be dependable, reliable and resilient to be adopted in dynamic, unpredictable environments with different sources of uncertainty. The majority of current approaches for the construction of self-adaptive software ignore the uncertainty underlying non-functional requirement verification and adaptation reasoning. Consequently, these approaches jeopardize system reliability and hinder the adoption of self-adaptive software in areas where dependability is of utmost importance. Objective. The main objective of this research is to properly handle the uncertainties in the non-functional requirement verification and the adaptation reasoning part of the self-adaptive feedback control loop of software connectors. This will enable a robust and runtime efficient adaptation in software connectors and make them reliable for usage in uncertain environments. Method. In the context of this thesis, a framework has been developed with the following functionalities: 1) Robust control of uncertainty in runtime requirement verification. The main activity in runtime verification is fine-tuning of the models that are adopted for runtime reasoning. The proposed stochastic approach is able to update the unknown parameters of the models at runtime even in the presence of incomplete and noisy observations. 2) Robust control of uncertainty in adaptation reasoning. A general methodology based on type-2 fuzzy logic has been introduced for the control of adaptation decision-making that adjusts the configuration of component connectors to the appropriate mode. The methodology enables a systematic development of fuzzy logic controllers that can derive the right mode for connectors even in the presence of measurement inaccuracy and adaptation policy conflicts. Results. The proposed model evolution mechanism is empirically evaluated, showing a significant precision of parameter estimation with an acceptable overhead at runtime. In addition, the fuzzy based controller, generated by the methodology, has been shown to be robust against uncertainties in the input data, efficient in terms of runtime overhead even in large-scale knowledge bases and stable in terms of control theory properties. We also demonstrate the applicability of the developed framework in a real-world domain. Thesis statement. We enable reliable and dependable self-adaptations of component connectors in unreliable environments with imperfect monitoring facilities and conflicting user opinions about adaptation policies by developing a framework which comprises: (a) mechanisms for robust model evolution, (b) a method for adaptation reasoning, and (c) tool support that allows an end-to-end application of the developed techniques in real-world domains

Dynamic Complex Event Processing for Industrial Monitoring Systems

Using Complex Event Processing (CEP) as part of monitoring systems is a state-of-the-art approach in the manufacturing industry that still requires development. The industry is increasingly moving towards implementing Service Oriented Architecture (SOA) based systems to respond to increasing demands of interoperability amongst other operations in a business organisation. Complex event processors are used as part of monitoring systems but current complex event processors are usually system specific. This thesis aims to propose and demonstrate a more dynamic approach for implementing an industrial monitoring system using complex event processing. Service Oriented Architecture uses event-based messaging to communicate between different devices and systems. This creates large amounts of data in the monitored system. In order to infer important information from this vast body of data the CEP is used to query through the events. These queries are predefined and cannot be changed during runtime. The CEP holds the main logic of the monitoring system and thus dictates what the system actually monitors. Monitoring system requires the possibility to change the monitoring logic. This is why a method of dynamically adding queries will be proposed in this thesis. In order for a SOA-based monitoring system to be dynamic the CEP needs to be dynamic. This thesis proposes a CEP solution with generic implementation, dynamic query definition during runtime and the possibility to use recursive user defined functions that allow reusing query templates in different solutions. The developed CEP is tested with two different implementation use cases. First one a simulated use case that tests the monitoring system performance with large amounts of events. Second one a manufacturing line implementation to demonstrate the monitoring system in an actual manufacturing environment. Tests were run on both use cases to gain information on how the CEP performs and to demonstrate the functionality of the developed monitoring system. The developed CEP was used as a part of oil lubrication use case for IMC-AESOP project. IMC-AESOP project was an EU project researching how to apply state-of-the-art SOA-based systems to the industrial automation field