An agent-driven semantical identifier using radial basis neural networks and reinforcement learning

Due to the huge availability of documents in digital form, and the deception possibility raise bound to the essence of digital documents and the way they are spread, the authorship attribution problem has constantly increased its relevance. Nowadays, authorship attribution,for both information retrieval and analysis, has gained great importance in the context of security, trust and copyright preservation. This work proposes an innovative multi-agent driven machine learning technique that has been developed for authorship attribution. By means of a preprocessing for word-grouping and time-period related analysis of the common lexicon, we determine a bias reference level for the recurrence frequency of the words within analysed texts, and then train a Radial Basis Neural Networks (RBPNN)-based classifier to identify the correct author. The main advantage of the proposed approach lies in the generality of the semantic analysis, which can be applied to different contexts and lexical domains, without requiring any modification. Moreover, the proposed system is able to incorporate an external input, meant to tune the classifier, and then self-adjust by means of continuous learning reinforcement.Comment: Published on: Proceedings of the XV Workshop "Dagli Oggetti agli Agenti" (WOA 2014), Catania, Italy, Sepember. 25-26, 201

Searching Design Patterns Fast by Using Tree Traversals

Large software systems need to be modified to remain useful. Changes can be more easily performed when their design has been carefully documented. This paper presents an approach to quickly find design patterns that have been implemented into a software system. The devised solution greatly reduces the performed checks by organising the search for a design pattern as tree traversals, where candidate classes are carefully positioned into trees. By automatically tagging classes with design pattern roles we make it easier for developers to reason with large software systems. Our approach can provide documentation that lets developers understand the role each class is playing, assess the quality of the code, have assistance for refactoring and enhancing the functionalities of the software system.

An Optimization Based Design for Integrated Dependable Real-Time Embedded Systems

Moving from the traditional federated design paradigm, integration of mixedcriticality software components onto common computing platforms is increasingly being adopted by automotive, avionics and the control industry. This method faces new challenges such as the integration of varied functionalities (dependability, responsiveness, power consumption, etc.) under platform resource constraints and the prevention of error propagation. Based on model driven architecture and platform based design’s principles, we present a systematic mapping process for such integration adhering a transformation based design methodology. Our aim is to convert/transform initial platform independent application specifications into post integration platform specific models. In this paper, a heuristic based resource allocation approach is depicted for the consolidated mapping of safety critical and non-safety critical applications onto a common computing platform meeting particularly dependability/fault-tolerance and real-time requirements. We develop a supporting tool suite for the proposed framework, where VIATRA (VIsual Automated model TRAnsformations) is used as a transformation tool at different design steps. We validate the process and provide experimental results to show the effectiveness, performance and robustness of the approach

Fault-tolerant software: dependability/performance trade-offs, concurrency and system support

PhD ThesisAs the use of computer systems becomes more and more widespread in applications that demand high levels of dependability, these applications themselves are growing in complexity in a rapid rate, especially in the areas that require concurrent and distributed computing. Such complex systems are very prone to faults and errors. No matter how rigorously fault avoidance and fault removal techniques are applied, software design faults often remain in systems when they are delivered to the customers. In fact, residual software faults are becoming the significant underlying cause of system failures and the lack of dependability. There is tremendous need for systematic techniques for building dependable software, including the fault tolerance techniques that ensure software-based systems to operate dependably even when potential faults are present. However, although there has been a large amount of research in the area of fault-tolerant software, existing techniques are not yet sufficiently mature as a practical engineering discipline for realistic applications. In particular, they are often inadequate when applied to highly concurrent and distributed software. This thesis develops new techniques for building fault-tolerant software, addresses the problem of achieving high levels of dependability in concurrent and distributed object systems, and studies system-level support for implementing dependable software. Two schemes are developed - the t/(n-l)-VP approach is aimed at increasing software reliability and controlling additional complexity, while the SCOP approach presents an adaptive way of dynamically adjusting software reliability and efficiency aspects. As a more general framework for constructing dependable concurrent and distributed software, the Coordinated Atomic (CA) Action scheme is examined thoroughly. Key properties of CA actions are formalized, conceptual model and mechanisms for handling application level exceptions are devised, and object-based diversity techniques are introduced to cope with potential software faults. These three schemes are evaluated analytically and validated by controlled experiments. System-level support is also addressed with a multi-level system architecture. An architectural pattern for implementing fault-tolerant objects is documented in detail to capture existing solutions and our previous experience. An industrial safety-critical application, the Fault-Tolerant Production Cell, is used as a case study to examine most of the concepts and techniques developed in this research.ESPRIT

Design components

PhD ThesisAlthough it is generally recognised that formal modelling is crucial for ensuring the correctness of software systems, some obstacles to its wider adoption in software engineering persist. One of these is that its productivity is low; another that for modelling techniques and tools to be used efficiently, a broad range of specific skills is required. With the gap between computer performance and engineers’ productivity growing, there is a need to raise the level of abstraction at which development is carried out and off-load much of the routine work done manually today to computers. Formal modelling has all the characteristics required to replace programming and offer higher productivity. Nonetheless, as a branch of software engineering it has yet to be generally accepted. While there is substantial research accumulated in systems analysis and verification, notmuch has been done to foster higher productivity and efficiency of modelling activity. This study puts forward an approach that allows the modeller to encapsulate design ideas and experience in a reusable package. This package, called a design component, can be used in differentways. While a design component is generally intended for constructing a new design using an existing one, we base our approach on a refinement technique. The design encapsulated in the design component is injected into a formal development by formally refining an abstract model. This process is completely automated: the design component is integrated by a tool, with the corresponding correctness proofs also handled automatically. To help us construct design components we consider a number of techniques of transforming models and describing reusable designs. We then introduce the concept ofmodel transformation to encapsulate syntactic rewrite rules used to produce new models. To capture high-level design we introduce the pattern language allowing us to build abstraction and refinement patterns from model transformations. Patterns automate the formal development process and reduce the number of proofs. To help the modeller plan and execute refinement steps, we introduce the concept of themodelling pattern. A modelling pattern combines refinement (or abstraction) patterns with modelling guidelines to form a complete design component

Design components

Although it is generally recognised that formal modelling is crucial for ensuring the correctness of software systems, some obstacles to its wider adoption in software engineering persist. One of these is that its productivity is low; another that for modelling techniques and tools to be used efficiently, a broad range of specific skills is required. With the gap between computer performance and engineers’ productivity growing, there is a need to raise the level of abstraction at which development is carried out and off-load much of the routine work done manually today to computers. Formal modelling has all the characteristics required to replace programming and offer higher productivity. Nonetheless, as a branch of software engineering it has yet to be generally accepted. While there is substantial research accumulated in systems analysis and verification, notmuch has been done to foster higher productivity and efficiency of modelling activity. This study puts forward an approach that allows the modeller to encapsulate design ideas and experience in a reusable package. This package, called a design component, can be used in differentways. While a design component is generally intended for constructing a new design using an existing one, we base our approach on a refinement technique. The design encapsulated in the design component is injected into a formal development by formally refining an abstract model. This process is completely automated: the design component is integrated by a tool, with the corresponding correctness proofs also handled automatically. To help us construct design components we consider a number of techniques of transforming models and describing reusable designs. We then introduce the concept ofmodel transformation to encapsulate syntactic rewrite rules used to produce new models. To capture high-level design we introduce the pattern language allowing us to build abstraction and refinement patterns from model transformations. Patterns automate the formal development process and reduce the number of proofs. To help the modeller plan and execute refinement steps, we introduce the concept of themodelling pattern. A modelling pattern combines refinement (or abstraction) patterns with modelling guidelines to form a complete design component.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

Model-connected safety cases

Regulatory authorities require justification that safety-critical systems exhibit acceptable levels of safety. Safety cases are traditionally documents which allow the exchange of information between stakeholders and communicate the rationale of how safety is achieved via a clear, convincing and comprehensive argument and its supporting evidence. In the automotive and aviation industries, safety cases have a critical role in the certification process and their maintenance is required throughout a system’s lifecycle. Safety-case-based certification is typically handled manually and the increase in scale and complexity of modern systems renders it impractical and error prone.Several contemporary safety standards have adopted a safety-related framework that revolves around a concept of generic safety requirements, known as Safety Integrity Levels (SILs). Following these guidelines, safety can be justified through satisfaction of SILs. Careful examination of these standards suggests that despite the noticeable differences, there are converging aspects. This thesis elicits the common elements found in safety standards and defines a pattern for the development of safety cases for cross-sector application. It also establishes a metamodel that connects parts of the safety case with the target system architecture and model-based safety analysis methods. This enables the semi- automatic construction and maintenance of safety arguments that help mitigate problems related to manual approaches. Specifically, the proposed metamodel incorporates system modelling, failure information, model-based safety analysis and optimisation techniques to allocate requirements in the form of SILs. The system architecture and the allocated requirements along with a user-defined safety argument pattern, which describes the target argument structure, enable the instantiation algorithm to automatically generate the corresponding safety argument. The idea behind model-connected safety cases stemmed from a critical literature review on safety standards and practices related to safety cases. The thesis presents the method, and implemented framework, in detail and showcases the different phases and outcomes via a simple example. It then applies the method on a case study based on the Boeing 787’s brake system and evaluates the resulting argument against certain criteria, such as scalability. Finally, contributions compared to traditional approaches are laid out

Policy-Driven Governance in Cloud Service Ecosystems

Cloud application development platforms facilitate new models of software co-development and forge environments best characterised as cloud service ecosystems. The value of those ecosystems increases exponentially with the addition of more users and third-party services. Growth however breeds complexity and puts reliability at risk, requiring all stakeholders to exercise control over changes in the ecosystem that may affect them. This is a challenge of governance. From the viewpoint of the ecosystem coordinator, governance is about preventing negative ripple effects from new software added to the platform. From the viewpoint of third-party developers and end-users, governance is about ensuring that the cloud services they consume or deliver comply with requirements on a continuous basis. To facilitate different forms of governance in a cloud service ecosystem we need governance support systems that achieve separation of concerns between the roles of policy provider, governed resource provider and policy evaluator. This calls for better modularisation of the governance support system architecture, decoupling governance policies from policy evaluation engines and governed resources. It also calls for an improved approach to policy engineering with increased automation and efficient exchange of governance policies and related data between ecosystem partners. The thesis supported by this research is that governance support systems that satisfy such requirements are both feasible and useful to develop through a framework that integrates Semantic Web technologies and Linked Data principles. The PROBE framework presented in this dissertation comprises four components: (1) a governance ontology serving as shared ecosystem vocabulary for policies and resources; (2) a method for the definition of governance policies; (3) a method for sharing descriptions of governed resources between ecosystem partners; (4) a method for evaluating governance policies against descriptions of governed ecosystem resources. The feasibility and usefulness of PROBE are demonstrated with the help of an industrial case study on cloud service ecosystem governance

Editing Team: Markus Fiedler

and contributions of the FIA community on the important research topics that should be addressed for the Framework Programme 8 research programmes broadly grouped around three main concerns; economic and business interests; societal interests and challenges; technical disruptions and capabilities. The contents of this roadmap originate with the community of researchers working on all aspects of the Future Internet and meet to share and discuss ideas through the Future Internet Assembly through an open consultation of research projects who participate in FIA. This roadmap is primarily concerned with identifying research that can be carried out in the second half of this decade and which will have an impact in 2020 and beyond. By ‘impact ’ we mean will result in products, services, systems, capabilities, that come to market and are available and deployed in that timeframe The approach adopted in this report is to integrate contributions across the entire space of future Internet research with the aim of bringing out the vision for how and where the Internet will make a significant difference in the future and identifying the broad challenges and gaps, and identifying the solutions and research needs in the future. In this report we have summarised and grouped ideas with the aim of identifying the strong themes and consistent challenges that emerge looking acros