Vincenzo De Florio

Promises and Challenges of Ambient Assisted Living Systems

The population of elderly people keeps increasing rapidly, which becomes a predominant aspect of our societies. As such, solutions both efficacious and cost-effective need to be sought. Ambient Assisted Living (AAL) is a new approach which promises to address the needs from elderly people. Ambient Intelligence technologies are widely developed in this domain aiming to construct safe environments around assisted peoples and help them maintain independent living. However, there are still many fundamental issues in AAL that remain open. Most of the current efforts still do not fully express the power of human being, and the importance of social connections and social activities is less noticed. Our conjecture is that such features are fundamental prerequisites towards truly effective AAL services. This paper reviews the current status of researches on AAL, discusses the promises and possible advantages of AAL, and also indicates the challenges we must meet in order to develop practical and efficient AAL systems for elderly people. In this paper, we also propose an approach to construct effective home-care system for the elderly people.

The missing ones: Key ingredients towards effective ambient assisted living systems

The population of elderly people keeps increasing rapidly in the past decades, which becomes a predominant aspect of our societies. As such, solutions both efficacious and cost-effective need to be sought. Ambient Assisted Living (AAL) is a new approach which promises to address the needs from elderly people. In this paper, we claim that human participation is a key ingredient towards effective AAL systems, which not only saves social resources, but also has positive influence on the psychological health of the elderly people. Challenges in increasing human participation in ambient assisted living are dis-cussed in this paper and solutions to meet those challenges are also proposed. We use our proposed mutual assistance commu-nity, which is built with service oriented architecture, as an example to demonstrate how to integrate human tasks in AAL sys-tems. Our preliminary simulation results are presented, which support the effectiveness of human participation.

A survey of linguistic structures for application-level fault tolerance

Structures for the expression of fault-tolerance provisions in application software comprise the central topic of this article. Structuring techniques answer questions as to how to incorporate fault tolerance in the application layer of a computer program and how to manage the fault-tolerant code. As such, they provide the means to control complexity, the latter being a relevant factor for the introduction of design faults. This fact and the ever-increasing complexity of todays distributed software justify the need for simple, coherent, and effective structures for the expression of fault-tolerance in the application software. In this text we first define a “base” of structural attributes with which application-level fault-tolerance structures can be qualitatively assessed and compared with each other and with respect to the aforementioned needs. This result is then used to provide an elaborated survey of the state-of-the-art of application-level fault-tolerance structures.

Antifragility = Elasticity + Resilience + Machine Learning Models and Algorithms for Open System Fidelity☆

Abstract We introduce a model of the fidelity of open systems—fidelity being interpreted here as the compliance between corresponding figures of interest in two separate but communicating domains. A special case of fidelity is given by real-timeliness and synchrony, in which the figure of interest is the physical and the systems notion of time. Our model covers two orthogonal aspects of fidelity, the first one focusing on a systems steady state and the second one capturing that systems dynamic and behavioural characteristics. We discuss how the two aspects correspond respectively to elasticity and resilience and we highlight each aspects qualities and limitations. Finally we sketch the elements of a new model coupling both of the first models aspects and complementing them with machine learning. Finally, a conjecture is put forward that the new model may represent a first step towards compositional criteria for antifragile systems.

Toward architecture-based context-aware deployment and adaptation

Software systems are increasingly expected to dynamically self-adapt to the changing environments. One of the main adaptation mechanisms is dynamic recomposition of application components. This paper addresses the key issues that arise when context knowledge is used to steer the run-time (re)composition process so as to match the new environmental conditions. In order to integrate such knowledge into this process, A Continuous Context-Aware Deployment and Adaptation (ACCADA) framework is proposed. To support run-time component composition, the essential runtime abstractions of the underlying component model are studied. By using a layered modeling approach, our framework gradually incorporates design-time as well as run-time knowledge into the component composition process. Service orientation is employed to facilitate the changes of adaptation policy. Results show that our framework has significant advantages over traditional approaches in light of flexibility, resource usage and lines of code. Although our experience was based on the OSGi middleware, we believe our findings to be general to architecture-based management systems using reflective component models.

On the Constituent Attributes of Software and Organizational Resilience

Our societies are increasingly dependent on the services supplied by our computers and their software. Forthcoming new technology is only exacerbating this dependence by increasing the number, the performance, and the degree of autonomy and inter-connectivity of software-empowered computers and cyber-physical “things”, which translates into unprecedented scenarios of interdependence. As a consequence, guaranteeing the persistence-of-identity of individual and collective software systems and software-backed organisations becomes an increasingly important prerequisite towards sustaining the safety, security, and quality of the computer services supporting human societies. Resilience is the term used to refer to the ability of a system to retain its functional and non-functional identity. In the present article we conjecture that a better understanding of resilience may be reached by decomposing it into a number of ancillary constituent properties, the same way as a better insight in system dependability was obtained by breaking it down into safety, availability, reliability, and other sub-properties. Three of the main sub-properties of resilience proposed here refer respectively to the ability to perceive environmental changes; to understand the implications introduced by those changes; and to plan and enact adjustments intended to improve the system-environment fit. A fourth property characterises the way the above abilities manifest themselves in computer systems. The four properties are then analyzed in three families of case studies, each consisting of three software systems that embed different resilience methods. Our major conclusion is that reasoning in terms of our resilience sub-properties may help revealing the characteristics—and in particular the limitations—of classic methods and tools meant to achieve system and organisational resilience. We conclude by suggesting that our method may prelude to meta-resilient systems— systems, that is, able to adjust optimally their own resilience with respect to changing environmental conditions.Abstract The conjecture is put forward that a better understanding of resilience may be reached by decomposing it into a number of ancillary constituent properties, in the same way as a better insight into system dependability was obtained by breaking it down into safety, availability, reliability, and other sub-properties. Three of the main sub-properties of resilience proposed here refer respectively to the ability to perceive environmental changes; to understand the implications introduced by those changes; and to plan and enact adjustments intended to improve the system–environment fit. A fourth property characterizes the way the above abilities manifest themselves in computer systems. The four properties are then analyzed in three families of case studies, each consisting of three software systems that embed different resilience methods. Our major conclusion is that reasoning in terms of our resilience sub-properties may help reveal the characteristics and, in particular, the limitations of classic methods and tools meant to achieve system and organizational resilience. It is suggested that this method may be a prelude to meta-resilient systems, which are able to adjust optimally their own resilience with respect to changing environmental conditions.

A hybrid real-time component model for reconfigurable embedded systems

Increasing capabilities of modern microcontrollers greatly increase their applicability to more and more unstable and complex environments. Dynamic reconfiguration provides a powerful mechanism to adapt in such environments. However, the implementation of dynamic reconfiguration is still challenging for embedded real-time control software systems. In this paper, we present our real-time component framework which simultaneously supports hard real-time control and non-real-time adaption management while keeping the implementation as lean as possible. Our contribution is the hybrid component model in which one part is designed to support the real-time task while its non-real-time counterpart deals with component adaptation and management functions. A detailed analysis of the intra-component management interface was provided. XML was employed to describe and configure real-time task. We also designed an interface between real-time objects to achieve an inter-real-time task communication scheme based on global shared memory. In the non real-time domain, by mapping much of the management functions to the OSGi system service, we realized the components management service. Our framework can achieve complex component management while providing hard real-time assurance.

On resilient behaviors in computational systems and environments

The present article introduces a reference framework for discussing resilience of computational systems. Rather than a property that may or may not be exhibited by a system, resilience is interpreted here as the emerging result of a dynamic process. Said process represents the dynamic interplay between the behaviors exercised by a system and those of the environment it is set to operate in. As a result of this interpretation, coherent definitions of several aspects of resilience can be derived and proposed, including elasticity, change tolerance, and antifragility. Definitions are also provided for measures of the risk of unresilience as well as for the optimal match of a given resilient design with respect to the current environmental conditions. Finally, a resilience strategy based on our model is exemplified through a simple scenario.

ACCADA: A Framework for Continuous Context-Aware Deployment and Adaptation

Software systems are increasingly expected to dynamically self-adapt to the changing environments. One of the principle adaptation mechanisms is dynamic recomposition of application components. This paper addresses the key issues that arise when external context knowledge is used to steer the run-time (re)composition process. In order to integrate such knowledge into this process, A Continuous Context-Aware Deployment and Adaptation (ACCADA) framework is proposed. To support run-time component composition, the essential runtime abstractions of the underlying component model are studied. By using a layered modeling approach, our framework gradually incorporates design-time as well as run-time knowledge into the component composition process. Service orientation is employed to facilitate the changes of adaptation policy. Results show that our framework has significant advantages over traditional approaches in light of flexibility, resource usage and lines of code. Although our experience was done based on the OSGi middleware, we believe our findings to be general to other architecture-based management systems.

TIRAN: Flexible and Portable Fault Tolerance Solutions for Cost Effective Dependable Applications

Available solutions for fault tolerance in embedded automation are often based on strong customisation, have impacts on the whole life-cycle, and require highly specialised design teams, thus making dependable embedded systems costly and difficult to develop and maintain. The TIRAN project develops a framework which provides fault tolerance capabilities to automation systems, with the goal of allowing portable, reusable and cost-effective solutions. Application developers are allowed to select, configure and integrate in their own environment a variety of software-based functions for error detection, confinement and recovery provided by the framework.