Enhancing dependability through flexible adaptation to changing requirements

This paper describes an architectural approach that facilitates the dynamic adaptation of systems to changing domain rules. The approach relies on 'coordination contracts', a modelling and implementation primitive we have developed for run-time reconfiguration. Our framework includes an engine that, whenever a service is called, checks the domain rules that are applicable and configures the response of the service before proceeding with the call. This approach enhances dependability in two essential ways: on the one hand, it guarantees that system execution is always consistent with the domain logic because service response is configured automatically (i.e., without any need for programmer intervention); on the other hand, it makes it possible for changes to be incorporated into existing domain rules, and from new rules to be created, with little effort, because coordination contracts can be superposed dynamically without having to change neither the client nor the service code. Our approach is illustrated through a case study in financial systems, an area in which dependability arises mainly in the guise of business concerns like adherence to agreed policies and conditions negotiated on a case-by-case basis. We report on an information system that ATX Software developed for a company specialised in recovering bad credit. We show in particular how, by using this framework, we have devised a way of generating rule-dependent SQL code for batch-oriented services

Taming Uncertainty in the Assurance Process of Self-Adaptive Systems: a Goal-Oriented Approach

Goals are first-class entities in a self-adaptive system (SAS) as they guide the self-adaptation. A SAS often operates in dynamic and partially unknown environments, which cause uncertainty that the SAS has to address to achieve its goals. Moreover, besides the environment, other classes of uncertainty have been identified. However, these various classes and their sources are not systematically addressed by current approaches throughout the life cycle of the SAS. In general, uncertainty typically makes the assurance provision of SAS goals exclusively at design time not viable. This calls for an assurance process that spans the whole life cycle of the SAS. In this work, we propose a goal-oriented assurance process that supports taming different sources (within different classes) of uncertainty from defining the goals at design time to performing self-adaptation at runtime. Based on a goal model augmented with uncertainty annotations, we automatically generate parametric symbolic formulae with parameterized uncertainties at design time using symbolic model checking. These formulae and the goal model guide the synthesis of adaptation policies by engineers. At runtime, the generated formulae are evaluated to resolve the uncertainty and to steer the self-adaptation using the policies. In this paper, we focus on reliability and cost properties, for which we evaluate our approach on the Body Sensor Network (BSN) implemented in OpenDaVINCI. The results of the validation are promising and show that our approach is able to systematically tame multiple classes of uncertainty, and that it is effective and efficient in providing assurances for the goals of self-adaptive systems

Developing a distributed electronic health-record store for India

The DIGHT project is addressing the problem of building a scalable and highly available information store for the Electronic Health Records (EHRs) of the over one billion citizens of India

Enhancing Planning-Based Adaptation Middleware with Support for Dependability: a Case Study

Recent evolutions of mobile devices have opened up for new opportunities for building advanced mobile applications. In particular, these applications are capable of discovering and exploiting software and hardware resources that are made available in their environment. A possible approach for supporting these ubiquitous interactions consists in adapting the mobile application to reflect the functionalities that are provided by the environment. However, these approaches often fail in offering a sufficient degree of resilience to potential device, network, and software failures, which are particularly frequent in ubiquitous environments. Therefore, the contribution of this paper is to integrate the dependability concern in the process of mobile applications adaptation. In particular, we propose to reflect dependability mechanisms as alternative configurations for a given application. This reflection allows the planning-based adaptation middleware to automatically decide, based on contextual information, to enable the support for dependability or not

Intelligent Microgrids

Center for Electromechanic

Credit Strategies for Small and Medium-Sized Enterprises Within a Changing Environment

Access to credit in the changing environment is the primary challenge to survival for many small and medium-sized enterprise (SME) owners. The purpose of this multicase study was to understand how seasoned small business leaders in wholesaling and manufacturing in Northwest Arkansas strategically adapted to obtaining access to credit in an environment of bank mergers and acquisitions, disruptive information technology, federal and state regulations, and globalization. The conceptual framework that grounded this study was adaptive leadership and change management. Although, small business leaders prefer to obtain credit from community banks through relationship financing, leaders of SMEs can adapt to the challenges of the changing environment. The data collection process involved face-to-face, onsite, semistructured interviews of 5 participant SME owners selected via purposive sampling throughout the Northwest Arkansas region. Analysis of the transcripts involved coding data into groups using keyword identification and regrouping the data into themes. Themes that emerged from the study included the importance of formalizing a capital strategy, utilizing alternative forms of financing, and responding and adapting to change. Also, small business owners use financial software to provide technical, financial reports, and pro forma statements with variance analysis. Positive social change from the findings of this study may develop through SMEs\u27 potential to increase job provision thereby benefiting workers\u27 families with better employment opportunities, enhancing public infrastructure through greater tax revenues, and generating a long-term, viable, sustainable future to the region\u27s public education through an increased tax base

System Qualities Ontology, Tradespace and Affordability (SQOTA) Project – Phase 4

This task was proposed and established as a result of a pair of 2012 workshops sponsored by the DoD Engineered Resilient Systems technology priority area and by the SERC. The workshops focused on how best to strengthen DoD’s capabilities in dealing with its systems’ non-functional requirements, often also called system qualities, properties, levels of service, and –ilities. The term –ilities was often used during the workshops, and became the title of the resulting SERC research task: “ilities Tradespace and Affordability Project (iTAP).” As the project progressed, the term “ilities” often became a source of confusion, as in “Do your results include considerations of safety, security, resilience, etc., which don’t have “ility” in their names?” Also, as our ontology, methods, processes, and tools became of interest across the DoD and across international and standards communities, we found that the term “System Qualities” was most often used. As a result, we are changing the name of the project to “System Qualities Ontology, Tradespace, and Affordability (SQOTA).” Some of this year’s university reports still refer to the project as “iTAP.”This material is based upon work supported, in whole or in part, by the U.S. Department of Defense through the Office of the Assistant of Defense for Research and Engineering (ASD(R&E)) under Contract HQ0034-13-D-0004.This material is based upon work supported, in whole or in part, by the U.S. Department of Defense through the Office of the Assistant of Defense for Research and Engineering (ASD(R&E)) under Contract HQ0034-13-D-0004

Does your organization have an unhealthy identity?

Issue of study: The Swedish dairy company Vattnadahl is currently going through extensive changes, battling new market demands and internal reorganizations. As a consequence, the organization is facing challenges related to its organizational identity. From a theoretical perspective, organizational identity consists of an internal and an external part that together dynamically construct the identity. In case of an unbalance between the internal and the external part, there is a risk of impairing the organizational health. This effect is not, however, further investigated in existing theory. Purpose: The main purpose of this study is to gain insights into how a temporary disassociation between the internal and the external definition of organizational identity is affecting organizational health. Further, the sub-purpose is to illustrate Vattnadahl in the light of identity dynamics and from this investigate if those with power within an organization have greater influence of the identity balance. Methodology: This study was conducted from a qualitative and inductive approach and was performed as a case study at Vattnadahl. From this, collection and compilation of empirical data at Vattnadahl initiated the study. Subsequently, a literature study was conducted in order to explain the phenomena found at Vattnadahl. Finally, the case company was analyzed from an analytical framework developed by the authors. Conclusions: Summarizing the study, it can be concluded that Vattnadahl has an unbalanced identity strongly influenced by their external image. Consequently, the organization is experiencing the dysfunction of hyper-adaptation, which is affecting their organizational health. This effect can be compiled into six unhealthiness factors; stress, frustration, confusion, lack of pride, anxiety, and lack of initiative. Furthermore, it can be concluded that those with power within Vattnadahl have a greater influence on the identity balance compared to other employees. The thesis also provides a development of the construction of possible dysfunctions occurring from an unbalanced identity, by questioning the existing definitions and nuancing the concepts. The nuancing of the concepts is divided into two perspectives; a stakeholder perspective and a nuanced grading perspective. The stakeholder perspective implies that the dysfunction could differ depending on which stakeholder that is in focus of the analysis. The nuancing grading perspective indicates a possibility for dysfunctions to simultaneously exist, but in different strengths, such as softer or stronger