Aspect-oriented Approach to Metamodel Abstraction

A software system maintenance represents an important part of software system's lifetime. The most common reasons to change a software system are bug fixes and adding of a new functionality. Software maintenance itself is a difficult and complex process. Before applying a change, it is important to understand the software system's source code as well as the application domain. This paper presents our innovative approach to improve software system comprehension in order to simplify its maintenance. Instead of analyzing all the program code, our approach focuses on parts which are built using predefined well known software libraries. The knowledge of both -- the libraries and the way they are used in software systems -- allows us to identify certain concepts of the software system. This information is used to create metamodels of these concepts. The metamodel is created at a higher level of abstraction than the level of concept implementation

Exploiting persistence in CASE technology

Bibliography: pages 102-107.A Design Workbench has been built for Napier88 [MBC+94] as part of the natural progression towards developing better product systems and improving software construction tools. The system includes a Metamodeller (enabling users to specify the data and process models they prefer), a Model Builder which supports multiple coexisting models and a Target System Generator. Experience using the Workbench has shown that it is easy to use, increases productivity, improves programming standards and facilitates code sharing. This thesis demonstrates the benefits of orthogonal persistence for Computer-Aided Software Engineering by describing an initial design environment and its subsequent extension to include support for multiple co-existing models

A Governance Perspective for System-of-Systems

The operating landscape of 21st century systems is characteristically ambiguous, emergent, and uncertain. These characteristics affect the capacity and performance of engineered systems/enterprises. In response, there are increasing calls for multidisciplinary approaches capable of confronting increasingly ambiguous, emergent, and uncertain systems. System of Systems Engineering (SoSE) is an example of such an approach. A key aspect of SoSE is the coordination and the integration of systems to enable ‘system-of-systems’ capabilities greater than the sum of the capabilities of the constituent systems. However, there is a lack of qualitative studies exploring how coordination and integration are achieved. The objective of this research is to revisit SoSE utility as a potential multidisciplinary approach and to suggest ‘governance’ as the basis for enabling ‘system-of-systems’ coordination and integration. In this case, ‘governance’ is concerned with direction, oversight, and accountability of ‘system-of-systems.’ ‘Complex System Governance’ is a new and novel basis for improving ‘system-of-system’ performance through purposeful design, execution, and evolution of essential metasystem functions.

Contextual Framework of Communications Functions Supporting Complex System Governance

The purpose of this research was to develop a systems theory-based contextual framework of communication functions supporting complex system governance using an inductive research design. Communication, as one aspect of Management Cybernetics (communication and control for effective system organization) constructed of channels of communication, provides for the movement of information internally and externally for a system. This flow reflecting new information, decisions, questions, and intelligence is critical for viability of a system. This research looked for communication mechanisms as developed in system theory, communication theory, management theory, and organizational theory. The literature indicates the importance of communications, but a systemic perspective of communication mechanisms and an effect on the viability of a system are not described. This gap in knowledge was addressed by this research. Specifically, the research looked at the description and system functions serviced by the development of content that flows through the channels of communication. The extensive use of grounded theory method enabled a rigorous inductive analysis of literature dealing with channels of communication. The research produced a construct of communication mechanisms that consists of an integrated grouping of the concepts; Direction, Mode, Product, and Technology (Conveyance). A communication design when developed and/or maintained suggests the communication mechanisms are subject to underlying influences; Identity (motive/intent), Variety Attenuation, Variety Amplification, and Transduction that must be recognized with respect to how Channels of Communication support the viability of the system of interest. While system emergence was not directly related to the Communication Mechanism, the role of Channels of Communication in system emergence is evident as the conduit for the emergence process. Identification of the communication functions means that communication mechanisms, beyond the identification provided by Beer (1979) and Shannon (1948) can be described based in systems theory, communication theory, management theory, knowledge management, and organizational theory. From this construct, a face validation in the form of a survey was conducted. The content of the questionnaire was aligned to the communication mechanisms with the intent to support triangulation. There was peer validation of the questions to the subject of communication, for ease of use and exclusion of private personal information. This was followed by a test run of the survey. The actual accomplishment of the survey was through a web service. This research provides a theoretical construct of communication mechanisms when viewing a system of interest to determining the state of the system channels of communication

Systems Theory-Based Construct for Identifying Metasystem Pathologies for Complex System Governance

The purpose of this research was to develop a systems theory-based construct for metasystem pathologies identification in support of the problem formulation phase of systems-based methodologies using an inductive research design. Problem formulation has been identified as one of the most critical stages in complex system development since it influences later stages in complex system understanding. In modern society where the operating landscape is characteristically ambiguous, mired by complexity, emergence. interdependence, and uncertainty, the concept of problem formulation is used to ensure right issues affecting complex systems surface and addressed to meet expected system performance and viability. In this research, this role of problem formulation is examined in systems-based methodologies in connection with systems theory. While the literature indicates the importance of problem formulation phase in systems-based methodologies. the conceptual foundations of systems theory that form the basis for \u27systemic\u27 thinking in these methodologies is not clearly inculcated into the problem formulation phase. This research addresses this gap by providing the necessary detailed discussion linking systems theory to problem formulation. The research focused on the lack of explicit use of systems theory in problem formulation and metasystemic issues of a higher logical order beyond single system of interest. A rigorous approach employing grounded theory method was used to analyze systems theory (laws, principles, and theorems) in terms of problem formulation to develop a construct – Metasystem Pathologies Identification and derived systems theory-based pathologies (circumstances. conditions, factors, or patterns) that act to limit system performance. A case study was then undertaken to face validate the applicability of emerging systems-theory pathologies in an operational setting were possible utility were developed. Fundamentally, this research presents a new approach to problem formulation where systemic thinking is at the foundation of identifying systemic issues affecting system performance. A significant promise for those interested in problem formulation is the inclusion of systems theory-based pathologies during problem formulation phase of systems-based approaches

Educational use cases from a shared exploration of e-books and iPads

E-books and e-book readers are becoming increasingly widely available, particularly for the general reader, and there have been many studies on their adoption. However, less is known about their use for educational and academic purposes. We report here on work carried out on e-books and e-book applications using iPads by academic and teaching staff. After considering pedagogical issues and reporting survey results, we identify a spiral of six key use case areas for e-books. This spiral of use cases moves from basic e-book use, through situational reading, e-books and learning, using multiple learning resources, collaborative/group learning, to e-book production. We discuss each of these use case areas and provide guidelines that will be of interest to practitioners and researchers alike

The Reflex Sandbox : an experimentation environment for an aspect-oriented Kernel

Reflex es un núcleo versátil para la programación orientada aspectos en Java. Provee de las abstracciones básicas, estructurales y de comportamiento, que permiten implementar una variedad de técnicas orientadas a aspectos. Esta tesis estudia dos tópicos fundamentales. En primer lugar, el desarrollo formal, utilizando el lenguaje Haskell, de las construcciones fundamentales del modelo Reflex para reflexión parcial de comportamiento. Este desarrollo abarca el diseño de un lenguaje, llamado Kernel, el cual es una extensión reflexiva de un lenguaje orientado a objetos simple. La semántica operacional del lenguaje Kernel es presentada mediante una máquina de ejecución abstracta. El otro tópico fundamental que estudia esta tesis es validar que el modelo de reflexión parcial de comportamiento es suficientemente expresivo para proveer de semántica a un subconjunto del lenguaje AspectJ. Con este fin, se desarrolló el Reflex Sandbox: un ambiente de experimentación en Haskell para el modelo Reflex. Tanto el desarrollo formal del modelo de reflexión parcial de comportamiento como la validación del soporte de AspectJ, son estudiados en el contexto del Reflex Sandbox. La validación abarca la definición de un lenguaje orientado a aspectos que caracteriza el enfoque de AspectJ a la programación orientada a aspectos, así como la definición de su máquina de ejecución abstracta. También se presenta un compilador que transforma programas escritos en este lenguaje al lenguaje Kernel. Este proceso de compilación provee los fundamentos para entender como dicha transformación puede ser realizada. El proceso de compilación también fue implementado en Java, pero transformando programas AspectJ a programas Reflex. También se presentan mediciones preliminares del desempeño de un programa compilado y ejecutado en Reflex y un programa compilado, y ejecutado con el compilador AspectJ

Learner-focussed methodology for improving the resilience of training organisations in complex environments

Organisations are increasingly relying on resilience to adapt to uncertain and evolving operational environments, whilst continuing to achieve their requirements, and addressing pathologies in their organisational design and operations. The challenge is exacerbated by the growing organisational complexity, competing priorities and unintended consequences from various system modifications and trade-off decisions. To address the organisational resilience challenges, a comprehensive approach to organisational resilience is required. Despite the proliferation of resilience research in the academic literature, organisational resilience practitioners do not have a holistic practical methodology on how to design and maintain resilience in continuously operating and mature organisations. The research reports its comprehensive approach to ensuring desired organisational performance and resilience characteristics. The key aspects of resilience and organisation are determined in the extensive literature review and key stakeholder engagements, followed by the establishment of the current ‘as is’ state of a Defence training organisation. It is characterised by a mature design, complexity, and the need for uninterrupted delivery of its functions in continuous operations. The research combines resilience conceptualisation and organisational design review outcomes to formulate its approach to the organisational transition from the current ‘as is’ to the future ‘to-be’ state to secure a long-term delivery of the required outputs under diverse stressors. The approach is based on an original resilience framework and architecture; new resilience measures introduced via the survey instrument; and non-traditional application of various system thinking and modelling and simulation methodologies to review and modify a mature and fully operational training organisation targeting resilience. The approach was applied in more than 20 Defence training establishments at different levels of aggregation over three years and reported indicative results and real benefits to the participating organisations, as well as research limitations, contributions, and continuous improvement strategies. Although a Defence training organisation context is used in this paper, the principles of the research approach may be applied to any organisation. Future research directions concern further quantification of organisational resilience aspects such as their interrelationships effect on organisational performance and organisational importance ratings; expanding the scope of organisational context from training to include other organisational types; and developing automation approaches for the resilience survey data analysis and reporting

Becoming Artifacts: Medieval Seals, Passports and the Future of Digital Identity

What does a digital identity token have to do with medieval seals? Is the history of passports of any use for enabling the discovery of Internet users\u27 identity when crossing virtual domain boundaries during their digital browsing and transactions? The agility of the Internet architecture and its simplicity of use have been the engines of its growth and success with the users worldwide. As it turns out, there lies also its crux. In effect, Internet industry participants have argued that the critical problem business is faced with on the Internet is the absence of an identity layer from the core protocols of its logical infrastructure. As a result, the cyberspace parallels a global territory without any identification mechanism that is reliable, consistent and interoperable across domains. This dissertation is an investigation of the steps being taken by Internet stakeholders in order to resolve its identity problems, through the lenses of historical instances where similar challenges were tackled by social actors. Social science research addressing the Internet identity issues is barely nascent. Research on identification systems in general is either characterized by a paucity of historical perspective, or scantily references digital technology and online identification processes. This research is designed to bridge that gap. The general question at its core is: How do social actors, events or processes enable the historical emergence of authoritative identity credentials for the public at large? This work is guided by that line of inquiry through three broad historical case studies: first, the medieval experience with seals used as identity tokens in the signing of deeds that resulted in transfers of rights, particularly estate rights; second, comes the modern, national state with its claim to the right to know all individuals on its territory through credentials such as the passport or the national identity card; and finally, viewed from the United States, the case of ongoing efforts to build an online digital identity infrastructure. Following a process-tracing approach to historical case study, this inquiry presents enlightening connections between the three identity frameworks while further characterizing each. We understand how the medieval doctrines of the Trinity and the Eucharist developed by schoolmen within the Church accommodated seals as markers of identity, and we understand how the modern state seized on the term `nationality\u27 - which emerged as late as in the 19th century - to make it into a legal fiction that was critical for its identification project. Furthermore, this investigation brings analytical insights which enable us to locate the dynamics driving the emergence of those identity systems. An ordering of the contributing factors in sequential categories is proposed in a sociohistorical approach to explain the causal mechanisms at work across these large phenomena. Finally this research also proposes historically informed projections of scenarios as possible pathways to the realization of authoritative digital identity. But that is the beginning of yet another story of identity