7,675 research outputs found
Architectural design rewriting as an architecture description language
Architectural Design Rewriting (ADR) is a declarative rule-based approach for the design of dynamic software architectures. The key features that make ADR a suitable and expressive framework are the algebraic presentation of graph-based structures and the use of conditional rewrite rules. These features enable the modelling of, e.g. hierarchical design, inductively defined reconfigurations and
ordinary computation. Here, we promote ADR as an Architectural
Description Language
Style-Based architectural reconfigurations
We introduce Architectural Design Rewriting (ADR), an approach to the design of reconfigurable software architectures whose key features are: (i) rule-based approach (over graphs); (ii) hierarchical design; (iii) algebraic presentation; and (iv) inductively-defined reconfigurations. Architectures are modelled by graphs whose edges and nodes represent components and connection ports. Architectures are designed hierarchically by a set of edge replacement rules that fix the architectural style. Depending on their reading, productions allow: (i) top-down design by refinement, (ii) bottom-up typing of actual architectures, and (iii) well-formed composition of architectures. The key idea is to encode style proofs as terms and to exploit such information at run-time for guiding reconfigurations. The main advantages of ADR
are that: (i) instead of reasoning on flat architectures, ADR specifications provide a convenient hierarchical structure, by exploiting the architectural classes introduced by the style, (ii) complex reconfiguration schemes can be defined inductively, and (iii) style-preservation is guaranteed
Ten virtues of structured graphs
This paper extends the invited talk by the first author about the virtues
of structured graphs. The motivation behind the talk and this paper relies on our
experience on the development of ADR, a formal approach for the design of styleconformant,
reconfigurable software systems. ADR is based on hierarchical graphs
with interfaces and it has been conceived in the attempt of reconciling software architectures
and process calculi by means of graphical methods. We have tried to
write an ADR agnostic paper where we raise some drawbacks of flat, unstructured
graphs for the design and analysis of software systems and we argue that hierarchical,
structured graphs can alleviate such drawbacks
A formal support to business and architectural design for service-oriented systems
Architectural Design Rewriting (ADR) is an approach for the design of software architectures developed within Sensoria by reconciling graph transformation and process calculi techniques. The key feature that makes ADR a suitable and expressive framework is the algebraic handling of structured graphs, which improves the support for specification, analysis and verification of service-oriented architectures and applications. We show how ADR is used as a formal ground for high-level modelling languages and approaches developed within Sensoria
Designing Software Architectures As a Composition of Specializations of Knowledge Domains
This paper summarizes our experimental research and software development activities in designing robust, adaptable and reusable software architectures. Several years ago, based on our previous experiences in object-oriented software development, we made the following assumption: ‘A software architecture should be a composition of specializations of knowledge domains’. To verify this assumption we carried out three pilot projects. In addition to the application of some popular domain analysis techniques such as use cases, we identified the invariant compositional structures of the software architectures and the related knowledge domains. Knowledge domains define the boundaries of the adaptability and reusability capabilities of software systems. Next, knowledge domains were mapped to object-oriented concepts. We experienced that some aspects of knowledge could not be directly modeled in terms of object-oriented concepts. In this paper we describe our approach, the pilot projects, the experienced problems and the adopted solutions for realizing the software architectures. We conclude the paper with the lessons that we learned from this experience
Supporting Management lnteraction and Composition of Self-Managed Cells
Management in ubiquitous systems cannot rely on human intervention or centralised
decision-making functions because systems are complex and devices
are inherently mobile and cannot refer to centralised management applications
for reconfiguration and adaptation directives. Management must be devolved,
based on local decision-making and feedback control-loops embedded in autonomous
components. Previous work has introduced a Self-Managed Cell (SMC)
as an infrastructure for building ubiquitous applications. An SMC consists
of a set of hardware and software components that implement a policy-driven
feedback control-loop. This allows SMCs to adapt continually to changes in
their environment or in their usage requirements. Typical applications include
body-area networks for healthcare monitoring, and communities of unmanned
autonomous vehicles (UAVs) for surveillance and reconnaissance operations.
Ubiquitous applications are typically formed from multiple interacting autonomous
components, which establish peer-to-peer collaborations, federate and
compose into larger structures. Components must interact to distribute management
tasks and to enforce communication strategies. This thesis presents
an integrated framework which supports the design and the rapid establishment
of policy-based SMC interactions by systematically composing simpler abstractions
as building elements of a more complex collaboration. Policy-based
interactions are realised – subject to an extensible set of security functions –
through the exchanges of interfaces, policies and events, and our framework
was designed to support the specification, instantiation and reuse of patterns of
interaction that prescribe the manner in which these exchanges are achieved.
We have defined a library of patterns that provide reusable abstractions for
the structure, task-allocation and communication aspects of an interaction,
which can be individually combined for building larger policy-based systems in
a methodical manner. We have specified a formal model to ensure the rigorous
verification of SMC interactions before policies are deployed in physical devices.
A prototype has been implemented that demonstrates the practical feasibility
of our framework in constrained resources
Современные аспекты и анализ использования орнамента в архитектуре Казахстана
This article discusses modern state of usage of national ornament in architecture of Kazakhstan.В статье рассматривается современное состояние использования национального орнамента в архитектуре Казахстана
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