Towards guidelines for building a business case and gathering evidence of software reference architectures in industry

Background: Software reference architectures are becoming widely adopted by organizations that need to support the design and maintenance of software applications of a shared domain. For organizations that plan to adopt this architecture-centric approach, it becomes fundamental to know the return on investment and to understand how software reference architectures are designed, maintained, and used. Unfortunately, there is little evidence-based support to help organizations with these challenges. Methods: We have conducted action research in an industry-academia collaboration between the GESSI research group and everis, a multinational IT consulting firm based in Spain. Results: The results from such collaboration are being packaged in order to create guidelines that could be used in similar contexts as the one of everis. The main result of this paper is the construction of empirically-grounded guidelines that support organizations to decide on the adoption of software reference architectures and to gather evidence to improve RA-related practices. Conclusions: The created guidelines could be used by other organizations outside of our industry-academia collaboration. With this goal in mind, we describe the guidelines in detail for their use.Peer ReviewedPostprint (published version

Research in software allocation for advanced manned mission communications and tracking systems

An assessment of the planned processing hardware and software/firmware for the Communications and Tracking System of the Space Station Freedom (SSF) was performed. The intent of the assessment was to determine the optimum distribution of software/firmware in the processing hardware for maximum throughput with minimum required memory. As a product of the assessment process an assessment methodology was to be developed that could be used for similar assessments of future manned spacecraft system designs. The assessment process was hampered by changing requirements for the Space Station. As a result, the initial objective of determining the optimum software/firmware allocation was not fulfilled, but several useful conclusions and recommendations resulted from the assessment. It was concluded that the assessment process would not be completely successful for a system with changing requirements. It was also concluded that memory requirements and hardware requirements were being modified to fit as a consequence of the change process, and although throughput could not be quantitized, potential problem areas could be identified. Finally, inherent flexibility of the system design was essential for the success of a system design with changing requirements. Recommendations resulting from the assessment included development of common software for some embedded controller functions, reduction of embedded processor requirements by hardwiring some Orbital Replacement Units (ORUs) to make better use of processor capabilities, and improvement in communications between software development personnel to enhance the integration process. Lastly, a critical observation was made regarding the software integration tasks did not appear to be addressed in the design process to the degree necessary for successful satisfaction of the system requirements

Critique of Architectures for Long-Term Digital Preservation

Evolving technology and fading human memory threaten the long-term intelligibility of many kinds of documents. Furthermore, some records are susceptible to improper alterations that make them untrustworthy. Trusted Digital Repositories (TDRs) and Trustworthy Digital Objects (TDOs) seem to be the only broadly applicable digital preservation methodologies proposed. We argue that the TDR approach has shortfalls as a method for long-term digital preservation of sensitive information. Comparison of TDR and TDO methodologies suggests differentiating near-term preservation measures from what is needed for the long term. TDO methodology addresses these needs, providing for making digital documents durably intelligible. It uses EDP standards for a few file formats and XML structures for text documents. For other information formats, intelligibility is assured by using a virtual computer. To protect sensitive information—content whose inappropriate alteration might mislead its readers, the integrity and authenticity of each TDO is made testable by embedded public-key cryptographic message digests and signatures. Key authenticity is protected recursively in a social hierarchy. The proper focus for long-term preservation technology is signed packages that each combine a record collection with its metadata and that also bind context—Trustworthy Digital Objects.

Consciosusness in Cognitive Architectures. A Principled Analysis of RCS, Soar and ACT-R

This report analyses the aplicability of the principles of consciousness developed in the ASys project to three of the most relevant cognitive architectures. This is done in relation to their aplicability to build integrated control systems and studying their support for general mechanisms of real-time consciousness.\ud To analyse these architectures the ASys Framework is employed. This is a conceptual framework based on an extension for cognitive autonomous systems of the General Systems Theory (GST).\ud A general qualitative evaluation criteria for cognitive architectures is established based upon: a) requirements for a cognitive architecture, b) the theoretical framework based on the GST and c) core design principles for integrated cognitive conscious control systems

Managing knowledge in the context of sustainable construction

The 21st century has been a growing awareness of the importance of the sustainability agenda. Moreover for construction, it has become increasingly important as clients are pushing for a more sustainable product to complement their organisations’ own strategic plans. Sustainable development can be defined as development that meets the needs of the present without compromising the ability of future generations to meet their needs. Sustainable construction is therefore seen as the application of sustainable practices to the activities of the construction sector. One of the key factors in making construction projects more sustainable is overcoming the obstacles of capturing and managing the knowledge required by project teams to effect such change. Managing this knowledge is key to the construction industry because of the unique characteristics of its projects, i.e. multi-disciplinary teams, dynamic participation of team members, heavy reliance on previous experiences/heuristics, the one-off nature of the projects, tight schedules, limited budget, etc. Initiatives within the industry and academic research are developing mechanisms and tools for managing knowledge in construction firms and projects. Such work has so far addressed the issues of capturing, storing, and transferring knowledge

A survey on quality attributes in servicebased systems

Service-based systems have become popular in the software industry. In software engineering, it is widely acknowledged that requirements on quality attributes (e.g., performance, security, reliability) significantly impact the design of software systems. This study explores the role of quality attributes during the design of service-based systems. We investigate the significance of quality attributes when designing service-based systems and how quality attributes are addressed through design decisions, across application domains, and related to other aspects of software development, e.g., architecture documentation. We conducted a descriptive survey. The survey was done as an online questionnaire targeting practitioners. Furthermore, we included researchers with practical design experience. We obtained 56 valid responses. Most survey participants consider quality attributes and functionality as equally important and treat quality attributes explicitly rather than implicitly. Furthermore, dependability is the most relevant quality attribute in service-based systems; we do not find quality attributes that are particularly important in specific application domains. Most quality attributes are addressed by ad hoc decisions, rather than established architecture or design patterns or technologies. Only few decision alternatives are considered when making architectural decisions to address quality attributes. Our results partially confirm anecdotal evidence from current literature, but also strengthen previous claims by providing empirical evidence. Our results point to future research directions (e.g., exploring the impact of decision types on how well quality attributes can be achieved) and implications for practitioners (e.g., training makes a difference to how quality attributes are treated).Peer ReviewedPostprint (author’s final draft

Space Generic Open Avionics Architecture (SGOAA) reference model technical guide

This report presents a full description of the Space Generic Open Avionics Architecture (SGOAA). The SGOAA consists of a generic system architecture for the entities in spacecraft avionics, a generic processing architecture, and a six class model of interfaces in a hardware/software system. The purpose of the SGOAA is to provide an umbrella set of requirements for applying the generic architecture interface model to the design of specific avionics hardware/software systems. The SGOAA defines a generic set of system interface points to facilitate identification of critical interfaces and establishes the requirements for applying appropriate low level detailed implementation standards to those interface points. The generic core avionics system and processing architecture models provided herein are robustly tailorable to specific system applications and provide a platform upon which the interface model is to be applied