| 31. |
- Pei-Breivold, Hongyu, et al.
(författare)
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A Survey of Software Architecture Evolvability
- 2009
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- For long-lived systems, there is a need to address evolvability (i.e. a system’s ability to easily accommodate changes) explicitly during the entire lifecycle. In this report, we undertake a systematic review to obtain an overview of the existing studies in promoting software evolvability at architectural level. The search strategy identified 3036 studies, of which 54 were catalogued as primary studies for this review after using multi-step selection process. The studies are classified into five main categories of themes, including techniques that support quality considerations during software architecture design, architectural quality evaluation, economic valuation, architectural knowledge management and modeling techniques. Four dimensions of factors are identified that exert influence on software evolvability. To cope with these diverse influencing factors, combination of appropriate techniques becomes necessary.
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| 32. |
- Pei Breivold, Hongyu
(författare)
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Software Architecture Evolution and Software Evolvability
- 2009
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Software is characterized by inevitable changes and increasing complexity, which in turn may lead to huge costs unless rigorously taking into account change accommodations. This is in particular true for long-lived systems. For such systems, there is a need to address evolvability explicitly during the entire lifecycle, carry out software evolution efficiently and reliably, and prolong the productive lifetime of the software systems. In this thesis, we study evolution of software architecture and investigate ways to support this evolution. The central theme of the thesis is how to analyze software evolvability, i.e. a system’s ability to easily accommodate changes. We focus on several particular aspects: (i) what software characteristics are necessary to constitute an evolvable software system; (ii) how to assess evolvability in a systematic manner; (iii) what impacts need to be considered given a certain change stimulus that results in potential requirements the software architecture needs to adapt to, e.g. ever-changing business requirements and advances of technology. To improve the capability in being able to on forehand understand and analyze systematically the impact of a change stimulus, we introduce a software evolvability model, in which subcharacteristics of software evolvability and corresponding measuring attributes are identified. In addition, a further study of one particular measuring attribute, i.e. modularity, is performed through a dependency analysis case study. We introduce a method for analyzing software evolvability at the architecture level. This is to ensure that the implications of the potential improvement strategies and evolution path of the software architecture are analyzed with respect to the evolvability subcharacteristics. This method is proposed and piloted in an industrial setting. The fact that change stimuli come from both technical and business perspectives spawns two aspects that we also look into in this research, i.e. to respectively investigate the impacts of technology-type and business-type of change stimuli.
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| 33. |
- Pei Breivold, Hongyu
(författare)
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Software Architecture Evolution through Evolvability Analysis
- 2011
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In this thesis, we study evolution of software architecture and investigate ways to support this evolution. The central theme of the thesis is how to analyze software evolvability, i.e., a system’s ability to easily accommodate changes. We focus on two main aspects: (i) what software characteristics are necessary for an evolvable software system; and (ii) how to assess evolvability of long-lived proprietary systems in a systematic manner. A secondary focus is to investigate how evolvability is addressed in open source software evolution. We have performed a systematic review of architecture evolution research, and proposed a software evolvability model, in which subcharacteristics of software evolvability and corresponding measuring attributes are identified. Based on this model, we have proposed the softwarearchitectureevolvabilityanalysis (AREA) process which provides repeatable techniques for supporting software architecture evolution: a) Qualitative evolvability analysis method that focuses on improving the capability of being able to understand and analyze systematically the impact of change stimuli on software architecture evolution; b) Quantitative evolvability analysis method that provides quantifications of stakeholders’ evolvability concerns and potential architectural solutions’ impacts on evolvability. These techniques have been validated in industrial settings of different domains, and can be used as an integral part of software development and evolution process. This is to ensure that the implications of the potential improvement strategies and evolution path of software architectures are analyzed with respect to the evolvability subcharacteristics. As a supplementary research contribution, we have conducted a systematic review of the existing studies in open source software (OSS) evolution, and performed a comprehensive analysis which describes how software evolvability is addressed during the development and evolution of OSS, and identified challenges and future research directions in OSS evolution.
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| 34. |
- Pei-Breivold, Hongyu, et al.
(författare)
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Using Software Evolvability Model for Evolvability Analysis
- 2008
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Software evolution is characterized by inevitable changes of software and increasing software complexities, which in turn may lead to huge costs unless rigorously taking into account change accommodations. This is in particular true for long-lived systems in which changes go beyond maintainability. For such systems, there is a need to address evolvability explicitly in the requirements and early design phases and maintain it during the entire lifecycle. Nevertheless, there is a lack of a model that can be used for analyzing, evaluating and comparing software systems in terms of evolvability. In this paper, we describe the initial establishment of an evolvability model as a framework for analysis of software evolvability. We motivate and exemplify the model through an industrial case study of a software-intensive automation system.
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| 35. |
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| 36. |
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| 37. |
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| 38. |
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| 39. |
- Sapienza, Gaetana
(författare)
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Multiple Property-based Partitioning for Embedded Applications
- 2014
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The new development of different types of computation units, such as FPGAs and multicore CPUs, enables a tremendous improvement in performance of applications that utilize the dedicated types of computations. For complex applications this however introduces a new challenge - what is the optimal deployment configuration of their components?Today the application deployment is based on ad-hoc architectural decisions taken in an early design phase, when many design details are unknown, and as a consequence they often change in a later phase, increasing so the development costs. In addition, the decisions are taken based on a limited number of requirements, mostly related to runtime properties such as performance, resource utilization and power consumption, but do not consider many other aspects related to lifecycle properties, or to the project constraints. This approach increases the risk that a decision has a negative impact on a runtime or a lifecycle system property and may lead to the mentioned changes. This thesis addresses the problem of optimal hardware/software deployment of an application. The main objective is to define a process in which the deployment decisions are taken in a systematic way in a later phase of the design process, and the partition decision process takes into account all artifacts on which the decisions have direct impact. These artifacts include the application’s runtime properties, the properties related to the application lifecycle, the business goals, and the development project constraints. To achieve this objective we have a) defined a development process model that addresses the deployment explicitly in the late design phase, b) designed a metamodel of component-based applications deployed as hardware or software executable units, and c) analyzed the suitability of Multiple Criteria Decision Analysis methods for providing partitioning decisions based on a large number of criteria. In addition we have analysed which properties are affected by the partitioning decisions in the Control and Automation domains. The feasibility of the proposed process is demonstrated throughout an industrial case study.
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| 40. |
- Sapienza, Gaetana, et al.
(författare)
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Technical Report : Modelling for hardware and software deployment based on multiple properties selection
- 2013
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This technical report is an appendix to a paper Gaetana Sapienza, Ivica Crnkovic, Tiberiu Seceleanu, Modelling for hardware and software deployment based on multiple properties selection, 2012 The report contains (1) a full specification of a embedded component-based system model using in MultiPart approach, and (2) a full specification of the Wind Turbine controller model generated by Simulink.
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