1,845 research outputs found

    A thread-tag based semantics for sequence diagrams

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    The sequence diagram is one of the most popular behaviour modelling languages which offers an intuitive and visual way of describing expected behaviour of object-oriented software. Much research work has investigated ways of providing a formal semantics for sequence diagrams. However, these proposed semantics may not properly interpret sequence diagrams when lifelines do not correspond to threads of controls. In this paper, we address this problem and propose a thread-tag based sequence diagram as a solution. A formal, partially ordered multiset based semantics for the thread-tag based sequence diagrams is proposed

    TOWARDS A COMPETITIVE LOW-CARBON ECONOMY: ON FIRMS’ INCENTIVES AND THE ROLE OF PUBLIC RESEARCH

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    This paper considers the prerequisites for implementing a competitive low-carbon economy in the European Union from the point of view of firms’ incentives, the role of policy and the contribution of public research. It suggests that the reduction of the environmental impact of energy can be a new competitiveness factor. Rather than being treated as a constraint and cost-aggravating factor, addressing climate change can offer economic opportunity and contribute to growth. The paper looks at both static (energy efficiency) and dynamic (innovation – new products, processes, technologies or sectors and consumption patterns) dimensions of competitiveness.Economic competitiveness; low-carbon economy; energy; technology; and public research.

    A UML profile to model classifier refinements

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    The refinement technique allows us to capture the relationship between specification and implementation in software developments. The precise documentation of the refinement relations hip makes it possible the traceability of the requirements through the refinement steps. Unfortunately, the standard modelling language UML suffers from a lack of notation to specify complex cases of refinement, which hinders the traceability activities. In this article we present a profile of UML to model Classifier refinements as a composition of elementary refinements, allowing for a more precise syntactical specification of the refinement relationshipII Workshop de Ingeniería de Software y Bases de Datos (WISBD)Red de Universidades con Carreras en Informática (RedUNCI

    Towards a scope management of non-functional requirements in requirements engineering

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    Getting business stakeholders’ goals formulated clearly and project scope defined realistically increases the chance of success for any application development process. As a consequence, stakeholders at early project stages acquire as much as possible knowledge about the requirements, their risk estimates and their prioritization. Current industrial practice suggests that in most software projects this scope assessment is performed on the user’s functional requirements (FRs), while the non-functional requirements (NFRs) remain, by and large, ignored. However, the increasing software complexity and competition in the software industry has highlighted the need to consider NFRs as an integral part of software modeling and development. This paper contributes towards harmonizing the need to build the functional behavior of a system with the need to model the associated NFRs while maintaining a scope management for NFRs. The paper presents a systematic and precisely defined model towards an early integration of NFRs within the requirements engineering (RE). Early experiences with the model indicate its ability to facilitate the process of acquiring the knowledge on the priority and risk of NFRs

    Experimental investigation of transverse spin asymmetries in muon-p SIDIS processes: Collins asymmetries

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    The COMPASS Collaboration at CERN has measured the transverse spin azimuthal asymmetry of charged hadrons produced in semi-inclusive deep inelastic scattering using a 160 GeV positive muon beam and a transversely polarised NH_3 target. The Collins asymmetry of the proton was extracted in the Bjorken x range 0.003<x<0.7. These new measurements confirm with higher accuracy previous measurements from the COMPASS and HERMES collaborations, which exhibit a definite effect in the valence quark region. The asymmetries for negative and positive hadrons are similar in magnitude and opposite in sign. They are compatible with model calculations in which the u-quark transversity is opposite in sign and somewhat larger than the d-quark transversity distribution function. The asymmetry is extracted as a function of Bjorken xx, the relative hadron energy zz and the hadron transverse momentum p_T^h. The high statistics and quality of the data also allow for more detailed investigations of the dependence on the kinematic variables. These studies confirm the leading-twist nature of the Collins asymmetry.Comment: 11 pages, 5 figure

    Extending UML templates towards flexibility

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    UML templates are generic model elements that may be instantiated as domain specific solutions by means of parameterization. Some of the elements in a template definition are marked as parameters, implying that these must be sub-stituted by elements of the domain model, so to get a fully functional instance of the template. On parameter substitutions, UML enforces that the parame-tered element and its substitute must be of the same kind (both classes, both at-tributes, etc.). This paper shows that this constraint confines the applicability of templates and proposes an alternative that, by allowing substitutions among elements of different kinds, broadens that applicability. Cross-kind substitu-tions, however, require adequate semantics for the Binding relationship. Such semantics are proposed as model transformations that must complement the plain substitutions preconized by UML. Examples of such transformations are provided for activities in a template being expanded into a bound element.info:eu-repo/semantics/publishedVersio

    Incremental Consistency Checking in Delta-oriented UML-Models for Automation Systems

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    Automation systems exist in many variants and may evolve over time in order to deal with different environment contexts or to fulfill changing customer requirements. This induces an increased complexity during design-time as well as tedious maintenance efforts. We already proposed a multi-perspective modeling approach to improve the development of such systems. It operates on different levels of abstraction by using well-known UML-models with activity, composite structure and state chart models. Each perspective was enriched with delta modeling to manage variability and evolution. As an extension, we now focus on the development of an efficient consistency checking method at several levels to ensure valid variants of the automation system. Consistency checking must be provided for each perspective in isolation, in-between the perspectives as well as after the application of a delta.Comment: In Proceedings FMSPLE 2016, arXiv:1603.0857
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