949 research outputs found
Metamodel Instance Generation: A systematic literature review
Modelling and thus metamodelling have become increasingly important in
Software Engineering through the use of Model Driven Engineering. In this paper
we present a systematic literature review of instance generation techniques for
metamodels, i.e. the process of automatically generating models from a given
metamodel. We start by presenting a set of research questions that our review
is intended to answer. We then identify the main topics that are related to
metamodel instance generation techniques, and use these to initiate our
literature search. This search resulted in the identification of 34 key papers
in the area, and each of these is reviewed here and discussed in detail. The
outcome is that we are able to identify a knowledge gap in this field, and we
offer suggestions as to some potential directions for future research.Comment: 25 page
Automating the Procurement of Web Services
As government agencies and business become more dependent on
web services, software solutions to automate their procurement gain importance.
Current approaches for automating the procurement of web services suffer from
an important drawback: neither uncertainty measures nor non-linear, and complex
relations among parameters can be used by providers to specify quality-ofservice
in offers. In this paper, we look deeply into the roots of this drawback
and present a proposal which overcomes it. The key point to achieve this improvement
has been using the constraint programming as a formal basis, since
it endows the model with a very powerful expressiveness. A XML-based implementation
is presented along with some experimental results and comparisons
with other approaches.Comisión Interministerial de Ciencia y Tecnología TIC 2000–1106–C02–01Ministerio de Ciencia y Tecnología TIC2003-02737-C02-01Ministerio de Ciencia y Tecnología FIT-150100-2001-7
Towards a quantitative alloy
Dissertação de mestrado integrado em Engenharia InformáticaWhen one comes across a new problem that needs to be solved, by abstracting from its associated details
in a simple and concise way through the use of formal methods, one is able to better understand the matter
at hand. Alloy (Jackson, 2012), a declarative specification language based on relational logic, is an example
of an effective modelling tool, allowing high-level specification of potentially very complex systems. However,
along with the irrelevant information, measurable data of the system is often lost in the abstraction as well,
making it not as adequate for certain situations.
The Alloy Analyzer represents the relations under analysis by Boolean matrices. By extending this type of
structure to:
• numeric matrices, over N0
, one is able to work with multirelations, i.e. relations whose arcs are
weighted; each tuple is thus associated with a natural number, which allows reasoning in a similar
fashion as in optimization problems and integer programming techniques;
• left-Stochastic matrices, one is able to model faulty behaviour and other forms of quantitative
information about software systems in a probabilistic way; in particular, this introduces the notion of
a probabilistic contract in software design.
Such an increase in Alloy’s capabilities strengthens its position in the area of formal methods for software
design, in particular towards becoming a quantitative formal method.
This dissertation explores the motivation and importance behind quantitative analysis by studying and
establishing theoretical foundations through categorial approaches to accomplish such reasoning in Alloy.
This starts by reviewing the required tools to support such groundwork and proceeds to the design and
implementation of such a quantitative Alloy extension.
This project aims to promote the evolution of quantitative formal methods by successfully achieving
quantitative abstractions in Alloy, extending its support to these concepts and implementing them in the
Alloy Analyzer.Quando se depara com um novo problema que precisa de ser resolvido, ao abstrair dos seus detalhes
associados de forma simples e concisa recorrendo a métodos formais, é possível compreender melhor
o assunto em questão. Alloy (Jackson, 2012), uma linguagem de especificação declarativa baseada em
lógica relacional, é um exemplo de uma ferramenta de modelação eficaz, possibilitando especificações
de alto-nível de sistemas potencialmente bastante complexos. Contudo, em conjunto com a informação
irrelevante, os dados mensuráveis são muitas vezes também perdidos na abstração, tornando-a não tão
adequada para certas situações.
O Alloy Analyzer representa as relações sujeitas a análise através de matrizes Booleanas. Ao estender
este tipo de estrutura para:
• matrizes numéricas, em N0
, é possível lidar com multirelações, i.e., relações cujos arcos são
pesados; cada tuplo é consequentemente associado a um número natural, o que proporciona uma
linha de raciocínio semelhante à de técnicas de problemas de otimização e de programação inteira;
• matrizes estocásticas, permitindo a modelação de comportamento defeituoso e de outros tipos de
informação quantitativa de sistemas de software probabilisticamente; em particular, é introduzida a
noção de contrato probabilístico em design de software.
Tal aumento às capacidades do Alloy, fortalece a sua posição na área de métodos formais para design de
software, em particular, a caminho de se tornar um método formal quantitativo.
Esta dissertação explora a motivação e a importância subjacente à análise quantitativa, a partir do estudo
e consolidação dos fundamentos teóricos através de abordagens categóricas de forma a conseguir suportar
esse tipo de raciocínio em Alloy. Inicialmente, as ferramentas imprescindíveis para assegurar tal base são
analisadas, passando de seguida ao planeamento e posterior implementação de tal extensão quantitativa
do Alloy.
Este projecto pretende promover a evolução dos métodos formais quantitativos através da concretização de
abstracção quantitativa em Alloy, estendendo a sua base para suportar estes conceitos e assim implementá los no Alloy Analyzer
Automatic Test Generation for Space
The European Space Agency (ESA) uses an engine to perform tests in the Ground
Segment infrastructure, specially the Operational Simulator. This engine uses
many different tools to ensure the development of regression testing
infrastructure and these tests perform black-box testing to the C++ simulator
implementation. VST (VisionSpace Technologies) is one of the companies that
provides these services to ESA and they need a tool to infer automatically
tests from the existing C++ code, instead of writing manually scripts to
perform tests. With this motivation in mind, this paper explores automatic
testing approaches and tools in order to propose a system that satisfies VST
needs
WS-Governance: a Policy Language for SOA Governance
The widespread use of Service Oriented Architectures (SOA) is beginning to create problems derived from the governance of said structures. To date there is not a single effective solution to solve all existing challenges to govern this type of infrastructure. This paper describes the problems encountered when designing a SOA governance solution in a real e-Government scenario. More specifically, we focus on problems related to specification and automated analysis of government policies. We propose a novel SOA governance specification model as a solution to these problems. We have named this model WS-Governance. in order to ease its adoption by SOA practitioners it: i) shares WS-Policy guidelines and is compatible with it, ii) has XML serialization as well as a plain-text one and iii) has a CSP based semantics that provides a precise description as well as facilitating the automation of some editing and WS-Governance related activities such as consistency checking
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