1,721,047 research outputs found
No Code Anomaly is an Island : Anomaly Agglomeration as Sign of Product Line Instabilities
Full text linkA software product line (SPL) is a set of systems that share common and varying features. To provide large-scale reuse, the components of a SPL should be easy to maintain. Therefore, developers have to identify anomalous code structures – i.e., code anomalies – that are detrimental to the SPL maintain-ability. Otherwise, SPL changes can eventually propagate to seemly-unrelated features and affect various SPL products. Previous work often assume that each code anomaly alone suffices to characterize SPL maintenance problems, though each single anomaly may represent only a partial, insignificant, or even inexistent view of the problem. As a result, previous studies have difficulties in characterizing anomalous structures that indicate SPL maintenance problems. In this pa-per, we study the surrounding context of each anomaly and observe that certain anomalies may be interconnected, thereby forming so-called anomaly agglomerations. We characterize three types of agglomerations in SPL: feature, feature hierarchy, and component agglomeration. Two or more anomalies form an agglomeration when they affect the same SPL structural element, i.e. a feature, a feature hierarchy, or a component. We then investigate to what extent non-agglomerated and agglomerated anomalies represent sources of a specific SPL maintenance problem: instability. We analyze various releases of four feature-oriented SPLs. Our findings suggest that a specific type of agglomeration indicates up to 89% of sources of instability, unlike non-agglomerated anomalies
Consistency checking of runtime feature dependencies in software product lines
No full textFeature dependency is a kind of feature interaction which can be observed in the features that realize the functionality of a software product, and particularly in the features of Software Product Lines (SPLs). In feature modelling for SPLs, common and variable features are organized both in terms of their structural dependencies (e.g., aggregation and specialization) and in terms of their configuration dependencies (e.g., excluded and required). These dependencies are essential but are not sufficient for developing reusable and adaptable SPL components. There are various other types of feature dependencies (e.g., runtime feature dependencies) that are responsible for implementing the behaviour of an end product. The aim of this research is to facilitate a software product line engineer to detect whether the latter types of feature dependencies have been implemented as specified and as intended.
This thesis proposes and evaluates a four-step technique for consistency checking of runtime feature dependencies in SPL artefacts. The four-step process uses a domain-specific language developed for specifying the product line assets (i.e., features, interdependencies among the features and the implementation source code). The proposed technique uses existing reverse engineering techniques to perform a code-to-model transformation. Aspect-oriented (AO) pattern detection algorithms were developed that implement the runtime feature dependencies. The simple detection of AO-patterns does not guarantee that the behaviour is implemented as intended. Model validation constraints are then applied to provide feature dependency related feedback to a product line engineer.
The key contributions of this thesis are: (i) the extension of previous work on the modularization of runtime feature dependencies, by providing a technique for consistency checking of runtime feature dependencies at various abstraction levels, (ii) the theoretical contribution in the form of a model-driven technique based on round-trip engineering (RTE), (iii) a plug-in based prototype realizing the proposed model-driven technique and (iv) a validation mechanism inspired by a technique called mutation testing which is applied using an existing product line case study
Optimization of Product Instantiation using Integer Programming
Full text linkWe show that Integer Programming (IP) can be used as an optimization technique for the instantiation of products of feature models. This is done by showing that the constraints of feature models can be written in linear form. As particular IP technique, we use Gomory cutting planes. We have applied this technique to a test suite of feature models from the literature, and found that the Gomory cutting planes can be used to improve the feature models. We discuss a number of applications: analysis of feature models, resolving configuration errors and optimization of product instantiation
Feature Petri Nets
Full text linkIn software product line (SPL) engineering, formal modelling and verification are critical for managing the inherent complexity of systems with a high degree of variability. The number of products in an SPL can be exponential in the number of features. Therefore, the challenge when modelling SPL lies in analysing and verifying large, complex models efficiently, in order to ensure that all products behave correctly. The choice of a system modelling formalism that is both expressive and well-established is therefore crucial. In this paper we propose two lightweight extensions to Petri nets: Feature Petri Nets provide a framework for modelling and verifying software product lines; and Dynamic Feature Petri Nets provide additional support for modelling dynamic software product lines.sponsorship: EU project FP7-231620 HATS: Highly Adaptable and Trustworthy Software using Formal Methodsstatus: Publishe
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
On the problems with evolving Egemin's software product line
No full textEgemin, an industrial manufacturer of logistic systems is adopting a Software Product Line (SPL) approach to manage the development of their product portfolio. However, due to the intrinsic complexity of the logistic systems and lack of explicitly documented architectural knowledge evolution of the products is error-prone. Faulty updates in crease maintenance costs and harm the company’s reputation. Therefore, Egemin searches for a systematic solution that can improve their SPL evolution strategy.status: Publishe
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