291 research outputs found

    Transformation by example

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    La transformation de modèles consiste à transformer un modèle source en un modèle cible conformément à des méta-modèles source et cible. Nous distinguons deux types de transformations. La première est exogène où les méta-modèles source et cible représentent des formalismes différents et où tous les éléments du modèle source sont transformés. Quand elle concerne un même formalisme, la transformation est endogène. Ce type de transformation nécessite généralement deux étapes : l’identification des éléments du modèle source à transformer, puis la transformation de ces éléments. Dans le cadre de cette thèse, nous proposons trois principales contributions liées à ces problèmes de transformation. La première contribution est l’automatisation des transformations des modèles. Nous proposons de considérer le problème de transformation comme un problème d'optimisation combinatoire où un modèle cible peut être automatiquement généré à partir d'un nombre réduit d'exemples de transformations. Cette première contribution peut être appliquée aux transformations exogènes ou endogènes (après la détection des éléments à transformer). La deuxième contribution est liée à la transformation endogène où les éléments à transformer du modèle source doivent être détectés. Nous proposons une approche pour la détection des défauts de conception comme étape préalable au refactoring. Cette approche est inspirée du principe de la détection des virus par le système immunitaire humain, appelée sélection négative. L’idée consiste à utiliser de bonnes pratiques d’implémentation pour détecter les parties du code à risque. La troisième contribution vise à tester un mécanisme de transformation en utilisant une fonction oracle pour détecter les erreurs. Nous avons adapté le mécanisme de sélection négative qui consiste à considérer comme une erreur toute déviation entre les traces de transformation à évaluer et une base d’exemples contenant des traces de transformation de bonne qualité. La fonction oracle calcule cette dissimilarité et les erreurs sont ordonnées selon ce score. Les différentes contributions ont été évaluées sur d’importants projets et les résultats obtenus montrent leurs efficacités.Model transformations take as input a source model and generate as output a target model. The source and target models conform to given meta-models. We distinguish between two transformation categories. Exogenous transformations are transformations between models expressed using different languages, and the whole source model is transformed. Endogenous transformations are transformations between models expressed in the same language. For endogenous transformations, two steps are needed: identifying the source model elements to transform and then applying the transformation on them. In this thesis, we propose three principal contributions. The first contribution aims to automate model transformations. The process is seen as an optimization problem where different transformation possibilities are evaluated and, for each possibility, a quality is associated depending on its conformity with a reference set of examples. This first contribution can be applied to exogenous as well as endogenous transformation (after determining the source model elements to transform). The second contribution is related precisely to the detection of elements concerned with endogenous transformations. In this context, we present a new technique for design defect detection. The detection is based on the notion that the more a code deviates from good practice, the more likely it is bad. Taking inspiration from artificial immune systems, we generate a set of detectors that characterize the ways in which a code can diverge from good practices. We then use these detectors to determine how far the code in the assessed systems deviates from normality. The third contribution concerns transformation mechanism testing. The proposed oracle function compares target test cases with a base of examples containing good quality transformation traces, and assigns a risk level based on the dissimilarity between the two. The traces help the tester understand the origin of an error. The three contributions are evaluated with real software projects and the obtained results confirm their efficiencies

    Deviance from perfection is a better criterion than closeness to evil when identifying risky code

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    ABSTRACT We propose an approach for the automatic detection of potential design defects in code. The detection is based on the notion that the more code deviates from good practices, the more likely it is bad. Taking inspiration from artificial immune systems, we generated a set of detectors that characterize different ways that a code can diverge from good practices. We then used these detectors to measure how far code in assessed systems deviates from normality. We evaluated our approach by finding potential defects in two open-source systems (Xerces-J and Gantt). We used the library JHotDraw as the code base representing good design/programming practices. In both systems, we found that 90% of the riskiest classes were defects, a precision far superiour to state of the art rule-based approaches

    Model refactoring by example: A multi‐objective search based software engineering approach

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    Declarative rules are frequently used in model refactoring in order to detect refactoring opportunities and to apply the appropriate ones. However, a large number of rules is required to obtain a complete specification of refactoring opportunities. Companies usually have accumulated examples of refactorings from past maintenance experiences. Based on these observations, we consider the model refactoring problem as a multi objective problem by suggesting refactoring sequences that aim to maximize both structural and textual similarity between a given model (the model to be refactored) and a set of poorly designed models in the base of examples (models that have undergone some refactorings) and minimize the structural similarity between a given model and a set of well‐designed models in the base of examples (models that do not need any refactoring). To this end, we use the Non‐dominated Sorting Genetic Algorithm (NSGA‐II) to find a set of representative Pareto optimal solutions that present the best trade‐off between structural and textual similarities of models. The validation results, based on 8 real world models taken from open‐source projects, confirm the effectiveness of our approach, yielding refactoring recommendations with an average correctness of over 80%. In addition, our approach outperforms 5 of the state‐of‐the‐art refactoring approaches.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/143783/1/smr1916.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/143783/2/smr1916_am.pd

    A Systematic Literature Review on Software Refactoring

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    Due to the growing complexity of software systems, there has been a dramatic increase in research and industry demand on refactoring. Refactoring research nowadays addresses challenges beyond code transformation to include, but not limited to, scheduling the opportune time to carry refactoring, recommending specific refactoring activities, detecting refactoring opportunities and testing the correctness of applied refactoring. Very few studies focused on the challenges that practitioners face when refactoring software systems and what should be the current refactoring research focus from the developers’perspective and based on the current literature. Without such knowledge, tool builders invest in the wrong direction, and researchers miss many opportunities for improving the practice of refactoring. In this thesis, we collected papers from several publication sources and analyzed them to identify what do developers ask about refactoring and the relevant topics in the field We found that developers and researchers are asking about design patterns, design and user interface refactoring, web services, parallel programming, and mobile apps. We also identified what popular refactoring challenges are the most difficult and the current important topics and questions related to refactoring. Moreover, we discovered gaps between existing research on refactoring and the challenges developers face.Master of ScienceSoftware Engineering, College of Engineering & Computer ScienceUniversity of Michigan-Dearbornhttps://deepblue.lib.umich.edu/bitstream/2027.42/154827/1/Jallal Elhazzat Final Thesis.pdfDescription of Jallal Elhazzat Final Thesis.pdf : Thesi

    Imagining Moral Enhancement Practices

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    Since 2008, the so-called ‘moral enhancement debate’ asks whether we should actively pursue the development of moral enhancement technologies, and whether it would be permissible – or even obligatory – to put them to use, provided that these interventions would be effective and safe? Whereas ‘traditional methods’ of moral betterment (such as upbringing, socialization and education) are arguably as old as humanity itself, the debate on moral bioenhancement focuses on the desirability of methods based on novel biomedical insights and the use of biomedical methods. The debate follows a significant rise in fundamental research on the (neuro)biological and genetic underpinnings of morality. Potential interventions that are being discussed range from various types of psychopharmaceuticals, neurostimulation, and genetic selection and engineering. Until now, the theoretical debate on moral (bio)enhancement has a strong speculative character and mostly precedes and runs ahead of realistic scientific possibilities. Moreover, to date, the debate risks lacking focus and real world impact, as different commentators fail to agree on how to understand and define moral enhancement. This under-examination of potential practices of moral enhancement is significant because without specifying intended users, contexts of implementation, and the goals and objectives of developing and applying potential biomedical possibilities for optimizing morally relevant capacities, it is not clear who should be concerned about this debate. At the same time, existing or emerging practices that already contain elements of ‘moral enhancement’ but as yet lack ethical attention and ethical scrutiny, risk staying out of sight. In order to address this problem, this thesis focuses on (present and emerging) moral enhancement practices, in order to identify ethical issues that are not necessarily part of the current debate on moral enhancement. Rather than distinguishing in a blanket fashion desirable from undesirable moral enhancement technologies, this thesis intends to formulate conditions and ethical requirements for ethically justifiable moral enhancement practices

    Relations of family and school attachment to forms of learner violence in secondary school communities in Amathole education district, Eastern Cape

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    Adolescents in the schools in South Africa have been victims of many social problems such as violence and crime as a result of background influence. They have been both victims and perpetrators of this violence. Problems of attachment to both school and home have always been blamed for the adolescents’ deviance. South African schools are affected by this verbal and physical violence which presumably emanates from learners poor connections with school and home. The background of societies such as economic deprivation has also been presumed to have an impact on the way adolescents conduct themselves in schools. There is no research that has verified the correlation between violence and attachment to bases of attachment - home and school in South Africa, especially in the Eastern Cape Province. A survey was conducted in more than ten schools in the Amathole District where 317 learners’ opinions on their observation of cases of verbal and physical violence in their schools, and on their attachment to both home and school were collected through a 40 item questionnaire. The questionnaire had five sections (a) to (e). The first section (a) required learners to enter their biographical information; gender, age, grade, and quintile classification. The second section (b) required learners to rate their attachment to their homes and to their care givers. The third section (c) required learners to rate their connectedness to their schools. The fourth section (d) required learners to supply information on their observation and involvement in verbal violence. The final section (e) with items adopted from section (d) and customised required learners to rate their observation and involvement in physical violence. Descriptive statistics were used to glean frequencies and the overall levels of attachment and violence amongst learners. The study also looked at significant differences in attachment (both family and school) and violence (both verbal and physical) using gender and socio-economic profiles of the learners and schools (quintile system) as sorting or categorising variables. One major finding which is contrary to most theory and may be as a result of social dynamics is that statistics suggested that gender and socio-economic variables had little bearing on violence and attachment. Through the use of SPSS, the Spearman’s rho correlation coefficients were calculated to answer the sub-questions on the relationship between family and school attachment, and school violence (both verbal and physical). There were notable negative and positive correlations between school attachment and verbal violence; for example there was a positive correlation between teachers making learners hate school and learner-involvement in swearing. There was also a negative correlation between school buildings making learners proud and schools and homes being to blame for the frequency of verbal violence in the schools. There were also notable correlations between attachment to family and verbal violence such as the correlation between the frustration by parents’ lack of concern and learners’ involvement in verbal violence without any clear reason. With regard to physical violence there was a negative correlation between parents having time to discuss life with their children and the frequency of physical violence in the schools. There was however a negative correlation between one’s pride in one’s school and the blame on schools for instigating school violence. From these correlations implications for school violence prevention could be drawn. The study reveals that a lot needs to be done by the schools, parents, the government, and the community to enhance learner attachment to both school and home. However, for all the stake holders to succeed government must take the leading role in speeding up the process of reducing poverty in the communities. This is premised on the fact that some findings reveal that frequency of violence increases in an environment of frustration and anger. Schools as care-givers can also introduce many interventions such as counselling workshops to equip teachers with professional crisis management. The research may encourage the Department of Education and schools to adopt violence prevention programs implemented in countries (like United States of America’s Olweus bullying and violence prevention program) for use in bringing communities together to work against school violence. These findings might strengthen the South African Department of Education’s Safe Schools Programs

    Tawḥīdic Allah or the Trinity in View of Inherent Human Relatedness

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    This dissertation is an inquiry into the nature of the Deity in view of human relationships. Human relationships exist and are definitive of what it means to exist as a human. In this sense, human relating is an inherent aspect of the experience of humanity, i.e., they are inescapable. Does the Christian doctrine of Trinity or Islam\u27s doctrine of Tawhidic (monadic) Allah more adequately account for the existence of human relationships and their inescapability? This question is analyzed by comparing the Tawhidic nature of Allah with the Trinitarian nature of God in order to evaluate and clarify which doctrine is the best explanation for human relationships. Thus, this is an abductive argument, inferring from the evidence to the best explanation. By first reflecting on how humanity exists in terms of oneness, distinctness, and relatedness, the doctrine of Tawhidic Allah is investigated to observe how well it grounds these aspects of human relationships. Then, the same is done concerning the Trinity\u27s ability to ground these. The conclusion compares and contrasts the Trinity and Allah to explain which one better accounts for human relationships. Following this conclusion, there are a number of ramifications that are discussed

    Pandora’s Box

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    In this book, written between 1979 and 2020, Gilbert Lewis distills a lifetime of insights he garnered as a medical anthropologist. He asks: How do beliefs about illness in different societies influence their members’ ability to heal? Despite the advances of Western medicine, what can it learn from non-Western societies that consider sickness and curing to be as much a matter of social relationships as biological states? What problems arise when one set of therapeutic practices displaces another? Lewis compares Indigenous medical beliefs in New Guinea in 1968, when villagers were largely self-reliant, and in 1983, after they became dependent on Western medicine. He then widens his comparative scope by turning to West Africa and discussing a therapeutic community run by a prophet who heals the ill through confession and long-term residential care. Pandora’s Box began life with the prestigious Lewis Henry Morgan Lectures that Gilbert Lewis delivered in 1979 at the University of Rochester. He expanded them with materials gathered over the next forty years, completing the manuscript a few weeks before his death. Engagingly written, this book will inspire anthropologists, medical professionals, students, and curious readers to look with new eyes at current crises in world health
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