42 research outputs found

    Automatic generation of UML profile graphical editors for Papyrus

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    UML profiles offer an intuitive way for developers to build domain-specific modelling languages by reusing and extending UML concepts. Eclipse Papyrus is a powerful open-source UML modelling tool which supports UML profiling. However, with power comes complexity, implementing non-trivial UML profiles and their supporting editors in Papyrus typically requires the developers to handcraft and maintain a number of interconnected models through a loosely guided, labour-intensive and error-prone process. We demonstrate how metamodel annotations and model transformation techniques can help manage the complexity of Papyrus in the creation of UML profiles and their supporting editors. We present Jorvik, an open-source tool that implements the proposed approach. We illustrate its functionality with examples, and we evaluate our approach by comparing it against manual UML profile specification and editor implementation using a non-trivial enterprise modelling language (Archimate) as a case study. We also perform a user study in which developers are asked to produce identical editors using both Papyrus and Jorvik demonstrating the substantial productivity and maintainability benefits that Jorvik delivers

    Learning to Learn in Collective Adaptive Systems: Mining Design Patterns for Data-driven Reasoning

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    Engineering collective adaptive systems (CAS) with learning capabilities is a challenging task due to their multidimensional and complex design space. Data-driven approaches for CAS design could introduce new insights enabling system engineers to manage the CAS complexity more cost-effectively at the design-phase. This paper introduces a systematic approach to reason about design choices and patterns of learning-based CAS. Using data from a systematic literature review, reasoning is performed with a novel application of data-driven methodologies such as clustering, multiple correspondence analysis and decision trees. The reasoning based on past experience as well as supporting novel and innovative design choices are demonstrated

    Genetic Improvement @ ICSE 2020

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    Following Prof. Mark Harman of Facebook's keynote and formal presentations (which are recorded in the proceedings) there was a wide ranging discussion at the eighth international Genetic Improvement workshop, GI-2020 @ ICSE (held as part of the 42nd ACM/IEEE International Conference on Software Engineering on Friday 3rd July 2020). Topics included industry take up, human factors, explainabiloity (explainability, justifyability, exploitability) and GI benchmarks. We also contrast various recent online approaches (e.g. SBST 2020) to holding virtual computer science conferences and workshops via the WWW on the Internet without face-2-face interaction. Finally we speculate on how the Coronavirus Covid-19 Pandemic will affect research next year and into the future

    Interval Change-Point Detection for Runtime Probabilistic Model Checking

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    Recent probabilistic model checking techniques can verify reliability and performance properties of software systems affected by parametric uncertainty. This involves modelling the system behaviour using interval Markov chains, i.e., Markov models with transition probabilities or rates specified as intervals. These intervals can be updated continually using Bayesian estimators with imprecise priors, enabling the verification of the system properties of interest at runtime. However, Bayesian estimators are slow to react to sudden changes in the actual value of the estimated parameters, yielding inaccurate intervals and leading to poor verification results after such changes. To address this limitation, we introduce an efficient interval change-point detection method, and we integrate it with a state-of-the-art Bayesian estimator with imprecise priors. Our experimental results show that the resulting end-to-end Bayesian approach to change-point detection and estimation of interval Markov chain parameters handles effectively a wide range of sudden changes in parameter values, and supports runtime probabilistic model checking under parametric uncertainty

    JAK2 V617F hematopoietic clones are present several years prior to MPN diagnosis and follow different expansion kinetics.

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    TO THE EDITOR: The JAK2 V617F mutation is the most common somatic mutation in the classical myeloproliferative neoplasms (MPNs), present in >95% of cases of polycythemia vera (PV) and ∼50% of essential thrombocythemia (ET) and myelofibrosis (MF).1⇓⇓-4 It is usually the sole identifiable driver mutation in MPNs5 and was recently also identified as a driver of age-related clonal hemopoiesis in healthy individuals.6⇓⇓-9 In order to investigate the preclinical clonal evolution of MPNs, we identified 12 individuals with a JAK2 V617F mutant MPN, who 4.6 to 15.2 years previously (median 10.2 years) had also donated blood to register with the Cyprus Bone Marrow Donor Registry at the Karaiskakio FoundationThis work was supported by the Wellcome Trust Sanger Institute (WT098051). T. McKerrell is funded by a Wellcome Trust Clinician Scientist Fellowship (100678/Z/12/Z). G.S.V. is funded by a Wellcome Trust Senior Fellowship in Clinical Science (WT095663MA), and work in his laboratory is also funded by Cancer Research UK, Bloodwise, the Kay Kendall Leukaemia Fund, and Celgene. I.V. is supported by the Spanish Ministerio de Economía y Competitividad, Programa Ramón y Cajal

    PET and SPECT Imaging in Hyperkinetic Movement Disorders

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    Movement disorders can be classified in hypokinetic (e.g., Parkinson's disease, PD) and hyperkinetic disorders (e.g., dystonia, chorea, tremor, tics, myoclonus, and restless legs syndrome). In this chapter, we will discuss results from positron emission tomography (PET) and single photon emission computed tomography (SPECT) imaging studies in patients with tremor, tics, myoclonus, and restless legs syndrome. Most studies in patients with tremor included patients with essential tremor (ET): a bilateral, largely symmetric, postural or kinetic tremor mainly involving the upper limbs and sometimes the head. Other studies evaluated patients with orthostatic tremor (OT): an unusually high frequent tremor in the legs that mainly occurs when patients are standing still. Increased regional cerebral blood flow (rCBF) and increased glucose metabolism have been found in the cerebellum, sensorimotor cortex, and thalamus in both patients with ET and OT compared to controls. Both PET and SPECT studies have evaluated the dopamine system in patients with ET and OT. Most imaging studies in patients with ET showed no, or only subtle loss of striatal tracer binding to the dopamine transporter indicating that ET is not characterized by nigrostriatal cell loss. The serotonin and/or gamma-aminobutyric acid (GABA) systems may play a role in the pathophysiology of ET. PET and SPECT imaging of the dopamine and serotonin system in patients with OT showed no abnormalities. Tics, the clinical hallmark of Gilles de la Tourette syndrome (TS), are relatively brief and intermittent involuntary movements (motor tic) and sounds (phonic tic). The essential features of tics are that (1) they can be temporarily suppressed; after suppression a rebound usually occurs with a flurry of tics; (2) the patient experiences an urge to tic, and (3) the tic is followed by a short moment of relief. Using 18F-FDG PET, it was shown that TS is a network disorder where multiple brain areas are active or inactive at the same time. The exact composition of this network is yet to be determined. Using rCBF PET and SPECT many brain regions were found to be abnormal, however, tics mostly correlated with hypoperfusion of the caudate nucleus and cingulate cortex. Both dopamine and serotonin are likely to play a role in the pathophysiology of TS. It is hypothesized that TS is characterized by low serotonin levels that modulate increased phasic dopamine release. Myoclonus is defined as a brief muscle jerk and occurs in many neurologic and non-neurologic disorders. Imaging with PET and SPECT in patients with myoclonus mainly showed abnormalities consistent with the underlying disorder. We described PET and SPECT imaging results in patients in which myoclonus was a prominent symptom. Hypoperfusion and/or hypometabolism of the frontoparietal cortex was found in patients with negative epileptic myoclonus, Alzheimer's disease, corticobasal degeneration, Creutzfeldt-Jakob disease, fatal familiar insomnia, and posthypoxic myoclonus. Other findings that were frequently reported were decreased rCBF and/or glucose metabolism in the cerebellum and thalamus and abnormalities in the dopamine system. Restless legs syndrome (RLS) is defined as an urge to move the legs accompanied with an unpleasant sensation in the legs or in another body part that is especially present during the evening and night and that can be accompanied by periodic limb movements in sleep (PLMS). Imaging studies in these patients have mainly focused on the dopamine system. Most PET studies found decreased tracer binding to the dopamine transporter, although this was not found in SPECT studies. Both PET and SPECT studies showed conflicting results regarding dopamine D2/3 receptor binding: both increased and decreased tracer binding was reported. Furthermore, it is likely that the serotonin and opioid systems also play a role in the pathophysiology of RLS.</p

    Urban renaissance in Palaio Faliro

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