Software Architecture Risk Containers

Our motivation is to determine whether risks such as im- plementation error-proneness can be isolated into three types of con- tainers at design time. This paper identifies several container candidates in other research that fit the risk container concept. Two industrial case studies were used to determine which of three container types tested is most effective at isolating and predicting at design time the risk of im- plementation error-proneness. We found that Design Rule Containers were more effective than Use Case and Resource Containers

A Process to Effectively Identify “Guilty” Performance Antipatterns

Abstract. The problem of interpreting the results of software perfor-mance analysis is very critical. Software developers expect feedbacks in terms of architectural design alternatives (e.g., split a software compo-nent in two components and re-deploy one of them), whereas the results of performance analysis are either pure numbers (e.g. mean values) or functions (e.g. probability distributions). Support to the interpretation of such results that helps to fill the gap between numbers/functions and software alternatives is still lacking. Performance antipatterns can play a key role in the search of performance problems and in the formulation of their solutions. In this paper we tackle the problem of identifying, among a set of detected performance antipatterns, the ones that are the real causes of problems (i.e. the “guilty ” ones). To this goal we intro-duce a process to elaborate the performance analysis results and to score performance requirements, model entities and performance antipatterns. The cross observation of such scores allows to classify the level of guilti-ness of each antipattern. An example modeled in Palladio is provided to demonstrate the validity of our approach by comparing the performance improvements obtained after removal of differently scored antipatterns

Weighted automata as coalgebras in categories of matrices

The evolution from non-deterministic to weighted automata represents a shift from qual- itative to quantitative methods in computer science. The trend calls for a language able to reconcile quantitative reasoning with formal logic and set theory, which have for so many years supported qualitative reasoning. Such a lingua franca should be typed, poly- morphic, diagrammatic, calculational and easy to blend with conventional notation. This paper puts forward typed linear algebra as a candidate notation for such a unifying role. This notation, which emerges from regarding matrices as morphisms of suitable categories, is put at work in describing weighted automata as coalgebras in such categories. Some attention is paid to the interface between the index-free (categorial) language of matrix algebra and the corresponding index-wise, set-theoretic notation.Fundação para a Ciência e a Tecnologia (FCT

A deep phenotyping experience: up to date in management and diagnosis of Malan syndrome in a single center surveillance report

Background Malan syndrome (MALNS) is a recently described ultrarare syndrome lacking guidelines for diagnosis, management and monitoring of evolutive complications. Less than 90 patients are reported in the literature and limited clinical information are available to assure a proper health surveillance. Results A multidisciplinary team with high expertise in MALNS has been launched at the "Ospedale Pediatrico Bambino Gesu", Rome, Italy. Sixteen Italian MALNS individuals with molecular confirmed clinical diagnosis of MALNS were enrolled in the program. For all patients, 1-year surveillance in a dedicated outpatient Clinic was attained. The expert panel group enrolled 16 patients and performed a deep phenotyping analysis directed to clinically profiling the disorder and performing critical revision of previously reported individuals. Some evolutive complications were also assessed. Previously unappreciated features (e.g., high risk of bone fractures in childhood, neurological/neurovegetative symptoms, noise sensitivity and Chiari malformation type 1) requiring active surveillance were identified. A second case of neoplasm was recorded. No major cardiovascular anomalies were noticed. An accurate clinical description of 9 new MALNS cases was provided. Conclusions Deep phenotyping has provided a more accurate characterization of the main clinical features of MALNS and allows broadening the spectrum of disease. A minimal dataset of clinical evaluations and follow-up timeline has been proposed for proper management of patients affected by this ultrarare disorder

Reliability Analysis of Component-Based Systems with Multiple Failure Modes

This paper presents a novel approach to the reliability modeling and analysis of a component-based system that allows dealing with multiple failure modes and studying the error propagation among components. The proposed model permits to specify the components attitude to produce, propagate, transform or mask different failure modes. These component-level reliability specifications together with information about systems global structure allow precise estimation of reliability properties by means of analytical closed formulas, probabilistic modelchecking or simulation methods. To support the rapid identification of components that could heavily affect systems reliability, we also show how our modeling approach easily support the automated estimation of the system sensitivity to variations in the reliability properties of its components. The results of this analysis allow system designers and developers to identify critical components where it is worth spending additional improvement efforts

Lightweight Testing of Communication Networks with e-Motions

This paper illustrates the use of high-level domain specific models to specify and test some performance properties of complex systems, in particular Communication Networks, using a light-weight approach. By following a Model-Driven Engineering (MDE) approach, we show the benefits of constructing very abstract models of the systems under test, which can then be easily prototyped and analysed to explore their properties. For this purpose we use e-Motions, a language and its supporting toolkit that allows end-user modelling of real-time systems and their analysis in a graphical manner.Junta de Andalucía P07-TIC-03184Ministerio de Ciencia e Innovación TIN2008-0310

Search based software engineering: Trends, techniques and applications

© ACM, 2012. This is the author's version of the work. It is posted here by permission of ACM for your personal use. Not for redistribution. The definitive version is available from the link below.In the past five years there has been a dramatic increase in work on Search-Based Software Engineering (SBSE), an approach to Software Engineering (SE) in which Search-Based Optimization (SBO) algorithms are used to address problems in SE. SBSE has been applied to problems throughout the SE lifecycle, from requirements and project planning to maintenance and reengineering. The approach is attractive because it offers a suite of adaptive automated and semiautomated solutions in situations typified by large complex problem spaces with multiple competing and conflicting objectives. This article provides a review and classification of literature on SBSE. The work identifies research trends and relationships between the techniques applied and the applications to which they have been applied and highlights gaps in the literature and avenues for further research.EPSRC and E

Experience with model-based performance, reliability and adaptability assessment of a complex industrial architecture

In this paper, we report on our experience with the application of validated models to assess performance, reliability, and adaptability of a complex mission critical system that is being developed to dynamically monitor and control the position of an oil-drilling platform. We present real-time modeling results that show that all tasks are schedulable. We performed stochastic analysis of the distribution of task execution time as a function of the number of system interfaces. We report on the variability of task execution times for the expected system configurations. In addition, we have executed a system library for an important task inside the performance model simulator. We report on the measured algorithm convergence as a function of the number of vessel thrusters. We have also studied the system architecture adaptability by comparing the documented system architecture and the implemented source code. We report on the adaptability findings and the recommendations we were able to provide to the system’s architect. Finally, we have developed models of hardware and software reliability. We report on hardware and software reliability results based on the evaluation of the system architecture