Model Checking a C++ Software Framework, a Case Study

This paper presents a case study on applying two model checkers, SPIN and DIVINE, to verify key properties of a C++ software framework, known as ADAPRO, originally developed at CERN. SPIN was used for verifying properties on the design level. DIVINE was used for verifying simple test applications that interacted with the implementation. Both model checkers were found to have their own respective sets of pros and cons, but the overall experience was positive. Because both model checkers were used in a complementary manner, they provided valuable new insights into the framework, which would arguably have been hard to gain by traditional testing and analysis tools only. Translating the C++ source code into the modeling language of the SPIN model checker helped to find flaws in the original design. With DIVINE, defects were found in parts of the code base that had already been subject to hundreds of hours of unit tests, integration tests, and acceptance tests. Most importantly, model checking was found to be easy to integrate into the workflow of the software project and bring added value, not only as verification, but also validation methodology. Therefore, using model checking for developing library-level code seems realistic and worth the effort.Comment: In Proceedings of the 27th ACM Joint European Software Engineering Conference and Symposium on the Foundations of Software Engineering (ESEC/FSE '19), August 26-30, 2019, Tallinn, Estonia. ACM, New York, NY, USA, 11 page

Human case of swine influenza A (H1N1), Aragon, Spain, November 2008

A human case of swine influenza A (H1N1) in a 50-year-old woman from a village near Teruel (Aragon, in the north-east of Spain), with a population of about 200 inhabitants, has been reported in November 2008.S

Construcción de un índice de privación por zona básica de salud en Aragón a partir de datos de censo de 2011

Fundamentos: La medición de las desigualdades mediante indicadores compuestos facilita la priorización y puesta en marcha de acciones de salud pública. La fuente de información más comúnmente utilizada para ello ha sido el Censo de Población y viviendas de 2011 (CPV_2011). El objetivo fue validar la utilización del CPV_2011 por Zona de Salud (ZBS) y construir un índice de privación (IP) por ZBS así como analizar su asociación con la mortalidad en Aragón. Métodos: Estudio ecológico por ZBS. El CPV_2011, con diseño muestral, se validó mediante un test de homogeneidad de Chi_cuadrado y se calcularon 26 indicadores socioeconómicos. Se obtuvo el coeficiente de correlación de Spearman entre indicadores socioeconómicos y Razones de Mortalidad Estandarizadas (REM). Se realizó un análisis de componentes principales (ACP) con los indicadores correlacionados significativamente, extrayendo los componentes con autovalores mayores a 1 y se obtuvo la matriz rotada (Varimax). Se realizaron ACP con las variables de cada componente extrayendo un único factor. Se agruparon las ZBS en cuartiles, según el factor calculando tasas de mortalidad ajustadas a población estándar europea por edad, sexo y cuartil. El factor que más discrimina por cuartiles se consideró IP y se recalculó para ZBS urbanas con idénticas variables. Resultados: La validación de la muestra del CPV_2011, detectó cuatro ZBS infrarrepresentadas. 17 indicadores socioeconómicos se correlacionaron con REM. Del primer ACP se extrajeron 3 componentes, eligiendo como IP, el formado por %Desempleo, %Asalariados eventuales, %Instrucción Insuficiente 16-64 años y %Extranjeros. Las varianzas explicadas fueron 59,7% y 73,8% en el IP urbano. En hombres, la mortalidad en el cuartil menos privado (544,7 por 105; IC95%:515,8-573,6), fue inferior a la del más privado (618,7 por 105; IC95%:589,4,648,0). Conclusiones: El IP permite identificar ZBS desfavorecidas constituyendo una herramienta para evidenciar desigualdades y planificar intervenciones según necesidades. Background: The measurement of inequalities using composite indicators facilitates the prioritization and implementation of public health actions. The most commonly source of information used for this has been the Population and Housing Census of 2011 (PCH_2011). The objective of this study was to evaluate the use of PHC_2011 and develop a deprivation index (DI) by Basic Healthcare Area (BHA) and to analyse its association with mortality in Aragon. Methods: Ecological study by BHA. Since PHC_2011 was a sample of the population it was validated by the Chi-square test for homogeneity. 26 socioeconomic indicators were calculated. Spearman correlation coefficients were used to evaluate the relationship between socioeconomic indicators and Standardized Mortality Ratios (SMR). Principal Component Analyses (PCA) were conducted using the indicators in which a significant correlation was found. Components with eigenvalues higher than 1 were extracted, and the rotated matrix (Varimax) was obtained. PCA from each component were conducted, extracting only one factor. BHA were grouped into, according to the deprivation index values. Mortality rates adjusted to the European Standard Population by age, sex and quartile were calculated. The most discriminant factor by quartiles was considered DI. A different DI for urban areas was obtained from the same variables. Results: The validation of PHC sample detected 4 underrepresented BHA. 17 socioeconomic indicators were significatively correlated with SMR. From the first PCA, 3 components were obtained. The DI included % unemployment, % eventual workers, % insufficient education 16-64 years old and % foreigners. The % of variance explained by the DI was 59.7% and 73.8% in urban areas. In men, mortality in the quartile with the lowest deprivation (544, 7 per 105; CI95%: 515, 8-573, 6) was significatively lower than in the most deprivated areas(618, 7 per 105; CI95%: 589, 4-648, 0). Conclusions: This new DI allows us to identify deprived BHA. This is a useful tool to bring to light health inequalities and to plan interventions according to population's needs

A Configurable CEGAR Framework with Interpolation-Based Refinements

International audienceCorrectness of software components in a distributed system is a key issue to ensure overall reliability. Formal verification techniques such as model checking can show design flaws at early stages of development. Abstraction is a key technique for reducing complexity by hiding information, which is not relevant for verification. Counterexample-Guided Abstraction Refinement (CEGAR) is a verification algorithm that starts from a coarse abstraction and refines it iteratively until the proper precision is obtained. Many abstraction types and refinement strategies exist for systems with different characteristics. In this paper we show how these algorithms can be combined into a configurable CEGAR framework. In our framework we also present a new CEGAR configuration based on a combination of abstractions, being able to perform better for certain models. We demonstrate the use of the framework by comparing several configurations of the algorithms on various problems, identifying their advantages and shortcomings

Caso de Rabia canina importada de Marruecos a España. Junio de 2013.

El 5 de junio de 2013, el servicio de epidemiología de Castilla-La Mancha notificó al Centro de Coordinación de Alertas y Emergencias Sanitarias (CCAES) un caso confirmado de rabia en un perro abatido por la policía en la ciudad de Toledo el 1 de junio. El animal había mordido a cuatro niños y un adulto. Uno de los niños requirió hospitalización e ingresó en la Unidad de Cuidados Intensivos. El Laboratorio Nacional de Referencia para lyssavirus realizó el diagnóstico por inmunofluorescencia, PCR y cultivo celular, así como la secuenciación genómica de la cepa del virus y su comparación con las cepas circulantes en países endémicos. Inmediatamente tras conocerse los resultados, los cuatro niños y el adulto recibieron profilaxis post-exposición con vacuna e inmunoglobulina1 . Las investigaciones preliminares revelaron que el perro había viajado con sus dueños el 22 de mayo desde Cataluña a una pequeña localidad a 10 km de Toledo. Según los dueños, el perro había escapado unos días antes de ser localizado en Toledo. En ese momento existía la sospecha, aún sin confirmar, de que el perro hubiera estado unos meses antes en Marruecos. España (territorio peninsular, Islas Baleares y Canarias) ha estado libre de rabia terrestre desde 1978. Tras recibir la notificación y según lo establecido en el Plan de Contingencia para el control de la rabia en España2 , se constituyó una comisión técnica formada por representantes de la Dirección General de Salud Pública, Calidad e Innovación del Ministerio de Sanidad, Servicios Sociales e Igualdad (DGSPCI), la Dirección General de Sanidad de la Producción Agrícola y Ganadera del Ministerio de Agricultura, Alimentación y Medio Ambiente (DGSPA), las Comunidades Autónomas afectadas, el Laboratorio Nacional de Referencia de rabia y el Centro Nacional de Epidemiología (CNE). Los objetivos de esta comisión eran coordinar la investigación del suceso, evaluar el riesgo para la salud humana y animal, proponer la activación de los correspondientes niveles de alerta y coordinar la aplicación de las medidas de control apropiadas.N

Transforming PLC Programs into Formal Models for Verification Purposes

Most of CERN’s industrial installations rely on PLC-based (Programmable Logic Controller) control systems developed using the UNICOS framework. This framework contains common, reusable program modules and their correctness is a high priority. Testing is already applied to find errors, but this method has limitations. In this work an approach is proposed to transform automatically PLC programs into formal models, with the goal of applying formal verification to ensure their correctness. We target model checking which is a precise, mathematical-based method to check formalized requirements automatically against the system

Testing and Verification of PLC Code for Process Control

Functional testing of PLC programs has been historically a challenging task for control systems engineers