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One of the main obstacle that prevents model checking from being widely used in industrial control systems is the complexity of building formal models out of PLC programs, especially when timing aspects need to be integrated. This paper brings an answer to this obstacle by proposing a methodology to model and verify timing aspects of PLC programs. Two approaches are proposed to allow the users to balance the trade-off between the complexity of the model, i.e. its number of states, and the set of specifications possible to be verified. A tool supporting the methodology which allows to produce models for different model checkers directly from PLC programs has been developed. Verification of timing aspects for real-life PLC programs are presented in this paper using NuSMV.

In large industrial control systems such as the ones installed at CERN, one of the main issues is the ability to verify the correct behaviour of the Programmable Logic Controller (PLC) programs. While manual and automated testing can achieve good results, some obvious problems remain unsolved such as the difficulty to check safety or liveness properties. This paper proposes a general methodology and a tool to verify PLC programs by automatically generating formal models for different model checkers out of ST code. The proposed methodology defines an automata-based formalism used as intermediate model (IM) to transform PLC programs written in ST language into different formal models for verification purposes. A tool based on Xtext has been implemented that automatically generates models for the NuSMV and UPPAAL model checkers and the BIP framework.

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.

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 inmunoglobulina. 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 España, 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. No

The UNICOS (UNified Industrial COntrol System) framework was created back in 1998. Since then a noticeable number of applications in different domains have used this framework. Furthermore UNICOS has been formalized and its supervision layer has been reused in other kinds of applications (e.g. monitoring or supervisory tasks) where a control layer is not necessarily UNICOS oriented. The process control package has been reformulated as the UNICOS CPC package (Continuous Process Control) and a reengineering process has been followed. The drive behind these noticeable changes was (1) being able to upgrade to the new more performing IT technologies in the automatic code generation, (2) being flexible enough to create new additional device types to cope with other needs (e.g. Vacuum or Cooling and Ventilation applications) without major impact on the framework or the PLC code baselines and (3) enhance the framework with new functionalities (e.g. recipes). This publication addresses the motivation, changes, new functionalities and results obtained. It introduces in an overall view the technologies used and changes followed, emphasizing what has been gained for the developer and the final user. Finally some of the new domains where UNICOS CPC has been used will be illustrated.

The Continuous Process Control package (CPC) is one of the components of the CERN Unified Industrial Control System framework (UNICOS) [1]. As a part of this framework, UNICOS-CPC provides a well defined library of device types, amethodology and a set of tools to design and implement industrial control applications. The new CPC version uses the software factory UNICOS Application Builder (UAB) [2] to develop CPC applications. The CPC component is composed of several platform oriented plugins PLCs and SCADA) describing the structure and the format of the generated code. It uses a resource package where both, the library of device types and the generated file syntax, are defined. The UAB core is the generic part of this software, it discovers and calls dynamically the different plug-ins and provides the required common services. In this paper the UNICOS CPC6 package is introduced. It is composed of several plug-ins: the Instance generator and the Logic generator for both, Siemens and Schneider PLCs, the SCADA generator (based on PVSS) and the CPC wizard as a dedicated plug-in created to provide the user a friendly GUI. A tool called UAB Bootstrap will manage the different UAB components, like CPC, and its dependencies with the resource packages. This tool guides the control system developer during the installation, update and execution of the UAB components.

The CERN Unified Industrial Control Systems framework (UNICOS) is a software generation methodology and a collection of development tools that standardizes the design of industrial control applications [1]. A Software Factory, named the UNICOS Application Builder (UAB) [2], was introduced to ease extensibility and maintenance of the framework, introducing a stable metamodel, a set of platformindependent models and platformspecific configurations against which code generation plugins and configuration generation plugins can be written. Such plugins currently target PLC programming environments (Schneider and SIEMENS PLCs) as well as SIEMENS WinCC Open Architecture SCADA (previously known as ETM PVSS) but are being expanded to cover more and more aspects of process control systems. We present what constitutes the UNICOS metamodel and the models in use, how these models can be used to capture knowledge about industrial control systems and how this knowledge can be leveraged to generate both code and configuration for a variety of target usages.

Antecedentes: La exploración ecográfica entre las semanas 11 y 14 tiene un papel fundamental en el cribado de anomalías cromosómicas, siendo la medida de la translucencia nucal un método bien establecido y ampliamente aceptado para este fin. Objetivo: Evaluar retrospectivamente la evolución de los fetos con translucencia nucal aumentada y cariotipo normal. Método: Se recogieron los datos de 104 fetos con TN >percentil 95 (p95) entre las semanas 11 y 14, evaluados en nuestro centro. En los 61 que resultaron eu-ploides, se estudió la incidencia de anomalías estructurales diagnosticadas tanto prenatalmente como tras el nacimiento, así como las pérdidas fetales anteparto. De estos fetos, nacieron sanos el 80% cuando la TN estaba entre p95 y 3,4 mm, el 50% con TN entre 3,5 y 4,4 mm, el 30% con TN entre 4,5 y 5,4 mm, y el 18% con TN > 5,5 mm. Entre los 4 recién nacidos euploides con patología, hubo 3 con cardiopatía. Conclusión: La presencia de TN aumentada entre las 11 -14 semanas en fetos euploides se asocia a un incremento del riesgo de anomalías estructurales mayores, principalmente cardiacas. La prevalencia de malformaciones aumenta significativamente con TN >3,5 mm, y el pronóstico gestacional adverso empeora conforme aumenta la medida de la TN. Background: Ultrasound scan has a main role at the 11-14 weeks screening for chromosomal abnormalities. The measurement of nuchal translucency (NT) thickness is a widespread stablished method to achieve this target. Objective: To assess retrospectively the outcome of fetuses with increased nuchal translucency and normal karyotype. Method: Data were collected from 104 fetuses with NT > 95th percentile at 11 to 14 weeks of gestation, followed in our institution. The sixty one euploid fetuses were studied in order to determine the incidence of structural abnormalities, diagnosed either before or after delivery, as well as antenatal fetal loss. Among these fetuses, there were no malformations at birth in 80% for NT between the 95th percentile and 3.4 mm; 50% for NT between 3.5 and 4.4 mm; 30% for NT of 4.5-5.4 mm; and 18% for NT > 5.5 mm. There were 4 euploid newborns with some kind of structural defect at birth, 3 of them presented a cardiac malformation. Conclusion: The presence of increased NT at 11-14 weeks scan in euploid fetuses it's associated with a higher risk of major structural abnormalities, mainly cardiac ones. The prevalence of malformations is significantly increased for NT > 3.5 mm, and the adverse perinatal outcome is directly associated with the thickness of NT.