A model for requirements traceability in an heterogeneous model-based design process. Application to automotive embedded systems

Requirements traceability modeling is a key issue in real-time embedded design process. In such systems, requirements are of different nature (software-related, system-related, functional and non functional) and must be traced through a multi level design flow which integrates multiple and heterogeneous models. Validation and Verification (V&V) activities must be performed on models and on the final product to check if they are matching the initial require-ments. Results of a design and of V&V activities must impact the traceability information. We propose the DARWIN4REQ metamodel for requirement traceability based on three indepen-dent flows (requirement model, solution model and V&V model). The DARWIN4REQ metamodel establishes the link between these flows and allows a full traceability of requirements including the heterogeneous models. This paper presents the DARWIN4REQ metamodel and its use in the context of heterogeneous models for requirement modeling, design and V&V. An automotive application illustrates the approach with SYSML, EAST_ADL2 and MARTE for the design and SIMULINK, SyNDEx and TIMESQUARE for V&V activities

Non-functional property analysis using UML2.0 and model transformations

Real-time embedded architectures consist of software and hardware parts. Meeting non-functional constraints (e.g., real-time constraints) greatly depends on the mappings from the system functionalities to software and hardware components. Thus, there is a strong demand for precise architecture and allocation modeling, amenable to performance analysis. The report proposes a model-driven approach for the assessment of the quality of allocations of the system functionalities to the architecture. We consider two technical domains: the UML domain for the definition of the model elements (for both description and analysis), and an analysis domain, external to UML, used for formal verification. This report defines three meta-models, one for each domain, and provides automated transformations within and between these domains. A special attention is then paid to temporal property analysis, based on a particular analysis model: the Modular and Hierarchical Time Petri Nets

Scheduling Multi Clock Real Time Systems: From Requirements to Implementation

NewPort BeachInternational audienceThis paper presents an approach for modeling simulating and analyzing multi clocks real time systems during the different steps of a design. These steps range from the first requirements to a model allocated on a specific execution platform. The \uml \marte profile and the \ccsl language are used together to specify the causal and temporal characteristics of the software as well as the hardware parts of the system. The \tsq environment allows a simulation of such specification and the detection of potential errors and deadlocks. When the specification refinement is finished, to prove the specification correctness, the \ccsl specification is used to generate a synchronous model and some observers in Esterel. We illustrate the approach through a spark ignition control system

Non-functional property analysis using UML2.0 and model transformations

Real-time embedded architectures consist of software and hardware parts. Meeting non-functional constraints (e.g., real-time constraints) greatly depends on the mappings from the system functionalities to software and hardware components. Thus, there is a strong demand for precise architecture and allocation modeling, amenable to performance analysis. The report proposes a model-driven approach for the assessment of the quality of allocations of the system functionalities to the architecture. We consider two technical domains: the UML domain for the definition of the model elements (for both description and analysis), and an analysis domain, external to UML, used for formal verification. This report defines three meta-models, one for each domain, and provides automated transformations within and between these domains. A special attention is then paid to temporal property analysis, based on a particular analysis model: the Modular and Hierarchical Time Petri Nets

Marte CCSL and East-ADL2 Timing Requirements

Short version published to ISORC 2009, Tokyo, Japan, IEEE http://dx.doi.org/10.1109/ISORC.2009.18In the automotive domain, several loosely-coupled Architecture Description Languages (ADLs) compete to provide a set of abstract modeling and analysis services on top of the implementation code. In an effort to make all these languages, and more importantly their underlying models, interoperable, we use the UML Profile for MARTE as a pivot to define the semantics of these models. In this paper, we particularly focus on East-ADL2. We discuss the benefits of having an integrated, MARTE-centered, approach. We give a formal semantics of East-ADL2 timing requirements. Relying on this semantics, several kinds of analysis become possible. Requirements become executable and simulations are run. A constraint solver is used to detect logical inconsistencies. Our proposal is illustrated on an Anti-lock Braking System (ABS)

Multiform Time in UML for Real-time Embedded Applications

The original publication is available at ieee.org (http://dx.doi.org/10.1109/RTCSA.2007.51)International audienceEach domain has its own interpretation of time. We propose to extend UML, which is more and more used in the domain of real-time embedded applications, with a concept of time inherited from reactive system modeling : multiform time. After a brief review of some UML profiles, we present our extensions and we illustrate on an example from the automotive industry how to represent and to constraint behaviors depending on multiform time. We advocate that this model of time offers wider possibilities than restricting models only to the physical time

A multiform time approach to real-time system modeling: Application to an automotive system

The original publication is available at ieee.org ({http://dx.doi.org/10.1109/SIES.2007.4297340)International audienceIn the context of an effort to answer the OMG RFP for Modeling and Analysis of Real-Time Embedded systems (MARTE), we are defining extensions to the simple time model of UML2. After a brief review of some time-related UML profiles, we focus on the specificity of our approach: the ability to take account of multiform time-a concept inherited from reactive system modeling. Using an example from the automotive industry, we illustrate the use of our profile to represent, to constraint and to analyze behaviors depending on multiform time

Marte CCSL to execute East-ADL Timing Requirements

Extended version available as a research report RR-6781International audienceIn the automotive domain, several loosely-coupled Architecture Description Languages (ADLs) compete to provide a set of abstract modeling and analysis services on top of the implementation code. In an effort to make all these languages, and more importantly their underlying models, interoperable, we use the UML Profile for MARTE as a pivot to define the semantics of these models. In this paper, we particularly focus on East-ADL2. We discuss the benefits of having an integrated, MARTE-centered, approach. We give a formal semantics of East-ADL2 timing requirements. Relying on this semantics, several kinds of analysis are possible. Requirements become executable and simulations are run. A constraint solver is used to detect logical inconsistencies. Our proposal is illustrated on an Anti-lock Braking System (ABS)

Receptor binding and degradation of urokinase-type plasminogen activator by human mesangial cells

Receptor binding and degradation of urokinase-type plasminogen activator by human mesangial cells. The binding of [125I] labeled urokinase-type plasminogen activator (u-PA) was studied on human mesangial cells (MC) in culture. The binding of active [125I]u-PA at 37°C reached a plateau after 30 minutes of incubation and remained stable for at least four hours. When the supernatant was analyzed with trichloracetic acid (TCA), TCA soluble radioactive material could be detected after a lag phase of 30 minutes, and then increased linearly for four hours. Analysis by electrophoresis on SDS PAGE and autoradiography of the cell associated radioactivity and of the intracellular content showed that active u-PA and u-PA complexed to plasminogen activator inhibitor type-1 (PAI-1) were bound to the cell surface, but only u-PA/PAI-1 complexes were internalized and degraded. Therefore, the Kd and the number of binding sites were determined by competitive inhibition curves at 4°C using diisopropyl-fluorophosphate (DFP) u-PA. Scatchard plots showed a Kd = 400 ± 30 pM, and Bmax = 240,000 ± 25,000 sites/cell. Excess of the amino terminal fragment of u-PA (ATF) completely blocked the specific binding of [125I]u-PA, confirming that the binding of u-PA was independent of the presence of the active site and/or of the formation of complexes with PAI-1. 3H thymidine incorporation by mesangial cells after stimulation with 100nM active u-PA showed that u-PA had a moderate but significant mitogenic effect, in contrast to inactive u-PA and ATF. However, this mitogenic effect was not accompanied by a proliferative effect. Pretreatment of mesangial cell with a phosphoinositol-specific phospholipase C decreased the binding of [125I]u-PA by 60%, indicating that the majority of the u-PA receptor is anchored in the membrane by a phosphatidylinositol group. These results, together with a positive labeling of MC with monoclonal antibodies to the receptor of U937 cells, and the positive RNA hybridization with the cDNA probe for the human receptor cloned from U937 cells, indicate that the u-PA receptor on mesangial cells is identical to the one of U937 cells. In conclusion, human mesangial cells in culture express a specific receptor for u-PA, which could play a major role in the regulation of u-PA activity by degrading u-PA complexed to PAI-1

Stable cell line of T-SV40 immortalized human glomerular visceral epithelial cells

Stable cell line of T-SV40 immortalized human glomerular visceral epithelial cells. Human subcultures (third passage) of glomerular visceral epithelial cells (VEC) isolated from one month old kidney were successfully transfected by two recombinant plasmids containing the cloned oncogenes from the simian virus 40 large T antigen and H-ras gene. One postcrisis cell clone (56/10 A1) was selected, propagated and characterized. One hundred percent of the 56/10 A1 cells (current passage > 100th; doubling time 30 hrs) expressed the nuclear T-SV40 antigen assayed by IF; the cells failed to express H-ras (RNA blot analysis). Immortalized cells were morphologically and phenotypically compared to parental cell type (third passage). Phenotypic characterization of the 56/10 Al cells was achieved using indirect immunofluorescence (IF) and immunogold silver staining coupled to bright field and epipolarization microscopy. Both parental and 56/10 A1 cells displayed positivity for cytokeratin, CALLA and PHM5, whereas von Willebrand factor was not detected in the two cell types. Since we have previously shown that human glomerular epithelial cells in culture synthetize plasminogen activator (PA) related compounds, we investigated the secretion pattern of these products in parental and transfected cells. Zymographic analysis of secreted PA related compounds revealed production of free urokinase (u-PA) and type 1 plasminogen activator inhibitor (PAI-1) complexed to tissular plasminogen activator (t-PA). Finally, in the transfected cells, increased cGMP generation under atrial natriuretic factor (ANF) stimulation agreed with previous work performed on nontransfected human VEC. In conclusion, the establishment of a human permanent cell line which retains most of the phenotypic features of parental glomerular visceral epithelial cells should represent a new tool to study human glomerular cell functions