503 research outputs found
Executing AADL models with UML/Marte
International audienceAADL and MARTE are two modeling formalisms supporting the analysis of real-time embedded systems. Since both cover similar aspects, a clear assessment of their respective strength and weakness is required. Building on previous works, we focus here on the time aspects of the two specifications. Relying on the MARTE Time Model and the operational semantics of its companion language CCSL we attempt to equipped UML activities with the execution semantics of an AADL specification. This is part of a much broader effort to build a generic simulator for UML models with the semantics explicitly defined within the model
Semantic Multi-View model for Low-Power
5 pagesNational audiencePower is an important concern in embedded systems. Reduction of power consumption is achieved by balancing the control of multiple domains: switching power, reducing or increasing voltage and changing the frequency on system sections. Model-Driven Engineering gives tools to model the interactions of these domains. In this work, we propose to use MARTE combined to UPF concepts to capture the structure and behavior of these multiple domains. We adopt CCSL to unify the multiform aspects among domains and to verify their proper interaction. We provide an example to illustrate MARTE representation and a simulation of multi-domain power design, specified on CCSL and running on TIMESQUARE
Multi-View Power Modeling based on UML MARTE and SysML
The development of SoC involves different activities, usually driven by specialists. These specialists use specific languages and tools to manipulate their specific concepts. The problem is that the multiple views of the system are split into different tools with redundant information. It makes it difficult to ensure consistency as well as to change from one tool to another. We propose a multi-view model where each view represents the specialist concepts in a tool-agnostic manner. The model can be kept consistent by using explicit associations instead of redundancy and tool transformation can be performed to analysis-specific tools. The approach is based on UML and two of its extensions: MARTE and SysML. It is illustrated by adding specific views to specify power management techniques. The resulting model is then transformed into a tool-specific model; \ie a model for Docea Aceplorer, a power analysis tool
A Tool-Supported Approach for Concurrent Execution of Heterogeneous Models
International audienceIn the software and systems modeling community, research on domain-specific modeling languages (DSMLs) is focused on providing technologies for developing languages and tools that allow domain experts to develop system solutions efficiently. Unfortunately, the current lack of support for explicitly relating concepts expressed in different DSMLs makes it very difficult for software and system engineers to reason about information spread across models describing different system aspects [4]. As a particular challenge, we investigate in this paper relationships between, possibly heterogeneous, behavioral models to support their concurrent execution. This is achieved by following a modular executable metamodeling approach for behavioral semantics understanding, reuse, variability and composability [5]. This approach supports an explicit model of concurrency (MoCC) [6] and domain-specific actions (DSA) [10] with a well-defined protocol between them (incl., mapping, feedback and callback) reified through explicit domain-specific events (DSE) [12]. The protocol is then used to infer a relevant behavioral language interface for specifying coordination patterns to be applied on conforming executable models [17]. All the tooling of the approach is gathered in the GEMOC studio, and outlined in the next section. Currently, the approach is experienced on a systems engineering language provided by Thales, named Capella 7. The goal and current state of the case study are exposed in this paper. 7 Cf. https://www.polarsys.org/capella
Modeling Dual Pathways for the Metazoan Spindle Assembly Checkpoint
Using computational modelling, we investigate mechanisms of signal
transduction focusing on the spindle assembly checkpoint where a single
unattached kinetochore is able to signal to prevent cell cycle progression.
This inhibitory signal switches off rapidly once spindle microtubules have
attached to all kinetochores. This requirement tightly constrains the possible
mechanisms. Here we investigate two possible mechanisms for spindle checkpoint
operation in metazoan cells, both supported by recent experiments. The first
involves the free diffusion and sequestration of cell-cycle regulators. This
mechanism is severely constrained both by experimental fluorescence recovery
data and also by the large volumes involved in open mitosis in metazoan cells.
Using a simple mathematical analysis and computer simulation, we find that this
mechanism can generate the inhibition found in experiment but likely requires a
two stage signal amplification cascade. The second mechanism involves spatial
gradients of a short-lived inhibitory signal that propagates first by diffusion
but then primarily via active transport along spindle microtubules. We propose
that both mechanisms may be operative in the metazoan spindle assembly
checkpoint, with either able to trigger anaphase onset even without support
from the other pathway.Comment: 9 pages, 2 figure
Coping with Semantic Variation Points in Domain-Specific Modeling Languages
International audienceEven if they exhibit differences, many Domain-Specific Modeling Languages (DSMLs) share elements from their concepts, notations and semantics. StateCharts is a well known family of DSMLs that share many concepts but exhibit notational differences and many execution semantics variants (called Semantic Variation Points – SVPs –). For instance, when two conflicting transitions in a state machine are enabled by the same event occurrence, which transition is fired depends on the language variant (Harel original StateCharts, UML, Rhapsody, etc.) supported by the execution tool. Tools usually provide only one implementation of SVPs. It complicates communication both between tools and end-users, and hinders the co-existence of multiple variants. More generally, Language Workbenches dedicated to the specification and implementation of eXecutable Domain-Specific Modeling Languages (xDSMLs) often do not offer the tools and facilities to manage these SVPs, making it a time-consuming and troublesome activity. In this paper, we describe a modularized approach to the operational execution semantics of xDSMLs and show how it allows us to manage SVPs. We illustrate this proposal on StateCharts
Software Development Support for Shared Sensing Infrastructures: A Generative and Dynamic Approach
International audienceSensors networks are the backbone of large sensing infras-tructures such as Smart Cities or Smart Buildings. Classical approaches suffer from several limitations hampering developers' work (e.g., lack of sensor sharing, lack of dynamicity in data collection policies, need to dig inside big data sets, absence of reuse between implementation platforms). This paper presents a tooled approach that tackles these issues. It couples (i) an abstract model of developers' requirements in a given infrastructure to (ii) timed automata and code generation techniques, to support the efficient deployment of reusable data collection policies on different infrastructures. The approach has been validated on several real-world scenarios and is currently experimented on an academic campus
EP-1349: Long term results of a phase I-II study of moderate hypofractionated IGRT in prostate cancer
Pregnant women diagnosed with gestational diabetes mellitus subjected to diet (GDMd) that do not reach normal glycaemia are passed to insulin therapy (GDMi). GDMd associates with increased human cationic amino acid transporter 1 (hCAT-1)-mediated transport of L-arginine and nitric oxide synthase (NOS) activity in foetoplacental vasculature, a phenomenon reversed by exogenous insulin. Whether insulin therapy results in reversal of the GDMd effect on the foetoplacental vasculature is unknown. We assayed whether insulin therapy normalizes GDMd-associated foetoplacental endothelial dysfunction. Primary cultures of human umbilical vein endothelial cells (HUVECs) from GDMi pregnancies were used to assay L-arginine transport kinetics, NOS activity, p44/42mapk and protein kinase B/Akt activation, and umbilical vein rings reactivity. HUVECs from GDMi or GDMd show increased hCAT-1 expression and maximal transport capacity, NOS activity, and eNOS, and p44/42mapk, but not Akt activator phosphorylation. Dilation in response to insulin or calcitonin-gene related peptide was impaired in umbilical vein rings from GDMi and GDMd pregnancies. Incubation of HUVECs in vitro with insulin (1 nmol/L) restored hCAT-1 and eNOS expression and activity, and eNOS and p44/42mapk activator phosphorylation. Thus, maternal insulin therapy does not seem to reverse GDMd-associated alterations in human foetoplacental vasculature.Fondo Nacional de Desarrollo Científico y Tecnológico Chileno 1150377 , 1150344 , 11150083Servicio de Salud de Medicina Oriente de Chile 1938–2016Marie Curie International Research 295185 - EULAMDIM
Early timing analysis based on scenario requirements and platform models
Distributed, software-intensive systems (e.g., in the automotive sector) must fulfill communication requirements under hard real-time constraints. The requirements have to be documented and validated carefully using a systematic requirements engineering (RE) approach, for example, by applying scenario-based requirements notations. The resources of the execution platforms and their properties (e.g., CPU frequency or bus throughput) induce effects on the timing behavior, which may lead to violations of the real-time requirements. Nowadays, the platform properties and their induced timing effects are verified against the real-time requirements by means of timing analysis techniques mostly implemented in commercial-off-the-shelf tools. However, such timing analyses are conducted in late development phases since they rely on artifacts produced during these phases (e.g., the platform-specific code). In order to enable early timing analyses already during RE, we extend a scenario-based requirements notation with allocation means to platform models and define operational semantics for the purpose of simulation-based, platform-aware timing analyses. We illustrate and evaluate the approach with an automotive software-intensive system
A generic framework for representing and analyzing model concurrency
Recent results in language engineering simplify the development of tool-supported executable domain-specific modeling languages (xDSMLs), including editing (e.g., completion and error checking) and execution analysis tools (e.g., debugging, monitoring and live modeling). However, such frameworks are currently limited to sequential execution traces and cannot handle execution traces resulting from an execution semantics with a concurrency model supporting parallelism or interleaving. This prevents the development of concurrency analysis tools, like debuggers supporting the exploration of model executions resulting from different interleavings. In this paper, we present a generic framework to integrate execution semantics with either implicit or explicit concurrency models, to explore the possible execution traces of conforming models, and to define strategies for helping in the exploration of the possible executions. This framework is complemented with a protocol to interact with the resulting executions and hence to build advanced concurrency analysis tools. The approach has been implemented within the GEMOC Studio. We demonstrate how to integrate two representative concurrent meta-programming approaches (MoCCML/Java and Henshin), which use different paradigms and underlying foundations to define an xDSML’s concurrency model. We also demonstrate the ability to define an advanced concurrent omniscient debugger with the proposed protocol. The paper, thus, contributes key abstractions and an associated protocol for integrating concurrent meta-programming approaches in a language workbench, and dynamically exploring the possible executions of a model in the modeling workbench.</p
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