Dependability investigation of wireless short range embedded systems: hardware platform oriented approach

A new direction in short-range wireless applications has appeared in the form of high-speed data communication devices for distances of hundreds meters. Behind these embedded applications, a complex heterogeneous architecture is built. Moreover, these short range communications are introduced into critical applications, where the dependability/reliability is mandatory. Thus, dependability concerns around reliability evaluation become a major challenge in these systems, and pose several questions to answer. Obviously, in such systems, the attribute reliability has to be investigated for various components and at different abstraction levels. In this paper, we discuss the investigation of dependability in wireless short range systems. We present a hardware platform for wireless system dependability analysis as an alternative for the time consuming simulation techniques. The platform is built using several instances of one of the commercial FPGA platforms available on the market place. We describe the different steps of building the wireless hardware platform for short range systems dependability analysis. Then, we show how this HW platform based dependability investigation framework can be a very interactive approach. Based on this platform we introduce a new methodology and a flow to investigate the different parts of system dependability at different abstraction levels. The benefits to use the proposed framework are three fold: first, it takes care of the whole system (HW/SW -digital part, mixed RF part, and wireless part); Second, the hardware platform enables to explore the application’s reliability under real environmental conditions taking into account the effect of the environment threats on the system; And last, the wireless platform built for dependability investigation present a fast investigation approach in comparison with the time consuming co-simulation technique

Iterative Reconstructions in Reduced-Dose CT: Which Type Ensures Diagnostic Image Quality in Young Oncology Patients?

To compare adaptive statistical iterative reconstruction (ASIR) and model-based iterative reconstruction (MBIR) algorithms for reduced-dose computed tomography (CT). Forty-four young oncology patients (mean age 30 ± 9 years) were included. After routine thoraco-abdominal CT (dose 100%, average CTDI javax.xml.bind.JAXBElement@e7f585f 9.1 ± 2.4 mGy, range 4.4-16.9 mGy), follow-up CT was acquired at 50% (average CTDI javax.xml.bind.JAXBElement@2e35610f 4.5 ± 1.2 mGy, range 2.2-8.4 mGy) in 29 patients additionally at 20% dose (average CTDI javax.xml.bind.JAXBElement@37ad3473 1.9 ± 0.5 mGy, range 0.9-3.4 mGy). Each reduced-dose CT was reconstructed using both ASIR and MBIR. Four radiologists (two juniors and two seniors) blinded to dose and technique read each set of CT images regarding objective and subjective image qualities (high- or low-contrast structures), subjective noise or pixilated appearance, diagnostic confidence, and lesion detection. At all dose levels, objective image noise was significantly lower with MBIR than with ASIR (P < 0.001). The subjective image quality for low-contrast structures was significantly higher with MBIR than with ASIR (P < 0.001). Reduced-dose abdominal CT images of patients with higher body mass index (BMI) were read with significantly higher diagnostic confidence than images of slimmer patients (P < 0.001) and had higher subjective image quality, regardless of technique. Although MBIR images appeared significantly more pixilated than ASIR images, they were read with higher diagnostic confidence, especially by juniors (P < 0.001). Reduced-dose CT during the follow-up of young oncology patients should be reconstructed with MBIR to ensure diagnostic quality. Elevated body mass index does not hamper the quality of reduced-dose CT

Multiobjective optimization model for scheduling of construction projects under extreme weather

Extreme weather significantly impacts construction schedules and costs and can be a source of schedule delays and budget overruns. A multi-objective optimization model, presented herein for the scheduling of construction projects under extreme weather conditions, can generate optimal/near optimal schedules that minimize the time and cost of construction projects in extreme weather regions. The model computations are organized as follows: (1) a scheduling module for developing practical schedules for construction projects, (2) a cost module for computing total project cost, and (3) a multi-objective module for determining optimal/near optimal trade-offs between project time and cost. Two practical examples of the effects of extreme weather on construction time and direct cost are provided, the first of which shows the impact of extreme weather on construction time and cost, and the second of which demonstrates the ability of the model to generate and visually present the optimal trade-offs between the duration and costs of construction projects under extreme weather conditions.Scopu

Scalable Multi-FPGA Platform for Networks-On-Chip Emulation

ISBN : 978-1-4244-1027-4International audienceInterconnect validation is an important early step toward global SoC (System-On-Chip) validation. Fast performances evaluation and design space exploration for NoCs (Networks-On-Chip) are therefore becoming critical issues. A significant speedup of the global validation process for NoC-centric SoCs could be achieved by prototyping such systems on reconfigurable devices (FPGA). However, as SoC complexity increases with the technology scaling, existing general purpose prototyping platforms are far from being suited for large systems. In this paper we present a study for a scalable multi-FPGA platform, designed for NoCs emulation and debugging. This platform allows the integration of complete systems as well as a near cycleaccurate performance estimation

Prototypage d’Applications POSIX sur une architecture

National audienc

Networks-In-Package: Performances management and design methodology

ISBN : 978-1-4244-1616-5International audienceNowadays large scale MPSoC designs embedding multiple processors, memories and specialized IPs require high integration densities which can not be met at an acceptable cost within the standard single-chip technology. The systems-in-package (SiP) approach has been proposed then as an alternative which enables such integration requirements. Even though analysis of systems-in-package design techniques shows large similarities with standard techniques for multi-chip-modules (MCM), there is a huge methodological lack for communication-centric MPSoCs. In this paper we motivate the need for new design methodologies which addresses the various problems of the emerging NiP (networks-in- package) paradigm with a special focus on performances considerations. We also propose a complete NoC architecture (MS-NoC) and a design flow aimed at helping designers to build NiP architectures

Trickle++: A Context‐Aware Trickle Algorithm

International audienceWe propose to augment the Trickle algorithm with contextual information freely and locally available in low-power wireless networking technologies. The aim is to equip Trickle with hints and heuristics allowing it to propagate updates faster using link indicators such as received signal strength and link quality indicators along with available neighbourhood and network state information. The proposed augmentations are carefully designed so to preserve Trickle strengths in terms of simplicity, reliability, scalability, and load balancing while minimising its latency. Extensive simulation evaluations, conducted under TinyOS, show that the resulting algorithm, dubbed Trickle++, propagates updates more than twice faster than Trickle. Obtained results also show that Trickle++ preserves Trickle performance regarding overhead, load balancing, and code footprint