École Supérieure d'Électronique de l'Ouest

Throughout the decades of continuous advances in semiconductor technology, from the discrete devices of the late 1950s to today's billon-transistor system-on-chip, there have always been concerns about the ability of components to operate safely in an increasingly disruptive electromagnetic environment. This paper provides a nonexhaustive review of the research work conducted in the field of electromagnetic compatibility (EMC) at the IC level over the past 40 years. It also brings together a collection of information and trends in IC technology, in order to build a tentative roadmap for the EMC of ICs until the year 2020, with a focus on measurement methods and modeling approaches.

Abstract Rationale Data from population-based cohorts suggest that symptom subtypes and obstructive sleep apnea (OSA)–specific hypoxic burden (HB) could help to better identify patients with OSA at high cardiovascular (CV) risk. Objectives We aimed to evaluate whether those new markers are associated with the risk of major adverse CV events (MACE) in clinical setting. Methods Data from the Pays de la Loire cohort were linked to health administrative data to identify the occurrence of MACE (a composite outcome including all-cause mortality, acute myocardial infarction, stroke, and unplanned coronary revascularization) in patients with newly diagnosed OSA and no overt CV disease. Latent class analysis was used to identify subtypes based on eight clinically relevant variables. HB was defined as the total area under the respiratory event–related desaturation curve. Cox proportional hazards models were used to evaluate the association of symptom subtypes and HB with MACE. Measurements and Main Results Four symptom subtypes were identified (minimally symptomatic [22.0%], disturbed sleep [17.5%], excessively sleepy [49.8%], and moderately sleepy [10.6%]). After a median follow-up of 78 months (interquartile range, 52–109), 592 (11.05%) of 5,358 patients experienced MACE. In a fully adjusted model, HB and overall nocturnal hypoxemia assessed by sleep time with oxygen saturation <90% were the only predictors of MACE (hazard ratio, 1.21; 95% confidence interval, 1.07–1.38; and hazard ratio, 1.34; 95% confidence interval, 1.16–1.55, respectively). The association appeared stronger toward younger patients and women. Conclusion In clinical setting, patients with OSA who demonstrate elevated OSA-specific HB are at higher risk of a CV event and all-cause mortality. Symptom subtypes were not associated with MACE after adjustment for confounders.

A review of recent experimental and theoretical results concerning laser diode self-mixing velocimetry is presented, showing that this technique can be deployed to measure velocity and vibration of solid targets with an extremely simple optical setup. This technique reduces optical alignment problems and achieves results comparable to those obtained by the conventional laser Doppler velocimetry (LDV) approach. It is demonstrated that the self-mixing signal can be processed to recover the target velocity and vibration by applying the same analysis method used for LDV. An optimal signal processing method is then proposed to recover the target velocity with good accuracy, also in the presence of relevant speckle disturbance. Application to the measurement of sub-micron vibrations is also demonstrated, using a self-mixing vibrometer instrument capable of 5-nm accuracy. As an example, the characterization of response and hysteresis of piezoceramic transducers (PZTs) is carried out. These results illustrate the effectiveness of the self-mixing technique in the field of laser velocimetry, opening the way to new applications where compactness and low cost of the measuring apparatus are essential.

A semiconductor laser subject to moderate optical feedback has been used to design an interferometric displacement sensor. The autoadaptative signal processing presented in this paper has been computed in order to improve the accuracy of such a sensor. This setup has been successfully tested for both harmonic and aleatory displacements of a remote piezoelectric actuator with a maximum accuracy of 40 nm

In this study, we have developed a hybrid sensitive rectenna (rectifier + antenna) system at 2.45 GHz. To achieve this system, we have first optimized and validated a zero-bias microwave sensitive rectifier using commercial Schottky diodes. We have then optimized and achieved a 2times2 patch antenna array, which is associated to the microwave rectifier in order to validate the rectenna system, where an RF-dc conversion efficiency of 56% has been observed experimentally. In order to minimize the rectenna dimensions, we have conducted a study using the OMMIC ED02AH 0.20-mum GaAs pseudomorphic high electron-mobility transistor process to develop and achieve a monolithic rectifier at 2.45 GHz with RF-dc conversion efficiency of 65%

In this paper, we present a study of ambient RF energy harvesting techniques. The measurement of the ambient RF power density is presented. The average of the density in broadband (1GHz- 3.5GHz) is in the order of -12dBm/m² (63µW/m²). Two systems have been studied to recover the RF energy. The first is a broadband system without matching circuit. The second is a narrow band system (1.8-1.9GHz) with a matching circuit. The rectifier circuit RF / DC and the choice of the load to optimize the DC power recovered are presented. The preliminary results indicate that the recovered energy is not sufficient to directly power devices but could be stored in a super-capacity or micro-batteries.

This paper proposes a novel, low-profile UWB antenna for wireless body area network (WBAN) applications. The antenna has a polarization perpendicular to the body-free-space interface, which is interesting in order to minimize the coupling into the body. Its structure comprises a modified mono-cone with a top-cross-plate and is coaxially fed through the ground plane. The higher frequency band <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex Notation="TeX">$\vert S _{11} \vert $</tex></formula> performance is due to the mono-cone while the top-cross-plate is responsible for the lower frequency band. This plate also leads to a height reduction when compared to conventional mono-cone antennas. A comprehensive parametric study is done to provide design guidelines. Both frequency- and time-domain results have been measured and presented to validate the design. Results show that the antenna operates from 3.06 to beyond 12 GHz based on <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$\vert S _{11} \vert \le -10~{\hbox {dB}}$</tex></formula> , radiates omni-directionally in the <formula formulatype="inline" xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"><tex Notation="TeX">$H$</tex> </formula> -plane, and has a radiation efficiency over 95%. The system-fidelity factor for UWB signals is adequate for pulse transmission. Finally, the influence of the human proximity on the antenna matching was tested. Results show that its impedance is nearly unchanged as compared to free-space.

Abstract Rationale Randomized controlled trials showed no effect of positive airway pressure (PAP) therapy for obstructive sleep apnea (OSA) on cardiovascular (CV) risk. However, patient selection and low PAP adherence preclude the generalization of their data to clinical samples. Objectives To evaluate the association between hours of PAP use, mortality, and CV morbidity in real-life conditions. Methods Data from the Pays de la Loire Cohort were linked to health administrative data to identify incident major adverse cardiovascular events (MACEs; a composite outcome of mortality, stroke, and cardiac diseases) in patients with OSA who were prescribed PAP. Cox proportional hazards analyses were conducted to evaluate the association between MACEs and quartiles of average daily PAP use over the study period. Measurements and Main Results After a median follow-up of 6.6 years, 961 of 5,138 patients experienced MACEs. Considering nonadherent patients (0–4 h/night) as the reference group, adjusted hazard ratios (95% confidence intervals) for MACEs were 0.87 (0.73–1.04) for the 4–6 h/night group, 0.75 (0.62–0.92) for the 6–7 h/night group, and 0.78 (0.65–0.93) for the ⩾7 h/night group (P = 0.0130). Sensitivity analyses using causal inference approaches confirmed the association of PAP use with MACEs. The association was stronger in male patients (P value for interaction = 0.0004), patients without overt CV disease at diagnosis (P &amp;lt; 0.0001), and those belonging to the excessively sleepy symptom subtype (P = 0.060). Conclusions These real-life clinical data demonstrate a dose–response relationship between PAP adherence and incident MACEs in OSA. Patient support programs may help improve PAP adherence and CV outcomes in patients with OSA.

• Main behaviours of dairy cows were successfully predicted using accelerometer data. • EXtreme Gradient Boosting followed by the Viterbi algorithm led to the best results. • Postures are the most difficult to discriminate with an accelerometer on the neck. • 86 Holstein cows from 4 farms were equipped and observed leading to a large dataset. • Independent signal sequences with a stratification were used to validate the models.

The influence of a left-handed medium (LHM) on the performances of a circular patch antenna is quantified numerically. For this, a homogenization procedure of the LHM is carried out in order to design the patch antenna at a suitable frequency where the losses of the LHM are low. From the first results obtained, it is noted that in the presence of the LHM, the antenna is more directive and has a higher gain.

This paper introduces a complete simulation model of a direct power injection (DPI) setup, used to measure the immunity of integrated circuits to conducted continuous-wave interference. This model encompasses the whole measurement setup itself as well as the integrated circuit under test and its environment (printed circuit board, power supply). Furthermore, power losses are theoretically computed, and the most significant ones are included in the model. Therefore, the injected power level causing a malfunction of an integrated circuit, according to a given criterion, can be identified and predicted at any frequency up to 1 GHz. In addition to that, the relationship between immunity and impedance is illustrated. Simulation results obtained from the model are compared with measurement results, and these demonstrate the validity of this approach.

Abstract Rationale It is currently unclear which patients with obstructive sleep apnea (OSA) are at increased cardiovascular risk. Objective To investigate the value of pulse wave amplitude drops (PWADs), reflecting sympathetic activations and vasoreactivity, as a biomarker of cardiovascular risk in OSA. Methods PWADs were derived from pulse oximetry–based photoplethysmography signals in three prospective cohorts: HypnoLaus (N = 1,941), the Pays-de-la-Loire Sleep Cohort (PLSC; N = 6,367), and “Impact of Sleep Apnea syndrome in the evolution of Acute Coronary syndrome. Effect of intervention with CPAP” (ISAACC) (N = 692). The PWAD index was the number of PWADs (&amp;gt;30%) per hour during sleep. All participants were divided into subgroups according to the presence or absence of OSA (defined as ≥15 or more events per hour or &amp;lt;15/h, respectively, on the apnea–hypopnea index) and the median PWAD index. Primary outcome was the incidence of composite cardiovascular events. Measurements and Main Results Using Cox models adjusted for cardiovascular risk factors (hazard ratio; HR [95% confidence interval]), patients with a low PWAD index and OSA had a higher incidence of cardiovascular events compared with the high-PWAD and OSA group and those without OSA in the HypnoLaus cohort (HR, 2.16 [1.07–4.34], P = 0.031; and 2.35 [1.12–4.93], P = 0.024) and in the PLSC (1.36 [1.13–1.63], P = 0.001; and 1.44 [1.06–1.94], P = 0.019), respectively. In the ISAACC cohort, the low-PWAD and OSA untreated group had a higher cardiovascular event recurrence rate than that of the no-OSA group (2.03 [1.08–3.81], P = 0.028). In the PLSC and HypnoLaus cohorts, every increase of 10 events per hour in the continuous PWAD index was negatively associated with incident cardiovascular events exclusively in patients with OSA (HR, 0.85 [0.73–0.99], P = 0.031; and HR, 0.91 [0.86–0.96], P &amp;lt; 0.001, respectively). This association was not significant in the no-OSA group and the ISAACC cohort. Conclusions In patients with OSA, a low PWAD index reflecting poor autonomic and vascular reactivity was independently associated with a higher cardiovascular risk.

This paper presents a novel maximum power point tracking (MPPT) algorithm, based on genetic algorithms (GA). This algorithm is used for searching the global maximum power point (GMPP) for photovoltaic systems affected by partial shading. The “Perturb and Observe” (P&O) algorithm is embedded into the GA function for improving the optimisation process. By adding this functionality to the algorithm, the number of iterations and the population size is low, thus finding the MPP in a short time. Description of this algorithm and its performances will be detailed in this article, verified through simulation and experimental results.

A new, global inversion is used to estimate the large scale oceanic circulation based on the World Ocean Circulation Experiment and Java Australia Dynamic Experiment hydrographic data. A linear inverse "box" model is used to combine consistently the transoceanic sections. The circulation is geostrophic with an Ekman layer at the surface and oceanic layers defined by neutral surfaces. Near-conservation of mass, salt and top-to-bottom silica is required and, in addition, heat and the phosphate-oxygen combination (170[P04]+[02]) are conserved in layers that are not in contact with the surface. A globally-consistent solution is obtained for a depth-independent adjustment to the thermal wind field, freshwater flux divergenees, the Ekman transport, and the advective and diffusive dianeutral fluxes between layers. A detailed error budget permits calculation of statistical uncertainties, taking into aeeount both the non-resolved part of the solution and the systematie errors due to the temporal oeeanic variability. The estimated water mass transports during the WOCE period (1985)(1986)(1987)(1988)(1989)(1990)(1991)(1992)(1993)(1994)(1995)(1996) are generally similar to previous published estimates. However, important differenees are found. In particular, the inflow of bottom waters into the Paeifie Ocean is smaller than in most previous estimates. Utilization of property anomaly conservation constraints allows the estimation of significant dianeutral diffusivities in deep layers, with a global average of 3 lcm 2 s-1 north of 30 0 S. Dianeutral transfers indieate that about 20 Sv of bottom water is formed in the Southern Ocean. Significant oceanatmosphere heat fluxes are found, with a global heating of 2.3 0.4 PW in the tropical band and a corresponding eooling at high latitudes. The signature of a large-seale average export production is found for nutrients in several temperate regions. Despite the large uncertainties, the production magnitudes are consistent with independent measurements from sediment traps and isotopic data. Net nutrient sources or sinks are found in several regions, suggesting either transport of dissolved organic matter or a seasonal alias. Oxygen indicates large exchanges with the atmosphere, with intake at high latitudes and outgassingjremineralization at low latitudes.

En Galve (Teruel) hay más de 50 localidades con restos de vertebrados continentales en las Formaciones Higueruelas (Titónico), Villar del Arzobispo (Titánico superior-Berriasiense medio), El Castellar (Hauteriviense terminal-Barremiense basal) y Camarillas (Barremiense inferior). Por tanto, «Galve» no es un único yacimiento de vertebrados mesozoicos, sino una localidad con numerosos yacimientos de vertebrados del intervalo Titónico-Barremiense, que geológicamente pertenecen a la Cuenca cretácica inferior del Maestrazgo (Cordillera Ibérica Central), Subcuenca de Galve. La mayor parte de los yacimientos contienen restos óseos, pero también son abundantes los yacimientos paleoicnológicos y paleoológicos. Los vertebrados mejor conocidos son los mamíferos y dinosaurios, aunque también hay estudios sobre los tiburones, peces óseos, anfibios, escamosos y cocodrilos. Algunos grupos, como tortugas y pterosaurios, permanecen prácticamente sin estudiar. Galve es la localidad tipo de varios taxones de vertebrados: el tiburón Lonchidion microselachos, el anfibio Galverpeton ibericum, el dinosaurio Aragosaurus ischiaticus, los mamíferos Galveodon nannothus, Lavocatia alfambrensis, Eobaatar hispanicus, Parendotherium herreroi, Spalacotherium henkeli y Pocamus pepelui, y la cáscara de huevo de dinosaurio Macroolithus turolensis. Es este trabajo se revisa el estado de conocimientos sobre los vertebrados de Galve, y se actualiza la lista faunística de sus yacimientos, siendo la primera vez que se realiza teniendo en cuenta la distribución estratigráfica de los taxones.

<b>Indices of sleep apnoea-related hypoxic burden and heart rate variability derived from full-night polysomnography might be useful for identifying sleep apnoea patients at risk for stroke</b>https://bit.ly/3eIYVsc

In the field of civil engineering, sounding the pavement layers is classically performed using standard ground-penetrating radar, whose vertical resolution is bandwidth dependent. The layer thicknesses are deduced from both the time delays of backscattered echoes and the permittivity of layers. In contrast with conventional spectral analysis approaches, this letter focuses on one of the machine learning algorithms, namely, the support vector machine, to perform time delay estimation and dielectric constant estimation of the medium from backscattered radar signals. This letter shows the super time resolution capability of such technique to resolve overlapping and fully correlated echoes within the context of thin pavement layer testing.

We present the development of an illustrative example of e-business based on two different applications of a Model-Driven Architecture (MDA) approach. In the first application, the platform-independent model (PIM) is created using the Unified Modeling Language (UML). This PIM is transformed using Atlas Transformation Language (ATL) to generate the platform-specific model (PSM) based on three target platforms: Java, Web service and Java Web service developer pack (JWSDP). In the second application, the PIM is created using enterprise distributed object computing (EDOC) and transformed into another PSM based on the same target platforms. For this purpose we use the illustrative example of a travel agency to depict some issues of the approach. Then, we discuss mappings between meta-models.

An ultrasonic method providing for an efficient global detection of defects in complex media (multiple scattering or reverberating media) is reported herein; this method is based on the nonlinear acoustic mixing of coda waves (stemming from multiple scattering) with lower frequency-swept pump waves. Such a nonlinear mixing step is made possible by the presence of nonlinear scatterers, such as cracks and delamination, yet remains absent when the waves are scattered only by linear scatterers, as is the case in a complex but defect-free medium. A global inspection is achieved thanks to the use of wide-band coda and pump signals, which ensure the excitation of many resonances along with a homogeneous acoustic energy distribution in the medium. We introduce the existing sensitivity tools developed for Coda Wave Interferometry in extracting the pump amplitude-dependent parameters of the coda waves associated with effective nonlinear parameters of the medium. By comparing results at two damage levels, these effective nonlinear parameters are shown to be correlated with crack presence in glass samples. The mechanisms potentially responsible for the observed amplitude dependence on the tested elastic parameters and waveform modification are discussed.

This article aims at providing a framework for assessing the detection and localization performance of guided wave–based structural health monitoring imaging systems. The assessment exploits a damage identification metric providing a diagnostic of the structure from an image of the scatterers generated by the system, allowing detection, localization, and size estimation of the damage. Statistical probability of detection and probability of localization curves are produced based on values of the damage identification metric for several damage sizes and positions. Instead of relying on arduous measurements on a significant number of structures instrumented in the same way, a model-based approach is considered in this article for estimating probability of detection and probability of localization curves numerically. This approach is first illustrated in a simplistic model, which allows characterizing the robustness of the structural health monitoring system for various levels of noise in test signals. An experimental test case using a more realistic case with an artificial damage is then considered for validating the approach. A good agreement between experimental and numerical values of the damage identification metric and derived probability of detection and probability of localization curves is observed.