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International audience; For display applications, high current and large on/off current ratio are pursued for driving and switching transistors. In this article, a thin film transistor (TFT) device incorporating a buried electrode is proposed, which enables increasing the driving current by reducing the channel length, with the channel length only at the drain side. This lateral short-channel TFT enables increasing the on-current while maintaining the field effect mobility, in comparison to our experimental short-channel vertical TFT structure. Another advantage of the proposed structure lies in the suppression of the Schottky barrier at the source and drain contacts when using high-work-function source/drain contacts for an N-type TFT, with an increased on/off current ratio reaching approximately 106. The suppression of Schottky barrier at the source/drain has been verified by the contact resistance measurements. Even though high driving current is obtained, the off-current is still high due to the weakened electric field at the source/drain sides and needs to be further optimized.

International audience; Numerous researches have been done on the Shewhart X chart based on the average run length (ARL) metric. Since the shape of the run length (RL) distribution changes with the mean shift size, the median run length (M RL) is argued to be a better criterion for evaluating the performance of the Shewhart X chart. Moreover, when the process parameters are unknown, the Phase II properties of the Shewhart X chart are conditioned on the parameter estimates arising from different practitioners in Phase I. This variability among the estimated process parameters is usually called as the between-practitioners variability. In order to investigate this variability in the conditional M RL values, both the average M RL (AM RL) and the standard deviation of M RL (SDM RL) will be used together in our article. The performance analyses of the M RL based

International audience; Exponentially weighted moving average (EWMA) control charts for time-between-events (TBE) are commonly suggested to monitor high-quality manufacturing processes for the early detection of process deteriorations. In this study, an enhanced one-sided EWMA TBE control chart is developed for rapid detection of increases or decreases in the process mean. The use of the truncation method helps to improve the sensitivity of the proposed scheme in the process mean detection. Moreover, by taking the effects of parameter estimation into account, the proposed scheme with estimated parameters is also investigated in this paper. Both the average run length (ARL) and standard deviation of run length (SDRL) performances of the proposed scheme with known and estimated parameters are studied using the Markov chain method, respectively. Furthermore, an optimal design procedure is developed for the recommended one-sided EWMA TBE chart based on ARL. Numerical results show that the proposed optimal one-sided EWMA TBE chart is more sensitive than the existing optimal one-sided exponential EWMA chart in monitoring both upward and downward mean shifts. Meanwhile, it also performs better than the existing comparative scheme in resisting the effect of the parameter estimation. Finally, two illustrative examples are considered to show the implementation of the recommended one-sided EWMA TBE scheme for simulated and real datasets. For the real dataset of F-16 aircraft, the accident occurrences of F-16 are very low, in which case monitoring the time between two successive F-16 accidents is more efficient than the traditional monitoring schemes. Moreover, the usage of the truncation method makes the proposed one-sided EWMA TBE chart more appropriate for monitoring those two datasets with known shift directions, and the operation of the proposed scheme is simple which does not need to predetermine the reflecting boundary of the existing comparative scheme.

In this letter, we investigate the uplink of a reconfigurable intelligent surface (RIS)-aided millimeter-wave (mmWave) multi-user system. In the considered system, however, problems with hardware cost and power consumption arise when massive antenna arrays coupled with power-demanding analog-todigital converters (ADCs) are employed. To account for practical hardware complexity, we consider that the access point (AP) is equipped with resolution-adaptive analog-to-digital converters (RADCs). We maximize the achievable rate under hardware constraints by jointly optimizing the ADC quantization bits, the RIS phase shifts, and the beam selection matrix. The formulated problem is non-convex. To efficiently tackle this problem, a block coordinated descent (BCD)-based algorithm is proposed. Simulations demonstrate that an RIS can mitigate the hardware loss due to the use of RADCs, and that the proposed BCD-based algorithm outperforms state-of-the-art algorithms., European Union (EU); Horizon 2020; European Commission (EC); ARIADNE Project; RISE-6G Project; Scientific and Technological Research Council of Turkey (TÜBİTAK); National Key Research and Development Program of China; National Natural Science Foundation of China (NSFC); Alibaba-NTU Singapore Joint Research Institute (JRI)

International audience; An organic ambipolar charge trapping non-volatile memory device is proposed based on tris(8-hydroxy quinoline) aluminum(Alq3)/ fullerene(C60)/pentacene double heterojunctions. The double heterojunctions were analyzed and compared with the sole heterojunction. Even though the Alq3/pentacene sole heterojunction shows a negative threshold voltage shift for programming under negative biasing, light illumination is required to efficiently erase. In contrast, for C60/pentacene sole heterojunction, the negative shift of threshold voltage is observed even with a positive erasing voltage. By combining the two trapping layers, a large memory window with fully-electrical programming and erasing is obtained. The efficient programming and erasing of the double heterojunctions structure are analyzed, sufficient electrons can be injected that enables the electrical erasing, and the negative shift of the threshold voltage under positive erasing voltage for the C60/pentacene structure is suppressed due to the suppression of the large built-in potential for the sole heterojunction, which can be verified by a large positive shift for the pentacene/C60/pentacene double heterojunctions.

Electron symmetry determines many important properties of molecules, from selection rules for photoelectron spectroscopy to symmetry selection rules for chemical reactions. The original electron symmetry is broken if a laser pulse changes the initial state, typically the ground state g, to a superposition of g and an excited state e with different irreducible representations (IRREPs). Quantum dynamics simulations for two examples, the oriented benzene and LiCN molecules, show that the original electron symmetry can be restored by means of a reoptimized π-laser pulse which transfers the component in the excited state e to another state e', or to several others with the same IRREP as the ground state. This method lends itself to much easier experimental applications than all previous ones because it allows the healing of electron symmetry immediately, without any attosecond constraint on the timing of the second pulse.

International audience; The Poisson distribution assumption often arises in several industrial applications for modeling defects or non-conformities. In this work, we investigate the one-and two-sided performance of a new adaptive EWMA (Exponentially Weighted Moving Average)-type chart for monitoring Poisson count data. An appropriate discrete-state Markov chain technique is provided to compute the exact ARL (Average Run Length) properties. Moreover, comparative studies are conducted to demonstrate the higher sensitivity of the proposed chart in the detection of shifts with various magnitudes. Advices on how to select the appropriate chart parameters are provided and an illustrative numerical example is proposed.

International audience; The usual practice in Statistical Process Monitoring techniques assumes that the data distribution is known and the related parameters are accurately estimated. In practice, the underlying distribution and its parameters are rarely known, and control charts need to be constructed with parameters being estimated. Such issues have recently received an increasing attention in evaluating the properties of both parametric and nonparametric charts. However, the same study is seldom conducted for the control charts based on the data-driven tools. In this paper, we investigated the in-control performance of a nonparametric control chart based on the Support Vector Data Description (SVDD) theory. More specifically, we discuss the conditional effect of the training Phase-I samples on the Phase-II efficiency when different distributions are considered. Simulation results show that the conditional performance of the SVDD-based chart can be strongly affected by the Phase-I samples. It this situation, adjusted control limits with a specific number of available training sample is suggested.

International audience

International audience; Exponential type charts are useful tools to monitor the time between events in high-quality processes with a low defect rate. Most studies on exponential charts are 1 designed with the average run length (ARL) metric. The only use of ARL in the design of control charts is sometimes criticized because the shape of the run length (RL) distribution of control charts changes with the shift size. In fact, the RL distribution of the exponential exponentially weighted moving average (EWMA) chart is skewed, especially when the process is in-control. Hence, the median run length (M RL) serves as a more meaningful indicator. Moreover, in some situations, the shift size in the process is unknown in advance. Under this case, the expected median run length (EM RL) can be used as the metric. In this paper, the RL properties of both the upper-and lower-sided exponential EWMA charts are studied through a Markov chain approach. Two optimal design procedures are developed for one-sided exponential EWMA charts based on the M RL and EM RL, respectively. The choices of reflecting boundaries for one-sided exponential EWMA charts are discussed through many numerical studies. The M RL and EM RL performances of the one-sided exponential EWMA charts are investigated.

International audience; In order to provide a balanced protection against a range of shift sizes in high-quality processes, a new one-sided adaptive truncated exponentially weighted moving average (ATEWMA) control chart with known and estimated parameters is developed for monitoring time between-events (TBE) data. A dedicated Markov chain model is established for evaluating the run length properties in known and estimated parameters operating conditions. Furthermore, a two-stage optimal design procedure of the proposed scheme is developed based on the average run length (ARL) criteria. Simulation results show that the one-sided ATEWMA TBE scheme with known parameters is superior to its competitors in detecting both upward and downward shifts. Finally, two real data applications are employed to show the implementation of the recommended scheme in the monitoring of TBE data.

International audience; One-sided type schemes are known to be more appropriate for monitoring a process when the direction of a potential mean shift can be anticipated. Furthermore, if the magnitude of the potential mean shift is unknown, it is desired to design a control chart to perform well over a wide range of shifts instead of only optimizing its performance in monitoring a particular mean shift level. The one-sided adaptive truncated exponentially weighted moving average (ATEWMA) X scheme recommended in this paper is a control chart that combines a Shewhart X scheme and a new one-sided EWMA X scheme together in a smooth way for rapidly detecting the upward (or downward) mean shifts. The basic idea of the recommended one-sided ATEWMA X scheme is to truncate the observations (i.e., the sample means X) first, and then to dynamically weight the past observations according to a suitable function of the current prediction error. This helps to improve the sensitivity of the proposed one-sided ATEWMA X scheme for detecting both small and

International audience; The polycrystalline silicon vertical thin-film transistors (TFTs) with different active layer thicknesses of 150 and 300 nm were fabricated by a five-mask process and electrically characterized. The vertical TFT with 150-nm active layer thickness shows comprehensive advantages over its counterpartwith 300-nm active layer, especiallywith a higher ON/OFF current ratio I-ON/I-OFF of more than 10(6) and higher field-effectmobility, excluding the access resistance effect. The electrical parameters were analyzed by the density of states (DOS) calculation, and smallerDOS is deduced for the device with 150-nm active layer for the same energy level. The detailed elucidation of the DOS was analyzed by introducing the intrinsic mobility and the grain boundary barrier height at the flat-band state, which gives the detailed expressions for the DOS. Polycrystalline silicon lateral TFT was also introduced to verify this evaluationmethod.

International audience; This paper proposes a cascade blockage model for analyzing the vision that a user has of a wireless network. This model, inspired by the classical multiplicative cascade models, has a radial structure meant to analyze blockages seen by the receiver at the origin in different angular sectors. The main novelty is that it is based on the geometry of obstacles and takes the joint blockage phenomenon into account. We show on a couple of simple instances that the Laplace transforms of total interference satisfies a functional equation that can be solved efficiently by an iterative scheme. This is used to analyze the coverage probability of the receiver and the effect of blockage correlation and penetration loss in both dense and sparse blockage environments. Furthermore, this model is used to investigate the effect of blockage correlation on user beamforming techniques. Another functional equation and its associated iterative algorithm are proposed to derive the coverage performance of the best beam selection in this context. In addition, the conditional coverage probability is also derived to evaluate the effect of beam switching. The results not only show that beam selection is quite efficient for multi-beam terminals, but also show how the correlation brought by blockages can be leveraged to accelerate beam sweeping and pairing.

International audience; Exponentially weighted moving average (EWMA) type charts are very popular and efficient in monitoring various kind of statistics. Much researches have been done on the EWMAX chart with known process parameters. But, in practice, the process parameters used to set the control chart limits are often unknown and they need to be estimated from different Phase I samples. Moreover, because the shape of the run length distribution for the EWMAX chart changes with the mean shift, the median 1 run length (M RL) can serve as a good alternative to evaluate the performance of the EWMAX chart. In this article, we will investigate the conditional properties of the EWMAX chart with unknown process parameters based on the M RL metric. In order to investigate the chart's properties, the average M RL (AM RL) and the standard deviation of M RL (SDM RL) will be used together when the process parameters are unknown. To prevent too many lower in-control M RL values, the adjusted control limits of the M RL based EWMA chart are obtained by using a bootstrap type approach and the results show that the adjusted control limits can give a good tradeoff between the in-control and out-of-control M RL performances.

International audience; This article is concerned with further studies on state estimation of discrete-time nonlinear parameter varying systems with the help of an efficient multiinstant switching observer. First, a pair of variable weights for different sampling instants are introduced and thus more featured switching modes for the applied observer are produced by updating and utilizing all the varying elements that vary upon time. Second, an individual designing condition of the developed multiinstant switching observer for each switching mode is derived by considering the specific information of the updated varying elements, respectively. Indeed, the whole obtained result is less conservative than the previous ones. Finally, some comparative simulations are provided in order to illustrate the advantage and benefit of the developed results.

P and N type polycrystalline silicon has been applied in thin film transistors (TFTs) for driving a range of displays, and for building up complementary metal oxide semiconductor (CMOS)-like circuits. In one aspect, the high driving current is required, which is usually achieved by improving field effect mobility of the active layer. For another, balanced electrical characteristics are required for achieving CMOS-like logic circuits. In this article, in order to increase driving current, P and N type polycrystalline silicon vertical TFTs configuration is proposed that can get rid of the strict requirement of the field effect mobility in order to increase the driving current. In addition, the balanced electrical properties are demonstrated for P and N type vertical TFTs, which are elucidated by the density of states calculations. The simple Simulation Program with Integrated Circuit Emphasis (SPICE) modelling indicates the potential application in CMOS inverter based on our vertical TFTs.

In high-quality processes, events related to non-quality rarely occur and the times between these events (TBE) is likely to follow a skewed distribution like the gamma distribution. In order to mon...

International audience; Reconfigurable Intelligent Surfaces (RIS) have been a hot research topic in recent years, being widely advocated to represent a promising technology for beyond 5G cellular networks. In this paper, we propose a modulation scheme called RIS-IM in which Index Modulation (IM) is applied using RIS. However, to overcome the strong channel correlation caused by the small separation distance between the RIS elements a precoding stage based on the concept of signature constellations is added at the transmitter. The precoding stage is shown to counteract the degradations caused by these correlations providing interesting gains. We further improve the performance by passive beamforming, optimizing the phase shifts of the RIS elements using Semidefinite Programming (SDP) to improve the receiver SNR. We then provide performance analysis for this IM scheme using computer simulations. A comparison of RIS-IM with Spatial Modulation (SM), which is another member of the IM family, is also included, showing that RIS-IM provides substantial SNR gains.

International audience; This paper investigates the uplink dimensioning problem for OMA (Orthogonal Multiple Access) and NOMA (Non-Orthogonal Multiple Access) schemes. Dimensioning is to make radio resource provision for a service area to fulfill an outage constraint. The radio resource limit and outage in dimensioning make classical inhomogeneous Poisson assumption of uplink served user point process questionable. In this paper, we first prove that this process admits a homogeneous Poisson distribution in the limiting regime. As a consequence, uplink coverage probabilities over log-normal shadowing for both schemes are derived. Then, tractable stochastic geometry models for two schemes are proposed to obtain numbers of total required radio blocks. Their upper bounds under an outage constraint are also given to reduce computing overhead. Finally, the simulations confirm accuracy of derivations and demonstrate the effectiveness of our models.

International audience; A polycrystalline silicon vertical thin film transistor (VTFT) is fabricated, and the electrical parameters are extracted and compared with the typical lateral thin film transistor (LTFT). The similar subthreshold slope and the distinct field effect mobility is verified by the DOS calculation in the deep and shallow trap regions, respectively, and in this article, it is used to compare with the grain boundary trap density at a lower Vds = 10 mV that eliminates the velocity saturation effect. The accurate threshold voltage is also calculated by a systematic model including the grain boundary barrier modulation effect. A pseudo-subthreshold region is demonstrated, and the threshold voltage exactly corresponds to the 3kT point of the grain boundary barrier. The low field effect mobility of VTFT is mainly due to the small grain size and also slightly affected by the parasitic resistance, which can be improved by optimizing the processing conditions, especially by improving the sidewalls smoothness and the active layer quality.

International audience; Due to the cost-effective advantage, range-free localization schemes are attractive for low-cost Internet of Things applications. As a distinguishing range-free scheme, DV-Hop localization can localize those unknown nodes which have less than 3 or even no neighbor anchors. However, the localization results by existing DV-Hop based algorithm are found to be inconsistent with the real connectivity between nodes. The inconsistency inspires us to propose two algorithms to improve localization accuracy. First a Centralized Connectivity-based DVHop (CCDV-Hop) algorithm is proposed to optimize the accuracy of DV-Hop localization. Establishing an optimization problem which takes the real connectivity between any two nodes as the constraints, the proposed algorithm can make the localization results conform to the real connectivity. Then an algorithm with lower complexity is proposed, namely Distributed Connectivitybased DV-Hop (DCDV-Hop) algorithm, which can obtain nearoptimal localization performance in distributed networks. Without including the connectivity of all nodes, the constraints in the proposed DCDV-Hop algorithm only consider the real connectivity within two hops. Simulation results show that despite higher complexity, the proposed algorithms can achieve much better accuracy than other DV-Hop based methods.

International audience; Amorphous thin films from solution-processable semiconductors are key materials for low-cost and large area optoelectronics. Design rules toward novel amorphous compounds with outstanding light emission and light amplification properties require understanding of the intimate relation between chemical and electronic structure. Here, a series of compounds with tunable electronic transition characters of the lowest excited state, from local excited (LE), hybrid local charge-transfer (HLCT) to charge-transfer (CT) character is delicately designed. By deploying a combination of computational calculations and femtosecond-transient absorption experiments, it is shown that pure LE states strongly coupled to high wavenumber vibrational modes favor to form a few dominant discrete vibrational levels and are essential for optical gain, whereas HLCT or CT states are preferably coupled to low frequency vibrational modes and form a large number of consecutive vibrational levels which lead to broad excited-state absorption overwhelming stimulated emission. The results provide guidelines for the rational design of efficient organic laser materials.

In practice, different practitioners will use different Phase I samples to estimate the process parameters, which will lead to different Phase II control chart's performance. Researches ref...

Thermally sprayed coatings are manufactured by molten or semi-molten droplets impinging onto the target substrate. The properties of coatings created (porosity, conductivity, cracks, ...) depend largely on the dynamics of the droplets which is an outcome of joint aspects, such as properties of liquid droplet and surface wettability. The present work investigates the normal impact of liquid droplets (molten ceramic or metallic droplets) onto dry solid surfaces of various wetting properties. Use is made of the Volume-Of-Fluid (VOF) interface tracking method with a single set of mass and momentum conservation equations. The wettability of a solid surface, characterised by a contact angle, is taken as part of the boundary conditions in the Smooth VOF algorithm. Introducing the dimensionless time t* = tV 0/D0 for a droplet with the initial speed V 0 and initial diameter D0, its spread factor ξ (= D/D0) is found to be proportional to the square root of t* when 0.2 t * ≥ 0.5 W e .

International audience; In this study, a multifunctional acoustic metastructure is proposed to achieve both effective low-frequency sound isolation and acoustic energy harvesting. A metallic substrate with proof mass is adopted to generate the local resonant phenomenon for the purpose of overcoming the drawbacks of the previous rubber film-based acoustic metastructure; the latter usually requires an elaborate tension process. Numerical simulations show that the proposed structure exhibits excellent noise isolation performance in the low-frequency band. Meanwhile, the incident sound energy can be converted into electrical energy with the help of an added piezoelectric patch. Numerical simulation results indicate that the harvested energy can reach the mW level. The parameters\textquotesingle influence on the metastructure\textquotesingle s vibro-acoustic and energy harvesting performance are discussed in detail. An optimized configuration is selected and used for experimental study. It is demonstrated that 0.21 mW electrical power at 155 Hz can be harvested by the proposed metastructure under 114 dB sound pressure excitation.

Massive MIMO is considered as one of the key enablers of the next generation 5G networks.With a high number of antennas at the BS, both spectral and energy efficiencies can be improved. Unfortunately, the downlink channel estimation overhead scales linearly with the number of antenna. This does not create complications in Time Division Duplex (TDD) systems since the channel estimate of the uplink direction can be directly utilized for link adaptation in the downlink direction. However, this channel reciprocity is unfeasible for the Frequency Division Duplex (FDD) systems where different physical transmission channels are existent for the uplink and downlink. In the aim of reducing the amount of Channel State Information (CSI) feedback for FDD systems, the promising method of two stage beamforming transmission was introduced. The performance of this transmission scheme is however highly influenced by the users grouping and selection mechanisms. In this paper, we first introduce a new similarity measure coupled with a novel clustering technique to achieve the appropriate users partitioning. We also use graph theory to develop a low complexity groups scheduling scheme that outperforms currently existing methods in both sum-rate and throughput fairness. This performance gain is demonstrated through computer simulations., 7 pages, 6 figures

This paper presents a new concept, supported by 3-D TCAD simulations, for improving the performance and subthreshold swing (SS) of enhancement-mode AlGaN/GaN fin-shaped field-effect transistors (FinFETs). By choosing appropriate device parameters, the formation of 2-D electron gas (2DEG) can be delayed such as to ensure simultaneous activation of 2DEG and sidewall MOS channels at positive threshold voltage for normally off operation. The 2DEG channel starts forming in the middle of the fin, whereas the edges are depleted by the lateral MOS gates. Not only increasing the gate voltage does the 2DEG charge increase, but also the effective width is enlarged being less depleted by the gates. This double-2DEG mechanism adds to the regular MOS channels on the sidewalls and enables enhanced performance. The 3-D TCAD simulations indicate that narrow FinFET (20 nm) can exhibit excellent switching characteristics: very low SS of 55 mV/decade, below the 60 mV/decade limit, high on/off current ratio of 1010, and good current driving capability due to the added 2DEG channel contribution. The maximum transconductance is 350 mS/mm, the drain current reaches 380 mA/mm, and the on resistance is as low as 0.018 $\text{m}\Omega \cdot \text {cm}^{2}$ .

session 4: Memory Devices; International audience; A systematic study to model and characterize the band-modulation Z 2 -FET device is developed. Emphasis is given on the effect of carrier lifetime which is the key parameter. It provides guidelines to design Z 2 -FETs for sharp switching, ESD protection and 1T-DRAM applications. We provide new insights of the relation between carrier generation/recombination and electrostatic barriers.

The authors thank T. Chauveau (LSPM) for help with Rietveld analysis, A. Jamali (LRCS) for assistance with SEM measurements, and Drs. Y. Tange (SPring-8) and N. Guignot (SOLEIL) for help in synchrotron experiments that were carried out during beamtimes allocated to proposals 2017A1047 & 2018A1121 at SPring-8 and proposal 20170092 at SOLEIL. Ab initio calculations have been performed using Rurik and Arkuda supercomputers. This work was financially supported by the European Union’s Horizon 2020 Research and Innovation Programme under Flintstone2020 project (grant agreement No. 689279). Z.W. thanks the National Science Foundation of China (grant No. 11604159). A.R.O. thanks the Russian Ministry of Science and Higher Education (grant 2711.2020.2 to leading scientific schools)., New boron-rich sulfde B6S and selenide B6Se have been discovered by combination of high pressure – high temperature synthesis and ab initio evolutionary crystal structure prediction, and studied by synchrotron X-ray difraction and Raman spectroscopy at ambient conditions. As it follows from Rietveld refnement of powder X-ray difraction data, both chalcogenides have orthorhombic symmetry and belong to Pmna space group. All experimentally observed Raman bands have been attributed to the theoretically calculated phonon modes, and the mode assignment has been performed. Prediction of mechanical properties (hardness and elastic moduli) of new boron-rich chalcogenides has been made using ab initio calculations, and both compounds were found to be members of a family of hard phases., Horizon 2020 Framework Programme 689279 Ministry of Science and Higher Education of the Russian Federation 2711.2020.2 National Natural Science Foundation of China 11604159 Center of Excellence has received funding from the European Union’s Horizon 2020 Framework Programme H2020-WIDESPREAD-01-2016-2017-TeamingPhase2 under grant agreement No. 739508, project CAMART²

International audience; In 1986, some examples of algebraic, and nonquadratic, power series over a fi?nite prime ?field, having a continued fraction expansion with partial quotients all of degree one, were discovered by W. Mills and D. Robbins. In this note we show how these few examples are included in a very large family of continued fractions for certain algebraic power series over an arbitrary ?finite fi?eld of odd characteristic.

International audience; Vertical double-gate (DG) FinFETs fabricated on SOI wafers show good gate control, reasonable threshold voltage and high carrier mobility despite the absence of the top-gate. The 3D coupling effect between the two lateral-gates and the back-gate is investigated based on experimental and simulation results. We compare DG and triple-gate FinFETs with various fin widths. Front-channel characteristics are easily tuned by applied bias at the back-gate if the fin is not too narrow. We highlight that vertical DG FinFET is more appropriate device for dynamic threshold voltage adjustment than triple-gate FinFET. An analytical model is proposed to quantify the coupling effect in DG FinFET by solving 2D Poisson equation. The body potential profile and coupling effect are modeled. A very good agreement is obtained between experiments, 3D simulations and the proposed model.

Using the entropy estimates in Min et al. (2013), we establish the global existence and uniqueness of solutions to a fourth order equation related to image processing. Some numerical results on the Lena image are also presented to show the effectiveness of the equation for noise removal.

Section 2: Modeling; International audience

Part 9: Trust Software; International audience; As underlying infrastructure of cloud computing platform, datacenter is seriously underutilized, however, its operating costs is high. In this paper, we implement virtual machines placement algorithm in CloudSim using constraint programming approach. We first formulate the problem of virtual machines placement in virtualized datacenters as a variant of multi-dimensions bin packing problem, and then exploit constraint solver to solve this problem with the objective of minimizing number of physical machines that host virtual machines. Finally, we compare different virtual placement algorithms for evaluating constraint programming-based virtual machine placement algorithm including the built-in virtual machine placement algorithm in CloudSim and FFD algorithm. The experimental results show that constraint programming-based virtual machines placement algorithm can efficiently reduce the number of physical machines to achieve the goal of reducing datacenter operating costs and improving resource utilization.

International audience; A systematic study to model and characterize the band-modulation Z2-FET device is developed bringing light to the relevance of the carrier lifetime influence. This work provides guidelines to optimize the Z2-FETs for sharp switching, ESD protection, and 1T-DRAM applications. Lower carrier lifetime in the Z2-FET helps in attaining the sharp switch. We provide new insights into the correlation between generation/recombination, diffusion, electrostatic barriers and carrier lifetime.

International audience; The band-modulation and sharp-switching mechanisms in Z2-FET device operated as a capacitorless 1T-DRAM memory are reviewed. The main parameters that govern the memory performance are discussed based on detailed experiments and simulations. This 1T-DRAM memory does not suffer from super-coupling effect and can be integrated in sub-10 nm thick SOI films. It offers low leakage current, high current margin, long retention, low operating voltage especially for programming, and high speed. The Z2-FET is suitable for embedded memory applications.

International audience; The safety of high-speed trains has therefore become a key concern not only in the design process but also in their operation. Usually, plenty of testing jobs are performed through periodical maintenance to ensure the integrity of train structures, using offline nondestructive evaluation methods with relatively low cost-effectiveness. Based on the groupÕs efforts in the past ten years, a guided wave based damage detection and monitoring technique was developed to provide an online structural damage inspection approach, aiming to increase the safety of bogie structures and improve train operation efficiency. Miniaturized standard PZT sensors were developed to compose a pitch-catch based active sensor network for guided wave excitation and acquisition in the train bogie, and a compact system built with the proposed technique was implemented online to inquire information on structural health conditions. As a part of the conformance testing of ChinaÕs latest high-speed train model, experiments on a bogie frame of the train were carried out, especially when the train was running at a high speed, to validate the proposed technique and system, taking into account the complicated working states and the highly variable circumstances of the train, which are usually hard to be simulated in the lab. Several practical experiments were involved in the testing, including the survival rate of the sensor network, disturbance of mechanical vibration to signals, influences of actions of train (such as urgency brake), artificial damage detection, and so on. After running and testing for more than 1500 km, the experimental results from different conditions demonstrated high reliability and accuracy of the technique and the system.