Miracle-dz/UniFAR-FTUs huggingface dataset:
Simulation et modèles prédictifs pour les nanodispositifs avancés à canaux à base de matériaux alternatifs

Ce travail de these a pour but de contribuer au developpement d'outils numeriques pour la simulation de dispositifs avances a base de materiaux alternatifs au Si : l’InGaAs et le SiGe. C'est un travail de collaboration entre l'industrie (STMicroelectronics a Crolles) et des instituts de recherche (le CEA a Grenoble et l'IEMN a Lille). La modelisation de dispositifs MOSFET avances pour des applications de basse puissance est etudiee, grâce a des outils predictifs, mais efficaces et peu couteux numeriquement, qui peuvent etre compatibles avec un environnement industriel. L’etude porte sur differents aspects, tels que i) les proprietes electroniques des materiaux massifs et des nanostructures, avec des outils allant de la methode des liaisons fortes et des pseudo-potentiels empiriques, a la masse effective ; ii) les proprietes electrostatiques des capacites III-V ; iii) les proprietes de transport (mobilite effective a faible champ et vitesse de saturation) dans les films minces et les nanofils ; iv) la simulation de dispositifs conventionnels planaires FDSOI 14nm en regime lineaire et sature. Ce travail fait usage d'une large variete d'approches et de modeles differents. Des outils bases sur une approche physique sont developpes, permettant d'ameliorer la capacite predictive des modeles TCAD conventionnels, pour la modelisation des dispositifs nanoscopiques a courte longueur de grille et a base de materiaux SiGe ou InGaAs.
Build Your Own Ajax Web Applications

AJAX (Asynchronous JavaScript and XML) is a new approach for developing web applications. It essentially permits users to interact with a Webpage without forcing a slow & tedious reload of the entire page after every action. This means web applications become more responsive, easier to use, and more intuitive. Build Your Own Ajax Web Applications uses a step-by-step tutorial format that's so easy to follow, you'll be able to build sophisticated and intuitive Ajax web interfaces in no time! Read this book, and you'll: Get an overview of the basic technologies you'll need to use to build Ajax applications. Understand the XMLHttpRequest object, the core of Ajax applications. Build a cross-browser XMLHttpRequest wrapper that you can use in all of your Ajax projects. Build an Ajax application monitor that works in real time. Learn how to use Ajax without breaking older browsers or causing accessibility issues. Get your Ajax application working with screen readers. Use dynamic animations to improve usability. Build edit-in-place functionality. Create an Ajax search application that pulls data from Amazon, del.icio. us, and Google. Fix the "Back button" problem. Use JSON, YAML, and XML to communicate with the server. Build an Ajax drag 'n' drop chess game. And a whole lot more! Throughout the text, the author stresses usability, accessibility, and graceful degradation for older, less-capable web browsers.
Computational design of metadevices for heat flux manipulation considering the transient regime

Abstract The present work introduces the optimization-based approach for the design of metadevices to manipulate the heat flux in transient regime. It consists of solving a continuous, nonlinear, constrained, large-scale optimization problem where the objective function (to be minimized) is the error in accomplishing a given heat flux manipulation task along a transient heat conduction process. The response of the metadevice is modeled by using the finite element method, and its design is characterized by a set of parameters defining the material at all the finite elements in the device. These parameters are the design variables of the optimization problem, being chosen from an admissible design set in order to guarantee the feasibility of the optimal solution. As an example, this optimization-based approach is applied to the design of a heat flux shielding metadevice. Compared to a metadevice designed under the classical thermodynamics transformation approach and intuition, the current device performs the shielding task with considerably higher success. In order to highlight the versatility of the proposed optimization-based design method, this approach is also applied to the design of metadevices to satisfy multiple different simultaneous tasks, particularly shielding and cloaking.
Geometric and Topological Aspects of Soft & Active Matter

Topological and geometric ideas are now a mainstay of condensed matter physics, underlying much of our understanding of conventional materials in terms of defects and geometric frustration in ordered media, and protected edge states in topological insulators. In this thesis, I will argue that such an approach successfully identifies the relevant physics in metamaterials and living matter as well, even when traditional techniques fail. I begin with the problem of kirigami mechanics, i.e., designing a pattern of holes in a thin elastic sheet to engineer a specific mechanical response. Using an electrostatic analogy, I show that holes act as sources of geometric incompatibility, a feature that can fruitfully guide design principles for kirigami metamaterials. Next I consider nonequilibrium active matter composed of self-driven interacting units that exhibit large scale collective and emergent behaviour, as commonly seen in living systems. By focusing on active liquid crystals in two dimensions, with both polar and nematic orientational order, I show how broken time-reversal symmetry due to the active drive allows polar flocks on a curved surface to support topologically protected sound modes. In an active nematic, activity instead causes topological disclinations to become spontaneously motile, driving defect unbinding to organize novel phases of defect order and chaos. In all three cases, geometric and topological ideas enable the relevant degrees of freedom to be identified, allowing complex phenomena to be treated in a tractable fashion, with novel and surprising consequences along the way. Geometric and Topological Aspects of Soft & Active Matter
Unbiasedness of some generalized Adaptive Multilevel Splitting algorithms

We introduce a generalization of the Adaptive Multilevel Splitting algorithm in the discrete time dynamic setting, namely when it is applied to sample rare events associated with paths of Markov chains. By interpreting the algorithm as a sequential sampler in path space, we are able to build an estimator of the rare event probability (and of any nonnormalized quantity associated with this event) which is unbiased, whatever the choice of the importance function and the number of replicas. This has practical consequences on the use of this algorithm, which are illustrated through various numerical experiments.
Crosstalk analysis of uniform and nonuniform lossy microstrip‐coupled transmission lines

In this article, an analytical method is presented to precisely estimate the crosstalk of uniform and nonuniform microstrip‐coupled transmission lines (TLs) in frequency domain using modified transmission matrix. The obtained expression is quantitatively related in terms of the geometrical parameters of the coupled lines. A straightforward procedure is presented to obtain a closed form formula to accurately determine the crosstalk of a microstrip‐coupled line. For a nonuniform structure, the TL is divided into a few series of uniform sections with a specific modified transmission matrix. The total modified transmission matrix is determined by multiplying the modified transmission matrix of different sections and then the crosstalk can be calculated using the total modified transmission matrix. Several structures are considered to confirm the validity of the presented method. It is shown that the obtained results are in a good agreement with those obtained by simulation and measurement.
Effect of inlet sweepback angle on the cavitation performance of an inducer

ABSTRACT In order to study the effects of inlet sweepback angle on the cavitation performance of inducers based on the Reynolds N-S equation, RNG k-ε turbulent model, and Schnerr and Sauer cavitation model, a three-dimensional numerical calculation is employed to study the flow characteristics of a certain LNG pump. Laws of the variation of cavitation performance, head, and efficiency with the change of sweepback were studied. Numerical analysis of the eight inducer projects with a sweepback angle from 120° to 290° was carried out. The results show that the cavitation bubbles first appear at the suction surface near the inlet side. With the decrease of net positive suction head (NPSHa), the bubbles spread to the outlet side of the inducer and the pressure surface. Finally, they fill the entire channel. When the inducer sweepback angle increases from 120° to 270°, the NPSHr of the pump reduces gradually, that is to say that the anti-cavitation performance of the pump has been improved. However, the NPSHr of the pump increases gradually when the inducer sweepback angle increases from 270° to 290°. In other words, there is an optimal sweepback from 120° to 290°, and efficiency and head of pump tend to be stable near the optimal sweepback.
Additive phase-noise in frequency conversion in LLRF systems

This contribution focuses on phase-noise added during frequency conversion in low-level radio frequency (LLRF) control systems. The stability of beams' parameters in linear accelerators depends on the stability of amplitude and phase of the accelerating field. A LLRF control system regulates the electromagnetic field inside accelerating modules based on the input RF signals. Typically active mixers down-convert those signals, which are later sampled and digitized by ADCs. This field detection scheme necessitates synthesis of a heterodyne/local oscillator (LO) signal which is often generated using a passive mixer and a frequency divider. Additive close-to-carrier phase noise can be observed in the aforementioned circuits. The phase noise of a passive mixer's output signal is typically calculated using a small-signal model based on modulation theory. Experimental results indicate that the power level of the input signals has a nonlinear effect on phase noise beyond the noise floor. The frequency dividers' output phase noise was measured as a function of input power, input frequency, and division ratio. The influence of the LO signal power level on the active mixers' output signal phase noise was measured and two hypotheses were made. Further measurements of the AM-PM and PM-AM conversion were made to verify one of the hypotheses. The fidelity of the LO signal is partially determined by the phase noise of the IF signal.
Gibbs measures of an Ising model with competing interactions on the triangular chandelier-lattice

In this paper, we consider an Ising model with three competing interactions on a triangular chandelier-lattice (TCL). We describe the existence, uniqueness, and non-uniqueness of translation-invariant Gibbs measures associated with the Ising model. We obtain an explicit formula for Gibbs measures with a memory of length 2 satisfying consistency conditions. It is rigorously proved that the model exhibits phase transitions only for given values of the coupling constants. As a consequence of our approach, the dichotomy between alternative solutions of Hamiltonian models on TCLs is solved. Finally, two numerical examples are given to illustrate the usefulness and effectiveness of the proposed theoretical results.
Useful martingales for stochastic storage processes with Lévy input

We apply the general theory of stochastic integration to identify a martingale associated with a Lévy process modified by the addition of a secondary process of bounded variation on every finite interval. This martingale can be applied to queues and related stochastic storage models driven by a Lévy process. For example, we have applied this martingale to derive the (non-product-form) steady-state distribution of a two-node tandem storage network with Lévy input and deterministic linear fluid flow out of the nodes.
Light scattering by correlated disordered assemblies of nanoantennas

Optical nanoantennas are widely used to build absorbing metasurfaces with applications in photodetection, solar cells, and sensing. Most of the time, the nanoantennas are assembled as a periodic distribution, but there have been various works where disordered arrays are used, either to get rid of diffraction orders or due to a fabrication process that prevents any determined distribution. Here, we investigate both theoretically and experimentally the unavoidable scattering introduced by such disorders. By introducing a perturbation on the positions of 1D arrays of metal-insulator-metal (MIM) nanoantennas, the light is scattered rather than increasingly absorbed. The scattering occurs only in the plane of incidence and on a given spectral range. We show how this scattering can be manipulated from 0% to 55% of the incoming light.Optical nanoantennas are widely used to build absorbing metasurfaces with applications in photodetection, solar cells, and sensing. Most of the time, the nanoantennas are assembled as a periodic distribution, but there have been various works where disordered arrays are used, either to get rid of diffraction orders or due to a fabrication process that prevents any determined distribution. Here, we investigate both theoretically and experimentally the unavoidable scattering introduced by such disorders. By introducing a perturbation on the positions of 1D arrays of metal-insulator-metal (MIM) nanoantennas, the light is scattered rather than increasingly absorbed. The scattering occurs only in the plane of incidence and on a given spectral range. We show how this scattering can be manipulated from 0% to 55% of the incoming light.
Use of kerosene lamp containing synthetic pyrethroids to repel mosquitoes.

: An indigenous and appropriate method of personal protection was developed and tested in rural areas. It consists of an ordinary kerosene lamp made of tin with a regulator to adjust the wick. Different concentrations of esbiothrin, a synthetic pyrethroid, were mixed in kerosene and allowed to burn in living rooms and cattlesheds from dusk to dawn to observe hourly entry of mosquitoes. The tin lamp (100 ml capacity) without chimney provided the most efficient protection from mosquito bites. The protection varied from 84.2 +/- 8.2 to 97.8 +/- 2.8. Maximum protection was observed against An. culicifacies. Esbiothrin kerosene lamp (0.01%) lighted in living room provided 99.7% protection to exposed human baits seated at a distance of 1 m from the lamp. The technique is simple, cost-effective and does not require electricity and can be used both for illumination and repelling mosquitoes in remote and inaccesible areas.
Matched feeds for offset reflector antenna using circular microstrip patch antenna

This article presents two designs of matched feed for an offset fed reflector. Circular microstrip patch antennas are used in the proposed designs. Both the matched feeds achieve conjugate field matching by generating TM21 mode at an appropriate ratio to the fundamental TM11 mode. The first matched feed generates the required dual mode field distributions using a dual layer stacked patch antenna. The second matched feed is a novel design using centered circular array with the central element generating the required TM21 mode and the surrounding circular ring antenna elements operating in the TM11 mode. Both the designs are studied analytically using cavity model and are implemented in High frequency System Simulator (HFSS) and Computer Simulation Technology (CST). The matched feed designs are investigated for an offset reflector with the projected diameter, D = 50λ, focal length, F = 30λ and clearance height, H = 5λ operating at 20 GHz. The secondary field patterns of the offset reflector fed by the matched feeds are evaluated numerically using a MATLAB code based on geometrical optics technique and verified by HFSS‐PO results. Offset reflector performance such as cross‐polarization, −30 dB cross‐polar bandwidth, gain, and first side‐lobe level are investigated for the both matched feeds.
Adaptive tensegrity locomotion: Controlling a compliant icosahedron with symmetry-reduced reinforcement learning

Tensegrity robots, which are prototypical examples of hybrid soft–rigid robots, exhibit dynamical properties that provide ruggedness and adaptability. They also bring about, however, major challenges for locomotion control. Owing to high dimensionality and the complex evolution of contact states, data-driven approaches are appropriate for producing viable feedback policies for tensegrities. Guided policy search (GPS), a sample-efficient hybrid framework for optimization and reinforcement learning, has previously been applied to generate periodic, axis-constrained locomotion by an icosahedral tensegrity on flat ground. Varying environments and tasks, however, create a need for more adaptive and general locomotion control that actively utilizes an expanded space of robot states. This implies significantly higher needs in terms of sample data and setup effort. This work mitigates such requirements by proposing a new GPS -based reinforcement learning pipeline, which exploits the vehicle’s high degree of symmetry and appropriately learns contextual behaviors that are sustainable without periodicity. Newly achieved capabilities include axially unconstrained rolling, rough terrain traversal, and rough incline ascent. These tasks are evaluated for a small variety of key model parameters in simulation and tested on the NASA hardware prototype, SUPERball. Results confirm the utility of symmetry exploitation and the adaptability of the vehicle. They also shed light on numerous strengths and limitations of the GPS framework for policy design and transfer to real hybrid soft–rigid robots.
Temperature measurement using a microfiber knot ring encapsulated in PDMS

A microfiber knot ring with a temperature sensitivity of 183 pm °C−1 has been proposed and experimentally demonstrated. To further improve its stability and sensitivity, the polydimethylsiloxane (PDMS) film was used to encapsulate it to be a slice probe. The temperature sensitivity was increased for more than 9 folds with a good stability and repeatability. The contribution ratios of thermal-optic coefficient and thermal-expansion coefficient of silica and PDMS were analyzed and discussed. The high sensitivity of 1.67 nm °C−1 and miniature slice structure enables its application for precisely monitoring the temperature fluctuation in some special occasions.
Solving Current Limitations of Deep Learning Based Approaches for Plant Disease Detection

Plant diseases cause great damage in agriculture, resulting in significant yield losses. The recent expansion of deep learning methods has found its application in plant disease detection, offering a robust tool with highly accurate results. The current limitations and shortcomings of existing plant disease detection models are presented and discussed in this paper. Furthermore, a new dataset containing 79,265 images was introduced with the aim to become the largest dataset containing leaf images. Images were taken in various weather conditions, at different angles, and daylight hours with an inconsistent background mimicking practical situations. Two approaches were used to augment the number of images in the dataset: traditional augmentation methods and state-of-the-art style generative adversarial networks. Several experiments were conducted to test the impact of training in a controlled environment and usage in real-life situations to accurately identify plant diseases in a complex background and in various conditions including the detection of multiple diseases in a single leaf. Finally, a novel two-stage architecture of a neural network was proposed for plant disease classification focused on a real environment. The trained model achieved an accuracy of 93.67%.
Quantum information processing in semiconductor quantum dots using single and multi-spin qubits

The idea of a quantum computer, a device capable of processing information using quantum bits (qubit) instead of classical bits that outperforms classical computer in terms of computation speed, is still science fiction. However, recent advances in quantum information processing showed that this fiction may come true faster than anticipated. A promising platform for the physical realization of a qubit are spin qubits where the information is encoded in the quantum mechanical spin of an electron confined in a semiconductor quantum dot. There are a variety of different implementations how the logical qubit is physically encoded, the use of a single electron spin or the use of the spins of multi electrons. This thesis focuses on the implementation of the spin-12 qubit using the spin of a single electron in a single quantum dot, the exchangeonly (EO) qubit using three electron spins distributed in three quantum dots, and the novel quadrupolar exchange-only (QUEX) qubit using four electron spins distributed in three quantum dots. In this thesis we investigate several theoretical aspects of the physical implementation of the aforementioned qubit encodings. Since all three qubit encodings are allelectric controlled these implementations suffer decoherence, the loss of information, from electric fluctuations of the environment commonly called charge noise. Typically, the use of more quantum dots increases the decoherence due to charge noise while it decreases the decoherence due to magnetic noise. The first main aspect investigated in this thesis is the protection of the quantum information encoded in the different qubit implementations against charge noise. Special attention is paid to the multi-electron spin implementations where high-symmetry points of operation are discovered which are less sensitive to the charge noise. Protection against charge noise is even better by increasing the number of electrons while keeping the number of quantum dots making the QUEX qubit superior to the EO qubit. So far the main direction in this thesis is the reduction of the qubit sensitivity to electric fluctuations. However, coherent electromagnetic fields in form of microwaves
PERFORMANCE EVALUATION OF A STAR-SHAPED PATCH ANTENNA ON POLYIMIDE FILM UNDER VARIOUS BENDING CONDITIONS

—This paper proposes a prototype of a ﬂexible antenna which utilizes a star patch design. The work seeks feasibility of the star patch antenna to maintain its characteristic when it is bending on a curvy structure. The patch antenna is fabricated on a 0.8 mm thickness, h of polyimide ﬁlm with a dielectric constant, ε r of 3.4. The simulation result in Computer Simulation Technology Microwave Studio (CST MWS R (cid:2) ) software shows that the antenna provides a − 10 dB bandwidth of 24.9% at 2.45 GHz with a minimum reﬂection coeﬃcient, S 11 of − 26 . 67 dB in ﬂat condition. The stability in its performance has been noticed in which the shift in the resonant frequency is less than 2% when the structure is bending on a curvy surface with a radius of 90 mm. The measured results in terms of reﬂection coeﬃcient, bandwidth, radiation pattern, and gain demonstrate a good agreement with the simulated results.