Letteratura scientifica selezionata sul tema "Modulation angulaire"
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Articoli di riviste sul tema "Modulation angulaire":
1
Bertho, A., M. Dos Santos, A. François e F. Milliat. "Histoire de la prise en charge des cancers bronchopulmonaires non à petites cellules de stade précoce : de la chirurgie à la radiothérapie stéréotaxique". Radioprotection 55, n. 3 (20 maggio 2020): 165–72. http://dx.doi.org/10.1051/radiopro/2020050.
Abstract (sommario):
Avant le début du XXe siècle, le cancer bronchopulmonaire était une maladie rare. Aujourd’hui, c’est le quatrième cancer le plus fréquent en France et concerne, chaque année, près de 50 000 patients. Si à travers l’histoire, la pierre angulaire de la prise en charge thérapeutique du cancer bronchopulmonaire reste la chirurgie, la radiothérapie en est un des piliers, notamment chez les patients à haut risque chirurgical. La radiothérapie est apparue quelques mois après la découverte des rayons X en 1896 et, rapidement, des protocoles standardisés ont été mis au point par les premiers radiobiologistes. Ces protocoles sont ceux que nous connaissons encore aujourd’hui : 2 Gy par fraction et 5 fractions par semaine sur une durée totale de 5 à 8 semaines. Si les protocoles ont peu changé en un siècle, la technique et la balistique ont connu de grandes avancées. Ces améliorations ont mené à un bouleversement profond des protocoles. Les améliorations techniques de délivrance de dose, par l’optimisation de l’imagerie, de la précision du positionnement des patients et dans la modulation de la géométrie des faisceaux ont conduit au développement de la radiothérapie en conditions stéréotaxiques ou radiothérapie stéréotaxique. Aujourd’hui, la radiothérapie stéréotaxique est utilisée pour la prise en charge des tumeurs bronchopulmonaires de stade précoce comme alternative à la chirurgie.
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Wang, Huan, Jiajun Linghu, Xuezhi Wang, Qiyi Zhao e Hao Shen. "Angular-Dependent THz Modulator with Hybrid Metal-Graphene Metastructures". Nanomaterials 13, n. 13 (23 giugno 2023): 1914. http://dx.doi.org/10.3390/nano13131914.
Abstract (sommario):
The coupling effects of surface plasmon resonance (SPR) from metamaterials induce variation in both the frequency and intensity of plasmonic modes. Here, we report an angular-dependent THz modulator with hybrid metal–graphene metastructures. The metastructures composed of the period gold split-rod arrays on top of a monolayer graphene, which show redshift modulation in the THz region with an increasing incident angle due to the strong out-of-plane magnetic flux introduced by the clockwise circular current at the oblique incidence. By utilizing graphene-based actively tunable conductor with ion-gel electrical gating, the THz transmission can be significantly modified. The modulation depth of the hybrid metal–graphene metastructure modulator can reach ~37.6% at 0.62 THz with a gate voltage of −3 V. The theoretical modeling of transmitted dependency on frequency and incident angle is demonstrated at different Fermi energies, which fits well with the experimental results. This hybrid device can offer a useful method for THz applications (such as angle sensors or angular-resolved spectroscopy), where angle-dependent modulation is needed.
3
Liu, Peijun, Yanan Fu, Xi Xie, Changjun Min, Yuquan Zhang e Xiaocong Yuan. "High-efficiency monolayer metallic metasurface for modulation of orbital angular momentum". Chinese Optics Letters 20, n. 12 (2022): 123601. http://dx.doi.org/10.3788/col202220.123601.
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Huang Xianming, 黄先明, 王飞 Wang Fei, 陆宝乐 Lu Baole e 白晋涛 Bai Jintao. "基于轨道角动量交换实现巨克尔非线性效应调控". Acta Optica Sinica 42, n. 22 (2022): 2219002. http://dx.doi.org/10.3788/aos202242.2219002.
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Wang, Jian, Jun Liu, Shuhui Li, Yifan Zhao, Jing Du e Long Zhu. "Orbital angular momentum and beyond in free-space optical communications". Nanophotonics 11, n. 4 (14 dicembre 2021): 645–80. http://dx.doi.org/10.1515/nanoph-2021-0527.
Abstract (sommario):
Abstract Orbital angular momentum (OAM), which describes tailoring the spatial physical dimension of light waves into a helical phase structure, has given rise to many applications in optical manipulation, microscopy, imaging, metrology, sensing, quantum science, and optical communications. Light beams carrying OAM feature two distinct characteristics, i.e., inherent orthogonality and unbounded states in principle, which are suitable for capacity scaling of optical communications. In this paper, we give an overview of OAM and beyond in free-space optical communications. The fundamentals of OAM, concept of optical communications using OAM, OAM modulation (OAM modulation based on spatial light modulator, high-speed OAM modulation, spatial array modulation), OAM multiplexing (spectrally efficient, high capacity, long distance), OAM multicasting (adaptive multicasting, N-dimensional multicasting), OAM communications in turbulence (adaptive optics, digital signal processing, auto-alignment system), structured light communications beyond OAM (Bessel beams, Airy beams, vector beams), diverse and robust communications using OAM and beyond (multiple scenes, turbulence-resilient communications, intelligent communications) are comprehensively reviewed. The prospects and challenges of optical communications using OAM and beyond are also discussed at the end. In the future, there will be more opportunities in exploiting extensive advanced applications from OAM beams to more general structured light.
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Liu, Jun, Shuang Zheng, Shi Chen, Long Zhu, Shimao Li, Shengqian Gao, Heyun Tan, Xinlun Cai e Jian Wang. "High-speed spatial light modulation based on photon dimension mapping assisted by an integrated mode multiplexer". Applied Physics Letters 120, n. 13 (28 marzo 2022): 131103. http://dx.doi.org/10.1063/5.0076652.
Abstract (sommario):
Photon dimension mapping provides an efficient way to learn from each other's strengths to offset their own weaknesses in a variety of applications. By mapping the conventional amplitude modulation to spatial mode modulation and employing an integrated orbital angular momentum (OAM) mode multiplexer, we present an integrated approach to break the spatial light modulation speed limit and implement the high-speed silicon-chip-assisted OAM encoding information transfer. The silicon chip is formed by a multi-mode micro-ring resonator with angular grating embedded in the inner wall and two bus waveguides with different widths for OAM mode multiplexing. Using the fabricated silicon-based OAM mode multiplexer (OAM+1 and OAM-14), we demonstrate 15-Gbit/s amplitude-to-OAM modulation mapping in the experiment, which is far beyond the achievable low-speed OAM encoding information transfer with a conventional spatial light modulator (SLM). The observed optical signal-to-noise ratio (OSNR) penalties at a bit-error rate (BER) of 2 × 10−3 are about 1.0 dB, and the OSNR penalty is improved by about 1.4 dB with the balanced detection. The demonstrations with favorable performance may open up added opportunities in more spatial-mode-enabled applications by photon dimension mapping with silicon chips.
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Buzzelli, A., P. de Bernardis, S. Masi, N. Vittorio e G. de Gasperis. "Optimal strategy for polarization modulation in the LSPE-SWIPE experiment". Astronomy & Astrophysics 609 (gennaio 2018): A52. http://dx.doi.org/10.1051/0004-6361/201730754.
Abstract (sommario):
Context. Cosmic microwave background (CMB) B-mode experiments are required to control systematic effects with an unprecedented level of accuracy. Polarization modulation by a half wave plate (HWP) is a powerful technique able to mitigate a large number of the instrumental systematics. Aims. Our goal is to optimize the polarization modulation strategy of the upcoming LSPE-SWIPE balloon-borne experiment, devoted to the accurate measurement of CMB polarization at large angular scales. Methods. We departed from the nominal LSPE-SWIPE modulation strategy (HWP stepped every 60 s with a telescope scanning at around 12 deg/s) and performed a thorough investigation of a wide range of possible HWP schemes (either in stepped or continuously spinning mode and at different azimuth telescope scan-speeds) in the frequency, map and angular power spectrum domain. In addition, we probed the effect of high-pass and band-pass filters of the data stream and explored the HWP response in the minimal case of one detector for one operation day (critical for the single-detector calibration process). We finally tested the modulation performance against typical HWP-induced systematics. Results. Our analysis shows that some stepped HWP schemes, either slowly rotating or combined with slow telescope modulations, represent poor choices. Moreover, our results point out that the nominal configuration may not be the most convenient choice. While a large class of spinning designs provides comparable results in terms of pixel angle coverage, map-making residuals and BB power spectrum standard deviations with respect to the nominal strategy, we find that some specific configurations (e.g., a rapidly spinning HWP with a slow gondola modulation) allow a more efficient polarization recovery in more general real-case situations. Conclusions. Although our simulations are specific to the LSPE-SWIPE mission, the general outcomes of our analysis can be easily generalized to other CMB polarization experiments.
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Belousov, Igor, Veniamin Samoseiko e Alecsandr Saushev. "Assessment of filtering properties of asynchronous electric drive with pulse width modulation". E3S Web of Conferences 363 (2022): 01025. http://dx.doi.org/10.1051/e3sconf/202236301025.
Abstract (sommario):
The process of pulse-width modulation in the converter-motor system is considered. It is noted that the main task of pulse width modulation of voltage formed by the electronic key converter in the converter-motor system is to reduce current pulsations during the modulation period. It is established, that the dynamic process of current change in the electric machine during the period of pulse-width modulation can be approximated by R, L filter. It is shown, that the most important task of pulse-width modulation is minimization of modulation error by current in electric motor. The analysis of possible criteria of estimation of modulation process quality in control systems of electric drive is carried out. It is noted that as a criterion of optimality to assess the quality of modulation in the converter-electromotor system, it is advisable to use the integral quadratic criterion of relative error, called the local variance of the current, as well as the average value of the local variance of the current at the period of the modulating function, called the integral variance of current. The process of estimating the filtering ability of electric machines as part of the electric drive is considered. A system of basic values based on nominal values of electric motor stator voltage, its nominal angular speed and nominal stator current has been selected. The index of filtering properties of the load considering introduction of basic values has been proposed. The equations of an asynchronous electric machine with constant coefficients in the complex form of writing are given. The dependency of the real part of roots of the characteristic equation for an asynchronous machine as a function of angular speed of the rotor rotation is constructed. An analytical expression for the estimation of the filtering properties of asynchronous machines is obtained. The comparison of different types of electric machines according to this parameter is made.
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Zhang, Chenming, Jie Li, Xiaoqiao Yuan, Xi Zhang, Xiaokai Wei, Kaiqiang Feng, Chenjun Hu, Debiao Zhang e Yubing Jiao. "Optimal Rotational Angular Velocity Determination Method Based on Compound Rotary Semi-Strapdown Inertial Navigation System". Sensors 22, n. 12 (17 giugno 2022): 4583. http://dx.doi.org/10.3390/s22124583.
Abstract (sommario):
Single-axis rotation modulation (SRM) still accumulates errors in the roll axis direction, which leads to the navigation accuracy not meeting the requirements of guided missiles. Compound rotation modulation (CRM) superimposes one-dimensional rotation on the basis of SRM, so that the error of the projectile in the direction of the roll axis is also modulated. However, the error suppression effect of CRM is not only affected by the error of the IMU itself, but also related to the modulation angular velocity. In order to improve the accuracy of rotary semi-strapdown inertial navigation system (RSSINS), this paper proposes an optimal rotation angular velocity determination method. Firstly, the residual error in CRM scheme is analyzed; then, the relationship between the incomplete modulation error and the modulation angular velocity in CRM is discussed; finally, a method for determining the optimal modulation angular velocity is proposed (K-value method). The analysis of the results shows that the navigation accuracy of the guided projectile is effectively improved with the rotation scheme set at the modulation angular velocity determined by the K-value method.
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Kushiro, Keisuke, Mingjia Dai, Mikhail Kunin, Sergei B. Yakushin, Bernard Cohen e Theodore Raphan. "Compensatory and Orienting Eye Movements Induced By Off-Vertical Axis Rotation (OVAR) in Monkeys". Journal of Neurophysiology 88, n. 5 (1 novembre 2002): 2445–62. http://dx.doi.org/10.1152/jn.00197.222.
Abstract (sommario):
Nystagmus induced by off-vertical axis rotation (OVAR) about a head yaw axis is composed of a yaw bias velocity and modulations in eye position and velocity as the head changes orientation relative to gravity. The bias velocity is dependent on the tilt of the rotational axis relative to gravity and angular head velocity. For axis tilts <15°, bias velocities increased monotonically with increases in the magnitude of the projected gravity vector onto the horizontal plane of the head. For tilts of 15–90°, bias velocity was independent of tilt angle, increasing linearly as a function of head velocity with gains of 0.7–0.8, up to the saturation level of velocity storage. Asymmetries in OVAR bias velocity and asymmetries in the dominant time constant of the angular vestibuloocular reflex (aVOR) covaried and both were reduced by administration of baclofen, a GABAB agonist. Modulations in pitch and roll eye positions were in phase with nose-down and side-down head positions, respectively. Changes in roll eye position were produced mainly by slow movements, whereas vertical eye position changes were characterized by slow eye movements and saccades. Oscillations in vertical and roll eye velocities led their respective position changes by ≈90°, close to an ideal differentiation, suggesting that these modulations were due to activation of the orienting component of the linear vestibuloocular reflex (lVOR). The beating field of the horizontal nystagmus shifted the eyes 6.3°/ g toward gravity in side down position, similar to the deviations observed during static roll tilt (7.0°/ g). This demonstrates that the eyes also orient to gravity in yaw. Phases of horizontal eye velocity clustered ∼180° relative to the modulation in beating field and were not simply differentiations of changes in eye position. Contributions of orientating and compensatory components of the lVOR to the modulation of eye position and velocity were modeled using three components: a novel direct otolith-oculomotor orientation, orientation-based velocity modulation, and changes in velocity storage time constants with head position re gravity. Time constants were obtained from optokinetic after-nystagmus, a direct representation of velocity storage. When the orienting lVOR was combined with models of the compensatory lVOR and velocity estimator from sequential otolith activation to generate the bias component, the model accurately predicted eye position and velocity in three dimensions. These data support the postulates that OVAR generates compensatory eye velocity through activation of velocity storage and that oscillatory components arise predominantly through lVOR orientation mechanisms.
Tesi sul tema "Modulation angulaire":
1
Javahiraly, Nicolas. "Méthode d'analyse optique du module de rigidité. Application à un capteurs photonique de position angulaire et de couple à modulation d'amplitude et de polarisation". Université Louis Pasteur (Strasbourg) (1971-2008), 2002. http://www.theses.fr/2002STR13092.
Abstract (sommario):
Nous présentons le principe, le concept et le développement technologique de deux types de capteurs : un capteur de position angulaire à fibre optique basé sur les phénomènes de couplage de modes, et un capteur de couple photonique basé sur la modulation de la polarisation. Après une présentation de l'état de l'art en matière de mesure du couple et de position angulaire, nous analysons la propagation de la lumière dans les fibres optiques en considérant ses aspects électromagnétiques et opto-géométriques, applicables aux capteurs à modulation de polarisation en développant le phénomène de polarisation et aux capteurs à modulation d'amplitude en développant le couplage de modes. Nous avons réalisé l'étude théorique et expérimentale des réponses du capteur de couple et position angulaire en fonction de la nature et de la géométrie du matériau le constituant. Nous obtenons expérimentalement pour le capteur de couple, des sensibilités comprises entre 2,233. 10-3 et 1,067 ʿ/N. M et des raideurs comprises entre 5,91 et 448,01 N. M/ʿ suivant la nature et la géométrie du matériau utilisé. La comparaison entre les valeurs théoriques et expérimentales donne un écart maximum de 1,68 à 3,4%. Nous avons testé la répétabilité du capteur de couple présentant un arbre creux en Acier de section carrée, de longueur 150mm. Un écart maximum de ±2,57%a été obtenu. L'influence des variations en Température pour DT=130ʿC donne une augmentation de 7% par rapport à la théorie. Enfin, en utilisant un dispositif expérimental pour obtenir un signal de référence, nous avons obtenu un écart maximum de la sensibilité et de la raideur de 0,59% par rapport à la théorie. Par conséquent, nous minimisons les fluctuations de la source avec le dispositif de référenceWe propose the principle, the concept and the technological development of two types of sensors: on fiber optic angular position sensor based on the modes coupling and a photonic torque sensor based on the polarization modulation. After a state of art concerning the torque and the angular sensor, we analyze the light propagation in the fiber optic in an electromagnetic and opto-geometrical way applicable to the sensor. We have analyzed the theoretical and the experimental responses of the sensors as a function of the material nature and its geometry. We obtained experimentally, for the torque sensor, a sensitivity between 2,233. 10-3 and 1,067 ʿ/N. M and a stiffness between 5,91 and 448,01 N. M/ʿ. The comparison between the theoretical and the experimental results gives a maximum difference between 1,68% and 3,4%. We have tested the Temperature fluctuations influence for DT=130ʿC and the results gave 7% of difference with the theory. By using an experimental set up to obtain a reference signal, we obtained a 0,59% maximum difference for the sensitivity and the stiffness. So, we minimize the source fluctuations with this reference set up
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Keller, Niels. "Étude angulaire du deuxième champ critique dans les supraconducteurs à fermions lourds UPt3, URu2Si2 et CeCu2Si2". Université Joseph Fourier (Grenoble ; 1971-2015), 1994. http://www.theses.fr/1994GRE10119.
Abstract (sommario):
Cette these est consacree a l'etude experimentale du deuxieme champ critique des supraconducteurs a fermions lourds upt#3, uru#2si#2 et cecu#2si#2. La supraconductivite de ces composes, qui est presumee de nature non conventionnelle, est supposee influencer fortement la dependance angulaire du deuxieme champ critique h#c#2 dans le plan basal du compose hexagonal upt#3 et des composes tetragonaux uru#2si#2 et cecu#2si#2. Ainsi, la mesure de la variation angulaire de h#c#2 peut aider a distinguer le type de parametre d'ordre supraconducteur. La variation angulaire de h#c#2 dans le plan basal et le diagramme de phase anisotrope h#c#2(t) ont ete determines pour les trois composes au moyen des mesures de resistivite sous champ magnetique (orientale dans toutes les directions spatiales) et a tres basses temperatures. En ce qui concerne le compose upt#3, une contribution de la supraconductivite de surface liee a la geometrie a ete mise en evidence, dans les mesures de resistivite pour des whiskers. L'etude de nouveaux monocristaux d'upt#3 de bonne qualite, dont les transitions supraconductrices mesurees par chaleur specifique et par resistivite coincident, a permis de detecter pour la premiere fois une modulation intrinseque d'ordre six (periodicite de 60) du deuxieme champ critique dans le plan hexagonal. Cette modulation change le signe au point tetracritique du diagramme de phase. Ce resultat est une evidence directe que le parametre d'ordre supraconducteur change entre les differentes phases supraconductrices. Le deuxieme champ critique h#c#2, mesure dans le plan tetragonal des composes uru#2si#2 et cecu#2si#2, presente une modulation de h#c#2 de symetrie quatre qui n'avait jamais ete observee jusqu'a present. A premiere vue, une interpretation selon un parametre d'ordre de type d se propose, mais des efforts supplementaires sont necessaires afin d'avoir la certitude que les effets de surface ne sont pas presents dans ces faibles modulations du h#c#2
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Fourati, Aroua. "Modélisation électro-magnéto-mécanique d'une machine asynchrone sous approche angulaire : Application au diagnostic des défauts de roulements en régime non stationnaire". Thesis, Lyon, 2017. http://www.theses.fr/2017LYSEI078.
Abstract (sommario):
Dans une machine à induction, le diagnostic de défauts par analyse du signal du courant électrique nécessite la connaissance du comportement dynamique de la machine. En plus des sources externes d'excitation, le comportement du moteur est gouverné par un ensemble de phénomènes périodiques liés sa géométrie angulairement périodique et couplés par leur caractère multiphysique. En présence d’un défaut de roulement, les grandeurs mesurables présenteront des composantes à sa fréquence caractéristique combinée aux fréquences caractéristiques du moteur. La compréhension des interactions, en particulier de modulation, passe par la mise en place de modèles numériques qui représentent les manifestations des phénomènes couplés. Ce travail de thèse propose donc un modèle électro-magnéto-mécanique d'une machine à induction à cage d'écureuil couplé à un modèle de palier à roulement à billes dans un cadre original d'écriture appelé "Approches Angulaires". En conservant dans la modélisation la relation "Angle-Temps" il est possible d'étendre aisèment la modélisation aux conditions de fonctionnement non-stationnaires et d'introduire un couplage fort entre les modèles mécanique et électromagnétique. Ainsi, on montre que la vitesse angulaire instantanée est la grandeur qui assure la transmission du défaut mécanique localisé aux grandeurs électriques. Le modèle proposé offre ainsi un décryptage des phénomènes de modulation présents sur la voie de transfert et décrits par les couplages de comportements dynamiques cycliques (réseau de perméances, chargement des éléments roulants,...) et/ou périodiques (résonances de structure, résonance électriques, ...). Ces travaux ouvrent la voie à une meilleure compréhension du comportement couplé multiphysique d'une machine électrique pour mieux spécifier les outils de surveillance à mettre en œuvre. Les futurs développements peuvent maintenant s'orienter ver une complexification des modèles ou l'exploitation de comportements dynamiques fins en régime non-stationnaireIn an induction machine, the diagnosis of defects by analysis of the electrical current signal requires knowledge of the dynamic behavior of the machine. In addition to external excitation sources, the behavior of the motor is governed by a set of periodic phenomena related to its angularly periodic geometry and coupled by their multiphysical character. In the presence of a bearing defect, measurable quantities will have components at its characteristic frequency combined with the characteristic frequencies of the engine. The understanding of interactions, in particular modulation, requires the implementation of numerical models that represent the manifestations of coupled phenomena. This thesis work proposes an electro-magneto-mechanical model of a squirrel-cage induction machine coupled to a rolling bearing model in an original writing frame called "Angular Approaches". By keeping the "Angle-Time" relation in modeling, it is possible to easily extend the modeling to non-stationary operating conditions and to introduce a strong coupling between the mechanical and electromagnetic models. Thus, it is shown that the instantaneous angular speed is the quantity which ensures the transmission of the localized mechanical defect to the electrical quantities. The proposed model thus offers a decryption of the modulation phenomena present on the transfer path and described by the couplings of cyclic dynamic behaviors (permeance network, loading of the rolling elements, etc.) and / or periodic (structural resonances, electrical resonance, etc.). This work opens the way for a better understanding of the multiphysical coupled behaviors of an electrical machine to better specify the monitoring tools to be used. Further developments can now be directed to a complexity of models or to the exploitation of fine dynamic behaviors in a non-steady operating conditions
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Ernould, Clément. "Développement et application d’une méthode à haute résolution angulaire pour la mesure des gradients d’orientation et des déformations élastiques par microscopie électronique à balayage". Electronic Thesis or Diss., Université de Lorraine, 2020. http://www.theses.fr/2020LORR0225.
Abstract (sommario):
La compréhension des mécanismes de déformation dans les matériaux cristallins passe par la caractérisation fine des microstructures. Dans le cadre de la microscopie électronique à balayage, la mesure précise des gradients d’orientation et des déformations élastiques du cristal est l’objectif des méthodes dites à haute résolution angulaire. Pour cela, elles emploient des techniques de corrélation d’images numériques afin de recaler les clichés de diffraction électronique. Cette thèse propose une méthode de recalage originale. Le champ de déplacement à l’échelle du scintillateur est décrit par une homographie linéaire. Il s’agit d’une transformation géométrique largement utilisée en vision par ordinateur pour modéliser les projections. L’homographie entre deux clichés est mesurée à partir d’une grande et unique région d’intérêt en utilisant un algorithme de Gauss-Newton par composition inverse numériquement efficace. Une correction des distorsions optiques causées par les lentilles de la caméra lui est intégrée et sa convergence est assurée par un pré-recalage des clichés. Ce dernier repose sur des algorithmes de corrélation croisée globale basés sur les transformées de Fourier-Mellin et de Fourier. Il permet de rendre compte des rotations allant jusqu’à une dizaine de degrés avec une précision comprise typiquement entre 0,1 et 0,5°. La détermination de l’homographie est indépendante de la géométrie de projection. Cette dernière n’est considérée qu’à l’issue du recalage pour déduire analytiquement les rotations et les déformations élastiques. La méthode est validée numériquement sur des clichés simulés distordus optiquement, désorientés jusqu’à 14° et présentant des déformations élastiques équivalentes jusqu’à 5×10⁻². Cette étude montre que la mesure précise de déformations élastiques comprises entre 1×10⁻⁴ et 2×10⁻³ nécessite de corriger la distorsion optique radiale, même lorsque la désorientation est faible. Finalement, la méthode est appliquée à des clichés acquis par diffraction des électrons rétrodiffusés (EBSD) et en transmission en utilisant la nouvelle configuration TKD on-axis (transmission Kikuchi diffraction). Des métaux polycristallins déformés plastiquement ainsi que des semi-conducteurs sont caractérisés. La méthode retranscrit des détails fins de la microstructure d’un acier martensitique trempé et revenu et d’un acier sans interstitiels déformé de 15% en traction, malgré la détérioration du contraste de diffraction induit par la déformation plastique. Les structures de déformation sont également analysées dans de l’aluminium nanostructuré obtenu par déformation plastique sévère grâce au couplage de la méthode de recalage et de la configuration TKD on-axis. Ce couplage permet d’atteindre simultanément une haute résolution spatiale (3 à 10 nm) et une haute résolution angulaire (0,01 à 0,05°). Des cartes de déformation élastiques sont obtenues à l’échelle de quelques nanomètres dans une lame mince de SiGe et les densités de dislocations dans un monocristal de GaN sont déterminées avec une résolution voisine de 2,5×10⁻³ µm⁻¹ (soit 8×10¹² m⁻²)Understanding the deformation mechanisms in crystalline materials requires a fine characterization of microstructures. The precise measurement of lattice rotations and elastic strains in the scanning electron microscope is the aim of the so-called high-angular resolution methods. For this purpose, digital image correlation techniques are used in order to register electron diffraction patterns. In this thesis, an original registration approach is proposed. The displacement field across the whole scintillator is modelled by a linear homography. Such a shape function is often met is the field of computer vision to describe projective transformations. The homography between two patterns is measured from a single and large region of interest using a numerically efficient inverse-compositional Gauss-Newton algorithm. It integrates a correction of optical distortions caused by camera lenses and its convergence is ensured by a pre-alignment step of the patterns. The latter relies on global cross-correlation algorithms based on Fourier-Mellin and Fourier transforms. It fairly accounts for rotations up to approximately ten degrees with an accuracy typically between 0.1 and 0.5°. The homography is measured independently from the projection geometry, which is only considered afterwards to analytically deduce the rotations and elastic strains. The proposed method is validated numerically from simulated and optically distorted patterns showing disorientations up to 14° in the presence of elastic strains up to 5×10⁻². The accurate measurement of elastic strains between 1×10⁻⁴ and 2×10⁻³ requires a correction of radial distortion effects, even when the disorientation angle is small. Finally, the method is applied to patterns acquired by means of electron backscatter diffraction (EBSD) and in transmission using the new on-axis transmission Kikuchi diffraction (TKD) configuration. Plastically deformed polycrystalline metals as well as semiconductors are characterized. The method highlights fine details of the microstructure of a quenched and tempered martensitic steel and of an interstitial free steel deformed by 15% in tension, although plastic deformation deteriorates the diffraction contrast. The deformation structures in a nanostructured aluminium obtained by severe plastic deformation are also analysed by coupling the image registration method to the on-axis TKD configuration. This coupling allows a high spatial resolution (3 to 10 nm) and a high angular resolution (0.01 to 0.05°) to be reached simultaneously. Elastic strain maps are obtained at the nanoscale in a SiGe thin foil. The geometrically necessary dislocation densities in a GaN single crystal are mapped with a resolution of about 2.5×10⁻³ µm⁻¹ (i.e. 8×10¹² m⁻²)
5
Klein, Maren. "Modulation phonologischer und semantischer Prozesse im Sprachnetzwerk: Eine kombinierte TMS-fMRT-Studie". Doctoral thesis, Universitätsbibliothek Leipzig, 2015. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-165709.
Abstract (sommario):
Insbesondere bildgebende Verfahren wie die funktionelle Magnetresonanztomografie (fMRT), haben innerhalb der letzten Jahre verdeutlicht, dass verschiedene Sprachkomponenten in weit verzweigten kortikalen Netzwerken im menschlichen Gehirn repräsentiert sind. Die in dieser Arbeit durchgeführte Studie kombinierte transkranielle Magnetstimulation (TMS) und fMRT mit dem Ziel phonologische und semantische Sprachnetzwerke detaillierter zu charakterisieren. Bisherige Studien identifizierten u. a. den linken Gyrus supramarginalis (SMG) und posterioren Anteil des Gyrus frontalis inferior (pIFG) als Kernregionen der phonologischen Entscheidungsaufgabe. Semantische Entscheidungsaufgaben wurden dahingegen u. a. mit dem linken Gyrus Angularis (ANG) und dem anterioren Anteil des Gyrus frontalis inferior (aIFG) in Verbindung gebracht.
In der vorliegenden Arbeit wurde ein Laborexperiment an 17 gesunden, rechtshändigen und deutschsprachigen Probanden in zwei Sitzungen durchgeführt. Mithilfe eines hemmenden TMS Protokolls, der „continuous Theta Burst Stimulation“ (cTBS) sollte die kortikale Erregbarkeit über den Stimulationszeitraum hinaus reversibel moduliert werden. Eine neuronavigierte cTBS wurde entweder über dem linken SMG oder dem linken ANG appliziert. Der cTBS folgte, direkt im Anschluss, eine ereigniskorrelierte fMRT Untersuchung, während derer die Probanden auditiv präsentierte semantische und phonologische (Einzel ) Wortentscheidungsaufgaben bearbeiteten. Mit der fMRT sollten Veränderungen kortikaler Aktivierungsmuster durch die konditionierende TMS während der Bearbeitung der Aufgaben abgebildet werden.
Die Ergebnisse der Studie tragen zum Verständnis der Wirkungsweise der cTBS über nicht motorischen Kortexarealen bei. Die Stimulation führte zu einer signifikanten Abnahme des „blood oxygenation level dependent“ (BOLD) Kontrasts am Stimulationsort. Weiterhin zeigten die Ergebnisse, dass die cTBS nicht nur am Ort der Stimulation zu einer Änderung der BOLD Kontrasts führt, sondern ein gesamtes Netzwerk spezifisch zu modulieren scheint. Eine cTBS über dem linken SMG führt u. a. zu einer verminderten BOLD Antwort im linken pIFG. Die Stimulation des linken ANG resultierte u. a. in einer erniedrigten BOLD Reaktion des aIFG. Eine Aufgabenspezifität nach Stimulation des SMG bzw. ANG wurde jedoch nicht evident. Dennoch unterstützen die Ergebnisse die Annahme, dass mögliche Verhaltenseffekte nach einer cTBS nicht zwingend auf den Ort der Stimulation zurückgeführt werden können. Weiterhin verdeutlichen die Stimulationseffekte, dass der SMG und der ANG in zwei unterschiedliche Netzwerke eingebunden sind.
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Vitullo, Dashiell. "Propagation of Photons through Optical Fiber: Spin-Orbit Interaction and Nonlinear Phase Modulation". Thesis, University of Oregon, 2016. http://hdl.handle.net/1794/20708.
Abstract (sommario):
We investigate two medium-facilitated interactions between properties of light upon propagation through optical fiber. The first is interaction between the spin and intrinsic orbital angular momentum in a linear optical medium. This interaction gives rise to fine structure in the longitudinal momenta of fiber modes and manifests in rotational beating effects. We probe those beating effects experimentally in cutback experiments, where small segments are cut from the output of a fiber to probe the evolution of both output polarization and spatial orientation, and find agreement between theoretical predictions and measured behavior.
The second is nonlinear optical interaction due to cross- and self-phase modulation between the complex-valued temporal amplitude profile of pump pulses and the amplitude profiles of generated signal and idler pulses in optical fiber photon-pair sources utilizing the four-wave mixing process named modulation instability. We develop a model including the effects of these nonlinear phase modulations (NPM) describing the time-domain wave function of the output biphoton in the low-gain regime. Assuming Gaussian temporal amplitude profiles for the pump pulse, we numerically simulate the structure of the biphoton wave function, in symmetric and asymmetric group velocity matching configurations. Comparing the overlap of the joint temporal amplitudes with and without NPM indicates how good of an approximation neglecting NPM is, and we investigate the effects of NPM on the Schmidt modes. We find that effects of NPM are small on temporally separable sources utilizing symmetric group velocity matching, but appreciably change the state of temporally entangled sources with the same group velocity matching scheme. For sources designed to produce entangled biphotons, our simulations suggest that NPM increases the Schmidt number, which may increase entanglement resource availability with utilization of a phase-sensitive detection scheme. We find that NPM effects on temporally separable sources designed with asymmetric group velocity matching produce non-negligible changes in the state structure. The purity is unaffected at perfect asymmetric group velocity matching, but if the pump is detuned from the correct wavelength, the purity degrades. The largest changes to the state due to NPM occur in long fibers with long pulse durations and low repetition rates.
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McLaren, Melanie. "Tailoring quantum entanglement of orbital angular momentum". Thesis, Stellenbosch : Stellenbosch University, 2014. http://hdl.handle.net/10019.1/95868.
Abstract (sommario):
Thesis (PhD)--Stellenbosch University, 2014.ENGLISH ABSTRACT: High-dimensional quantum entanglement offers an increase in information capacity per photon; a highly desirable property for quantum information processes such as quantum communication, computation and teleportation. As the orbital angular momentum (OAM) modes of light span an infinite-dimensional Hilbert space, they have become frontrunners in achieving entanglement in higher dimensions. In light of this, we investigate the potential of OAM entanglement of photons by controlling the parameters in both the generation and measurement systems. We show the experimental procedures and apparatus involved in generating and measuring entangled photons in two-dimensions. We verify important quantum tests such as the Einstein, Podolsky and Rosen (EPR) paradox using OAM and angle correlations, as well as a violation of a Bell-type inequality. By performing a full state tomography, we characterise our quantum state and show we have a pure, highly entangled quantum state. We demonstrate that this method can be extended to higher dimensions. The experimental techniques used to generate and measure OAM entanglement place an upper bound on the number of accessible OAM modes. As such, we investigate new methods in which to increase the spiral bandwidth of our generated quantum state. We alter the shape of the pump beam in spontaneous parametric down-conversion and demonstrate an effect on both OAM and angle correlations. We also made changes to the measurement scheme by projecting the photon pairs into the Bessel-Gaussian (BG) basis and demonstrate entanglement in this basis. We show that this method allows the measured spiral bandwidth to be optimised by simply varying the continuous radial parameter of the BG modes. We demonstrate that BG modes can be entangled in higher dimensions compared with the commonly used helical modes by calculating and comparing the linear entropy and fidelity for both modes. We also show that quantum entanglement can be accurately simulated using classical light using back-projection, which allows the study of projective measurements and predicts the strength of the coincidence correlations in an entanglement experiment. Finally, we make use of each of the techniques to demonstrate the effect of a perturbation on OAM entanglement measured in the BG basis. We investigate the self-healing property of BG beams and show that the classical property is translated to the quantum regime. By calculating the concurrence, we see that measured entanglement recovers after encountering an obstruction.
AFRIKAANSE OPSOMMING: Hoë-dimensionele kwantumverstrengeldheid bied ’n toename in inligtingskapasiteit per foton. Hierdie is ’n hoogs wenslike eienskap vir kwantum inligting prosesse soos kwantum kommunikasie, berekening en teleportasie. Omdat die orbitale hoekmomentum (OAM) modusse van lig ’n oneindig dimensionele Hilbertruimte beslaan, het dit voorlopers geword in die verkryging van verstrengeling in hoër dimensies. In die lig hiervan, ondersoek ons die potensiaal van OAM verstrengeling van fotone deur die parameters in beide die generering en meting stelsels te beheer. Ons toon die eksperimentele prosedures en apparaat wat betrokke is by die generering en die meet van verstrengelde fotone in twee dimensies. Ons verifieer kwantumtoetse, soos die Einstein, Podolsky en Rosen (EPR) paradoks vir OAM en die hoekkorrelasies, sowel as ’n skending van ’n Bell-tipe ongelykheid. Deur middel van ’n volledige toestand tomografie, karakteriseer ons die kwantum toestand en wys ons dat dit ’n suiwer, hoogs verstrengel kwantum toestand is. Ons toon ook dat hierdie metode uitgebrei kan word na hoër dimensies. Die eksperimentele tegnieke wat tydens die generasie en meet van OAM verstrengeling gebruik is, plaas ’n bogrens op die aantal toeganklik OAM modusse. Dus ondersoek ons nuwe metodes om die spiraal bandwydte van ons gegenereerde kwantum toestand te verhoog. Ons verander die vorm van die pomp bundel in spontane parametriese af-omskakeling en demonstreer die uitwerking daarvan op beide OAM en die hoekkorrelasies. Ons het ook veranderinge aan die meting skema gemaak deur die foton pare op die Bessel-Gauss (BG) basis te projekteer. Ons wys dat hierdie metode die gemeetde spiraal bandwydte kan optimeer deur eenvoudig die kontinue radiale parameter van die BG modes te verander. Ons demonstreer dat BG modusse verstrengel kan word in hoër dimensies as die heliese modusse, wat algemeen gebruik word, deur berekeninge te maak en te vergelyk met lineêre entropie en vir beide modusse. Ons wys ook dat kwantumverstrengling akkuraat nageboots kan word, met behulp van die klassieke lig terug-projeksie, wat die studie van projeksie metings toelaat en voorspel die krag van die saamval korrelasies in ’n verstrengeling eksperiment. Ten slotte, gebruik ons elk van die tegnieke om die effek van ’n storing op OAM verstrengling wat in die BG basis gemeet is, te demonstreer. Ons ondersoek die self-genesingseienskap van BG bundels en wys dat die klassieke eienskap vertaal na die kwantum-gebied. Deur die berekening van die konkurrensie (concurrence), sien ons dat die gemeetde verstrengeling herstel word nadat ’n obstruksie ondervind is.
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Chu, Jiaqi. "Orbital angular momentum encoding/decoding of 2D images for scalable multiview colour displays". Thesis, University of Cambridge, 2018. https://www.repository.cam.ac.uk/handle/1810/274903.
Abstract (sommario):
Three-dimensional (3D) displays project 3D images that give 3D perceptions and mimic real-world objects. Among the rich varieties of 3D displays, multiview displays take advantage of light’s various degrees of freedom and provide some of the 3D perceptions by projecting 2D subsampling of a 3D object. More 2D subsampling is required to project images with smoother parallax and more realistic sensation. As an additional degree of freedom with theoretically unlimited state space, orbital angular momentum (OAM) modes may be an alternative to the conventional multiview approaches and potentially project more images. This research involves exploring the possibility of encoding/decoding off-axis points in 2D images with OAM modes, development of the optical system, and design and development of a multiview colour display architecture. The first part of the research is exploring encoding/decoding off-axis points with OAM modes. Conventionally OAM modes are used to encode/decode the on-axis information only. Analysis of on-axis OAM beams referenced to off-axis points suggests representation of off-axis displacements as a set of expanded OAM components. At current stage off-axis points within an effective coding area are possible to be encoded/decoded with chosen OAM modes for multiplexing. Experimentally a 2D image is encoded/decoded with an OAM modes. When the encoding/decoding OAM modes match, the image is reconstructed. On the other hand, a dark region with zero intensity is shown. The dark region suggests the effective coding area for multiplexing. The final part of the research develops a multiview colour display. Based on understandings of off-axis representation of a set of different OAM components and experimental test of the optical system, three 1 mm monochromatic images are encoded, multiplexed and projected. Having studied wavelength effects on OAM coding, the initial architecture is updated to a scalable colour display consisting of four wavelengths.
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Maurer, Michael [Verfasser], e Yiannos [Akademischer Betreuer] Manoli. "System dimensioning, digital postprocessing, and nonideality control for electromechanical Delta-Sigma-Modulator based Angular Rate Detection". Freiburg : Universität, 2018. http://d-nb.info/1167159624/34.
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Mmbaga, Paul Fahamuel. "Study, analysis and application of optical OFDM, Single Carrier (SC) and MIMO in Intensity Modulation Direct Detection (IM/DD)". Thesis, University of Edinburgh, 2015. http://hdl.handle.net/1842/15952.
Abstract (sommario):
With the rapid growth of wireless data demands and saturation of radio frequency (RF) capacity, visible light communication (VLC) has become a promising candidate to complement conventional RF communication, especially for indoor short range applications. However the performance of the system depends on the propagation and type of system used. An optical Orthogonal Frequency Division Multiplexing (O-OFDM) together with multiple input multiple output (MIMO) in different scenario and modulation techniques are studied in the thesis. A novel optical wireless communication (OWC) multi-cell system with narrow field of view (FOV) is studied. In this system the intensity modulated beam from four light sources are used for communication. The system allows beams to be concentrated in specific areas of the room to serve multiple mobile devices with low interference and hence increase system capacity. The performance of asymmetrically clipped optical orthogonal frequency division multiplexing (ACO-OFDM), direct current biased optical OFDM (DCO-OFDM) and single carrier (SC) modulation are then compared in this system considering single user and multiusers scenarios. The performance of the multi-cell is compared with single cell with wide FOV. It is shown that the capacity for multi-cell system increases with the number of users to 4 times the single user capacity. Also the findings show that multi-cell system with narrow beams can outperform a single wide beam system in terms of coverage area and hence average throughput of about 2.7 times the single wide beam system capacity. One of the impairments in line of sight (LOS) OWC systems is coverage which degrades the performance. A mobile receiver with angular diversity detectors in MIMO channels is studied. The objective is to improve the rank of the channel matrix and hence system throughput. Repetition coding (RC), spatial multiplexing (SMP) and spatial modulation (SM) concepts are used to evaluate throughput across multiple locations in a small room scenario. A novel adaptive spatial modulation (ASM) which is capable of combating channel rank deficiency is devised. Since the receiver is mobile, the channel gains are low in some locations of the room due to the lack of LOS paths between transmitters and receivers. To combat the situation adaptive modulation and per antenna rate control (PARC) is employed to maximise spectral efficiency. The throughputs for fixed transmitters and receivers are compared with the oriented/inclined detectors for different cases. Angular diversity detectors offer a better throughput improvement than the state of the art vertical detectors, for example in ASM angular diversity receiver gives throughput of about 1.6 times that of vertical detectors. Also in SMP the angular detectors offer throughput about 1.4 times that of vertical detectors. SMP gives the best performance compared to RC, SM and ASM, for example SMP gives throughput about 2.5 times that of RC in both vertical detectors and angular diversity receivers. Again SMP gives throughput about 6 times that of SM in both vertical detectors and angular diversity receivers. Also SMP provides throughput about 2 times that of ASM in both vertical detectors and angular diversity receivers. ASM exhibit improvement in throughput about average factor of 3.5 times SM performance in both vertical detectors and angular diversity detectors. As the performance of the system may be jeopardized by obstructions, specular and diffuse reflection models for indoor OWC systems using a mobile receiver with angular diversity detectors in MIMO channels are considered. The target is to improve the MIMO throughput compared to vertically oriented detectors by exploiting reflections from different reflecting surfaces in the room. The throughput across multiple locations in the small room by using RC, SMP and SM approaches is again evaluated. The results for LOS only channels against LOS with specular or diffuse reflection conditions, for both vertical and angular oriented receivers are then compared. The results show that exploiting specular and diffuse reflections provide significant improvements in link performance. For example the reflection coefficient (α) of 0.9 and the antenna separation of 0.6 m, RC diffuse model shows throughput improvement of about 1.8 times that of LOS for both vertical detectors and angular diversity receivers. SM diffuse model shows throughput improvement of about 3 times that of LOS for both vertical detectors and angular diversity receivers. ASM diffuse model shows throughput improvement of about 2 times that of LOS for both vertical detectors and angular diversity receivers. SMP diffuse model shows throughput improvement of about 1.5 times that of LOS for both vertical detectors and angular diversity receiver.
Libri sul tema "Modulation angulaire":
1
1957-, Goupil M. J., Hansen Carl J e United States. National Aeronautics and Space Administration., a cura di. On the role of resonances in nonradial pulsators. [Washington, DC: National Aeronautics and Space Administration, 1997.
Capitoli di libri sul tema "Modulation angulaire":
1
Stevens, Peter M. "Growth Modulation for Angular and Length Correction". In Pediatric Lower Limb Deformities, 51–66. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-17097-8_4.
2
Redžić, M., A. Beganović, L. Čiva, R. Jašić, A. Skopljak-Beganović e S. Vegar-Zubović. "Quality control of angular tube current modulation". In IFMBE Proceedings, 563–67. Singapore: Springer Singapore, 2017. http://dx.doi.org/10.1007/978-981-10-4166-2_85.
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Gross, Richard S., Steven L. Marcus e Jean O. Dickey. "Modulation of the Seasonal Cycle in Length-of-Day and Atmospheric Angular Momentum". In International Association of Geodesy Symposia, 457–62. Berlin, Heidelberg: Springer Berlin Heidelberg, 2002. http://dx.doi.org/10.1007/978-3-662-04709-5_76.
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Djordjevic, Ivan B., e Zhen Qu. "Coded Orbital Angular Momentum Modulation and Multiplexing Enabling Ultra-High-Speed Free-Space Optical Transmission". In Optical Wireless Communications, 363–85. Cham: Springer International Publishing, 2016. http://dx.doi.org/10.1007/978-3-319-30201-0_16.
Atti di convegni sul tema "Modulation angulaire":
1
Hodgkinson, Ian, Qi hong Wu e Adrian McPhun. "Rugate filters with spatially-modulated nanostructures". In Optical Interference Coatings. Washington, D.C.: Optica Publishing Group, 1997. http://dx.doi.org/10.1364/oic.1998.fb.3.
Abstract (sommario):
We have designed and fabricated birefringent rugate filters (birugates) by modulating the columnar nanostructure of titanium oxide and zirconium oxide during vacuum deposition. To produce the modulation the angular position of the substrate, and hence the deposition angle, is changed in a systematic way by a computer-controlled stepper drive. The deposition parameters (deposition rate ≈ 0.1nm/s, oxygen back-fill pressure ≈ 2×10–4mbar and substrate temperature ≪ 300°C) are within a regime where columnar growth tracks the applied deposition angle, according to a modified version of the tangent rule.1
2
Sabet, Arash A., Eftyxios Christoforou, Benjamin Zatlin, Guy M. Genin e Philip V. Bayly. "Deformation of the Human Brain Induced by Mild Angular Acceleration". In ASME 2007 Summer Bioengineering Conference. American Society of Mechanical Engineers, 2007. http://dx.doi.org/10.1115/sbc2007-175638.
Abstract (sommario):
Deformation of the human brain was measured in tagged magnetic resonance images (MRI) obtained dynamically during angular acceleration of the skull. This study was undertaken to provide much needed experimental data for the quantitative study of traumatic brain injury (TBI). A custom device was made to impart mild angular acceleration to the skull of a human volunteer inside an MR scanner. Images with a superimposed grid of “tag” lines were obtained using spatial modulation of magnetization (SPAMM) in a fast gradient-echo imaging sequence. Images of the moving brain were obtained dynamically by synchronizing the imaging process with the motion of the head. The deformation of the brain was characterized quantitatively with Lagrangian strain. Strain fields showed reduced strain along the central fissure and to a lesser degree, the central sulcus, suggesting that divisions between regions of the brain may serve to mechanically isolate these regions. Results emphasize the critical role of the brain’s suspension, including the dura mater, falx cerebri, and tentorium membranes, in modulating its deformation.
3
Sison, Miguel, e Sophie Brasselet. "Real-time imaging of molecular organization by point scanning nonlinear fast polarization modulation". In Polarized light and Optical Angular Momentum for biomedical diagnostics, a cura di Jessica C. Ramella-Roman, Hui Ma, I. Alex Vitkin, Daniel S. Elson e Tatiana Novikova. SPIE, 2021. http://dx.doi.org/10.1117/12.2578547.
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Zotov, Sergei A., Igor P. Prikhodko, Alexander A. Trusov e Andrei M. Shkel. "Frequency modulation based angular rate sensor". In 2011 IEEE 24th International Conference on Micro Electro Mechanical Systems (MEMS). IEEE, 2011. http://dx.doi.org/10.1109/memsys.2011.5734490.
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Vicuña-Hernández, Verónica, Lorenzo Marrucci e Bruno Piccirillo. "Orbital angular momentum broadening in Poincaré beams". In Frontiers in Optics. Washington, D.C.: Optica Publishing Group, 2022. http://dx.doi.org/10.1364/fio.2022.jw4a.1.
Abstract (sommario):
We present a theoretical study and experimental measurements of a broadened orbital angular momentum power spectrum due to the phase modulation in the generation of spatially varying polarization beams and monstar singularities.
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Chen, Yanzi, Jin Jiang, Zeming Hu, Kun Yang, Chenhong Zhou e Zhengrong Lai. "Trellis Coded Modulation with Orbital Angular Momentum". In 2021 IEEE 6th International Conference on Signal and Image Processing (ICSIP). IEEE, 2021. http://dx.doi.org/10.1109/icsip52628.2021.9688600.
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Aghion, Cristian, Ovidiu Ursaru, Mihai Lucanu, Laurentiu Dimitriu e Liliana Vornicu. "Software Control for PWMA (Angular Pulse Width Modulation)". In 2007 International Symposium on Signals, Circuits and Systems. IEEE, 2007. http://dx.doi.org/10.1109/isscs.2007.4292754.
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Djordjevic, Ivan B. "Orbital angular momentum modulation for fiber-optics communication". In 2012 Opto-Electronics and Communications Conference (OECC). IEEE, 2012. http://dx.doi.org/10.1109/oecc.2012.6276613.
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Hao, Yanling, Bo Liu, Chunyang Yu e Guangtao Zhou. "Micromachined angular rate sensor allowing interchangeable operation in both amplitude modulation and frequency modulation". In 2014 IEEE/ION Position, Location and Navigation Symposium - PLANS 2014. IEEE, 2014. http://dx.doi.org/10.1109/plans.2014.6851368.
10
Chang. "Large angular aperture acousto-optic modulator". In Proceedings of IEEE Ultrasonics Symposium ULTSYM-94. IEEE, 1994. http://dx.doi.org/10.1109/ultsym.1994.401683.