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Littérature scientifique sur le sujet « Characteristic mode theory »

Auteur : Grafiati
Publié le 19 juillet 2023

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Articles de revues sur le sujet "Characteristic mode theory"

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Ren, Wenhua, Fan Wang et Guobin Ren. « Mode Coupling Analysis for a Mode Selective Coupler Using the Supermode Theory ». Photonics 9, no 2 (25 janvier 2022) : 63. http://dx.doi.org/10.3390/photonics9020063.

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In this paper, the mode selective coupler (MSC) is analyzed using the supermode theory. It is shown that all characteristic parameters of the MSC can be obtained using the propagation constants of the supermodes supported by the MSC structure. Simulation results show that the characteristic parameters calculated by the supermode theory match well with those calculated by the traditional coupled mode theory (CMT) near the phase matching point of the MSC structure. In practice, the propagation constants of the supermodes can be obtained using common finite element software directly, avoiding the complex double integral in the traditional CMT. This analysis based on the supermode theory gives a deeper insight into the characteristics of the MSC, providing a fast and accurate method for the analysis of MSCs, which is helpful for their design, fabrication and applications.
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Ghalib, Asim, et Mohammad S. Sharawi. « New antenna mode generation based on theory of characteristic modes ». International Journal of RF and Microwave Computer-Aided Engineering 29, no 6 (31 décembre 2018) : e21686. http://dx.doi.org/10.1002/mmce.21686.

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Li, Weiwen, Yongcong Liu, Jie Li, Longfang Ye et Qing Huo Liu. « Modal Proportion Analysis in Antenna Characteristic Mode Theory ». International Journal of Antennas and Propagation 2019 (13 février 2019) : 1–10. http://dx.doi.org/10.1155/2019/7069230.

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The characteristic mode theory (CMT) can provide physically intuitive guidance for the analysis and design of antenna structures. In CMT applications, the antenna current distribution is decomposed into the superposition of multiple characteristic modes, and the proportion of each current mode is characterized by the modal weighting coefficient (MWC). However, different characteristic currents themselves have different radiation efficiencies reflected by the eigenvalues. Therefore, from the perspective of the contribution to the radiation field, the modal proportion should be more accurately determined by the combination of the modal weighting coefficient and the mode current itself. Since the discrete mode currents calculated using the electromagnetic numerical method are distributed on the whole conductor surface, we can actually use the radiation field to quantify the modal proportion or estimate it using the far field in the maximum radiation direction. The numerical examples provided in the paper demonstrate that this modal proportion can effectively evaluate antenna performance.
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parvin, Mostafa, Javad Ahmadi-Shokouh et Hamideh Dashti. « Systematic feed locating in multi-mode MIMO antennas using characteristic mode theory ». AEU - International Journal of Electronics and Communications 126 (novembre 2020) : 153399. http://dx.doi.org/10.1016/j.aeue.2020.153399.

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Dai, Qi I., Qin S. Liu, Hui U. I. Gan et Weng Cho Chew. « Combined Field Integral Equation-Based Theory of Characteristic Mode ». IEEE Transactions on Antennas and Propagation 63, no 9 (septembre 2015) : 3973–81. http://dx.doi.org/10.1109/tap.2015.2452938.

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Kovtun, Andrei, Emin Nugaev et Andrey Shkerin. « Characteristic modes of vibration of Q-balls ». EPJ Web of Conferences 191 (2018) : 06018. http://dx.doi.org/10.1051/epjconf/201819106018.

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In this report, based on [1], we study analytically small perturbations of classically stable Q-balls in 3+1 dimensions. Models with flat and polynomial potentials are considered. We find that large Q-balls in the model with the flat potential possess soft modes. We also find a specific mode for Q-balls near the stability bound, which is related to the decay mode of Q-clouds. For these modes, the perturbation theory is applicable with respect to the relative frequency of an excitation.
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Yan, Sen, et Guy A. E. Vandenbosch. « Design of Wideband Button Antenna Based on Characteristic Mode Theory ». IEEE Transactions on Biomedical Circuits and Systems 12, no 6 (décembre 2018) : 1383–91. http://dx.doi.org/10.1109/tbcas.2018.2857466.

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Lv, Hai Wei, Ying Hui Li et Liang Li. « Dynamic Characteristic of Axially Moving Soft Sandwich Beam ». Advanced Materials Research 702 (mai 2013) : 275–79. http://dx.doi.org/10.4028/www.scientific.net/amr.702.275.

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A new sandwich beam theory is proposed by introducing independent variables of the displacements of face sheets, middle plane of soft core according to the incompression in transverse direction of traditional sandwich beam theory. Based on Hamilton principal, the governing equation of the system is established. Galerkin truncation method was used to solve the governing equation. It was found that (1) the first mode of the system displays that it is consistent with the traditional sandwich beam theory; (2) the second mode of the system shows that the soft core is in the state of tension or in compression; (3) the third mode of the system displays that the upper part and lower part of soft core are in different state (tension or compression); (4) The incompressible model of sandwich beam is the special form of soft sandwich beam we establish in this paper.
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Haykir, Y., et O. A. Civi. « Characteristic Mode Analysis of Unit Cells of Metal-Only Infinite Arrays ». Advanced Electromagnetics 8, no 2 (5 septembre 2019) : 134–42. http://dx.doi.org/10.7716/aem.v8i2.1014.

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Characteristic mode analysis of metal only unit cells of periodic structures is performed using Method of Moments based formulation. Ewald’s transformation is incorporated for a fast and cost efficient solution and the advantages over spatial Green’s function are discussed. The influence of the unit cell size on the characteristic modes is demonstrated. Various metal-only reflectarray elements are compared and their radiation characteristics are interpreted using the theory of characteristic modes. It is shown that characteristic modes of the unit cell can help us to understand the radiation and scattering behavior of the unit cell and this physical insight can be used in periodic array unit cell design.
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Zhong, Hua, Junhong Yu et Hanzheng Ran. « Characteristic Model-Based Discrete Adaptive Sliding Mode Control for System with Time Delay ». International Journal of Automation Technology 10, no 2 (4 mars 2016) : 282–87. http://dx.doi.org/10.20965/ijat.2016.p0282.

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A novel characteristic model-based discrete sliding mode control (CMDSMC) for time delay system is presented in this paper. Firstly, to solve the challenge of establishing a accurate and simple model for time delay system, characteristic theory is applied to establish characteristic mode with time delay. Secondly, due to the uncertainties of time delay system, discrete sliding mode control based on characteristic model is proposed and stability analysis is done. At last, two illustrative examples taken from literatures are included to indicate the simplicity and superiority of the proposed method.
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Thèses sur le sujet "Characteristic mode theory"

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Chukwuka, Ozuem Anthony. « Performance enhancement of integrated antennas using metamaterials and characteristic mode theory ». Thesis, Lille 1, 2020. http://www.theses.fr/2020LIL1I039.

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La demande de systèmes sans fil mobiles miniaturisés a accru le besoin d'intégrer des antennes électriquement petites qui se caractérisent généralement par de mauvaises performances et un faible rendement. Des approches telles que l'utilisation de diélectriques, de fentes, de composants parasites,… ont été appliquées au fil des années pour améliorer les performances de telles antennes. La plupart des méthodes existantes sont empiriques et basées sur des optimisations chronophages. D'autres approches comme l'optimisation du courant d'antenne basée sur l'analyse modale sont des approches systématiques qui ont été proposées. Il a également été montré que l'utilisation de matériaux artificiels appelés inclusions de métamatériaux comme élément parasite permet d'améliorer les performances de l'antenne à moindre coût. Cependant, le choix de la bonne inclusion pour une conception d'antenne est compliqué, en particulier lorsque l'antenne est non canonique et arbitraire.Dans cette thèse, nous proposons une méthode systématique pour améliorer les performances de l'antenne en utilisant l'inclusion de métamatériaux. La méthode est utilisée pour concevoir une antenne inspirée des métamatériaux avec le potentiel d'analyser à la fois les propriétés de rayonnement et de diffusion de la conception inspirée des métamatériaux. Il utilise l'approche modale caractéristique pour évaluer l'énergie quantitative stockée des inclusions de métamatériaux qui fournissent des informations quantitatives sur le comportement en champ proche de l'inclusion. L'approche modale de l'énergie stockée est comparée à l'approche des paramètres efficaces pour décrire les inclusions et elles montrent toutes deux une bonne concordance qualitative. Dans le processus de conception inspiré des métamatériaux, un mode caractéristique est appliqué pour obtenir un aperçu des propriétés de rayonnement de la structure et l'inclusion est choisie pour compenser l'énergie stockée de l'élément d'antenne en fonction de sa quantité d'énergie stockée modale. Le couplage entre l'antenne et l'inclusion est analysé en utilisant le coefficient de couplage intermodal. Il représente la diffusion entre l'antenne et l'inclusion et définit comment la distance de positionnement et de séparation entre les deux éléments affecte les performances globales du système inspiré des métamatériaux. La méthodologie proposée est validée avec un prototype qui montre une bonne concordance entre le résultat simulé et mesuré. La méthode proposée est en outre appliquée dans l'analyse de l'amélioration de l'antenne intégrée en utilisant le camouflage électromagnétique. Le manteau se couple à l'élément dans son voisinage et permet à l'élément d'antenne actif de fonctionner avec un meilleur rendement de rayonnement. La méthode proposée est donc diverse et utile pour la conception future de systèmes inspirés des métamatériaux avec des performances améliorées
The demand for miniaturized mobile wireless systems have increased the need to integrate electrically small antennas which are generally characterized by poor performances and low efficiency. Methods such as the use of dielectric, slots, parasitic components, … have been applied over the years to enhance the performance of such antennas. However they are empirical and based on time-consuming optimisations. Other methods like antenna current optimization based on modal analysis are systematic methods which have been proposed. It has also been shown that the use of artificial materials known as metamaterial inclusions as parasitic element help to improve antenna performance at lower cost. The choice of the right inclusion for an antenna design is complicated especially when the antenna is non-canonical and arbitrary.In this thesis, we propose a systematic method for enhancing the performance of antenna using metamaterial inclusion as a parasitic element. The method is used for designing parasitic metamaterial antenna with the potential to analyse both the radiation and scattering properties of the parasitic metamaterial design. It uses the characteristic modal method to evaluate the quantitative stored energy of metamaterial inclusions which provide quantitative information on the near-field behaviour of the inclusion. The modal stored energy method is compared to the effective parameter method for describing inclusions and they both show good qualitative agreement. In the parasitic metamaterial antenna design process, characteristic mode is applied to get an insight into the radiation properties of the structure and an inclusion is chosen to compensate the stored energy of the antenna element based on the quantity of its modal stored energy. The coupling between the antenna and the inclusion is analysed using the inter-modal coupling co-efficient. It represents the scattering between the antenna and the inclusion and defines how the positioning and separation distance between the two elements affect the overall performance of the metamaterial-inspired system. The proposed methodology is validated with a prototype that show a good agreement between the simulated and measured result. The method is further applied in investigating the enhancement of integrated antenna using electromagnetic cloaking. The cloak couples to the passive element in its vicinity and allow the active antenna element to operate with a better radiation efficiency. The proposed method show usefulness for future design of parasitic metamaterial systems with enhanced performance
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Kari, Nadia. « Design methodology and modal analysis of electricallysmall antennas integrated in lossy dielectric media ». Electronic Thesis or Diss., Université Gustave Eiffel, 2023. http://www.theses.fr/2023UEFL2024.

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La demande de systèmes de communication sans fil et autonomes miniaturisés a augmenté grâce au large besoin de technologies sans fil pour la surveillance de la santé des infrastructures de nos villes, dans la marine ou dans le domaine biomédical... Cependant, les antennes miniaturisées sont généralement caractérisées par de faibles efficacités et de mauvaises performances et, avec la présence de milieux à pertes dans le voisinage, l'amélioration de leurs efficacités ne devient pas une tâche simple. Les méthodes développées pour améliorer les performances des antennes électriquement petites (ESA) se concentrent généralement sur l'un des paramètres clés de l'antenne puisqu'il existe un compromis entre la taille, la bande passante, l'adaptation d'impédance et l'efficacité de rayonnement. La plupart de ces méthodes nécessitent des essais et des erreurs et reposent sur la compréhension du mécanisme physique de l'ESA. De plus, elles sont limitées aux structures canoniques. D'autre part, il existe des méthodes basées sur l'évaluation de l'énergie nette stockée dans la région de champ proche. En minimisant cette énergie stockée, le facteur de qualité peut être augmenté et le mécanisme de rayonnement peut être amélioré. Ces méthodes sont principalement basées sur l'utilisation de l'analyse modale qui décompose la réponse du courant de surface en modes et extrait les valeurs propres et les vecteurs propres de chaque mode. Il a également été démontré que l'utilisation de matériaux artificiels connus sous le nom de métamatériaux peut jouer un rôle clé dans la compensation énergétique (énergie magnétique couplée à l'énergie électrique et vice versa). Elle pourrait améliorer l'efficacité, atténuant ainsi les effets de puissance. Jusqu'à présent, ces méthodes ont été proposées pour les ESAs rayonnant en espace libre.L'objectif de cette thèse est donc de proposer une méthode générale de conception, d'analyse et d'amélioration des ESAs rayonnant dans les pertes.l'analyse et l'amélioration des ESAs rayonnant dans des milieux à pertes. Ce travail est basé sur l'évaluation de la méthode de l'énergie nette stockée et l'utilisation de la méthode de l'énergie nette stockée.d'énergie stockée et l'utilisation des métamatériaux pour atténuer les effets des pertes.Les méthodes modales sont également étudiées grâce à leurs métriques utiles et puissantes pour analyser la réponse électromagnétique de la structure dans les régions de champ proche et lointain. La méthode d'expansion Eigen (EEM) est utilisée pour évaluer les différentes mesures telles que les modes propres, les courants propres et l'énergie nette stockée afin d'obtenir des informations complètes sur la réponse électromagnétique de l'antenne lorsqu'elle est placée dans un milieu à pertes. Le modèle de substrat multicouche est utilisé pour concevoir le milieu environnant et chaque couche possède les propriétés diélectriques qui correspondent aux corps hôtes tout en conservant la structure rayonnante 3D. L'utilisation du modèle de substrat multicouche permet d'éviter les problèmes de temps des méthodes 3D classiques. La méthode générique proposée s'avère utile pour la conception et l'analyse des systèmes de métamatériaux parasites afin d'améliorer les petites antennes électriques dans les milieux complexes et à pertes
The demand for miniaturized wireless and autonomous communication system has climbed thanks to the wide need of wireless technologies for the monitoring of infrastructures health of our cities, in marine or in the bio-medical field … However, miniaturized antennas are generally characterized by low efficiencies and poor performances and with the presence of lossy media in the vicinity, enhancing its efficiencies becomes not straightforward task. Methods developed to enhance the performance of electrically small antennas ESAs are generally focused on one of the antenna key parameters since there is a compromise trade-off between the size, bandwidth, impedance matching and radiation efficiency. Most of these methods require trial and error and rely on understanding the physical mechanism of the ESA. Moreover, they are limited to canonical structures. On the other hand, there are methods based on the evaluation of the net energy stored in the near field region. By minimizing this stored energy, the quality factor can be enhanced and the radiation mechanism can be improved. These methods are principally based on the use of modal analysis that decompose the surface current response into modes and to extract the eigenvalues and eigenvectors of each mode. It has also been shown that the use of the artificial materials known as metamaterials can play a key role in energy compensation (magnetic coupled to electrical energy and vice versa). It could enhance efficiency, thus mitigating power effects. To date, these methods have been proposed for ESAs radiating in free space.The aim of this thesis is therefore to propose a general method for designing, analyzing andimproving ESAs radiating into lossy media. This work is based on the evaluation of the netstored energy method and the use of the metamaterials for mitigating the effects of losses.Modal methods are also investigated thanks to their useful and powerful metrics for analyzing the electromagnetic response of the structure in the near and far-field regions. The Expansion Eigen Method EEM is used to evaluate the different metrics such as the eigenmodes, eigencurrents and net stored energy to have a full information about the electromagnetic response of the antenna when it is placed in lossy media. The multi-layer substrate model is used to design the surrounding environment and each layer has the dielectric properties that correspond to the host bodies while keeping the 3D radiating structure. The use of the multi-layer substrate model is to avoid the time consuming issue of classical 3D methods. The proposed generic method show usefulness for designing and analyzing of parasitic metamaterials systems to enhance electrically small antennas in complex and lossy media
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Cabedo, Fabrés Marta. « Systematic design of antennas using the theory of characteristic modes ». Doctoral thesis, Universitat Politècnica de València, 2008. http://hdl.handle.net/10251/1883.

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El principal objetivo de esta tesis es demostrar que la Teoría de los Modos Característicos puede ser empleada de forma sistemática para diseñar antenas de hilo y antena planas. La gran ventaja de los modos característicos, frente a otros métodos de diseño, es la clara visión física que proporcionan de los fenómenos que contribuyen a la radiación de la antena. A través de numerosos ejemplos se demostrará como los modos característicos permiten comprender mejor el funcionamiento de una antena, de forma que el diseño de la misma se puede realizar de forma justificada y coherente. También se mostrará como la información proporcionada por los modos característicos puede ser aprovechada para seleccionar la forma más apropiada para el elemento radiante, al igual que para elegir una configuración de alimentación óptima que maximice el ancho de banda de impedancia. La Teoría de los Modos Característicos fue inicialmente formulada por Garbacz en 1968, y posteriormente refinada por Harrington y Mautz en 1971. Tradicionalmente, los modos característicos han sido empleados para sintetizar formas de antena, y para controlar la difracción de objetos mediante carga reactiva. Sin embargo, en la actualidad, la Teoría de los Modos Característicos ha caído prácticamente en el olvido, a pesar de que permite obtener una solución modal para la corriente, que es de gran utilidad a la hora de analizar problemas de análisis, síntesis y optimización de antenas y difractores. La Teoría de los Modos Característicos parte de la definición de un problema de autovalores que involucra la matriz de impedancia generalizada de la estructura, y que tras ser resuelto proporciona un conjunto de modos de corriente reales, que son los denominados modos característicos. Estos modos se corresponden con las resonancias naturales de la estructura y pueden ser obtenidos numéricamente para cuerpos conductores de forma arbitraria. Por otra parte, los modos característicos forman un conjunto de funciones cer
Cabedo Fabrés, M. (2007). Systematic design of antennas using the theory of characteristic modes [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/1883
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Elghannai, Ezdeen Ahmed. « NOVEL METHOD TO CONTROL ANTENNA CURRENTS BASED ON THEORY OF CHARACTERISTIC MODES ». The Ohio State University, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=osu1471871173.

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Wright, Seth. « Competence, Warmth, And Expectations : An Integration Of Status Characteristics Theory And The Stereotype Content Model ». Diss., The University of Arizona, 2015. http://hdl.handle.net/10150/556454.

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Over the last fifty years, researchers in Status Characteristics Theory (SCT) have conclusively demonstrated that within task groups, status differences between members influence the emergence of a power and prestige hierarchy within the group. According to the theory, this is accomplished through the activation of stereotypical expectations of group members' abilities. However, relatively little research has directly examined the cognitive process associated with expectation formation. During this same period, scholars within diverse subfields of psychology have suggested that there are two fundamental dimensions along which social judgments are made. These two dimensions have been referred to by various names, including instrumentality and expressivity, agency and communality, and competence and warmth. The most recent exploration of this idea can be found in the field of cognitive science as part of the Stereotype Content Model (SCM). The purpose of the current research is to integrate the basic propositions of SCT with the cognitive process outlined in SCM. In doing so, I hope to situate SCT within an expansive body of existing research, while suggesting a number of potentially useful directions for future research in SCT.
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Strojny, Brandan Thomas. « EXCITATION AND ANALYSIS OF CHARACTERISTIC MODES ON COMPLEX ANTENNA STRUCTURES ». The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1301006813.

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Liu, Duixian. « Some relationships between characteristic modes and Inagaki modes for use in scattering and radiation problems ». Connect to resource, 1986. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1144430762.

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Obeidat, Khaled Ahmad. « Design Methodology for Wideband Electrically Small Antennas (ESA) Based on the Theory of Characteristic Modes (CM) ». The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1274730653.

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Buhr, Dianne C. « Variability in the estimation of item option characteristic curves for the multiple-category scoring model ». Gainesville, FL, 1989. http://www.archive.org/details/variabilityinest00buhr.

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Rabah, Mhamad Hassanein. « Design methodology of antennas based on metamaterials and the theory of characteristic modes : application to cognitive radio ». Thesis, Lille 1, 2015. http://www.theses.fr/2015LIL10141.

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C’est dans la course au débit que de nouveaux systèmes de communications sans fil sont proposés aujourd’hui afin de répondre à cette demande. Il n’existe pas de technologie ou de standard unique pour remplacer toutes les autres technologies radio tout en satisfaisant l’ensemble des besoins de services et d’usages. Les futurs systèmes de communications devront donc permettre l’interopérabilité entre les dif- férents standards au niveau européen et mondial. L’émergence des technologies de la radio intelligente constitue aujourd’hui une solution originale et prometteuse pour répondre à ce challenge. Cependant, le déploiement de ces systèmes soulève encore de nombreux défis techniques notamment au niveau des antennes. Ces dernières doivent en particulier être capables de modifier leurs réponses en fréquences ou bien avoir une très large bande tout en minimisant la déformation des formes d’ondes. Elles doivent répondre aux besoins de cohabitation multi-systèmes et de miniaturisation. Or la miniaturisation et la largeur de bande sont limités par des contraintes physiques et les caractéristiques des matériaux les constituant. Les métamatériaux, des composites électromagnétiques artificiels, peuvent permettre la conception d’éléments rayonnants pour la radio intelligente avec un plus grand degré de liberté et à moindre coût. Cependant l’analyse de l’association des métamatériaux à des antennes ou éléments rayonnants n’est pas aisé, surtout quand les antennes prennent une forme arbitraire. Pour adresser ces challenges les techniques classiques de conception d’antennes ne sont pas suffisantes. Pour cela, nous proposons dans ce travail une approche basée sur la conception modale utilisant la théorie des modes caractéristiques. Cette approche démontre un potentiel remarquable dans la conception des antennes électriquement petites ainsi les antennes basées/inspirées des métamatériaux. En outre, l’évaluation des performances d’antennes à formes arbitraires en fonction des paramètres géométriques à été démontré sans considération d’une excitation prédéfinie. Ceci offre un énorme avantage pour les techniques basées sur l’optimisation des formes d’antennes. Finalement, une antenne très large bande dédiée au sondage du spectre est présentée. L’approche modale a été utilisée afin de garantir un diagramme du rayonnement stable sur toute la bande de fréquence ainsi qu’une bonne efficacité dans le régime électriquement petit. Plusieurs validations expérimentales sont également présentées
The rise of wireless communication systems and the big demand of high bit rate links have entailed researches to lie over new communications systems. With this diversity of wireless systems, flexibility for operating between different standards is strongly needed. Cognitive radio (CR) consist the future system that can offer this flexibility. The new features of CRs remains many challenges to their antennas. Miniaturization, isolation and bandwidth improvement, are all real needs and effective challenges. Especially when the geometry of the antenna become more complex in order to fit the terminal chassis. The use of metamaterials (MTM) has been introduced to overcome physics limitations in order to undertake these needs. The analysis of MTM in presence of radiating elements such antennas prove to be a challenge. In this thesis, an new approach to address these challenges is proposed. It is based on a modal concept using the theory of characteristic modes (TCM). It proves to be useful to analyse and design of electrically small antenna (ESA), metamaterial-inspired antennas and metamaterial-based antennas. Furthermore, the same approach is used to evaluate the antenna performances when surrounded by complex artificial materials by proposing closed formulas for the quality factor. This remains into a huge advantage in the antenna shape optimisation in the antenna industry. As a proof of concept, an extremely-wide-band antenna for underlay CR (sensing antenna) is developed using the proposed approach in order to have stable radiation pattern an high efficiency in the electrically small regime. An experimental validation of the performances of all the presented designs is also provided
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Livres sur le sujet "Characteristic mode theory"

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Chen, Yikai. Characteristics modes : Theory and applications in antenna engineering. Hoboken, New Jersey : John Wiley and Sons, Inc., 2015.

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Caractérisation et les modes de la narration dans le roman moderne : Théorie de narratologie caractérologique. New York : P. Lang, 1994.

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Franklin, James A. Revised simulation model of the control system, displays, and propulsion system for an ASTOVL lift fan aircraft. Moffett Field, Calif : National Aeronautics and Space Administration, Ames Research Center, 1997.

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Shishkin, Aleksey. Methods of digital processing and speech recognition. ru : INFRA-M Academic Publishing LLC., 2023. http://dx.doi.org/10.12737/1904325.

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The monograph discusses the theory, algorithms and practical methods of implementing digital processing and recognition of speech signals. The basics of mathematical analysis of digital signals necessary for speech processing are presented. The acoustic theory of speech formation with the construction of a general discrete model is briefly described. The main characteristic features of speech signals, as well as methods of their isolation are considered. Hidden Markov models and the architecture of traditional recognition systems based on them are described in detail. Weighted finite converters used to increase the efficiency and speed up the process of decoding acoustic signals are considered. The main architectures of artificial neural networks and examples of integrated (end-to-end) speech recognition systems based on them are presented. It is intended for students, postgraduates, researchers and specialists dealing with speech signal processing, pattern recognition and artificial intelligence.
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Yudaev, Vasiliy. Hydraulics. ru : INFRA-M Academic Publishing LLC., 2021. http://dx.doi.org/10.12737/996354.

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The textbook corresponds to the general education programs of the general courses "Hydraulics" and "Fluid Mechanics". The basic physical properties of liquids, gases, and their mixtures, including the quantum nature of viscosity in a liquid, are described; the laws of hydrostatics, their observation in natural phenomena, and their application in engineering are described. The fundamentals of the kinematics and dynamics of an incompressible fluid are given; original examples of the application of the Bernoulli equation are given. The modes of fluid motion are supplemented by the features of the transient flow mode at high local resistances. The basics of flow similarity are shown. Laminar and turbulent modes of motion in pipes are described, and the classification of flows from a creeping current to four types of hypersonic flow around the body is given. The coefficients of nonuniformity of momentum and kinetic energy for several flows of Newtonian and non-Newtonian fluids are calculated. Examples of solving problems of transient flows by hydraulic methods are given. Local hydraulic resistances, their use in measuring equipment and industry, hydraulic shock, polytropic flow of gas in the pipe and its outflow from the tank are considered. The characteristics of different types of pumps, their advantages and disadvantages, and ways of adjustment are described. A brief biography of the scientists mentioned in the textbook is given, and their contribution to the development of the theory of hydroaeromechanics is shown. The four appendices can be used as a reference to the main text, as well as a subject index. Meets the requirements of the federal state educational standards of higher education of the latest generation. For students of higher educational institutions who study full-time, part-time, evening, distance learning forms of technological and mechanical specialties belonging to the group "Food Technology".
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Sitnova, Irina, Vladimir Yadov et Svetlana Kirdina-Chendler. Institutional changes in modern Russia : activist-activity approach. ru : INFRA-M Academic Publishing LLC., 2023. http://dx.doi.org/10.12737/1871442.

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Dissatisfaction with societal structuralist approaches with culturological determinism characteristic of them resulted in another crisis of modern sociology. Traditional sociology ignored a person capable of making individual decisions and making informed choices, and in traditional economic theory this person hung in an airless space in the absence of supportive social structures. Sociologists began to show interest in what is happening in neo-institutional economic theory, and, moreover, intensively borrow its conceptual apparatus. Attempts to resolve the crisis are demonstrated today by theorists of the activist-activity direction M. Archer, E. Giddens, P. Shtompka, and in the field of economics - neo-institutionalists J. Commans, R. Krouse, D. North, T. Veblen, et al. The monograph represents the activist paradigm shared by us, the basic principle of which goes back to K. Marx's formula that people, being born under the same conditions, change them by their practical activities, changing themselves. The task of the research is to find an explanation for institutional changes in a certain value conceptual model and subsequently apply it to the analysis of Russian reality. For students, postgraduates and teachers of sociological universities and faculties.
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Mistrorigo, Alessandro. Phonodia. Venice : Edizioni Ca' Foscari, 2018. http://dx.doi.org/10.30687/978-88-6969-236-9.

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This essay focuses on the ‘voice’ as it sounds in a specific type of recordings. This recordings always reproduce a poet performing a poem of his/her by reading it aloud. Nowadays this kind of recordings are quite common on Internet, while before the ’90 digital turn it was possible to find them only in specific collection of poetry books that came with a music cassette or a CD. These cultural objects, as other and more ancient analogic sources, were quite expensive to produce and acquire. However, all of them contain this same type of recoding which share the same characteristic: the author’s voice reading aloud a poem of his/her. By bearing in mind this specific cultural objet and its characteristics, this study aims to analyse the «intermedial relation» that occur between a poetic text and its recorded version with the author’s voice. This «intermedial relation» occurs especially when these two elements (text and voice) are juxtaposed and experienced simultaneously. In fact, some online archives dedicated to this type of recording present this configuration forcing the user to receive both text and voice in the same space and at the same time This specific configuration not just activates the intermedial relation, but also hybridises the status of both the reader, who become a «reader-listener», and the author, who become a «author-reader». By using an interdisciplinary approach that combines philosophy, psychology, anthropology, linguistics and cognitive sciences, the essay propose a method to «critically listening» some Spanish poets’ way of vocalising their poems. In addition, the book present Phonodia web archive built at the Ca’ Foscari University of Venice as a paradigmatic answer to editorial problems related to online multimedia archives dedicated to these specific recordings. An extent part of the book is dedicated to the twenty-eight interviews made to the Spanish contemporary poets who became part of Phonodia and agreed in discussing about their personal relation to ‘voice’ and how this element works in their creative practice.
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Chen, Yikai, et Chao-Fu Wang. Characteristic Modes : Theory and Applications in Antenna Engineering. Wiley & Sons, Incorporated, John, 2015.

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Chen, Yikai, et Chao-Fu Wang. Characteristic Modes : Theory and Applications in Antenna Engineering. Wiley & Sons, Incorporated, John, 2015.

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Chen, Yikai, et Chao-Fu Wang. Characteristic Modes : Theory and Applications in Antenna Engineering. Wiley & Sons, Limited, John, 2015.

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Chapitres de livres sur le sujet "Characteristic mode theory"

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Wu, Borui, Lubin Hang, Jiyou Peng, Renhui Peng et Xiaobo Huang. « Multi-mode Motion Analysis of Sideward Opening Aircraft Door Based on Position and Orientation Characteristic Theory ». Dans Advances in Asian Mechanism and Machine Science, 335–41. Cham : Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-91892-7_31.

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Dhara, Reshmi. « Circular Polarized Octal Band CPW-Fed Antenna Using Theory of Characteristic Mode for Wireless Communication Applications ». Dans Lecture Notes in Electrical Engineering, 193–210. Singapore : Springer Singapore, 2021. http://dx.doi.org/10.1007/978-981-16-0289-4_15.

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Selten, Reinhard. « A Noncooperative Model of Characteristic-Function Bargaining ». Dans Theory and Decision Library C, 247–67. Dordrecht : Springer Netherlands, 1988. http://dx.doi.org/10.1007/978-94-015-7774-8_9.

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Veshkurtsev, Yury. « COMPUTER SIMULATION OF THE MODEM ». Dans THE FOUNDATIONS OF THE THEORY OF CONSTRUCTION OF NEW-GENERATION MODEMS, 142–55. au : AUS PUBLISHERS, 2022. http://dx.doi.org/10.26526/chapter_628a89252ca618.76723701.

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The monography presents the fundamentals of the theory of construction new-generation modems. Modems are built on the principles of statistical communication theory, based on the use of a random signal (chaos) as a carrier of information. In such a signal, a characteristic function is modulated, which is a fundamental characteristic of a random process. The signal modulation and demodulation method is patented and allows you to create modems with efficiency and noise immunity indicators several orders of magnitude higher than those of the known devices of the same name. New-generation modems immediately improve the technical characteristics of digital IT equipment by several orders of magnitude, since they work without errors in wired and radio channels when receiving one hundred duodecillion of binary symbols. The book is recommended for scientists and specialists in the field of digital communication systems, statistical radio engineering and instrumentation, and may be useful for graduate students, masters and students of relevant specialties.
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Shuai, Zhikang. « Time-Scale Model Reduction of Microgrid Based on Singular Perturbation Theory ». Dans Transient Characteristics, Modelling and Stability Analysis of Microgird, 133–60. Singapore : Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-8403-9_6.

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Shuai, Zhikang. « Spatial-Scale Model Reduction of Multi-Microgrid Based on Dynamic Equivalent Theory ». Dans Transient Characteristics, Modelling and Stability Analysis of Microgird, 161–84. Singapore : Springer Singapore, 2020. http://dx.doi.org/10.1007/978-981-15-8403-9_7.

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Veshkurtsev, Yury. « NOISE IMMUNITY OF THE MODEM IN THE CHANNEL WITH "WHITE" NOISE ». Dans THE FOUNDATIONS OF THE THEORY OF CONSTRUCTION OF NEW-GENERATION MODEMS, 48–98. au : AUS PUBLISHERS, 2022. http://dx.doi.org/10.26526/chapter_628a89252a3fa2.30236651.

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The monography presents the fundamentals of the theory of construction new-generation modems. Modems are built on the principles of statistical communication theory, based on the use of a random signal (chaos) as a carrier of information. In such a signal, a characteristic function is modulated, which is a fundamental characteristic of a random process. The signal modulation and demodulation method is patented and allows you to create modems with efficiency and noise immunity indicators several orders of magnitude higher than those of the known devices of the same name. New-generation modems immediately improve the technical characteristics of digital IT equipment by several orders of magnitude, since they work without errors in wired and radio channels when receiving one hundred duodecillion of binary symbols. The book is recommended for scientists and specialists in the field of digital communication systems, statistical radio engineering and instrumentation, and may be useful for graduate students, masters and students of relevant specialties.
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Veshkurtsev, Yury. « NOISE IMMUNITY OF THE MODEM IN THE CHANNEL WITH "NON- WHITE" NOISE ». Dans THE FOUNDATIONS OF THE THEORY OF CONSTRUCTION OF NEW-GENERATION MODEMS, 99–141. au : AUS PUBLISHERS, 2022. http://dx.doi.org/10.26526/chapter_628a89252b5337.85338589.

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The monography presents the fundamentals of the theory of construction new-generation modems. Modems are built on the principles of statistical communication theory, based on the use of a random signal (chaos) as a carrier of information. In such a signal, a characteristic function is modulated, which is a fundamental characteristic of a random process. The signal modulation and demodulation method is patented and allows you to create modems with efficiency and noise immunity indicators several orders of magnitude higher than those of the known devices of the same name. New-generation modems immediately improve the technical characteristics of digital IT equipment by several orders of magnitude, since they work without errors in wired and radio channels when receiving one hundred duodecillion of binary symbols. The book is recommended for scientists and specialists in the field of digital communication systems, statistical radio engineering and instrumentation, and may be useful for graduate students, masters and students of relevant specialties.
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Klinkenberg, Edwin L. « A Logistic IRT Model for Decreasing and Increasing Item Characteristic Curves ». Dans Essays on Item Response Theory, 173–92. New York, NY : Springer New York, 2001. http://dx.doi.org/10.1007/978-1-4613-0169-1_10.

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Davison, Edward J., et Amir G. Aghdam. « Characterization and Calculation of Approximate Decentralized Fixed Modes (ADFMs) ». Dans Advances in Statistical Control, Algebraic Systems Theory, and Dynamic Systems Characteristics, 223–44. Boston, MA : Birkhäuser Boston, 2008. http://dx.doi.org/10.1007/978-0-8176-4795-7_11.

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Actes de conférences sur le sujet "Characteristic mode theory"

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Pang, Hui, Juan Xu et Jianping Zhao. « Wideband Slot Antenna with Characteristic Mode Theory ». Dans 2022 International Applied Computational Electromagnetics Society Symposium (ACES-China). IEEE, 2022. http://dx.doi.org/10.1109/aces-china56081.2022.10064748.

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Dai, Qi I., et Weng Cho Chew. « On the low frequency theory of characteristic mode ». Dans 2015 IEEE 24th Electrical Performance of Electronic Packaging and Systems (EPEPS). IEEE, 2015. http://dx.doi.org/10.1109/epeps.2015.7347124.

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Chen, Yikai, et Shiwen Yang. « Characteristic mode theory for antennas with multilayered media ». Dans 2016 Progress in Electromagnetic Research Symposium (PIERS). IEEE, 2016. http://dx.doi.org/10.1109/piers.2016.7734504.

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Sai Ho Yeung et Chao-Fu Wang. « Characteristic Mode Theory for Practical HF Antenna Design ». Dans 12th European Conference on Antennas and Propagation (EuCAP 2018). Institution of Engineering and Technology, 2018. http://dx.doi.org/10.1049/cp.2018.0752.

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Dai, Qi I., et Weng Cho Chew. « On the low frequency theory of characteristic mode ». Dans 2016 IEEE Electrical Design of Advanced Packaging and Systems (EDAPS). IEEE, 2016. http://dx.doi.org/10.1109/edaps.2016.7874403.

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Wang, Chao-Fu. « Recent development of characteristic mode theory and its applications ». Dans 2016 IEEE International Workshop on Electromagnetics : Applications and Student Innovation Competition (iWEM). IEEE, 2016. http://dx.doi.org/10.1109/iwem.2016.7505012.

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Beni, Takaaki, et Hiroyuki Arai. « Selective Excitation of Platform Eigenmodes Using Characteristic Mode Theory ». Dans 2020 International Workshop on Electromagnetics : Applications and Student Innovation Competition (iWEM). IEEE, 2020. http://dx.doi.org/10.1109/iwem49354.2020.9237445.

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Dai, Qi I., Hui Gan, Weng Cho Chew, Qin S. Liu et Sheng Sun. « Characteristic mode theory based on combined field integral equation ». Dans 2015 IEEE International Symposium on Antennas and Propagation & USNC/URSI National Radio Science Meeting. IEEE, 2015. http://dx.doi.org/10.1109/aps.2015.7304970.

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Li, H., S. Sun et B. Wang. « Automatic feeding arrangement based on theory of characteristic mode ». Dans 2017 Sixth Asia-Pacific Conference on Antennas and Propagation (APCAP). IEEE, 2017. http://dx.doi.org/10.1109/apcap.2017.8420519.

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Miao, Liu, Lu Zhong Liang et Peng Qiang. « Metasurface Broadband Circularly Polarized Antenna with Characteristic Mode Theory ». Dans 2021 International Conference on Communications, Information System and Computer Engineering (CISCE). IEEE, 2021. http://dx.doi.org/10.1109/cisce52179.2021.9446009.

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Rapports d'organisations sur le sujet "Characteristic mode theory"

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Handa, Sudhanshu, Zhiyuan Liu, Gelson Tembo, Clement Adamba et Peter Mvula. An empirically driven theory of poverty reduction. Centre for Excellence and Development Impact and Learning (CEDIL), février 2023. http://dx.doi.org/10.51744/crpp4.

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The persistence of poverty, particularly in sub-Saharan Africa, means that public policy in this region continues to debate the right mix of supply- versus demand-side interventions that can move large groups of households out of extreme or ultra-poverty. There is unlikely to be a single approach that can transition all poor or ultra-poor households out of poverty. This paper describes the use of secondary evaluation data from four government unconditional cash transfer programmes (UCTs) to identify high- and low-flyers, that is, those households that are able to use the income shock to significantly improve their living standards and those who aren’t. The authors attempt to categorize the high- and low-flyers to create typologies based on their pre-shock characteristics. They also look at post-treatment behaviours to see what participants of these programmes did with the cash to improve (or not) their living standards. Putting together these different pieces of information (pre-treatment characteristics and post-treatment behaviours) can help with understanding the different pathways out of poverty, and ultimately contribute to a middle-range theory of sustained poverty reduction.
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Forero-Alvarado, Santiago, Nicolás Moreno-Arias et Juan J. Ospina-Tejeiro. Humans Against Virus or Humans Against Humans : A Game Theory Approach to the COVID-19 Pandemic. Banco de la República, mai 2021. http://dx.doi.org/10.32468/be.1160.

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Externalities and private information are key characteristics of an epidemic like the Covid-19 pandemic. We study the welfare costs stemming from the incomplete information environment that these characteristics foster. We develop a framework that embeds a game theory approach into a macro SIR model to analyze the role of information in determining the extent of the health-economy trade-off of a pandemic. We apply the model to the Covid-19 epidemic in the US and find that the costs of keeping health information private are between USD $5.9$ trillion and USD $6.7$ trillion. We then find an optimal policy of disclosure and divulgation that, combined with testing and containment measures, can improve welfare. Since it is private information about individuals' health what produces the greatest welfare losses, finding ways to make such information known as precisely as possible, would result in significantly fewer deaths and significantly higher economic activity.
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Clark, Andrew E. Demography and well-being. Verlag der Österreichischen Akademie der Wissenschaften, janvier 2021. http://dx.doi.org/10.1553/populationyearbook2021.deb02.

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Demography studies the characteristics of populations. One such characteristic is well-being: this was the subject of the 2019 Wittgenstein Conference. Here, I discuss how objective well-being domains can be summarised to produce an overall well-being score, and how taking self-reported (subjective) well-being into account may help in this effort. But given that there is more than one type of subjective well-being score, we would want to know which one is “best”. We would also need to decide whose well-being counts, or counts more than that of others. Finally, I briefly mention the potential role of adaptation and social comparisons in the calculation of societal well-being.
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Tanny, Josef, Gabriel Katul, Shabtai Cohen et Meir Teitel. Application of Turbulent Transport Techniques for Quantifying Whole Canopy Evapotranspiration in Large Agricultural Structures : Measurement and Theory. United States Department of Agriculture, janvier 2011. http://dx.doi.org/10.32747/2011.7592121.bard.

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Original objectives and revisions The original objectives of this research, as stated in the approved proposal were: 1. To establish guidelines for the use of turbulent transport techniques as accurate and reliable tool for continuous measurements of whole canopy ET and other scalar fluxes (e.g. heat and CO2) in large agricultural structures. 2. To conduct a detailed experimental study of flow patterns and turbulence characteristics in agricultural structures. 3. To derive theoretical models of air flow and scalar fluxes in agricultural structures that can guide the interpretation of TT measurements for a wide range of conditions. All the objectives have been successfully addressed within the project. The only modification was that the study focused on screenhouses only, while it was originally planned to study large greenhouses as well. This was decided due to the large amount of field and theoretical work required to meet the objectives within screenhouses. Background In agricultural structures such as screenhouses and greenhouses, evapotranspiration (ET) is currently measured using lysimeters or sap flow gauges. These measurements provide ET estimates at the single-plant scale that must then be extrapolated, often statistically or empirically, to the whole canopy for irrigation scheduling purposes. On the other hand, turbulent transport techniques, like the eddy covariance, have become the standard for measuring whole canopy evapotranspiration in the open, but their applicability to agricultural structures has not yet been established. The subject of this project is the application of turbulent transport techniques to estimate ET for irrigation scheduling within large agricultural structures. Major conclusions and achievements The major conclusions of this project are: (i) the eddy covariance technique is suitable for reliable measurements of scalar fluxes (e.g., evapotranspiration, sensible heat, CO2) in most types of large screenhouses under all climatic conditions tested. All studies resulted with fair energy balance closures; (ii) comparison between measurements and theory show that the model is capable in reliably predicting the turbulent flow characteristics and surface fluxes within screenhouses; (iii) flow characteristics within the screenhouse, like flux-variance similarity and turbulence intensity were valid for the application of the eddy covariance technique in screenhouses of relatively dilute screens used for moderate shading and wind breaking. In more dense screens, usually used for insect exclusions, development of turbulent conditions was marginal; (iv) installation of the sensors requires that the system’s footprint will be within the limits of the screenhouse under study, as is the case in the open. A footprint model available in the literature was found to be reliable in assessing the footprint under screenhouse conditions. Implications, both scientific and agricultural The study established for the first time, both experimentally and theoretically, the use of the eddy covariance technique for flux measurements within agricultural screenhouses. Such measurements, along with reliable theoretical models, will enable more accurate assessments of crop water use which may lead to improved crop water management and increased water use efficiency of screenhouse crops.
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O’Reilly, Jacqueline, et Rachel Verdin. Measuring the size, characteristics and consequences of digital work. Digital Futures at Work Research Centre, février 2022. http://dx.doi.org/10.20919/whfq8202.

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This working paper provides a summary assessment of the existing literature and data on digital forms of employment internationally. It illustrates the variability in how it is defined, how it is growing and what kind of risks are associated with these developments. Evaluation of these types of jobs is divided. On one hand, optimists point to the attractions and relative ease in finding employment on digital platforms; on the other hand, more critical perspectives argue that these employment contracts can result in exclusion from social protection systems. The evidence indicates that while overall a relatively small proportion of all employment digital work is growing, both on platforms as well as adoption amongst more traditional companies. The characteristics of digital workers can vary by region and occupation. Overall, they tend to be predominantly younger and more likely male, with a growing number of women albeit in particular occupations. Skills and earnings levels vary but the key issues of disputes is around pay, conditions and employment status. The consequences of this form of work for those with lower skilled digital employment can undermine their social citizenship: they lack comparable employment rights, or when unemployed entitlement to adequate social protection. The potential polarisation effects of digital exclusion and deficits will severely hamper the wider benefits of transparency offered by these technologies. During the pandemic these trends have become more apparent. The imbalance of bargaining power and regulatory governance to bridge gaps in citizenship entitlements undermines the collective potential of policy makers and trade unions to address these challenges. Nevertheless, there is emerging evidence of innovative challenges and contestation of these gaps by both union organisations and national regulators attempts to adapt social protection
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Pasimeni, Francesco, et Tommaso Ciarli. Reducing environmental impact through shared ownership : A model of consumer behaviour. UNU-MERIT, mai 2023. http://dx.doi.org/10.53330/bxen6934.

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We propose a simple model to study the conditions under which consumers prefer to purchase a good in coalition rather than individually. To identify those conditions, we study the full parameter space that defines the characteristics and preferences of heterogeneous consumers, the characteristics of the good, and the characteristics of a public service that offers the same services as the good. We find that shared ownership emerges only under niche conditions, for relatively lower income consumers with relatively higher demand. Furthermore, shared ownership is more likely to emerge if the shared good is relatively small and can be purchased in small coalition with lower coordination costs. Results are relevant to design sustainable consumption policies as they show that the diffusion of shared goods reduce the net number of goods in an economy, and therefore their environmental impact. However, we do not find any impact of shared ownership in reducing inequality in accessing goods. We show that policies that reduce the relative price of the shared purchase can accelerate the transition to a more sustainable shared consumption.
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Schultz, Timothy, Michael Zhou, Jodi Gray, Jackie Roseleur, Richard Clark, Dylan Mordaunt et Peter Hibbert. Patient characteristics and interventions associated with complaints and medico-legal claims. The Sax Institute, novembre 2022. http://dx.doi.org/10.57022/lioq6047.

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There is anecdotal evidence that the rate of complaints and claims against doctors is rising, yet little is known about (Q1) which types of patients are more likely to make a complaint or claim, nor about (Q2) what interventions are effective in reducing rates of complaints and claims and increasing patient satisfaction. This Evidence Check aimed to answer those two questions. The evidence base for both of the questions was of low quality, with only five studies having a comparison group. Twenty-five studies addressed Question 1. The only patient characteristic to have a consistent effect on rates of complaints and claims was having a mental, behavioural or developmental disorder. Other patient characteristics, including those related to their therapeutic context, had inconsistent or weak relationships with rates of complaints and claims. Twenty studies addressed Question 2 (including one which addressed both questions). There were consistently reduced rates of complaints and claims following implementation of risk management programs and also implementation of communication and resolution programs. Peer feedback programs consistently improved doctors’ response to complaints and subsequent performance. However, the results found here should be interpreted with caution, as the risk of bias inherent in the study designs makes them more likely to erroneously demonstrate an effect.
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Glennie, Alex, Nyangala Zolho et Hugo Cuello. A Comparison of the Characteristics of TAFTIE and RELAI Innovation Agencies. Inter-American Development Bank, novembre 2022. http://dx.doi.org/10.18235/0004551.

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This report brings together the results of a comparative analysis of the Latin American Network of Innovation Agencies (RELAI) and the European Network of Innovation Agencies (TAFTIE). This research has aimed to foster links between innovation agencies in Europe and Latin America in order to strengthen relationships and create opportunities for learning to take place. Our starting place is a comparison of the ways in which TAFTIE and RELAI agencies are similar, as well as the areas where they diverge. With this report, we hope to stimulate thinking about the variety of roles that innovation agencies can take on and how they can become more effective learning organizations, capable of adapting and evolving in response to changing contexts and able to learn from the experience of their peers worldwide.
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Sabogal-Cardona, Orlando, Lynn Scholl, Daniel Oviedo, Amado Crotte et Felipe Bedoya. Not My Usual Trip : Ride-hailing Characterization in Mexico City. Inter-American Development Bank, août 2021. http://dx.doi.org/10.18235/0003516.

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With a few exceptions, research on ride-hailing has focused on North American cities. Previous studies have identified the characteristics and preferences of ride-hailing adopters in a handful of cities. However, given their marked geographical focus, the relevance and applicability of such work to the practice of transport planning and regulation in cities in the Global South is minimal. In developing cities, the entrance of new transport services follows very different trajectories to those in North America and Europe, facing additional social, economic, and cultural challenges, and involving different strategies. Moreover, the determinants of mode choice might be mediated by social issues such as the perception of crime and the risk of sexual harassment in public transportation, which is often experienced by women in large cities such as Mexico. This paper examines ride-hailing in the Metropolitan Area of Mexico City, unpacking the characteristics of its users, the ways they differ from users of other transport modes, and the implications for urban mobility. Building on the household travel survey from 2017, our analytical approach is based on a set of categorical models. Findings suggest that gender, age, education, and being more mobile are determinants of ride-hailing adoption. The analysis shows that ride-hailing is used for occasional trips, and it is usually done for leisure and health trips as well as for night trips. The study also reflects on ride-hailings implications for the way women access the city.
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Roux, Anne M., Paul T. Shattuck, Jessica E. Rast et Kristy A. Anderson. National Autism Indicators Report : Developmental Disability Services and Outcomes in Adult. A.J. Drexel Autism Institute, mai 2017. http://dx.doi.org/10.17918/nairdevelopdisability2017.

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Many adults with autism have a difficult time achieving employment, continued education, and independent living. This report explores the experiences of adults with ASD who used services funded through state Developmental Disability (DD) agencies in 2014-15. We learn more about their characteristics, the quality of their lives, the opportunities they have to participate in their communities, their ability to exercise choice in their lives, and their access to needed services.
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