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This paper explores a new concept for the design of high scanning-range phased array antennas: the Interleaved Parasitic Arrays Antenna or IPAA. In this concept, we use periodic parasitic elements and the generator impedance to control the Active Voltage Standing Wave Ratio (AVSWR) over a wide scanning range. This new array architecture comes with a design methodology enabling a smooth step-by-step design process aiming at reducing the need for full-wave calculations. First, a numerical dual-polarization design is presented in detail to illustrate the methodology and to give the design keys to the reader. Then, a prototype working in the 5G C-band between 3.4 and 3.8 GHz (11% bandwidth) was designed using this methodology and measured for a 36-element array. It is meant to demonstrate and validate the mutual coupling management done by the interleaved parasitic arrays and the design process accuracy. Good correspondence between measurements and simulation was found and the proposed unit cell with its corresponding tile can be integrated in a larger phased array with active modules to perform beam steering over an important scanning range without deteriorating the AVSWR. The proposed unit cell is designed for a high-scanning range going from $\theta =0^{\circ }$ to $\theta = 70^{\circ }$ for every $\varphi $ -directions and shows an active reflection coefficient for an infinite array below −13.6dB.

We present the unit cell of a linearly polarised, ultra-wideband (UWB), wide scanning array antenna based on the tightly-coupled dipole antenna (TCDA) concept for cost-effective Ku/Ka-band SATCOM ground station applications. The TCDA unit cell is fed by a coaxial structure and several vias are used to broaden the bandwidth. In addition, a superstrate, functioning as a wide angle impedance matching (WAIM) layer, is employed to achieve together with an E-wall to reduce surface-waves. The simulated results show that the proposed TCDA provide a large bandwidth from 10.6-27.8 GHz at VSWR ≤ 2.0 at broadside radiation. Scanning angles up to 65° and 75° at the E- and H-plane, respectively, are maintained over the desired frequency of 12-1S GHz at VSWR ≤ 2.5.

This research presents a new idea in the use of wireless communication antennas: it uses a multi-layered array of cells called a superstrate multi-layer metasurface (MTM) and is placed in front of a patch of microstrip antenna to absorb surface waves and prevent them from passing through the insulating material, which reduces the permeability of the insulator and thus improves the Antenna properties, The proposed hexagonal cell with resonators is placed on the flame resistant (FR4) substrate, with a relative permittivity of 4.3 and an area (14×14) mm2 . It was tested when the metasurface layer is 4 mm in front of the patch and the distance between the metasurface layers is 2 mm. The optimum distances were calculated by the sweep parameter, and the improved antenna gain and the input reflection coefficient were obtained together. (S11) has been improved from -31.217 to -38.338 dB and, the gain from 3.28 dB to 6.554 dB.

The idea of passive biosensing through inductive coupling between antennas has been of recent interest. Passive sensing systems have the advantages of flexibility, wearability, and unobtrusiveness. However, it is difficult to build such systems having good transmission performance. Moreover, their near-field coupling makes them sensitive to misalignment and movements. In this work, to enhance transmission between two antennas, we investigate the effect of superstrates and metamaterials and propose the idea of dielectric fill in between the antenna and the superstrate. Preliminary studies show that the proposed method can increase transmission between a pair of antennas significantly. Specifically, transmission increase of ≈5 dB in free space and ≈8 dB in lossy media have been observed. Next, an analysis on a representative passive neurosensing system with realistic biological tissues shows very low transmission loss, as well as considerably better performance than the state-of-the-art systems. Apart from transmission enhancement, the proposed technique can significantly mitigate performance degradation due to misalignment of the external antenna, which is confirmed through suitable sensitivity analysis. Overall, the proposed idea can have fascinating prospects in the field of biopotential sensing for different biomedical applications.

In this paper, a $\varepsilon $ -negative metasurface superstrate is proposed for mutual coupling reduction of large antenna arrays. Unlike the previous decoupling metasurface works that are mostly confined to two-ports antennas, the proposed decoupling superstrate can be extended to massive multiple-input multiple-output (MIMO) systems. A $4\times 4$ antenna array is used as an example to illustrate the decoupling performance of the proposed metasurface. With the decoupling metasurface, the worst mutual coupling of the antenna array is improved by 8 dB over the operation bandwidth with a maximum mutual coupling reduction of 25 dB. Moreover, the decoupling metasurface also help restore the radiation patterns, bring down the active voltage sanding wave ratio, and broaden the bandwidth of the array.

This work builds a metamaterial (MTM) superstrate loaded on a patch of microstrip antenna for wireless communications. The MTM superstrate is made up of four G-shaped resonators on FR-4 substrate with a relative permittivity of 4.4 and has a total area of (8×16) mm2, and is higher than the patch. The MTM superstrate increases antenna gain while also raising the input reflection coefficient. When it is 9 mm above the patch, the gain increased from 3.28 dB to 6.02 dB, and when it is 7 mm above the patch, the input reflection coefficient was enhanced from -31.217 dB to -45.8 dB. When the MTM superstrate loaded antenna was compared to the traditional unloaded antenna, it was discovered that metamaterials have a lot of potential for improving antenna performance.

Kesterite-based solar cells still suffer from limited efficiency due to various problems related to the absorber and device interfaces. Absorber defects and non-ideal band alignment at the absorber/buffer hetero-interface, resulting in a cliff-like conduction band offset (CBO), and non-ideal absorber/back contact interfaces are the main factors limiting efficiency.This thesis focuses mainly on the absorber-related problems such as the secondary phases and the band alignment at the absorber-buffer heterojunction as well as the back interface.In the first part, the properties of the absorber layer were studied. Thin layers of Cu2ZnSnS4 (CZTS) were obtained by chemical route. This study revealed the formation of a pure kesterite phase with correct stoichiometry and oxidation state as well as good optical properties.Then, we estimated the band alignment at the CZTS-CdS hetero-interface experimentally by direct X-ray photoelectron spectroscopy (XPS) measurements. XPS spectroscopy was used to determine the valence band offset (VBO) directly by determining the valence band positions at the heterointerface.The conduction band offset (CBO) value was estimated based on UV/Visible spectroscopy band gap and VBO measurements. The results indicate that the CZTS-CdS heterojunction is type II with a negative cliff-like CBO.Next, we developed a new strategy to address the unfavorable CBO issue at the CZTS-CdS heterojunction by partial substitution of zinc. With this strategy, we were able to highlight a favorable spike-like CBO by partial substitution of Zn with Cd and nearly flat band CBO by partial substitution of Zn with Mn.Finally, a "superstrate" cell architecture was developed by reversing the technological process in order to overcome the back interface problem so as to facilitate the diffusion of the Cd from the buffer layer to the absorber with a view to obtaining an ideal band alignment. From our results, solar cells fabricated with this architecture using FTO and ITO as electrodes show interesting and promising performance. An efficiency of 2.44% was obtained for the ITO-based device, which represents the best current efficiency for this design., Les cellules solaires à base de kesterite souffrent toujours de rendement insuffisant. Leur efficacité est en effet limitée par plusieurs problèmes liés à l'absorbeur et aux interfaces des dispositifs. Les défauts de l'absorbeur, l'alignement non idéal de la bande à l'hétérointerface absorbeur/tampon, qui se traduit par un décalage de la bande de conduction (CBO) négative en forme de falaise, et les interfaces absorbeur/ contact arrière non idéales sont les principaux facteurs limitant le rendement.Cette thèse aborde les problèmes liés à l'absorbeur notamment les phases secondaires, l'alignement des bandes à l'hétérojonction absorbeur-tampon et l'interface arrière.Dans la première partie, les propriétés de la couche absorbante ont été étudiées. Des couches minces de Cu2ZnSnS4 (CZTS) ont été obtenues par voie chimique.Cette étude a révélé la formation d'une phase pure de kesterite avec une stoechiométrie et un degré d'oxydation corrects ainsi que de bons propriétés optiques.Ensuite, nous avons estimé l'alignement de la bande sur l'hétéro-interface CZTS-CdS expérimentalement par des mesures directes de spectroscopie photoélectronique à rayons X (XPS). La spectroscopie XPS a été utilisée pour déterminer le décalage de la bande de valence (VBO) directement en déterminant les positions de la bande de valence à l'hétérointerface.La valeur du décalage de la bande de conduction (CBO) a été estimée sur la base des mesures de la bande interdite par la spectroscopie UV/Visible et des mesures du VBO. Les résultats indiquent l’hétérojonction CZTS-CdS est de type II avec un CBO négative de type “cliff”.Ensuite, nous avons développé une nouvelle stratégie pour résoudre le problème du CBO défavorable au niveau de l'hétérojonction CZTS-CdS par substitution partielle du zinc. Grâce à cette stratégie, nous avons pu mettre en évidence un CBO positif de type "spike" par substitution partielle de Zn avec Cd et un CBO à bande presque plate par substitution partielle de Zn avec Mn.Enfin, une architecture cellules "superstrat" qui consiste à inverser le procédé technologique a été développée afin de remédier le problème de l'interface arrière et de favoriser la diffusion du Cd de la couche tampon vers l'absorbeur en vue de former un alignement de bande idéal.D'après nos résultats, les cellules solaires fabriquées avec cette architecture en utilisant le FTO et l'ITO comme électrodes montrent des performances intéressantes et prometteuses. Un rendement de 2,44 % a été obtenu pour le dispositif à base d'ITO, ce qui représente le meilleur rendement actuel pour cette architecture.

The effect of using a superstrate dielectric layer on an on-head matched antenna for biomedical diagnosis applications is investigated. Two on-head matched antennas are considered with different length meandered lines ensuring operation around 0.9 GHz frequency. The first antenna&rsquo, s conductive radiating structure is in direct contact with the head phantom, whereas the second one utilises a 0.5 mm thick superstrate layer on top of the conducting layer as a buffer. The lateral dimensions of both antennas are held constant at 30 &times, 30 mm2. The electric and magnetic field distribution is analysed and the power penetration, 50 mm inside the head phantom, is derived from the electromagnetic field surrounding the antennas. Both homogeneous and inhomogeneous head phantoms are considered while evaluating the antennas in terms of their reflection coefficient, current distribution, electric field, magnetic field, specific absorption rate (SAR) and power penetration inside the head. The antennas are fabricated and measured utilizing an inhomogeneous phantom to validate the proposed performance improvement using a superstrate. It is shown that the superstrate antenna achieves a ~8 dB increase in power penetration inside the head phantom along with a 0.0731 W/kg decrease in SAR compared to the antenna without a superstrate.

Gain and bandwidth enhancement of low profile, linearly polarized square dense dielectric patch antennas using a frequency selective surface (FSS) superstrate layer is proposed. A high dense dielectric patch antenna is utilized as a radiating element instead of a metallic patch in order to gain several significant advantages, including low profile, wide bandwidth, and high radiation efficiency. The implemented antenna is excited by an aperture-coupled feeding technique. The antenna gain is enhanced by using a highly reflective FSS superstrate layer, realizing an antenna gain enhancement of 11 dBi. The implemented antenna acquired a measured gain of about 17.78 dBi at 28 GHz with a 9% bandwidth and radiation efficiency of 90%. The bandwidth of the proposed antenna is improved by using a unit cell printed on two sides, as it provides a positive phase gradient over the desired frequency range. The antenna impedance bandwidth is broadened and the measured impedance matching $S{11}$ exhibited a 15.54% instead of 9% bandwidth while maintaining a high-gain characteristic of about 15.4 dBi. The implemented antenna presents a solid radiation performance with good agreement between the measured and simulation results. For some attractive advantages such as low profile, low cost, lightweight, small size, and ease of implementation, the proposed antenna is a very good candidate for millimeter-wave wireless communications.

Je přirozené, že se jednotlivé jazyky od sebe liší. Díky těmto rozdílům mluvíme o samostatných jazycích. Jazykovou interferencí rozumíme vzájemné přejímání některých jazykových prostředků z jednoho jazyka do druhého. Výskyt interference podmiňují různé faktory, např.: 1) nedostatečné ovládání cizího jazyka; 2) značná podobnost mezi cílovým a mateřským jazykem; 3) slabá koncentrace mluvčího. Tento příspěvek si klade za cíl zdůraznit mechanismy vedoucí k interferenci a její následky.

This research has proposed a switchable beam rectangular microstrip antenna with double parasitic patches, in which two PIN diodes were deployed for manipulation of the main beam direction and a superstrate (i.e. either a dielectric slab or metamaterial) for enhancement of the antenna gain. The dielectric slab is a second FR4 substrate while the metamaterial (MTM) is the 7×17 periodic structure of planar cycloid dipoles (PCD). Simulations were carried out and three different antenna prototypes (i.e. the proposed switchable beam rectangular microstrip antenna, the proposed antenna either with dielectric slab or MTM) fabricated and experimented. The simulation and experimental results are in good agreement and exhibit good impedance matching (|S11| less than 10dB) along the operating frequency. The average measured gain is 7 dBi with the unidirectional radiation pattern along the operating frequency. The proposed switchable antennas with and without the superstrate are operable in the 2.4-2.5 GHz WLAN system and switchable in three directions of 0 deg, 30 deg and 330 deg (xy-plane). Moreover, the findings validate the applicability of either the dielectric slab or three MTM block-layers as the superstrate to improve the antenna gain.

International audience; In this work, a novel stacked patch antenna array for future 5G applications is proposed. Initially, a single stacked patch antenna is designed to operate at 26 GHz band while maintaining good performances of bandwidth and gain. Better performances are obtained by stacking the superstrate layer above the antenna structure, thereby improving the gain and the bandwidth. The proposed antenna covers the frequency band from 23.02 GHz to 26.12 GHz resulting in a wide bandwidth with a compact size of 13*12 mm². Performances of the antenna are improved by incorporating an array of 2 identical elements based on the single designed patch antenna, resulting in a higher gain. The proposed array consists of 2 elements using 0.65 mm AR1000 substrate. The two element antenna array shows a good performance in terms of bandwidth (1.7 GHz) and gain reaching 12 dBi with a size of 13*25mm². The proposed designs are a great potential application for deployment in 5G generation

In this paper, a low cross-polarization improved-gain rectangular patch antenna is presented. A patch-ground shorting pin with defected patch structure (DPS) is introduced to suppress the cross-polarization level. A High Reflective Frequency Selective Surface (HRFSS) superstrate is designed and placed over the proposed antenna at an optimized position to intensify the gain. To characterize the unit-cell of the superstrate, its transmission characteristics are extracted and discussed. Integration of the superstrate achieves a beam contraction resulting in a gain enhancement to 10.65 dBi. The proposed antenna has perfect broadside radiation with a cross-polarization level of below &minus, 30 dB in the entire half power beamwidth. The prototype of the antenna exhibits good agreement between experimental and simulated results.

International audience; In practice, it was found that the choice of the substrate or superstrate material of printed antennas is of a great importance and plays a significant role in achieving the optimum resonant characteristics of the antenna; Uniaxial dielectrics have drawn more attention due to their availability in materials such as sapphire, boron nitride and Epsilam-10 ceramic-impregnated Tefon. Previous studies of anisotropic materials used in microwave devices indicate that the effects of anisotropy on the performance of such structures particularly in high frequencies cannot be ignored. Three very popular full wave methods that can be used to characterise microstrip patch antennas are: the finite element method, the finite difference time domain method, and the moment method. The last one also known as the full-wave method is arguably the most popular method for the analysis of microstrip antennas. In this work, resonant characteristics (the resonant frequency, the Half-power bandwidth) of an annular microstrip patch printed on uniaxially anisotropic substrate and covered with an anisotropic superstrate layer are studied using an electric field integral equation and the spectral domain Green's function. In order to validate the present method, we have confronted our results with theoretical and experimental data from the literature and very Good agreements were obtained between our computed data and measurements, and the convergence of the method is proven.

Gain enhancement of a wide slot antenna over a wide frequency band using a low profile, second order bandpass frequency selective surface (FSS) as a superstrate is presented in this paper. The proposed multilayered FSS with non-resonant unit cells in each layer allows in-phase transmission of waves radiated from the antenna over a 3dB bandwidth of about 50%. The design allows an enhancement of upto 4dBi in the antenna gain over the entire frequency band (5-8GHz) of operation. The FSS provides a very low insertion loss between the two transmission poles along with a linearly decreasing transmission phase over the band. The composite structure shows an impedance bandwidth (-10dB) of 65% with an average gain between 6-8dBi over the frequency band with a peak gain of 9dBi. Measurement results of the fabricated prototype matches well with the predicted values.

A wide band EBG resonator antenna with two layer of dielectric superstrates of the same material is design which is operating in X band. The EBG superstrates act as Partially Reflective Surfaces (PRS) having positive reflection phase curve which are suspended above a double sided dipole patch antenna fed by a coaxial cable pass through ground plane. Thus a resonator cavity is constructed which increases the bandwidth and gain of the feed antenna. The measured results validate the simulation results obtain from Computer Simulation Technology (CST) microwave studio. These results show that the antenna posses a 3 dB gain bandwidth from 8.5 GHz to 11.2 GHz, with a peak gain of 15.3 dBi. Furthermore, the scattering parameter S11 is well within range from 8.6 GHz to 11 GHz.

A high-gain rectangular waveguide-fed aperture antenna that uses a Spidron fractal structure to produce circular polarization is proposed. The antenna consists of a Spidron fractal aperture etched onto the ground plane of a dielectric substrate that is directly excited by a WR (Waveguide Rectangular)-90 waveguide-to-coax adapter. A superstrate was implemented at an appropriate distance above the antenna to enhance the broadside gain significantly. An antenna prototype was fabricated and tested to validate the design. The measured impedance bandwidth for | S 11 | &le, &minus, 10 dB is 9.89&ndash, 11.58 GHz (15.74%). The corresponding measured 3 dB axial ratio (AR) bandwidth is 10.68&ndash, 11.00 GHz (2.95%), and within the measured 3 dB AR bandwidth, a maximum realized gain of 9.59 dBic is achieved. The radiation patterns of the proposed antenna are presented and discussed.

A high-efficient and high-gain aperture coupled patch antenna with superstrate at 60 GHz is studied and presented. It is noted that adding superstrate will result in a significant effect on the antenna performances, and the size of the superstrate is critical for the optimum performance. The maximum measured gain of a single antenna with superstrate is 14.6 dBi, which is higher than that of a classical 2 x 2 array. It is found that the gain measured of a single antenna with superstrate increases nearly 9 dB at 60 GHz over its basic patch antenna. This superstrate antenna gives a very high estimated efficiency of 76%. The 2:1 measured VSWR bandwidth with superstrate is 6.8%. The radiation patterns are found to be broadside all over the frequency band. Also, this letter explains a comparison to another source of parasitic patch superstrate antenna with normal microstrip coupling. It is found that aperture coupling is better for high-gain antenna applications.

Planar superstrates constituted by Chiral Metamaterials structures can transform the radiation properties of an antenna. In this communication, an asymmetric chiral metamaterial based structure is proposed. Due to the lack of C4 symmetry in the design, the transmission coefficients depend on the incident wave polarization and display high transmission for one circular polarization but low transmission for the other one. The proposed structure is then used to improve the radiation characteristics of a microstrip patch antenna. Taking advantage of the properties of the asymmetric chiral structure, the polarization of the radiated field is modified, transforming the linear polarization of the microstrip antenna into a circular one. This work has been partially supported by the Spanish Government MINECO through the FEDER co-funded Research Project TEC2014-55463-C3-3-P and the Research Project TEC2012-33321.

Gain enhancement of a wide slot antenna over a wide frequency band using a low profile, second order bandpass frequency selective surface (FSS) as a superstrate is presented in this paper. The proposed multilayered FSS with non-resonant unit cells in each layer allows in-phase transmission of waves radiated from the antenna over a 3dB bandwidth of about 50%. The design allows an enhancement of upto 4dBi in the antenna gain over the entire frequency band (5-8GHz) of operation. The FSS provides a very low insertion loss between the two transmission poles along with a linearly decreasing transmission phase over the band. The composite structure shows an impedance bandwidth (-10dB) of 65% with an average gain between 6-8dBi over the frequency band with a peak gain of 9dBi. Measurement results of the fabricated prototype matches well with the predicted values.

The optical properties of microcrystalline silicon substrate-type solar cells with a front ZnO thickness of 500-1000 nm as required for monolithic series connection in PV-modules are investigated. The surface texture of the front ZnO was varied to study the possibility to reduce reflection losses and to improve light trapping. Before encapsulation, certain textures of the front ZnO exhibit improved light coupling for substrate solar cells. For substrate solar cells encapsulated with EVA and a glass cover, however, additional texture of the front ZnO has hardly any effect. Encapsulation also removes the antireflection conditions in case that the front ZnO was originally designed as ARC. So far, the quantum efficiency of encapsulated substrate solar cells does not show the high level as observed in superstrate solar cells possibly due to parasitic absorption in the front and back contact and the not optimized texture of the reflector (substrate). (C) 2002 Elsevier Science B.V. All rights reserved.

This article presents specific character of antroponimic system of the Chelmia territory and the Volynia viovodship in the XVI–XVII century. The context of this study are the origins of names constituting this system. Polish-Ukrainian language relations, their political and cultural conditions as well as Polish colonisation of this land and foreign influences on the native borderlands name-giving were drawn to attention. On the one hand the observed phenomenon of interference and assimilation occurred under the influence of the substrate of the Ukrainian language, on the other hand under the influence of Polish superstrate from Volyn and eastern part of Chelm district, or vice versa, in areas of the dominance of the Polish population of the substrate under the influence of Polish and Ukrainian superstrate. The specific language of the researched area is also proved by the occurrence of names of provenance German, Lithuanian, English and Hungarian. У статті представлено специфіку антропонімічних систем, що функціонували на території Холмського та Волинського воєводства у XVI–XVII ст. Звертаємо увагу на польсько-українські мовні контакти, їхній зв’язок із політично-культурною ситуацією й колонізацією східних земель давньої Речі Посполитої, а також на іншомовні впливи в питомому іменуванні пограниччя. Вдалося встановити явища інтерференції та асиміляції, які відбувалися, з одного боку, під впливом українського мовного субстрату, а з іншого боку, – польського субстрату (на Волині, а також у частині Східної Холмщини), або навпаки - під впливом польського субстрату та субстрату українського (на територіях, на яких переважало польське населення). Про мовну специфіку досліджуваної території свідчило також існування назв, що походили з німецької, литовської, англійської та угорської мов.

In this letter, we proposed a comparative study of a rectangular Microstrip patch antenna at Terahertz (THz) frequency ranging from 0.6 to 0.8 THz with and without superstrate. First, the simulation was carried to a simple micro-strip antenna, was then added an upper layer (superstrate) by varying the height to improve impedance matching and optimizing the performance of the antenna. The matching bandwidth and the maximum radiation gain obtained are around 22.47 % (10.43 dBi at 0.6929 THz), respectively. The performance of the dielectric resonator antenna is simulated by electromagnetic simulator CST Microwave Studio.

Translation is a linguistic activity which plays an essential role in the life of various human communities. Considered as a tool of communication and knowledge of the others, several disciplines were dedicated to it. In the XVIIIth century, the faculty of languages (al-Alsun) was established in Egypt by Rifāʽa al-Tahtāwī, the author of Taḫlīṣ al-ibrīz fi talḫlīṣ Bārīz. This work was translated in the XXth century by Anouar Louca under the title of “L’Or de Paris” which means “The Gold of Paris”. The study hereby presented deals with a work that presents a meticulous description of the journey of Rifāʻa al-Ṭahṭāwī in France. The latter work is Taḫlīṣ al-ibrīz fi talḫīṣ Bārīz and belongs to the period of Nahḍa of the Arabic literature.The study consists of four chapters: The first chapter presents a comparison between the aesthetic analysis from Taḫlīṣ and its translation, namely Or de Paris, into the french langage. The chapter explains the demonstrations of both objectives of the Nahḍa in the Taḫlīṣ and the strategies adopted by Louca in his Or de Paris.The second chapter presents a sociolinguistic analysis of Taḫlīṣ and Or de Paris. This analysis highlights the intrinsic link between the language and the society. A comparison of the Taḫlīṣ in its original language and its translation emphasizes the strategy of Louca and the differences between the original work and its translation.The Third chapter discusses the problem of the loyalty according to the interpretative theory. The room for manoeuvre and the processes used by Louca will be discussed.The fourth chapter is a selective semantic analysis of certain passages in Taḫlīṣ and their translations in Or de Paris. The analysis concerns the title, the first paragraph and the translation of the constitutional chart of 1814 made by Rifāʻa al-Ṭahṭāwī. The Four chapters proceed in a parallel pattern between the original work Taḫlīṣ and its translation.We recognize the difficulty of the task carried out by Louca given the wealth of the work of Rifāʻa al-Ṭahṭāwī which represents a bend in the history of the Arabic literature. The cultural, aesthetic, historical and linguistic specificity constitute a real challenge in the translation.; La traduction est une activité linguistique qui joue un rôle primordiale dans la vie des différentes communautés humaines. Considérée comme moyen de communication et de connaissance de l’autre, plusieurs disciplines lui ont été consacrées. Au XVIIIème siècle, la faculté des langues (al-Alsun) a été instaurée en Égypte par Rifāʽa al-Tahtāwī, l’auteur de Taḫlīṣ al-ibrīz fi talḫlīṣ Bārīz. Cette œuvre a été traduite au XXème siècle par Anouar Louca sous le titre de l’Or de Paris. L’Étude présente porte sur une œuvre qui présente une description minutieuse du séjour de Rifāʻa al-Ṭahṭāwī en France, à savoir le Taḫlīṣ al-ibrīz fi talḫīṣ Bārīz. Cette œuvre appartient à l’époque de la Nahḍa de la littérature arabe.L’étude porte sur quatre chapitres : Le premier chapitre entame analyse esthétique comparée du Taḫlīṣ et de l’Or de Paris. Le chapitre explique les manifestations des deux versants de la Nahḍa dans le Taḫlīṣ et les stratégies adoptées par Louca dans son Or de Paris.Le deuxième chapitre présente une analyse sociolinguistique du Taḫlīṣ et de l’Or de Paris. Cette analyse met en lumière le lien intrinsèque entre la langue et la société. Une comparaison de l’œuvre dans sa langue source et sa traduction mettra l’accent sur la stratégie de Louca et sur les différences entre l’original et la traduction.Le troisième chapitre porte sur la problématique de la fidélité selon la théorie interprétative. La marge de liberté et les procédés utilisés par Louca seront discutés. Le quatrième chapitre est une analyse sémantique sélective d certains passages dans le Taḫlīṣ et leurs représentations dans l’Or de Paris. L’analyse va porter sur le titre, le premier paragraphe et la traduction faite par Rifāʻa al-Tahtāwī de la charte constitutionnelle de 1814. Les quatre chapitres procèdent par une mise en parallèle de l’œuvre original et de sa traduction.Nous reconnaissons la difficulté de la tâche assumée par Louca vu la richesse de l’œuvre de Rifāʻa al-Tahtāwī qui représente un tournant dans l’histoire de la littérature arabe. La spécificité culturelle, esthétique, historique et linguistique constitue un vrai défi à la traduction.

In this paper, the influence of the EBG structures on the far-field pattern of patch antennas is investigated. As a reference model, a conventional rectangular patch antenna on a high-permittivity substrate is used. The reference model is consequently equipped by an EBG substrate (instead of the conventional one), and by an EBG cover (so called EBG superstrate). The changes in the farfield radiation patterns are discussed. In the second part of the paper, the substrate is perturbed by two different EBG structures designed for the coverage of two operation bands.

This paper proposes an efficient high-gain multilayered antenna for wireless applications. The prototype antenna consists of a microstrip antenna which fed single or multiple parasitic patches fabricated on a low cost easily available FR4 superstrate. The patches on superstrate are suspended in air at an integral multiple of λo/2. The structured is designed, fabricated and tested. The measured VSWR [lt] 2 at 5.725–5.875-GHz frequency band. The proposed antennas with single parasitic patch provide 87% efficiency, SLL of −17 dB with an associated gain of 13.5 dB. The gain increases to 17.1 dB with three parasitic patches. The proposed structure can be packaged inside an application platform. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 1923–1929, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23536

This article proposes an efficient high-gain multilayer 2×2 antenna array for wireless applications. The prototype antenna consists of a microstrip antenna which feeds 2×2 array of square parasitic patches fabricated on a low-cost easily available FR4 superstrate. The patches on superstrate are suspended in air at λ0/2. The structure is designed, fabricated, and tested. The measured VSWR is < 2 over 5.725–5.875 GHz frequency band. The proposed antenna with 2×2 array of square parasitic patches provides 80% efficiency and SLL of −24 dB with an associated gain of 14.9 dB. The proposed structure can be packaged inside an application platform. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2911–2917, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23835

Palenquero creole (Colombia) presents two syntactic constructions to express the inherent or contractual nature of the relation between two nouns. This distinction is described for the first time in the case of this language, and its genesis is discussed fromh a multicausal approach: linguistic universal, internal tendencies of the target language (Spanish), and in part, some substratic elements of kikongo.; Le créole palenquero de Colombie présente deux constructions syntaxiques pour exprimer la nature inhérente ou contractuelle de la relation entre deux noms. Cette distinction est décrite pour la première fois dans cette langue, et sa genèse est discutée dans une perspective multicausale : universel linguistique, tendances internes de la langue-cible (l'espagnol), et partiellement, éléments d'un substrat kikongo.

The effect of a protecting dielectric superstrate on the resonance of a high Tc superconducting microstrip patch is investigated. The analysis approach is based on the spectral-domain method of moments in conjunction with the complex resistive boundary condition. The complex surface impedance of the superconducting thin film is determined using London’s equation and the two-fluid model of Gorter and Casimir. Numerical results show that the resonant frequency of the high Tc superconducting rectangular patch decreases monotonically with increasing superstrate thickness, the decrease being greater for high permittivity loading.

Kesterite based on Cu2ZnSnS4 composition are considered as promising absorber material for the next generation of photovoltaics due to raw materials abundance and low toxicity. Developing a superstrate architecture using kesterite as an absorber could be the key to a better performance, which allows new ways of engineering the formation of a kesterite thin film. In this work, we study the effects of the sulfurization temperature on the crystallization of kesterite film when is fabricated in a superstrate architecture, and how this affects the performance of a solar cell. We noted that the temperature affects the final composition of the absorber due to cadmium diffusion at 500 ºC from the CdS layer, while the temperature above 530 ºC is essential for a complete Zn incorporation into the crystal structure. The crystallinity is highly affected, and a temperature of 550 ºC is found to be favorable for the crystal growth, and the fabricated device gave improved performance. Impedance spectroscopy measurements suggest the performance enhancement is due to the reduction of defects and an increase of the depletion width in the p-n junction.

Kesterite based on Cu2ZnSnS4 composition are considered as promising absorber material for the next generation of photovoltaics due to raw materials abundance and low toxicity. Developing a superstrate architecture using kesterite as an absorber could be the key to a better performance, which allows new ways of engineering the formation of a kesterite thin film. In this work, we study the effects of the sulfurization temperature on the crystallization of kesterite film when is fabricated in a superstrate architecture, and how this affects the performance of a solar cell. We noted that the temperature affects the final composition of the absorber due to cadmium diffusion at 500 ºC from the CdS layer, while the temperature above 530 ºC is essential for a complete Zn incorporation into the crystal structure. The crystallinity is highly affected, and a temperature of 550 ºC is found to be favorable for the crystal growth, and the fabricated device gave improved performance. Impedance spectroscopy measurements suggest the performance enhancement is due to the reduction of defects and an increase of the depletion width in the p-n junction.