A Note on Currents on a Quadratic Surface

Although no explicit general solution is known for the vector integral equation satisfied by the current density vector on a conducting surface, it is shown in the following report that the vector equation can be "scalarized" in the case of a quadratic conducting surface

Transients on a Linear Antenna

[no abstract

Les écoles de l’Alliance israélite universelle et la renaissance de l’hébreu en Eretz Israël

La première école de l’Alliance israélite universelle en Palestine ottomane a été créée à Jaffa en 1864. En raison de multiples obstacles, notamment l’opposition des rabbins orthodoxes contre les études profanes et l’éducation des filles, le réseau scolaire ne fut complètement constitué qu’en 1906. Il comprenait dix écoles primaires de garçons et de filles à Jaffa (puis à Tel-Aviv), Haïfa, Jérusalem, Safed et Tibériade, ainsi que deux écoles professionnelles à Mikveh Israël (1870) et à Jérusalem (1880). Les écoles de l’Alliance ont joué un rôle essentiel dans la renaissance de l’hébreu moderne, grâce à des instituteurs acquis aux méthodes actives, aidés de savants hébraïsants membres d’Hibbat Zion, comme l’ont montré les travaux du regretté Jean-Marie Delmaire sur l’œuvre des pionniers de ce mouvement en Eretz Israël à la fin du XIXe siècle.The first school of the Alliance israélite universelle in Palestine was opened in Jaffa in 1864. Owing to numerous barriers, including the opposition of the orthodox rabbis against the secular studies and the education of girls, the school network was only achieved in 1906. It included ten primary schools of boys and girls in Jaffa (then Tel-Aviv), Haïfa, Jerusalem, Safed and Tiberiade, and two professionnal schools in Mikveh Israel (1870) and Jerusalem (1880). The Alliance schools played a key rôle in the revival of the modern hebrew, thanks to teachers followers of activity-based education and brilliant hebraist scholars members of Hibbath Zion. This study pay tribute to the researches of the late Jean-Marie Delmaire devoted to the work of this pioneer movement in Eretz Israel at the end of the 19th century

Propagation of Electromagnetic Waves Along Corrugated Lines

The propagation of electromagnetic waves along an infinite "corrugated surface" is investigated by means of integral equations and Fourier transform techniques. Results are obtained which take into account the finite distance between the corrugations. In the E case, we obtain in quite a natural way results similar to those previously obtained by R. Hurd

Diffraction of a Trapped Wave by a Semi-Infinite Metallic Sheet

[Figure 1; see abstract in PDF for details]. It is a well-known fact that dielectric coated infinite metallic structures such as planes and wires can propagate "surface modes". We are here chiefly concerned with a two-dimensional case. There is no theoretical difficulty in extending our solution to three-dimensional structures. We are dealing here with a grounded dielectric slab of permittivity ε and thickness a. (The case in which the electric wall is replaced by a magnetic one involves only slight modifications.) The half-space over the slab is a dielectric of permittivity 1. E modes and H modes can propagate in the slab. They are the so- called "trapped waves". The number of modes is connected with ε and a. As an example of the treatment of the general case, we shall suppose that a is small enough to propagate only one E mode. Extension to the H case or to the multimode case is obvious. We then suppose (see Fig. 1) that only one mode is propagating, coming from z = +∞. This trapped wave will be diffracted by a semi infinite metallic sheet of zero thickness, which lies on x = d , z < 0. We are mainly interested in reflection and transmission coefficients for the trapped modes, the radiated power, and the far-field pattern

Propagation of Electromagnetic Waves Along Corrugated Lines

The propagation of electromagnetic waves along an infinite "corrugated surface" is investigated by means of integral equations and Fourier transform techniques. Results are obtained which take into account the finite distance between the corrugations. In the E case, we obtain in quite a natural way results similar to those previously obtained by R. Hurd

Diffraction of a Trapped Wave by a Semi-Infinite Metallic Sheet

[Figure 1; see abstract in PDF for details]. It is a well-known fact that dielectric coated infinite metallic structures such as planes and wires can propagate "surface modes". We are here chiefly concerned with a two-dimensional case. There is no theoretical difficulty in extending our solution to three-dimensional structures. We are dealing here with a grounded dielectric slab of permittivity ε and thickness a. (The case in which the electric wall is replaced by a magnetic one involves only slight modifications.) The half-space over the slab is a dielectric of permittivity 1. E modes and H modes can propagate in the slab. They are the so- called "trapped waves". The number of modes is connected with ε and a. As an example of the treatment of the general case, we shall suppose that a is small enough to propagate only one E mode. Extension to the H case or to the multimode case is obvious. We then suppose (see Fig. 1) that only one mode is propagating, coming from z = +∞. This trapped wave will be diffracted by a semi infinite metallic sheet of zero thickness, which lies on x = d , z < 0. We are mainly interested in reflection and transmission coefficients for the trapped modes, the radiated power, and the far-field pattern

Electromagnetic Waves on Corrugated Lines: Propagation Constant Measurements

In a previous report [G. Weill, Propagation of Electromagnetic Waves along Corrugated Lines, ASTIA Document AD 115 049] an approximate formula for the constant of propagation has been derived from an exact integral equation. It is the purpose of this report to check experimentally the accuracy of our formula

Electromagnetic Waves on Corrugated Lines: Propagation Constant Measurements

In a previous report [G. Weill, Propagation of Electromagnetic Waves along Corrugated Lines, ASTIA Document AD 115 049] an approximate formula for the constant of propagation has been derived from an exact integral equation. It is the purpose of this report to check experimentally the accuracy of our formula

Plékhanov, Introduction à l'histoire sociale de la Russie (Collection historique de l'Institut d'études slaves), 1926

Weill Georges. Plékhanov, Introduction à l'histoire sociale de la Russie (Collection historique de l'Institut d'études slaves), 1926. In: Revue d'histoire moderne, tome 1 N°6,1926. pp. 471-472