In this research paper, an innovative approach is employed to design and simulate a Bethe hole coupler utilizing ridge gap waveguide (RGW) technology. The RGW structure includes two parallel metal plates, a ridge, and strategically placed pins. To achieve the coupler structure, we place two waveguides facing each other, and between these two waveguides, there is a perforated metal plate. Initially, four holes are set in the plate between the waveguides to enhance the coupling coefficient's bandwidth. The radius of the holes is initially calculated and designed to achieve a 20 dB coupling. The validity of the design is confirmed using CST software. RGW transition design is usually more difficult than other gap waveguide structures. For this reason, in this paper, a technique called Step Ridge Waveguide Excitation (SRWE) is introduced for efficient excitation of the designed coupler. The proposed methodology is implemented in the Ku band, which is suitable for satellite communication with high bandwidth. The dimensions of our structure are 50mm × 30mm × 17mm. Additionally, a 20±2 dB coupling coefficient is obtained for a fractional bandwidth (FBW) of approximately 29%. It demonstrates a directivity range of 6-16 dB, and the isolation is lower than 23 dB, surpassing the performance of similar previous works.

Design and simulation of high directive waveguide directional couplers based on supershapes are presented, in the present paper. In order to obtain high directivity, circular holes in a conventional coupler are equivalently substituted with supershape holes. In the frequency range from 8 to 12 GHz, the coupling values of two proposed couplers are 19± 1 dB and 23± 2 dB and the directivities are better than 20 dB. The simulation results show that almost 20 dB improvement in the directivity can be achieved as compared to a conventional coupler. The results are valuable for the design and development of broadband high directive waveguide couplers.

We consider Bethe-Salpeter (BS) equation for the bound state of two point particles in the non-commutative space-time. We subsequently explore the BS equation for spin0-spin0, spin1/2 - spin1/2 and spin0 - spin1/2 bound states. 222 we show that the lowest order spin independent correction to energy spectrum in each case is of the order өα4 while the spin dependent one in NC space, is started at the order θα6.  

Single shock in reaction-diffusion models on the Bethe lattice with nearest neighbor interaction is introduced. The evolution equation of the system can be solved through the full interval method in closed form exactly. Comparing the results of analytical and numerical approaches is studies. The stationary and dynamics solution of such models are discussed. It is shown that in the stationary configuration, all sites are occupied.

Charged particles such as protons and carbon ions are an increasing tool in radiation therapy. However, unresolved physical problems prevent optimal performance, including estimating the deposited dose in non-homogeneous tissue, is an essential aspect of optimizing treatment. The Monte Carlo (MC) method can be used to estimate the amount of radiation, but, this powerful computing operation is very expensive, and has the ability to restrict it. In this work, we use basic physics in the form of the Bethe equation to provide a new analytical solution for range, energy and LET of particles. This solution is presented in terms of the functional integral by converting the relativistic harmonics, which allows it to be used at the level of radiotherapy energy (protons 50-350 MeV, carbon ions of 100-600 Mev / a. m. u). The agreement along the path of the particles, with some differences in reaching the path is high. The model presented in an optimization framework for radiation particle radiation is estimated as a rapid method for dose and LET, which is able to account for heterogeneity in electron density and ionization potential.

Let G be a simple connected graph and {v1, v2, v3, …, vk} be the set of pendant (vertices of degree one) vertices of G. The reduced distance matrix of G is a square matrix of order k whose (i, j)-entry is the topological distance between vi and vj of G. A rooted tree is called a generalized Bethe tree if its vertices at the same level have equal degree. In this paper, we compute the spectrum of the reduced distance matrix of the generalized Bethe trees.

Coaxial couplers with high input RF power, usually operated at 500 MHz, are one of the critical components used in accelerators. To withstand high RF power, the couplers should be tested first, under identical conditions in a test stand. A waveguide coupled to a coaxial cable is used for this purpose. The parameter that indicates the amount of returned power loss isS 11 which is reduced by optimizing the dimensions of the proposed model. MATLAB program has special and powerful tools to optimize the dimensions of models simulated in CST STUDIO SUITE. In this paper, the details and processes of how MATLAB can control CST are described using MATLAB. Then, the optimization of coaxial coupler coupling to 1800 waveguide with high input power is carried out.

A method for fabricating optical directional couplers by combining thermal and field assisted ion exchange processes is presented. Modeling, design, fabrication, and test methods are discussed. This method eliminates the need for high-resolution lithography that is needed in conventional methods of coupler fabrication.

In this paper, the effect of surface curvature on calibration coefficients of the hole-Drilling method has been studied. Firstly, an FE simulation of the drilling process has been modeled for a flat surface. Then, the simulation has been implemented on a cylinder with different diameters and the calibration coefficients have been extracted. In all analyses, the stain-gauge rosette and hole diameter remain constant and mesh removal in the drilling simulation was achieved in eight increments. The comparison of simulation results and standard published calibration coefficients data for a flat surface show an acceptable error equal to 2.8 variation of errors between 0.6 to 6.2.