Conserved laws and dynamical structure of axions coupled to photons

In this work, we carry out a study of the conserved quantities and dynamical structure of the four-dimensional modified axion electrodynamics theory described by the axion-photon coupling. In the first part of the analysis, we employ the covariant phase space method to construct the conserved currents and to derive the Noether charges associated with the gauge symmetry of the theory. We further derive the improved energy–momentum tensor using the Belinfante–Rosenfeld procedure, which leads us to the expressions for the energy, momentum, and energy flux densities. Thereafter, with the help of Faddeev–Jackiw’s Hamiltonian reduction formalism, we obtain the relevant fundamental brackets structure for the dynamic variables and the functional measure for determining the quantum transition amplitude. We also confirm that modified axion electrodynamics has three physical degrees of freedom per space point. Moreover, using this symplectic framework, we yield the gauge transformations and the structure of the constraints directly from the zero-modes of the corresponding pre-symplectic matrix.

A Modification of Gustavsen and Semlyen’s vector fitting algorithm for overestimated model order

Gustavsen and Semlyen’s vector fitting algorithm (VFA) is popular for the determination of the poles and residues of a sampled response function, modeled as a finite order rational function. However, it does not always perform well when the original function is of infinite order and/or the model order is overestimated. This article is concerned with a novel “null-space” modification of the VFA that provides an accurate representation of the original function when the model order is large and when the original VFA performs poorly. The null-space method is parameterized by a single control parameter, L, which can be adjusted to improve accuracy. Comparisons are made with the original VFA and another of Gustavsen’s modifications

A Modification of Gustavsen and Semlyen’s vector fitting algorithm for overestimated model order

Gustavsen and Semlyen’s vector fitting algorithm (VFA) is popular for the determination of the poles and residues of a sampled response function, modeled as a finite order rational function. However, it does not always perform well when the original function is of infinite order and/or the model order is overestimated. This article is concerned with a novel “null-space” modification of the VFA that provides an accurate representation of the original function when the model order is large and when the original VFA performs poorly. The null-space method is parameterized by a single control parameter, L, which can be adjusted to improve accuracy. Comparisons are made with the original VFA and another of Gustavsen’s modifications

Research of Insertion Loss of Polycrystalline CVD Diamond within Range of 40...80 GHz

Insertion loss of polycrystalline CVD diamond within range of40...80 GHz is investigated by free space method. A diamond disk with diameter 56,6 mm and thickness 366 um was provided by GPI RAS. The disk was found to be radio transparent. Usage of diamond lid to seal LTCC package with T/R MMIC inside resulted in radiation loss by 2,9 dB at 60,5 GHz.

The utilization pattern of east flood canal as public open space in urban area

East Flood Canal is one of the manmade waterfront public open spaces in Jakarta which is often visited by residents. The existence of the public open space is very important for society. The purpose of the study is to identify the utilization pattern of public open space on canal banks and analyze the problems related to the utilization of this space. Method used place-centered mapping to identify physical characteristic of public open space and patterns of activity that occur in the study area. The study is conducted in the segment East Flood Canal on Jl. Kolonel Sugiono, Duren Sawit sub-district, East Jakarta. The result is the pattern of utilizing public open space in the four zones in the East Flood Canal segment is linear because the pattern follows the physical setting of pedestrian circulation paths and bicycle lanes. This study suggests both two circulation pathways (pedestrian and bicycle) need to be designed continuously along the canal and equipped with adequate facilities. Improvement of the planning, design, and maintenance of public open space in the segment of canal will have many benefits to increase social interaction, recreational activities, educational communication, and also a concern for the hydrological aspects of the canal.