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A Note on the Construction of Synthetic Basis Functions for Antenna Arrays

Construction of synthetic basis functions (SBFs) for analyzing the radiation problems of antenna arrays is discussed. The SBFs of a block are generated from two separate solution spaces, with one space to account for the effect of the feeding voltages, and the other space to account for the responses of the block to incident electromagnetic fields from its environment. Singular value decomposition

Time-Domain Generalized Transition Matrix for Transient Scattering Analysis of Arrays

Time-domain generalized transition matrix (TD-GTM) based on the time-domain integral equations (TDIEs) is implemented in this letter. The TD-GTM is established on the reference Huygens surface that encloses the object, using the impulse responses obtained by the marching-on-in-time (MOT) solutions. The TD-GTM fulfills the domain decomposition of TDIEs naturally and flexibly. It allows us to analyz

Application of Analytical Expressions for Retarded-Time Potentials in Analyzing the Transient Scattering by Dielectric Objects

Application of analytical formulas for the retarded-time potentials in Müller- and PMCHWT-type time-domain integral equations (TDIEs) is presented. The impulsively excited scalar and vector potentials are evaluated in closed form, and the coupling coefficients can be calculated with high accuracy. Examples of transient analysis of the electromagnetic scattering from dielectric objects are provide

Analyzing Electromagnetic Systems on Electrically Large Platform Using a GTM-PO Hybrid Method with Synthetic Basis Functions

A hybrid method of generalized transition matrix (GTM) and physical optics (PO) with synthetic basis functions (SBF) is proposed to analyze electromagnetic systems on electrically large platforms. Based on domain decomposition method (DDM), the proposed approach is to divide the whole problem into a GTM region and a PO region. The GTM algorithm can simulate antennas and scatterers accurately, and

Informing climate models with rapid chamber measurements of forest carbon uptake

Models predicting ecosystem carbon dioxide (CO2) exchange under future climate change rely on relatively few real-world tests of their assumptions and outputs. Here, we demonstrate a rapid and cost-effective method to estimate CO2 exchange from intact vegetation patches under varying atmospheric CO2 concentrations. We find that net ecosystem CO2 uptake (NEE) in a boreal forest rose linearly by 4.7

A modified construction method of synthetic basis functions for phased antenna array

This paper introduces a modified construction method of synthetic basis functions (SBFs) for analyzing the radiation problems of phased antenna arrays. The effect of the feeding sources and the responses of incident electromagnetic fields are two relatively independent solution spaces. Singular value decomposition (SVD) method is used to extract the characteristic modes to the array from the two s

Application of GTM method combined with local-PO algorithm

In this paper, a hybrid method of generalized transition matrix (GTM) and local physical optics (PO) is proposed. The GTM of a scatterer is defined uniquely to describe the relationship between the out-going fields and the incident fields on a specified reference surface. The PO algorithm is applied to obtain current distribution on the electrically large platform. Due to the locality principle, F

New CBCPW‐to‐SIW transition with improved bandwidth

In this article, a novel Ka band conductor‐backed coplanar waveguide to substrate integrated waveguide transition is presented. The new structure integrates the classical current probe transition with asymmetrical stepped impedance transformer to improve the operating bandwidth. An equivalent circuit model is also given, which clearly illustrates the operational principle of this new transition. F

Research on the equivalent model for antenna element based on generalized transition matrix

In this paper a generalized transition matrix method is utilized to analyze the equivalent model for antenna element.The characteristics of antenna element can be extracted from the internal complex structure of the antenna element to an external reference surface through generalized transition matrix and mapping vectors.The generalized transition matrix module contains three parts:a generalized t

Becoming summoned to, visit and exit a “Barnahus” from Child Perspective

The institution ‘Barnahus’ [Children’s House] have been established in the Nordic countries in purpose to improve the investigations and collaboration of involved agencies in protecting children in suspicion of being victims of serious crimes of abuse. Sometimes children visit Barnahus with their parents. In Sweden when custodians or related persons are suspected, children can be summoned to Barna

Security through European integration or flexible autonomy : Ambivalence in Sweden’s position on the Eastern Partnership?

This article explores Sweden’s multiple roles in foreign policy in relation to its actions as an EU member state, seeking also to contribute to the understanding of small-state roles and behaviour at the dawn of a new age of uncertainty in Europe. Based on analytical tools derived from role theory within foreign policy analysis, as well as European integration theory, the article presents an analy

Epigenetic modifications inlysine demethylases associate with survival of early-stage NSCLC

Background: KDMlysine demethylase family members are related to lung cancer clinical outcomes and are potential biomarkers for chemotherapeutics. However, little is known about epigenetic alterations inKDMgenes and their roles in lung cancer survival.Methods: Tumor tissue samples of 1230 early-stage non-small cell lung cancer (NSCLC) patients were collected from the five independent cohorts. The 3

Unbiased Adaptive LASSO parameter estimation for diffusion processes

The adaptive Least Absolute Shrinkage and Selection Operator (aLASSO) method is an algorithm for simultaneous model selection and parameter estimation with oracle properties. In this work we derive an adaptive LASSO type estimator for diffusion driven stochastic differential equation under weak conditions, specifically that the algorithm does not rely on high frequency properties.All conditional m