With the help of an electromagnetic field simulator (i.e., HFSS), the embedding impedance of a 660-GHz waveguide SIS mixer is thoroughly investigated using a lumped-gap-source and de -embedding method. The effects of the junction’s feed-point displacement and chip thickness are examined.

Abstract: The paper deals with an important textile engineering process: the textile sliver drafting process. It is shown that this process can be modelled as a non-linear time delay system with distributed delays. To convert it into a form more suitable for control purposes, this model is linearized and distributed delays are converted into equivalent lumped delay system. An easy to apply meth...

In this paper, a new and simple approach for the vibration control of flexible spacecrafts during the attitude maneuvering is proposed. Our control strategy integrates the command input shaping and Reference Model Variable Structure Output Feedback Control (RMVSOFC) techniques. In this method, the input shaper is implemented outside of the feedback loop to achieve the exact elimination of the r...

A disturbance observer based tracking control algorithm is presented in this paper. The key idea of the proposed method is that the plant nonlinearities and parameter variations can be lumped into a disturbance term. The lumped disturbance signal is estimated based on a plant dynamic observer. A state observer then corrects the disturbance estimation in a two-step design. First, a Lyapunov-base...

This paper introduces a nonlinear reduced-order modelling methodology for finite-element models of structures with slender subcomponents and inertia represented by lumped masses along main load paths. The constructed models have dynamics described by 1-D intrinsic equations of motion, which are further written in modal co-ordinates. This yields finite-dimensional approximations of the system dy...

This study presents a global electromagnetic optimization technique using Taguchi’s method [1] and its applications in microstrip filter designs. Microwave filters are widely used in telecommunication equipments. Although filters built with lumped elements can realize the desired frequency response, it is difficult to control the lumped elements’ properties in the microwave band. Therefore pass...

A number of fixed grid finite element methods were tested on problems involving heat conduction with phase change. Only methods that can deal with arbitrary enthalpytemperature relationships were considered. Comparisons were made of temperature gradient vs enthalpy gradients formulations, lumped vs distributed capacitance, timeaverage vs space-average apparent heat capacity, iterative vs non-it...

This paper presents the modeling of highly nonlinearcircuits using a total-variation-decreasing (TVD) differencescheme developed for the simulation of problems involving shockphenomena. In contrast to the commonly used leapfrog scheme,a second-order accurate TVD method based on the Lax–Wen-droff scheme is applied to one-dimensional nonlinear transientelectromagnetic-wave...

Synthesis algorithm for mixed lumped and distributed element networks is presented. The algorithm is based on transfer scattering matrix factorization The mixed structure is composed of ladder lumped-elements connected with commensurate transmission lines (Unit elements, UEs). Reflection function expression in twovariable is utilized in the algorithm. First, the type of the element that will be...