Measuring the viscoelastic behavior of highly hydrated biological materials is challenging because of their intrinsic softness and labile nature. In these materials, it is difficult to avoid prestress and therefore to establish precise initial stress and strain conditions for lumped parameter estimation using creep or stress-relaxation (SR) tests. We describe a method ( ɛ˙M or epsilon dot metho...

When we control a flexible manipulator based on a dynamic model, we need to estimate the state variables with accuracy. In the case of rigid manipulators, the state variables consist of joint angles and their velocities, which are measured easily by encoders, potentiometers, tachometers, and so on. In the case of flexible manipulators, however, the state variables also include elastic deformati...

Thermodynamic and dynamic analyses of a variable speed reciprocating compressor have been conducted to investigate performance changes and some data related to the reliability problems such as valve velocity, PV value, bearing loci, Sommerfeld number, minimum film thickness etc. The first law of thermodynamics, continuity equations, valve dynamic equations and Helmholtz resonator method were us...

We consider the initial boundary value problem for the homogeneous heat equation, with homogeneous Dirichlet boundary conditions. By the maximum principle the solution is nonnegative for positive time if the initial data are nonnegative. We complement in a number of ways earlier studies of the possible extension of this fact to spatially semidiscrete and fully discrete piecewise linear finite e...

THE MATHEMATICAL MODEL AND NUMERICAL SIMULATION OF THE HEAT PUMP SYSTEM 1. COLLEGE OF APPLIED SCIENCES – SUBOTICA TECH, SERBIA 2. BUDAPEST UNIVERSITY OF TECHNOLOGY AND ECONOMICS, HUNGARY ABSTRACT: In this paper water-water heat pump is analyzed using a computer simulation. The simulation program is based upon steady state mathematical models of the refrigeration system components. The numerical...

Abstracf—Some current trends in automated network design optfilzation which, it is believed, will play a significant role in the computer-aided design of lumped-distributed and microwave networks are reviewed and discussed. In particular, the adjoint network approach due to Director and Rohrer for evaluating the gradient vector of suitable objective functions related to network responses that a...

This paper presents a formal method of species lumping that can be applied automatically to intermediate compounds within detailed and complex tropospheric chemical reaction schemes. The method is based on grouping species with reference to their chemical lifetimes and reactivity structures. A method for determining the forward and reverse transformations between individual and lumped compounds...

micro-sized in-flight droplets. The unsteady heat transfer process between the in-flight droplets and the ambient air is also analyzed theoretically by using a lumped capacitance method to predict the temperature changes of the in-flight water droplets along their flight trajectories. The measured temperature data are compared with the theoretical analysis results quantitatively, and the discre...

Dynamic transfer functions based on four pole arguments are formulated for a typical discharge system. Various models, such as a lumped Helmholtz model, a one dimensional wave motion model and a three dimensional fmite element model are discussed. An iterating method that couples the time domain calculations of port flow to the frequency domain transfer functions is applied to predict pressure ...

This paper presents complete behavioral analysis of a surface micro-machined MEMS varactor for frequency tuning application in voltage controlled oscillators in RF applications with high Quality factor and tunability. The dimensions of the MEMS device have been optimized with Finite Element Method based CoventorWare analysis and verified through lumped parameter analysis in Saber platform. The ...