buletinul institutului politehnic din iaşi bulletin of the polytechnic ...

Ansoft. A dc applied magnetic field (3 ÷ 6.5 kOe) was set in order
to obtain the ferromagnetic resonance modification of the material.
By simulations, tunability was achieved in the 12 - 20 GHz
frequency range. The tunable electromagnetic properties of the
YIG films were also studied in ac electromagnetic fields (12 - 30
GHz), on the high-frequency side of the resonance. The fielddriven
response of the labyrinthine magnetic domain walls is
harmonic, determining a similar evolution of the magnetization.
For a manufactured metamaterial including the YIG film and a
metallic grid array, simulated with HFSS, the negative magnetic
permeability was determined in a controlled frequency domain.
This domain was identified as 13 - 20 GHz, depending on the
metamaterial structure and controlled by the dc/ac driving field.
The study is dedicated to the performance optimization of the YIG
devices in microwave range.
Key words: advanced modeling techniques, simulation in
manufacturing systems, optimal design.
EXPERIMENTAL DETERMINATION OF
R a AND R z ON TURNING STEELS
by
ALIN LUCA, MIRCEA COZMÎNCĂ and ANA MARIA MATEI
Abstract. Establishing the roughness of cutting parts is very
important because it affects the functioning of the work pieces. This
influence reflects the operating characteristics of the piece such as
wear resistance, corrosion, the coefficient of friction, the degree of
tightness, etc. Surface roughness is characterized by different
roughness parameters and the most important are the arithmetic
average deviation of the profile R a and ten-point mean roughness
R z . This paper aims to highlight the relationship between R a and R z
by measuring the roughness of specimens subjected to the turning
process.
Key words: cutting, roughness, roughness parameters.
FORCE SENSOR IN A WIM HYDROSTATIC SYSTEM
by