80 research outputs found
Vocal tract acoustic modelling using FEM with specific element
The study was supported by the Czech Science Foundation, Grant No. 19-04477S: “Modelling
and measurements of fluid-structure-acoustic interactions in biomechanics of human voice
production.
Sensitivity analysis of thermodynamical parameters on the thermal bowed rotor using 2D finite element model
CZ.02.1.01/0.0/0.0/16_019/0000826, SGS19/157/OHK2/3T/1
Observation and modeling of energetic particles at synchronous orbit on July 29, 1977
In the twelve hours following a worldwide storm, there was a series of at least four magnetospheric substorms, the last and largest of which exhibited an expansion phase onset at approximately 1200 UT. Data from six spacecraft in three general local time groupings (0300, 0700, and 1300 LT) were examined and vector magnetic field data and energetic electron and ion data from approximately 15 keV to 2 MeV were employed
Working group written presentation: Trapped radiation effects
The results of the Trapped Radiation Effects Panel for the Space Environmental Effects on Materials Workshop are presented. The needs of the space community for new data regarding effects of the space environment on materials, including electronics are listed. A series of questions asked of each of the panels at the workshop are addressed. Areas of research which should be pursued to satisfy the requirements for better knowledge of the environment and better understanding of the effects of the energetic charged particle environment on new materials and advanced electronics technology are suggested
Anthropogenic Space Weather
Anthropogenic effects on the space environment started in the late 19th
century and reached their peak in the 1960s when high-altitude nuclear
explosions were carried out by the USA and the Soviet Union. These explosions
created artificial radiation belts near Earth that resulted in major damages to
several satellites. Another, unexpected impact of the high-altitude nuclear
tests was the electromagnetic pulse (EMP) that can have devastating effects
over a large geographic area (as large as the continental United States). Other
anthropogenic impacts on the space environment include chemical release ex-
periments, high-frequency wave heating of the ionosphere and the interaction of
VLF waves with the radiation belts. This paper reviews the fundamental physical
process behind these phenomena and discusses the observations of their impacts.Comment: 71 pages, 35 figure
Influence of velopharyngeal insufficiency on phonation of Czech vowels
The effects of velopharyngeal insufficiency on acoustic frequency-modal characteristics of human supraglottal spaces are investigated. The finite element model was developed from magnetic resonance images (MRI) of the subject during phonation. The influence of the velopharyngeal insufficiency on phonation of the Czech vowels /A,I,U/ is numerically simulated in time domain. The Liljecrants-Fantś pulse is used for excitation of the acoustic system
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