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Abstract

This paper presents an approximate analytical model for estimating the transmission loss (TL) of a finite rectangular plate in the low frequency range, which is based on the modal summation approach (MSA) taking into account the modal radiation impedance and fluid loading. The mode-dependent radiation resistance is calculated using the Rayleigh integral. The fluid loading is taken into account through the natural frequency modified by the added mass. The results are compared with the ones of Statistical Energy Analysis (SEA) coupled with FEM and FEM coupled with BEM. In addition, the effects of the various vibration modes and the fluid loading on TL, and a way for reducing the calculation time are discussed.

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Authors and Affiliations

Myong-Jin Kim
Kyong-Su Won
Chol-Su Ri
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Abstract

The article presents the application of Acoustic Emission (AE) method for detection and registration of partial discharges (PD) generated in medium voltage (MV) cable isolation and MV cable head. The insulation of the high voltage cable is made of a flexible material whose properties are characterised by a high coefficient of attenuation of the acoustic signals. For this reason, the AE method has not been used so far to detect PD in energetic cables. The subjects of the research were the MV cable and the standard T-type cable head. The cable contained defects which were the source of partial discharges. In case of cable head the PD were provoked by thin grounded electrode which was introduced into connector opening. The results of AE measurements are presented in the form of spectrograms. Acoustic Emission was evoked when the applied voltage level reached the value of 7.5 kV for the cable and 4 kV for the cable head. The authors used the acoustic instrumentation of their own design intended for future field use. Obtaining successful results of partial discharges measurements using the acoustic method in the cable insulation makes an original contribution of the presented work.
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Authors and Affiliations

Zbigniew Ranachowski
1
ORCID: ORCID
Krzysztof Wieczorek
2
Przemysław Ranachowski
1
Tomasz Dębowski
1

  1. Institute of Fundamental Technological Research, Polish Academy of Sciences, Warsaw, Poland
  2. Department of Electrical Engineering Fundamentals, Wrocław University of Science and Technology, Wrocław, Poland
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Abstract

The article presents the achievements of professor Aleksandra Cieślikowa in the field of word-formation of proper names. The most important issues concerning the creation of anthroponyms in the Old Polish era selected from monographs and scientific articles are detailed. These issues include the problems of motivation in onomastic word-formation, the onimization process and the way of describing non-derivatized words by word formation and the participation of paradigmatic derivation in the emergence of Old Polish personal names. The views of Aleksandra Cieślikowa regarding Old Polish anthroponymy contributed to the development of onomastic word-formation, an integral part of the grammar of proper names and gave methodological foundations for the description of Old Polish personal names from a synchronic perspective.

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Authors and Affiliations

Maria Biolik
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Abstract

Fieldexperiment with spring rape (Brassica napus var. oleifera f. annua) cultivars Star andLisonne was conductedin the years 1995–1999 at the vicinity of Olsztyn, Poland. The herbicides trifluralin (Triflurotox 250 EC), alachlor + trifluralin (Alatrif 380 EC), metazachlor (Butisan 400 SC) andclopyralid(Lontrel 300) were appliedin spring rape according to recommendations (Zalecenia 1993). The aim of this study was to estimate the effect of the herbicides on glucosinolates content in spring rape seeds. The obtainedresults revealedsignificant effect of meteorological conditions on glucosinolates content. The Star cv. was characterizedby higher level of these compounds in comparison with Lisonne cv. The adequate values were 15.96 μmol g-1 of d.m. and 12.32 μmol g-1 of d.m., respectively. It is evident on the base of the statistical analyses of the obtained results that herbicides modified glucosinolates content in seeds of both cultivars. The level of these compounds was increased as the effect of Triflurotox 250 EC use (data obtainedfrom three years investigations) and Alatrif 380 EC (four years) while Butisan 400 SC activity was unfavourable (four years).

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Authors and Affiliations

Barbara Adomas

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