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Abstract

The current study is dedicated to measuring vowel temporal acoustics (duration, durational difference, and durational ratio) in the medial position of mostly CVCVCV polysyllabic words in Arabic and Japanese, avoiding the asymmetries in vowel position, syllable structure, and coda consonant quantity (singleton versus geminate) observed in previous experiments. Twenty-nine (16 Arabic and 13 Japanese) participants were asked to use a carrier sentence to produce 60 polysyllabic (mainly CVCVCV) items that contrasted in vowel quantity (short versus long) and vowel quality (/a/, /i/, and /u/) at a normal speech rate. The results show that while short and long vowels are durationally distinct within a language, Japanese vowels are clearly longer than Arabic vowels, although the durational difference remains approximately the same between the two languages. The durational ratio of short-to-long vowel presents a new pattern that contrasts with that reported in earlier research. Specifically, Japanese long vowels in the medial position of polysyllabic words are twice as long as their short counterparts, while Arabic long vowels are more than twice as long. This shows that both vowel position and syllable structure must be considered when measuring vowel temporal acoustics or when structuring stimuli for perception experiments.
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Authors and Affiliations

Yahya Aldholmi
1

  1. Department of Linguistics and Translation Studies, King Saud University, Riyadh, Saudi Arabia
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Abstract

In this paper, the microstructural and texture changes in polycrystalline CuZn30 alloy, copper, and AA1050 aluminium alloy have been studied to describe the crystal lattice rotation during shear bands formation. The hat-shaped specimens were deformed using a drop-hammer at the strain rate of 560 s –1. Microstructure evolution was investigated using optical microscopy, whereas texture changes were examined with the use of a scanning electron microscope equipped with the EBSD facility. The microstructural observations were correlated with nanohardness measurements to evaluate the mechanical properties of the sheared regions. The analyses demonstrate the gradual nature of the shear banding process, which can be described as a mechanism of the bands nucleation and then successive growth rather than as an abrupt instability. It was found that regardless of the initial orientation of the grains inside the sheared region, a well-defined tendency of the crystal lattice rotation is observed. This rotation mechanism leads to the formation of specific texture components of the sheared region, different from the one observed in a weakly or non-deformed matrix. During the process of rotation, one of the {111} planes in each grain of the sheared region ‘tends’ to overlap with the plane of maximum shear stresses and one of the <110> or <112> directions align with the shear direction. This allows slip propagation through the boundaries between adjacent grains without apparent change in the shear direction. Finally, in order to trace the rotation path, transforming the matrix texture components into shear band, rotation axis and angles were identified.
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Authors and Affiliations

I. Mania
1
ORCID: ORCID
H. Paul
1
ORCID: ORCID
R. Chulist
1
ORCID: ORCID
P. Petrzak
1
ORCID: ORCID
M. Miszczyk
1
ORCID: ORCID
M. Prażmowski
2
ORCID: ORCID

  1. Polish Academy of Sciences, Institute of Metallurgy and Materials Science, 25 Reymonta Str., 30-059 Krakow, Poland
  2. Opole University of Technology, Faculty of Mechanics, 76 Prószkowska Str., 45-758 Opole, Poland
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Abstract

Three major pre-Quaternary glaciations have been recognised on King George Island. South Shetland Islands (West Antarctica). The oldest is the Melville Glaciation evidence by fossiferous glaciomarine sediments. Presence of numerous belemnites and Cretaceous calcareous nannoplankton suggested at first a late Cretaceous age. However three is an increasing evidence that these Cretaceous fossils are recycled and occur in late Tertiary (?Miocene) strata. Two glaciations separated with an interglacial have been recognised in a thick Pliocene sequence of laves and sediments. The older Polonez Glaciation is represented by continental-type tillites succeeded by glaciomarine sediments with Chlamys anderssoni fauna. Acidic volcanic activity, coarse-clastic sedimentation and subaerial erosion characterise a mid-Pliocene Wesele Interglacial succeeding the Polonez Glaciation. Andesitic laves and lahars cut by glacially eroded valleys with strongly diagenesized tillites represent the youngest, late-Pliocene Legru Glaciation.

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Authors and Affiliations

Krzysztof Birkenmajer
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Abstract

In the summer of 1979, in South Spitsbergen investigations of the extreme temperatures of the ground surface were carried out. The investigations permitted the determination of the magnitude of the extreme temperatures of the ground surface and their relation to the air temperature. The spatial variability of the extreme temperatures of the ground surface was observed.

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Authors and Affiliations

Andrzej Kamiński

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