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Start Over Coverage 211-222

2. Severní Chantové: příspěvek k pastevectví sobů na Polárním Uralu

Creator:
Bahenský , František and Křížová, Markéta
Format:
print
Type:
model:internalpart and TEXT
Language:
Czech
Description:
TheKhants inhabit the area of the western Siberia in the basin of the river Ob and its tributaries, administratively belonging to the Tlumen region. In the two autonomous districts, Khanty-Mansi and Yamal-Nenets, lives the absolute majority of the Khants. The 1979 census estimated their number to 21 000. The Soviet literatuře divides the Khants to three groups; one of them being the Northern Khants - mostly reindeer herders. The oldest account of the Ob-Ugrians - the Khants and the Mansi ~ we find in the Nestor Chronicle. In the western Siberia there existed two types of transport- the dog teams were ušed by the Khants, the reindeer teams by the Samoyedic groups (for example the Nenets). The question of the time when the Northern Khants started the reindeer herding has not been resolvedyet. During the field research realized in theyears 1996, 1997 and 1999 during my stay with the Maksar family I háve studied the problems concerning the reindeers and the contemporary life in the Khanty community after the disintegration of the USSR. The everyday activity in the camp is centered around the reindeer. The camp moves periodically, depending upon the quantity of the pasture for the reindeer. The Khants can be described as „ seasonal pastoralists “ that every year leave from their point of departure, the community of Pitljar, to places chosen in advance, located in a precisely demarcated area, in summer in tundra, in winter in taiga. In summer the moving of the camp takés plače more often, approximately every fourteen days, in winter the Khants move three or four times altogether at the most. For the moving of the camp they use reindeer team and two types of sled, riding and cargo sled.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

3. Three-dimensional numerical study of submerged spatial hydraulic jumps

Creator:
Foda, Ahmed S., Imam, Yehya E., Bazaraa, Abd Allah S. , and Imam, Emad H.
Format:
počítač and online zdroj
Type:
model:article and TEXT
Subject:
abrupt channel expansion, submerged spatial hydraulic jump, asymmetric jump, oscillatory jump, and computational fluid dynamics
Language:
Slovak
Description:
A three-dimensional numerical model was applied to simulate submerged spatial hydraulic jumps (SSHJ) downstream of a symmetric vent that discharges into a wider channel. Simulations were carried out for different aspect ratios of the vent, expansion ratios of vent width to downstream channel width, tailwater depth, and inlet Froude number. Depending on these factors, simulations indicated the formation of steady asymmetric SSHJ, oscillatory asymmetric SSHJ, and steady symmetric SSHJ, consistent with results of previous experimental studies. The model reproduced observed depth downstream of vent, jump length, and velocity profiles along channel centerline for steady symmetric SSHJ. For oscillatory asymmetric SSHJ, simulated oscillation frequencies had Strouhal numbers that varied with expansion ratio and ranged between 0.003 and 0.015. With piers downstream of the vent, oscillatory SSHJ continued to exhibit jet deflections when pier length was relatively short (≲0.2 of jump length) but became steady asymmetric for longer piers.
Rights:
http://creativecommons.org/publicdomain/mark/1.0/ and policy:public