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Pogrebov V.B., Chernova N.V., Galaktionov K.V., Gavrilo M.V., Kiyko O.A. Barents Sea and Kola Bay: seasonal distinctions in ecological sensitivity to the oil spills by general biological characteristics // Arctic Geology, Hydrocarbon Resources and Environmental Challenges: NGF Abstracts and Proce...more
Environmental sensitivity of the Kola Bay and adjacent areas of the Barents Sea to the oil spills is discussed.
ABSTRACT The developed principles of optimization of the molecular structure and the mixture composition of smectic C* ferroelectric liquid crystal (FLC) are discussed, which significantly allow us to increase the speed of the... more
ABSTRACT The developed principles of optimization of the molecular structure and the mixture composition of smectic C* ferroelectric liquid crystal (FLC) are discussed, which significantly allow us to increase the speed of the electro-optic response in planar alignment of FLS. The achieved results reveal opportunity of construction of fast spatial light modulators with multiplexing owing to bistability with the time of electrical addressing about 1 microsecond(s) .
... a Department of Ichthyology, California Academy of Sciences, 875 Howard Street, San Francisco, California 94103 USA; ptstephens@alaska.com. ... 1, St. Petersburg, 199034 Russia. d Point Stephens Research, PO Box 210307, Auke Bay,... more
... a Department of Ichthyology, California Academy of Sciences, 875 Howard Street, San Francisco, California 94103 USA; ptstephens@alaska.com. ... 1, St. Petersburg, 199034 Russia. d Point Stephens Research, PO Box 210307, Auke Bay, Alaska 99821 USA. ...
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ABSTRACT Two new species of Liparidae (snailfish) Paraliparis macrocephalus sp. nov. and P. rossi sp. nov., captured in the south-western Ross Sea, Antarctica (74–75° S; 165–171° E), are described and illustrated. Paraliparis... more
ABSTRACT Two new species of Liparidae (snailfish) Paraliparis macrocephalus sp. nov. and P. rossi sp. nov., captured in the south-western Ross Sea, Antarctica (74–75° S; 165–171° E), are described and illustrated. Paraliparis macrocephalus resembles, but is distinct from P. hubbsi, P. valentinae, P. somovi and P. aspersus. Paraliparis rossi is similar to P. macrocephalus in meristic counts, pectoral girdle structure and morphometry but differs in size of cephalic pores and nostril, shape of teeth, colour and other characters. Paraliparis macrocephalus was captured in the deepest locality in the Ross Sea, the Drygalski Trough, a 1200 m deep inner-shelf depression. As trawling was preceded by video camera tows, a description of the substratum and fauna of these little-studied trough habitats is also provided.
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Composition and distribution of megabenthic communities around Svalbard were investigated in June/July 1991 with 20 Agassiz trawl and 5 bottom trawl hauls in depths between 100 and 2100 m. About 370 species, ranging from sponges to fish,... more
Composition and distribution of megabenthic communities around Svalbard were investigated in June/July 1991 with 20 Agassiz trawl and 5 bottom trawl hauls in depths between 100 and 2100 m. About 370 species, ranging from sponges to fish, were identified in the catches. Species numbers per station ranged from 21 to 86. Brittle stars, such asOphiacantha bidentata, Ophiura sarsi andOphiocten sericeum,
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We present an example of a single-server polling system with two queues and an adaptive service policy where the stability region depends on the expected values of all the primitives and also on a certain exponential moment of the... more
We present an example of a single-server polling system with two queues and an adaptive service policy where the stability region depends on the expected values of all the primitives and also on a certain exponential moment of the service-time distribution in one of the queues. The latter parameter can not be determined, in general, in terms of any finite number of power moments. It follows that the fluid approximation approach may not be an appropriate tool for the stability study of this model.
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We consider a single-server cyclic polling system with three queues where the server follows an adaptive rule: if it finds one of queues empty in a given cycle, it decides not to visit that queue in the next cycle. In the case of limited... more
We consider a single-server cyclic polling system with three queues where the server follows an adaptive rule: if it finds one of queues empty in a given cycle, it decides not to visit that queue in the next cycle. In the case of limited service policies, we prove stability and instability results under some conditions which are sufficient but not
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This paper deals with the stability study of polling systems with either finite or infinite (countable) number of stations (queues) and with a finite number of servers that poll (visit) the stations along some random (state-independent)... more
This paper deals with the stability study of polling systems with either finite or infinite (countable) number of stations (queues) and with a finite number of servers that poll (visit) the stations along some random (state-independent) routes. First, we formulate "global" and "local" stability theorems for systems with a single server and with a general stationary ergodic input. Their proofs
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We consider a class of polling systems with stationary ergodic input flow such that the control in a system obeys a certain regeneration property. For this class, necessary and sucient conditions for the queue-length process to be bounded... more
We consider a class of polling systems with stationary ergodic input flow such that the control in a system obeys a certain regeneration property. For this class, necessary and sucient conditions for the queue-length process to be bounded in probability are found. Under these conditions, we prove that a stationary regime exists and the queue-length process for a system that
SG Foss and NI Chernova UDC 519.21 w 1. Introduction In this article we consider a polling system with an infinite (countable) number of stations and a single server that polls (visits) the stations along some random route. Customers... more
SG Foss and NI Chernova UDC 519.21 w 1. Introduction In this article we consider a polling system with an infinite (countable) number of stations and a single server that polls (visits) the stations along some random route. Customers arrive at the system in a stationary ergodic (metrically transitive) input. The route of the server enjoys some regenerative property: in the sequence of the server's transitions between the stations and the walking times, it is possible to distinguish independent identically distributed segments which are ...
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Research Interests: Ichthyology and Ecology
ABSTRACT Phenological observations on under-ice swarming behavior of Polar cod Boreogadus saida were performed during the winter period 2009–2010 in the Canadian sector of the Arctic Ocean on the North Pole NP-37 drifting station. These... more
ABSTRACT Phenological observations on under-ice swarming behavior of Polar cod Boreogadus saida were performed during the winter period 2009–2010 in the Canadian sector of the Arctic Ocean on the North Pole NP-37 drifting station. These observations and ichthyologic collections were the basis of the present study. The schools were mostly formed by the immature specimens (TL = 75–169 mm; 1+ to 4+ age), the dominating group was presented by fish of 2+ age (86–94% of total abundance). The driving factors of such large under-ice swarming of Polar cod B. saida in the Arctic are discussed, particularly, the interactions of Polar cod development and the ice drift in the studied region. This species inhabits the overcooled water (−1.8°C) under the ice, so the scheme of the antifreeze agent producing in the fish blood is considered. We make assumptions about under ice migrations of Polar cod swarming.
Research Interests: Ichthyology and Ecology
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This paper deals with the stability study of polling systems with either finite or infinite (countable) number of stations (queues) and with a finite number of servers that poll (visit) the stations along some random (state-independent)... more
This paper deals with the stability study of polling systems with either finite or infinite (countable) number of stations (queues) and with a finite number of servers that poll (visit) the stations along some random (state-independent) routes. First, we formulate ���global��� and ���local��� stability theorems for systems with a single server and with a general stationary ergodic input. Their proofs are based on certain monotone properties of underlying stochastic processes (see [15-17]). Second, we give a stability criterion for systems with ...
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We consider a multi���station queue with a multi���class input process when any station is available for the service of only some (not all) customer classes. Upon arrival, any customer may choose one of its accessible stations according... more
We consider a multi���station queue with a multi���class input process when any station is available for the service of only some (not all) customer classes. Upon arrival, any customer may choose one of its accessible stations according to some state���dependent policy. We obtain simple stability criteria for this model in two particular cases when service rates are either station���or class���independent. Then, we study a two���station queue under general assumptions on service rates. Our proofs are based on the fluid approximation ...