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Number of results: 91
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Abstract

The distribution of planktonic Ostracoda (Halocyprididae) was studied based on vertically-stratified zooplankton samples collected by hauling 200 p.m - mesh net by day and by night during two austral seasons: summer 1985/1986 and winter 1989, from the 1200 m deep Croker Passage off the Antarctic Peninsula. Seven species of Ostracoda were recorded: Alacia belgicae, Alacia hettacra, Melaconchoecia isocheira, Metaconchoecia skogsbergi, Boroecia antipoda, Disconchoecia aff. elegans and Proceroecia brachyaskos. The first three species, endemic to Antarctic waters, were predominant (about 90%). Generally Ostracoda were most numerous in 600-200 m layer in summer and in 1000-400 m layer in winter. In the investigated area there was a clear contrast between the abundance of Ostracoda during austral summer and scarcity during austral winter.
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Abstract

During SIBEX the acoustically evaluated amount of krill in the Bransfield Strait and Drake Passage was very low with the mean density 3.24 individuals/m2 and 4.29 individuals/m2 accordingly. Any substantial quantities of krill were found North-West from the Elephant Island and North from the King George Island, where the density of krill exceeded 1000 individuals/m2 (about 100 t/nM2]). The total biomass was estimated at 70590 ton in the Bransfield Strait and at 122470 ton in the Drake Passage, which was many times less than during FIBEX 81, especially in the Bransfield Strait.
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Abstract

In the plankton samples collected with a Bongo net besides Euphausia superba the following species of the Euphausiacea were found:. £. frigida, crystallorophias, E. triacantha and T. macrura. The most aboundant and most frequently caught species was T. macrura equally distributed throughout the research area. The species E. frigida also occurred regularly though in much smaller numbers. E. triacantha occurred sporadically, mainly in the western part of the research region, and E. crystallorophias only at two stations in the Bransfield Strait. Some aspects of the biology and ecology of the mentioned above species are presented in this study.
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Abstract

This paper reports on eleven species of hepatics collected on King George Island, South Shetland Islands (6Г50'—62°15'S latitude and 57°30'—59 00'W longitude). A short account of the vegetation of this Antarctic island is provided and the role of liverworts in particular plant communities is discussed. Two species, Hygrolembidium ventrosum (Mitt.) Grolle and Scapania abcordata (Berggr.) S. Arnell are reported for the first time from the Antarctic botanical zone; the latter is recorded for the first time in the Southern Hemisphere and, additionally, this is the first record of the genus Scapania from Antarctica. A detailed description of the habitat of each taxon is given and distribution maps for the eleven species are provided. A key to the eleven species from King George Island is given, and a detailed taxonomic discussion is included for Cephaloziella varians (Gott.) Steph and Lophozia excisa (Dicks.) Dumort. The former is considered to be synonymous with the widespread Arctic species C. arctica Bryhn & Douin ex K. Müll.
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Abstract

In the region of the Admiralty Bay 12 nesting bird species were encountered of a total abundance of 40890 pairs and biomass amounting to about 395000 kg Three penguin species constituted 91.7% in abundance, their biomass constituting 98.7% of the whole community. Densities of abundance and biomass of adult birds in relation to the living area of penguins (i.e. 775 km2) ranged from 32.3 to 121.4 indiv. km-2 and from 115.1 to 4730 kg k m-2.
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Abstract

Within the SIBEX study area greater concentrations of net-phytoplanklon biomass and numbers were found in waters with clearly defined physical characteristics of either Bellingshausen Sea (an area north and west of Anvers Island and northern part of the Bransfield Strait) or Weddell Sea (south eastern entrance to the Bransfield Strait). Low biomass and cell numbers occurred in the southern Drake Passage and in the south central Bransfield Strait, which in the latter case, appears to be a characteristic feature of ihsse waters during the entire phytoplankton growing season. Early summer blooms of Chaetoceros neglectus and C. tortissimum were mainly responsible for high values of phytoplankton biomass. Some diatoms, such as C. socialis were exclusively associated with Weddell Sea water; a replacement of one water type by another in the Bransfield Strait may considerably modify phytoplankton populations which are present there.
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Abstract

This paper reports on 29 species of lichenicolous fungi collected in the Hornsund region and Sørkapp Land area, Spitsbergen. New to science are Hystrix gen. nov., Slellifraga gen. nov., Dactylospora cladoniicola sp. nov., Hystrix peltigericola sp. nov., Stellifraga cladoniicola sp. nov. and Zwackhiomyces macrosporus sp. nov. A further 15 species are new to Svalbard.
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Abstract

The level of sales of a given good depends largely on the distribution network. An analysis of the distribution network allows companies to optimize business activity, which improves the efficiency and profitability of a company’s sales with an immediate effect on profit growth. The so-called spatial analysis is highly useful in this regard. The paper presents an analysis of the network of authorized dealers of the Polish Mining Group for the Opolskie Province. The analysis was done using GIS (SIP) tools. The purpose of the analysis was to present tools that could be used to verify an existing distribution network, to optimize it, or to create a new sales outlet. The prresented tools belong to GIS operations used to process data stored in Spatial Information System resources. These are so-called geoprocessing tools. The article contains several spatial analyses, which results in choosing the optimum location of the distribution point in terms of the defined criteria. The used tools include a spatial intersection and sum. Geocoding and the so-called cartodiagram were also used. The presented analysis can be performed for both the network of authorized retailers within a region, a city or an entire country. The presented tools provide the opportunity to specify the target consumers, areas where they are located and areas of potential consumer concentration. This allows the points of sale in areas with a high probability of finding new customers to be located, which enables the optimal location to be chosen, for example, in terms of access to roads, rail transport, locations of the right area and neighborhood. Spatial analysis tools will also enable the coal company to verify its already existing distribution network.
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Abstract

An analysis of the power system functioning and the behaviors of the energy market participants allows the trends taking place within years to be identified, including these associated with the evolution of the electric energy and power demand profiles. The problems of balancing the peak power demand are of both a short and long term nature, which implies the need for changes in the electricity generation sector. Apart from the existing “silo-type” generation units, the construction of distributed energy sources implemented in the civic formula in the framework of self-sufficient energy communes and energy clusters is becoming increasingly important. Support for these programs is realized both at the legislative level, as well as within dedicated competitions and ministerial activities. The financial support carried out by the National Fund for Environmental Protection and Water Management and the Regional Operational Programs is also noticeable. One of the activities aimed at spreading the idea of clustering was the competition for certified energy clusters, conducted by the Ministry of Energy. The goal of the contest was the promotion and development of the distributed energy sector, which could be used for the improvement of energy security in the local manner and constitute a basis for the knowledge necessary in planning and developing the state’s energy policy. The paper presents a synthetic analysis of the results of the competition for a certified energy cluster from the perspective of planning and operational needs related to the functioning of the power system. Further, the information about the investment plans of new generation capacities, including their breakdown with respect to type, achievable power and costs has been provided. Also, the balancing of the demand for electric energy by own generation within the energy clusters has been characterized for three time perspectives
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Abstract

An investigation of cyanobacterial microflora in the northern, deglaciated part of James Ross Island in the NW part of the Weddell Sea, Antarctica , was conducted during the Antarctic summer season 2005-2006. Five main types of habitats with dominant cyanobacterial assemblages were analyzed (soils, seepages, streams, wetted rocky walls and lakes), and main ecological variables were measured (pH, temperature, intensity of global radiation, conductivity and nutrients), as a background for further ecological and ecophysiological studies. The definable traditional cyanobacterial morphospecies were identified.
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Abstract

The present contribution to lichen−forming and lichenicolous biota of northern− most Billefjörden (Petuniabukta area, central Spitsbergen, Svalbard) contains 40 species of lichens. Four species: Arthonia ligniariella, Candelariella lutella, Ochrolechia upsaliensis, Polyblastia pernigrata are new for the Svalbard Archipelago.
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Abstract

Net phytoplankton was studied in 10 stations situated west of Elephant Island along three transects located in the Scotia Front zone and in 2 stations situated in the eastern Bransfield Strait. Altogether 70 algal taxa were identified. Phytoplankton density and seston biomass were the highest in stations neighbouring the Scotia Front from the south. In the Scotia Front region Corethron criophilum was a dominant species. Phytoplankton community of the region is rather uniform, however the closer comparison of the phytoplankton species composition allowed to distinguish 4 stations groups. This division is concordant with the hydrological one. A different phytoplankton community was recorded in the eastern part of the Bransfield Strait.
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Abstract

Planktonie material was taken in stratified hauls in the water column between King George and Elephant Islands, during the austral spring 1986. The species composition of Copepoda was diversified (abt. 50 taxa). Most frequent and abundant were M. gerlachei, C. acutus, R. gigas, small copepods of the family Pseudocalanidae and Cyclopoida. Interzonal Copepoda did not yet reach the euphotic zone; a comparatively low general copepod abundance and the advanced ontogenetic development in particular populations evidenced for the early spring phase of the planktonie community.
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Abstract

Grimmia andreaeopsis C. Muell., a species described from sterile material from the Chukotka Peninsula, is redescribed and illustrated The species is actually a member of the genus Schistidium. It can be distinguished from its closest relatives, viz. species of S. strictum complex, by the possession of a unique combination of characters: (1) inky black coloration of gametophytes; (2) strongly and asymmetrically keeled, rapidly wide-spreading to squarrose when moist, leaves; (3) cells entirely smooth, very incrassate and strongly nodulose nearly to the base of the lamina: (4) a costa totally smooth or only occasionally slightly roughened on the back below the apex, but never scabrous with conical papillae; (5) leaf margins always entire; (6) peristome teeth bluntly acuminate. Unlike most rupestral species of Schistidium it grows in wet arctic fens. S. holmenianum Steere & Brassard, a species known to be widely distributed in the Nearctic, and Racomitrium depressum Lesq. var. nigricans Kindb., a variety described from Labrador and Hudson Bay. are synonymous with S. andreaeopsis (C. Muell.) Laz. A comparison of S andreaeopsis with the Andean-Subantarctic S. anqustifolium (Mitt.) Herz is made and these species are considered to be closely related, but not conspecific, bipolar counterparts. Also, a comparison with the South Georgian S. urnulaceum (C. Muell.) Bell and the Holarctic species of S. strictum complex, which are characterized by having similar leaf cell patterns, is made. S. andreaeopsis has a circumpolar distribution, mainly within the High Arctic. In addition to the Nearctic, the species is known to occur in Svalbard, North Land, Taymyr Peninsula, Yakutia, Wrangel Island, and on the Chukotka Peninsula.
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Abstract

Water samples were collected at 12 oceanographic stations from six standard depths ranging from 0 to 100 and 150 m. The number of bacteria and concentration of organic components were expressed in adequate units per 1 litre of sea water and in the form of the integrated values for the whole water column under I m2 of sea of organic components were expressed in adequate units per 1 litre of sea water and in the form of the integrated values for the whole water column under 1 m2 of sea surface. Total numbers of bacteria (TC) ranged from 0.16 to 7.31 x 107/1 and 1.74 — 5.67 x 10, 2/m2 saprophytic bacteria (CFU) 0.10 — 46.85 x 103/1 and 0.62 — 27.7x 108/m2. contents of particulate organic carbon (РОС) 0.02 — 0.25 mg/1 and 3.5 — 20.0 g/m2 dissolved organic carbon (DOC) 0.07 — 3.02 mg/1 and 53.5 — 207.9 g/m2, dissolved free amino acids (DFAA) 0 — 1.8965 μmol/1 and 2.7 -151.5 mmol/m2, dissolved combined amino acids (DCAA) 0 2.9366 μmо1/1 and 16.5— 163.5 mmol/m2, particulate combined amino acids (PCAA) 0 — 3.0215 μmо1/1 and 3.7 — 249.0 mmol/m2. Total numbers of bacteria and РОС, DOC and DCAA concentrations, widely differentiated in the investigated area, were on the average much lower than the values obtaine in previous years. The saprophytic bacteria content and DFAA and PCAA concentrations were at a similar level to that in the past years. Higher TC and CFU values were observed in the areas with high concentrations of phytoioplankton to the NW of Anvers I. and around Clarence I.
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Abstract

Phytoplankton sampling from 13 stations situated in Admiralty Bay was carried out in March. April, May, October and November 1983. Wet settling volume of seston, its dry weight, number of cells under 1 m2 , and qualitative composition of phytoplankton were determined. It was found that amount of phytoplankton was decreasing in April and increasing again in November after the winter season. The share of benthic and periphyton species in the qualitative composition of phytoplankton was quite significant, whereas their quantitative share was rather small. 163 taxa of algae were identified in the net phytoplankton; among these 107 taxa were reported for the first time from the Admiralty Bay. Most abundantly met throughout the entire study period were: Corethron criophilum and Thalassiothrix antarctica.
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Abstract

The paper comprises the review of all 23 known valid species along with synonyms and polytomic keys based on morphological features. Mature specimens of 8 species occur in fishes, 4 in birds, 11 in mammals. Each species settles in a definite section of the digestive tract. The structure of a population is dependent upon the time which has passed since the moment of invasion and the intensity of infestation. Acathocephalans can be found in hosts all the year round, but incomplete seasonality of the occurrence of 2 fish parasites has been recorded. Fish parasites show wide specificity in relation to the hosts mentioned while bird and mammal parasites specificity is narrow. The majority of acanthocephalan species have circumpolar distribution but only 3 have been found inside the polar circle and the other 7 are common in the environs of subcontinental archipelagoes. Acanthocephalans do not yield precedence as far as the diversity of species and infestation intensity are concerned in the Antarctic to other groups of parasite helminths. Their great importance results from their mass occurrence in the vertebrates which are the focus of. man's practical interests — fishes, seals and whales.
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Abstract

This paper reports the species of macromycetes collected on King George Island and Livingstone Island (South Shetlands). Brief notes on taxonomy and distribution of the species are added.
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Abstract

The article concerns safety of power supply for the final consumers, especially its two comprising elements, which are generation adequacy and distribution system reliability. Generation adequacy has been defined with Loss of Load Probability (LOLP), Loss of Load Expectation (LOLE) and Energy Not Supplied (ENS) indices. Conclusions from generation adequacy forecast prepared by ENSTO-E for Poland compared with other European countries for the years 2020 and 2025 have been discussed along with the resulting threats. Interruptions in energy supply have been characterised by power discontinuity indicator SAIDI. Finally, a reliability and adequacy analysis have been performed for different scenarios of the Polish power system operation in order to assess possibilities of using distributed generation as a backup power source. Based on a simulation model created using the DIgSILENT Power Factory software, the reliability and adequacy calculations have been performed with the probabilistic non-sequential Monte Carlo method and they are followed by a discussion of the obtained results.
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Abstract

The loss of power and voltage can affect distribution networks that have a significant number of distributed power resources and electric vehicles. The present study focuses on a hybrid method to model multi-objective coordination optimisation problems for dis- tributed power generation and charging and discharging of electric vehicles in a distribution system. An improved simulated annealing based particle swarm optimisation (SAPSO) algorithm is employed to solve the proposed multi-objective optimisation problem with two objective functions including the minimal power loss index and minimal voltage deviation index. The proposed method is simulated on IEEE 33-node distribution systems and IEEE-118 nodes large scale distribution systems to demonstrate the performance and effectiveness of the technique. The simulation results indicate that the power loss and node voltage deviation are significantly reduced via the coordination optimisation of the power of distributed generations and charging and discharging power of electric vehicles.With the methodology supposed in this paper, thousands of EVs can be accessed to the distribution network in a slow charging mode.
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Abstract

The aim of this work was to investigate the influence of distilled water flowrate in two different porousmembrane modules on the size of generated nitrogen nanobubbles. Modules had different diameter and number of membrane tubes inside the module. As bubbles are cut off from the membrane surface by a shear stress induced by the liquid flow, the change in the linear liquid velocity should result in a change of the generated bubble diameter. For both modules, higher flowrate of liquid induced generation of smaller bubbles, which was consistent with our expectations. This effect can help us in generation of bubbles of desired size.
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Abstract

The paper aimed to get the analysis of spatial horizontal distribution of summer phyto-plankton in a small and shallow lake (Głębokie, Western Polesie, CE Poland) in relation to wind conditions occurring during the research period. The study was conducted in 2011 from 5th of July to 5th of September with eight sampling dates between. Water was sampled in the littoral zone from the depth of 0.5 m in four sites situated in different and opposite to one another lake shores. We analyzed the phytoplankton abundance by the way of chlorophyll a determination as well as the community taxonomic structure. Our research revealed that: a) the direction of the wind, which occurred during sampling might have an important role in the horizontal distribution of planktonic algal biomass within the lake; b) the geomorphology of lake surroundings probably mitigated the influence of wind on phytoplankton distribution; c) even weak or mild wind may influence phytoplankton horizontal differentiation.
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Abstract

Pulse electrochemical machining (PECM) provides an economical and e.ective method for machining high strength, heat-resistantmaterials into complex shapes such as turbine blades, die, molds and micro cavities. Pulse Electrochemical Machining involves the application of a voltage pulse at high current density in the anodic dissolution process. Small interelectrode gap, low electrolyte .ow rate, gap state recovery during the pulse o.-times lead to improved machining accuracy and surface .nish when compared with ECM using continuous current. This paper presents a mathematical model for PECM and employs this model in a computer simulation of the PECM process for determination of the thermal limitation and energy consumption in PECM. The experimental results and discussion of the characteristics PECM are presented.
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Abstract

Knowledge of the temperature distribution in subsurface layers of the ground is important in the design, modelling and exploitation of ground heat exchangers. In this work a mathematical model of heat transfer in the ground is presented. The model is based on the solution of the equation of transient heat transfer in a semi-infinite medium. In the boundary condition on the surface of the ground radiation fluxes (short- and long-wave), convective heat flux and evaporative heat flux are taken into account. Based on the developed model, calculations were carried out to determine the impact of climatic conditions and the physical properties of the ground on the parameters of the Carslaw-Jeager equation. Example results of calculated yearly courses of the daily average temperature of the surface of the ground and the amount of particular heat fluxes on the ground surface are presented. The compatibility of ground temperature measurements at different depths with the results obtained from the Carslaw–Jaeger equation is evaluated. It was found that the temperature distribution in the ground and its variability in time can be calculated with good accuracy.
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Abstract

The present paper contains a list of 104 taxa of lichens and lichenicolous fungi, found in the Cape Lions Rump, Site of Special Scientific Interest No. 34 (King George Island, Antarctica), with their distribution and ecological analysis. A provisional vegetation map of the area is also provided. During the field survey the data were collected using the cartogram method in a grid of squares 250 x 250 m. The current abundance and spatial distribution of lichen species provides baseline data for long-term monitoring biological changes.
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