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Number of results: 28
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Abstract

During thirty three expeditions to the Polish Arctowski Antarctic Station signifi− cant influences of human activity upon the environment have been recorded. Introductions of alien species, shifts of bird and seal breeding areas and decreases in both bird and seal populations, are the most obvious effects of human pressure. Though numbers of visits by tourists have increased during this period, impacts from expeditioners appear to be the main cause of changes. In particular, increasing numbers and mobility of summer groups at the station are the likely most influential factors.

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Authors and Affiliations

Katarzyna J. Chwedorzewska
Małgorzata Korczak
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Abstract

It’s difficult to imagine a more curious continent: Antarctica, once very austere and inhospitable, is now becoming greener as a result of climate change.

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Authors and Affiliations

Katarzyna J. Chwedorzewska
Małgorzata Korczak-Abshire
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Abstract

Although he was only recognized as the patron saint of Poland by the Vatican in 2002, St. Andrzej Bobola was accorded a cult following much earlier than this, and venerated as the saint protector of the Polish-Lithuanian Commonwealth. He was seen as a special defender against the threat from first Tsarist Russia, then Orthodox Russia, then the Soviet Union – the Blessed’s intercession was associated with the victory of the Battle of Warsaw in 1920. For this reason, his beatification and canonization were part of political discourse.
Andrzej Bobola’s relics were originally stored in the Jesuit church in Pińsk, moved to Połock after its closure, and were taken to the Hygienic Exhibition in Moscow in 1922. Recovered thanks to the Pope’s intervention in 1924, they were taken to the Il Gesù Church in Rome. By the 1920s, Polish church authorities were already making efforts to canonize Andrzej Bobola and return his relics to Poland. Several Polish cities tried to obtain the saint’s remains, including Vilnius, Warsaw, Pińsk and even Janów Poleski.
The canonization, which took place on 17 April 1938, in particular the ceremonial return of the relics of St. Andrzej Bobola to Warsaw in June 1938, took the form of a great religious and patriotic demonstration. It was accompanied by numerous ceremonies in which the highest church and state authorities participated, with extensive paratheatrical scripts, as well as specially designed decorations and music composed for the occasion. The press reported these in great detail, constituting a fascinating case of an event of both great religious significance and broad political context.
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Authors and Affiliations

Katarzyna Kolendo-Korczak
1

  1. Instytut Sztuki PAN
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Abstract

This paper presents a new type of underactuated ground mobile robot called Caster Car. The platform consists of a front-driven and steered wheel and two uncontrolled rear caster wheels. The Caster Car model presented can be an interesting alternative for mobile robots that connects dynamic properties of hovercrafts and classical 4-wheeled cars. Underactuated properties of the Caster Car cause that classical proportional-derivative feedback control give the ability to affect only selected configuration variables. Three mathematical models of the Caster Car are proposed: a dynamic model with free-moving casters, a dynamic model with blocked casters, and a simplified hovercraft description. Models were tested during tracking tasks with demanding trajectory using selective and full-state control. This full state control was based on the computed torque technique with the pseudoinverse operation and proportional-derivative feedback. It gives the ability to suppress unstable behaviors of uncontrolled orientation but in cost of overall effect (higher position errors).
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Authors and Affiliations

Sebastian Korczak
1
ORCID: ORCID

  1. Warsaw University of Technology, ul. Narbutta84, 02-524 Warsaw, Poland
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Abstract

Open pit mining of rock minerals and the affected areas requiring further development are a serious challenge for shaping the positive image of the mining industry among the public. The direction and method of post-mining land reclamation are important for this image, which should take into account various factors describing the mining area, including social preferences. The article presents an example solution – fuzzy system (FSDR) – which supports the selection of the direction of reclamation of post-mining areas created after the termination of operations of open pit gravel and sand natural aggregate mines. The article presents selected factors determining the selection of the direction and possible reclamation variants as input and output data of the fuzzy system. The rules base of the developed system, as well as the mechanisms of inference and defuzzification, were also characterized. The application of the developed system is presented on selected examples.

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Authors and Affiliations

Jadwiga Król-Korczak
Edyta Brzychczy
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Abstract

How can we make the most of Antarctica's marine resources without damaging the delicate balance of the ecosystem? The answer may lie in an interdisciplinary monitoring system using Unmanned Aerial Vehicles (UAVs) and geoinformatic tools.
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Authors and Affiliations

Anna Zmarz
Małgorzata Korczak-Abshire
Katarzyna J. Chwedorzewska
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Abstract

The order Passeriformes is the most successful group of birds on Earth, however, its representatives are rare visitors beyond the Polar Front zone. Here we report a photo−documented record of an Austral Negrito ( Lessonia rufa ), first known occurrence of this species in the South Shetland Islands and only the second such an observation in the Antarctic region. This record was made at Lions Rump, King George Island, part of the Antarctic Specially Protected Area No. 151 (ASPA 151). There is no direct evidence of how the individual arrived at Lions Rump, but ship assistance cannot be excluded.
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Authors and Affiliations

Piotr Gryz
Małgorzata Korczak-Abshire
Alina Gerlée
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Abstract

A comparison between the levels of infection with Acanthocephala of the fish Notothenia coriiceps in Admiralty Bay (South Shetland Islands, Antarctic) in 1978/79 and 2007/08 is presented. The same eight acanthocephalan species, three echinorhynchids maturing in fish, Aspersentis megarhynchus (dominant species), Metacanthocephalus johnstoni (subdominant species) and M. dalmori (common species), and five polymorphids maturing in mammals and birds, Corynosoma hamanni , C. pseudohamanni (both co−dominant species), C. arctocephali and C. bullosum (both common species), and C. shackletoni (rare species), were found. Echinorhynchids were more numerous in 2007/08 (mean abundance 46.54 versus 35.35 in 1978/79), whereas polymorphids more numerous in 1978/79 (mean abundance 74.35 versus 36.40 in 2007/08). The overall results therefore demonstrated that echinorhynchids were more numerous than polymorphids in 2007/08 and the reverse was true in 1978/79. This situation is dependent mainly upon the decreased infections with C. hamanni , C. pseudohamanni and C. bullosum , and to a lesser degree upon the increasing of infections with M. johnstoni . The decrease of the three Corynosoma spp. is possibly associated with the decreasing of populations of final hosts, seals, on the shore of Admiralty Bay in the vicinity of Arctowski Station.
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Authors and Affiliations

Krzysztof Zdzitowiecki
Zdzisław Laskowski
Małgorzata Korczak-Abshire
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Abstract

The paper summarizes results of twenty years of seabird observations carried out between 1977 and 1996 on the western shore of Admiralty Bay (King George Island, South Shetlands, Antarctic). Changes in population size, distribution and phenology of the breeding species as well as the appearance of non-breeding species are reported. A total of 34 species of birds were observed, including 13 breeding species. Among the non-breeding species, four were observed to visit the site regularly, six rarely, and the remaining 11 were observed only occasionally. Among breeding populations, three Pygoscelis penguin species, the main krill consumers, were most numerous. The Adélie Penguin (P. adeliae) dominated among the penguins nesting in the investigated areas, reaching 23,661 breeding pairs in 1978. Two other penguin species were less abundant with population sizes of approximately 7,200 breeding pairs for the Chinstrap Penguin (P. antarcticus) and 3,100 breeding pairs for the Gentoo Penguin (P. papua) in the same year. During the following two decades, breeding populations of pygoscelid species experienced a declining trend and their numbers were reduced by 68.0% for Chinstrap, 67.1% for Gentoo, and 33.9% for Adélie Penguins. The data reported here represent a unique reference basis and provide valuable information about indicator species, suitable for comparison with contemporary observations of bird populations in the Antarctic Peninsula region, a place of rapidly occurring climate changes and intensive harvesting of marine living resources.
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Authors and Affiliations

Kazimierz Sierakowski
Małgorzata Korczak-Abshire
Piotr Jadwiszczak
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Abstract

Kidney Cooling Jacket (KCJ) preserves the kidney graft, wrapped in the jacket, against the too fast time of temperature rise during the operation of connecting a cooled transplant to the patient’s bloodstream. The efficiency of KCJ depends on the stationarity of the fluid flow and its spatial uniformity. In this paper, the fluid velocity field inside the three different KCJ prototypes has been measured using the 20 MHz ultrasonic Doppler flowmeter. The simplified 2D geometrical model of the prototypes has been presented using COMSOL Multiphysics to simulate the fluid flow assuming the laminar flow model. By comparing the numerical results with experimental data, the simplified 2D model is shown to be accurate enough to predict the flow distribution of the internal fluid velocity field within the KCJ. The discrepancy between the average velocity measured using the 20 MHz Doppler and numerical results was mainly related to the sensitivity of the velocity measurements to a change of the direction of the local fluid flow stream. Flux direction and average velocity were additionally confirmed by using commercial colour Doppler imaging scanner. The current approach showed nearly 90% agreement of the experimental results and numerical simulations. It was important for justifying the use of numerical modelling in designing the baffles distribution (internal walls in the flow space) for obtaining the most spatially uniform field of flow velocity.
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Authors and Affiliations

Barbara Gambin
1
ORCID: ORCID
Ilona Korczak-Cegielska
2
Wojciech Secomski
1
Eleonora Kruglenko
1
Andrzej Nowicki
1

  1. Department of Ultrasound, Institute of Fundamental Technological Research, Polish Academy of Sciences, Warsaw, Poland
  2. Doctoral Studies of Institute of Fundamental Technological Research, Polish Academy of Sciences, Warsaw, Poland
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Abstract

During laboratory and field experiments on Nacella concinna on the west coast of Admiralty Bay, King George Island (Antarctica) clear morphological and behavioural differences between two limpet forms (N. concinna polaris and N. concinna concinna) were found. They suggested presence of genetic divergence. AFLP (amplified fragment length polymorphism) profiling of N. concinna individuals representing the two forms revealed nearly 32% of polymorphic bands; only 2% of them differed between the forms. Our results suggest that the observed phenotypic variation seems to be a result of adaptation to environ− mental conditions and not of any genetic divergence.

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Authors and Affiliations

Katarzyna J. Chwedorzewska
Małgorzata Korczak
Piotr T. Bednarek
Marta Markowska-Potocka
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Abstract

Jak eksploatować morskie zasoby Antarktyki, by nie naruszyć równowagi ekosystemu? Odpowiedzią może być stworzenie warsztatu naukowego do prowadzenia interdyscyplinarnego monitoringu z wykorzystaniem bezzałogowych samolotów i narzędzi geoinformatycznych.
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Authors and Affiliations

Anna Zmarz
Małgorzata Korczak-Abshire
Katarzyna J. Chwedorzewska
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Abstract

The Bulletin of the Polish Academy of Sciences: Technical Sciences (Bull.Pol. Ac.: Tech.) is published bimonthly by the Division IV Engineering Sciences of the Polish Academy of Sciences, since the beginning of the existence of the PAS in 1952. The journal is peer‐reviewed and is published both in printed and electronic form. It is established for the publication of original high quality papers from multidisciplinary Engineering sciences with the following topics preferred: Artificial and Computational Intelligence, Biomedical Engineering and Biotechnology, Civil Engineering, Control, Informatics and Robotics, Electronics, Telecommunication and Optoelectronics, Mechanical and Aeronautical Engineering, Thermodynamics, Material Science and Nanotechnology, Power Systems and Power Electronics.

Journal Metrics: JCR Impact Factor 2018: 1.361, 5 Year Impact Factor: 1.323, SCImago Journal Rank (SJR) 2017: 0.319, Source Normalized Impact per Paper (SNIP) 2017: 1.005, CiteScore 2017: 1.27, The Polish Ministry of Science and Higher Education 2017: 25 points.

Abbreviations/Acronym: Journal citation: Bull. Pol. Ac.: Tech., ISO: Bull. Pol. Acad. Sci.-Tech. Sci., JCR Abbrev: B POL ACAD SCI-TECH Acronym in the Editorial System: BPASTS.

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Authors and Affiliations

Katarzyna J. Chwedorzewska
Małgorzata Korczak-Abshire
Anna Zmarz
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Abstract

Contemporary materials engineering requires the use of materials characterised by high mechanical properties, as these precisely

properties determine the choice of material for parts of machinery and equipment. Owing to these properties it is possible to reduce

the weight and, consequently, the consumption of both material and energy. Trying to meet these expectations, the designers are

increasingly looking for solutions in the application of magnesium alloys as materials offering a very beneficial strength-to-weight ratio.

However, besides alloying elements, the properties are to a great extent shaped by the solidification conditions and related structure.

The process of structure formation depends on the choice of casting method forced by the specific properties of casting or by the specific

intended use of final product. The article presents a comparison of AZ91 magnesium alloys processed by different casting technologies.

A short characteristic was offered for materials processed by the traditional semi-continuous casting process, which uses the solidification

rates comprised in a range of 5 - 20⁰C/s, and for materials made in the process of Rapid Solidification, where the solidification rate can

reach 106 ⁰C/s. As a result of the casting process, a feedstock in the form of billets and thin strips was obtained and was subjected next

to the process of plastic forming. The article presents the results of structural analysis of the final product. The mechanical properties

of the ø7 mm extruded rods were also evaluated and compared.

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Authors and Affiliations

P. Korczak
M. Szymanek
B. Augustyn
D. Kapinos
S. Boczkal
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Abstract

Long term changes (46 years) in the a bundance of pygoscelid penguins breeding populations and nests distribution in the Lions Rump (King George Island) colony were investigated in three time intervals, according to previously published two censuses and one original study conducted in 2010. At that time a detailed colony map based on the GIS system was made. Results of this study showed different trends for each investigated species. In the last three decades Adélie penguin breeding populations showed strong declining tendencies (69.61%). In contrast, the population of gentoo penguins represents the reverse trend, increasing 171.85% over the same period. Observed changes in both penguin population sizes are reflected in the different spatial and geographic distribution of their nests. The population changes observed at the Lions Rump colony are consistent with the relevant pygoscelid penguin tendencies in the western Antarctic Peninsula region. Breeding penguin population dynamics at Lions Rump area with a minimal disturbance by human activity may well illustrate a natural response of those birds to environmental changes in the Antarctic.
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Authors and Affiliations

Małgorzata Korczak-Abshire
Michał Węgrzyn
Piotr J. Angiel
Maja Lisowska
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Abstract

Here we report a photo−documented record of a barn swallow ( Hirundo rustica ) from the South Shetland Islands. We also review previous records of passerine vagrants in the Antarctic (south of the Antarctic Convergence Zone). This barn swallow is the first re− corded member of the Hirundinidae family on King George Island and is only the second passerine recorded in the South Shetland Islands. This sighting, along with previous records of austral negrito and austral trush represent the southernmost sightings of any passerine bird anywhere in the world.
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Authors and Affiliations

Małgorzata Korczak-Abshire
Alexander C. Lees
Agata Jojczyk
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Abstract

The effect of plastic deformation process on the dissolution rate of biocompatible Mg alloys was investigated. Two biocompatible MgLi1Ca0,2Zn1 and MgLi1Ca1Zn1 alloys were selected for the study. The alloys were deformed on a 100T press at a temperature of 350°C by conventional extrusion and by the equal channel angular extrusion process (ECAE). The grain size analysis showed a high degree of the grain refinement from approximately 110 mm in the initial state to 2.8 mm after the 3rd pass of the ECAE process. Compared to as-cast state, the degree of strengthening has increased after plastic forming. The results of biodegradation tests have shown a significant increase in corrosion rate after both conventional extrusion and ECAE, although after subsequent ECAE passes, this rate was observed to slightly decrease in the MgLi1Ca1Zn1 alloy. Based on the results of macro- and microstructure examinations, the corrosion progress in samples after the extrusion process was described.

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Authors and Affiliations

S. Boczkal
M. Karaś
P. Korczak
D. Kapinos
P. Koprowski
W. Szymański
S. Wroński

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