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Number of results: 597
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Abstract

The paper presents a detailed analysis of the material damaging process due to lowcycle fatigue and subsequent crack growth under thermal shocks and high pressure. Finite Element Method (FEM) model of a high pressure (HP) by-pass valve body and a steam turbine rotor shaft (used in a coal power plant) is presented. The main damaging factor in both cases is fatigue due to cycles of rapid temperature changes. The crack initiation, occurring at a relatively low number of load cycles, depends on alternating or alternating-incremental changes in plastic strains. The crack propagation is determined by the classic fracture mechanics, based on finite element models and the most dangerous case of brittle fracture. This example shows the adaptation of the structure to work in the ultimate conditions of high pressure, thermal shocks and cracking.
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Abstract

This paper describes the spatial differentiation of topoclimatic conditions in the vicinity of the Arctowski Station (King George Island, Antarctica) during the summer season of the 2006/2007. The measurement stations were located in the Point Thomas oasis as well as on the Ecology Glacier and Warszawa Icefield. The paper analyses meteorological elements such as air temperature, air humidity (eight sites) and wind direction and velocity (three sites). Significant topoclimatic diversities resulting from denivelation, exposure, ground properties and local air circulation were recorded in the study area.
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Abstract

The purpose of this analysis is to deal with the first of the conditions for commencement of laytime, i.e. obligation of the vessel to arrive at the agreed destination. The position, prima facie, with regard to berth, dock or port is relatively straightforward, it having been established that the vessel only becomes an arrived ship when it enters the specified berth, dock or port, respectively. In all three cases, in principle, the risk of delay in reaching the specified berth, dock or port is borne by the shipowner. In many cases, the shipowners, for obvious reasons are not prepared to bear such a risk for loss and take appropriate action. In particular, they demand the inclusion, in the charterparty, of a specific clause shifting the risk of such loss. We will deal therein below with one of the most commonly used forms of such a clause namely – “Time lost waiting for a berth clause” against broader picture of current English jurisdiction.
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Abstract

The buoyant hypopycnal flow of brackish water and suspended sediment transport and settling were studied in two sub-polar fjords: the glacial Kongsfjörden and the outwash (non-glacial contact) Adventfjörden, Svalbard . The data presented indicates faster water mixing on the tidal flat in comparison to the englacial runoff, which leads to faster horizontal density gradients decreases in the non-glaciated fjord. The fast settling of particles in the narrow zone of the steep slope at the edge of the tidal flat leads to the removal of 25% of the surface suspended sediment. The rapid settling is due to increasing salinity, decreasing velocity, and flocculation of fine particles. The fast settling of suspended particulate matter (SPM) in the tidal flat area causes sediment redeposition and resuspension followed by sediment transport along the bottom with hyperpycnal flows. This leads to grain sorting in the fjord head. In contrast, at the glacier front, SPM is transported farther into the fjord, where tidal pumping and water mixing lead to the removal of 71% of total SPM. The fjords investigated represent two different sedimentological regimes. In the glaciated Kongsfjörden, the buoyant hypopycnal flow of brackish water is the main sediment transporting factor. In the non-glacial Adventfjörden, hyperpycnal flows transport sediment along the bottom.
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Abstract

An analysis of seismic shocks from the Heer Land and the Nordaustlandet was made (shocks recorded by the Hornsund seismological station). Kinematic models and synthetic seismograms were constructed. A system of horizontal discontinuities located in the upper mantle was assumed. A good agreement between observational data from the seismograms and theoretical results was obtained.
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Abstract

Studies on the thermics, humidity and refreezing rate of two types of periglacial soils of the marine lowlands of the Hornsund area (SW Spitsbergen) were carried out during spring ablation of the snow cover (1.06.—30.06.1987). Structural soil and peat soil (moss community) were chosen. The soils were studied in places almost completely devoid of the snow cover. A considerable differentiation of temperature in vertical profile and of humidity of surface layer in both soils were found. The dynamics of ground water table and the course and depth of spring refreezing of both soils were also different. The differences reflect the different origin of soils and consequently, their different grain-size distribution, physical properties and morphology of both types of soils as well as their water balance.
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Abstract

Research in Hornsund (SW Spitsbergen) aimed to determine time distribution of heat flux in various soils of Arctic periglacial zone in spring and summer. Typical soils were analysed: tundra gleyey cryogenic soil (Pergelic Cryaquent), tundra peaty soil (Pergelic Histosot) and arctic desert soil (Pergelic Cryorthent). Research sites were located in low plains not covered with ice, near a sea, at 7—13 m a.s.l. Heat flux in soils was measured and recorded automatically every 60 s throughout a whole observation period and concurrently at three sites. In spring and summer intensive heat accumulation was observed in all examined soils. Independently on the weather, a cryogenic gleyey soil received greatest heat throughout a day. Environmental conditions have distinct influence on heat resources in soils.
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Abstract

To retain our cultural identity in the modern world and sensibly think about the future, we need to thoroughly study the past,” says Prof. Marek Figlerowicz from the PAS Institute of Bioorganic Chemistry, who leads the project “The Dynasty and Society of Piast-Era Poland in the Light of Integrated Historical, Anthropological, and Genomic Research.”
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Keywords shale gas

Abstract

Shale gas mining is mainly viewed as an industrial and economic issue. But we can also look at it from the scientific perspective. Why should we?
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Abstract

Switched reluctance motors (SRMs) are still under development to maximise their already proven usefulness.Amagnetic circuit of theSRMcan be made of soft magnetic composites (SMCs). The SMCs are composed of iron powder with dielectric and have a lot of advantages in comparison to commonly used electrical steel. The paper deals with the modelling and analysis of theSRMproduced by Emerson Electric Co. forwashing machines. Numerical calculations and modelling were done using the FEMM 4.2 program. Magnetic flux densities and magnetic flux lines were calculated, as well as electromagnetic torque and inductance for changing the position of a stator to a rotor. The obtained results were compared with other measurement results and are quite similar. The developed numerical model will be used for the project of a motor with an SMC magnetic circuit.
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Abstract

Miarą sukcesu rozwojowego współczesnych regionów i zarazem czynnikiem podtrzymującym trwałość tego sukcesu jest przede wszystkim jakość życia mieszkańców. Według definicji Rady Europy (A new strategy for Social Cohesion, 2004, s. 3) spójność społeczna to zdolność terytorialnych społeczności do zapewnienia dobrobytu wszystkim swoim członkom, zmniejszania rozwarstwień społecznych i unikania polaryzacji. W ocenie spójności społecznej regionu dolnośląskiego w przekroju powiatów w latach 2005–2015 uwzględniono zmienne z następujących dziedzin: dochody i aktywność ekonomiczna ludności, warunki mieszkaniowe ludności, dostępność usług i przestrzeni publicznej. Do pomiaru i oceny zmian poziomu spójności społecznej województwa dolnośląskiego w przekroju powiatów w latach 2005–2015 zastosowano odległość GDM1 oraz miernik Theila.
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Abstract

One of the characteristic features of the architectural landscape of the Stalinist era in Poland (post 1949) was the widespread use of standard designs. Initially these were not part of the propaganda of socialist realist architecture. The ideological justification of the use of standard designs as a “reflection of the era in which they arise” only began in 1953. During the following three years, a period in which the slow process of undermining Stalinist dogmas in architecture took place, supplanted by an openly technocratic vision of an industrialized architecture, the problem of standard designs regularly arose in contemporary discourse. One aspect was the growing criticism of the monotony of housing estates erected throughout the country by the state Workers Housing Department. The issue of these typical projects also came up at the National Conference of Architects in March 1956, where severe criticisms of socialist realism were voiced. The criticism arising from the architects’ milieu was heard alongside positive assessments from those close to the construction industry, who saw standard projects as instruments for producing an “architectural background worthy of a socialist society” in the Polish landscape. The adoption of “theses on typification” in 1959 (probably unwittingly repeating the words used by Hermann Muthesius in 1914) by the team of Władysław Gomułka finally terminated this period of intellectual fermentation, administratively imposing the use of standard projects and industrialised building technologies.One of the characteristic features of the architectural landscape of the Stalinist era in Poland (post 1949) was the widespread use of standard designs. Initially these were not part of the propaganda of socialist realist architecture. The ideological justification of the use of standard designs as a “reflection of the era in which they arise” only began in 1953. During the following three years, a period in which the slow process of undermining Stalinist dogmas in architecture took place, supplanted by an openly technocratic vision of an industrialized architecture, the problem of standard designs regularly arose in contemporary discourse. One aspect was the growing criticism of the monotony of housing estates erected throughout the country by the state Workers Housing Department. The issue of these typical projects also came up at the National Conference of Architects in March 1956, where severe criticisms of socialist realism were voiced. The criticism arising from the architects’ milieu was heard alongside positive assessments from those close to the construction industry, who saw standard projects as instruments for producing an “architectural background worthy of a socialist society” in the Polish landscape. The adoption of “theses on typification” in 1959 (probably unwittingly repeating the words used by Hermann Muthesius in 1914) by the team of Władysław Gomułka finally terminated this period of intellectual fermentation, administratively imposing the use of standard projects and industrialised building technologies.
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Abstract

This is attempt at drawing an audial map of Władysław Reymont’s The Vampire, taking into account all kinds of sound effects that create the atmosphere of horror, complicate the relations between characters and provoke a sense of the uncanny in the reader. One of those devices, whose importance is hard to overestimate, is silence (speechlessness). The article analyzes in detail its use in the novel, which is in many ways indebted to the modernist, neo-romantic poetics of Young Poland.
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Abstract

Michal Walicki (1904–1966) studied Art History at the University of Warsaw (1924–1929), where he received his doctorate for his dissertation on the murals in the Chapel of the Holy Trinity in the Castle of Lublin (1418), under the guidance of Prof. Zygmunt Batowski. He worked in the Department of Polish Architecture at the Warsaw Technical University, at the Warsaw School of Fine Arts (later the Academy of Fine Arts), at the National Museum, and the Art History Institute of the Warsaw University. In 1933, his earned his habilitation for his thesis on the stylistic development of panel painting in fifteenth–century Poland. During World War II, he participated in the resistance movement; he was arrested (in 1949) and put in prison. After his release (in 1953), he combined work at the Institute of History of Art at the Warsaw University and the State Institute of Art (later the Institute of Art of the Polish Academy of Sciences). Michał Walicki’s academic activities encompassed a surprisingly wide spectrum of subjects, though his particular field of interest was painting. He had a ‘positivist’ temperament, concerned with a painstaking search for new works of art and the collecting of material, and above all with cataloguing and sharing the collections. In texts written before the war he built a firm foundation for the study of panel painting in fifteenth–century Poland, although his narrow national perspective is now certainly difficult to accept. After his employment at the National Museum in Warsaw, he changed his profile of research, focusing on modern painting (particularly Dutch), but also on the best understood popularization and education through art. After the war, he initiated and coordinated the work on a series of syntheses, setting new standards of quality in Polish academic studies. He belonged to the narrow circle of great humanists who could write about art with passion, in a manner accessible and understandable to all. He developed his own, easily recognizable style, impressionistic in character, well–suited to aesthetic experiences. As an outstanding university lecturer and museum official, he became one of the founders and most important authorities of the Warsaw school of art history, and as a personality had a profound impact on students and friends led by Jan Białostocki. Above all, he instilled in them a broad outlook on matters of art and the importance of publishing in foreign languages.
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Abstract

Selected Legal Regulations and Cultural Aspects of Urban Development. Nowadays, the issue of urban development belongs to key elements of development in general. Urban development is a multifaceted phenomenon (covering economic, social, administrative, promotional, ecological and a number of other aspects). They are too numerous to discuss them in one short article. For this reason this paper is dedicated only to the phenomena regulated by law: physical planning, suburbanization (initially called urban sprawl), monument conservation and – additionally – culture (as a factor influencing the legal regulations). The key hypothesis is that developers are not the only ones to blame for the way the country looks. This hypothesis has generally been corroborated.
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Abstract

Efektywność posłużenia się analogią w nauce zależy od stopnia adekwatności danej analogii. Teza ta jest poddana sprawdzeniu w kontekście analogii, zarówno biologicznych, jak i informatycznych użytych w teorii memów kulturowych, jako podstawy ewolucyjnego rozwoju nauki, czy szerzej kultury. Uwidoczniony w pracy problem z wyróżnieniem kulturowego odpowiednika biologicznego osobnika ma wpływ na rodzaj ewolucji – darwinowski czy lamarckowski.
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Abstract

The article discusses Nicholas Rescher’s metaphilosophical view of orientational pluralism. In his essay Philosophical Disagreement: An Essay towards Orientational Pluralism in Metaphilosophy Rescher explains a substantial difference between philosophy and science—namely, that philosophers—differently than scientists— continuously propose and undermine various solutions to the same old problems. In philosophy it is difficult to find any consensus or convergence of theories. According to Rescher, this pluralism of theoretical positions is caused by holding by philosophers different sets and hierarchies of cognitive values, i.e. methodological orientations. These orientations are chosen in virtue of some practical postulates, they are of axiological, normative, but not strictly theoretical character. Different methodological orientations yield different evaluations of philosophical theses and arguments. This article shows that Rescher’s account does not determine clearly acceptable cognitive values. If there are no clear criteria of evaluation of methodological orientations, then the described view seems to be identical to relativism adopting the everything goes rule. In addition, accepting orientational pluralism it is hard to avoid the conclusion that discussions between various philosophical schools are futile or can be reduced to non-rational persuasion.
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