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Number of results: 54
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Abstract

Dr. Artur Obłuski of the University of Warsaw tells us about research into political, social, and religious transformations in Sudan in the Middle Ages, the present-day importance of archaeological discoveries, and the meaning of the word “UMMA.”
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Abstract

“Isolation would be most unfortunate. We would be doing science in our own company, completely indifferent to what is happening outside our own universe. This would be totally self-destructive and I hope it will never happen,” says Professor Michał Głowiński in an interview with Grzegorz Wołowiec, titled “A Time Unexpected,” a fragment of which is presented below.
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Abstract

The objective of this research paper is to identify the surveying and legal problems occurring as part of the practical implementation of transforming the right of perpetual usufruct into ownership title in the context of the new regulations that have been in force since 1 January 2019. This is a consequence of the Act of 20 July 2018 on the transformation of the right of perpetual usufruct of the land developed for residential purposes into the ownership title to this land. The research problem of this study is the analysis of the real estate subjected to the transformation of the right of perpetual usufruct into the ownership title in the context of the new regulations in force since 1 January 2019. The conducted research has resulted in the identification of the problems related to the interpretation of these new regulations, also in defining the scope of real properties subjected to the transformation, issuing certificates confirming the transformation, and entering the effects of this transformation into land and mortgage registers. These problems may hinder the practical implementation of the transformation process as well as hamper the execution of real estate transactions. In order to illustrate the implementation scale of these new regulations, the author of this research paper has defined the purposes for which the real properties in the selected city were let into perpetual usufruct, the approximate scope of the properties subject to the transformation and the financial consequences of this process.
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Abstract

The radiation of sound waves from partially lined duct is treated by using the mode-matching method in conjunction with the Wiener-Hopf technique. The solution is obtained by modification of the Wiener-Hopf technique and involves an infinite series of unknowns which are determined from an infinite system of linear algebraic equations. Numerical solution of this system is obtained for various values of the problem parameters, whereby the effects of these parameters on the sound diffraction are studied. A perfect agreement is observed when the results of radiated field are compared numerically with a similar work existing in the literature.
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Abstract

Extensive efforts have been made for many years by the power generating industry to replace conventional solid and liquid insulation with synthetic materials. Those measures are aimed at increasing the load capacity, improved fire safety and extending transformer life during exploitation. Modern insulating materials include aramid fibre-based paper and insulating fluids made of synthetic and natural esters. The paper presents research results of the electrostatic charging tendency (ECT) of mixtures of fresh and aged mineral oil Trafo En with synthetic ester Midel 7131 and natural ester Midel 1204. The measurements were taken in a flow-through system using the pipes made of metal, cellulose and aramid paper. The influence of the liquid flow velocity, the type of material of the measuring pipe and the mixture content on the level of the streaming electrification current generation was determined.
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Abstract

The article discusses the problem with modifications of plans of water areas and the forms of their borders which have been inscribed into the history of all city structures related to water. It can be observed that the modifications made in recent decades very often concern the transformations of former industrial sites. Many such structural changes are taking place within signifi cant areas which have fragmented central parts of cities and created voids in the urban fabric. They are being applied to many former shipyards and ports. Research shows that the formation of new connections between land and water in these transformation processes is essential. More frequently, those conversions that are currently being realized change the constructions of wharves and lead to the development of plans drawing new borders between land and water. In these cases water is introduced into land areas and new land surfaces are being created over existing bodies of water. These operations can be considered extremely valuable in achieving the intended eff ects of transformations of post-industrial areas. They are perceived as an excellent possibility to strengthen the relationship between the city structure and water. At the same time they create an opportunity to achieve a high quality of architectural and landscape solutions and the quality of spaces in both social and economic terms.
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Abstract

Gothenburg is the second-largest city in Sweden, capital of Västra Götaland County Region. It is situated on the west coast of Sweden with the port area located along the Göta Älv River. Due to economic restructuring, waterfront redevelopment emerges as an attractive option to boost economic growth of the city. The aim of this paper is to shed light on conditions of the transformation process of two neighboring areas: Frihamnen and Ringön. Publicly initiated and privately executed waterfront redevelopment in Gothenburg transforms industrial grounds into residential and service oriented areas in Eriksberg, Lindholmen and Frihamnen. The collaborative process of a “developer dialogue” crafts a redevelopment in a consistent way with taking into consideration city’s long-term planning strategy, specifi c needs and opportunities of the neighbourhoods, but also market and fi nancial realities of development community. Another example is a slow and spontaneous transformation of post-industrial areas in Ringön, where still active small industrial fi rms, services, cultural and artistic initiatives take place in the close proximity to the city centre. Results show the waterfront transformation attracts “developers’ dialogue” giving the opportunity to build a coherence for spatial, environmental and socio-economic development. Yet fragmented redevelopment of brownfi eld areas strengthen polarization between dynamic and carefully planned Frihamnen and spontaneously growing Ringön. This paper contributes to the knowledge on the complexity of urban post-industrial transformation.
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Abstract

In the paper a transformation between two height datums (Kronstadt’60 and Kronstadt’86, the latter being a part of the present National Spatial Reference System in Poland) with the use of geostatistical method – kriging is presented. As the height differences between the two datums reveal visible trend a natural decision is to use the kind of kriging method that takes into account nonstationarity in the average behavior of the spatial process (height differences between the two datums). Hence, two methods were applied: hybrid technique (a method combining Trend Surface Analysis with ordinary kriging on least squares residuals) and universal kriging. The background of the two methods has been presented. The two methods were compared with respect to the prediction capabilities in a process of crossvalidation and additionally they were compared to the results obtained by applying a polynomial regression transformation model. The results obtained within this study prove that the structure hidden in the residual part of the model and used in kriging methods may improve prediction capabilities of the transformation model.
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Abstract

In the submitted study, the author shows that Paul in the propositio (12,1-2) the section of encouragement (12,3-15,13), although he does not use the word syneidēsis directly, but the words used in it refer to him in conjunction with his basic functions and prove in this way how fundamental it is to renew the mind in the right, i.e. salvifically effective, education of Christian conscience. He does so in the encouragement context to make the recipients aware of how important it is to have a renewed mind and conscience in being and continuing to become a Christian in everyday and concrete living as well as practicing faith in Jesus. With propositio, he makes the foundation on which he builds the paraclesical message of the Letter. It clearly states that permanently renewed by the Gospel of God mind, is an absolute condition for an uninterrupted evangelical renewal of conscience. Thus, renewed in this way conscience is the only deity of mercy granted to sinful humanity, which guarantees constant faithfulness to its norms of judgment with God’s justice revealed in Christ, the Son of God, or his absolute righteousness, which is an indispensable condition for achieving eternal salvation.
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Abstract

The subject of this paper is the study of the specificity of the transformation of the urban public spaces of the Western world and the problem of the multi form nature of this phenomenon. The Author uses such concepts as that of the "hybrid" and of "hybridization" borrowed from the field of natural sciences and explains the reasons for their introduction within this specific scope of research in a broad manner.
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Abstract

The current climate warming results in a quick recession of glaciers on the northern slopes and valleys of the Lindströmfjellet-Hĺbergnuten mountain ridge in Nordenskiöld Land. The equilibrium line altitude has risen from c. 500-550 m in 1936 to c.750 m in 2001 and c. 800 m in 2006. The slopes, almost completely glaciated during the Little Ice Age, and even in 1936, have mostly been abandoned by glaciers afterwards. The upper parts of the glaciers undergo a clear retreat diminishing their accumulative (firn) fields. The lower parts of the active glacial tongues have been transformed into marginal zones built of dead ice covered with morainic and glacifluvial deposits. The surfaces of the marginal zones are progressively lowered due to ablation of dead ice. The state of the described glaciers is not balanced under the current climatic conditions. Thus, the landscape transformation of the mountain ridge will most certainly continue.
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Abstract

Within this article a large scope of issues associated with development conditions and specifics of shaping the new image of Gdańsk waterfront was presented. The special attention was paid to its part situated within its central zone, located within the city centre. This area was playing a key role in development of the city, as within its boundaries many activities associated with shipbuilding and port industry were located. One has to mention that the Granary Island – a place located in the heart of the waterfront area – was an area of special interest for the port and shipbuilding activities, which relates also to the embankments of both Old and New Motława rivers. But the technological changes in the maritime transportation as well as wart-time destruction of the city decided about the major changes in structure of this area and shifting the port and shipbuilding operations to other sites located to the north from the city centre. Therefore, starting from the year 1945, one could observe the on-going discussion regarding the future of this area, although only in 1990-ties it was possible to actually start implementation of these ideas. At the same time – along with appearance of the demand for the types of apartments, offi ce and commercial spaces that are located on the waterfront – the urban space of Gdańsk waterfront has become interesting for both municipal authorities and developers. In result, a large amount of projects have already been implemented or planned, which contributes towards creation of the new, waterfront urban district of Gdańsk. Within its structure one can distinguish a number of particular sites, including ones still awaiting for their development chances. In the text of this article there were presented the most important parts of these plans, as well as future development directions of urban waterfront structures.
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Abstract

In accordance with the principles of conducting revitalization activities specified in the Revitalization Act in force from 9 October 2015 and horizontal guidelines for revitalization in operational programs for 2014-2020, the preparatory phase of the revitalization process should include multi-layered analyzes concluded with deductions included in communal urban regeneration programs. The article describes the role of student architectural and urban competitions performed in cooperation between municipalities and universities as innovative analytical and conceptual activities that could form the basis for specifying recommendations in revitalization strategies planned by a given municipality. The infl uence of the student competitions’ results on the development of the city revitalization strategy is presented on grounds of periodic competitions organized at the Faculty of Architecture of the Gdańsk University of Technology in cooperation with the Department of Plans and Marketing of the City Hall of the City of Gdańsk.
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Abstract

The paper proposes a methodology useful in verification of results of dilatometric tests aimed at determination of temperatures defining the start and the end of eutectoid transformation in the course of ductile cast iron cooling, based on quenching techniques and metallographic examination. For an industrial melt of ductile cast iron, the effect of the rate of cooling after austenitization at temperature 900°C carried out for 30 minutes on temperatures TAr1 start and TAr1 end was determined. The heating rates applied in the study were the same as the cooling rates and equaled 30, 60, 90, 150, and 300°C/h. It has been found that with increasing cooling rate, values of temperatures TAr1 start and TAr1 end decrease by several dozen degrees.
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Abstract

Paper deals with examinations of properties of shape memory alloy actuators. Authors describe design of own laboratory stand for obtaining electro-thermo-mechanical characteristics of SMA wires (maximum length 900 mm). The stand allows for semi-automatic measurements of voltage and current (supplying the actuator), temperature of wire and its extension. Data acquisition and control signals are realized by PC computer. All elements of the measuring system are connected by GPIB network (IEEE 488.2 standard). Control program for static measurements was written in G language (LabVIEW environment). Temperature is measured using infrared camera Flir A325. Displacement measurement system contains optical sensor (converting piston movement into series of pulses), pulses counter, PWM signal generator (PWM signal fulfillment is proportional to number of pulses), lowpass filter and buffer conditioning external signal. For dynamic measurements data recording is performed using digital oscilloscope Tektronix MSO 2024 equipped with four separated channels and digital filter. Wide range of examinations of several SMA wires allowed for drawing its exploitative characteristic helpful for practical use. It shows length change of actuator as a function of mechanical load (Fig. 10). Finally some example static as well as dynamic characteristics are presented and short discussion is carried out.
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Abstract

In this article I make a critical analysis of educational policy in Poland during the 25 years of the political transformation. I try to refer to the Polish thoughts and practices of teaching experience in the period of 1989–2014. What is more, I present experiences of anti-socialist opposition during the socialist period. They influenced on impression in the works and commitments of many scientists and a new generation of academics. Furthermore, I indicate how my generation after 1989 went into the road of scientific autonomy and / or independence in the field of government and private education. Benchmark for these analyzes build up the hopes which we tied up with the Polish revolution of non- violence. Moreover, there was a strong disappointment, which revealed over the years due to the departure of distinctive political formation of the Third Republic of the ideals and the phenomenon of Polish „Solidarity” movement, and civil society, which included the move away from the base of participatory democracy. Finally, I look at how education as a science and practice of education fit into democratization of the Polish state and society. The key meaning for me has the perception of education as a common good, as environments and entities, institutions or management practices which participate in the democratic society. To sum up, this society is constantly in the period of recovery from years of experience not only fascist, but Bolshevik totalitarianism, too.
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Abstract

Landscape changes of the Gåsbreen glacier and its vicinity since 1899 are described. Maps at 1:50 000 scale of changes of the glacier's elevation and extent for the periods 1938-1961, 1961-1990, 1990-2010, and 1938-2010 are analyzed in comparison with results of the authors' field work in the summer seasons 1983, 1984, 2000, 2005 and 2008. During all the 20th century, the progressive recession of the glacier revealed in a dramatic decrease in the thickness of its lower part, with a small reduction of its area and length. However, further shrinkage produced significant shortening and reduction in area which resulted in final decline of the Goësvatnet glacial dammed lake in 2002. Hence, the lowest (and very thick, up to 150-160 m) part of the former glacier tongue and dammed lake were transformed into a new terraced river valley south of the glacier and a typical marginal zone with glacial landforms north of the glacier. Since 1961, the equilibrium line altitude of the Gåsbreen glacier has risen from ca 350 to ca 500 m a.s.l. and now is located below the very steep rocky walls of the Mehesten mountain ridge, 1378 m a.s.l. Hence, the glacier is being fed by snow avalanches from these rocky walls and much more snow melts during the warmer summer seasons, stimulating a quicker recession of the lowest part of the glacier. This recession may be stopped only by significant climate cooling or increase in snow.
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Abstract

Shape memory alloys are characterised by interesting properties, i.e. shape memory effect and pseudoelasticity, which enable their increasing application. Thermomechanical aspects of martensitic and reverse transformations in TiNi shape memory alloy subjected to tension tests were investigated. The stress-strain characteristics obtained during the tests were completed by the temperature characteristics. The temperature changes were calculated on the basis of thermograms determined by an infrared camera. Taking advantages from the infrared technique, the temperature distributions on the specimen’s surface were found. Heterogeneous temperature distributions, related to the nucleation and development of the new martensite phase, were registered and analysed. A significant temperature increase, up to 30 K, was registered during the martensitic transformation. The similar effects of the heterogeneous temperature distribution were observed during unloading, while the reverse transformation, martensite into austenite took place, accompanied by significant temperature decrease.
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Abstract

Cu-Al-based high temperature shape memory alloys are preferred commonly due to their cheap costs and shape memory properties. In recent years, studies have been conducted on developing and producing a new type of Cu-Al based shape memory alloy. In this study, the CuAl-Cr alloy system, which has never been produced before, is investigated. After production, the SEMEDX measurements were made in order to determine the phases in the Cu84–xAl12Crx+4 (x = 0, 4, 6) (weight %) alloy system; and precipitate phases together with martensite phases were detected in the alloys. The confirmations of these phases were made via x-ray measurements. The same phases were observed by XRD diffractogram of the alloys as well. The values of transformation temperature of alloys were determined with Differential Scanning Calorimetry (DSC) at 20°C/min heating rate. According to the DSC results, the transformation temperature of the alloys varies between 320°C and 350°C. This reveals that the alloys show high temperature shape memory characteristics.
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Abstract

The aim of the performed experiments was to determine the influence of deformation and of austenitization temperature on the kinetics of phase transformations during cooling of high-carbon steel (0.728 wt. % C). The CCT and DCCT diagrams for austenitization temperature 940°C and DCCT diagram for austenitization temperature 1000°C were constructed with the use of dilatometric tests. On the basis of obtained results, a featureless effect of austenitization temperature and deformation on the kinetics of phase transformations during cooling of investigated steel was observed. Critical cooling rates for the transformation of martensite in microstructure fluctuated from 5 to 7°C · s–1 (depending on the parameters of austenitization and deformation), but only at cooling rates higher than 8°C · s–1 a dominant share of martensite was observed in the investigated steel, which resulted in the significant increase of hardness.
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Abstract

This work presents the qualitative and quantitative changes in the products of isothermal transformation (reaction) in a ductile cast iron austenite after supercooling to the temperature range Ar1. The austenitizing temperature considered in this work was 900, 960 or 1020°C. The eutectoid reaction was investigated by metallographic examination at a holding temperature right below Ar11 (820°C) or right below Ar12 (760°C). The quantitative metallographic examination was carried out with a light microscope (LM). The initial transformation stage products were identified with a transmission electron microscope (TEM). The selected samples were studied for chemical microsegregation of manganese, silicon, phosphorus, and carbon with an X-ray microanalyser (MAR). The tested cast iron material was found to predominantly feature a eutectoid reaction in the metastable system the ratio of which was increasing with the austenitizing temperature. The austenitizing temperature was found to be conducive to the evolution kinetics of individual phases and to the graphitization kinetics of the eutectoid cementite that was formed during the contemplated reaction.
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Abstract

Determined was quantitative effect of nickel equivalent value on austenite decomposition degree during cooling-down castings of Ni-MnCu cast iron. Chemical composition of the alloy was 1.8 to 5.0 % C, 1.3 to 3.0 % Si, 3.1 to 7.7 % Ni, 0.4 to 6.3 % Mn, 0.1 to 4.9 % Cu, 0.14 to 0.16 % P and 0.03 to 0.04 % S. Analysed were castings with representative wall thickness 10, 15 and 20 mm. Scope of the examination comprised chemical analysis (including WDS), microscopic observations (optical and scanning microscopy, image analyser), as well as Brinell hardness and HV microhardness measurements of structural components.
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