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Abstrakt

Rock excavation is a basic technological operation during tunnelling and drilling roadways in underground mines. Tunnels and roadways in underground mines are driven into a rock mass, which in the particular case of sedimentary rocks, often have a layered structure and complicated tectonics. For this reason, rock strata often have highly differentiated mechanical properties, diverse deposition patterns and varied thicknesses in the cross sections of such headings. In the field of roadheader technology applied to drilling headings, the structure of a rock mass is highly relevant when selecting the appropriate cutting method for the heading face. Decidedly differentiated values of the parameters which describe the mechanical properties of a particular rock layer deposited in the cross section of the drilled tunnel heading will influence the value and character of the load on the cutting system, generated by the cutting process, power demand, efficiency and energy consumption of the cutting process. The article presents a mathematical modelling process for cutting a layered structure rock mass with the transverse head of a boom-type roadheader. The assumption was made that the rock mass being cut consists of a certain number of rock layers with predefined mechanical properties, a specific thickness and deposition pattern. The mathematical model created was executed through a computer programme. It was used for analysing the impact deposition patterns of rock layers with varied mechanical properties, have on the amount of cutting power consumed and load placed on a roadheader cutting system. The article presents an example of the results attained from computer simulations. They indicate that variations in the properties of the rock cut – as cutting heads are moving along the surface of the heading face – may have, apart from multiple other factors, a significant impact on the value of the power consumed by the cutting process.
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The aim of the article is to bring closer a part of the world’s image that is characteristic for the rural community and the richness and variety of the folk culture inscribed in the proprial structures. As a result, this subject requires an integration of different research methods elaborated within the fields of onomastics and dialectology, including linguistic methods of researching a lingual image of the world. The onymic material is as follows: appellative surnames, originating from nicknames formed from dialectal lexemes, surnames motivated by nominal, dialectal hypocorisms, and finally, surnames formed from matronymic phrases (female names), which are an example of an aberrance of the patriarchal family model. Phonetic and formative phenomena should also be focused upon. These are crucial for certain social micro-communities, and are inscribed in the dialectal inflexions of anthroponyms (which function as separate surnames) and marginally in the female surnames with dialectal formants. Onyms with dialectal motivation refer to, and indirectly point, to the contemporary user, the past realities of living in the village community and the lingual and cultural background.
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Abstrakt

Rozwój zarówno miasta jak i gminy Zielona Góra wykazuje postępujący proces niekontrolowanej linearnej rozbudowy tzw. urban sprawl. Zjawisko to, mimo że jest w historii miasta obecne od dawna, wraz z intensywnym rozwojem w XXI wieku, nasila się i wywiera niekorzystny wpływ na jakość zamieszkania, komunikację i dostępność. Przyjęte kierunki zmian zagospodarowania przestrzennego w aktualnych dokumentach strategicznych obszaru nowego miasta (od 1 stycznia 2015) powstałego z połączenia miasta i gminy wiejskiej Zielona Góra nie gwarantują zahamowania niekorzystnych procesów. Skutkiem występowania procesu niekontrolowanej linearnej rozbudowy jest nadmierny i zagęszczony rozrost struktur urbanistycznych wzdłuż dróg i szlaków komunikacyjnych. Uniemożliwia on optymalne wykorzystanie terenów położonych głębiej lub w drugiej linii od istniejącej infrastruktury oraz powoduje powstawanie martwych przestrzeni bez obsługi i dostępu komunikacyjnego. Wraz z każdą nową inwestycją (działka, zgodnie z przepisami, z zapewnionym dostępem do drogi publicznej), dostęp do rozproszonych terenów rekreacyjnych (zieleni), oddala się coraz bardziej od ścisłego centrum miasta. Pogarszające się warunki zamieszkania są bezpośrednią konsekwencją niekorzystnego zjawiska sprawl.
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Ilość aktualnie działających szpitali w Polsce szacuje się na ponad 750 (publicznych i prywatnych). Mimo, że projektowanie, realizacja i wyposażenie szpitali jest określone szeregiem aktów prawnych, permanentne problemy finan-sowe publicznej służby zdrowia i niedoinwestowanie powoduje, że nasze szpitale odbiegają od stanu pożądanego i standardu reprezentowanego przez jednostki w krajach wysoko rozwiniętych. Wieloletnia praktyka w projektowaniu i realizacji pozwala na sformułowanie szeregu uwag o najczęściej występujących nieprawidłowościach, wpływających na zwiększenie ryzyka występowania błędów medycznych i zdarzeń niepożądanych.
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In this paper, the authors present a robot for pipe inspection and exploration, which has in its structure a module for the maintenance of a constant pressure force between the robot's wheels and the inside diameter of the pipe. The paper starts with a short introduction about necessity of the presented solution followed by design aspects and finalizing with the test of the developed compliant module.
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The paper presents adaptation problem of lamellar/rod growth of eutectic. The transformation of eutectic microstructure was investigated systematically. A interpretation of the eutectic growth with theory minimum entropy production was presented.
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The paper presents a new numerical model of solidification processes in hypoeutectic alloys. The model combines stochastic elements, such as e.g. random nucleation sites and orientation of dendritic grains, as well as deterministic methods e.g. to compute velocity of dendritic tips and eutectic grains. The model can be used to determine the temperature and the size of structure constituents (of both, the primary solid phase and eutectics) and the arrangement of individual dendritic and eutectic grains in the consecutive stages of solidification. Two eutectic transformation modes, typical to modified and unmodified hypoeutectic alloys, have been included in the model. To achieve this, cellular automata and Voronoi diagrams have been utilized.
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In Part I of this article, two-stage solidification model was presented. In this part we use our model to simulate solidification of the Al 7% Si alloy for two cooling rates and . Simulations have been performed for two eutectic transformation modes, typical for modified and unmodified alloys. Obtained cooling curves are qualitatively consistent with the typical cooling curves for modified and unmodified alloys. Moreover, evolution of cooling-curve characteristics is compared with the analytical model and found to be in close agreement.
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Abstrakt

The academic environment of Wrocław emerged and developed in particularly difficult conditions of the post WWII era. Thanks to continuation of the tradition, experience and contributions of leading scientists from the former Jan Kazimier University of Lwów, it quickly achieved an important, internationally recognized position in particular in mathematics and chemistry. Two different sociological concepts of relations within the scientific community have developed simultaneously: (1) partnership between leaders and research team members, (2) hierarchical structure based on authority of a leader. History proved that both may be effective. Wrocław became a modern center of research management comparable to leading western universities. The general approach based on relationship „between master and a follower” has been replaced by the more effective relatioship „between a school and a follower”. Similarly to the Lwów tradition the Wrocław Scientific Society has played an integrative role in relations among scientists of different disciplines.
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In this study, modification of the AZ91 magnesium alloy surface layer with a CO2 continuous wave operation laser has been taken on. The extent and character of structural changes generated in the surface layer of the material was being assessed on the basis of both macro- and microscopy investigations, and the EDX analysis. Considerable changes in the structure of the AZ91 alloy surface layer and the morphology of phases have been found. The remelting processing was accompanied by a strong refinement of the structure and a more uniform distribution of individual phases. The conducted investigations showed that the remelting zone dimensions are a result of the process parameters, and that they can be controlled by an appropriate combination of basic remelting parameters, i.e. the laser power, the distance from the sample surface, and the scanning rate. The investigations and the obtained results revealed the possibility of an effective modification of the AZ91 magnesium alloy surface layer in the process of remelting carried out with a CO2 laser beam.
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One of the more important elements of spatial information infrastructure is the organisational structure defining the obligations and dependencies between stakeholders that are responsible for the infrastructure. Many SDI practitioners and theoreticians emphasise that its influence on the success or failure of activities undertaken is significantly greater than that of technical aspects. Being aware of the role of the organisational structure in the creating, operating and maintenance of spatial information infrastructure (SII), Polish legislators placed appropriate regulations in the Spatial Information Infrastructure Act, being the transposition of the INSPIRE Directive into Polish Law. The principal spatial information infrastructure stakeholders are discussed in the article and also the scope of cooperation between them. The tasks and relationships between stakeholders are illustrated in UML, in both the use case and the class diagram. Mentioned also are the main problems and obstructions resulting from imprecise legal regulations.
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This article combines a general introduction to the crime fi ction of Walery Przyborowski with a study of the structure of the plot of his novels. The analyses of ten of his novels conclude with a typology of their narrative schemes, shown in the context of certain invariant patterns and the conventions of related literary genres. While the main objective of this study is to outline the structure of crime story and the social issues depicted in Przyborowski’s crime fi ction, it also pays some attention to the ways in which it refl ects his concerns about contemporary life and the condition of Poland under foreign rule. Basically, Przyborowski’s formula is to make use of the staples of the genre – mystery, adventure, romance – and the techniques of the popular novel. Moreover, his novels, like all of the 19th-century crime fi ctions, are clearly indebted to the conventions of the historical novel.
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The Author discusses the present state of Polish geography against the background of the traditional position, and the rapid development taking place after the Second World War. The introduction of new methods and new directions, as well as new organization are considered to have been reflected in the rising international position of Polish geography. Further topics here include the relationship between physical and human geography, the growing de facto separation of these two branches, and the development of several independent sciences rooted in geography but now existing apart from it (like geomorphology, climatology, hydrology, etc. on the physical geography side, with the element of the environment as a subject of study). On the other hand, social economic geography examines the effects of human activity in the environment, thereby synthesizing spatial management and bridging the gap between the earth sciences, the economy and the social sciences. The degradation of environmental resources, explosion of the human population and climate change have all forced geography (and other sciences) to head in the global direction, as well as towards interdisciplinary cooperation, likewise on the level of the world as a whole. If we are to meet the challenges this all entails, we will need to think about creating interdisciplinary problem teams, as well as activating existing organisational structures in science (notably the geographical sciences), with full benefit taken from research centres that run studies on differing spatial scales, in conjunction with international global programmes like the Future Earth. The geography of the future should not be a closed science, but should draw on the knowledge of scholars of various specialisations, seeking environmental solutions that require intervention on both the global and regional scales. Polish geography should participate in this activity, inter alia as part of Future Earth, as a new venture. It can also be regarded as our task to ensure that society is aware of all the above issues.
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Abstrakt

The component of the cause for the emotional state of the person experiencing the emotion is built into the structure of the class of verba sentiendi. Most emotive verbs can be classed as P(x, q) predicates, where q is the position of the propositional argument in which the content qualifying the causal component is expressed. The syntactic characteristics of sentences (conjunctions, prepositions) often do not communicate unequivocally the causal function. This paper demonstrates the existence in languages of contextual syntactic conditions which foster the use of explicit exponents of causality (e.g., Pol. ponieważ / bo // z powodu; Bulg. защото / понеже // поради / заради / по повод), appearing in alteration with the exponents of cohesion typical of the given verb. Also brought to attention is the use in sentence structures of other lexical means serving a similar function, like Pol. wynikający / płynący; Bulg. причинен / предизвикан. In conclusion it is stated that the research which takes into account the semantic structure of the predicate allows for analyzing phenomena that are usually not included in descriptions of case government of verbs.
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Abstrakt

The population structure, seasonal and diel changes in vertical distribution of two siphonophore species, Dimophyes arctica and Pyrostephos vanhoeffeni , in Croker Passage (Antarctic Peninsula) are examined, and compared with the results obtained by other au− thors in various oceanic areas. Zooplankton samples were taken at discrete depth intervals between 0 and 1200 m during day and night shifts, in both summer and winter seasons. Dimophyes arctica was present both in polygastric and eudoxid forms, with the latter being dominant throughout the entire study period. The results obtained demonstrate that Antarctic waters clearly enhance the reproductive ability of this species when compared with specimens from other oceanic regions. Maximum densities of Dimophyes arctica were recorded in December in the 200–400 m depth horizon. However, high concentrations of eudoxids were also recorded at deeper parts of the water column. Pyrostephos vanhoeffeni was, in contrast, most abundant in autumn and winter, and both species were found to proliferate and disperse or sink further down the water column during autumn and winter. Daily vertical migration was observed only during the summer period.
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Abstrakt

The paper presents a solidification sequence of graphite eutectic cells of A and D types, as well as globular and cementite eutectics. The morphology of eutectic cells in cast iron, the equations for their growth and the distances between the graphite precipitations in A and D eutectic types were analyzed. It is observed a critical eutectic growth rate at which one type of eutectic transformed into another. A mathematical formula was derived that combined the maximum degree of undercooling, the cooling rate of cast iron, eutectic cell count and the eutectic growth rate. One type of eutectic structure turned smoothly into the other at a particular transition rate, transformation temperature and transformational eutectic cell count. Inoculation of cast iron increased the number of eutectic cells with flake graphite and the graphite nodule count in ductile iron, while reducing the undercooling. An increase in intensity of inoculation caused a smooth transition from a cementite eutectic structure to a mixture of cementite and D type eutectic structure, then to a mixture of D and A types of eutectics up to the presence of only the A type of eutectic structure. Moreover, the mechanism of inoculation of cast iron was studied.
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During design of the casting products technology, an important issue is a possibility of prediction of mechanical properties resulting from the course of the casting solidification process. Frequently there is a need for relations describing mechanical properties of silumin alloys as a function of phase refinement in a structure and a porosity fraction, and relations describing phase refinement in the structure and the porosity fraction as a function of solidification conditions. The study was conducted on castings of a 22 mm thick plate, made of EN AC-AlSi7Mg0,3 alloy in moulds: of quartz sand, of quartz sand with chill and in permanent moulds. On the basis of cooling curves, values of cooling rate in various casting parts were calculated. The paper also presents results of examination of distance between arms in dendrites of a solid solution α (DASL), precipitations length of silicon in an eutectic (DlSi) and gas-shrinkage porosity (Por) as a function of cooling rate. Statistical relations of DASL, DlSi, Por as a function of cooling rate and statistical multiparameter dependencies describing mechanical properties (tensile strength, yield strength, elongation) of alloy as a function of DASL, DlSi and Por are also presented in the paper.
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The presented work discusses the influence of material of foundry mould on the effect of modification of AlSi11 alloy. For this purpose castings were produced in moulds made of four various materials. Castings of the first type were cast in a metal die, the second ones in the conventional mould of bentonite-bound sand, those of the third type in the sand mould with oil binder, the last ones in a shell mould where phenol-formaldehyde resin was applied as a binder. All the castings were made of AlSi11 alloy modified with strontium. For a purpose of comparison also castings made of the non-modified alloy were produced. The castings were examined with regard to their microstructures. The performed investigations point out that the addition of strontium master alloy results in refining of the alloy structure, particularly of the α-phase, causes some morphological changes in the alloy and the refinement of eutectics. The advantageous influence of modifier on the structure of the examined silumin was observed particularly in the case of alloy cast either in the conventional oil-bound sand mould or in the shell mould. The non-modified alloy cast into a metal die exhibits a structure similar to those of modified alloy solidifying in the other moulds. The improvement in both tensile strength and unit elongation suggests that the modification was carried out correctly. The best mechanical properties were found for the alloy cast in a metal die, both with and without modification treatment.
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Austenitization is the first step of heat treatment preceding the isothermal quenching of ductile iron in austempered ductile iron (ADI) manufacturing. Usually, the starting material for the ADI production is ductile iron with more convenient pearlitic matrix. In this paper we present the results of research concerning the austenitizing of ductile iron with ferritic matrix, where all carbon dissolved in austenite must come from graphite nodules. The scope of research includedcarrying out the process of austenitization at 900o Cusing a variable times ranging from 5 to 240minutes,and then observations of the microstructure of the samples after different austenitizing times. These were supplemented with micro-hardness testing. The research showed that the process of saturating austenite with carbon is limited by the rate of dissolution of carbon from nodular graphite precipitates.
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Metallic foams are materials of which the research is still on-going, with the broad applicability in many different areas (e.g. automotive industry, building industry, medicine, etc.). These metallic materials have specific properties, such as large rigidity at low density, high thermal conductivity, capability to absorb energy, etc. The work is focused on the preparation of these materials using conventional casting technology (infiltration method), which ensures rapid and economically feasible method for production of shaped components. In the experimental part we studied conditions of casting of metallic foams with open pores and irregular cell structure made of ferrous and nonferrous alloys by use of various types of filler material (precursors).
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The method of pressure die casting of composites with AlSi11 alloy matrix reinforced with 10 vol. % of SiC particles and the analysis of the distribution of particles within the matrix is presented. The composite castings were produced at various values of the piston velocity in the second stage of injection, at diverse intensification pressure values, and various injection gate width values. The distribution of particles over the entire cross-section of the tensile specimen is shown. The index of distribution was determined on the basis of particle count in elementary measuring fields. The regression equation describing the change of the considered index was found as a function of the pressure die casting parameters. The conclusion presents an analysis of the obtained results and their interpretation.
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The objective of the paper is to use the model of Complexity Scales and Licensing (Cyran 2003, 2010) to account for the existence of two prosodic types: ‘syllable’ and ‘word’ languages (Auer 1993, Szczepaniak 2007), which roughly correspond to syllable-timed and stress-timed languages. We will postulate that these categories are not primitive and that many of their phonological characteristics can be derived from simpler mechanisms of licensing. It will be also argued that the phenomenon of contrast plays an important role in prosodic typology and may infl uence syllable structure. Languages use more marked syllabic confi gurations in order to optimise contrast expression. We will carry out an analysis on a simple hypothetical language in order to demonstrate the interdependence of syllabic complexity and the contrastive potential of a syllabic unit.
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In paper is presented results of studies concerning ingot of Al with a purity of 99.5% cast with use of stand of horizontal continuous casting. Mainly together with casting velocity was considered influence of electromagnetic stirrer, which was placed in continuous casting mould on refinement of ingots structure and theirs usability to plastic deformation. Effect of structure refinement and usability to plastic deformation obtained by influence of electromagnetic stirring was compared with refinement obtained by use of traditional inoculation, which consists in introducing of additives i.e. Ti and B to metal bath. On the basis of obtained results was affirmed that inoculation realized by electromagnetic stirring in range of continuous casting mould guarantees improvement in structure refinement and usability to rolling of pure Al continuous ingots.
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The two chosen estates, Garnizon and Wiszace Ogrody have evolved during the last decade or so in Gdańsk. Both developed with the idea of balanced functionality and New Urbanism despite very diff erent locations. The aim was to combine apartment buildings with shops, other services, hotels, offi ce buildings and cultural venues. Numerous interesting and inviting public spaces were also high on the agenda. It was intended to create an interesting, multifunctional space, to maximise the use of the space throughout the day, also making it eco friendly by minimising the use of cars. That`s how an interesting, beautifull space impacts the energy. The centrally located Garnizon has been quite successful, whereas the more peripherally placed Wiszące Ogrody has not quite succeeded due to fi nancial restrictions and is mainly a housing estate at the moment. The hope is that it will grow into a similar entity with new development and helped by the new rail link.
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