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Number of results: 180
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Abstract

Risks pertaining to construction work relate to situations in which various events may randomly change the duration and cost of the project or worsen its quality. Because of possible significant changes of random events, favorable, moderate, and difficult conditions of construction work are considered. It is the first stage of the construction risk analysis. The probabilistic parameters of construction are identified and described by using the design characteristics model of the structure and the construction technology model. The first describes the probabilistic properties of the structure execution's technology. The second describes the probabilistic properties of the works execution. Both models contain basic probabilistic data for scheduling, cost estimating, and risk assessment of the construction.
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Abstract

The objective of the article is to examine the approximative and adjustive uses of the verb dire, which is mostly regarded as an assertive and eventful verb; hence nonapproximative. Meanwhile, in many expressions, in an impersonal use, in negation when the subjunctive mode is used, in the conditional forms, its evidence value is weakened and the verb dire can express approximation. The study is situated in light of the enunciation theory, notably it refers to a notion of modalisation. The corpus was established on the basis of dictionaries, which are representative for normative uses, but we will refer as well to press texts, particularly interviews, where the verb say is frequently used as a marker of the position of the speaker.
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Abstract

On the basis of 35 one-hour series of the measurement of the wind velocity, read out every two minutes, the wind structure at the Arctowski Station, situated on Admiralty Bay, King George Island, was analysed. Very strong turbulence was found with air flow directions from over the area of the Island (S, SW. W and NW) and laminarity with directions from SE, E, NE and partly N, i.e. when the air flows from Admiralty Bay or from over the open waters of Bransfield Strait. The qustiness coefficient, the relationship between the maximum and mean velocities and the intensity of turbulence were determined for the two flow types. Two extremely different cases, in terms of flow character, were considered, by determining for them the distributions of instantaneous velocities and those of oscillations.
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Abstract

Power spectrum techniques were applied to two time series of wind speed values recorded at the Arctowski Station in order to investigate the influence of turbulent and laminar air flow on the quasi-periodicity of the micro-scale wind structure.
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Abstract

Seismic refraction studies on Central Spitsbergen have shown that there is the fault systems with north-south strike directions, which divide the crust into western, central and eastern blocks. Thickness of the crust in this area varies from 35 to 40 km. Interpretation and modelling of seismic refraction data indicate that the Moho boundary beneath the Central Spitsbergen Basin is a complicated transition zone between crust and upper mantle with the thickness of about 5 km.
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Abstract

The presence of Euphausia superba, E. crystallorophias and Thysanoessa macrura was observed in Admiralty Bay (King George Island, South Shetland Islands) and the size of individuals of particular species are diverse and varying during the summer season. E. superba population is older and specimens larger than in analogous season in 1979. The maximum number of females with eggs was noted in the first half of January 1980, i.e. earlier than in 1979. In E, crystallorophias population the presence of females with eggs was observed in the second half of December 1979.
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Abstract

Considering concrete nonlinearity, the wave height limit between small and large amplitude sloshing is defined based on the Bernoulli equation. Based on Navier-Stokes equations, the mathematical model of large amplitude sloshing is established for a Concrete Rectangle Liquid-Storage Structure (CRLSS). The results show that the seismic response of a CRLSS increases with the increase of seismic intensity. Under different seismic fortification intensities, the change in trend of wave height, wallboard displacement, and stress are the same, but the amplitudes are not. The areas of stress concentration appear mainly at the connections between the wallboards, and the connections between the wallboard and the bottom.
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Abstract

Rocks of the Legoupil Formation in the Cape Legoupil area were folded about a N70E oriented axis. Later these rocks were affected only by brittle deformation which occurred in four stages: (1) jointing — set I, (2) dyking, (3) faulting and, (4) jointing — set II. Both, folding and subsequent brittle deformation, are hardly compatible with the Mesozoic-Cenozoic eastward subduction of the ancient Pacific ocean crust.
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Abstract

The first post-war, comprehensive Gdynia Downtown Plan was at the same time one of the first spatial development plans in Poland defining the directions of transformation of multifunctional downtown structures in the new system and legal realities. It was the Plan of the Polish Breakthrough related to the realities of the downtown area of Gdynia. The study area included the Gdynia Valley limited by the hills of Kamienna Góra, Redłowo and Chylońskie Forests with the development of a complete pre-war city developing in accordance with the fi rst plan of Adam Kuncewicz from 1925 in the zone of 3 km, counted from the center of the inner port. The aim of the plan was to look for centralizing potential in the fi eld of research. This concept was treated as a power degree related to the then existing state, as well as the possibility of further development or transformation.
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Abstract

The protection of Polish architectural heritage in the former eastern borderlands, accomplished through the conservation and technical securing of historical structures, constitutes one of the main programmes that are implemented by the Ministry of Culture and National Heritage. Currently, many Polish historical buildings in the former eastern borderlands are in a very bad technical condition. The load-bearing systems of these elements, as well as elements of their finish, require immediate emergency securing work. The basic steps that precede conservation work are emergency structural works, which guarantee the durability and stability of the entire historical substance. The specifics and complexity of the problem of the failure of historical buildings often demands an in-depth analysis of a series of factors that are difficult to measure and which are responsible for the cause and effect relationship during the early stage of the technical evaluation of a structure. The analyses of failures of numerous historical structures, for instance that were carried out by the authors, have become the inspiration for the search for effective methods of analysis that would allow for an in-depth analysis of the causes and effects of the failures in question. The DEMATEL method (Decision Making Trial and Evaluation Laboratory) that has been presented in this work, and its fuzzy extension, has lately become one of the more popular methods used in the cause-and-effect analysis of various phenomena. The authors demonstrated how this method works on the example of the evaluation and securing of the load-bearing system of the XVII Collegiate church of the Holy Trinity in the town of Olykha in the Volhynskiy Oblast, Ukraine.
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Abstract

Four Geodynamical Expeditions of the Polish Academy of Sciences carried through wide research seismic program in West Antarctica in 1979-1991. Three of these expeditions operated in the Bransfield Strait. The experiment of deep refraction and wide-angle reflection in West Antarctica focused on deep structure of the lithosphere, mainly of the Earth's crust. The network of deep seismic soundings (DSS) profiles covered all the Bransfield Strait. Five land stations on the South Shetland Islands, three stations on the Antarctic Peninsula and nine ocean bottom seismographs (OBS) recorded seismic waves, generated by explosions in a sea. The Bransfield Rift and the Bransfield Platform form a marginal basin against a volcanic arc of the South Shetland Islands. The paper presents new results of 2-D seismic modeling for network of five selected profiles. Four of them, ranging in lenght from 150 to 190 km, crossed main structures of the Bransfield Strait and the fifth, which connected the other ones and was 310 km long, ran along the Bransfield Rift. Two or three seismic models were presented for each profile. Finally, mutually corrected and controlled 2-D models of described profiles were constructed. They all presented spatial complex structure of the Earth's crust in a young rift of the Bransfield Strait, including extent of its main element i.e. anomalous high velocity body (HVB) (Vp > 7.4 km/s), detected in 10-30 km depth range except profile DSS-4 (southwest part of the Bransfield Strait). This inhomogeneity is interpreted as intrusion of the upper mantle (?asthenosphere) during stretching of the continental crust. The Moho discontinuity was found at depth 30-35 km, with velocities equal to about 8.1 km/s.
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Abstract

A gigantic amounts of data and information on molecules that constitute the very complex cell machinery have been collected, classified and stored in data banks. Although we posses enormous amount of knowledge about the properties and functions of thousands of molecular entities, we are still far from understanding how they do work in a living cell. It is clear now that these molecules (genes, proteins) are not autonomous, that there is no direct linear relation between genotype and phenotype, and that the majority of functions are carried and executed by concerted molecular activity, and that the majority of diseases are multifactorial. A basic property of the matter in a living cell (both normal and pathologic) is an interaction between variety of macromolecules, mainly proteins, genes (DNA) etc. In a process of self-organization they are able to form an active molecular biologic system – a complex, labile and dynamic network which integrity is secured by non-covalent bounds. In this essay some basic properties of network structure and the universal rules that govern them are described. Network or system biology is promising new research approach in biology and medicine.
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Abstract

The image analysis consists in extracting from the information which is available to the observer of the part that is important from the perspective of the investigated process. This process usually accompanies a considerable reduction in the amount of information from the image. In the field of two-phase flows, computer image analysis can be used to determine flow and geometric parameters of flow patterns. This article presents the possibilities of using this method to determine the void fraction, vapor quality, bubble velocity and the geometric dimensions of flow patterns. The use of computer image analysis methods is illustrated by the example of HFE 7100 refrigerant methoxynonafluorobutane condensation in a glass tubular minichannel. The high speed video camera was used for the study, and the films and individual frames received during the study were analyzed.
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Abstract

Material for this paper was collected during the BIOMASS-SIBEX research programme, and consisted of 97 samples taken at 47 stations in Drake Passage and Bransfield Strait (Antarctica). The samples were taken by hauling Nansen nets vertically through the 0-100, 100 - 300 and 300 - 500 m layers at the end of December 1983 and the beginning of January 1984. Four Chaetognatha species were recorded in the study region: Eukrohnia hamata, Sagitta gazellae, Sagitta mari and Sagitta planctonis. The population structures of the dominant species E. hamata and also S. gazellae were analyzed in the context of the region's hydrology. Certain regularities are apparent in the distribution of the developmental stages of E. hamata in water column. Mature specimens of this species inhabit deeper waters than juveniles. The highest proportions of juveniles in the entire population of E. hamata were recorded in slightly warmer waters.
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Abstract

Three Polish Antarctic Geodynamical Expeditions in 1979/80, 1984/85 and 1987/88 undertook seismic investigations in West Antarctica. Seismic measurements, including multichannel seismic reflection and deep seismic soundings, were carried out in the region of the west coast of the Antarctic Peninsula, between Antarctic Sound and Adelaide Island, Bransfield Strait, South Shetland Islands and South Shetland Trench along several lines with a total length of about 5000 km. Selected crustal sections and one and two-dimensional models of the crust for this area are discussed in detail. The thickness of the crust ranges from 30-33 km in the South Shetland Islands to 38—45 km near the coast of the Antarctic Peninsula. The crustal structure beneath the through of Bransfield Strait is highly anomalous; a seismic discontinuity with velocities of 7.0—7.2 km/s was found at a depth of 10 to 15 km, and a second discontinuity with velocities of about 7.6 km/s was found at a depth of 20—25 km. A seismic inhomogeneity along the Deception-Penguin-Bridgeman volcanic line has also been found. A scheme for the geotectonic division and a geodynamical model of the area are discussed. On the base of all experimental seismic data, it will be possible to construct a continuous geotraverse from Elephant Island, across Bransfield Strait, up to Adelaide Island with a total length of about 1100 km. Crustal section and seismic models along the northern segment of the geotraverse from the King George Island to the Palmer Archipelago are discussed in detail here.
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Abstract

The results of the detailed seismoacoustic profilling (CSP, boomar) are presented. The investigation has been carried out in February 1985 and 1988 during two Geodynamical Expeditions organized by the Institute of Geophysics of the Polish Academy of Sciences. The boomar penetration of the caldera floor went down to 150 msec. Four seismoacoustic units of volcanic formations have been determined. The unit A corresponds to pre-caldera series and occurred only in the border part of the flooded caldera. The unit contains mainly pyroclastic rocks (consolidated agglomerates and tuffs) and probably some intercalations of lavas. The units B, C and D fill up the caldera bottom and correspond to post-caldera series. The units are composed of pyroclastic rocks, containing also materials redeposited by lahars, glaciers, landwaters and by wind. The units C and D (the youngest one) were certainly deposited under water. All the units are cut by numerous faults, vents and other types of intrusions. The larger faults, en echelon type, are situated around the bottom and form a ring-fracture. Caldera was formed by succesive stages of collapsing. This process is not finished yet and volcanic activity is still alive (especially in the western part of the flooded caldera).
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Abstract

The paper deals with the structural variability and generative reproduction of Saxifraga oppositifolia populations in eight localities situated in Western Spitsbergen. The localities differed in terms of humidity, soil fertility, microclimate and frequency of disturbances. The population structure, the growth and development rate of individuals in the sea terrace and at the peat-bog prove that a dense plant cover influences positively the development of S. oppositifolia. The size of individuals, their biomass and population density is limited in most of the studied localities. Solifluction is the factor influencing the development of a population to the greatest extent. Of all the researched populations the weakest development was observed in the active structural grounds. Yearly changes in the structure of the populations as well as the yearly growth of the species studied are limited. The longevity, the development rate and size of the seedling recruitment are subject to modifications caused by the solifluction.
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Abstract

The underground mining of coal deposits in the Upper Silesian Coal Basin (GZW) re-sults in an imbalance in the distribution of the stress in the rock mass, both in the immediate and distant surroundings of mining excavations. The occurrence of seismic tremors, among others, is the consequence of this process,. The intensities of seismic phenomena, which occur in several regions of the GZW (Bytomian Basin, Main Saddle, Main Basin, Kazimierzowska Basin, and the Jejkowice Basin) are very diverse, ranging from tremors unrecognizable by humans to strong tremors of the nature of weak earthquakes (Patyńska and Stec 2017). During the period of 15 years, i.e. from 2001 to 2015, the level of seismic activity changed and de-pended on both the intensity of the excavation work and the variability of the lithological and tectonic structures. On the other hand, the seismic activity analysis has shown that in recent years, despite a decrease in total output, seismic activity and rockburst hazard have increased. One of the rea-sons was the increase in mining output. Almost half of the output came from coal seams under the rockburst hazard. This resulted in an increase in the number of great energy tremors with the energy of 107, 108 and 109 J. It has been shown that the amount of energy tremors has a high impact on the level of the rockburst hazard. Between 2001 and 2015, as many as 20 rockburst were caused by seismic tremors above 107 J with 42 total phenomena (Patyńska 2002–2016). The purpose of characterizing the causes of this phenomenon was determined by the parameters characterizing the structure of the rock mass in places where the rockburst was recorded.
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Abstract

During four Polish Geodynamical Expeditions to West Antarctica between 1979 and 1991, seismic measurements were made along 21 deep refraction profiles in the Bransfield Strait and along the coastal area of Antarctic Peninsula using explosion sources. Recordings were made by 16 land stations and 8 ocean bottom seismometers. Good quality recordings were obtained up to about 250 km distance. This allowed a detailed study of the seismic wave field and crustal structure. Three-dimensional tomographic inversion was carried out using first arriv­als from the complete data set including off-line recordings. As a result, we obtained a 3-D model of the P-wave velocity distribution in the study area. In the area adjacent to the Antarctic Peninsula coast, sedimentary cover of 0.2 to 3 km thickness was found, whereas in the shelf area and in the Bransfield Strait sedimentary basins with thickness from 5 to 8 km were observed. In the Bransfield Strait a high velocity body with Vp > 7.5 km/s was found at 12 km depth. The use of the off-line data allowed for determination of the horizontal extent of the body. The thickness of the crust varies from more than 35-40 km in the coastal area south of the Hero Fracture Zone to 30-35 km in the area of Bransfield Strait and South Shetland Islands and about 12 km in the Pacific Ocean NW of South Shetland Islands.
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Abstract

This paper presents preliminary data on the population structure of two Antarctic crustaceans Eudorella splendida and Nototanais antarcticus, commonly occurring in Admiralty Bay (South Shetland Islands). From analysis of the material studied it can be concluded that N. antarcticus is a progynous hermaphrodite with a life cycle lasting at least two years. The life cycle of E. splendida lasts probably 3-4 years. It is a semelparous species, but some females after brooding moult and revert into the intermediate stage.
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Abstract

The study concerns modeling and simulation of the growth of biofilms with heterogeneous structures with a discrete mathematical model based on theory of cellular automata. The article presents two-dimensional density distributions of biofilms for microbial processes: oxidation of ammonium by Nitrosomonas europaea bacteria and glucose utilization by Pseudomonas aeruginosa bacteria. The influence of limiting substrate concentration in the liquid phase on biofilm structure was determined. It has been shown that the value of death rate coefficient of microorganisms has the qualitative and quantitative influence on the density and porosity of the biofilm.
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Abstract

This work attempts to reconstruct the culture that contributed to the philosophical way of thinking. My goal is to extract two important factors: religion carrying individual experience and the importance of certain ideas which are present in that culture. Sources of philosophical thinking can be found in the structure of polis. Only on its basis could the idea of the wise man and citizen as well as religion-oriented individual experience be raised. Greek polis paves the way for a new style of thinking by creating the conditions for its citizens to follow the ideal, regardless of the position they occupy in society. Sustainability, which should be a feature of a good citizen, is also the essence of society. Highly positioned wisdom as moral reflection tinged with religiosity allows thinking according to the laws of logos. Finally, the experience offered by the mystery cults leads to the transformation of their own existence and the emergence of a way of recognition of reality different than before. Undeniably, all the elements related to structure policies with its ideals contribute to the emergence of a new way of thinking in the form of philosophy. One could say that the philosophical objectivity is preceded by the subjectivity and rationality of its roots dating back to irrationality.
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Abstract

In the 19th and in the first half of the 20th century numerous parks were built all over Europe, which, though different in many aspects, still show certain similarities in space structure and composition. The question is, whether late modern public parks, built in the second half on the 20th century follow the classical design and composition „rules”? How did the extremely functionalist design approach of the era after WW2 influence park design? The answer is the result of a detailed analysis on space structure and composition principles of the parks built in these times. In this research I analyzed according to specific criteria the Jubileum Park in Budapest, one of the most prominent work of the late modern period in Hungary. The 12 ha Jubileum Park (built in 1965) is located in the heart of Budapest, on the top of Gellért Hill, next to river Danube. Laying high above the city on an exposed hillside, the park offers a broad view of the whole city. The structure of the park is basically determined by the extreme topography, and one of the great value of the park is the natural looking grading, which determines the space structure and fits to the natural terrain very nicely, and the walkway system, which fits to the contour lines and explores the whole site. Fitting to the windy and exposed hilltop position, in space division the terrain in the most appealing, the plantation is only secondary. From formal point an interesting feature is the dominance of two dimensional elements with characteristic shape, like flowerbeds or ornamental pools and the curves of the walkway system. Though the main function of the park is to underline the fantastic visual potential with providing viewpoints, there are some playgrounds as well. For the visitor of today the specialty of the park celebrating the 50th anniversary this year, is, that – disregarding some minor changes – there were no alterations since it exists. As a first step I analyzed the space structure of the park, putting an extra emphasis on the existence or lack of any axis, on the accentuation of the park entrances, on the space organization inside the park and on the existence/lack of hierarchy. Important aspect of analysis was the connection of the park to connecting urban fabric and green surfaces nearby. The next step was to compare the results with other parks built in former times, but having similar natural setting. The goal of the research is to determine, how much the spatial composition of Jubileum Park is different from the spatial composition of classical parks. The results might help to realize, what kind of spatial composition and space structure is typical of late modern parks. It would be important to preserve these space structural specialties of the Jubileum Park during a more and more urgent renovation.
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Abstract

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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Abstract

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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