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Number of results: 51
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Abstract

Fractal analysis is one of the rapidly evolving branches of mathematics and finds its application in different analyses such as pore space description. It constitutes a new approach to the issue of their natural irregularity and roughness. To be properly applied, it should be encompassed by an error estimation. The article presents and verifies uncertainties along with imperfections connected with image analysis and expands on the possible ways of their correction. One of key aspects of such research is finding both appropriate place and the number of photos to take. A coarse- grained sandstone thin section was photographed and then pictures were combined into one, bigger image. Fractal parameters distributions show their change and suggest that the accurately gathered group of photos include both highly and less porous regions. Their amount should be representative and adequate to the sample. The resolution influence on the fractal dimension and lacunarity values was examined. For SEM limestone images obtained using backscattered electrons, magnification in the range of 120x to 2000x was used. Additionally, a single pore was examined. The acquired results point to the fact that the values of fractal dimension are similar to a wide range of magnifications, while lacunarity changes each time. This is connected with changing homogeneity of the image. The article also undertakes a problem of determining fractal parameters spatial distribution based on binarization. The available methods assume that it is carried out after or before the image division into rectangles to create fractal dimension and lacunarity values for interpolation. An individual binarization, although time consuming, provides better results that resemble reality to a closer degree. It is not possible to define a single, correct methodology of error elimination. A set of hints has been presented that can improve results of further image analysis of pore space.
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Abstract

In order to identify the modal parameters of civil structures it is vital to distinguish the defective data from that of appropriate and accurate data. The defects in data may be due to various reasons like defects in the data collection, malfunctioning of sensors, etc. For this purpose Exploratory Data Analysis (EDA) was engaged toenvisage the distribution of sensor’s data and to detect the malfunctioning with in the sensors. Then outlier analysis was performed to remove those data points which may disrupt the accurate data analysis. Then Data Driven Stochastic Sub-space Identification (DATA-SSI) was engaged to perform the modal parameter identification. In the end to validate the accuracy of the proposed method stabilization diagrams were plotted. Sutong Bridge, one of the largest span cable stayed bridge was used as a case study and the suggested technique was employed. The results obtained after employing the above mentioned techniques are very valuable, accurate and effective.
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Abstract

This paper presents new procedure modeling based on finite element method analysis of wood-framed timber structures. The fasteners linking boards of sheathing with the timber frame both modeled applying shell finite element, with individual material parameters, remain the main objective of this manuscript. Material parameters are obtained from experimental tests and numerical identification. The main objective of the paper is the elaboration of the numerical model with high precision of mapping, and, at the same time, diminishing the number of the unknown simplifying the process of the modeling of timber structures. The new presented method leads to a simplification of analysis of multistory wood-framed multifamily building structures.
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Abstract

The influence that general contractors and subcontractors have on the operation of a company is immense. Keeping this in mind, the authors have decided to develop and algorithm based on the analysis of partnering relations between construction companies that would select the best possible construction company for the purposes of cooperation. This algorithm, developed for a given construction company, is meant to support its decision-making system in the field of the selection of another construction company to cooperate with. The author has made references to earlier research, in which she had used the ELECTRE III method, and in which she bad analysed the possibility of applying the BIPOLAR method in order to solve the problem of the selection of a construction company to develop partnering relations with. The author provided an example of the calculations performed for a selection of construction companies.
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Abstract

Planning a construction project, the investor frequently faces the choice of the option of the planned investment. Assessment of options is difficult due to the complex nature of construction projects. Various methods of multicriteria evaluation are successfully applied in the assessment and analysis of options. For those methods to work, a handful of information must be prepared beforehand. Among others, it is necessary to establish the assessment criteria and determine their weight for specific cases. This stage is implemented in cooperation with experts. The results of evaluations, obtained on the basis of the experts' opinions, must be processed and prepared. The paper will discuss one possible option for assessing the experts' opinion.
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Abstract

This paper presents the study of the impact of vibration induced by the movement of the railway rolling stock on the Forum Gdańsk structure. This object is currently under construction and is located over the railway tracks in the vicinity of the Gdańsk Główny and Gdańsk Śródmieście railway stations. The analysis covers the influence of vibrations on the structure itself and on the people within. The in situ measurements on existing parts of the structure allow us to determine environmental excitations used for validation and verification of the derived FEM model. The numerical calculations made the estimates of the vibration amplitudes propagating throughout the whole structure possible.
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Abstract

W przedmowie do dokumentu Papieskiej Komisji Biblijnej Naród żydowski i jego Święte Pisma w Biblii chrześcijańskiej pierwszy cytat biblijny zwraca uwagę na różnicę między nauczaniem Jezusa, które ma za podstawę Jego osobisty autorytet, a analogiczną działalnością uczonych w P iśmie: „Uczył ich jak ten, który ma władzę, a nie jak uczeni w P iśmie” (Mk 1,22). Kard. Józef Ratzinger, autor przedmowy, stwierdza, że szczególnie Ewangelia Mateusza uwydatnia ten charakter Jego nauczania. Artykuł przedstawia analizę fragmentów tej Ewangelii, które wzmiankują Mojżesza (Mt 8,4; 17,3.4; 19,7.8; 22,24; 23,2). W tym studium szczególną uwagę zwraca się na ich interpretację w bezpośrednim kontekście w tej Ewangelii oraz na ich porównanie z paralelnymi tekstami w pozostałych Ewangeliach synoptycznych. Konkludując, można stwierdzić, że znaczenie słów Mojżesza nie jest pomniejszone, kiedy są one przytaczane w sporach między Jezusem a Jego żydowskimi przeciwnikami. W ten sposób autorytet Jego nauczania, który wyłania się z tych tekstów, zostaje potwierdzony.
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Abstract

The article raised issues related to the design and execution of low-energy objects in Polish conditions. Based on the designed single-family house, adapted to the requirements of the National Fund for Environmental Protection and Water Management ("NF40" standard), the tools to assist investment decisions by investors were shown. An economic analysis and a multi-criteria analysis were performed using AHP method which had provided an answer to the question whether it is worthwhile to bear higher investment costs in order to adjust to the standards of energy-efficient buildings that fulfil a minimal energy consumption's requirements contained in Polish law. In addition, the variant of object that had optimal characteristics due to the different preferences of investors was indicated. This paper includes analysis and observations on the attempts to unify that part of the building sector, which so far is considered to be personalized, and objects in accordance with the corresponding idea are designed as "custom-made".
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Abstract

The research of development capabilities is a fundamental of strategic issues, which has to be taken into consideration by coal mines. This is particularly difficult in the current environment, which is determined by its crisis situation. In such conditions, it is necessary to take difficult decisions, and serious, strategic challenges into account, which allow for the crisis to be overcome, for the renewal and economic effectiveness of the operation of these coal mines, which have potential to grow, and closing the coal mines, which have not potential to grow. Due to the effects of such decisions, which concern not only coal mines but also the Silesian region, it is essential to prepare information to support them and promote rational choices. This is related to the issue of research for development possibilities. The article presents considerations related to the subject of research for development possibilities of coal mines in a crisis situation. Taking the results of literature study into account, the model of research process was developed, and identified the research issues concerning the following: - the identification of external factors which determine the possibility of development of the Polish mines and drawing a schedule of their changes in the future, - the identification of internal factors which determine the possibility of development of the Polish mines, - developing a way for the assessment of the development potential of the coal mines, to show appropriate strategic options and action programmes for these options, - determining possible strategic options and corresponding schedules, appropriate for the specific nature of the mines. The proposition of their solutions, which were obtained in the process of using the specific methods and research tools, allowed the guidelines in terms of research of development capabilities of coal mines to be presented.
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Abstract

Celem artykułu było zbadanie szczegółowego przebiegu tradycyjnego rytuału błogosławieństwa rodziców przed ślubem w sytuacji, kiedy organizują go niewprawni uczestnicy, a znaczenie rytuału nie jest oczywiste w świetle zmian życia rodzinnego. Uznano, że badanie sposobu wykonania rytuału może powiedzieć coś ważnego o jego obecnym znaczeniu. Materiałem empirycznym były filmy weselne. Z wyjściowej bazy 50 filmów wybrano 20 sekwencji błogosławieństw, które poddano transkrypcji i analizie multimodalnej. W wyniku analizy pokazano, że charakterystyczna dla wykonania rytuału była niepewność uczestników, niekompletność i nadmiarowość gestów oraz ogólne zróżnicowanie ich form. Najważniejszym rysem organizacji rytuału w kontekście kształtowania relacji rodzinnych było odgrywanie jednakowości serii gestów rytualnych przez kolejnych wykonawców. Istotne były także nietypowe zmiany kolejności uczestników w sekwencjach rytuału. W dyskusji z koncepcjami, które ujmują kwestię społecznych oczekiwań wobec sposobu kształtowania rodziny w kontekście nierówności społecznych, podjęto próbę interpretacji znaczenia badanego rytuału dla zachowania tradycyjnego obrazu życia rodzinnego i zarazem ochrony statusu jej członków.
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Abstract

Jednym z podstawowych celów realizacji sondaży o charakterze porównawczym jest wnioskowanie o międzykulturowych różnicach opartych na pomiarze pewnych konstruktów latentnych. Porównania takie są uzasadnione, jeśli tylko owe konstrukty mierzą w każdym kraju to samo oraz w taki sam sposób. Celem tego artykułu jest weryfikacja hipotezy o ekwiwalentności pomiaru skali zaufania politycznego w dwudziestu krajach uczestniczących w siódmej rundzie Europejskiego Sondażu Społecznego. Analiza stopnia dopasowania modeli pomiarowych opartych na równaniach strukturalnych pozwoliła przyjąć hipotezę o konfiguralnej oraz metrycznej ekwiwalentności pomiaru skali zaufania politycznego. Jednocześnie odrzucono hipotezę o pełnej inwariancji skalarnej tego konstruktu, przy czym najbardziej problematyczny okazał się pomiar wskaźnika zaufania do systemu prawnego. Na zakończenie ukazano możliwości wnioskowania o międzykrajowych różnicach w poziomie zaufania politycznego, pomimo odrzucenia hipotezy o pełnej inwariancji pomiarowej tego konstruktu.
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Abstract

Celem artykułu jest pokazanie zmian użycia metafor „czerwony autobus” i „autobus” w polskiej kulturze popularnej na przestrzeni ostatnich kilkudziesięciu lat. Znaczenie badania leży w powiązaniu ich ze sposobem przedstawiania społeczeństwa polskiego oraz zbiorowym doświadczaniem i wytwarzaniem emocji. Autorzy zastosowali koncepcje teoretyczne i narzędzia analizy dyskursu. Jako materiał badawczy wykorzystali zbiór 20 polskich utworów muzycznych z lat 1952–2014, w których metafora „autobus” pełniła ważną rolę, wykorzystując ją jako domenę źródłową dla obrazowania stanu zbiorowości. W rezultacie syntetycznego zestawienia treści metafory i zbadania jej umieszczenia w tekście oraz bardziej szczegółowej analizy kontekstowej wybranych utworów autorzy wykazali tendencję do ukazywania społeczeństwa jako wspólnoty ludzi obcych, ale jednocześnie bliskich ze względu na podzielanie pozycji relatywnego wykluczenia, braku zbiorowego celu i indywidualnego wpływu, a także doświadczanie różnych emocji negatywnych.
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Abstract

The iron ore mine owned by the state concern of Luossavaara – Kiirunavaara AB-LKAB state concern has several mining skip shaft hoists for drawing iron ore. Despite using modern systems to secure the travel of these hoists in line with the Swedish regulations, units intended for the emergency breaking of vessels must be used in the so-called free travel paths in the tower and in the shaft sump. The paper discusses the main requirements that, in accordance with the Swedish regulations as regards the operational use of mining shaft hoists, must be met by devices of this type and a solution was proposed for a structure design of the braking unit for the mining shaft hoist installed in the B-1 shaft in the Kiruna mine. The frictional braking system in the form of moving bumping beams was decided to be used in the said hoist, developed in the Cable Transport Department in the University of Science and Technology in Krakow. The action of moving bumping beams consists in these beams, placed at the beginning of free travel paths, not only braking the rushing hoist vessels but also (with the integrated units for vessel capture) performing the function of grips. They secure the vessels against falling down into the shaft after the finished braking process. The advantage of such a solution is that the structural elements: the guiding shank of the tower, the head of the vessel and the bumping beams, transfer many times lower values of dynamic forces at the time of the strike of the vessel against the moving bumping beams when compared with dynamic forces arising at the time of the hit of the vessel against the fixed bumping beams. In the process of designing moving bumping beams, braking simulation is an important stage conducted with a computer program developed in KTL AGH. This program enables the modelling of load-bearing and balance ropes as flexible elements with elastic and suppressing properties. The results of these simulations, especially in the scope of the achieved braking deceleration of the vessels, the values of braking distances and forces in the load-bearing ropes are crucial in confirming the correctness of the assumed concept of the emergency braking system. The braking units in the form of moving bumping beams have been executed by the Polish company Coal-Bud Sp. z o.o. and are now being integrated in the tower and in the shaft sump of the B-1 shaft of the Kiruna mine in Sweden.
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Abstract

The issue of the morphemic analysis of medical terminology is a crucial factor in terms of translation strategies and compilation of a terminological dictionary. The research was conducted in the context of author’s current lexicographical work called as English-Ukrainian-Russian defining dictionary of dental terms. To provide the user of the dictionary with reliable techniques to construct the meaning of terms, morphemes relative frequency in the area of dentistry have been determined.
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Abstract

CCS (Carbon Capture and Storage) technology is one of the methods that limit the release of carbon dioxide into the atmosphere. However, the high cost of capturing CO2 in this technology is a major obstacle to the implementation of this solution by power plants. The reduction of costs is expected primarily on the side of the capture and separation of CO2 from flue/ industrial gas. The article presents the financial performance of the most popular amine technology (MEA) against mesoporous material about MCM-41 structure obtained from fly ash, impregnated with polyethyleneimine (PEI), for CCS installations. The study was conducted for an investment comprising three key components that provide a full value chain in CCS validation (capture, transport and storage). The mineralogical studies and determination of the physicochemical properties of mesoporous material produced from waste materials such as fly ash allowed us to identify the best class sorbents of MCM-41, which can be used in CO2 capture technologies. Developing an innovative relationship not only allows 100% of CO2 to be removed but also reduces operating costs (OPEX), primarily including energy by 40% and multiple material costs relative to amine mixtures such as MEA.
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Abstract

The standard PN-EN_1993-1-5:_2008 (Eurocode 3) compared with the standard (PN-B-03200:_1990) used previously in Poland, introduces extended rules referring to the computations of the bearing capacity of the plated structural elements including the shear lag effect. The stress distribution in the width flanges is variable. Therefore in the case of the beam with the shear lag effect cannot be calculated by the classic beam theory. In this article a comparison of the results of the calculations of forces distribution, stresses and displacement according to the rule presented in PN-EN_1993 and results of the numerical computations for_3D model (using finite element method) is presented. The elastic shear lag effects, the elastic shear lag effects including effects of the plate buckling and the elastic-plastic shear lag effects including the local instabilities were analysed. The calculations were performed for beams with a small and a large span and an influence of stiffeners was analysed.
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Abstract

For the construction company, tendering is the most popular way of acquiring contracts. The decision to participate in the tender needs to be made carefully, as it affects the condition of the company and is an important aspect in its quest for success. The bid/no bid decision making is a complex process involving a number of factors. The research carried out so far has mainly concerned the identification of the various kinds of influences on contractors’ bidding decisions. The researchers, on the basis of contractors’ opinions, created rank lists in an attempt to categorize the factors. In this paper the author employs factor analysis which belongs to basic methods of multi-dimensional data analysis. The paper’s aim is first to depict an output set of observed variables, that is bid/no bid factors, in terms of a smaller set of latent variables which cannot be directly observed and then to interpret the dependencies between them.
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Abstract

During the planning and controlling of the construction process, most attention is focu sed on risk analysis, especially in the context of final costs and deadlines of the investment. In this analysis, the primary and most significant concern is the proper identification and quantification of events, which on a certain level of probability may affect the development process. This paper presents the result of a risk analysis for a particular building object, made after completion of the investment and accepting it for use. Knowledge of the planned values and the actual investment process allowed for the identification of the events and their effects that in this case have significantly disrupted the investment process. The limited total cost of the investment project in question had a considerable impact on the progress of the project execution. Despite three transitions of administrative procedures, the opening date of the shopping centre was delayed by only three weeks.
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Abstract

The research paper presents the results of the dynamic analysis of an existing bar dome subjected to wind loads. The calculation model of the structure was constructed using the finite element method. The dome was subjected to the standard wind pressure, assuming that it is operates in a harmonic manner. The numerical analyses were performed with the application of Autodesk Robot and MES3D. The analysis focused on the impact of selected factors such as the frequency of forcing, wind gustiness coefficient and structural damping on the behaviour of structures.
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Abstract

This article deals with the problem of determining the resistance of end-plate connections. A nonlinear FEM model of the joint was constructed in order to predict its carrying capacity. A standard code procedure was done as well. The analyses have been done to assess atypical end-plate joints designed and constructed as a part of roof structures.
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Abstract

Modern regulations concerning railway bridges are based on the approach of structural dynamics, which is described in PN-EN standards. This paper presents the results of theoretical dynamic analysis of the HSLM-A train set loading on the structure of a pre-stressed concrete arch bridge - the first railway bridge of its type which was built in Poland (completed in 1959). The recommendations of PN-EN have been followed and modal analysis was carried out to define the sensitivity of the structure to chosen eigenforms. Additionally the paper presents a course of calculations and the conclusions obtained from the analysis of displacements, accelerations, and bending moments induced in the structure through a simulated passage of a high-speed train in the context of the requirements of PN-EN Standards. The conclusions from the current calculations can be used for dynamic analysis of bridges of similar structural solutions.
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Abstract

Transportation networks respond differently to applied policies. The Tehran Metropolitan Area has one of the most complex networks with complex users, which has experienced many of these policies change within the past decades. In this study, some of these policies and their effect on air pollution is investigated. The goal is to pinpoint the variables which have the most effect on various transportation models and investigate how new policies should be focused. In order to do so, long-term variations of air pollution monitoring stations were analyzed. Results show that the most significant parameter that may affect air pollution is users' behavior due to the lack of a public transportation network and its level of comfort. The results of this study will be useful in developing new policies and evaluating their long-term consequences in appropriate models.
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Abstract

The preliminary stage of asphalt mixture production involves the drying and dedusting of coarse aggregates. The most common types of coarse aggregates used are limestone and basalt. In the process of drying and dedusting the dryer filter accumulates large quantities of waste in the form of mineral powder. This paper introduces an investigation into limestone powder waste as a potential microfiller of polymer composites. Physical characteristics such as the granulation the of powder collected from the filter - in terms of the season of its collection and the type of input materials used - were analysed. A scanning electron microscope (SEM) was used for the investigation described within this paper. The obtained results were compared against those of other materials which can be used as polymer composites microfillers.
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